JPH04241144A - Starting of weaving machine - Google Patents

Abstract

PURPOSE:To surely prevent deficiency of length of woven fabric caused by shrinkage of weft by reversely operating a weaving machine having finished weft inserting to remove bad weft, inserting dummy yarn, reversing the weaving machine, idling and starting. CONSTITUTION:A jet loom having finished weft inserting is reversed to remove bad weft, dummy yarn is inserted into a weft inserting side in a warp opening or a weft inserting side or both the sides. The dummy yarn has length corresponding to selvage texture of woven fabric having about 5-10mm, about 1-2cm at longest and the final weft subjected to weft inserting is firmly restricted by warp through the dummy yarn by reversing the weaving machine just before occurrence of bad weft inserting. The dummy yarn is removed when a weaving machine is restarted and then warp restricts the final weft or after weaving is completed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for starting a loom in a jet loom, which effectively prevents fabric defects from occurring due to shrinkage of weft yarns when restarting a loom that has stalled.

0002

2. Description of the Related Art When a highly contractile weft yarn is used in a jet loom, fabric defects may occur due to shrinkage of the weft yarn when the weft is restarted after the weft has come to rest.

[0003] In order to remove the defective weft yarn that caused the weft to stall, the loom first performs one rotation of reverse operation after stopping, thereby releasing the defective weft yarn from being restrained by the warp (so-called reverse start-up). motion). Therefore, after removing the defective weft yarns, the loom is reversed about one rotation, the loom is set at a predetermined starting angle, and then starting from this starting angle is performed. At this time, the first reed beating after startup is performed without weft insertion, so-called dry beating, and the second and subsequent reed beatings are actual reed beating. This starting method is widely known as a so-called dry beating start, and according to this method, the first reed beating, which tends to lack the reeding force, is a blank beating, so it is possible to prevent the occurrence of weaving steps. It can be effectively prevented.

However, when such a starting method is used, the warp shedding opens when the reverse operation is completed after removing the defective weft, and the weft that was normally inserted just before the loom stops (hereinafter referred to as the final weft) is , the binding force of the warp yarns is lost, so the final weft yarns may shrink and create new fabric defects. This type of fabric defect is particularly noticeable when using highly shrinkable weft yarns such as high twist yarns or spandex yarns.

[0005] Therefore, as a countermeasure to this problem, a technique using an ear-closing device is known (Japanese Unexamined Patent Publication No. 62-2
06059). This device temporarily disconnects the selvage tying device from the main shaft when performing a reverse operation after removing defective weft yarns, or even if the selvedge tying device reverses in conjunction with the main shaft.
In order to prevent the influence from reaching the binding point of the weft yarn by the selvage yarn,
By introducing a kind of twist stopping device, the final weft is kept restrained by the selvedge yarn, and its shrinkage is prevented.

[0006]

SUMMARY OF THE INVENTION This prior art technique requires a selvage thread device, so there is a problem in that it cannot be applied to a loom that does not use this device. Furthermore, there is also the problem that it is not always possible to sufficiently prevent the shrinkage of the weft yarns, making it difficult to completely prevent the occurrence of fabric defects. In other words, the final weft at this time is restrained by the upper selvage thread and the lower selvage thread crossing once between the reed and the woven fabric, but the position of this crossing point is Because the distance from the selvage device to the selvage device is long, it tends to be far away from the fabric. Therefore, the restraining force obtained is only weak, and it is difficult to strongly hold highly twisted yarns, spandex yarns, etc. against the tension.

Therefore, in view of the actual state of the prior art, an object of the present invention is to remove the defective weft yarns and then insert dummy yarns into the warp openings, thereby eliminating the need to use a selvage device and making the weft yarns strong. To provide a method for starting a loom, which can obtain a binding force to hold twisted yarns, spandex yarns, etc. sufficiently stably, and can effectively prevent fabric defects caused by shrinkage of weft yarns. be.

[0008]

[Means for Solving the Problems] The configuration of the present invention to achieve the above object is such that when restarting a loom that has stopped weft, the loom is reversed to remove defective weft yarns, and then a dummy yarn is inserted into the warp opening. The gist is to insert the loom, reverse the loom, set it at a predetermined starting angle, and start it.

The dummy yarn may be removed after the loom is started and when the warp binds the final weft, or may be removed after weaving.

[0010] Furthermore, the dummy yarn may be inserted into the warp opening with a length corresponding to the selvedge tissue of the woven fabric.

[0011]

[Operation] With this configuration, the dummy yarn is inserted into the warp opening in place of the defective weft after removing the defective weft, so even if the loom is then reversed and set at a predetermined starting angle, The final weft can be firmly restrained by the warp via a dummy thread. That is, the final weft is
It receives necessary and sufficient binding force and there is no risk of inadvertent contraction.

[0012] Furthermore, since the final weft generally tends to shrink on the weft insertion side, the dummy yarn should have a length of about 5 to 10 mm, or at most 1 to 2 cm, on the weft insertion side of the woven fabric. It is sufficient to insert it into the warp opening. Also,
The dummy yarn may be inserted on any one or both of the weft insertion side and the anti-weft insertion side of the woven fabric.

[0013] As the dummy thread, weft threads for weaving can be used as they are, or special threads different from weft threads or thin wires made of metal or synthetic resin can also be used. When yarn is used, it may be removed after weaving, or it may be removed automatically after the loom is started and when the warp binds the final weft. When using a thin wire other than thread, it is best to automatically remove it after startup and use it repeatedly.

[0014] If the insertion length of the dummy thread is set to a length corresponding to the selvedge tissue of the woven fabric, it is extremely easy to remove the dummy thread from the woven fabric because the length of the dummy thread is short. Even if a dummy thread made of thread is left unremoved, it is extremely unlikely to cause a fatal defect to the woven fabric.

[0015]

[Embodiment] An embodiment will be explained below with reference to the drawings.

The method for starting the loom is carried out by attaching a dummy thread insertion device 10 to the weft insertion side of the woven fabric W in a water jet loom or an air jet loom (see Fig. 1).
).

The warp threads P, P, . . . are opened according to a predetermined opening pattern by a heald frame (not shown). Also,
The weft F is inserted into the warp opening by a water jet or an air jet through a weft insertion nozzle (not shown),
A woven fabric W can be woven by being driven into the woven fabric Wa by a reed (not shown). In addition, the inserted weft F
is cut by the yarn feeding cutter CT for each pick.

The dummy yarn insertion device 10 is disposed on the weft insertion side of the woven fabric W, and has a driving roller 11 and a feeding roller 1.
2. A guide 13 is provided. The drive roller 11 is connected to a drive source 11a such as a reversible motor or a rotary solenoid, and the drive source 11a can drive the drive roller 11 forward or backward by a predetermined rotation angle. The feed roller 12 is in pressure contact with the drive roller 11, and one end of a dummy thread Q made of a thin flexible metal or synthetic resin wire is fixed to the surface thereof. The dummy yarn Q is inserted through the guide 13, and its tip faces the warp opening at a position very close to the fabric front Wa.

Therefore, when the driving roller 11 is driven in the direction of arrow A1 in FIG. 1 by the drive source 11a, the feeding roller 12 rotates in the direction of arrow A2 in the same figure, so that the dummy yarn Q is moved in the direction of arrow A3 in the same figure. direction, and its tip can be inserted into the warp opening. Note that the rotation angle of the drive roller 11 is determined so that the insertion length of the dummy yarn Q at this time is a predetermined constant length. Further, by driving the drive roller 11 in the direction opposite to the direction of arrow A1, the dummy yarn Q can be removed from the warp opening.

Now, when the loom is in steady operation, if a weft insertion failure occurs in loom cycle Ko (FIG. 2), a stop signal from a weft feeler (not shown) causes the loom to start the next operation after coasting. loom cycle K1
The weft stops at . At this time, the warp threads P, P...
Including defective weft Fb, final weft Fa, final weft Fa
All of the weft yarns F, F, etc., which were previously inserted normally, are restrained and opened according to the shedding pattern in the loom cycle K1 (FIG. 3(a)).

Subsequently, the loom performs one rotation of reverse winding (FIG. 2). When the reverse lead-out is completed, the warp P
, P... releases the restraint of the defective weft Fb (Fig. 3
(b)), the defective weft Fb can be removed from the warp shedding manually or automatically by a defective weft removal device (not shown) (FIG. 2(c)).

Next, the dummy thread insertion device 10 is driven,
Insert the dummy thread Q into the warp opening (Fig. 2, Fig. 3(d))
. Next, the loom is reversed about one rotation and the loom is set at a predetermined starting angle in starting cycle K-1 (Figure 2).
, the warp threads P, P... are opened according to the shedding pattern in the loom cycle K-1, so the dummy thread Q is the warp thread P, P...
(Fig. 3(e)). That is, the final weft Fa at this time can be firmly restrained by the warp threads P, P... via the dummy thread Q, at least in the range where the dummy thread Q exists, so the warp threads P, P...,
The dummy yarn Q can effectively prevent the final weft Fa from shrinking toward the inside of the woven fabric W from the weft insertion side. Note that during this reversal process, the yarn feeding cutter C
When T operates in conjunction with the loom, it shall be temporarily inoperative so as not to cut the dummy thread Q.

Next, the loom is started by a start signal,
After one dry run, the loom returns to normal operation (Figure 2
). At this time, just before the blank beating, the warps P, P... are closed, and the final weft Fa, weft F, F by the warp P, P...
When the restraint of ... is achieved, the dummy yarn Q is removed from the warp opening (FIGS. 2 and 3(f)). Thereafter, in the loom cycle Ko, the loom inserts a new weft F to replace the defective weft Fb (Fig. 3 (g)), and actually strikes this weft F (Fig. 2), thereby correcting the weft insertion defect. hand,
The weaving operation of the woven fabric W can be continued.

[0024]

[Other Embodiments] The dummy yarn Q can be a yarn supplied from a yarn supplying body Q1 (FIG. 4). The dummy yarn Q is nipped by a drive roller 11 and a feeding roller 12, and is
1, a predetermined length can be inserted into the warp opening via the clamp device 14a and the conveyance nozzle 14. In addition, the yarn feeder Q1, the drive roller 11, and the feeding roller 1
2, a yarn guide 14b is arranged.

Between the nozzle 14 and the woven fabric W, a suction tube 21 connected to a vacuum source, a swing lever 22 for guiding the dummy yarn Q to the suction tube 21, and a dummy yarn A weft removing device 20 including a cutter 23 for cutting the weft yarn is disposed.

After removing the defective weft yarn Fb, the dummy yarn Q can be inserted into the warp opening by operating the drive roller 11 and the feeding roller 12, opening the clamp device 14a, and operating the nozzle 14. . however,
At this time, the swing lever 22 is retracted at a high distance from the suction tube 21 (solid line in FIG. 4).

After starting the loom, move the swing lever 22 to the suction pipe 2.
1 (two-dot chain line in the figure), the dummy yarn Q can be guided to the suction tube 21, and in this state, the cutter 23 is operated to cut the dummy yarn Q. Since the cut dummy yarn Q is suctioned into the suction tube 21, its tip portion is removed from the warp opening and the whole can be disposed of into the suction tube 21. The weft removal device 20 can also be used to remove defective weft yarns Fb by inactivating the yarn feed cutter CT and stopping the loom when a weft insertion failure occurs. In addition, the dummy yarn Q completes the start-up of the loom without being actively removed from the warp shedding,
Weaving may be continued by cutting off the surplus portion by the yarn feeding cutter CT, and after weaving, the surplus portion may be removed.

The dummy yarn Q can also be used by diverting a part of the weft yarn F (FIG. 5). The weft F is a yarn feeder F1
The yarn is unwound from the yarn guide 14b, the drum-type weft length measurement and storage device 15, and the weft insertion nozzle 16, and then inserted into the warp opening. The weft length measuring and storage device 15 moves the drum 1 from the rear of the drum 15b by a rotating yarn guide 15a.
The weft F is wound around and stored on the locking pin 15c,
By retracting the weft 15d from the circumferential surface of the drum 15b, a predetermined length of the weft F can be unwound to the front of the drum 15b.

A weft removal device 20 is disposed between the woven fabric W and the weft insertion nozzle 16. However, here:
The weft removing device 20 has an auxiliary nozzle 21a instead of the swing lever 22, and further includes a pair of rollers 24 and 25 at the tip of the suction tube 21. One roller 24 can be driven in the direction of arrow A4 in FIG. 5 by a drive source 24a, and the other roller 25 can be moved forward toward the roller 24 and pressed against the roller 24 by a cylinder 25a.

When a defective weft insertion occurs, the loom stops at the weft with the operation of the yarn feed cutter CT temporarily stopped, and in this state, the defective weft Fb in the warp shed is transferred to the weft insertion nozzle 16. Continuous. Therefore, by reversing the loom once to release the restraint on the defective weft yarn Fb, actuating the auxiliary nozzle 21a, and cutting the weft yarn F by the cutter 23, the base end of the defective weft yarn Fb is transferred to the suction tube 2.
It can be attracted to 1. Next, the cylinder 25a
By advancing the roller 25 and rotating the roller 24, the defective weft Fb is mechanically pulled out from the warp opening,
It is possible to remove the defective weft Fb.

Next, the weft insertion nozzle 16 is operated, and only the locking pin 15c on the upstream side in the unwinding direction of the weft F on the drum 15b (direction of arrow A5 in FIG. 6) is retracted from the circumferential surface of the drum 15b. By doing so, the weft yarn F on the drum 15b is unwound by a predetermined length corresponding to the arrangement angle θ of the locking pins 15c and 15d, and the tip of the weft yarn F can be inserted into the warp opening. The tip of this weft F can be used as a dummy yarn Q. The rear end portion of the dummy yarn Q is cut by, for example, a yarn feeding cutter CT.

[0032] Thereafter, the loom may be reversed and a blank start may be started in accordance with each of the above-described embodiments. Note that the dummy yarn Q at this time is removed after the woven fabric W is woven. However, the dummy yarn Q is not fed by the yarn feeding cutter CT, but by the cutter 2.
3, the defective weft F will be removed immediately after starting the loom.
It can be mechanically removed from the warp shedding in the same manner as the removal operation in b. In addition, when inserting the weft yarn F as the dummy yarn Q, the weft insertion nozzle 16 requires a weft insertion length that is extremely short. It can be lowered.

In the above explanation, the insertion length of the dummy yarn Q into the warp shedding is generally 5 to 10 mm, and at most 1 mm.
~2 cm is sufficient. In addition, if the insertion length of the dummy thread Q is set to a length corresponding to the width of the selvedge tissue of the woven fabric W, the dummy thread Q can be easily removed, and even if the dummy thread Q is not removed, the woven fabric Compared to cloth W, it has the advantage that there is less risk of fatal textile defects. Furthermore, the dummy yarn Q may be inserted into the warp opening not only from the weft insertion side of the woven fabric W but also from the opposite weft insertion side, or from both the weft insertion side and the opposite weft insertion side. shall be taken as a thing.

[0034]

As explained above, according to the present invention, after the loom in which the weft has stalled is reversed and the defective weft is removed, a dummy yarn is inserted into the warp opening, and then the loom is reversed and the weft is run dry. By starting, the final weft can be firmly restrained by the warp via the dummy thread, so
Even when using weft yarns with strong shrinkage, it is possible to reliably prevent fabric defects caused by shrinkage of the weft yarns.Furthermore, since the selvage yarn device is not used at all at this time, the selvage yarn device can be It has an excellent effect in that it can be effectively applied even to looms that do not have the same technology.

[Brief explanation of the drawing]

[Figure 1] Perspective explanatory diagram of the main parts of the loom

[Figure 2] Diagram explaining operation

[Figure 3] Schematic diagram showing the restraint state of the weft yarn in each movement process

[Figure 4] A diagram equivalent to Figure 1 showing another embodiment

[Figure 5]
A diagram corresponding to FIG. 1 showing another embodiment

[Figure 6] View corresponding to the X arrow in Figure 5

[Explanation of symbols]

P...Warp F...Weft Fb...Defective weft Q...Dummy thread

Claims (4)

[Claims] [Claim 1] When restarting a loom that has stopped weft,
A method for starting a loom, which comprises: reversing the loom to remove a defective weft, inserting a dummy thread into a warp opening, reversing the loom, setting it at a predetermined starting angle, and starting the loom. 2. The method of starting a loom according to claim 1, wherein the dummy yarn is removed when the warp binds the final weft after the loom is started. 3. The method for starting a loom according to claim 1, wherein the dummy yarn is removed after weaving. 4. The method for starting a loom according to claim 1, wherein the dummy yarn is inserted into the warp opening to a length corresponding to the selvedge tissue of the woven fabric.