EP2868791A1 - Thread take-up in a device for treating synthetic thread - Google Patents

Abstract

The subject of the invention is a son treatment device comprising a heat-setting chamber, closed at each of its ends by a sealing head each comprising two rollers, a conveyor belt, on which the threads are deposited, in bulk or in loops, in the form of a sheet and circulate in the heat-setting enclosure, a thread recovery device, for pulling the son of the conveyor belt after heat setting. This device is characterized in that it comprises, in addition, a fixed wire cooling unit (7) acting downstream of the heat-setting, and in that the recovery device removes the wire from the conveyor belt at the level of a recovery zone which is normally located in the cooling unit (7). The invention may also relate to a cooling unit and a detection means.

Description

The present invention relates to the field of synthetic wire processing, in particular that of equipment used in the complete lines of shaping of synthetic thread.

In this type of equipment, the son are generally deposited in a sheet on a conveyor belt which brings them into a heat-setting chamber in which they undergo a heat treatment having the effect of setting their shape, thanks to steam.

The son laid in a web on the conveyor belt can come directly from the feed coils, and then be deposited in the form of turns. Alternatively, upstream of this heat-setting chamber, the synthetic thread can pass through a crimping step in a curling box. The wires are then deposited in bulk on the conveyor belt. Such a curling box conventionally comprises a pair of counter-rotating rollers, which bring its curl to the thread.

A cooling unit is conventionally mounted downstream of the heat-setting enclosure. The yarns are finally removed from the conveyor belt as a strand by a thread take-up device, and then stored on the reels of a rack.

The thread take-up device generally operates by pulling the threads up, thereby separating them from the conveyor belt, and it is particularly important to control where the threads are separated from the conveyor belt. The recovery zone, that is to say the place where the wires deviate from the conveyor belt and separate from the sheet, must thus be constantly monitored and be in a specific location of the line, or window of recovery, delimited, on the side of the heat-setting enclosure, by a lower limit, and, on the opposite side, by an upper limit.

The separation of the wires having the effect of decomposing the sheet, optical solutions have been developed to accurately detect the edge of the sheet, and thus monitor the exact location of the recovery zone. Current solutions are based on photodiodes, and measure the amount of light that can pass through the conveyor belt into the recovery window. If a large amount of light can pass through the recovery window, this means that the recovery zone is close to the lower limit and therefore the recovery is too fast since the wires are not quite accumulated and the tablecloth is short. If a small amount of light can pass through the recovery window, this means that the recovery zone is close to the upper limit and recovery is not fast enough since the wires form a very long layer. The regulation of the recovery speed, which impacts the position of the recovery zone in the recovery window, is therefore based on this amount of light.

Nevertheless, in some cases, the edge of the web may not be clear, especially given the texture given before the son, and this detection can then be made more difficult. The consequent regulation is thus made less reliable and precise. Another source of difficulties is an irregular arrangement of the threads in the heart of the web, which can lead to holes and clusters of threads, making the measurement of an optical intensity difficult to represent the state of the web. In addition, the fact that the wires are normally free on the conveyor belt makes the control more delicate. Finally, the ambient brightness may also have an impact on the amount of light received by the detection cell.

The invention aims essentially to improve the recovery of wire, and in particular to better detect the location of the recovery zone. For this purpose, the invention proposes in particular to have the recovery zone in the fixed cooling unit, where a circulation of air can often keep the son against the carpet, whether in the form of a sheet or strand, or to modify the principle of detection of the zone of recovery and to analyze rather the geometry.

For this purpose, the subject of the invention is a wire treatment device comprising a heat-setting enclosure, possibly closed at each of its ends by a sealing head each comprising two rollers, a conveyor belt, on which the wires are deposited. , in bulk or in loops, in the form of a sheet and circulate in the heat-setting chamber, and a thread recovery device, for pulling the son of the conveyor belt after heat-fixing.

This device is characterized in that it further comprises a fixed wire cooling unit acting downstream of the heat-setting, and in that the recovery device removes the conveyor belt wire at a zone recovery that is normally found in the cooling unit.

Another subject of the invention is a wire cooling unit, for a wire treatment device comprising a heat-setting chamber, possibly closed at each of its ends by a sealing head each comprising two rollers, a conveyor belt, on which the son are deposited, in bulk or in loops, in the form of a sheet and circulate in the heat-setting enclosure, as well as a thread take-up device, for pulling the conveyor belt threads after heat setting at a recovery zone which is normally in the cooling unit, said wire cooling unit being intended for fixed mounting downstream of the heat setting.

This cooling unit is characterized in that it has a detection means for detecting the end of the sheet of yarns from which the recovery device pulls the threads, and thus check the presence of the recovery zone within of the recovery window.

Another subject of the invention is a detection means, for a son treatment device comprising a heat-setting enclosure, possibly closed at each of its ends by a sealing head each comprising two rollers, a conveyor belt, on which the son are deposited, in bulk or in loops, in the form of a sheet and circulate in the heat-setting enclosure, and a thread take-up device, for pulling the threads of the conveyor belt after heat-fixing, said detection means for detecting the end of the thread sheet from which the take-up device pulls the threads, and thus to check the presence of the pick-up area within the pickup window.

This detection means is characterized in that it analyzes the geometry of the sheet in the recovery window.

• la figure 1 montre une ligne de traitement complète ;
• la figure 2 illustre une unité de refroidissement comprenant un moyen de détection de la zone de reprise, et
• la figure 3 illustre une réalisation particulière du moyen de détection de zone de reprise.

Other aspects of the invention will appear in the following description, which relates to a preferred embodiment, given by way of non-limiting example, and explained with reference to the appended diagrammatic drawings, in which:

• the figure 1 shows a complete treatment line;
• the figure 2 illustrates a cooling unit comprising means for detecting the area of recovery, and
• the figure 3 illustrates a particular embodiment of the recovery zone detection means.

The treatment line illustrated in figure 1 thus shows a complete wire processing device 1, comprising a heat-setting enclosure 3, possibly closed at each of its ends by a sealing head 4 each comprising two rollers, a conveyor belt 5, on which the threads are deposited, in bulk or in loops, in the form of a sheet and circulate in the heat-setting chamber 3, and a device 6 thread recovery, for pulling the threads of the conveyor belt 5 after heat-setting, in particular for pulling them in the form of strand. As will be described later, the carpet 5 is preferably such that air can flow through it, or even light and has openings for this purpose.

The son undergo a heat treatment in the enclosure 3 heat-setting, thanks to the steam that circulates there. The enclosure 3 may be in the form of an elongate body open at its ends, or have roll seal heads.

The processing device 1 also comprises an upstream wire feeding rack which are then in the form of coils. In the case illustrated in figure 1 the yarns then pass through a curling box 2 which forms a texturing means 2. The yarns are pressed into this curling box 2 by means of two counter-rotating rollers, or also by means of an inlet roll disposed upstream of said rollers of crimp parallel to them and against which circulate said son before passing between the rollers. This texturing means 2 is not essential, and other means of texturing, or even microtexturation may be provided in addition or alternatively.

In particular embodiments, the processing device 1 thus comprises a wire texturing means 2, upstream of the heat-setting chamber 3 and in the form of a curling box which comprises a pair of counter-rotating crimping rollers.

The yarns are then deposited in a sheet on a conveyor belt to circulate in the heat-setting chamber 3, the latter being sealed at its ends by each time a sealing head 4, having two counter-rotating rollers, between which circulates said carpet 5.

After treatment, the son are released in the form of strands of the carpet 5 by simple traction performed by the recovery device 6. After passing through the recovery device 6, the son are stored on reels, after a possible passage through an accumulator .

The processing device 1 further comprises a fixed wire cooling unit 7 acting downstream of the heat-setting, thanks to a flow of air. Preferably, the cooling unit 7 comprises an air ventilation which has the effect of pressing the son, in a sheet or strand, against the conveyor belt. For this purpose, the cooling unit 7 comprises a hollow box 8 above which circulates the conveyor belt 5, the ventilation having the effect of extracting air. This cooling unit 7 is therefore intended for fixed mounting downstream of the heat-setting.

During transportation on the carpet 5, the son are arranged in a sheet, resting on the surface of the carpet 5. The recovery device 6 pulls the son present on the surface of the carpet 5, from a point offset from the plane in which the carpet travels. 5. Thus, the son, in the form of strand, moves away from the belt 5 towards this point of traction of the recovery device 6, leaving the surface of the belt 5 at a location of the treatment device 1, here named zone of recovery. Since the yarn, when pulled by the recovery device 6, is still in the form of a sheet occupying a certain width on the carpet 5, the recovery zone also extends over part of the width of the carpet 5 , especially over the entire width of the carpet 5. This recovery zone materializes the front of the web from which the son are removed in the form of strand.

A good execution of the treatment process requires that the recovery zone, and therefore the place where the threads move away from the web and offset from the plane of the belt 5, is between two fixed limits with respect to the processing device 1. A first limit is upstream of the wire processing steps, namely towards the heat-setting chamber 3, and a second is downstream of the wire processing steps. The recovery device 6 pulls the yarns from the web at its own speed, and the web advances, meanwhile, thanks to the belt 5 which can have a speed independent of that caused by the recovery device 6.

An exact synchronization between the recovery device 6 and the advance of the sheet is delicate, and it is therefore proposed to ensure that the front of the sheet, that is to say the area of recovery, remains well between them. two predefined limits.

If the area of recovery approaches the limit upstream of the process, the rate of recovery is excessive compared to the displacement of the web. It is therefore necessary to slow down the recovery to prevent the recovery device from absorbing too much upstream wire in the process.

If the recovery zone approaches the limit downstream of the process, the recovery rate is not sufficient compared to the movement of the web. It is then necessary to accelerate the recovery to prevent the sheet reaches an excessive volume relative to the space that is devolved thereon on the processing device 1.

Thus, the position of the recovery zone between these two limits, as well as its evolution between them during the process, makes it possible to regulate the speed of recovery, to ensure that the zone of recovery remains well between these two limits all at the same time. long operation. For this purpose, in advantageous embodiments, the thread take-up device 6 comprises a regulation means which takes into account the detected position of the sheet of threads, in particular in the cooling unit 7, to adjust the speed with which the recovery device 6 pulls the strand of the sheet.

It is therefore useful for the processing device 1 to be provided with means for detecting the position of the thread recovery zone between fixed marks. Preferably, the detection means analyzes the geometry of the web in the recovery window, between the lower limit and the upper limit, over the width of the belt 5.

The son being however positioned on the belt 5 in the form of a free web, its maintenance and therefore the position of the recovery zone can be difficult to ensure. It is therefore advantageous to provide a recovery zone at a stage of the process where the wires can be stabilized on the belt 5. It is thus preferable to provide a wire recovery zone in the cooling unit 7.

Indeed, in this unit, the belt 5, on which the son are then arranged in a sheet, circulates in a box 8 from which the air is sucked, so as to create a flow of air through the carpet 5 and around the wires, to cool them. This suction has the effect of exerting a force on the son of the sheet so that they are pressed against the surface of the belt 5 and are thus stabilized.

Thus, the recovery device 6 removes the conveyor belt thread at a recovery zone which is normally located in the cooling unit 7, the recovery window being thus in said unit, so that the window recovery is provided where the cooling unit 7 plates the wire against the conveyor belt 5.

As shown in figure 3 , the casing 8 has a lateral outlet at the level of which is mounted a ventilation propeller, which Extracts the air from the box 8. The conveyor belt 5 travels flat above the box 8 and thus forms the top wall. The other walls do not allow air circulation and it is through the carpet 5 that the air arrives in the box 8 to then be expelled by the side outlet. The belt 5 thus has sufficient perforations through which air can circulate, and it is between the suction unit and the sheet of son.

The box 8 is mounted on a frame having a horizontal base wall and four legs extending from said wall, the belt 5 flowing under this wall on its return to the upstream phases of the process.

By providing a recovery window at the fixed cooling unit 7, and thus reusing the latter to ensure the holding of the son sheet during the recovery, it thus avoids adding additional elements in the processing device 1 and it is also possible to avoid exerting excessive mechanical stresses on the threads, which could have effects on their shape or hinder the recovery. The suction of air through the conveyor belt 5 makes it possible to create a homogeneous force on the sheet of yarn and to hold it sufficiently, without requiring excessive forces for the recovery device 6.

In general, and therefore the recovery window is located in the cooling unit 7 as just described or it is located elsewhere during the course of the web on the conveyor belt, the device of 1 advantageously has a means of detecting the recovery zone, that is to say a means for detecting the edge of the web where the son are separated in strand, in order to provide a signal useful to a control loop that drives the recovery device 6, so that the recovery zone is in the predefined recovery window, between the two limits already mentioned.

In order to reliably detect the position of the recovery zone, and thus not to be hampered by local irregularities that may present the web, such as holes or accumulations, the detection means advantageously operates by an observation of the geometrical form that takes the son in the window of recovery, and analyzes this form to identify the front of the sheet, and thus the departure of the strands, that is to say to identify a recovery zone.

The detection means therefore identifies the contours of the sheet and a calculator performs the calculation necessary to identify the area of the sheet. recovery, since it is the area from which the sheet breaks down into strands, which can be observed visually. It thus geometrically detects the profile presented by all the son disposed on the carpet 5. For this purpose, in general, the detection means comprises, on the one hand, an illumination means 9, placed on one side of the conveyor belt 5, and on the other hand, an optical detection cell 10 placed on the other side of the conveyor belt, and preferably also a computer for implementing a method of geometric analysis of the web in the recovery window.

The detection means thus comprises a detection cell 10, which displays the wires as they are arranged on the carpet 5. In order to promote the optical detection of the contours of the pile of yarn on the carpet 5, it is preferable to associating illumination means 9 with the detection cell 10. The illumination means 9 therefore project light towards the detection cell 10, the conveyor belt being situated between the illumination means 9 and said detection cell 10. The conveyor belt 5 has openings which allow enough light to pass through so that it is essentially stopped only by the threads on the carpet 5.

The wires arranged in a sheet significantly obstruct the flow of light, while the son in the form of strand, distant from each other, more easily circulate light. The detection cell 10 can therefore differentiate the son in the form of a sheet, characterized by a very low light intensity, the son in the form of strands pulled by the recovery device 6, characterized by a higher light intensity. The full luminous power corresponds, of course, to a recovery window devoid of wires.

The detection cell 10 is normally able to observe the location of the wires on the conveyor belt between the two previously mentioned boundaries. In particular embodiments, the detection cell 10 comprises a camera. The detection cell 10 can thus take the form of a camera or a vision sensor, which sends a signal to a computer that analyzes the geometry identified to identify the area of recovery.

The illumination means 9 can also take different forms. Thus, in particular embodiments, the illumination means 9 takes the form of at least one elongate light source 11 extending substantially in the direction of travel of the conveyor belt. In other embodiments, the illumination means 9 takes the form of at least one elongated light source 11, extending substantially parallel to the conveyor belt, transversely to its direction of travel. More specifically, in some embodiments, the illumination means 9 takes the form of a pair of elongated light sources 11, each oriented towards the optical detection cell 10, arranged perpendicular to the direction of movement of the belt 5, in parallel on the carpet 5.

In general, the at least one light source 11 may take the form of a neon tube or a series of light-emitting diodes.

In embodiments not illustrated in the appended figures, the illumination means 9 comprises two elongated light sources 11 placed under the conveyor belt, one being disposed in the box 8, and the other outside. They are therefore separated by a wall of the box 8, and generally located where the mat 5 leaves the box 8, so that the maintenance exerted on the son during cooling is maximum. The detection means is therefore generally placed at the outlet of the box 8, and the detection cell 10 is thus above the belt, at the level of the zone from which it leaves the box 8.

In particular embodiments, the illuminating means 9 takes the form of a slab, extending substantially parallel to the conveyor belt. Such a light slab extends both in the direction of movement of the belt 5 and perpendicular to it.

In general, the illumination means 9 is therefore capable of sending enough light power through the entire recovery window to allow detection by the detection cell 10 in the case where the wire does not obstruct the circulation. .

The illumination means 9 is therefore positioned on one side of the sheet of yarn, and therefore of the mat 5, and the detection cell 10 is positioned on the other side.

In special cases where the recovery zone detection means is mounted in the cooling unit 7, and therefore the recovery window is positioned where suction ventilation plates the wires against the carpet 5 carrier, the illumination means 9 is placed in the box 8, the detection cell 10 being placed outside the box 8, vis-à-vis. In these cases, the cooling unit 7 has a detection means for detecting the end of the sheet of son from which the recovery device 6 pulls the son, and thus check the presence of the recovery zone within of the recovery window.

In the embodiment illustrated in figure 3 , the illumination means 9 is located in the box 8, under the carpet 5, the latter flowing in the upper part of said box 8. In general, the detection means is placed at least partly in the box 8. In this figure, the illumination means 9 takes the form of two elongate light sources 11, positioned to extend perpendicular to the axis of movement of the mat 5. Each of them is mounted adjustable on a cantilevered support in the box 8. This support has for this purpose two parallel grooves through which the light source can be slidably adjusted. The two light sources can thus be brought closer to or distant from one another, or else adjusted to ensure alignment with the detection cell 10. The distance of the light sources makes it possible to adjust the length of the light source. observation on the conveyor belt 5.

In the figure 3 an angle of approximately 45 °, for example, separates the axes connecting each light source 11 to the detection cell 10.

Each light source 11 advantageously has a set of baffles which prevents too wide a scattering of the light and each light source is oriented towards the detection cell 10. The use of two light sources rather than just one allows to homogenize the luminous intensity along the recovery window, and thus to improve the quality of the detection of the edge of the lap or zone of recovery, at any point in the recovery window.

The detection cell 10 is, for its part, disposed above the conveyor belt, and at a distance such that it can monitor the entire recovery window 6, between the two limits, one upstream of the process. the other downstream, and over the entire width that can take the sheet, ideally over the entire width of the carpet 5. The detection cell 10 is thus preferably on a support structure whose distance relative to the mat 5 is adjustable.

In the illustrated realization figure 2 , this support structure is in the form of two arches each placed against one side of the box 8, and fixed to it by means of lugs provided with screws provided for slide in an elongated groove provided on each of the two posts of the arch. The detection cell 10 extends from the central part of the arch to the central part of the other arch, perpendicular to the direction of movement of the carpet 5. As shown in FIG. figure 2 the detection cell 10 is preferably mounted between two lateral extensions each extending from one of the two central portions.

The possibility of adjusting the position of the light sources and the detection cell 10 along the axis of movement of the belt 5, the distance of the detection cell 10 from the carpet 5, the angle light sources, ensures a light projection over the entire recovery window and the entire width of the carpet 5, thus promoting detection of the recovery zone.

Of course, the invention is not limited to the embodiment described and shown in the accompanying drawings. Modifications are possible, in particular from the point of view of the constitution of the various elements, by different combination of all or part of the characteristics described above, or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims (15)

Device for treating (1) wires comprising a heat-setting enclosure (3), optionally closed at each of its ends by a sealing head (4) each comprising two rollers, a conveyor belt (5), on which the wires are deposited in bulk or in loops, in the form of a sheet and circulate in the enclosure (3) of heat-setting, and a device for taking up (6) wire to pull the threads of the conveyor belt (5) after heat setting,
characterized in that
the wire processing device (1) further comprises a fixed wire cooling unit (7) acting downstream of the heat setting, and in that
the recovery device (6) removes the conveyor belt (5) conveyor at a recovery zone which is normally located in the cooling unit (7). Wire treatment device (1) according to claim 1, characterized in that
the cooling unit (7) comprises an air ventilation which has the effect of pressing the son, in sheets or in strand, against the conveyor belt (5), and the recovery window is provided where the unit of cooling (7) plates the wire against the conveyor belt (5). Wire treatment device (1) according to one of Claims 1 to 2, characterized in that
the cooling unit (7) comprises a hollow box (8) above which the conveyor belt (5) circulates, the ventilation having the effect of extracting air therefrom. Wire treatment device (1) according to one of Claims 1 to 3, characterized in that
the cooling unit (7) has a detecting means for detecting the end of the sheet of yarns from which the take-up device (6) pulls the yarns, and thus check the presence of the recovery zone within of the recovery window. Wire treatment device (1) according to claim 3 and according to claim 4, characterized in that
the detection means is placed at least partly in the box (8). Wire treatment device (1) according to claim 4 or 5, characterized in that
the detection means analyzes the geometry of the web in the recovery window. Wire treatment device (1) according to claim 6, characterized in that
the detection means comprises, on the one hand, illumination means (9), placed on one side of the conveyor belt (5), and on the other hand, an optical detection cell (10) placed the other side of the conveyor belt (5). Wire treatment device (1) according to claim 7, characterized in that
the detection cell (10) comprises a camera. Wire treatment device (1) according to one of Claims 7 to 8, characterized in that
the illuminating means (9) takes the form of a slab, extending substantially parallel to the conveyor belt (5). Wire treatment device (1) according to one of Claims 7 to 8, characterized in that
the illumination means (9) takes the form of at least one elongated light source (11) extending substantially in the direction of movement of the conveyor belt (5). Wire treatment device (1) according to one of Claims 7 to 8, characterized in that
the illumination means (9) takes the form of at least one elongate light source (11), extending substantially parallel to the conveyor belt, transversely to its direction of travel. Wire treatment device (1) according to claim 11, characterized in that
the illumination means (9) takes the form of a pair of elongated light sources (11), each oriented towards the optical detection cell (10). Wire treatment device (1) according to one of Claims 1 to 12, characterized in that
the thread take-up device (6) comprises a regulating means which takes into account the detected position of the ply of threads, in particular in the cooling unit (7), to adjust the speed with which the take-up device (6) ) pulls the strand from the tablecloth. A wire cooling unit (7) for a wire processing device (1) comprising a heat-setting enclosure (3), optionally closed at each of its ends by a sealing head (4) each comprising two rollers, a belt (5) conveyor, on which the yarns are deposited, in bulk or in loops, in the form of a sheet and circulate in the heat-setting enclosure (3), as well as a device for taking up (6) yarn, for pulling the conveyor belt threads (5) after heat setting at a recovery zone which is normally in the cooling unit (7),
said wire cooling unit (7) being intended for fixed mounting downstream of the heat-setting,
characterized in that
it has detection means for detecting the end of the sheet of threads from which the pickup device (6) pulls the threads, and thus check the presence of the pickup area within the pickup window. Detection means, for a wire treatment device (1) comprising a heat-setting enclosure (3), optionally closed at each of its ends by a sealing head (4) each comprising two rollers, a conveyor belt (5), on which the wires are deposited, in bulk or in loops, in the form of a sheet and circulate in the enclosure (3) of heat-setting, and a device for taking up (6) wire, to pull the wires of the carpet (5) conveyor after heat setting, said detecting means for detecting the end of the sheet of yarns from which the recovery device (6) pulls the yarns, and thus checking the presence of the recovery zone within of the recovery window, characterized in that
the detection means analyzes the geometry of the web in the recovery window.

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