JPH0598539A - Control device of weft inserting in jet loom - Google Patents

Abstract

PURPOSE:To obtain the subject weft inserting control device preventing end breakage in completion of weft inserting by operating a braking means laid between a storage device of measuring weft length and a main nozzle for weft inserting based on an amount of weft pulled out from the storage device of measuring weft length. CONSTITUTION:Weft Y wound and stored on a yarn winding face 1b is drawn out in a state released from a meshing action of a weft engaging pin 2a driven by an electromagnetic solenoid 2, the weft Y is discovered by a weft release detector 3 and the detected signal is sent to a control circuit 4. When a given amount of the weft Y is pulled out, an electromagnetic solenoid 13 is excited, a braking wire 9 rotated from a solid line position to a chain line position and the yarn Y passing through a yarn guide inner cylinder 5a and yarn guide rings 6 and 7 is bent. The weft Y is braked by the bent shape and flying speed of the weft Y is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a weft insertion control device in a jet loom.

[0002]

2. Description of the Related Art At the end of flight of a weft in a jet loom, the weft is prevented from being pulled out from the weft measuring and storing device. The weft is prevented from being pulled out by engagement between a winding surface and a weft locking pin. Since such a weft pull-out preventing action suddenly stops the flight of the high-speed flying weft and raises the tension, the weft may be cut.

Japanese Unexamined Patent Publication No. 56-93659 discloses a device for preventing weft cutting when the weft drawing is blocked. In this conventional device, a braking shoe is arranged near the thread winding surface, and the braking shoe contacts the thread winding surface in synchronization with the rotation of the loom main shaft. As a result, braking is applied to the weft thread that is pulled out from the thread winding surface,
The weft drawing speed, that is, the weft flying speed is reduced. The timing of applying the braking is performed shortly before the weft withdrawal is prevented, and a sudden increase in the weft tension when the withdrawal is prevented is suppressed.

[0004]

However, the method of synchronizing the timing of braking with the rotation of the loom main shaft has the following drawbacks. Even in the case of the same type of weft, the flying speed varies with each weft insertion, and the timing at which the weft locking pin prevents the weft from being pulled out varies with each weft insertion. If the winding speed on the winding surface is unwound without being restrained, if the flying speed varies, the unwinding speed of the winding thread that slides out on the winding surface will also vary, and the winding There is a risk that it will escape from the braking action of the braking shoe that contacts the mounting surface. To avoid this, as disclosed in the embodiment of the conventional device, the winding yarn may be constrained and guided by the weft-locking pin that moves in the weft-pulling-out direction. Is quite complicated.

An object of the present invention is to provide a device capable of appropriately performing braking when weft pulling out is prevented without requiring such operation of the weft retaining pin.

[0006]

Therefore, according to the present invention,
Weft braking means for braking the weft between the weft measurement storage device and the main weft insertion nozzle, weft pull-out amount detection means for detecting the weft pull-out amount from the weft measurement storage device, and weft pull-out amount A weft-insertion control device is provided which includes braking timing control means for controlling the operation of the weft braking means so as to suppress the weft flying speed at the end of weft drawing based on the weft drawing amount detection information from the detection means. ..

[0007]

When the detection information obtained from the weft pull-out amount detecting means indicates that a predetermined amount of weft has been pulled out, the braking timing control means actuates the weft braking means. By this operation, the weft is braked, and the blocking shock at the time of blocking the weft withdrawal is alleviated. Since the braking timing is performed based on the detection of a predetermined weft withdrawal amount, in other words, the remaining amount of withdrawal, the timing at which braking is performed by the weft braking means is substantially constant when the weft withdrawal is blocked, and the weft is braked by the weft braking means. There is no escape from action.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment embodying the present invention will now be described with reference to FIGS.
It will be described with reference to FIG. Reference numeral 1 denotes a winding type weft measuring and storing device, in which the weft Y is wound and stored on the yarn winding surface 1b by the rotation of the yarn winding tube 1a. The weft Y, which is wound and stored on the winding surface 1b, is released from the locking action of the weft locking pin 2a driven by the electromagnetic solenoid 2 and the main weft insertion nozzle (not shown).
It is pulled out by the injection action of. The straight line E in FIG. 3 represents the amount of weft Y drawn out, and the machine base rotation accuracy T ₀ represents the weft insertion start timing. The weft thread locking pin 2a is attached to the thread winding surface 1
Engagement with b prevents the weft from being pulled out. The machine rotation accuracy Tw in FIG. 3 represents the pull-out prevention timing.
In this embodiment, the weaving width is 3 windings (length L).

A reflective photoelectric sensor type weft unwinding detector 3 is installed near the yarn winding surface 1b. The weft unwinding detector 3 detects the unwound yarn pulled out from the yarn winding surface 1b, and this detection signal is sent to the control circuit 4.

A cone-shaped ballooning suppressing cover 5 is arranged in front of the weft measuring and storing device 1 to suppress ballooning of the weft Y when it is pulled out from the yarn winding surface 1b and unwound.

The thread guide cylinder 5a of the ballooning suppression cover 5
A pair of yarn guide rings 6 and 7 are arranged in series in front of the. A support shaft 8 is rotatably arranged immediately below the thread guide cylinder 5a and the thread guide ring 6, and a braking wire 9 is fixed to the tip of the support shaft 8. The upper portion of the braking wire 9 is bent and inverted, and the yarn guide ring 6 is provided in the turning region of the bent portion around the support shaft 8.

The support shaft 8 is urged to rotate leftward in FIG. 2 by a torsion spring 10. Position regulating pieces 11 and 12 are arranged above and below the support shaft 8, and the spring action of the torsion spring 10 is received via a braking wire 9. That is, the position regulating pieces 11 and 12 regulate the left turning position of the braking wire 9.

The lower portion of the braking wire 9 is connected to the drive pin 13a of the electromagnetic solenoid 13. When the electromagnetic solenoid 13 is excited, the braking wire 9 is pivotally arranged at the position indicated by the chain line in FIG. Excitation / demagnetization of the electromagnetic solenoid 13 is performed by a command from the control circuit 4.

When the winding yarn on the yarn winding surface 1b is released from the locking action of the weft yarn locking pin 2a and is unwound, the unwound yarn unwinding detector 3 detects the unwound yarn unwinding detector 3. When the weft unwinding detector 3 detects the weft three times, the control circuit 4 excites the electromagnetic solenoid 13 after a predetermined time t ₁ from the three times detection of the weft as shown by the curve C in FIG. Degauss after time t ₂ . The braking wire 9 is rotated from the solid line position in FIG. 2 to the chain line position by the excitation of the electromagnetic solenoid 13, and the weft yarn Y passing through the yarn guide cylinder 5a and the yarn guide rings 6 and 7 is bent by the rotating arrangement of the braking wire 9. To be made. With this bent shape, the weft Y
Is braked, and the flying speed of the weft Y is reduced.

The weft withdrawal amount when the weft unwinding detector 3 detects the weft yarn three times is two windings (2L / 3), and when the weft withdrawal amount is three windings (L), that is, When the weft locking pin 2a prevents the weft Y from being pulled out, the weft Y is braked by the braking wire 9.
Therefore, the weft Y is not cut by the shock when the pulling out is blocked.

The timing of braking the weft yarn Y can be changed by selecting a time t _1, the time t ₁ is set as appropriate from the prediction of the time elapsed from the entire 2L / 3 is weft withdrawal-amount until a total volume of L To be done. There is some variation in the flying speed of the weft Y, but according to the method of determining the timing of braking based on the detection result of the weft withdrawal amount 2L / 3 for each weft insertion, when the weft withdrawal of 2L / 3 is completed The variation of the flying speed of the weft Y after that is significantly reduced. Therefore, the total weft pull-out amount is 2L.
The prediction of the elapsed time from / 3 to the total amount L is the prediction of the elapsed time from the weft withdrawal amount of 0 to the total amount L. This is much more accurate than that of (corresponding), and the deviation between the braking timing and the weft pull-out prevention timing indicated by the curve C in FIG.

The present invention is of course not limited to the above-mentioned embodiment, and for example, as shown in FIG. 4, a braking nozzle 15 is mounted in a pipe 14 for supporting the yarn guide rings 6 and 7, and the braking nozzle 15 is used. The weft yarn Y may be bent to apply braking. The electromagnetic on-off valve 16 that controls the supply of pressure air to the braking nozzle 15 is controlled by the control circuit 4 to be demagnetized.

Further, as the weft yarn withdrawal amount detector, a detector for detecting the flying position of the weft yarn flying in the warp yarn opening may be employed.

[0019]

As described above in detail, according to the present invention, the timing of braking the weft between the weft measuring and storing device and the main weft inserting nozzle is determined based on the detection result of the weft withdrawal amount. As a result, the timing at which the weft braking means applies braking is substantially constant after the weft insertion is completed, and the braking that can prevent the yarn breakage is accurately applied to the weft.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment embodying the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a graph showing a weft withdrawal amount and a braking timing.

FIG. 4 is a vertical cross-sectional view showing another example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Weft length measuring storage device, 3 ... Weft unwinding detector which serves as weft pull-out amount detecting means, 4 ... Control circuit which serves as braking timing control means, 9 ... Braking wire which constitutes weft braking means,
13 ... Electromagnetic solenoid forming weft braking means, Y ... weft

Claims (1)

[Claims] Claim: What is claimed is: 1. In a jet loom in which a stored weft in a winding type weft measuring and storing device is injected by a jetting action of a weft inserting main nozzle, a weft between a weft measuring and storing device and a weft inserting main nozzle. At the end of weft pull-out based on the weft pull-out amount detection means for detecting the weft pull-out amount from the weft measuring and storing device, and the weft pull-out amount detection information from the weft pull-out amount detection means. A weft insertion control device in a jet loom, comprising: a braking timing control means for controlling the operation of the weft braking means so as to suppress the weft flying speed.