JPH0424454B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a drum-type weft storage device in which a storage drum is held stationary, and the weft is wound and stored around the surface of the storage drum by a winding guide that rotates around the surface of the storage drum. The present invention relates to a method for weaving using a fragmentary loom equipped with a stationary drum type weft storage device (hereinafter referred to as a static drum type weft storage device) while preventing the stored weft from becoming loose.

In a fragment loom such as a water jet loom or an air jet loom equipped with a stationary drum type weft storage device, a bearing 3 is attached to a frame 1 via a bracket 2, as shown in FIG.
The storage drum 5 is relatively rotatably supported on the front end of the rotating shaft 4 which is supported by and rotates, and is held stationary by a magnet 6. The weft yarn 8 is pulled out from a yarn feeder (not shown) by a guide 7 and is continuously wound around the storage drum 5 and stored.
The first locking body 11 and the second locking body 12, which respectively protrude and retract at predetermined timing into the holes 9 and 10 provided around the storage drum 5, are used to extend the length of one weft insertion until weft insertion. At the time of weft insertion, the second locking body 12 is operated to retract and unwind the stored weft 8, which passes through the guide 13 and the weft gripper 14 to the weft insertion nozzle 1.
Insert the weft by step 5. A ballooning regulating body 19 is supported by the bracket 2 via a support 20 and surrounds the storage drum 5.

By the way, in the above stationary drum type weft storage device, at the end of weft insertion, as the length of the weft 8 on the storage drum 5 decreases, the first locking body 11 and the guide 13 become in a straight line state. Due to inertia, the weft yarn 8 that is supposed to be overruns in the unwinding direction on the storage drum 5, and the overrun portion of the weft yarn 8 becomes slack between the storage drum 5 and the guide 13, and the tension of the weft yarn 8 is lost. , first locking body 11
As a result of the weft yarn 8 wound closer to the tapered portion being pulled back by the pull-out resistance on the yarn supplying body side, the measured yarn length may become shorter, which may cause problems in weaving. As a countermeasure against this, as shown in FIG.
The storage drum 5 is bent by a guide 18 at the tip of a lever 17 attached to a swing shaft 16 provided next to the guide 13 after weft insertion is completed.
It is conceivable to prevent the weft yarn 8 from becoming loose on the storage drum 5 by applying a tension that pulls out the weft yarn 8 from the storage drum 5. However, when applying tension by mechanically bending the weft yarn 8, it is difficult to adjust the additional tension, and a breakage phenomenon occurs when the tension is applied beyond the allowable strength of the weft yarn. Moreover, this allowable strength differs depending on the weft type, so several trials are required to find the appropriate amount of bending and bending strength.
Moreover, even if this is done, it is difficult to grasp the truly appropriate applied tension.

As described above, in the stationary drum type weft storage device, the locking bodies 11 and 1 are
In order to intermittently lock the weft yarn 8 by protruding and retracting the weft yarn 8, these locking bodies 11 and 12 themselves play almost the same role as the weft gripping device, and originally the weft yarn can be measured even without a weft gripping device. It should be possible to measure the length, store it, and weave it, but in reality, the weft threads become slack due to overrun, making it impossible to measure the length completely.
In particular, weaving of filament yarns without fuzz or yarns that are prone to twisting, such as strongly twisted yarns, is difficult even if a weft gripper and/or lever for bending the weft yarns is simply provided.

In view of the above-mentioned circumstances, the inventors of the present invention have conducted intensive research and have discovered that the behavior of weft overrun occurrence varies greatly depending on the timing of the operation of the weft gripper, and has arrived at the present invention.

That is, the present invention provides a fragment equipped with a stationary drum type weft storage device in which a storage drum is held stationary, and the weft is wound and stored around the surface of the storage drum by a winding guide that rotates around the surface of the storage drum. When weaving with a loom, a weft gripper provided between the storage drum and the weft insertion nozzle is opened from weft injection until just before weft cutting, and the weft portion from the weft gripper to the flying edge is left in a free state. This is a weaving method using a fragment loom equipped with a stationary drum type weft storage device, which is characterized by maintaining

As mentioned above, the first
The weft yarn 8 stored between the locking body 11 and the second locking body 12 is moved by water or air from the weft insertion nozzle 15, which has started spraying just before the retraction operation of the second locking body 12. By the injection, it is unwound and pulled out from the storage drum 5 and flies through the weft opening,
The injection of the weft insertion nozzle 15 is stopped immediately before the end of the weft insertion, and after that, the weft runs due to inertia, and the weft insertion ends when the weft becomes straight from the first stopper 11 to the guide 13. do. Even when the weft gripper 14 is provided, conventionally the weft gripper 14 is closed at the same time as the weft flight is completed, following the timing of the weft gripping of the weft yarn gripper in the case of the pool pipe type weft storage device. It was holding the weft. Therefore, due to inertia when the weft yarn 8 is unwound from the storage drum 5, overrun occurs in the weft yarn 8, causing slack.

In contrast, in the method of the present invention, the weft gripper 14 is not closed even after the weft has finished flying, but is kept open until just before the reed moves forward and the weft is cut. As a result, the weft portion from the weft gripper 14 to the flying end is maintained in a free state from the time of weft injection until just before weft cutting. Therefore, even if an overrun occurs due to inertia when the weft yarn 8 is unwound from the storage drum 5 after the weft yarn flight is completed, the weft yarn 8 is
Tension is applied in the direction from the storage drum 5 toward the weft insertion nozzle 15 and the weft is pulled out, and no sagging occurs. Even if the timing of weft gripping by the weft gripper 14 is delayed in this way,
Due to the braking action of the locking body, the overall tension of the weft yarn from the locking body to the ear on the opposite side of the weft insertion is skillfully balanced, and there is no effect on the state of interweaving with the warp yarns. The longer the weft thread gripper 14 is opened, the more effective it is in applying tension, but if it is left open when cutting the weft thread, the repulsive force at the time of cutting the weft thread will create an effect that promotes overrun. and it is not desirable,
It must be closed at the time of weft cutting.
In addition, by selecting the closing timing of the weft thread gripper 14 and changing the opening section according to the degree of slackness of the weft thread 8, it is possible to select the section where tension is applied due to the forward movement of the reed, thereby achieving optimal length measurement and weft thread flight. conditions can be obtained. Further, by using the method of the present invention in conjunction with a device that bends the weft to apply tension, such as the swinging lever 17 shown in FIG. 1, it is possible to more effectively prevent the weft from loosening. The weft gripper 14 normally opens and closes in conjunction with a crankshaft using a cam system, and the timing can be easily adjusted.

As described above, when weaving using a fragmentary loom equipped with a stationary drum type weft storage device, the present invention provides the following advantages:
The feature is that the weft gripper installed between the storage drum and the weft insertion nozzle is opened from the time the weft is jetted until just before the weft is cut, so that even after the weft has completed flying, the weft is Since it is maintained in a free state, even if the weft yarn overruns the storage drum after the weft yarn has finished flying, it is possible to apply an appropriate amount of tension without causing any slack, and the length of the weft yarn can be measured very smoothly. It can be stored and weaving can be carried out efficiently and smoothly.

[Brief explanation of drawings]

FIG. 1 is a simplified front view of the main parts of a fragmentary loom equipped with a stationary drum type weft storage device. 5...Storage drum, 7...Wrapping guide, 8...
Weft, 11...first locking body, 12...second locking body, 14...weft gripper, 15...weft insertion nozzle.

Claims (1)

[Claims] 1. Weaving is carried out by a fragment loom equipped with a stationary drum type weft storage device that holds a storage drum stationary and stores the weft yarn by winding it around the surface of the storage drum using a winding guide that rotates around the surface of the storage drum. At this time, the weft thread gripper provided between the storage drum and the weft insertion nozzle is opened from the time of weft injection until immediately before weft cutting, and the weft thread portion from the weft thread gripper to the flying end is maintained in a free state. A weaving method using a fragment loom equipped with a static drum-type weft storage device.