CN116761767A

CN116761767A - Defect detection in moving fibrous structures

Info

Publication number: CN116761767A
Application number: CN202180070686.XA
Authority: CN
Inventors: P·科菲; M·伊万斯基
Original assignee: Kuraray America Inc
Current assignee: Kuraray America Inc
Priority date: 2020-10-21
Filing date: 2021-10-21
Publication date: 2023-09-15
Also published as: KR20230091888A; WO2022087193A1; EP4232802A1; JP2023546917A; CA3189645A1

Abstract

Disclosed herein are methods and apparatus (100) for detecting defects in a fibrous structure (110) using at least one defect detector comprising a projector (115) and a light receiver (130) capable of measuring a cross-sectional diameter of the fibrous structure upon linear movement. The cross-sectional diameter is calculated based on a reduction in the amount of light (135) detected by the light receiver relative to the total amount of light (140) transmitted by the projector. Also disclosed herein are fibrous structures that have been subjected to the defect detection method.

Description

Defect detection in moving fibrous structures

Technical Field

The present application relates generally to materials technology, and more particularly to the preparation, processing and inspection of fiber-containing structures such as threads, strands and skein structures. More specifically, methods and apparatus for detecting and characterizing defects in a fibrous structure in linear motion in real time are disclosed.

Background

When producing or processing fiber-containing structures, such as filaments (e.g., multifilament threads), braids (e.g., braided yarns, braided core-sheath structures, etc.), and skeins (e.g., skeins), defects may occur due to, for example, the presence of broken filaments and impurities.

For example, broken filaments may occur due to stretching, bending or twisting of the fibrous structure. When broken filaments are present on the surface of the fibrous structure undergoing in-line processing, such broken filaments weaken the fibrous structure and also separate and then reattach at different locations along the fibrous structure, resulting in additional defects. The broken fibers, whether attached to or detached from the precursor filaments, change shape and increase in size during subsequent in-line processing.

Although the terminology of defects associated with fibrous structures may vary greatly in the relevant art, defects caused by broken filaments and impurities are generally classified into two categories. The first category involves broken filaments (single filaments or multiple sets of filaments) extending outwardly from the surface of the fibrous structure as a branched structure, commonly referred to as "fluff" or "peel" defects. The second category involves breaking (separating) fibers or other impurities that adhere to the surface of the fibrous structure and tend to grow into hillock-like structures during in-line processing-commonly referred to as "globules" or "bamboo joint" defects.

Because the above-described defects can adversely affect the strength and utility of the fibrous structure, commercially available products are typically inspected and rated based on the number or concentration of defects. Although the process of grading fibrous structures is typically performed by a human inspector using a magnifying device (e.g., a microscope), manual inspection can be a very tedious process that is not well suited for mass production. Furthermore, due to limitations associated with manual inspection, manual inspection is rarely used to perform real-time corrective intervention to reduce or eliminate defect formation during high-speed production or processing of fibrous structures.

Disclosure of Invention

The present inventors have recognized that there is a need to find methods and apparatus for reliably detecting defects in fibrous structures while in linear motion during production or processing. There is also a need for such a method and apparatus to be able to distinguish and characterize defects and modify or terminate the production or processing of fibrous structures so as to reduce the occurrence of defects.

The following disclosure describes methods and apparatus for detecting defects in a fiber-containing structure in real-time in linear motion, and fiber-containing structures obtained using these methods and apparatus.

Embodiments of the present disclosure described herein to enable one of ordinary skill in the art to make and use them include the following:

(1) One aspect relates to a method for detecting defects in a fibrous structure by: linearly passing the fiber-containing structure through at least one defect detector, measuring at least one cross-sectional diameter of the fiber-containing structure with the defect detector to obtain at least one diameter signal of the fiber-containing structure for a diameter versus length, optionally, signal processing the diameter signal to obtain at least one signal processed diameter signal; and comparing the diameter signal, the signal processed diameter signal, or a combination thereof to at least one reference signal to produce at least one surface defect signal output for the length of the fibrous structure, wherein (a) the defect detector measures the cross-sectional diameter of the fibrous structure by: transmitting light onto the fiber-containing structure with a projector, detecting a profile image of the fiber-containing structure with a light receiver, and calculating a cross-sectional diameter based on a decrease in an amount of light detected by the light receiver relative to a total amount of light transmitted by the projector; and (b) at least one defect detector is in series with an extrusion apparatus configured to form the fibrous structure, a braiding machine configured to form the fibrous structure, a tensioning assembly configured to apply tension to the fibrous structure, a finish applicator configured to apply a coating to the fibrous structure, a godet assembly configured to stretch the fibrous structure, a winding assembly configured to wind the fibrous structure onto a spool, or a combination thereof;

(2) Another aspect relates to a defect-detecting fibrous structure obtained by performing the above-described method (1); and

(3) Another aspect relates to an apparatus for detecting defects in a fibrous structure, the apparatus comprising: (A) An extrusion apparatus configured to form a fibrous structure, a braiding machine configured to form a fibrous structure, a tensioning assembly configured to apply tension to the fibrous structure, a finish applicator configured to apply a coating to the fibrous structure, a godet assembly configured to stretch the fibrous structure, a winding assembly configured to wind the fibrous structure onto a spool, or a combination thereof; (B) A defect detector configured to measure at least one cross-sectional diameter of the fibrous structure by: transmitting light onto the fiber-containing structure with a projector, detecting a profile image of the fiber-containing structure with a light receiver, and calculating a cross-sectional diameter based on a decrease in an amount of light detected by the light receiver relative to a total amount of light transmitted by the projector; and (C) a processor configured to compare the at least one diameter signal, optionally the at least one signal processed diameter signal, or a combination thereof, obtained from the defect detector to at least one reference signal to obtain at least one surface defect signal of the surface defect output versus the length of the fibrous structure, wherein the defect detector measures the at least one cross-sectional diameter as the fibrous structure passes linearly through the defect detector.

Additional objects, advantages, and other features of the disclosure will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the disclosure. The present disclosure includes other embodiments than the ones specifically described below, and the details herein can be modified in various respects without departing from the disclosure. In this regard, the description herein is to be construed as illustrative in nature and not as restrictive.

Drawings

Embodiments of the present disclosure are explained in the following description in view of the drawings, in which:

FIG. 1A shows a non-twisted, non-woven filament formed from a plurality of filaments or filament-containing strands;

FIG. 1B illustrates a braided fibrous structure formed from a plurality of filaments or filament-containing strands braided together;

FIG. 1C illustrates a core-sheath fibrous structure comprising a core of filaments or filament-containing strands surrounded by a sheath formed from a plurality of filaments or filament-containing strands woven together;

FIG. 1D illustrates a skein fiber-containing structure comprising a core of filaments or filament-containing strands surrounded by a skein cover formed of a plurality of filaments or filament-containing strands skein together in the same direction;

FIG. 2A shows a fibrous structure having defects in the form of "fuzz" or "lift-off" caused by broken filaments;

FIG. 2B shows a fibrous structure having defects in the form of small "globules" or "bamboo joints" caused by impurities adhering to the surface of the fibrous structure;

FIG. 2C illustrates a fibrous structure having defects in the form of elongated "globules" or "bamboo joints" caused by the accumulation of impurities attached to the surface of the fibrous structure;

FIG. 3 illustrates a defect detector configured to detect and measure a cross-sectional diameter of a fiber-containing structure;

FIG. 4A shows a light projecting slit of a defect detector through which a band-shaped parallel light passes;

fig. 4B shows a light receiving slit of the defect detector through which a part of the blocked parallel light passes;

FIG. 5A shows a light receiving slit of a defect detector with parallel light being partially blocked by a defect-free portion of a fiber-containing structure that passes linearly through the defect detector;

FIG. 5B shows a light receiving slit of a defect detector with parallel light blocked by a portion of the defect containing fiber structure that is linearly passed through the defect detector;

FIG. 6A shows a moving fibrous structure having delamination defects caused by broken filaments and shows the locations of cross-sectional measurements of fibrous structures occurring at regular intervals;

FIG. 6B shows a moving fibrous structure with small bamboo defects caused by adhering impurities and shows the locations of cross-sectional measurements of fibrous structures occurring at regular intervals;

FIG. 6C illustrates a moving fibrous structure having elongated bamboo defects caused by accumulated impurities and shows the locations of cross-sectional measurements of fibrous structures occurring at regular intervals;

FIG. 7 illustrates an apparatus for producing or processing a fibrous structure;

FIG. 8 illustrates an apparatus for braiding and inspecting a fibrous structure; and

fig. 9 shows a defect detector array comprising two dual-axis defect detectors arranged in series with respect to a fibrous structure that moves linearly through the defect detector array.

Detailed Description

Embodiments of the present disclosure include various methods for detecting defects in a moving fibrous structure, apparatus for performing the defect detection method, and a defect-detected fibrous structure obtained by performing the defect detection method described herein. Certain non-limiting applications of the defect detection methods of the present disclosure are also described herein.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the relevant art. In case of conflict, the present specification, including definitions, will control.

All percentages, parts, ratios, etc., are by weight unless otherwise specified.

When an amount, concentration, or other value or parameter is given as either a range or a list of upper and lower limits, this is to be understood as specifically disclosing all ranges formed from any pair of any upper and lower limits, regardless of whether ranges are separately disclosed. Unless otherwise indicated, the numerical ranges recited herein are intended to include the endpoints thereof, and all integers and fractions within the range. When defining ranges, it is not intended that the scope of the disclosure be limited to the specific values recited.

The use of "a" or "an" to describe various elements and components herein is merely for convenience and to give a general sense of the disclosure. The description should be read to include one or at least one and the singular also includes the plural unless it is clear that it is meant otherwise.

Unless explicitly stated to the contrary, "or" and/or "refer to inclusion, rather than exclusivity. For example, condition a or B, or a and/or B satisfies any one of the following conditions: a is true (or present) and B is false (or absent), a is false (or absent) and B is true (or present), both a and B are true (or present).

The terms "about" and "approximately" as used herein mean about the same as a reference amount or value and should be understood to include + -5% of the specified amount or value.

The term "substantially" as used herein, unless otherwise defined, refers to all, or nearly all, or the vast majority, as understood by one of ordinary skill in the art in the context of use. It is intended to take into account some reasonable differences from 100% that typically occur in the case of an industrial or commercial scale.

In this specification, unless otherwise defined and described, the technical terms and methods used to determine relevant measurements are in accordance with the descriptions of ASTM D855/D885M-10A (2014), standard Test Methods for Tire Cords, tire Cord Fabrics, and Industrial Filament Yarns Made From Man-wide Organic-base Fibers published 10 month 2014.

For convenience, many of the elements of the various embodiments disclosed herein are discussed separately. Although lists of options may be provided and values may be within ranges, the present disclosure should not be considered limited to the list and ranges described separately. Each possible combination in the present disclosure is to be considered as being explicitly disclosed for all purposes unless the context clearly indicates otherwise.

The materials, methods, and examples herein are illustrative only and, unless otherwise indicated, are not intended to be limiting. Methods and materials similar or equivalent to those described herein can also be used in the practice of the present invention.

Method for detecting defects in moving fibrous structures

Disclosed herein are methods for detecting defects in a fibrous structure in linear motion. The term "fiber-containing structure" includes any cord-like structure formed from fibers and/or filaments, such as filaments, braids, skeins, and core-sheath structures.

Fig. 1A to 1D show examples of fibrous structures that can be used in the method of the invention.

Fig. 1A shows an example of a filament cord 5 comprising a plurality of filaments (or filament-containing strands) 10, the filaments 10 being arranged in a non-twisted, non-woven bundle. Fig. 1B shows an example of a braided cord 15 comprising a plurality of filaments (or filament-containing strands) 20, the filaments 20 being arranged in a braided bundle without a central core. Fig. 1C shows an example of a braided cord 25 having a core-sheath structure that includes a braided sheath 30 formed of a plurality of braided filaments (or braided filament-containing strands) 32 surrounding a core 35 formed of filaments (or filament-containing strands). Fig. 1D shows a skein fiber-containing structure 40 having a core-sheath structure comprising a skein 45 formed of a plurality of braided filaments (or braided filament-containing strands) 50 surrounding a core 55 formed of filaments (or filament-containing strands).

As mentioned above, certain drawbacks may occur when producing or processing fibrous structures, for example due to damaged filaments or impurities that may adhere to the fibrous structures.

Fig. 2A shows a generic fibrous structure 60 having defects 65 in the form of "fuzz" or "lift-off" caused by broken filaments. For example, broken filaments may occur due to tensioning, bending or twisting of the fibrous structure. Typically, during processing, the broken filaments extend outwardly at an acute angle 70 relative to the direction of travel 75 of the linear motion of the fibrous structure 60. However, in some cases, the broken filaments may extend outwardly at an obtuse angle relative to the direction of travel of the fibrous structure. In some cases, the broken filaments may include two branched structures including a leading edge branch 67 extending outwardly at an obtuse angle relative to the direction of travel (as shown in fig. 5A and 5B) and a trailing edge branch 65 extending outwardly at an acute angle (as shown in fig. 2A).

Fig. 2B shows a typical fibrous structure 80 having defects 85 in the form of "globules" or "bamboo joints" caused by impurities adhering to the surface of the fibrous structure 80. The example of fig. 2B illustrates a small (recently introduced) impurity, wherein the attachment points 87 of the "beads" or "bamboo joints" occupy a relatively small area compared to the overall size of the "beads" or "bamboo joints".

Fig. 2C shows a typical fibrous structure 90 having defects 95 in the form of elongated or enlarged "globules" or "bamboo joints" caused by the accumulation or formation of impurities adhering to the surface of the fibrous structure 90. The example of fig. 2C shows an elongated or enlarged impurity wherein the attachment points 97 of the "beads" or "bamboo joints" occupy a relatively large area compared to the overall size of the "beads" or "bamboo joints".

The defect detection method of the present disclosure employs a defect detector configured to measure at least one cross-sectional diameter of a moving fibrous structure.

Such a method may comprise the steps of: (1) Passing the fibrous structure linearly through at least one defect detector; (2) Measuring at least one cross-sectional diameter of the fibrous structure with a defect detector to obtain at least one diameter signal of diameter versus length of the fibrous structure; (3) Optionally, signal processing the diameter signal to obtain at least one signal processed diameter signal; and (4) comparing the diameter signal, the signal processed diameter signal, or a combination thereof with at least one reference signal to produce a surface defect output versus at least one surface defect signal for the length of the fiber-containing structure.

In some embodiments, the defect detector measures the cross-sectional diameter of the fibrous structure by: the light is transmitted to the fiber containing structure with a projector, a profile image of the fiber containing structure is detected with a light receiver, and a cross-sectional diameter is calculated based on a decrease in an amount of light detected by the light receiver relative to a total amount of light transmitted by the projector.

Fig. 3 shows an example of a defect detector 100, the defect detector 100 being configured to measure a cross-sectional diameter of a fibrous structure in linear motion by detecting a profile image 105 of the fibrous structure 110. In this embodiment, the defect detector 100 includes a projector 115 including a light source 120 and a lens 125, and a light receiver 130 for detecting the profile image 105. The cross-sectional diameter of the fiber-containing structure 110 is calculated based on the reduction in the amount of light 135 detected by the light receiver relative to the total amount of light 140 transmitted by the projector. The optical receiver 130 generates a diameter signal 145 that is sent to the processor 150, the processor 150 being configured to (i) optionally perform signal processing of the diameter signal 145 to obtain a signal processed diameter signal, and (ii) compare the diameter signal 145, the optional signal processed diameter signal, or a combination thereof to at least one reference signal 155 to generate at least one surface defect signal 160 of the surface defect output versus the length of the fibrous structure 110. In the embodiment of fig. 3, the light receiver 130 includes an active pixel sensor 165.

Various projectors and optical detectors known in the relevant art may be used in the defect detector of the present disclosure. For example, the projector may include a laser diode and/or a light emitting diode, and the light receiver may include an active pixel sensor. Active pixel sensors used in the optical detectors of the present disclosure may include photodiode image sensors, charge Coupled Device (CCD) image sensors, complementary Metal Oxide Semiconductor (CMOS) image sensors, or combinations thereof.

The methods of the present disclosure may employ commercially available equipment capable of detecting contour images of fibrous structures in linear motion. For example, the transmissive sizing device described in US2010/0271638 by Torii et al may be used as a defect detector in the methods and apparatus of the present disclosure.

The methods of the present disclosure may also use different types of detectors known in the relevant art that are capable of imaging the surface of the fibrous structure in linear motion. For example, the detection method may further comprise the step of imaging the surface of the fibrous structure with at least one imaging detector capable of imaging the surface by illuminating the fibrous structure with imaging light and receiving the reflected image of the surface with an imaging receiver. Alternatively, the detection methods of the present disclosure may not include imaging the surface of the fibrous structure with an imaging detector that receives the reflected image of the surface.

Fig. 4A and 4B show how the defect detector of the present invention measures the cross-sectional diameter of a fiber-containing structure.

As described and illustrated above, the defect detector 100 measures the cross-sectional diameter of the fibrous structure 110 by transmitting light 140 to the fibrous structure 110 with the projector 115 and then detecting the profile image 105 of the fibrous structure 110 with the light receiver 130, see fig. 3.

Fig. 4A shows an embodiment in which projector 115 includes a light projecting slit 170 through which light emitted from light source 120 passes and is shaped into a ribbon-shaped parallel beam 175. Fig. 4B shows an embodiment in which the respective light receiver 130 comprises a light receiving slit 185 through which the partially blocked parallel light beam 135 passes before being detected by, for example, the active pixel sensor 165.

In the illustrations of FIGS. 4A and 4B, the presence of a defect-free portion 190 of the fiber-containing structure 110 (linearly passing through the defect detector 100 at a linear velocity v) results in a portion of the parallel beam 175 being blocked-such that the amount A of the partially blocked parallel beam 135 detected by the optical receiver 130 ^D Quantity a less than parallel light beam 175 transmitted by projector 115 ^T . The blocked portion of the parallel light beam 135 corresponds to the profile image 105 of the fibrous structure 110. In this way, the cross-sectional diameter D of the fiber-containing structure 110 may be based on the amount A of transmitted parallel light beams 175 ^T And the amount A of the partially blocked parallel light beam 135 ^D The difference between them is calculated-namely D-A ^T –A ^D )。

Fig. 5A and 5B show how the profile image 105 of the fibrous structure changes when a defect is detected by the defect detector 100.

Fig. 5A shows the light receiving slit 185 of the defect detector 100 at time t1, when the parallel light beam 175 is partially blocked by the defect-free portion 190 of the fibrous structure 110 (linearly traversing the defect detector 100 at a linear velocity v). As described above, the blocked portion of the parallel light beam 135 corresponds to the profile image 105' of the fibrous structure 110. In this way, the amount A of transmitted parallel light beam 175 can be based on ^T And the amount A of the partially blocked parallel light beam 135 ^D ₁ The difference between (i.e. D ₁ ～(A ^T –A ^D ₁ ) To calculate the cross-sectional diameter D of the defect-free portion 190 at time t 1) ₁ 。

Fig. 5B shows the light receiving slit 185 of the defect detector 100 at time t2, when the parallel light beam 175 is partially blocked by the defect-containing portion 195 of the fibrous structure 110 (linearly traversing the defect detector 100 at a linear velocity v). At time t2, the blocked portion of the parallel light beam 200 corresponds to the profile image 105 "of the fibrous structure 110. In this way, the amount A of transmitted parallel light beam 175 can be based on ^T And the amount A of the partially blocked parallel light beam 195 ^D ₂ The difference between (i.e. D ₂ ～(A ^T –A ^D ₂ ) To calculate the cross-sectional diameter D of the defect-containing portion 195 at time t2 ₂ 。

Because the defect-containing portion 195 shown in FIG. 5B includes defects 67 in the form of "fuzz" or "lift-off" caused by broken filaments, more of the parallel beam 175 is blocked at time t2 than at time t 1. Thus, in this illustration, the cross-sectional diameter D of the defect-containing portion 195 calculated in FIG. 5B ₂ Greater than the calculated cross-sectional diameter D of defect-free portion 190 in FIG. 5A ₁ . In other embodiments, the cross-sectional diameter D of the defect-containing portion ₂ May be smaller than the cross-sectional diameter D of the defect-free portion of the fibrous structure 110 ₁ . For example, when a portion of the broken filaments breaks from the fibrous structure, the resulting cross-sectional diameter of the defect-containing portion may be smaller than the corresponding cross-sectional diameter of the defect-free portion of the fibrous structure.

As explained in more detail below, measuring at least one cross-sectional diameter of the fibrous structure with at least one defect detector is performed at regular (time/distance) intervals as the fibrous structure is passed linearly through the defect detector at a linear velocity v. In so doing, the measurement of the at least one cross-sectional diameter may be performed at a sampling rate of about 1 sample per second to at least 5000 samples per second. In some embodiments, the sampling rate of at least one defect detector is adjusted such that measurements are taken at constant intervals along the length of the fibrous structure. The constant interval at which the measurement occurs may be in the range of about 10nm to about 1 cm.

After the step of measuring at least one cross-sectional diameter of the fiber-containing structure with the at least one defect detector and optionally the step of signal processing the diameter signal to obtain at least one signal processed diameter signal, the method of the present disclosure may comprise the steps of: the diameter signal and/or the signal processed diameter signal is compared with at least one reference signal to generate at least one surface defect signal of the surface defect output versus the length of the fibrous structure. As described below, the at least one surface defect signal may be related to the amplitude, slope, and/or curvature of the diameter signal.

The surface defect signal may comprise an amplitude surface defect count signal of an amplitude surface defect count versus a length of the fibrous structure. An amplitude surface defect count signal is generated by comparing the diameter signal to a reference signal for the length of the fibrous structure by the maximum cross-sectional diameter. The amplitude surface defect count is zero when the amplitude of the diameter signal is less than or equal to the maximum cross-sectional diameter at a particular point along the length of the fiber-containing structure. When the amplitude of the diameter signal is greater than the maximum cross-sectional diameter at a particular point along the length of the fiber-containing structure, the amplitude surface defect count is greater than zero, such that the amplitude surface defect count greater than zero may be a positive integer corresponding to the amplitude of the diameter signal being greater than a percentage of the maximum cross-sectional diameter.

The surface defect signal may comprise a slope surface defect count signal of a slope surface defect count versus a length of the fibrous structure. A slope surface defect count signal is generated by comparing a signal-processed diameter signal obtained by signal processing the diameter signal to obtain a first derivative of the diameter signal with a reference signal containing the maximum first derivative of the fiber structure length. The slope surface defect count is zero when the absolute value of the first derivative of the diameter signal is less than or equal to the maximum first derivative of the diameter signal at a particular point along the length of the fibrous structure. When the absolute value of the first derivative of the diameter signal is greater than the maximum first derivative of the diameter signal at a particular point along the length of the fibrous structure, the slope surface defect count is greater than zero such that the slope surface defect count greater than zero may be a positive integer corresponding to the absolute value of the first derivative of the diameter signal being greater than a percentage of the maximum first derivative of the diameter signal.

The surface defect signal may comprise a curvature surface defect count versus fiber-containing structure length curvature surface defect count signal. A curvature surface defect count signal is generated by comparing the signal-processed diameter signal obtained by signal processing the diameter signal to obtain a second derivative of the diameter signal with a reference signal containing the maximum second derivative of the fiber structure length. The curvature surface defect count is zero when the absolute value of the second derivative of the diameter signal is less than or equal to the maximum second derivative of the diameter signal at a particular point along the length of the fibrous structure. When the absolute value of the second derivative of the diameter signal is greater than the maximum second derivative of the diameter signal at a particular point along the length of the fiber-containing structure, the curvature surface defect count is greater than zero, such that the curvature surface defect count greater than zero may be a positive integer corresponding to the absolute value of the second derivative of the diameter signal being greater than a percentage of the maximum second derivative of the diameter signal.

The detection methods of the present disclosure may further include the step of distinguishing and/or classifying defects contained in the fibrous structure based at least in part on the amplitude, slope, and/or curvature of the diameter signal. The detection methods of the present disclosure may further include the step of generating a surface defect grade of the fibrous structure based on the amplitude, slope, and/or curvature of the diameter signal.

Fig. 6A to 6C show how the variation of the cross-sectional diameter of the defect-containing portion of the fibrous structure can be used to count, differentiate and classify different defects.

Fig. 6A shows the locations of cross-sectional measurements taken on the fibrous structure 110 at regular intervals from time t1 to t 8. The fibrous structure 110 (passing linearly through the defect detector 100 at a linear velocity v) comprises a defect-containing portion 195 having defects 65 in the form of "fuzz" or "lift-off" caused by broken filaments. In this illustration, the cross-sectional diameters calculated at times t2, t3, t4, and t5 indicate the presence of "fuzz" or "lift-off defects 65 caused by broken filaments.

Focusing on the magnitude of the cross-sectional diameter of the fibrous structure 110 within the defect-containing portion 195, FIG. 6A shows where (i) the magnitude increases slightly at time t3 relative to time t2 (a magnitude surface defect count of slightly greater than zero occurs at time t 3), (ii) the magnitude increases more significantly at time t4 relative to time t2 (a magnitude surface defect count of significantly greater than zero occurs at time t 4), and then (iii) the magnitude decreases abruptly at time t5 relative to time t4 (a magnitude surface defect count of zero occurs at time t 5). This pattern of a slight increase in the amplitude surface defect count at time t3, combined with a sudden decrease back to zero in the amplitude surface defect count at time t5, indicates the presence of "fuzz" or "lift-off" defects caused by broken filaments having only a single branch (i.e., a trailing branch extending outwardly at an acute angle with respect to the direction of travel-see fig. 2A).

Focusing on the slope of the cross-sectional diameter of the fibrous structure 110 within the defect-containing portion 195, FIG. 6A shows where (i) the slope increases at time t3 relative to time t2 (a slope surface defect count that is slightly greater than zero occurs at time t 3), (ii) the slope remains constant or increases slightly at time t4 relative to time t3 (a slope surface defect count that is greater than zero occurs at time t 4), and then (iii) the slope suddenly decreases at time t5 relative to time t4 (a slope surface defect count that is zero occurs at time t 5). This pattern of increasing the slope surface defect count at time t3, combined with the abrupt decrease back to zero in the slope surface defect count at time t5, indicates the presence of "fuzz" or "lift-off" defects caused by broken filaments having only a single branch (i.e., trailing branch extending outwardly at an acute angle relative to the direction of travel-see fig. 2A).

Fig. 6B shows the locations of cross-sectional measurements taken on the fibrous structure 110 at regular intervals from time t1 to t 8. The fibrous structure 110 (passing linearly through the defect detector 100 at a linear velocity v) comprises a defect-containing portion 195 having defects 85 in the form of small "globules" or "slubs" caused by impurities adhering to the surface of the fibrous structure 110. In this figure, the cross-sectional diameters calculated at times t2, t3, t4 and t5 indicate the presence of "globules" or "bamboo joint" defects 85 caused by impurities.

Focusing on the magnitude of the cross-sectional diameter of the fibrous structure 110 within the defect-containing portion 195, FIG. 6B shows where (i) the magnitude increases abruptly at time t3 relative to time t2 (a magnitude surface defect count that is significantly greater than zero occurs at time t 3), (ii) the magnitude increases only slightly at time t4 relative to time t3 (a magnitude surface defect count increases slightly at time t4 relative to time t 3), and then (iii) the magnitude decreases abruptly at time t5 relative to time t4 (a magnitude surface defect count that is zero occurs at time t 5). This pattern of abrupt and significant increases in the surface defect count at time t3, combined with the abrupt decrease back to zero in the surface defect count at time t5, indicates the presence of small "globule" or "bamboo joint" defects caused by recently introduced impurities.

Focusing on the slope of the cross-sectional diameter of the fibrous structure 110 within the defect-containing portion 195, FIG. 6B shows where (i) the slope increases at time t3 relative to time t2 (a slope surface defect count greater than zero occurs at time t 3), (ii) the slope decreases to near zero at time t4 relative to time t3 (a slope surface defect count of about zero occurs at time t 4), and then (iii) the slope returns to zero at time t5 relative to time t4 (a slope surface defect count of zero occurs at time t 5). This pattern of increasing the slope surface defect count at time t3, combined with the abrupt decrease in slope surface defect count at time t4 and the decrease in slope surface defect count at time t5 back to zero, indicates the presence of a "bead" or "slub" defect caused by the recently introduced impurity.

Focusing on the curvature of the cross-sectional diameter of the fibrous structure 110 within the defect-containing portion 195, FIG. 6B shows where (i) the curvature increases at time t3 relative to time t2 (a curvature surface defect count greater than zero occurs at time t 3), (ii) the curvature decreases to near zero at time t4 relative to time t3 (a curvature surface defect count near zero occurs at time t 4), and then (iii) the curvature remains zero at time t5 relative to time t4 (a zero curvature surface defect count occurs at time t 5). This pattern of increase in curvature surface defect count at time t3, combined with the decrease in curvature surface defect count at times t4 and t5 to zero, indicates the presence of "globule" or "slub" defects caused by the recently introduced impurities.

Fig. 6C shows the locations of cross-sectional measurements taken on the fibrous structure 110 at regular intervals from time t1 to t 8. The fibrous structure 110 (passing linearly through the defect detector 100 at a linear velocity v) comprises defect-containing portions 195 having defects 95 in the form of elongated or enlarged "globules" or "bamboo joints" caused by the accumulation or formation of impurities adhering to the surface of the fibrous structure 110. In this figure, the cross-sectional diameters calculated at times t2, t3, t4 and t5 indicate the presence of "globule" or "bamboo joint" defects 95 caused by impurities.

Focusing on the magnitude of the cross-sectional diameter of the fibrous structure 110 within the defect-containing portion 195, FIG. 6C shows where (i) the magnitude increases slightly at time t3 relative to time t2 (a magnitude surface defect count slightly greater than zero occurs at time t 3), (ii) the magnitude increases more significantly at time t4 relative to time t3 (a magnitude surface defect count increases significantly at time t4 relative to time t 3), and then (iii) the magnitude decreases at time t5 relative to time t4 (a magnitude surface defect count slightly greater than zero occurs at time t 5). This slight increase pattern of the amplitude surface defect count at time t3, combined with the increase in the amplitude surface defect count at time t4 and the decrease in the amplitude surface defect count at time t5, indicates the presence of elongated or enlarged "globules" or "slubs" caused by the accumulation or formation of impurities.

Focusing on the slope of the cross-sectional diameter of the fibrous structure 110 within the defect-containing portion 195, FIG. 6C shows where (i) the slope increases at time t3 relative to time t2 (a slope surface defect count greater than zero occurs at time t 3), (ii) the slope decreases to near zero at time t4 relative to time t3 (a slope surface defect count near zero occurs at time t 4), and then (iii) the slope increases again at time t5 relative to time t4 (a slope surface defect count greater than zero occurs at time t 5). This pattern of increasing the slope surface defect count at time t3, combined with the sudden decrease of the slope surface defect count to near zero at time t4, and the increase of the slope surface defect count at time t5, indicates the presence of elongated or enlarged "globules" or "slubs" caused by the accumulation or formation of impurities.

Focusing on the curvature of the cross-sectional diameter of the fibrous structure 110 within the defect-containing portion 195, FIG. 6C shows where (i) the curvature increases at time t3 relative to time t2 (a curvature surface defect count greater than zero occurs at time t 3), (ii) the curvature decreases to near zero at time t4 relative to time t3 (a curvature surface defect count near zero occurs at time t 4), and then (iii) the curvature increases again at time t5 relative to time t4 (a curvature surface defect count greater than zero occurs at time t 5). This pattern of increase in curvature surface defect count at time t3, combined with the sudden decrease in curvature surface defect count at time t4 to near zero and the increase in curvature surface defect count at time t5, indicates the presence of elongated or enlarged "balls" or "knots" caused by the accumulation or formation of impurities.

In general, by increasing the sampling rate of the measurements, the ability to distinguish and classify different defects contained in the fibrous structure that linearly passes through the at least one defect detector may be increased. Thus, for example, if the number of measurement intervals in fig. 6A-6C is doubled, such that 16 measurements are made on the same length of fibrous structure 110, the ability to distinguish and classify different defects may be improved, as the pattern may be detected with a higher resolution.

In some embodiments, the defect detection method may include the additional step of varying the linear velocity of the fibrous structure based on the surface defect signal. For example, the linear velocity of the fibrous structure may be reduced to increase the number of measurement intervals-thereby increasing the sensitivity and improving the ability to distinguish and classify different defects. In this regard, the defect detection methods of the present disclosure may use at least one speedometer to measure the linear velocity of the fibrous structure. In some embodiments, the fibrous structure may pass linearly through the at least one defect detector at a linear velocity of at least 300 meters per minute, while in other embodiments the linear velocity may be less than 10 centimeters per minute. In some embodiments, for example where the fibrous structure is a woven fibrous structure having a textured surface or a skein fibrous structure, the fibrous structure may pass linearly through the at least one detector at a linear velocity of less than 10 cm/min to at least 1 m/min.

In some embodiments, the defect detection method may include the additional step of varying the sampling rate at which the at least one cross-sectional diameter is measured based on the surface defect signal. For example, the sampling rate may be increased to increase the number of measurement intervals-thereby increasing the sensitivity and improving the ability to distinguish and classify different defects.

With respect to the reference signal (e.g., based on the amplitude, slope, and/or curvature of the cross-sectional diameter) used to generate the various surface defect signals, the reference signal may be a constant reference signal that is constant along the length of the fibrous structure, the reference signal may be a variable reference signal that varies at one or more points along the length of the fibrous structure, or a combination thereof.

The at least one defect detector may be in series with the at least one roller, the at least one extrusion apparatus configured to form the fibrous structure, the at least one braiding machine configured to form the fibrous structure, the at least one tensioning assembly configured to apply tension to the fibrous structure, the at least one finish applicator configured to apply a coating to the fibrous structure, the at least one godet assembly configured to stretch the fibrous structure, the at least one winding assembly configured to wind the fibrous structure on a spool, or a combination thereof. Other equipment commonly used to process, machine, and/or measure fibrous structures may also be in-line with the defect detector of the present disclosure.

Fig. 7 illustrates an apparatus for producing or processing a fibrous structure in which a plurality of defect detectors 205, 206, 207, 208, 209, and 210 (or an array of defect detectors described below) are positioned with a tensioning assembly 215, a finish applicator 220, a godet assembly 225, and a winding assembly 230. In this example, the fibrous structure 110 is passed linearly from a spool or upstream process 235 through a tensioning assembly 215 in series with the peripheral defect detectors 205 and 206, then through a first roller 240 and through a finish applicator 220 in series with the peripheral defect detectors 207 and 208, then through a second roller 245 and through a godet roller assembly 225 in series with the defect detector 209, then through a third roller 250 and into a winding assembly 230 that includes a dancer arm 255, a traverse guide assembly 260, and a finished spool 265. The upstream process 235 may include, for example, an extrusion, winding, or braiding process for producing the fibrous structure 110.

The inspection methods of the present disclosure may include the step of forming a fibrous structure by an extrusion process wherein at least one defect detector is in series with the extrusion apparatus. The inspection method of the present invention may further include the step of forming a fiber-containing structure by a braiding process, wherein at least one defect detector is in series with the braiding machine. The defect detector may also be located within the braiding apparatus, for example between at least one carrier spool (or carrier guide) and the winding shaft.

The detection method of the present invention may further comprise the step of modifying the operation of the extrusion apparatus, the braiding machine, the tensioning assembly, the finish applicator, the godet assembly, the winding assembly, the line speed, or a combination thereof, based on the surface defect signal. For example, if the method detects that the surface defect output begins to increase immediately downstream of the finish applicator 220, the operation of the finish applicator may be modified by decreasing the linear velocity v of the fibrous structure or by changing the operating parameters of the finish applicator 220 to decrease the surface defect output.

A defect detector array comprising at least two defect detectors in series may also be used in the methods of the present disclosure. Fig. 8 illustrates an embodiment in which defect detector array 270 is located downstream of braiding machine 275 and upstream of downstream process 280, such as tensioning assembly 215, finish applicator 220, godet assembly 225, and/or winding assembly 230 described above. In the example of fig. 8, defect detector array 270 includes two defect detectors 285 and 290 in series. In some embodiments, the defect detectors in the defect detector array may be rotated by a detector offset angle relative to each other such that different contour images of the fibrous structure are detected by at least two detectors. The detector offset angle may range from 1 deg. to less than 360 deg..

The defect detector of the present disclosure may include a multi-axis defect detector capable of simultaneously measuring a plurality of cross-sectional diameters of a fibrous structure from different directions.

In an embodiment, the dual-axis defect detector comprises two projectors for transmitting light onto the fibrous structure and two light receivers for detecting a profile image of the fibrous structure. The two projectors may comprise a projector a for transmitting light a onto the surface a of the fibrous structure and a projector B for transmitting light B onto the surface B of the fibrous structure. The two light receivers may comprise a light receiver a for detecting a contour image a of the fibrous structure and a light receiver B for detecting a contour image B of the fibrous structure. In this case, projector a is optically aligned with light receiver a and projector B is optically aligned with light receiver B. Projector a and projector B rotate relative to each other by a projector offset angle and light receiver a and light receiver B rotate relative to each other by a light receiver offset angle. In some embodiments, the projector offset angle and the optical receiver offset angle may independently be in the range of 5 ° to 175 °.

Fig. 9 shows a defect detector array 295 comprising two dual-axis defect detectors a 300 and β 305 mounted in series relative to a fibrous structure 110 moving linearly through the defect detector array 295 at a linear velocity v. Each of the two dual-axis defect detectors α300 and β305 includes a projector a310 and a projector B315, and a light receiver a320 and a light receiver B325. Projector a310 is optically aligned with light receiver a320 and projector B315 is optically aligned with light receiver B325. In the dual-axis defect detector α300, the projector a310 and the projector B315 are rotated relative to each other by the projector offset angle ΔΦ _α Wherein ΔΦ _α ＝Φ ¹ _α -Φ ² _α . In the dual-axis defect detector β305, the projector a310 and the projector B315 are rotated relative to each other by a projector offset angle ΔΦ _β Wherein ΔΦ _β ＝Φ ¹ _β -Φ ² _β 。

In the embodiment of fig. 9, the dual-axis defect detectors α300 and β305 are also offset from each other by a detector offset angle of about 90 ° and are separated by a linear separation distance d330. In some embodiments, the detector offset angle may range from 1 ° to less than 360 °. In some embodiments, the separation distance d may range from about 1mm to about 100mm. Other embodiments of the present disclosure may employ a defect detector array having at least three defect detectors arranged in series.

Fiber-containing structure

The present disclosure also relates to fibrous structures obtained by the defect detection methods disclosed herein. As described above, the fiber-containing structure may include a wire, braid, or core-sheath structure having a braided or laid sheath. The twist of the yarn may be less than 10 turns/m, even less than 1 turn/m.

The term "core-sheath structure" as used herein describes a cord-like structure having a braided strand sheath (jacket) at least partially surrounding a central core. Fig. 1C and 1D show a core-sheath structure with a braided sheath and a twisted sheath, respectively.

The fibrous structures of the present invention may comprise a core-sheath structure having a shape-controlled (flat) low thickness sheath that more closely conforms to the outer surface of the core to control the texture and surface roughness of the outer surface of the core-sheath structure. Such shape-controlled core-sheath structures include those described in U.S. provisional application No. 63/044418, filed on even 26, 6, 2020, the entire contents of which are incorporated herein by reference.

The fibrous structure of the present invention may also comprise a braided cord of varying cross-sectional area. Such varying cross-sectional area braided cords include those described in U.S. provisional application No. 63/069182 filed on even 24/8/2020, the entire contents of which are incorporated herein by reference.

In some embodiments, the surface coverage of the braided sheath on the core is at least 85%. In other embodiments, the surface coverage may range from about 25% to about 100%. In other embodiments, the surface coverage may be in excess of 100% such that adjacent strands at least partially overlap each other. In some embodiments, the surface coverage may be in the range of about 25% to about 150%. For example, the surface coverage may range from about 50% to about 125%, or from about 75% to about 110%, or from about 85% to about 105%, or from about 90% to about 100%.

In some core-sheath structures, the surface coverage may be significantly less than 100% (due to deliberate gaps), or significantly more than 100% (due to strand overlap of the sheath (sheath)). Such an embodiment may be advantageous, for example, when a sheath (sheath) is advantageous to obtain a higher surface roughness (due to the presence of gaps and/or protrusions) or when additional protection of the core is required (due to the presence of overlapping strands).

The number of picks of the braided sheath in a relaxed state (i.e., a natural resting state in which no tension is applied to the core-sheath structure) may be in the range of 30 to 3000 filament unit intersections per meter. In other embodiments, the number of picks of the braided sheath may be in the range of about 30 to 3000 crossover points per meter or about 50 to about 2000 crossover points per meter or about 50 to 1000 crossover points per meter in the relaxed state.

The number of strands (ends) of the braided sheath depends on the requirements of the core-sheath structure and the ability of the braiding apparatus. Depending on the particular application, a number of strands (ends) of 3 to over 200 may be used. In some embodiments, the number of strands (ends) of the braided sheath may be in the range of 4 to 96 ends, and in other applications it may be appropriate to limit the number of strands (ends) to about 24 ends. For example, the number of strands (ends) of the core-sheath structure of the present disclosure may range from 4 to 24 ends, or from 4 to 16 ends, or from 4 to 12 ends, or from 4 to 8 ends, or from 4 to 6 ends. In medical applications, the core-sheath structure of the present invention is typically 4 to 24 terminal.

The braiding angle of the braided sheath in the relaxed state is typically in the range of about 5 ° to about 85 °. In other embodiments, the braiding angle of the S-strands and Z-strands of the braided sheath in the relaxed state may be in the range of about 5 ° to about 60 °, or about 10 ° to about 75 °, or about 15 ° to about 60 °, or about 20 ° to about 45 °, or about 5 ° to 45 °.

The choice of braiding angle has a profound effect on the performance of the core-sheath structure used as the fibrous structure of the present invention. For example, as the load-bearing fibers of the jacket (sheath) are more aligned with the load direction, decreasing the braid angle increases the modulus and/or strength of the resulting core-sheath structure. The braid angle selection may also be used to control the load distribution between the core and the sheath (sheath). In some embodiments, load distribution balance between the core and sheath (sheath) is important to obtain a core-sheath structure with optimal tensile strength and durability.

The fibrous structure of the present invention may comprise a core-sheath structure comprising a core and a braided sheath of strands surrounding the core, wherein the braided sheath comprises strands having a braiding angle of 5 ° or greater in a relaxed state and the strands having a braiding angle of 5 ° or greater in a relaxed state comprise at least one shaped filament strand. Such core-sheath structures may be produced such that the shaped filament strands are untwisted strands having a twist of less than 1 revolution per meter, the shaped filament strands have a cross-sectional aspect ratio of at least 3:1 as measured in the braided sheath, at least a portion of the braided sheath has a thickness of about 20 to about 200 μm, and/or the braided sheath comprises synthetic fibers having a tensile strength of greater than 12 cN/dtex.

The core-sheath structure of the present invention includes embodiments wherein the braided sheath comprises at least one strand of untwisted formed filaments having a twist of less than 0.75 turns/meter, or less than 0.5 turns/meter, or less than 0.25 turns/meter.

In some embodiments, the cross-sectional aspect ratio of the shaped strand is in the range of 3:1 to 50:1, or in the range of 3:1 to 20:1, or in the range of 4:1 to 15:1, or in the range of 5:1 to 10:1. In other cases, the cross-sectional aspect ratio of the shaped strand may be in the range of about 3:1 to about 50:1 (ovality about 68-98%), or in the range of about 4.1:1 to about 50:1 (ovality about 75.5-98%), or in the range of about 5.6:1 to about 50:1 (ovality about 82-98%), or in the range of about 8:1 to about 22.2:1 (ovality about 87.5-95.5%).

The thickness of at least a portion of the braided sheath may range from about 16 μm to about 250 μm, or from about 40 μm to about 200 μm, or from about 50 μm to about 175 μm, or from about 60 μm to about 150 μm, or from about 50 μm to about 125 μm.

The fibrous structures of the present invention may comprise synthetic fibers having a tensile strength greater than 12 cN/dtex. The synthetic fibers may have a tensile strength of at least 13cN/dtex or at least 15cN/dtex or at least 20 cN/dtex. In some embodiments, the synthetic fibers contained in the braided sheath may have a tensile strength from 13cN/dtex to 50cN/dtex or from 15cN/dtex to 45 cN/dtex.

In addition to synthetic fibers having a tensile strength greater than 12cN/dtex, the fiber-containing structures of the present invention may include other synthetic and non-synthetic fibers and filaments having a tensile strength in the range of about 1cN/dtex to about 30 cN/dtex. For example, some fibrous structures may comprise at least one synthetic fiber having a tensile strength greater than 12cN/dtex and at least one synthetic or non-synthetic fiber having a tensile strength less than 12 cN/dtex.

The fibrous structures of the present invention may also have a maximum (outer) diameter of from about 15 μm to about 20 mm. In other embodiments, the outer diameter may be in the range of about 20 μm to about 8mm or about 30 μm to about 5mm or about 50 μm to about 3mm or about 50 μm to about 1 mm.

A wide variety of core dimensions may also be used in the core-sheath structures of the present disclosure. For example, the maximum diameter of the core may be in the range of about 10 μm to about 20 mm. In other embodiments, the maximum diameter of the core may be in the range of about 15 μm to about 10mm or about 25 μm to about 5mm or about 50 μm to about 1mm or about 50 μm to about 500 μm.

The core-sheath structure of the present invention may employ a twisted or untwisted core and a monofilament core. In some embodiments, the core comprises at least two core strands twisted together with a twist of greater than 0 to 1600 turns/meter. The number of core strands included in the twisted or untwisted core may be in the range of 1 to 500 and the twist of the core or core strands used to produce the multi-strand core may be in the range of 1 to 1600 turns/meter. Combinations of twisted, untwisted, and/or braided filaments can also be used to produce cores in the core-sheath structures of the present disclosure.

Embodiments of the present disclosure include a core-sheath structure comprising a circular core having a circular cross-section and a braided sheath comprised of shaped strands, wherein the flattening factor of the shaped strands is in the range of about 0.05 to about 0.45. In other embodiments, the flattening factor may range from about 0.1 to about 0.35, or from about 0.10 to about 0.30, or from about 0.1 to about 0.25.

In some embodiments, the core in the core-sheath structure is a surface treated core. For example, the core component surface may be corona or plasma treated prior to application of the braided sheath. Such treatment may create surface imperfections or alterations that enhance the contact (surface interactions) between the core and the inner surface of the braided sheath, further enhancing the interaction between the core and the braided sheath.

Another aspect of the present disclosure relates to the proportion of shaped strands used in braiding the fibrous structure. In some embodiments, all of the strands used in the braiding step are shaped strands, while in other embodiments, only a small portion of the strands used in the braiding step are shaped strands. For example, in some embodiments, all S strands woven in the left hand direction are forming strands, while all Z strands woven in the right hand direction are non-forming strands, which are not subjected to a forming step that occurs prior to the weaving step, and vice versa. In still other embodiments, only a small portion of one or both of the S-strands and Z-strands may be shaped strands. Embodiments of the present disclosure include a core-sheath structure that includes only one shaping strand in the braided sheath, or all (100%) shaping strands in the braided sheath, or any combination between one shaping strand and 100% shaping strands in the braided sheath.

The fibrous structure of the present invention further comprises a core-sheath structure wherein the braided sheath is a hybrid sheath comprising at least one shaped strand having a cross-sectional aspect ratio of at least 3:1 and at least one non-shaped strand having a cross-sectional aspect ratio of less than 2:1. For example, in some embodiments, the braided sheath is a hybrid sheath comprising at least one shaped strand having a cross-sectional aspect ratio of at least 3:1 and at least one twisted (non-shaped) strand having a twist of greater than 0 to 1600 turns/meter. As described above, twisted tows (i.e., twisted strands) are more rigid and less formable than untwisted tows.

The core-sheath structure used as the fibrous structure of the present invention may further comprise a triaxial braided sheath comprising longitudinal strands having a braiding angle of less than 5 ° in a relaxed state, in addition to the S-strands braided in the left-hand direction and the Z-strands braided in the right-hand direction. In some embodiments, the triaxial braided sheath may include at least one shaped longitudinal strand formed by shaping at least one longitudinal strand prior to braiding the plurality of strands. For example, the triaxial braided sheath of the present invention may include one shaped longitudinal strand, all shaped longitudinal strands or any combination therebetween, in addition to the S-strands and Z-strands.

The fibrous structures of the present disclosure may also comprise additional components, such as lubricants, fibers, surface-coated filaments, or combinations thereof. The lubricant used in the fibrous structure of the present invention may comprise at least one of a lubricating filament and a lubricating fiber. The surface-coated filaments may include a crosslinked or non-crosslinked silicone polymer as the surface coating.

The fibrous structures of the present invention may have a linear density of from about 30 denier to about 10000 denier. In other embodiments, the linear density of the core-sheath structure may be from about 40 denier to about 4500 denier, or from about 50 denier to about 4000 denier, or from about 100 denier to about 3000 denier, or from about 70 denier to about 2000 denier, or from about 80 denier to about 1500 denier, or from about 90 denier to about 1000 denier.

The fibrous structures of the present disclosure may comprise organic fibers. The chemical make-up of the fibers included in the fiber-containing structures of the present disclosure may be any high performance polymer known to provide a combination of high tensile strength, high toughness, and low creep, and may be selected from, but is not limited to, liquid crystalline polyester filaments, aramid filaments, copolyaramid filaments, polyetheretherketone filaments, poly (p-Phenylene Benzobisoxazole) (PBO) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, high strength polyvinyl alcohol filaments, polyhydroquinone diimidazole pyridine (PIPD) filaments, and combinations thereof, to name a few.

Polyhydroquinone Diimidazopyridine (PIPD) filament fibers are based on polymers of the following repeating units:

the fiber-containing structure of the present disclosure may include at least one selected from the group consisting of liquid crystalline polyester filaments, aramid filaments, copolyaramid filaments, polyetheretherketone filaments, poly (p-phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, poly hydroquinone diimidazole pyridine filaments, and high strength polyvinyl alcohol filaments. In other embodiments, at least two of these materials may be included in the fibrous structure.

In some embodiments, the fiber-containing structure may comprise at least one fiber selected from the group consisting of liquid crystalline polyester fibers, aramid fibers, PBO fibers, ultra high molecular weight polyethylene fibers, and high strength polyvinyl alcohol fibers. In other embodiments, the shaped and/or non-shaped strands of the braided sheath may be selected from liquid crystalline polyester fibers and aramid fibers, especially liquid crystalline polyester fibers.

In some embodiments, the core-sheath structure of the present invention may include a core including at least one selected from the group consisting of liquid crystalline polyester filaments, aramid filaments, copolyaramid filaments, polyetheretherketone filaments, poly (phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, polypropylene filaments, high modulus polyethylene filaments, polyethylene terephthalate filaments, polyamide filaments, and high strength polyvinyl alcohol filaments.

The polymeric units may include those shown in table 1.

TABLE 1

(wherein X in the formula is selected from the following structures)

(wherein m=0 to 2, y=a substituent selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an aralkyl group, an alkoxy group, an aryloxy group and an aralkoxy group)

Regarding the polymerization units shown in table 1 above, the number of Y substituents is equal to the maximum number of substitutable positions in the ring structure, and each Y independently represents a hydrogen atom, a halogen atom (e.g., fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), an alkyl group (e.g., an alkyl group having 1 to 4 carbon atoms such as methyl, ethyl, isopropyl, or tert-butyl), an alkoxy group (e.g., methoxy, ethoxy, isopropoxy, n-butoxy, etc.), an aryl group (e.g., phenyl, naphthyl, etc.), an aralkyl group [ benzyl (phenylmethyl), phenethyl (phenethyl), etc. ], an aryloxy group (e.g., phenoxy, etc.), an aralkoxy group (e.g., benzyloxy, etc.), or a mixture thereof.

The liquid crystal polyester fiber may be obtained by melt spinning a liquid crystal polyester resin. The spun fibers may be further heat treated to enhance mechanical properties. The liquid crystalline polyesters may be composed of recurring polymeric units, for example derived from aromatic diols, aromatic dicarboxylic acids or aromatic hydroxycarboxylic acids. The liquid crystalline polyester may optionally further comprise polymerized units derived from aromatic diamines, aromatic hydroxylamines and/or aromatic aminocarboxylic acids.

More specific polymerized units are illustrated in the structures shown in tables 2-4 below.

When the polymerized units in the formula are units that can represent various structures, two or more units may be used in combination as polymerized units constituting the polymer.

In the polymerization units of tables 2, 3 and 4, n is an integer of 1 or 2, and the respective units n=1, n=2 may exist alone or in combination; y1 and Y2 each independently may be a hydrogen atom, a halogen atom (e.g., a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), an alkyl group (e.g., an alkyl group having 1 to 4 carbon atoms such as methyl, ethyl, isopropyl, or tert-butyl), an alkoxy group (e.g., methoxy, ethoxy, isopropoxy, n-butoxy, etc.), an aryl group (e.g., phenyl, naphthyl, etc.), an aralkyl group (benzyl (phenylmethyl), phenethyl (phenethyl), etc.), an aryloxy group (e.g., phenoxy, etc.), an aralkoxy group (e.g., benzyloxy, etc.), or a mixture thereof. Among these groups, Y is preferably a hydrogen atom, a chlorine atom, a bromine atom or a methyl group.

TABLE 2

TABLE 3 Table 3

TABLE 4 Table 4

Z in (14) of Table 3 may include a divalent group represented by the following formula.

In some embodiments, the liquid crystalline polyester may be a combination comprising a naphthalene skeleton as a polymeric unit. In particular, it may comprise polymerized units (a) derived from hydroxybenzoic acid and polymerized units (B) derived from hydroxynaphthoic acid. For example, unit (a) may have formula (a), and unit (B) may have formula (B). The ratio of the unit (A) to the unit (B) may be in the range of 9/1 to 1/1, preferably 7/1 to 1/1, more preferably 5/1 to 1/1, from the viewpoint of improving the melt moldability.

The total amount of the polymerized units (a) and the polymerized units (B) may be, for example, about 65 mol% or more, or about 70 mol% or more, or about 80 mol% or more, based on the total polymerized units. In some embodiments, the braided sheath may comprise a liquid crystalline polyester comprising about 4 to about 45 mole% polymerized units (B) in the polymer.

The melting point used herein is the main absorption peak temperature measured and observed by a Differential Scanning Calorimeter (DSC) (e.g., "TA3000" manufactured by METLER Co., ltd.) according to the JIS K7121 test method. Specifically, 10 to 20mg of the sample was used in the above DSC apparatus, and after the sample was packaged in an aluminum pan, nitrogen was allowed to flow as a carrier gas at a flow rate of 100 cc/min, and the endothermic peak at heating at a rate of 20 ℃/min was measured. Depending on the type of polymer, when no distinct peak occurs in the first round of DSC measurement, the temperature is raised to a temperature 50 ℃ higher than the intended flow temperature at a ramp rate (or heating rate) of 50 ℃/min, then melted completely at the same temperature for 3 minutes, and cooled further to 50 ℃ at a cool down rate (or cooling rate) of-80 ℃/min. Thereafter, the endothermic peak may be measured at a temperature increase rate of 20 ℃/min.

The commercially available LCP's contained in the braided sheath of the present invention may include those manufactured by KURARAY Co., ltdHT BLACK, manufactured by KURARAY Co., ltd./i>Manufactured by HT, toray CoMonofilament manufactured by ZEUS and +.A manufactured by KB SEIREN Co., ltd>

Liquid crystalline polyesters may be used in the core-sheath structures of the present disclosure, alone or in combination.

According to the present invention, "aramid fiber" means a polyamide fiber having high heat resistance and high strength, which comprises a molecular skeleton composed of aromatic (benzene) rings. Aramid fibers can be classified into para-aramid fibers and meta-aramid fibers according to their chemical structure, with para-aramid fibers preferably included in some braided sheaths of the present invention.

Examples of commercially available aramid and copolyaramid fibers include para-aramid fibers, such as those manufactured by DuPontKolon Co Ltd +.>And Teijin LimitedAnd->And meta-aramid fibers, e.g., manufactured by DuPontAnd +.f. manufactured by Teijin Inc>

When included in the fiber-containing structures of the present disclosure, the aramid fibers may be used alone or in combination. In some embodiments, the filaments included in the fibrous structure may comprise copolymer aramid filaments. For example, in some embodiments, the fiber-containing structure comprises copolymerized styrene/3, 4' -oxydiphenylene terephthalamide filaments.

Such materials are commonly referred to asAvailable from Teijin.

Poly (p-phenylene benzobisoxazole) (poly (p-phenylene-2, 6-benzobisoxazole) (PBO) fibers are manufactured by Toyo-yo, inc.)AS and->HM。

The fiber-containing structures of the present invention may also be formed from Polyetheretherketone (PEEK) materials, such as VICTREX ^TM PEEK polymer. In some embodiments, high dpf PEEK polymerization is usedThe composition as a component of the fibrous structure may impart improved tensile properties to the fibrous structure.

The inherent viscosity of the ultra high molecular weight polyethylene fibers used in some fiber-containing structures of the invention may be in the range of about 5.0 or about 7.0 or about 10 to about 30 or about 28 or about 24 dL/g. When the intrinsic viscosity of the "ultra-high molecular weight polyethylene fiber" is in the range of about 5.0 to about 30dL/g, a fiber having good dimensional stability is obtained.

The weight average molecular weight of the "ultra-high molecular weight polyethylene fiber" may be about 700000 or about 800000 or about 900000 to about 8000000 or about 7000000 or about 6000000. When the weight average molecular weight of the "ultra-high molecular weight polyethylene fiber" is in the range of about 700000 to about 8000000, high tensile strength and elastic modulus can be obtained.

Since it is difficult to determine the weight average molecular weight of the "ultra high molecular weight polyethylene fiber" using the GPC method, the weight average molecular weight can be determined based on the above-described intrinsic viscosity value according to the following equation mentioned in "Polymer Handbook Fourth Edition, chapter 4 (John Wiley, published 1999)". Weight average molecular weight= 5.365 ×104× (intrinsic viscosity) 1.37.

In some embodiments, it is preferred that the repeating units of "ultra high molecular weight polyethylene fibers" comprise essentially ethylene. However, in addition to homopolymers of ethylene, copolymers of ethylene with small amounts of other monomers, such as alpha-olefins, acrylic acid and its derivatives, methacrylic acid and its derivatives, and vinylsilanes and its derivatives, may also be used. The polyethylene fibers may have a partially crosslinked structure. The polyethylene fiber may also be a blend of high density polyethylene and ultra high molecular weight polyethylene, a blend of low density polyethylene and ultra high molecular weight polyethylene, or a blend of high density polyethylene, low density polyethylene and ultra high molecular weight polyethylene. The polyethylene fiber may be a combination of two or more ultra-high molecular weight polyethylenes having different weight average molecular weights, or a combination of two or more polyethylenes having different molecular weight distributions.

Commercially available "ultra-high molecular weight polyethylene fibers" include those manufactured by Toyo-yo, incSK60,SK,SK60 and->SK71 and SPECTRAFIBER +.f manufactured by Honeywell Co., ltd>And a SPECTRA FIBER 1000.

These "ultra-high molecular weight polyethylene fibers" may be used alone or in combination.

The properties and characteristics of the fibrous structure of the present invention may be altered and controlled by applying the finishing composition to the core and/or braided sheath. For example, the fiber-containing structure may comprise filaments, fibers, or strands having a coating of a crosslinked silicone polymer, a non-crosslinked silicone polymer, or a long chain fatty acid. Suitable long chain fatty acids may include stearic acid.

The use of cross-linked silicone polymers can provide advantageous property enhancements to the tensile strength of the fibrous structures of the present invention.

In general, there are three crosslinking reaction methods available for preparing silicone resins: 1) Peroxide curing, wherein thermal activation of the polymerization occurs under formation of peroxide radicals; 2) Condensing in the presence of a tin salt or a titanium alkoxide catalyst under the influence of heat or moisture; and 3) addition reaction chemistry catalyzed by platinum or rhodium complexes, which may be temperature initiated or photoinitiated.

The crosslinked silicone coating may enhance the moisture resistance of the coated strand and may also enhance the lubricity of the strand such that the response of the braid is more effective when the core-sheath structure is subjected to longitudinal stress than an uncoated structure that may need to overcome frictional interactions.

The coating compositions of the present invention may be applied by surface coating techniques known to those skilled in the art. These surface coating techniques may include simply pumping a finish solution through a finish conduit where the fibers come into contact with the finish and wick into the fiber bundle by capillary action. Alternatively, other techniques may include spray, roll or immersion application techniques, such as dip coating. Subsequent treatment of the fibers with the applied finish solution may include contact with one or more rollers in order to set the finish and/or to affect the degree of crosslinking in the finish formulation. The rollers may or may not be heated. The coating composition may then be cured to cause crosslinking of the crosslinkable silicone polymer. When heat curing is used, the temperature may be about 20 ℃ or about 50 ℃ or about 120 ℃ to about 200 ℃ or about 170 ℃ or about 150 ℃. The curing temperature may be determined by the thermal stability of the filaments, fibers or strands and the crosslinking system actually used.

The degree of crosslinking achieved can be controlled to provide varying degrees of flexibility or other surface characteristics to the filaments, fibers or strands. The degree of crosslinking can be determined by the method described in US8881496B2, wherein the coating is extracted with a solvent that dissolves the monomers but not the crosslinked polymer. The degree of crosslinking can be determined by the weight difference before and after extraction.

The degree of crosslinking may be at least about 20%, or at least about 30%, or at least about 50%, based on the total weight of the coating. The maximum degree of crosslinking may be about 100%. The weight of the crosslinked coating may be from about 1 wt% to about 20 wt% or about 10 wt% or about 5 wt% based on the total weight of the filaments, fibers or strands.

In some embodiments, the maximum cross-sectional diameter of the fibrous structure may be in the range of about 15 μm to about 20 mm. In other embodiments, the maximum diameter may be in the range of about 20 μm to about 5mm, or about 30 μm to about 4mm, or about 40 μm to about 3.5mm, or about 50 μm to about 3mm, or about 50 μm to about 2 mm. The average cross-sectional diameter of the fibrous structure may be in the range of about 20 μm to about 10 mm.

The fibrous structures of the present invention can be designed to meet a variety of properties including fracture toughness. In some embodiments, the fracture toughness is at least 15cN/dtex. In other embodiments, the tenacity at break of the cord may be in the range of about 4cN/dtex to about 40cN/dtex, or about 13cN/dtex to about 31cN/dtex, or about 15cN/dtex to about 26 cN/dtex.

The fibrous structure of the present invention comprises a tensioning member useful in a variety of applications including medical cords. For example, the fibrous structures of the present disclosure include sutures, catheter navigation cables and assemblies, steering cables and assemblies, device deployment control cables and assemblies, and torque and tension transmission cables and assemblies, to name a few.

The fibrous structure of the present invention may comprise cords having a linear density in the range of about 30 denier to about 10000 denier. In other embodiments, the linear density may range from about 40 denier to about 4500 denier, or from about 50 denier to about 4000 denier, or from about 100 denier to about 3000 denier, or from about 70 denier to about 2000 denier, or from about 80 denier to about 1500 denier, or from about 90 denier to about 1000 denier.

Device for detecting defects in a moving fibrous structure

The present disclosure also relates to an apparatus for detecting defects in a moving fibrous structure. Such a device may include: (A) An extrusion apparatus configured to form a fibrous structure, a braiding machine configured to form a fibrous structure, a tensioning assembly configured to apply tension to the fibrous structure, a finish applicator configured to apply a coating to the fibrous structure, a godet assembly configured to stretch the fibrous structure, a winding assembly configured to wind the fibrous structure onto a spool, a roller, or a combination thereof; (B) A defect detector configured to measure at least one cross-sectional diameter of the fibrous structure by: transmitting light onto the fiber-containing structure with a projector, detecting a profile image of the fiber-containing structure with a light receiver, and calculating a cross-sectional diameter based on a decrease in an amount of light detected by the light receiver relative to a total amount of light transmitted by the projector; and (C) a processor configured to compare the at least one diameter signal, optionally the at least one signal processed diameter signal, or a combination thereof, obtained from the defect detector to at least one reference signal to obtain at least one surface defect signal of the surface defect output versus the length of the fibrous structure, wherein the defect detector measures the at least one cross-sectional diameter as the fibrous structure passes linearly through the defect detector.

The apparatus of the present disclosure operates as described in the above methods and may be modified according to the above subject matter.

Examples

Embodiment [1] of the present disclosure relates to a method comprising: passing the fibrous structure linearly through at least one defect detector; measuring at least one cross-sectional diameter of the fibrous structure with a defect detector to obtain at least one diameter signal of diameter versus length of the fibrous structure; optionally, signal processing the diameter signal to obtain at least one signal processed diameter signal; and comparing the diameter signal, the signal processed diameter signal, or a combination thereof to at least one reference signal to produce at least one surface defect signal of the surface defect output versus the length of the fibrous structure, wherein: the defect detector measures the cross-sectional diameter of the fibrous structure by: transmitting light onto the fiber-containing structure with a projector, detecting a profile image of the fiber-containing structure with a light receiver, and calculating a cross-sectional diameter based on a decrease in an amount of light detected by the light receiver relative to a total amount of light transmitted by the projector; and at least one defect detector is in series with the extrusion apparatus configured to form the fibrous structure, the braiding machine configured to form the fibrous structure, the tensioning assembly configured to apply tension to the fibrous structure, the finish applicator configured to apply a coating to the fibrous structure, the godet assembly configured to stretch the fibrous structure, the winding assembly configured to wind the fibrous structure onto a spool, or a combination thereof.

Embodiment [2] of the present disclosure relates to the method of embodiment [1] wherein the fibrous structure is passed linearly through the at least one defect detector at a linear velocity of at least 300 meters per minute.

Embodiment [3] of the present disclosure relates to the methods of embodiments [1] and [2], wherein the fibrous structure is a woven fibrous structure or a skein fibrous structure, and the fibrous structure is passed linearly through the at least one detector at a linear velocity of at least 1 meter/min.

Embodiment [4] of the present disclosure relates to the method of embodiments [1] to [3], wherein the fiber-containing structure is a nonwoven fiber-containing structure having a twist of less than 1 revolution per meter, the fiber-containing structure is a woven fiber-containing structure, or the fiber-containing structure is a skein fiber-containing structure.

Embodiment [5] of the present disclosure relates to the method of embodiments [1] to [4], wherein the fiber-containing structure is a core-sheath structure comprising a core and a braided sheath of strands surrounding the core.

Embodiment [6] of the present disclosure relates to the method of embodiments [1] to [5], wherein the fiber-containing structure is a cord having a core-sheath structure including a braided sheath surrounding the core, and the braiding angle of the braided sheath in a relaxed state ranges from about 5 ° to about 85 °.

Embodiment [7] of the present disclosure relates to the method of embodiments [1] to [6], wherein the fiber-containing structure is a cord having a core-sheath structure including a braided sheath surrounding the core, and the braided sheath has a weft number of 6 to 3000 filament unit crossings per meter in a relaxed state.

Embodiment [8] of the present disclosure relates to the method of embodiments [1] to [7], wherein the fiber-containing structure is a cord having a core-sheath structure including a braided sheath surrounding the core, and the number of strands (ends) of the braided sheath is 3 to 24 ends.

Embodiment [9] of the present disclosure relates to the method of embodiments [1] to [8], wherein the fiber-containing structure is a cord having a skein structure comprising a nonwoven sheath surrounding a core.

Embodiment [10] of the present disclosure relates to the method of embodiments [1] to [9], wherein the fiber-containing structure comprises organic fibers.

Embodiment [11] of the present disclosure relates to the method of embodiments [1] to [10], wherein the fiber-containing structure comprises synthetic fibers having a tensile strength greater than 12 cN/dtex.

Embodiment [12] of the present disclosure relates to the method of embodiments [1] to [11], wherein the fiber-containing structure comprises at least one selected from the group consisting of: liquid crystalline polyester filaments, aramid filaments, copolyaramid filaments, polyetheretherketone filaments, poly (p-phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, poly hydroquinone diimidazole pyridine filaments, and high strength polyvinyl alcohol filaments.

Embodiment [13] of the present disclosure relates to the method of embodiments [1] to [12], wherein the fiber-containing structure comprises synthetic fibers and at least one of a lubricant, an artificial staple fiber, and a surface coating.

Embodiment [14] of the present disclosure relates to the method of embodiments [1] to [13], wherein the fiber-containing structure is a cord having a linear density of from about 30 to about 10000 denier.

Embodiment [15] of the present disclosure relates to the method of embodiments [1] to [14], wherein the fibrous structure has a maximum cross-sectional diameter ranging from about 20 μm to about 10mm.

Embodiment [16] of the present disclosure relates to the method of embodiments [1] to [15], wherein the average cross-sectional diameter of the fiber-containing structure ranges from about 20 μm to about 10mm.

Embodiment [17] of the present disclosure relates to the method of embodiments [1] to [16], further comprising forming the fibrous structure by an extrusion process, wherein the at least one defect detector is in series with the extrusion apparatus.

Embodiment [18] of the present disclosure relates to the method of embodiments [1] to [7], further comprising forming the fiber-containing structure by a braiding process, wherein the at least one defect detector is in series with the braiding machine.

Embodiment [19] of the present disclosure relates to the method of embodiments [1] to [18], further comprising forming the fiber-containing structure by a braiding process, wherein: the defect detector array is connected in series with the braiding machine so that the fiber-containing structure linearly passes through the defect detector array; the defect detector array includes at least two defect detectors in series; rotating the at least two defect detectors relative to each other by a detector offset angle such that different contour images of the fibrous structure are detected by the at least two defect detectors; and detector offset angles range from 1 deg. to less than 360 deg..

An embodiment [20] of the present disclosure relates to the method of embodiment [19], wherein the defect detector array comprises at least three defect detectors in series.

Embodiment [21] of the present disclosure relates to the methods of embodiments [19] and [20], wherein the separation distance between at least two defect detectors in the array of defect detectors is in the range of 1mm to 100mm.

Embodiment [22] of the present disclosure relates to the method of embodiments [19] to [21], wherein: the defect detector comprises two projectors for transmitting light onto the fibrous structure and two light receivers for detecting a profile image of the fibrous structure; the two projectors comprise a projector a for transmitting light a onto a surface a of the fibrous structure and a projector B for transmitting light B onto a surface B of the fibrous structure; the two light receivers comprise a light receiver A for detecting a contour image A containing the fiber structure and a light receiver B for detecting a contour image B containing the fiber structure; projector a is optically aligned with light receiver a and projector B is optically aligned with light receiver B; projector a and projector B rotate a projector offset angle relative to each other, and light receiver a and light receiver B rotate a light receiver offset angle relative to each other; and projector offset angles and optical receiver offset angles range from 5 ° to 175 °.

Embodiment [23] of the disclosure relates to the method of embodiments [1] to [22], wherein at least one defect detector is in series with the tensioning assembly.

Embodiment [24] of the present disclosure relates to the method of embodiments [1] to [23], wherein at least one defect detector is in series with the finish applicator.

Embodiment [25] of the present disclosure relates to the method of embodiments [1] to [24], wherein at least one defect detector is in series with the godet assembly.

Embodiment [26] of the present disclosure relates to the method of embodiments [1] to [25], wherein at least one defect detector is in series with the winding assembly.

Embodiment [27] of the present disclosure relates to the method of embodiments [1] to [26], wherein at least one defect detector is in series with at least one roller.

Embodiment [28] of the present disclosure relates to the method of embodiments [1] to [27], wherein: the measurement of the fibrous structure includes at least two defect detectors adjacently connected in series together as an array of defect detectors; and detector offset angles between adjacently positioned defect detectors in the defect detector array range from 1 deg. to less than 360 deg..

Embodiment [29] of the present disclosure relates to the method of embodiments [1] - [28], wherein: the measurement of the fibrous structure includes at least three defect detectors adjacently connected in series together as an array of defect detectors; and detector offset angles between adjacently positioned defect detectors in the defect detector array range from 1 deg. to less than 360 deg..

Embodiment [30] of the present disclosure is directed to the method of embodiments [1] to [29], wherein the defect detector is a multi-axis defect detector configured to measure at least two cross-sectional diameters of the fiber-containing structure such that an offset angle between the at least two cross-sectional diameters ranges from 5 ° to 175 °.

Embodiment [31] of the present disclosure relates to the method of embodiments [1] to [30], wherein: the defect detector comprises two projectors for transmitting light onto the fibrous structure and two light receivers for detecting a profile image of the fibrous structure; the two projectors comprise a projector a for transmitting light a onto a surface a of the fibrous structure and a projector B for transmitting light B onto a surface B of the fibrous structure; the two light receivers comprise a light receiver A for detecting a contour image A containing the fiber structure and a light receiver B for detecting a contour image B containing the fiber structure; projector a is optically aligned with light receiver a and projector B is optically aligned with light receiver B; projector a and projector B rotate a projector offset angle relative to each other, and light receiver a and light receiver B rotate a light receiver offset angle relative to each other; and projector offset angles and optical receiver offset angles range from 5 ° to 175 °.

An embodiment [32] of the present disclosure relates to the method of embodiments [1] to [31], wherein the projector comprises a laser diode or a light emitting diode.

Embodiment [33] of the present disclosure relates to the method of embodiments [1] to [32], wherein the light receiver is an active pixel sensor.

An embodiment [34] of the present disclosure relates to the method of embodiments [1] to [33], wherein the light receiver is an active pixel sensor comprising a photodiode image sensor, a Charge Coupled Device (CCD) image sensor, or a Complementary Metal Oxide Semiconductor (CMOS) image sensor.

An embodiment [35] of the present disclosure relates to the method of embodiments [1] to [34], further comprising imaging the surface of the fibrous structure with at least one imaging detector, wherein the imaging detector images the surface by illuminating the fibrous structure with imaging light and receiving a reflected image of the surface with an imaging receiver.

Embodiment [36] of the present disclosure relates to the method of embodiments [1] to [35], further comprising imaging the surface of the fibrous structure with at least one imaging detector, wherein: an imaging detector images the surface by illuminating the fiber-containing structure with imaging light and receiving a reflected image of the surface with an imaging receiver; and at least one imaging detector is in series with the extrusion apparatus, the braiding machine, the tensioning assembly, the finish applicator, the godet assembly, the winding assembly, or a combination thereof.

Embodiment [37] of the present disclosure relates to the method of embodiments [1] to [36], wherein the method does not comprise imaging the surface of the fibrous structure with an imaging detector that receives the reflected image of the surface.

Embodiment [38] of the present disclosure relates to the method of embodiments [1] to [37], wherein the measurement of the at least one cross-sectional diameter is performed at a sampling rate of at least 5000 samples per second.

Embodiment [39] of the present disclosure relates to the method of embodiments [1] to [38], wherein: at least one cross-sectional diameter measurement is performed at a sampling rate; adjusting the sampling rate of the at least one defect detector such that measurements are taken at constant intervals along the length of the fibrous structure; and the constant spacing ranges from 10nm to 1cm.

Embodiment [40] of the present disclosure relates to the method of embodiments [1] to [39], further comprising generating a surface defect grade of the fibrous structure based on the surface defect signal.

Embodiment [41] of the present disclosure relates to the method of embodiments [1] to [40], wherein the at least one surface defect signal comprises an amplitude surface defect count signal of amplitude surface defect count versus fiber-containing structure length, wherein: generating an amplitude surface defect count signal by comparing the diameter signal with a reference signal for the length of the fibrous structure having a maximum cross-sectional diameter; when the amplitude of the diameter signal is less than or equal to the maximum cross-sectional diameter at a particular point along the length of the fiber-containing structure, the amplitude surface defect count is zero; and when the amplitude of the diameter signal is greater than the maximum cross-sectional diameter at a particular point along the length of the fiber-containing structure, the amplitude surface defect count is greater than zero, such that the amplitude surface defect count greater than zero is a positive integer corresponding to the amplitude of the diameter signal being greater than a percentage of the maximum cross-sectional diameter.

An embodiment [42] of the present disclosure is directed to the method of embodiment [41] further comprising generating a surface defect grade of the fibrous structure based at least in part on the amplitude surface defect count signal.

An embodiment [43] of the present disclosure is directed to the methods of embodiments [41] and [42], further comprising classifying defects contained in the fibrous structure based at least in part on the amplitude surface defect count signal.

Embodiment [44] of the present disclosure relates to the method of embodiments [1] to [43], wherein the at least one surface defect signal comprises a slope surface defect count versus slope surface defect count signal comprising a fiber structure length, wherein: generating a slope surface defect count signal by comparing the signal-processed diameter signal with a reference signal containing a maximum first derivative of the fiber structure length of the diameter signal, wherein the signal-processed diameter signal is obtained by signal processing the diameter signal to obtain the first derivative of the diameter signal; the slope surface defect count is zero when the absolute value of the first derivative of the diameter signal is less than or equal to the maximum first derivative of the diameter signal at a particular point along the length of the fibrous structure; and when the absolute value of the first derivative of the diameter signal is greater than the largest first derivative of the diameter signal at a particular point along the length of the fibrous structure, the slope surface defect count is greater than zero such that the slope surface defect count greater than zero is a positive integer corresponding to the absolute value of the first derivative of the diameter signal being greater than a percentage of the largest first derivative of the diameter signal.

An embodiment [45] of the present disclosure relates to the method of embodiment [44], further comprising generating a surface defect grade of the fibrous structure based on the slope surface defect count signal.

Embodiment [46] of the present disclosure relates to the methods of embodiments [44] and [45], further comprising classifying defects contained in the fibrous structure based at least in part on the slope surface defect count signal.

Embodiment [47] of the present disclosure relates to the method of embodiments [1] to [46], wherein the at least one surface defect signal comprises a curvature surface defect count versus a curvature surface defect count signal comprising a fiber structure length, wherein: generating a curvature surface defect count signal by comparing the signal-processed diameter signal with a reference signal comprising a maximum second derivative of the fiber structure length of the diameter signal, wherein the signal-processed diameter signal is obtained by signal processing the diameter signal to obtain a second derivative of the diameter signal; when the absolute value of the second derivative of the diameter signal is less than or equal to the maximum second derivative of the diameter signal at a particular point along the length of the fibrous structure, the curvature surface defect count is zero; and when the absolute value of the second derivative of the diameter signal is greater than the maximum second derivative of the diameter signal at a particular point along the length of the fibrous structure, the curvature surface defect count is greater than zero such that the curvature surface defect count greater than zero is a positive integer corresponding to the absolute value of the second derivative of the diameter signal being greater than a percentage of the maximum second derivative of the diameter signal.

Embodiment [48] of the present disclosure relates to the method of embodiments [1] to [47], further comprising generating a surface defect rating for the fibrous structure based on the curvature surface defect count signal.

Embodiment [49] of the present disclosure is directed to the method of embodiments [1] to [48], further comprising classifying defects contained in the fibrous structure based at least in part on the curvature surface defect count signal.

Embodiment [50] of the present disclosure relates to the method of embodiments [1] to [49], wherein the reference signal is a constant reference signal that is constant along the length of the fibrous structure.

Embodiment [51] of the present disclosure relates to the method of embodiments [1] to [50], wherein the reference signal is a variable reference signal that varies at one or more points along the length of the fibrous structure.

Embodiment [52] of the present disclosure relates to the method of embodiments [1] to [51], further comprising: the linear velocity of the fibrous structure is measured using at least one speedometer.

Embodiment [53] of the present disclosure is directed to the method of embodiments [1] to [52], further comprising modifying the operation of the extrusion apparatus, the braiding machine, the tensioning assembly, the finish applicator, the godet assembly, the winding assembly, or a combination thereof based on the surface defect signal.

Embodiment [54] of the present disclosure relates to the method of embodiments [1] to [53], further comprising varying the linear velocity of the fibrous structure based on the surface defect signal.

Embodiment [55] of the present disclosure relates to the method of embodiments [1] to [54], further comprising varying a sampling rate at which at least one cross-sectional diameter is measured based on the surface defect signal.

Embodiment [56] of the present disclosure relates to the method of embodiments [1] to [55], further comprising classifying defects contained in the fibrous structure based on at least one surface defect signal.

Example [57] of the present disclosure relates to a fibrous structure obtained by the method of examples [1] to [57 ].

Embodiment [58] of the present disclosure relates to a fiber-containing structure obtained by the method of embodiments [1] to [56], wherein the fiber-containing structure is a wire or braid.

Embodiment [59] of the present disclosure relates to a fiber-containing structure obtained by the method of embodiments [1] to [56], wherein the fiber-containing structure is a yarn having a twist of less than 10 turns/meter.

Embodiment [60] of the present disclosure relates to the defect-detecting fiber-containing structure obtained by the method of embodiments [1] to [56], wherein the defect-detecting fiber-containing structure is a core-sheath structure having a braided or laid sheath.

An embodiment [61] of the present disclosure relates to an apparatus comprising: (A) An extrusion apparatus configured to form a fibrous structure, a braiding machine configured to form a fibrous structure, a tensioning assembly configured to apply tension to the fibrous structure, a finish applicator configured to apply a coating to the fibrous structure, a godet assembly configured to stretch the fibrous structure, a winding assembly configured to wind the fibrous structure onto a spool, or a combination thereof; (B) A defect detector configured to measure at least one cross-sectional diameter of the fibrous structure by: transmitting light onto the fiber-containing structure with a projector, detecting a profile image of the fiber-containing structure with a light receiver, and calculating a cross-sectional diameter based on a decrease in an amount of light detected by the light receiver relative to a total amount of light transmitted by the projector; and (C) a processor configured to compare the at least one diameter signal, optionally the at least one signal processed diameter signal, or a combination thereof, obtained from the defect detector to at least one reference signal to obtain at least one surface defect signal of the surface defect output versus the length of the fibrous structure, wherein the defect detector measures the at least one cross-sectional diameter as the fibrous structure passes linearly through the defect detector.

Embodiment [62] of the present disclosure relates to the apparatus of embodiment [61] wherein the fibrous structure is passed linearly through the at least one defect detector at a linear velocity of at least 300 meters per minute.

Embodiment [63] of the present disclosure relates to the apparatus of embodiments [61] and [62], wherein the fibrous structure is a woven fibrous structure or a skein fibrous structure and the fibrous structure passes linearly through the at least one detector at a linear velocity of at least 1 meter/min.

Embodiment [64] of the present disclosure relates to the apparatus of embodiments [61] to [63], wherein the fiber-containing structure is a nonwoven fiber-containing structure having a twist of less than 1 revolution per meter, the fiber-containing structure is a woven fiber-containing structure, or the fiber-containing structure is a skein fiber-containing structure.

Embodiment [65] of the present disclosure is directed to the apparatus of embodiments [61] to [64], wherein the fiber-containing structure is a core-sheath structure comprising a core and a braided sheath of strands surrounding the core.

Embodiment [66] of the present disclosure is directed to the apparatus of embodiments [61] to [65], wherein the fiber-containing structure is a cord having a core-sheath structure comprising a braided sheath surrounding the core, and the braiding angle of the braided sheath in a relaxed state ranges from about 5 ° to about 85 °.

Embodiment [67] of the present disclosure is directed to the apparatus of embodiments [61] to [66], wherein the fiber-containing structure is a cord having a core-sheath structure including a braided sheath surrounding the core, and the braided sheath has a weft count of 6 to 3000 filament unit crossings per meter in a relaxed state.

Embodiment [68] of the present disclosure relates to the apparatus of embodiments [61] to [67], wherein the fiber-containing structure is a cord having a core-sheath structure including a braided sheath surrounding the core, and the number of strands (ends) of the braided sheath is 3 to 24 ends.

Embodiment [69] of the present disclosure is directed to the apparatus of embodiments [61] to [68] wherein the fiber-containing structure is a cord having a skein structure comprising a nonwoven sheath surrounding a core.

Embodiment [70] of the disclosure relates to the apparatus of embodiments [61] to [69], wherein the fiber-containing structure comprises organic fibers.

Embodiment [71] of the present disclosure relates to the apparatus of embodiments [61] to [70], wherein the fiber-containing structure comprises synthetic fibers having a tensile strength greater than 12 cN/dtex.

Embodiment [72] of the present disclosure relates to the apparatus of embodiments [61] to [71], wherein the fiber-containing structure comprises at least one selected from the group consisting of: liquid crystalline polyester filaments, aramid filaments, copolyaramid filaments, polyetheretherketone filaments, poly (p-phenylene benzobisoxazole) filaments, ultra-high molecular weight polyethylene filaments, high modulus polyethylene filaments, polypropylene filaments, polyethylene terephthalate filaments, polyamide filaments, poly hydroquinone diimidazole pyridine filaments, and high strength polyvinyl alcohol filaments.

Embodiment [73] of the present disclosure is directed to the apparatus of embodiments [61] to [72], wherein the fiber-containing structure comprises synthetic fibers and at least one of a lubricant, staple fibers, and a surface coating.

Embodiment [74] of the present disclosure is directed to the apparatus of embodiments [61] to [73], wherein the fiber containing structure is a cord having a linear density of about 30 to about 10000 denier.

Embodiment [75] of the present disclosure is directed to the apparatus of embodiments [61] to [74], wherein the fibrous structure has a maximum cross-sectional diameter ranging from about 20 μm to about 10mm.

Embodiment [76] of the present disclosure relates to the apparatus of embodiments [61] to [75], wherein the fibrous structure has an average cross-sectional diameter ranging from about 20 μm to about 10mm.

Embodiment [77] of the present disclosure relates to the apparatus of embodiments [61] to [76], wherein the at least one defect detector is in series with the extrusion apparatus.

An embodiment [78] of the invention relates to the apparatus of embodiments [61] to [77], wherein the at least one defect detector is in series with the knitting machine.

An embodiment [79] of the invention is directed to the apparatus of embodiments [61] to [78], comprising a defect detector array in series with the braiding machine such that the fiber-containing structure passes linearly through the defect detector array, wherein: the defect detector array includes at least two defect detectors in series; rotating the at least two defect detectors relative to each other by a detector offset angle such that different contour images of the fibrous structure are detected by the at least two defect detectors; and detector offset angles range from 1 deg. to less than 360 deg..

An embodiment [80] of the present disclosure relates to the apparatus of embodiment [79] wherein the defect detector array comprises at least three defect detectors in series.

Embodiment [81] of the present disclosure is directed to the apparatus of embodiments [79] and [80] wherein the separation distance between at least two defect detectors in the array of defect detectors ranges from 1mm to 100mm.

Embodiment [82] of the present disclosure relates to the apparatus of embodiments [79] to [81], wherein: the defect detector comprises two projectors for transmitting light onto the fibrous structure and two light receivers for detecting a profile image of the fibrous structure; the two projectors comprise a projector a for transmitting light a onto a surface a of the fibrous structure and a projector B for transmitting light B onto a surface B of the fibrous structure; the two light receivers comprise a light receiver A for detecting a contour image A containing the fiber structure and a light receiver B for detecting a contour image B containing the fiber structure; projector a is optically aligned with light receiver a and projector B is optically aligned with light receiver B; projector a and projector B rotate a projector offset angle relative to each other, and light receiver a and light receiver B rotate a light receiver offset angle relative to each other; and projector offset angles and optical receiver offset angles range from 5 ° to 175 °.

Embodiment [83] of the disclosure relates to the apparatus of embodiments [61] to [82], wherein the at least one defect detector is in series with the tensioning assembly.

Embodiment [84] of the present disclosure relates to the apparatus of embodiments [61] to [83], wherein the at least one defect detector is in series with the finish applicator.

Embodiment [85] of the disclosure is directed to the apparatus of embodiments [61] to [84], wherein at least one defect detector is in series with the godet assembly.

Embodiment [86] of the present disclosure is directed to the apparatus of embodiments [61] to [85], wherein at least one defect detector is in series with the winding assembly.

Embodiment [87] of the present disclosure is directed to the apparatus of embodiments [61] to [86], wherein at least one defect detector is in series with at least one roller.

An embodiment [88] of the present disclosure is directed to the apparatus of embodiments [61] - [87] wherein at least two defect detectors are adjacently connected in series together as an array of defect detectors, and the detector offset angle between adjacently positioned defect detectors in the array of defect detectors ranges from 1 ° to less than 360 °.

Embodiment [89] of the present disclosure is directed to the apparatus of embodiments [61] to [88] wherein at least three defect detectors are adjacently connected in series together as an array of defect detectors, and the detector offset angle between adjacently positioned defect detectors in the array of defect detectors ranges from 1 ° to less than 360 °.

An embodiment [90] of the present disclosure is directed to the apparatus of embodiments [61] to [89], wherein the defect detector is a multi-axis defect detector configured to measure at least two cross-sectional diameters of the fiber-containing structure such that an offset angle between the at least two cross-sectional diameters ranges from 5 ° to 175 °.

Embodiment [91] of the present disclosure relates to the apparatus of embodiments [61] - [90], wherein: the defect detector comprises two projectors for transmitting light onto the fibrous structure and two light receivers for detecting a profile image of the fibrous structure; the two projectors comprise a projector a for transmitting light a onto a surface a of the fibrous structure and a projector B for transmitting light B onto a surface B of the fibrous structure; the two light receivers comprise a light receiver A for detecting a contour image A containing the fiber structure and a light receiver B for detecting a contour image B containing the fiber structure; projector a is optically aligned with light receiver a and projector B is optically aligned with light receiver B; projector a and projector B rotate a projector offset angle relative to each other, and light receiver a and light receiver B rotate a light receiver offset angle relative to each other; and projector offset angles and optical receiver offset angles range from 5 ° to 175 °.

Embodiment [92] of the present disclosure relates to the apparatus of embodiments [61] to [91], wherein the projector comprises a laser diode or a light emitting diode.

An embodiment [93] of the disclosure relates to the device of embodiments [61] to [92], wherein the light receiver is an active pixel sensor.

An embodiment [94] of the present disclosure relates to the apparatus of embodiments [61] to [93] wherein the light receiver is an active pixel sensor comprising a photodiode image sensor, a Charge Coupled Device (CCD) image sensor, or a Complementary Metal Oxide Semiconductor (CMOS) image sensor.

An embodiment [95] of the present disclosure relates to the apparatus of embodiments [61] to [94], further comprising (D) an imaging detector configured to image the surface of the fiber-containing structure, wherein the imaging detector images the surface by illuminating the fiber-containing structure with imaging light and receiving a reflected image of the surface with an imaging receiver.

Embodiment [96] of the present disclosure relates to the apparatus of embodiments [61] to [95], further comprising (D) an imaging detector configured to image a surface of the fibrous structure, wherein: an imaging detector images the surface by illuminating the fiber-containing structure with imaging light and receiving a reflected image of the surface with an imaging receiver; and at least one imaging detector is in series with the extrusion apparatus, the braiding machine, the tensioning assembly, the finish applicator, the godet assembly, the winding assembly, or a combination thereof.

Embodiment [97] of the disclosure relates to the apparatus of embodiments [61] to [96] that does not include imaging the surface of the fibrous structure with an imaging detector that receives the reflected image of the surface.

Embodiment [98] of the present disclosure is directed to the apparatus of embodiments [61] to [97] wherein the defect detector measures at least one cross-sectional diameter at a sampling rate of at least 5000 samples per second.

Embodiment [99] of the present disclosure relates to the apparatus of embodiments [61] - [98], wherein: at least one cross-sectional diameter measurement is performed at a sampling rate; adjusting the sampling rate of the at least one defect detector such that measurements are taken at constant intervals along the length of the fibrous structure; and the constant spacing ranges from 10nm to 1cm.

An embodiment [100] of the present disclosure relates to the apparatus of embodiments [61] to [99], wherein the at least one surface defect signal comprises an amplitude surface defect count signal of amplitude surface defect count versus fiber-containing structure length, wherein: generating an amplitude surface defect count signal by comparing the diameter signal with a reference signal for the length of the fibrous structure having a maximum cross-sectional diameter; when the amplitude of the diameter signal is less than or equal to the maximum cross-sectional diameter at a particular point along the length of the fiber-containing structure, the amplitude surface defect count is zero; and when the amplitude of the diameter signal is greater than the maximum cross-sectional diameter at a particular point along the length of the fiber-containing structure, the amplitude surface defect count is greater than zero, such that the amplitude surface defect count greater than zero is a positive integer corresponding to the amplitude of the diameter signal being greater than a percentage of the maximum cross-sectional diameter.

An embodiment [101] of the present disclosure is directed to the apparatus of embodiments [61] to [100], wherein the at least one surface defect signal comprises a slope surface defect count versus slope surface defect count signal comprising a fiber structure length, wherein: generating a slope surface defect count signal by comparing the signal-processed diameter signal with a reference signal containing a maximum first derivative of the fiber structure length of the diameter signal, wherein the signal-processed diameter signal is obtained by signal processing the diameter signal to obtain the first derivative of the diameter signal; the slope surface defect count is zero when the absolute value of the first derivative of the diameter signal is less than or equal to the maximum first derivative of the diameter signal at a particular point along the length of the fibrous structure; and when the absolute value of the first derivative of the diameter signal is greater than the largest first derivative of the diameter signal at a particular point along the length of the fibrous structure, the slope surface defect count is greater than zero such that the slope surface defect count greater than zero is a positive integer corresponding to the absolute value of the first derivative of the diameter signal being greater than a percentage of the largest first derivative of the diameter signal.

Embodiment [102] of the present disclosure relates to the apparatus of embodiments [61] to [101], wherein the at least one surface defect signal comprises a curvature surface defect count versus a curvature surface defect count signal comprising a fiber structure length, wherein: generating a curvature surface defect count signal by comparing the signal-processed diameter signal with a reference signal comprising a maximum second derivative of the fiber structure length of the diameter signal, wherein the signal-processed diameter signal is obtained by signal processing the diameter signal to obtain a second derivative of the diameter signal; when the absolute value of the second derivative of the diameter signal is less than or equal to the maximum second derivative of the diameter signal at a particular point along the length of the fibrous structure, the curvature surface defect count is zero; and when the absolute value of the second derivative of the diameter signal is greater than the maximum second derivative of the diameter signal at a particular point along the length of the fibrous structure, the curvature surface defect count is greater than zero such that the curvature surface defect count greater than zero is a positive integer corresponding to the absolute value of the second derivative of the diameter signal being greater than a percentage of the maximum second derivative of the diameter signal.

Embodiment [103] of the present disclosure relates to the apparatus of embodiments [61] - [102], wherein the reference signal is a constant reference signal that is constant along the length of the fibrous structure.

Embodiment [104] of the present disclosure relates to the apparatus of embodiments [61] to [103], wherein the reference signal is a variable reference signal that varies at one or more points along the length of the fibrous structure.

An embodiment [105] of the present disclosure relates to the apparatus of embodiments [61] to [104], further comprising a speedometer configured to measure the linear velocity of the fibrous structure.

The previous description is provided to enable any person skilled in the art to make or use the present invention, and is provided in the context of a particular application and its requirements. Various modifications to the embodiments disclosed herein will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. In this regard, in a broad sense, certain embodiments of the disclosure may not exhibit every benefit of the present invention.

Claims

1. A method, comprising:

passing the fibrous structure linearly through at least one defect detector;

measuring at least one cross-sectional diameter of the fibrous structure with a defect detector to obtain at least one diameter signal of diameter versus length of the fibrous structure;

optionally, signal processing the diameter signal to obtain at least one signal processed diameter signal; and

comparing the diameter signal, the signal processed diameter signal, or a combination thereof to at least one reference signal to produce at least one surface defect signal of the surface defect output versus the length of the fibrous structure,

wherein:

the defect detector measures the cross-sectional diameter of the fibrous structure by: transmitting light onto the fiber-containing structure with a projector, detecting a profile image of the fiber-containing structure with a light receiver, and calculating a cross-sectional diameter based on a decrease in an amount of light detected by the light receiver relative to a total amount of light transmitted by the projector; and is also provided with

At least one defect detector is in series with an extrusion apparatus configured to form the fibrous structure, a braiding machine configured to form the fibrous structure, a tensioning assembly configured to apply tension to the fibrous structure, a finish applicator configured to apply a coating to the fibrous structure, a godet assembly configured to stretch the fibrous structure, a winding assembly configured to wind the fibrous structure onto a spool, or a combination thereof.

2. The method of claim 1, further comprising:

the fibrous structure is formed by an extrusion process wherein at least one defect detector is in series with the extrusion apparatus.

3. The method of claim 1, further comprising:

the fiber-containing structure is formed by a braiding process, wherein at least one defect detector is in series with the braiding machine.

4. A method according to claim 3, further comprising:

forming a fibrous structure by a braiding process, wherein:

the defect detector array is connected in series with the braiding machine so that the fiber-containing structure linearly passes through the defect detector array; the defect detector array includes at least two defect detectors in series;

the at least two defect detectors are rotated relative to each other by a detector offset angle such that different contour images of the fibrous structure are detected by the at least two defect detectors; and is also provided with

The detector offset angle ranges from 1 deg. to less than 360 deg..

5. The method of claim 4, wherein the defect detector array comprises at least three defect detectors in series.

6. The method of any one of claims 1-5, wherein:

the defect detector comprises two projectors for transmitting light onto the fibrous structure and two light receivers for detecting a profile image of the fibrous structure;

The two projectors comprise a projector a for transmitting light a onto a surface a of the fibrous structure and a projector B for transmitting light B onto a surface B of the fibrous structure;

the two light receivers comprise a light receiver A for detecting a contour image A containing the fiber structure and a light receiver B for detecting a contour image B containing the fiber structure;

projector a is optically aligned with light receiver a and projector B is optically aligned with light receiver B;

projector a and projector B rotate a projector offset angle relative to each other, and light receiver a and light receiver B rotate a light receiver offset angle relative to each other; and is also provided with

The projector offset angle and the optical receiver offset angle range from 5 ° to 175 °.

7. The method of any of claims 1-6, wherein the defect detector is a multi-axis defect detector configured to measure at least two cross-sectional diameters of the fiber-containing structure such that an offset angle between the at least two cross-sectional diameters ranges from 5 ° to 175 °.

8. The method of any of claims 1-7, further comprising:

imaging the surface of the fibrous structure with at least one imaging detector,

wherein:

an imaging detector images the surface by illuminating the fiber-containing structure with imaging light and receiving a reflected image of the surface with an imaging receiver; and is also provided with

At least one imaging detector is in series with the extrusion apparatus, braiding machine, tensioning assembly, finish applicator, godet assembly, winding assembly, or combinations thereof.

9. The method of any of claims 1-8, wherein the at least one surface defect signal comprises an amplitude surface defect count signal of amplitude surface defect count versus fiber-containing structure length, wherein:

generating an amplitude surface defect count signal by comparing the diameter signal with a reference signal for the length of the fibrous structure having a maximum cross-sectional diameter;

when the amplitude of the diameter signal is less than or equal to the maximum cross-sectional diameter at a particular point along the length of the fiber-containing structure, the amplitude surface defect count is zero; and is also provided with

When the amplitude of the diameter signal is greater than the maximum cross-sectional diameter at a particular point along the length of the fiber-containing structure, the amplitude surface defect count is greater than zero, such that the amplitude surface defect count greater than zero is a positive integer corresponding to the amplitude of the diameter signal being greater than a percentage of the maximum cross-sectional diameter.

10. The method of any of claims 1-8, wherein the at least one surface defect signal comprises a slope surface defect count signal of slope surface defect count versus fiber-containing structure length, wherein:

Generating a slope surface defect count signal by comparing the signal-processed diameter signal with a reference signal containing a maximum first derivative of the fiber structure length of the diameter signal, wherein the signal-processed diameter signal is obtained by signal processing the diameter signal to obtain the first derivative of the diameter signal;

the slope surface defect count is zero when the absolute value of the first derivative of the diameter signal is less than or equal to the maximum first derivative of the diameter signal at a particular point along the length of the fibrous structure; and is also provided with

When the absolute value of the first derivative of the diameter signal is greater than the largest first derivative of the diameter signal at a particular point along the length of the fiber-containing structure, the slope surface defect count is greater than zero such that the slope surface defect count greater than zero is a positive integer corresponding to the absolute value of the first derivative of the diameter signal being greater than a percentage of the largest first derivative of the diameter signal.

11. The method of any of claims 1-8, wherein the at least one surface defect signal comprises a curvature surface defect count versus a curvature surface defect count signal for a length of the fibrous structure, wherein:

generating a curvature surface defect count signal by comparing the signal-processed diameter signal with a reference signal comprising a maximum second derivative of the fiber structure length of the diameter signal, wherein the signal-processed diameter signal is obtained by signal processing the diameter signal to obtain a second derivative of the diameter signal;

When the absolute value of the second derivative of the diameter signal is less than or equal to the maximum second derivative of the diameter signal at a particular point along the length of the fibrous structure, the curvature surface defect count is zero; and is also provided with

When the absolute value of the second derivative of the diameter signal is greater than the maximum second derivative of the diameter signal at a particular point along the length of the fiber-containing structure, the curvature surface defect count is greater than zero, such that the curvature surface defect count greater than zero is a positive integer corresponding to the absolute value of the second derivative of the diameter signal being greater than a percentage of the maximum second derivative of the diameter signal.

12. The method of any of claims 1-11, further comprising:

the linear velocity of the fibrous structure is measured using at least one speedometer.

13. The method of any of claims 1-11, further comprising:

based on the surface defect signal, modifying operation of the extrusion apparatus, braiding machine, tensioning assembly, finish applicator, godet assembly, winding assembly, or a combination thereof.

14. An apparatus, comprising:

(A) An extrusion apparatus configured to form a fibrous structure, a braiding machine configured to form a fibrous structure, a tensioning assembly configured to apply tension to the fibrous structure, a finish applicator configured to apply a coating to the fibrous structure, a godet assembly configured to stretch the fibrous structure, a winding assembly configured to wind the fibrous structure onto a spool, or a combination thereof;

(B) A defect detector configured to measure at least one cross-sectional diameter of the fibrous structure by: transmitting light onto the fiber-containing structure with a projector, detecting a profile image of the fiber-containing structure with a light receiver, and calculating a cross-sectional diameter based on a decrease in an amount of light detected by the light receiver relative to a total amount of light transmitted by the projector; and

(C) A processor configured to compare the at least one diameter signal, optionally the at least one signal processed diameter signal, or a combination thereof, obtained from the defect detector to at least one reference signal to obtain at least one surface defect signal of the surface defect output versus the length of the fibrous structure, wherein the defect detector measures the at least one cross-sectional diameter as the fibrous structure passes linearly through the defect detector.

15. The apparatus of claim 14, wherein at least one defect detector is in series with the extrusion apparatus.

16. The apparatus of claim 14, wherein the at least one defect detector is in series with the knitting machine.

17. The apparatus of claim 16, comprising a defect detector array in series with the braiding machine such that the fiber-containing structure passes linearly through the defect detector array, wherein:

The defect detector array includes at least two defect detectors in series;

The detector offset angle ranges from 1 deg. to less than 360 deg..

18. The apparatus of any of claims 14-17, wherein the defect detector array comprises at least three defect detectors in series.

19. The apparatus of any of claims 14-18, wherein:

Projector a and projector B rotate a projector offset angle relative to each other, and light receiver a and light receiver B rotate a light receiver offset angle relative to each other;

20. The apparatus of any of claims 14-19, wherein at least one defect detector is in series with the tensioning assembly or finish applicator or godet assembly or winding assembly or at least one roller or any combination thereof.

21. The apparatus of any of claims 14-20, further comprising:

a speedometer configured to measure a linear velocity of the fibrous structure.