JPH03174054A - Method for weaving in fluid jet loom - Google Patents

Abstract

PURPOSE:To obtain high-quality cloth without causing bright speck defects in high-speed weaving of especially high-elongation yarn by controlling operation of a weft yarn gripper so as to open simultaneously with picking, close the operation simultaneously with completion thereof and reopen during the reed beating. CONSTITUTION:A rotating cam 11 of a gripper 7 is driven just before starting picking and the back end of a lever 12 is pushed with a high ridge part thereof to float an upper nipping unit 13 and open the holding of weft yarn (B). At the time of completing the picking, the aforementioned cam 11 is rotated from the high ridge part to a low part and the above-mentioned lever is subsequently returned by action of springs 15 and 16 to sink the upper nipping unit 13, bring the lower nipping unit 14 into pressure contact therewith, hold and fix the weft yarn (B). The rotating cam 11 is then rotated from the low part to the high ridge part during the reed beating and the holding of the weft yarn is reopened in the same manner as described above. The aforementioned operation is repeated for each weaving cycle to prevent an abnormal tension from applying to the weft yarn (B).

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to weft insertion in a fluid jet loom.

More specifically, the present invention relates to a weft tension relaxation method for suppressing an increase in weft tension during beating.

[Conventional technology]

When manufacturing textiles using high-elongation weft yarns on fluid-jet looms such as water jet looms, the current situation is that the rotational speed is usually lowered to improve weft quality, even though the looms are high-speed looms. . Weaving in a water jet loom involves inserting the weft yarn into the warp opening using a jetting fluid, driving it into the mh using a reed, and then cutting the yarn extending between the nozzle and the fabric edge with a cutter. A series of waiting movements is repeated so that weft insertion can be carried out without any problems. When weft insert weaving is performed using a water jet loom and high elongation yarn is used as the weft, sink marks occur on the fabric surface on the nozzle side under normal conditions. This is especially noticeable during high-speed weaving, and there is a problem in that it becomes a sink defect.

[Problem to be solved by the invention]

The inventors of the present invention have conducted extensive studies on the causes of such problems, and have found that when the weft yarn is driven by a reed, a large strain is gradually applied to a part of the weft yarn after the reed passes just in front of the nozzle. It has been found that sink marks occur. Further studies have led to the present invention, which reduces the large strain applied to the weft yarns on the nozzle side during beating. The present invention aims to provide a weft tension relaxation method that has excellent high-speed weaving properties and can stably obtain high-quality fabrics.

(Means for Solving the Problems) When weaving using a fluid jet loom having a gripper opening/closing mechanism, the present invention opens the gripper at the same time as weft insertion, closes the gripper at the end of weft insertion, and then closes the gripper again during beating. This weaving method is characterized by opening the gripper.

The means for controlling the gripper in the present invention is not particularly limited.

It may be mechanical such as a cam or lever, electrical such as an encoder, or a combination of both that extracts a signal from the crankshaft.

The weft insertion mechanism of a water jet loom that mechanically controls the gripper using the method of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing the main parts of the weft inserter.

The warp threads (1) are divided into upper threads and lower threads by the shedding movement of the heddles (2), and are opened at the position of the nozzle (6) at the rear of the weave (C). Weft (B) unwound from weft supply body (A)
The length measuring roll and presser roll that rotate in conjunction with the loom (
3), and is sent out at a constant speed, stored in a storage rotating drum (4), and placed on standby. Next, at approximately the same time that the fluid sent out from the plunger (5) is jetted from the jet nozzle (6), the gripper (7) opens and the weft (B) is moved into the warp opening by the jetted fluid without being restrained. It is inserted and held by the catch cord (8) on the anti-nozzle side.

Then, the gripper (7) is closed at the same time as it is gripped by the catch cord (8), gripping and fixing the weft (B). The weft yarn (B) that has been continuously inserted is driven into the fabric front (C) from the position of the nozzle (6) by the reed (9), but during this driving, the gripper (7) is opened again to remove the weft binding. . When the weft (B) is driven to form the woven fabric (D), the weft (B) is cut by cutters 00) provided at both ends of the woven fabric (D).

FIG. 2 shows a schematic diagram of an example of using the method of the present invention, enlarging the mechanism of a mechanical gripper (7). Immediately before the start of weft insertion, the gripper (7) releases the weft (B) that has been gripped and fixed by lifting the upper gripper 0 using the high peak of the rotary cam OD and the lever q7J. Next, immediately after weft insertion, the rotary cam rotates from a high peak to a low part, is actuated by a lever (121 is a spring Q5, Q6), and the upper clamping body 03) sinks and comes into pressure contact with the lower clamping body 04), and the weft Grasp and fix (B). The reed (9) then moves forward and passes the position of the nozzle (6). During the reed beating, the rotary cam 01) rotates from the high mountain part to the low part, and changes the weft from the start of weft insertion to the weft part (C). The same mechanism as that used until the end of the weft operation operates to open the gripper (7) to release the weft, and grip and fix it again just before the beating ends.

By doing as described above, no abnormal tension is applied to the weft (B), and as a result, a weaving method that does not cause sink defects can be obtained.

〔Example〕

Hereinafter, this will be explained in detail using examples.

The evaluation method was as follows.

Regarding weaving performance, when weaving 2,000 m with a general tack, weft breakage stopped once/day is ◎, and 2 to 3 times/day is ○.
And so. In addition, regarding the quality of the gray fabric and workability, those with no sink marks were rated as ◎, those with some O1 were rated as ×, and those with noticeable sink marks were rated as XX.

Examples 1 to 4 and Comparative Examples 1 to 3 Highly elongated polyamide filament yarn 70d/24f with a breaking elongation of 60% spun at 4000 m/min was used as the weft, and water jet loom (Tsudakoma Industries ■Product name ZL30) was used.
In step 3), weft insertion was evaluated. The results are summarized in Table 1. Using a conventional gripper opening/closing mechanism, the loom rotates 50
When weaving at 0 rpm, significant sink defects occurred on the fabric surface on the nozzle side in both the gray fabric and the degree of processing regardless of the warp thread width (Comparative Examples 2 and 3). However, in the example of the gripper opening/closing mechanism using a mechanical rotary cam using the method of the present invention, even if the warp thread width is increased, a high-quality fabric with no sink defects on the fabric surface on the nozzle side can be produced at a loom rotation speed of 80 rpm. (Example 3). It was also confirmed that the reed abrasion resistance was significantly improved. FIG. 3 is a graph showing the relationship between the weft tension and the crank angle, which is amplified and recorded on an electromagnetic oscilloscope by an amplifier using a weft tension measuring device set between the gripper and the injection nozzle. The dotted line shows a conventional gripper opening/closing mechanism, and the solid line shows an example of a gripper opening/closing mechanism using a mechanical rotary cam using the method of the present invention.

In the gripper opening/closing mechanism of the present invention, the tension (
The tension (T3) applied when the gripper is opened at T, ) and switched from free flight to restrained flight at 235 degrees. Then, 27
Weft insertion is completed at 0 degrees and the tension (T
4) is added.

Further, in the method of the present invention, beating proceeds with the gripper open at 275 degrees and the tension is reduced, and ends with the gripper closed at 350 degrees.

However, in the conventional gripper mechanism, beating is performed while the weft is gripped and fixed by the gripper, so there is a tension (rs) applied during beating afterwards, which causes sink defects that occur on the fabric surface on the nozzle side. . In an example of a gripper opening/closing mechanism using a rotary cam using the method of the present invention, the graph shape of the weft tension is the same as the conventional one from (TI) to (T4), but the tension (T, ) applied during beating is This eliminates the presence of sink marks and eliminates them.

Table [Effects of the Invention] By using the method of the present invention, it is possible to eliminate sink defects on the nozzle side that occur especially during high-speed weaving of high-elongation yarns, obtain high-quality fabrics, and reduce reed abrasion during weaving. This has the effect of greatly improving the performance.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the main part of the weft insertion in the water jet loom, Fig. 2 is a schematic diagram of the mechanism for controlling the movement of the gripper of the present invention, and Fig. 3 is a diagram showing the relationship between weft tension and crank angle. It is a graph showing the relationship. T1... Tension at the start of injection, T2... Tension during flight,
T. ...Tension at the end of free running, T4...Tension at the end of weft insertion, T1...Tension at the end of beating, solid line...Tension when using the method of the present invention, dotted line...・Tension when using the conventional method, A... Weft supply body, B... Weft, C...
- Orimone, D... woven fabric, 1... warp, 2... heddle,
3... Length measuring roll and presser roll device, 4... Storage rotating drum, 5... Plunger, 6... Injection nozzle, 7... Gripper, 8... Catch cord, 9...
・Reed, 10... Cutter, 11... Rotating cam, 12.
...Lever 13...Upper clamping body, 14...Lower clamping body, 15.16...Spring.

Claims (1)

[Claims] 1. A weaving method when weaving using a fluid jet loom having a gripper opening/closing mechanism, in which the gripper is opened at the same time as weft insertion, the gripper is closed at the end of weft insertion, and the gripper is opened again during beating. .