JPS62206056A - Method for flying weft yarn in air jet loom - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a weft flying method in an air jet loom. More specifically, the present invention relates to a weft flying method in an air jet loom, and more specifically, a method for preventing unraveling on a weft storage drum in an air jet loom equipped with a weft storage drum. The present invention relates to a method of causing a weft to fly by determining the release timing of a fixing pin in relation to the timing of starting injection of pressurized air from a main nozzle.

[Conventional technology]

Along with Air Jet Loom H and Quarter Jet Loom, it is widely used due to its excellent productivity. Conventional air jet loom loom rotation speed is 400-450r,
It has been used in the range of p and m, but due to strong demands from users, even faster types have been developed.
In the above-mentioned jet room, it is necessary to store the length of weft yarn required for one weft insertion before inserting the weft yarn using a jet of air. . Known methods for storing weft yarns include the pool pipe method, which combines a feed roller, a pool pipe, and a gripper, and the rotating drum method, which stores the weft on a rotating drum.However, for high-speed types, the rotating body is placed over a fixed drum. A fixed drum system is mainly used. In this fixed drum system, a fixed bin for preventing weft unwinding is provided on the surface of the fixed drum near the main nozzle side, and when pressurized air is not injected from the main nozzle, this fixed bin protrudes above the fixed bin and is placed on the fixed drum. This prevents the weft threads wound around the material from slipping down.
Pressurized air is injected from the main nozzle to stretch the tip of the weft yarn into the opening formed by the plurality of warp yarns, and then the fixed bin is released and the weft yarn is allowed to fly.

[Problem that the invention seeks to solve]

In an air jet loom in which weft yarns are retained using a fixed drum system, various problems occur regarding the flying of weft yarns, as described below. In other words, since the fixed bin is released after pressurized air is injected from the main nozzle, the weft yarn will fly against the moving bin in order to be released, and as a result, single weft yarns tend to come apart. Variations tend to occur in the timing at which the weft yarns come off the fixed bins, and as a result, variations occur in the flight distance of the weft yarns, which tends to cause misbuck.

The present invention solves the above-mentioned problems in the weft flying method of an air jet loom that employs a fixed drum system, thereby preventing damage such as single yarn looseness to the weft yarn, and reducing the occurrence of misbuck etc. It is an object of the present invention to provide a weft flying method that is capable of weaving fabrics with excellent fabric quality and has high weaving efficiency. The purpose is to unwind the weft yarns stored in the weft storage drum using pressurized air jetted from a main nozzle in an air jet loom that has a weft storage drum, and to make the weft yarns fly into openings formed by a plurality of warp yarns. At this time, the release timing of the unraveling prevention fixing bin on the weft storage drum is made to precede the timing of starting injection of pressurized air from the main nozzle by 5° to 30° based on the crank angle of the air jet loom. This is achieved by the weft flying method in the jet loom.

If the crank angle preceding the release timing is 5° or less, the start of the weft flight and the release timing of the fixed bin will still overlap, and the weft will come into contact with the tip of the fixed bin, causing single yarn looseness. This is not preferable because it causes poor flight performance.

If the preceding angle of the release timing is 300 degrees or more, the weft threads will not be inserted into the warp openings because the opening of the warp threads is not yet sufficient at that point, or the release timing of the fixed bin will be too early. Therefore, at that point, the residual pressure in the main nozzle from one pick ago remains, and there is a risk that the weft yarn may fly out from the main nozzle. In addition, since the fixed bin is located in the large taper part of the fixed drum, if the fixed bin is released too early, the weft yarn in the large taper part will slip down to the small taper part, which is almost parallel, and this will cause the taper to fall. There is no resistance when winding a large part. In this state, when the fixed bin engages with the fixed drum and starts measuring the length of the next weft thread for weft insertion, the unwinding resistance of the weft from the cone is increased by the fixed drum. The weft tends to be transmitted to the weft in the almost parallel part where the taper is small, pulling it and tightening it, and sometimes pulling the weft back from the main nozzle, causing misbic.

Therefore, it is preferable that the crank angle preceding the release timing is between 5° and 30°, particularly when the rotational speed of the loom is 600 to 900 r, p, m, 10'
More preferably, the angle is selected between −15°.

Next, the present invention will be described with reference to the accompanying drawings schematically showing an air jet loom having a fixed drum-type cotton yarn storage drum, which is used when carrying out the weft flying method in an air jet loom according to the present invention.

Figure 5 shows a fixed drum 2 as a weft storage drum, a main nozzle 9 that injects pressurized air that unwinds the next weft 1 stored in the fixed drum 2 and sends it to the frontage of the warp, and the main nozzle 9 is fed. Multiple guides 1 that sequentially transfer the weft threads
The weft inserting mechanism of the air jet loom is shown. The inserted weft is beaten by the reed 10 to complete the weaving. The fixed drum 2 has a tapered portion 4 as shown in FIG. and a substantially parallel portion 3 with a small taper, and one end of a fixing pin 5 for preventing the weft from unraveling is inserted into a hole 6 provided in the radial direction in the middle portion between the two. Winding of the weft yarn l around the fixed drum 2 is shown as a guide 7 in the drawing, but in reality, the yarn is wound from the cone 8 by rotating a rotating body placed over the fixed drum 2 as shown by the arrow. It is done from the drawer residue. In Figure 1lE1, the weft l is shown as having four turns 5 in each of the tapered portion 4 and the small tapered almost parallel portion 3, but in reality, for example, the weft yarn is wound four times in the tapered portion 4 (the solid line When the fixing pin 5 is lifted upward from the hole 6 and the weft is released, the weft appears to be shifted to a substantially planar portion 3 with a small taper (the weft is indicated by a broken line). Also each part 3
, 4 and the taper angle should be appropriately selected depending on the purpose of use of the loom. Detailed explanation will be omitted.

As is well known, in a loom, the timing of action of each component, in this case the main nozzle 9 and the fixing pin 5, is determined based on the rotation of the crankshaft. Before the weft is jetted, the thread 1 is shifted from the tapered section 4 to the substantially flat section 3 by pulling up the fixing pin 5 from the hole 9 between 5° and 30° of the crank angle, whereby the weft Since the weft threads are immediately fed into the warp opening, there is no possibility that the weft threads will come into contact with the fixing pins and cause single threads to come loose (also, there will be no variation in the flight distance of the weft threads, which will reduce the occurrence of misbucks. Examples] Examples of the weft flying method in an air jet loom according to the invention will be shown below, and weaving efficiency and fabric quality will also be compared with comparative examples.

Example 1 A special reed auxiliary nozzle type jet loom was used as the loom, the loom rotation speed was 60 Or, p, m, and the main nozzle injection timing (crank angle) was selected to be 95 to 240 degrees, and the Kiepra rayon yarn shown in Table 811 was produced. Crank angle ft 60, 65, when fixing the taffeta fabric when the bottle comes off.
The weaving conditions in Table 1 and other weaving conditions are as follows.

○ Auxiliary nozzle injection condition 0 Set air pressure Regular pressure: 0.25 to 0.30 kg/erI-G Main nozzle injection air pressure 2.5 ky/cyl 11GI
I41 initial nozzle injection air pressure 3.5kg/cai-G
Weaving results by changing the crank angle when the fixed bin comes off! It is shown in Table 2. The weaving efficiency in the table is expressed as the number of stoppages due to defective weft flying (times/unit/day), and the fabric quality is expressed as the number of weft defects (items/11 pieces) Example 2 Cupra Rayon of the standard of Example 1 When weaving a thread-based taffeta fabric using the same loom as in Example 1, the crank angle at the timing of the fixing pin coming off was set to 55,6 under the following weaving conditions.
0.7 (1,85,87 degrees, 90 degrees, 100 degrees, 105 degrees) and M weave.

B Loom rotation speed 90Or, p,
mO auxiliary nozzle injection conditions・Set air pressure Regular pressure: 0.35 to 0.40 kF/-・G main nozzle injection air pressure 3.5kf/-・G Su7 sozzle injection air pressure 5.0kf/i@G fixing pin removal timing The results obtained by changing the crank angle are shown in Table 3.

As shown in the above examples, if weaving is carried out using the flying method applied to the air jet loom according to the present invention, weaving efficiency is improved compared to when the conventional flying method is used. [Effects of the Invention] Since the flying method in the air jet loom according to the present invention is configured as described above, this method is adopted. As a result, the weft threads do not come into contact with the fixing pins, causing the single threads to come apart, and there is no variation in the flight distance of the weft threads, which reduces the occurrence of mispicks. As a result, the quality of the resulting fabric is improved, and the efficiency of the parent weaving can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory view of the main parts of an air jet loom having a fixed drum type weft storage drum used when implementing the weft flying method in an air jet loom according to the present invention. l...Weft, 2...Fixed drum, 5.
...Fixing pin, 9...Main nozzle. Patent agent Asahi Kasei Industries Co., Ltd. Patent application agent

Claims (1)

[Claims] 1. In an air-jet loom having a weft storage drum, the weft stored in the weft storage drum is unwound by pressurized air jetted from a main nozzle and is made to fly into an opening formed by a plurality of warp yarns. In this case, the release timing of the unraveling prevention fixing pin on the weft storage drum is set to be 5° to 30° earlier than the timing at which the injection of pressurized air is started from the main nozzle based on the crank angle of the air jet loom. Weft flying method in jet loom.