JP2001226841A - Method for piecing and apparatus for setting piecing condition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus capable of improving a piecing shape obtained by a piecing action in an ordinary end breakage and carrying out a secure piecing even if a pieced up section is somewhat thickened in a piecing action in doffing. SOLUTION: In this apparatus for carrying out piecing by winding a yarn constituting a sliver S cut in a draft apparatus 10 on a seed yarn Y, two kinds of parameters Tb and Ta as elapsed times from a specific point of time to be a standard in a piecing action to a redriving of the draft apparatus 10 can be preset and inputted. An elapsed time from a specific point of time to a redriving of a back roller 11 is controlled so that a piecing action in a doffing is shorter than a piece action in an ordinary end breakage. Consequently an amount of sliver removed in the piecing action in the ordinary end breakage is made smaller than that in the piece action in the doffing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for removing a predetermined amount of fibers constituting a leading end portion of a sliver, and then winding and piecing the fibers constituting the sliver around a running seed yarn.

[0002]

2. Description of the Related Art Conventionally, in a spinning machine equipped with, for example, a pneumatic twisting device (pneumatic spinning unit), when a yarn breaks or doffs, a seed yarn drawn from a winding package or a separate seed yarn package is twisted. After passing through the twisting device in reverse and re-driving the stopped drafting device to remove a predetermined amount of the fiber constituting the sliver tip, the running of the seed yarn in the winding direction is started and the twisting device is started. By re-driving, the sliver whose tip has been removed by a predetermined amount is introduced into the twisting device, and the swirling airflow inside the twisting device is used to wind the fiber constituting the sliver around the running seed yarn and perform piecing. What is known is. To pass the seed yarn backward through the twisting device means to insert the twisting device in a direction opposite to the direction in which the seed yarn travels during spinning.

[0003] Such a piecing operation includes a piecing operation performed when a yarn break occurs in a state where the winding package is not fully wound (a piecing operation at the time of normal yarn breakage), and a full winding of the winding package. And a piecing operation (piecing operation during doffing) performed when the package is replaced with an empty take-up tube.

[0004]

In the piecing operation, the timing at which the draft device is re-driven is very important with respect to the reliability of the piecing and the form of the seam. For example, if the rewinding of the drafting device is too early,
The removal amount of the torn sliver tip (the part where the amount of fiber is less than the normal part) is larger than the appropriate amount,
The seam may be too thick. On the other hand, if the re-driving of the drafting device is too slow relative to the timing of re-driving of the twisting device, the removal amount of the sliver tip will be less than an appropriate amount, and the seam will be too thin or piecing will fail. There is. If the thickness of the joint is not normal as described above, thread breakage may occur in a subsequent process, or the appearance of the portion may be affected.

[0005] In the piecing operation at the time of yarn breakage, the seam is wound up as it is in the winding package. It is necessary to properly maintain the removal amount of the part. On the other hand, at the time of doffing, the seam portion is sucked and removed in the doffing operation, so that it is required to connect the joint more securely than the form of the seam. However, in the conventional piecing operation, the re-driving of the drafting device is performed after a certain period of time has passed from a specific reference point, regardless of whether the piecing operation is normally performed at the time of thread break or doffing. It was done. Therefore, at the time of doffing, although strict timing is not required, the drafting device may be re-driven at the same timing as at the time of thread breakage where the seam should not be too thick, and piecing may fail. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is intended to improve the shape of the seam normally obtained by the piecing operation at the time of yarn breakage, and to make the seam slightly thicker in the piecing operation at the time of doffing. It is an object of the present invention to provide a method and apparatus capable of performing reliable piecing.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, the sliver is cut after removing a predetermined amount of a fiber constituting a tip portion of the sliver, and then travels. In the method of winding and piercing the fiber constituting the sliver around the seed yarn, the removal amount of the sliver is changed between the piecing operation at the time of normal yarn breakage and the piecing operation at the time of doffing.

[0008] In the invention described in claim 2, the removal amount of the sliver tip portion in the piecing operation at the time of normal yarn breakage is smaller than the removal amount of the sliver tip portion in the piecing operation at the time of doffing.

According to a third aspect of the present invention, the elapsed time from the reference point in time to the re-driving of the drafting device is shorter in the piecing operation at doffing than in the piecing operation at normal yarn breakage. And

According to a fourth aspect of the present invention, as a preparation step for the piecing operation, the seed yarn is passed back through the twisting device, and the draft device is driven again before the twisting device is driven again. It is assumed that the re-driving timing of the draft device with respect to the re-driving timing is faster in the piecing operation at doffing time than in the piecing operation at normal yarn breakage.

According to a fifth aspect of the present invention, there is provided an apparatus for removing a predetermined amount of fibers constituting a tip portion of a sliver cut in a draft device, and then winding and piecing the fibers constituting the sliver around a running seed yarn. Is characterized in that a plurality of values can be set as parameters relating to the removal amount of the sliver tip.

According to a sixth aspect of the present invention, the parameters relating to the removal amount of the tip of the sliver can be separately set for the piecing operation at the time of normal yarn breakage and the piecing operation at the time of doffing.

According to a seventh aspect of the present invention, there is provided a drafting device for a specific point in time which is a reference for the piecing operation at the time of yarn breakage and the piecing operation at the time of doffing, based on the set parameter relating to the removal amount of the sliver tip. Can be changed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings, but the present invention is not limited to the embodiments without departing from the spirit of the present invention.

The present embodiment relates to a spinning machine having a pneumatic twisting device 17 for generating and winding a real twisted spun yarn Y from a sliver S. First, the configuration of the main part of the spinning machine will be described with reference to FIG. Reference numeral 10 denotes a draft device, which is a middle roller 13 having a back roller 11, a third roller 12, and an apron belt 14 in order from the upstream side.
And a front roller 15. The sliver S supplied from the sliver guide 16 on the upstream side of the back roller 11 is stretched at a predetermined stretching ratio by a peripheral speed difference between the rollers of the draft device 10, and then the twisting device ( (Spinning section) 17. A second sliver guide 16a is provided between the third roller 12 and the middle roller 13 (a position where the sliver S is torn when the spinning is stopped).

The twisting device 17 twists the fiber bundle F (sliver S stretched to a predetermined thickness) introduced from the draft device 10 to generate a spun yarn Y. Hollow guide shaft 25 having a thread passage above
And a nozzle hole 21 for generating a swirling airflow near the tip of the hollow guide shaft body 25 (spinning point).
The nozzle hole 21 is formed in the spinning nozzle 22, and the spinning nozzle 22 is formed with a guide hole 20 for guiding the fiber bundle F introduced from the fiber introduction port to the front end entrance of the hollow guide shaft 25. A guide member (needle) 18 is provided at the outlet of the guide hole 20 so as to protrude toward the downstream side such that the front end faces the front end entrance of the hollow guide shaft body 25.

The spinning nozzle 22 is held by a nozzle block 24, and the hollow guide shaft 25 is held by a holding member 26. By fitting the nozzle block 24 and the holding member 26, an air chamber 23 is provided around the hollow guide shaft 25. Is formed. Nozzle block 24 and holding member 2
6, the distal end portion of the hollow guide shaft body 25 has a peripheral opening with the distal end entrance being the nozzle hole 2.
It is inserted into the spinning nozzle 22 until it reaches the vicinity of the first injection position. An actuator (not shown) is connected to the holding member 26, and when spinning is stopped (at the time of yarn breakage), the holding member 26 moves to move the hollow guide shaft 25 to the spinning nozzle 22.
To be separated from.

The fiber bundle F drawn by the draft device 10
Is guided along the guide member 18 from the guide hole 20 and then drawn into the hollow guide shaft 25. The rear end of the fiber, for which the nip at the front roller 15 has been released, is swirled by the swirling flow jetted from the nozzle hole 21 and is turned around and wound around the front end of the hollow guide shaft 25.
It is drawn while being wound around the fiber introduced into 5. In this way, among the many fibers (fibers) constituting the fiber bundle F, the real twisted spun yarn Y in which most of the fibers are wound fibers is generated. The generated spun yarn Y is supplied to a twisting device 17
Is sent downstream by a yarn feeder on the downstream side, and is wound up by a winding package (not shown). The yarn feeder is
It is composed of a delivery roller 28 that is positively rotated, and a nip roller 29 that is driven to rotate in contact with the roller 28, so that the spun yarn Y is nipped and fed between the rollers 28, 29.

Next, the piecing operation normally performed at the time of thread breakage and doffing will be described with reference to FIGS. The normal thread breakage is a thread breakage in a state where the winding package has not reached full winding. For example, when the yarn being spun or wound is cut off naturally due to nozzle clogging (natural yarn breakage) or This refers to the case where the yarn is forcibly cut by detecting the yarn defect. That is,
Usually, the piecing operation at the time of yarn breakage is to pull out the seed yarn from the winding package, and is a piecing operation without doffing operation, and a seam portion due to the piecing is wound into the winding package.

On the other hand, the piercing operation performed at the time of doffing is a piercing operation performed when the winding of a new core tube (bobbin) is started after the winding package reaches a predetermined winding amount and is replaced. is there. In the doffing operation, since the seed yarn is drawn out from another seed yarn package different from the winding package, the running yarn having a predetermined length including the seam portion is suctioned and removed after the piecing is completed. Therefore,
The seam is not wound around a new core tube (winding package).

When the need for thread breakage or doffing arises and the thread breaks (a state requiring piecing), some of the draft rollers constituting the draft device 10 are stopped, and the draft downstream of the draft roller 10 is stopped. The driving state of the roller is maintained. In this example, the back roller 11 and the third roller 12 are stopped, and the driving state of the middle roller 13 and the front roller 15 is maintained. As a result, when the yarn breaks, as shown in FIG. 5, the sliver S is torn by the driven middle roller 13 (apron belt 14), and the leading end portion Sa of the sliver S is moved to the third roller 12 as shown in FIG.
And stops at a position between the roller and the middle roller 13.
At this time, the tip Sa of the sliver S is supported by the second sliver guide 16a.

The driving of the twisting device 17 (pressurized air injection from the nozzle holes 21) is also stopped a little later than the stop of the draft roller described above, and the hollow guide shaft 25 is moved to a position separated from the nozzle block 24. Be moved. Along with the operation at the time of stopping the spinning as described above, the spinning unit operates the notification means to notify the piecing device of the necessity of the piecing operation. After that, using the piecing device that has detected this, the seed yarn on the winding side and the fiber bundle F on the spinning side are used.
(Piecing operation). The piecing device is mounted on a work vehicle that can travel along the spinning unit, and stops at the spinning unit on which the notification unit has been activated to perform the piecing operation.

When the piecing device arrives at the yarn breakage stopping unit, the nip roller 2 is moved prior to the piecing operation.
9 is separated from the delivery roller 28. In the piecing operation, the twisting device 17 is held in a state in which the spun yarn Y (seed yarn) on the winding side is held by the yarn feed roller 30 constituting the yarn transport member and is passed between the nip roller 29 and the delivery roller 28. Conveyed to the yarn discharge side. Then, the seed yarn is sent toward the distal end entrance direction of the hollow guide shaft body 25 by the rotation of the yarn feed roller 30 and the airflow from a nozzle hole (not shown), and is passed through the yarn passage of the hollow guide shaft body 25 in reverse. (See FIG. 2).

Thereafter, the holding member 26 holding the hollow guide shaft 25 is fitted into the nozzle block 24 again. In this state, the yarn end of the seed yarn jumps out of the guide hole 20 of the spinning nozzle 22 by the rotation of the yarn feed roller 30 and the action of the air flow, and the suction provided between the spinning nozzle 22 and the front roller 15. It is sucked and held by the tube (holding means) 34 (see FIG. 3). In this way, the reverse passing of the seed yarn Y through the twisting device 17 is completed. At this time, the air shower tube 3 is located at a position facing the suction tube 34 across the yarn path.
2 is provided to guide the yarn end of the seed yarn jumping out of the guide hole 20 to the suction pipe 34 by the jet air.

Further, the draft rollers (the back roller 11 and the third roller 12) which have been stopped are driven again, and the sliver S (fiber bundle F) is sent downstream through the apron belt 14 and the front roller 15. At this time, the driving of the twisting device 17 remains stopped, and the tip portion Sa of the sliver S is guided by the jet air of the air shower tube 32 and is sucked and removed by the suction tube 34 below.

While holding the seed yarn Y and removing (discharging) the fiber bundle F from which the sliver S has been extended into the suction tube 34, the yarn feed roller 30 is released from the yarn path (the nip is released). At the same time, the yarn feeder (delivery roller 28 and nip roller 29) starts running in the winding direction of the seed yarn Y, and re-drives the compressed air jet from the nozzle hole 21 (spinning nozzle ON), so that the seed yarn Y The fibers constituting the fiber bundle F are wound around the outer periphery, and spinning is resumed (piecing).

As shown in FIG. 4, various actuators related to the piecing operation are controlled by operation signals from a control device 31. In FIG. 4, the draft device 10
The re-drive actuator 32 is an electromagnetic clutch that turns on and off the rotation of the back roller 11. The seed yarn running start actuator 33 is an electromagnetic valve for switching between nip and release of the yarn feed roller 30 and an electromagnetic valve for switching between contact and separation of the nip roller 29 with respect to the delivery roller 28. The twisting device 17 re-driving actuator 34 is an electromagnetic valve for switching the compressed air injection from the nozzle hole 21. The air shower stop actuator 35 is an electromagnetic valve for switching air injection from the air shower pipe 32.

The setting input means 36 provides the controller 31 with various actuators 32 related to the piecing operation.
The operation timings of .about.35 are set and input. The reference timing detecting means 37 is for detecting a specific time point serving as a reference for operating the various actuators 32 to 35 during the piecing operation. The control device 31 performs timer counting based on the input of the reference timing detection signal, and outputs operation signals for various actuators. In this example, the reference timing detecting means 37
It is a detector that detects that the piecing operation cam (not shown) has rotated to a specific angle. The cam for piecing operation is a cam fixed to a drive shaft for driving a driving member such as a yarn conveying member. By arranging a detector such as a proximity sensor near the cam, the piecing operation is performed. Reference timing can be input to the control device 31.

In the present embodiment, a plurality of parameters relating to the sliver removal amount to the suction pipe 34 during the piecing operation can be set and input by using the setting input means 36, and the suction is normally performed at the time of thread breakage and doffing. The sliver removal amount for the pipe 34 can be changed.
The setting input means 36 and the control device 31 constitute a piecing condition setting device.

The sliver S removal amount is determined by the draft device 1
It is determined by the redrive timing of 0 and the redrive timing of the twisting device 17. In this example, the re-driving timing of the twisting device 17 is fixed with respect to a specific reference, and the re-driving timing of the draft device 10 is made different between the normal yarn breakage and the doffing time. In addition to improving the seam form obtained by the piecing operation at the time,
Reliable piercing can be performed during doffing.

After the draft device 10 is driven again, the fiber bundle F that has exited the front roller 15 is sucked and removed by the suction pipe 34 below when the twisting device 17 is not operated. At the moment when the drive of the is restarted, the suction force generated in the introduction port thereby starts to enter the twisting device 17. Therefore, the draft device 10 is re-driven before the twisting device 17 is re-driven. However, if the re-drive timing of the draft device 10 is advanced, the fiber bundle F (sliver S) exiting the front roller 15 is increased. Is the twisting device 17
Will be removed by suction for a long time until it is re-driven, and the removal amount will increase. Conversely, if the re-drive timing of the draft device 10 is delayed, the suction removal time will be shorter and the suction removal amount will be smaller.

In this example, as shown in FIG. 5, in the piecing operation during doffing, the time Ta
After the lapse of time, the back roller 11 is driven again, but in the piecing operation at the time of normal thread breakage, the back roller 11 is driven again after a lapse of time Tb (> Ta) from the reference timing. As described above, by making the re-driving timing of the draft device 10 earlier at the time of doffing than at the time of normal yarn breakage, as described above, the sliver removal time (after the fiber bundle F has exited the front roller 15). , The time until the compressed air injection from the nozzle hole 21 is restarted). The longer sliver removal time is due to the following reasons:
The thick part at the seam due to piecing becomes longer.
That is, although the tip portion Sa of the torn sliver S has a smaller fiber amount (lower density) than the other portions, the removal amount of the tip portion Sa is larger than the other portion. This means that the overlapping portion between the (normal density portion) and the seed yarn increases. Therefore, the thick part at the joint becomes longer.

On the other hand, in the piecing operation at the time of normal yarn breakage, the re-driving timing of the drafting device is delayed as compared with the doffing operation, so that the removal amount of the sliver tip portion Sa is reduced, and the thick portion at the seam due to piecing is removed. Be shorter. Therefore, there is no adverse effect on subsequent processes such as the weaving and knitting process, and no undesirable pattern is produced in the final fabric product.

As described above, in the present embodiment, the seed yarn Y
After being passed back through the twisting device 17 and removing the leading end Sa of the sliver S cut in the drafting device 10 by re-driving the drafting device 10, allowing the seed yarn Y to travel and the twisting device By re-driving 17
In the device for piecing by winding the fiber constituting the sliver S around the seed yarn Y, a parameter relating to the removal amount of the sliver tip portion Sa during piecing (elapsed time from a specific point in time as a reference until the draft device 10 is driven again) As two types of parameters Tb and Ta for normal thread breakage and doffing can be set and input in advance, the piecing operation and the ball for normal thread breakage are performed based on these two parameters Tb and Ta. The removal amount can be changed by the piecing operation at the time of lifting, and the piecing operation at the time of doffing can be reliably performed without error while maintaining a good seam shape in the piecing operation at the time of normal yarn breakage.

The timing at which the draft device is driven again is controlled by the elapsed time from when the rotating cam, which is the driving source of the piecing operation, reaches a specific angle.
Another operation (driving) in the piecing operation is detected, and the timing can be controlled based on the detected time. In addition, as the parameter relating to the removal amount of the sliver tip portion, the elapsed time from the reference time to the time when the draft device is re-driven is set and input. Time to be removed by suction tube before re-driving
May be set and input, and the drive timing in the piecing operation may be calculated based on the set time.

In the above description, the boundary between the sliver S and the fiber bundle F is not always strict, that is, the area defined as the fiber bundle F is not strict, and at least the back roller 11 of the draft device 10 The sliver S may be defined on the more upstream side, and the spun yarn Y may be defined on the downstream side of the twisting device 17.

[0037]

The present invention is configured as described above.
The following effects are obtained. According to the present invention, the removal amount of the tip of the sliver in the piecing operation can be changed between the normal yarn breakage and the doffing. The piecing operation can be reliably performed even if the seam is slightly thickened during doffing while maintaining a good seam form in the piecing operation. Therefore, it is possible to reduce piecing mistakes in the piecing operation during doffing and improve the operating efficiency.

[Brief description of the drawings]

FIG. 1 is a schematic side sectional view showing a state during spinning in an embodiment of the present invention.

FIG. 2 is a schematic side sectional view showing a state during the piecing operation.

FIG. 3 is a schematic side sectional view showing a state during the piecing operation.

FIG. 4 is a block diagram including a piecing condition setting device.

FIG. 5 is an explanatory diagram showing the timing of each operation in the piecing operation.

[Explanation of symbols]

F: fiber bundle, S: sliver, Sa: tip, Ta: parameter for doffing, Tb: parameter for normal thread breakage,
Y: spun yarn (seed yarn), 10: draft device, 11: back roller, 17: twisting device, 31: control device, 36: setting input means

Claims (7)

[Claims] 1. A method for removing a predetermined amount of fibers constituting a tip portion of a sliver cut in a draft device, and then winding and piecing the fibers constituting the sliver around a running seed yarn. Wherein the sliver removal amount is changed between the piecing operation and the piercing operation during doffing. 2. The piecing method according to claim 1, wherein the removal amount of the sliver tip portion in the piecing operation at the time of normal yarn breakage is smaller than the removal amount of the sliver tip portion in the piecing operation at the time of doffing. 3. The piecing method according to claim 2, wherein an elapsed time from a specific point in time as a reference to a time when the draft device is re-driven is shorter in the piecing operation at doffing time than in the piecing operation at normal yarn breakage. . 4. A method for preparing a piecing operation, in which a seed yarn is passed back through a twisting device and a draft device is re-driven prior to re-driving of the twisting device. 3. The piecing method according to claim 2, wherein the re-driving timing of the device is earlier in the piecing operation at doffing time than in the piecing operation at normal yarn breakage. 5. An apparatus for removing a predetermined amount of fibers constituting a tip portion of a sliver cut in a draft device, and then winding and piecing the fibers constituting the sliver around a running seed yarn, the device comprising: A piecing condition setting device, wherein a plurality of values can be set as parameters relating to a removal amount. 6. The piecing condition setting device according to claim 5, wherein a parameter relating to a removal amount of a sliver tip portion can be separately set for a piecing operation at the time of yarn breakage and a piecing operation at doffing. 7. A re-driving timing of the draft device with respect to a specific point in time which is a reference for the piecing operation at the time of normal thread breakage and the piecing operation at the time of doffing based on the set parameter relating to the removal amount of the sliver tip portion. 7. The piecing condition setting device according to claim 6, wherein the piecing condition setting device is enabled.