JPH0572986U - Weft insertion device for fluid jet loom - Google Patents

Abstract

(57) [Summary] [Purpose] By actively restraining the weft yarn in a flying state without slipping, and decelerating the weft yarn to a prescribed speed,
It is to solve the conventional drawbacks. [Structure] During weft insertion, the weft thread is sandwiched by deceleration rollers that rotate at a peripheral speed almost equal to the thread speed at a predetermined time of the end of weft insertion before the weft thread is restrained, and the thread speed is reduced by the roller deceleration rotation. The limit is ensured and the speed is kept at a predetermined level.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weft inserting device for a fluid jet loom, and more particularly to a means for reducing the speed of a weft yarn in flight at the end of weft insertion.

[0002]

[Prior Art]

 Japanese Utility Model Publication No. 59-25896, Japanese Utility Model Publication No. 3-45966, Japanese Utility Model Publication No. 3-18527 discloses a braking device for the purpose of reducing the impact when the weft thread is restrained at the end of weft insertion. Is disclosed. In these devices, the construction of the braking device does not completely restrain the weft thread, but is so-called negative braking in which the movement is allowed by sliding, so the thread speed at the time when the weft thread is finally restrained. It is affected by fluctuations in yarn speed before and after the threading. Therefore, it is not possible to uniformly suppress the effect of weft binding. In other words, if the yarn speed before braking fluctuates and becomes large, the yarn speed when the weft yarn is restrained also becomes relatively large, and yarn breakage may occur. Also, during braking, the weft thread slides on the braking member or is exposed to a high-speed air flow, so the weft thread is easily damaged.

Further, Japanese Patent Laid-Open No. 59-82447 discloses a yarn brake for the purpose of alleviating the impact when weft is restrained, and further, in order to make the arrival time of the weft insertion final point constant, It is disclosed that the operation timing and / or the braking force of the yarn is changed and controlled according to the yarn speed.

Even in the above technique, since the structure of the brake is negative, it is difficult to uniformly suppress the impact when the weft yarn is restrained even by automatic control. However, when the yarn speed is high, by applying a large amount of braking, the yarn speed at the time of weft yarn binding can be made smaller than that at a low yarn speed, so the impact at the time of weft yarn locking can be made smaller than the above technique. .. Further, since the weft thread slides on the braking member during braking, the weft thread is easily damaged as in the above technique.

As described above, the conventional one has a problem that the weft thread is not easily controlled because the braking force is negatively exerted by sliding contact with the weft thread, and the weft thread is easily damaged. ..

[0006]

[The purpose of the device]

 Therefore, an object of the present invention is to solve the conventional drawbacks by positively restraining the weft yarn in a flying state without slipping and decelerating the weft yarn to a predetermined yarn speed.

[0007]

[Means for solving the problem]

 Based on the above-mentioned object, the present invention, during weft insertion, at a predetermined braking time at the end of weft insertion before restraining the weft thread, the weft thread is sandwiched by rollers that decelerate and the thread speed is controlled by the peripheral speed of the roller. We are sure to limit it and keep it at a predetermined speed.

[0008]

【Example】

 FIG. 1 shows the construction of a weft inserting device 1 of a fluid jet loom according to the present invention. The weft yarn 2 is fed from the yarn feeding package 3, and is measured by, for example, a fixed drum type length measuring storage device 4 for a length required for one pick weft insertion, for example, 4 rolls, and until the weft insertion timing. It is locked and retained by a locking pin 7 as a thread locking member.

That is, the rotating yarn guide 5 rotates the outer circumference of the fixed drum 6 to wind the weft thread 2 locked by the locking pin 7 around the outer circumference of the fixed drum 6, and measures the length. It is stored up to the timing of horizontal insertion. When the locking pin 7 is retracted by the operation device 8 such as an electromagnetic solenoid at the weft insertion timing, the weft yarn 2 in the length-measuring state is unwound around the outer periphery of the fixed drum 6, and the liquid ejected from the main nozzle 9 is also discharged. The warp thread 10 is picked up in the opening 11 of the warp thread 10.

The weft insertion device 1 of the present invention includes a braking mechanism 12 as a characteristic part. The braking mechanism 12 is located between the length measuring and storage device 4 and the main nozzle 9, and is a roller 17 on the rotation side driven by a motor 16 capable of speed control, and a driven roller that comes into contact with and separates from the roller 17 and sandwiches the weft thread 2 therebetween. It is assembled by the side roller 18 and a lever 19 which supports the roller 18 in a swingable state. The lever 19 has one portion rotatably supporting the roller 18, and the other portion rotatably supported at a fixed position by a fulcrum shaft 20. Further, the lever 19 is fixed to a loom frame or the like. It is connected to a plunger 21 of the formula, and is supported so as to come into contact with and separate from the roller 17 at a position where the weft 2 is sandwiched.

Further, in order to detect the weft insertion length of the weft yarn 2, a sensor 13 is provided in the passage of the weft yarn 2. In the case of this embodiment, the sensor 13 is constituted by an unwinding sensor which detects the length of the weft thread 2 from the unwinding number of the weft thread 2 at the outer peripheral position of the fixed drum 6.

Then, the control device 14 receives the angle signal from the shaft encoder 23 of the main shaft 22 of the loom and the yarn detection signal from the sensor 13 and controls the operating device 8 as well as the plunger 21 and the rotation controller 15. To do. The rotation controller 15 stores the peripheral speed of the roller 17 on the rotation side relative to the rotation angle of the main shaft 22 in advance as a speed pattern by a built-in program, and decelerates based on the rotation angle signal from the shaft encoder 23. Is generated to control the rotation speed of the motor 16, that is, the peripheral speed of the roller 17.

FIG. 2 shows the unwinding / locking operation of the locking pin 7 as a thread locking member, the operation of the plunger 21, the jetting operation of the main nozzle 9, the flight distance of the weft thread 2 and the thread tension of the weft thread 2. The change is shown on the rotation angle (time axis). During weaving, the length measuring and storage device 4 measures the length of the four weft yarns 2 on the fixed drum 6 as a length required for one pick weft insertion, and stores it until the weft insertion timing. At the rotation angle corresponding to the weft insertion start timing during the weft insertion period, the control device 14 drives the operating device 8 and retracts the locking pin 7 to unwind the weft yarn 2 on the outer peripheral surface of the fixed drum 6. After unwinding and unwinding three turns, the locking pin 7 is advanced to lock the weft thread 2 in the unwound state on the fixed drum 6.

Here, the main nozzle 9 injects the fluid at the unraveling period of the locking pin 7 from the unwinding time, that is, the weft insertion start timing to the unwinding time of four rolls, that is, the weft insertion end timing. The weft thread 2 in the state is inserted into the opening 11. As a result, the weft yarn 2 is inserted into the opening 11 of the warp yarn 10 from the weft insertion start timing in a free flying state together with the fluid at a predetermined speed and under a predetermined yarn tension.

During this time, the rotation controller 15 detects the end of weft insertion before the weft thread 2 is locked by the locking pin 7, for example, from the rotation angle θ1 to the rotation angle θ4 by the shaft encoder 24, and the motor 16 is driven. After starting, the motor 16 is rotated based on the deceleration speed characteristic at least during the braking period from the rotation angle θ2 to the rotation angle θ3, and the rotation speed of the roller 17 on the rotation side causes the peripheral speed suitable for reducing the flying speed of the weft thread 2. Giving a rotation.

On the other hand, the control device 14 detects the rotation angle of the main shaft 22 by the shaft encoder 23, and before the weft thread 2 is locked by the locking pin 7, at the end of weft insertion, that is, from the rotation angle θ2 to the rotation angle θ3. In the meantime, the plunger 21 is driven to move the roller 18 at the standby position to a position in contact with the roller 17 on the rotation side, and the weft yarn 2 is sandwiched between the pair of rollers 17, 18.

At the end of weft insertion, the pair of rollers 17 and 18 are sandwiched at a peripheral speed substantially equal to the flying speed of the weft thread 2 at that time, and then gradually decelerated based on the deceleration characteristic. When the weft yarn 2 is sandwiched between the pair of rollers 17 and 18 in a non-slip state, the weft yarn 2 is limited to a speed corresponding to the circumferential speed of the rollers. For this reason, the yarn tension temporarily increases at the position of the rotation angle θ2, but the yarn tension is not so large as to cause a yarn breakage and is suppressed within a small fluctuation range.

In this way, the weft yarn 2 is weaved in a free-flying state from the weft insertion start timing, but at the end of weft insertion, that is, the braking period from the rotation angle θ2 to the rotation angle θ3, It is sandwiched between a pair of rollers 17 and 18, and flies by being constrained by its peripheral speed to fly, becoming a so-called restrained flight state, reducing the flying speed, and eventually after the end of the braking period, the locking pin 7 reaches the point of locking. During the braking period before the locking pin 7 locks the weft thread 2, the weft thread 2 is restrained by the pair of rollers 17 and 18 and is kept at a low speed. Even when locked, the increase in thread tension at that time can be suppressed to a low level as compared with the conventional one.

That is, in the conventional one, as shown by the dotted line in FIG. 2, when the locking pin 7 locks the weft yarn 2 in the free-flying state, the speed of the weft yarn 2 reaches the maximum value, At that point, when the locking pin 7 locks the weft thread 2, the thread tension at that time rises sharply and reaches a high value, as shown by the dotted line. This can cause yarn breakage and wefting defects.

However, in the present invention, before the weft thread 2 is locked by the locking pin 7, the pair of rollers 17 and 18 sandwich the weft thread 2 in a non-slip state to prevent the free flight from the restrained flight. In this state, the weft thread 2 is restricted to a low speed by matching it with the peripheral speeds of the rollers 17 and 18, so that the thread tension of the weft thread 2 at the time of locking by the locking pin 7 does not become higher than that of the conventional one, but is low. It can be suppressed. As a result, breakage of the weft thread 2 can be prevented, and the occurrence of weft insertion failure due to fluctuations in thread tension can be suppressed to a low level.

Even when the locking pin 7 locks the weft thread 2, if the pair of rollers 17 and 18 hold the weft thread 2 in between, a yarn breakage occurs between them, so that the pair of rollers 17, The part 18 is separated before the weft thread 2 is locked by the locking pin 7 to leave the weft thread 2 in a free state.

In the above embodiment, the operation timing of the braking mechanism 12 is controlled by the rotation angle of the main shaft 22 detected by the shaft encoder 23, but instead of this, the operation timing is controlled based on the yarn detection signal from the sensor 13. You may do so. If an unwinding sensor is used as the sensor 13, for example, the plunger 21 can be actuated when the weft yarn is unwound and unwound by 2.5 turns, and stopped when the weft yarn is unwound and unwound by three turns. Instead of detecting the weft insertion length from the unwinding number, a sensor 13 may be provided along the weft insertion path as shown by an imaginary line in FIG. In this way, if the operation timing of the braking mechanism 12 is controlled based on the signal from the sensor 13, it is possible to follow the fluctuation of the yarn speed at the time of weft insertion. You can brake. In addition, the operation timing of the braking mechanism 12 may be controlled based on the elapsed time after the start of loading.

Also, the operation timing of the motor 16 may be controlled by the yarn detection signal from the sensor 13 or the elapsed time after the start of weft insertion, instead of controlling by the rotation angle as in the above.

[0024]

[Other Examples]

 FIG. 3 shows another embodiment in which the weft thread 2 is sandwiched by a pair of rollers 17 and 18. The pair of rollers 17 and 18 rotate in the feeding direction of the weft yarn 2 at a predetermined speed in a state where they are always in contact with each other. On the other hand, the weft yarn 2 is passed through the yarn guide 24 and can be moved from the standby position to the contact position of the pair of rollers 17 and 18 by the rotary actuator 25 of the yarn guide 24. When the weft yarn 2 is in the free flying state, the yarn guide 24 is in the standby position where the weft yarn 2 is separated from the contact position of the pair of rollers 17 and 18, but when the weft yarn 2 is in the restrained flying state, the weft yarn 2 is Is made to enter the contact position of the pair of rollers 17 and 18, and the flying speed thereof is restricted by the peripheral speed of the rollers 17 and 18, and the speed is reduced to a predetermined speed.

In order to make the arrival time at the final position of the weft insertion constant, the yarn speed during weft insertion is detected by the unwind sensor, the sensor 13 provided in the weft insertion path, etc., and in response to the slow speed, The braking timing (on and / or off) can also be automatically controlled.

The peripheral speed of the roller 17 is preset in consideration of the yarn speed at the time of weft insertion, that is, the yarn speed in the free-flying state. The yarn speed of the weft yarn is detected by a yarn speed sensor, an unwinding sensor, a sensor provided in the weft insertion path, and the impact when the weft yarn 2 is locked by the locking pin 7 according to the detected yarn speed. The peripheral speed may be automatically changed and controlled so as to keep constant.

Further, in the above embodiment, the length measuring and storing device 4 is configured as a drum type. However, the length measuring and storing device 4 is a device that is a combination of a length measuring roller and an air pool for storing. May be In the air pool type, the weft thread 2 is free to fly in the initial stage of weft insertion, but after that, the weft thread 2 is in a restricted flight state at the peripheral speed of the length measuring roller, and is finally engaged by a clamper as a locking member. Be stopped. Even with this type of length measurement storage device, the yarn speed is rapidly reduced when transitioning from free flight to restrained flight, causing yarn breakage. Therefore, the device of the present invention is also effective for such a length measuring and storing device.

[0028]

[Effect of the device]

 In the present invention, since the weft yarn is braked by being restrained by the roller, the yarn speed during braking is not affected by the yarn speed before braking, and thus the final weft yarn is not locked by the locking pin. The impact at the time of being restrained can be suppressed to a low level, and thread breakage can be reliably prevented. Since the weft thread is braked by being restrained by the roller, there is no relative movement or sliding between the roller as a braking member and the weft thread. And thread breakage can be kept low.

[Brief description of drawings]

FIG. 1 is a block diagram of a weft insertion device of a fluid jet loom.

FIG. 2 is a timing chart during a weft insertion operation.

FIG. 3 is a side view of a main part of another embodiment.

[Explanation of symbols]

 1 Weft insertion device of a fluid jet loom 2 Weft yarn 4 Length measuring storage device 9 Main nozzle 11 Opening 12 Braking mechanism 13 Sensor 14 Controller 15 Rotation controller 16 Motor 17 Roller 18 Roller 21 Plunger

Claims (1)

[Scope of utility model registration request] 1. A length measuring storage device stores a weft yarn while measuring the length of the weft yarn, and the weft yarn can be put in the weft yarn by a locking / unwinding movement of a weft yarn locking member. In a fluid injection type loom in which a weft is inserted into a shed by a nozzle, a deceleration roller that rotates by inserting a weft thread between a length measuring storage device and a weft insertion nozzle, a motor that drives the deceleration roller, and a weft insertion A control device for gripping the weft thread by the deceleration roller at a predetermined braking time at the end of weft insertion before the inner weft thread is locked by the thread locking member, and the rotation speed of the motor according to the flying characteristics of the weft thread. And a rotation controller for rotating the roller in the feed-out direction at a peripheral speed lower than the yarn speed at the braking timing by controlling the horizontal axis of the fluid-jet loom. Putting device.