JPH0680222B2 - Weft cutting device for shuttleless loom - Google Patents

Description

TECHNICAL FIELD The present invention relates to a weft cutting device in a shuttleless loom, and in particular,
When the weft injected from the weft insertion nozzle does not reach the opposite weft insertion side, in order to easily remove this failed weft that does not reach while remaining connected to the yarn supplying side, a defective weft between the weft insertion nozzle and the warp The present invention relates to a weft cutting device configured to prevent the cutting of the weft.

[Conventional technology]

As a conventional device of this type, for example, a device used in an air-jet loom will be described and shown in FIG. 6 (Japanese Utility Model Publication No. 56-17503).

FIG. 6 shows the vicinity of the weft inserting nozzle 1 for injecting the weft yarn W. Reference numeral 2 is a weft cutting device, which includes a weft cutter 3 including a fixed blade 3a and a movable blade 3b, and a blocking device 4. The fixed blade 3a is fixed to the machine frame 6 via the sleeve 5, and the movable blade 3b is rotatably supported by the sleeve 5 via the shaft 7. A spring (not shown) is provided inside the sleeve 5 to constantly urge the movable blade 3b toward the fixed blade 3a. Reference numeral 8 denotes an arm fixed to the shaft 7, which swings in synchronization with the loom, rotates the movable blade 3b, and causes the movable blade 3b to cooperate with the fixed blade 3a to perform scissor cutting motion.

The blocking device 4 is composed of, for example, an air cylinder that expands based on the excitation of the coil 10, and pushes the shaft 7 against the biasing force of the spring during the expansion to separate the movable blade 3b from the fixed blade 3a, and the weft cutter. This is to prevent the scissors-cutting function of 3. Generally, a weft detector is mounted on a fluid jet loom such as air. This uses, for example, an optical sensor, and is attached to the downstream end of the weft flight path,
The presence or absence of weft is detected at the end of the weft insertion period. When the absence of the weft is detected, the coil 10 is excited by a weft-insertion abnormality signal from a control device (not shown), and the excitation is performed based on this signal. The drive motor of the loom is also stopped based on this signal. Incidentally, reference numeral 11 is a guiding means, which reciprocates together with a reed (not shown),
The weft W is brought into the opening of the weft cutter 3.
Reference numeral 12 is a clamping mechanism for holding the weft W based on the weft-insertion abnormal signal on the lateral blade 1a of the weft-insertion nozzle and applying tension to the weft W.

Then, when the weft insertion abnormality signal is issued, the coil 10 is excited and the drive motor of the loom is also stopped. In general, the reed driven by the main shaft cannot be stopped immediately due to inertia, and the faulty weft is already driven into the woven fabric when the main shaft is completely stopped.
3b rotates in synchronization with the loom, but the movable blade 3b is separated from the fixed blade 3a, so that the defective weft is not cut. After that, the main shaft is reversed to open the warp, and
The weft yarn W between the weft insertion nozzle 1 and the warp yarn is pulled in the anti-beating direction by 13 and the weft yarn W is separated from the warp yarn. In this case, since the weft W is clamped by the clamp mechanism 12,
Only the faulty weft W that is driven into the warp is pulled. Then, for example, the weft W is sucked by a suction device (not shown), and the defective weft is discarded.

[Problems to be solved by the invention]

By the way, the conventional weft cutting device 2 has a problem that the weft cutter 3 may be poorly cut and may cause cutting failure in a steady state.

Since the movable blade 3b is moved away from the fixed blade 3a by moving the shaft 7 when weft insertion is abnormal, the movable blade 3b and the fixed blade 3a are aligned when the movable blade 3b returns to its original position. This is because the weft may not be sufficiently sheared and the weft may not be sufficiently sheared. Especially with the recent increase in the speed of the loom. The scissor cutting motion of the weft cutter 3 is, for example, 600,000 or more times a day. Therefore, if the shearing function is impaired, the loom will be stopped more often and the speed cannot be increased.

Therefore, the technical problem of the present invention is to prevent scissors cutting movement of the weft cutter without moving the shaft when weft insertion is abnormal.

[Means for solving problems]

The technical means of the present invention for solving such a problem is that a weft cutter 20 that performs a scissor cutting motion composed of a fixed blade 3a and a movable blade 3b is swung by a cam 27 that rotates in synchronization with a loom. Movable blade drive link system 21, 22 for operating the movable blade 3b
In the weft cutting device provided with the blocking devices 30 and 60 that block the scissors cutting motion based on the weft insertion abnormal signal, the blocking devices 30 and 60 define the reciprocating movement region of the link system from the cam follower to the movable blade. Has a rotation axis in a plane including and
Locking parts 31a, 61a that can advance into the swinging area of the link system
And a driving unit 32,63 for advancing the blocking piece into the reciprocating region in response to a weft insertion abnormality signal.
And the engaging portion 31a, 61a of the link system has an engaging portion orthogonal to the reciprocating direction, the locking portion when the advance into the swing region of the link system It is a weft cutting device in a shuttleless loom including an abutting portion that is parallel to the engaging portion.

[Action]

According to this means, when the weft insertion abnormality occurs, the blocking piece advances into the swing region of the weft cutter by the drive unit, the swing of the weft cutter is stopped, and the scissors cutting function is blocked. At this time, the biasing force of the link system does not exert a component force on the blocking piece that is displaced in the latitudinal direction, and the blocking piece does not escape, so locking can be ensured, and the blocking piece has its rotation. Since a force in the direction perpendicular to the axis works, it is not necessary to consider the moment or the like.

〔Example〕

Hereinafter, a weft cutting device according to an embodiment of the present invention will be described with reference to the accompanying drawings.

1 and 2 show a weft cutting device C1 according to the first embodiment.

In the figure, reference numeral 20 is a weft cutter, which comprises a fixed blade 20a and a movable blade 20b. The fixed blade 20a is fixed to the bracket 19 attached to the frame of the loom, while the movable blade 20b is fixed.
Is swingably supported by a bracket 19 via a rotating shaft 21. Reference numeral 22 denotes an arm of the weft cutter 20, which is fixed to the rotary shaft 21 at a fork portion 23 thereof. This arm 22
Is constantly urged in the cutting direction R by the spring 25 at the other end. A roller 26 as a cam follower is attached to the other end of the arm 22. A cam 27 that rotates in synchronization with the loom is engaged with the roller 26. Cam 27
A high portion 27a that sets the arm 22 at a position where the fixed blade 20a and the movable blade 20b open the opening, and a low portion 27b that sets the arm 2 at a position that closes the opening at a predetermined time after the end of beating are formed. It becomes. Then, in the arm 22, the roller 26 is cam 27
While rolling from the high portion 27a to the low portion 27b, the spring 27 is swung against the urging force of the spring 25, and the bottom portion 27a
While rolling from b to the high portion 27a, the fixed blade 20a and the movable blade 20b are swung by the biasing force of the spring 25.
Perform a scissors cutting exercise.

Reference numeral 30 is a blocking device, which includes a blocking piece 31 and a drive unit 32. The blocking piece 31 is pivotally supported by a pin 34 at a middle portion thereof to a bracket 33 fixed to the frame. This pin 34
Is set so as to be located on a swing plane as a swing region of the arm 22. Further, due to the rotation of the blocking piece 31, the one end portion 31a thereof is positioned on the swing plane (hereinafter referred to as “stopper position A”) and at a position removed from the swing plane (hereinafter referred to as “escape position B”). It is set to be movable. The end of the one end portion 31a is formed in a flat shape and faces the arm 22 at a slight distance e from the engagement position of the high portion 27a of the cam 27 and the stopper position A of the blocking piece 31.

Further, the drive unit 32 includes the actuator 37 having a shaft 36 protruding by excitation. The electromagnetic actuator 37 is attached to the bracket 33, and the protrusion 36 of the shaft 36 pushes the other end 31b of the blocking piece 31 via a pressing piece 39 attached to the tip of the shaft 36 to rotate the blocking piece 31 to move it. It is set to the stopper position A. Sign
Reference numeral 40 denotes a rod, which is slidably supported by the bracket 33 coaxially with the shaft 36, and at the other end of the blocking piece 31 from the side opposite to the shaft 36 in the pressing body 41 provided at the tip thereof. It is in contact with 31b. Also, this rod 40
Is always urged by the spring 43 to press the blocking piece 31 against the pressing piece 39 of the shaft 36, and when the shaft 36 moves backward, the blocking piece 31 is rotated to set the blocking piece 31 to the escape position B. Is. Reference numeral 45 is a stopper that abuts on a locking piece 46 provided on the rear end side of the shaft 36 and restricts the movement amount of the shaft 36.

Reference numeral 48 indicates a control means for exciting the electromagnetic actuator 37. 49 is a detector that detects the presence or absence of a weft thread at the end of the weft insertion period, 50 is a transmission circuit that issues a weft insertion abnormality signal based on a signal from the detector 49 that there is no weft thread, and 51 is a fixed time period based on this transmission circuit 50. A switching circuit for exciting the electromagnetic actuator 37 by at least the angle at which the lower portion 27b of the cam 27 contacts the roller 26 (θ in FIG. 1) and a power source 52.

Therefore, the weft cutting device C1 according to the first embodiment has the following actions. Now, referring to an example of the timing chart shown in FIG. 3, since the switching circuit 51 is non-conductive during normal operation of the loom,
The blocking piece 31 is set at the escape position B. Therefore, immediately after beating (0 °), the roller 26 reaches the lower portion 27b of the cam 27, the arm 22 swings, and the movable blade 20b and the fixed blade 20a perform a scissors cutting operation to cut the weft thread.

The detector 49 detects the absence of weft (290
)) And the weft insertion abnormal signal are issued from the transmitting circuit 50, the electromagnetic actuator 37 is excited via the switching circuit 51 in response to this abnormal signal, and the blocking piece 31 moves to the stopper position A.
Is set to. In this case, since the main shaft of the loom rotates due to inertia, the cam 27 also rotates accordingly and the roller 26
Tries to reach the lower part 27b of the cam 27. At this time, blocking piece 3
Since 1 is set to the stopper position A, the arm 22 does not reach the lower portion 27b of the cam 27 by the urging force of the spring 25, but moves by e and stops at the one end 31a of the blocking piece 31. Therefore, since the arm 22 does not swing, the scissors cutting motion by the weft cutter 20 is blocked and the weft is not cut. Further, in this case, the arm 22 hits the blocking piece 31, but the pin 34 supporting the blocking piece 31 is in the swing plane of the arm 22. Therefore, for example, instead of the blocking piece 31, an electromagnetic actuator is used. When the arm 36 is directly hit against the shaft 36 of 37 to prevent the arm 22 from swinging, the moment load acting on the pin 34 becomes smaller than the moment load acting on the shaft 36. That much
The blocking device 30 is highly durable. Further, in this case, since the rotating shaft 21 does not move in the axial direction as in the conventional case, a situation that affects the shearing function of the weft cutter 20 is prevented.

Then, after that, when the loom is stopped, the defective weft yarn may be removed, for example, by the same method as described in the related art.

FIGS. 4 and 5 show a weft cutting device C2 according to a second embodiment of the present invention. This is different from the weft cutting device C1 according to the first embodiment in the configuration of the blocking device.

In this blocking device 60, a blocking piece 61 is formed in a plate shape, and one end 61a
Is rotatably supported by a bracket 62 fixed to a frame, and the blocking piece 61 is attracted by an electromagnet 63 as a movable part provided on the bracket 62 so that the other end 61b is positioned on the rotation plane of the arm 22 ( While making the stopper position D), the spring 64 provided on the bracket 62 pulls and supports the blocking piece 61,
When the excitation of the electromagnet 63 is released, the spring 64 is set to a position (escape position E) where the spring 64 escapes from the swing plane. Reference numeral 66 is a plurality of holes formed in the blocking piece 61, and is for reducing the weight of the blocking piece 61. Reference numeral 67 is a hook-shaped guide that is provided on the bracket 62 and restricts the swing amount of the blocking piece 61.

The excitation of the electromagnet 63 is performed by the same control means as in the first embodiment.

Therefore, according to this embodiment, the blocking piece 61 is set to the stopper position D in response to the weft insertion abnormality signal, and the arm 22
Rocking is prevented.

〔The invention's effect〕

As described above, according to the weft cutting device of the present invention, without moving the swing shaft of the weft cutter in the axial direction,
Since the scissors cutting function can be prevented, it is possible to prevent a situation in which the shearing function is affected by the scissors cutting motion, and thus it is possible to prevent cutting failure due to the weft cutter. When the scissors-cutting function is blocked, the biasing force of the link system does not exert a component force on the blocking piece in the weft direction, and the blocking piece does not escape. Since a force is exerted on the piece in the direction perpendicular to its rotation axis, it is not necessary to consider the moment or the like, and therefore, it is possible to prevent damage even if the blocking piece is made lighter.

[Brief description of drawings]

FIG. 1 is a front view showing a weft cutting device according to a first embodiment of the present invention, FIG. 2 is a partial sectional view corresponding to line II-II in FIG. 1,
FIG. 3 is a diagram showing an example of a timing chart of the device according to this embodiment, FIGS. 4 and 5 are front views and side views showing a weft cutting device according to a second embodiment of the present invention, and FIG. FIG. 1 is a perspective view of an essential part showing an example of a conventional weft cutting device. 2, C1, C2 …… Weft cutting device 3,20 …… Weft cutter 4,30,60 …… Blocking device 31,61 …… Blocking piece 32 …… Drive part 63 …… Electromagnet (drive part)

Claims (1)

[Claims] 1. A movable blade, which comprises a fixed blade (3a) and a movable blade (3b) that performs a scissor cutting motion and is swung by a cam (27) that rotates in synchronization with a loom. (3b) movable blade drive link system (21, 22) and blocking device (30, 6) for blocking the scissors cutting motion based on the weft insertion abnormality signal.
0) and the weft cutting device, the blocking device (30, 60) has a rotation axis in a plane including a reciprocating region of the link system from the cam follower to the movable blade,
In addition, a blocking piece (31, 61) having a locking part (31a, 61a) that can advance into the swinging area of the link system, and a blocking piece in the reciprocating movement area in response to a weft insertion abnormal signal. And a drive part (32, 63) for advancing to the, the engagement part (31a, 61a) of the link system has an engagement part orthogonal to the reciprocating direction, and the locking part is the A weft cutting device (C1, C2) in a shuttleless loom, comprising: an abutting portion that is parallel to the engaging portion when it has advanced into the swing region of the link system.