JPS60151343A - Method and apparatus for limiting wefting length of drum type weft yarn storage apparatus - 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 Technical Field of the Invention The present invention relates to a drum-type weft yarn storage device, and more particularly to a method and device for accurately regulating the weft insertion length of the weft yarn.

Technical '/V' Scenery In this type of drum-type weft yarn storage device, the length measurement and storage of the weft yarn are performed using the outer peripheral surface of the storage drum.

Therefore, the weft insertion length of the weft yarn is regulated by the outer peripheral length of the drum and the number of unwindings thereof. For this reason, the number of unwindings must be set accurately during unwinding.

Prior art For example, Japanese Patent Application Publication No. 57-29640 and Japanese Patent Application Publication No. 11"5
The invention of B-174654 shows the provision of a monitoring device or weft thread sensor on the side of the drum. In these conventional techniques, since the number of unwound yarns on the drum cannot be accurately measured, an excess or deficiency of about one turn is likely to occur, resulting in a length measurement error. In particular, such changes in weft length may occur during transient operating conditions of the loom, especially immediately after the start of operation.
noticeable.

Purpose of the Invention Therefore, the purpose of the present invention is to maintain the weft insertion length constant regardless of changes in the type of weft yarn or operating conditions of the loom, and to prevent the occurrence of short-bick, long-pink, etc. even in the case of multi-colored weaving. The goal is to prevent this from happening.

SUMMARY OF THE INVENTION Therefore, the present invention detects the tip of the weft thread inserted in the middle of the weft thread, and after a predetermined time from the detection point, moves the thread clamp in the weft thread locking direction to lock the weft thread. . The locking timing of the thread clamp is adjusted every time we weft or at a certain period of weft, thereby accurately regulating the length of weft. Here, the detection position of the weft yarn corresponds to at least one turn of the drum, and the movement of the yarn clamp to the locking position is performed after the start of unwinding of the last turn of the weft yarn.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of the present invention will be specifically described below based on an embodiment shown in the drawings.

The present invention is based on the existence of the drum-type weft yarn storage device 1. This drum type weft yarn storage device 1 includes a winding arm 2, a storage drum 3, and a yarn clamp 4 as main parts. For winding, the arm 2 is rotatably supported by the shaft 5, and internally pulls out the weft yarn 6 from the yarn feeder 7 via the yarn guide 8, and sequentially winds it around the outer peripheral surface of the storage drum 3. go. This storage drum 3 is connected to the shaft 5
The winding is supported in a rotatable state against the winding member, and the winding is stopped by known rotation prevention means during operation.

This locking and unwinding of the weft thread 6 is performed by the thread clamp 4. This thread clamp 4 is attached to the drum 3
It is provided so as to be movable forward and backward in the diametrical direction at a position on the outer circumference thereof, and is driven in the forward and backward directions by an electromagnetic or fluid-driven plunger 9. That is, when the thread clamp 4 is retracted and separated from the circumferential surface of the drum 3, the weft thread 6 is set to the unwound state. Further, when the yarn clamp 4 advances to the drum 30 side, the weft yarn 6 being unwound is locked thereto, so that the unwinding is completed, that is, the weft insertion is completed. During wefting, the unraveled weft yarn 6 passes through the yarn guide 10 and is injected from the wefting nozzle 11 together with a wefting fluid, for example, air.
fly along

Note that the extending path 12 is formed on the front side of the modified reed 13.

Now, the weft insertion length regulating device 14 of the present invention includes an optical weft sensor 15, a controller 16, and a timing sensor 17 in addition to the yarn clamp 4 described above. The weft sensor 15 is installed on the side of the weft track 12, for example, at a distance corresponding to the length of at least one turn of the drum 3 from the end of the fabric on the side where the weft has not been reached, and at a position closer to the weft insertion side. and is connected to the input end of the controller 16. Furthermore, the timing sensor +-17 corresponds to a rotating body 18 that rotates in synchronization with the rotation of the loom.
Detects the rotational phase of and corresponds to the timing of weft insertion.
A signal is sent to the controller 16. Further, the controller 16
Upon receiving the timing signal from the timing sensor 17, an activation signal is sent to the plunger 9, and the thread clamp 4 is activated.
is moved back to the h1-threading state, and then receives a detection signal from the weft thread sensor 15, and after a certain time delay caused by the delay circuit, sends an activation signal to the plunger 9, moves the thread clamp 4 forward, and threads the thread. Weft thread 6 being unwound with clamp 4
The lock is performed.

Functions of the Invention The functions of the drum-type weft yarn storage device 1 and the weft insertion length regulating device 14 will be described below.

As described above, the weft yarn 6 is wound in sequence around the outer peripheral surface of the storage drum 3 by the rotation of the arm 2. When the yarn clamp 4 is in contact with the circumferential surface of the drum 3, the stored weft yarn 6 is locked thereby and is not inserted. However, after that, when the loom reaches the weft rotation angle, the timing sensor 17 detects this and sends the timing signal to the controller 16. At that point, the controller 16 drives the plunger 9 and threads the yarn. Move the clamp 4 by a retreating force of 1iiJL,
Set it to the unwinding position. As a result, the weft thread 6 in the stored state
is in an unrolled state. At this time, the weft insertion nozzle 11 injects pressurized air and inserts the weft yarn 6 toward the thread 12. When the tip of the weft yarn 6 reaches the position of the weft yarn sensor 15, the weft yarn sensor 15 optically detects it and sends a detection signal to the controller 16. Therefore, upon receiving the detection signal, the controller 16 releases the biasing state of the plunger 9 after the start of unwinding of the last turn of the weft yarn after a certain time delay caused by the delay circuit, and thereby releases the biasing state of the plunger 9. The weft yarn 6 is moved in the advancing direction, and the weft thread 6 being unwound is locked at the locking position to be in a clamped state. Therefore 1
The length of the picked weft yarn can be accurately regulated, and the tip of the weft yarn 6 during wefting can accurately reach the weaving prostitute on the opposite yarn feeding side.

Here, the time from when the tip of the weft yarn 6 reaches the position corresponding to the weft yarn sensor 15 until the yarn clamp 4 reaches the clamp position is the time required for the weft yarn 6 to unwind by 1/28 from the drum 3. For example, if the number of unwindings for one pick is 4, the tip of the weft 6 corresponds to the weft sensor 15 when three turns of the weft 6 are completely unwound from the drum 3. Since the yarn clamp 4 is in the clamp position when the weft yarn 6 reaches the position and 3.5 turns have been unwound, the weft yarn 6 is unwound when the weft yarn 6 has been unwound by 4 turns from the drum 3. is stopped immediately, and the weft thread 6 of the specified weft insertion length is passed through exactly 12 times.
He will be taken to the side.

In the above case, in order to place the thread clamp 4 in the clamp position at an appropriate timing, the delay time of the aforementioned delay circuit may be appropriately changed.

Modified Example of the Invention In the above embodiment, the locking and unwinding of the weft thread is controlled by one thread clamp 4, but a plurality of thread clamps 4 are provided for the drum 3. They may lock and unwind the weft thread 6 alternately. In addition, as described in the above embodiment, the weft sensor 15 is installed at a position moved upstream from the weaving end by an amount corresponding to one turn of the weft 6 on the circumferential surface of the drum 3; This position may be further upstream by interposing a time delay element or the like in the controller 16 or the like. In addition, the controller 16 is not limited to the delay circuit as described above, but also sends a signal from the yarn sensor 15 at the weft monitoring position to the controller 16, and compares the signal with a set value in the controller. Using a known circuit for determining the timing of clamp 4, the signal that controls the timing of clamp 4 is
It is also possible to send the data to

Effects of the Invention In the present invention, a device for counting the number of weft threads unwound from the drum circumferential surface is not required, and even when multiple thread clamps are installed, one weft thread monitoring device is not required without changing the external shape of the drum. Accurate mako insertion length can be regulated by the weft thread sensor. In particular, unlike conventional yarn detection means that is provided around the drum, it is only necessary to detect the presence or absence of a single weft yarn on the side of the thread. Compared to sensors that detect the number of wires, it enables accurate detection without malfunction.

[Brief explanation of the drawing]

The figure is a block diagram of the weft length regulating device of the present invention. 1. Drum type weft storage device, 2. Arm for winding,
3. Drum for storage, 4. Yarn clamp, 6. Weft, 9. Plunger, 11. Nozzle for weft insertion.
12...Hi-way, 14...Horizontal insertion length regulating device, 15.
- Weft thread sensor, 16...controller, 17...timing sensor.

Claims (2)

[Claims] (1) In a drum-type weft yarn storage device in which a weft yarn is wound around the outer circumferential surface of a drum, and the weft yarn is locked and unwound by a yarn clamp provided so as to be movable forward and backward relative to the circumferential surface of the drum, it is possible to Detecting the tip of the weft yarn at a position where it enters the weft insertion side by a distance corresponding to the length of at least one turn of the drum from the weaving end on the weft arrival side on the side of , and after this detection, A method for regulating weft insertion length of a drum-type weft yarn storage device, characterized in that the yarn clamp is moved from an unwinding position to a locking position during unwinding for the final 1@. (2) In a drum-type weft yarn storage device in which the weft yarn is wound around the outer circumferential surface of the drum, and the weft yarn is locked and unwound by a yarn clamp provided movably forward and backward relative to the circumferential surface of the drum, A detection signal is generated by detecting the tip of the weft yarn inserted at a position where it enters the weft insertion side by a distance corresponding to the length of one roll of the drum from the weaving end on the side where the weft yarn reaches. a weft yarn sensor that generates a weft thread, a controller that generates a control signal during unwinding of the last winding after the generation of the detection signal, and a controller that receives the control signal from the controller and moves the yarn clamp in the locking direction. A weft insertion length regulating device for a drum-type weft yarn storage device, characterized by comprising a moving plunger.