GB2031957A

GB2031957A - Driving looms

Info

Publication number: GB2031957A
Application number: GB7930334A
Authority: GB
Original assignee: STOPANSKI VITEX
Current assignee: STOPANSKI VITEX
Priority date: 1978-10-09
Filing date: 1979-08-31
Publication date: 1980-04-30
Also published as: GB2031957B

Abstract

An arrangement in a weaving loom for stopping the loom in the event of weft thread breakage comprises actuating means (1) which provides a signal in the absence of a weft thread in a shed formed by the loom. This signal results in the disengagement of a first clutch (10), which disconnects the loom drive from a shedding mechanism (13), and engagement of a second clutch 11, which connects a motor (5) to the shedding mechanism (13) to drive the mechanism in the reverse direction to re-open the unfilled shed. Both of these operations are initiated by the rocking of a lever (9) by a cam (8) which is rotated by the motor (5) when the actuating means (1) produces a signal. The lever (9) also actuates a weft insertion mechanism (27) which inserts a fresh weft thread into the re-opened unfilled shed. <IMAGE>

Description

SPECIFICATION An arrangement in a weaving loom for stopping the loom in the event of weft thread breakage This invention relates to an arrangement in a weaving loom for stopping the loom in the event of weft thread breakage.

According to the present invention there is provided, in a weaving loom, an arrangement for stopping the loom in the event of weft thread breakage, the arrangement comprising: actuating means responsive to the presence or absence of a weft thread in a shed formed by the loom and adapted to produce a signal in the event of absence of a weft thread; a motor which is connected to the actuating means so as to be energised by a signal produced by the actuating means; a cam connected to be driven by the motor; a lever which is enaged by the cam so as to be rocked upon movement of the cam; a first clutch connected to the lever so as to be disengaged by rocking of the lever to disconnect a drive of the loom from a shedding mechanism of the loom;; a reversing switch arranged to be actuated by rocking of the lever to engage a second clutch so to connect the motor to the shedding mechanism to drive the shedding mechanism in the reverse direction.

For a better understanding of the present invention, and to show how it may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, which show diagrammatically an arrangement for stopping a weaving loom in the event of weft thread breakage.

The arrangement comprises actuating means in the form of a pin 1 which is acted upon by a mechanism 2 in opposition to a blade spring 3 to close a pair of contacts 19 of a microswitch. The mechanism 2 is responsive to the presence or absence of weft thread passing into a shed formed in the loom. The mechanism 2 comprises a lever 20 which is connected by a first pivot 21 to a slider 22 and by a second pivot 23 to a rod 24. The lever 20 has a follower 25 which is acted upon by a cam 26. The rod 24 is shown only partially in the Figure but its end away from the pivot 23 is allowed to move freely while weft threads are inserted normally into sheds formed in the loom, but is held stationary in the absence of any such weft thread, for example where the weft thread is broken. Arrangements for achieving this are well-known in the weaving art.

The contacts 19 are connected to a control unit 4, which in turn is connerted to supply signals to a motor 5 and to an electromagnetically operated clutch 11. Apart from the contacts 19, there are two further control inputs to the unit 4; these comprise manual push buttons 16 and 17 and a reversing switch 18. The control unit4 also has an indicating lamp 6. The motor 5 is connected by a chain transmission to a cam 8 which acts on one end of a lever 9. The other end of this lever 9 is connected to operate a clutch 10. The lever 9 is provided with an actuating member of the reversing switch 18 and is connected, by a rod 14, to a weft insertion mechanism 27.

The clutch 10 is arranged to connect a drive of the loom to a shedding mechanism 13, through a chain transmission.

In operation, the shedding mechanism 13 forms successive sheds of warp threads, through which sheds are passed weft threads which are then beaten up to form fabric in the conventional manner.

In normal operation, the presence of a weft thread in each shed means that the rod 24 is freely movable, and so the lever 20 rocks about the pivot 21 under the action of the cam 26. The contacts 14 remain open, and so the arrangement shown in the Figure is dormant. However, weft thread breakage will result in no weft thread entering a shed, and this will cause the rod 24 to be held stationary. The lever 20 will thus rock instead about the pivot 23, causing the slider 22 to be moved by the lever 20 to press the pin 1 against the contacts 19. This causes the control unit4to deliver a signal to the motor 5 which is thus energised to rotate the cam 8. At the same time the lamp 6 is illuminated. Rotation of the cam 8 rocks the lever 9 in the direction to disengage the clutch 19, so disconnecting the drive from the shedding mechanism 13, which then stops.Rocking of the lever 9 also causes the reversing switch 18 to be actuated which supplies a signal to the control unit4 resulting in engagement of the clutch 11, which then connects the motor 5 to a sprocket 12. The sprocket 12 is thus rotated to drive the shedding mechanism 13 in the reverse direction so as to re-open the unfilled shed.

The broken thread can then be withdrawn, and the weft insertion mechanism 27, actuated bythe rod 14 displaced by the lever 9, then operates to insert a fresh weft thread into the re-opened shed. Once this operation has been completed, continued rotation of the cam 8 causes the lever 9 to rock back to reengage the clutch 10, so connecting the drive of the loom to the shedding mechanism for normal forward operation.

The push-buttons 16 and 17 are provided for manually operating the loom for a number of cycles, in either direction. The lamp 6 is illuminated when the contacts 19 are closed to provide a visual indication that weft thread breakage has occurred.

1. In a weaving loom, an arrangement for stopping the loom in the event of weft thread breakage, the arrangement comprising: actuating means responsive to the presence or absence of a weft thread in a shed formed by the loom and adapted to produce a signal in the event of absence of a weft thread; a motor which is connected to the actuating means so as to be energised by a signal produced by the actuating means; a cam connected to be driven by the motor;

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION An arrangement in a weaving loom for stopping the loom in the event of weft thread breakage This invention relates to an arrangement in a weaving loom for stopping the loom in the event of weft thread breakage. According to the present invention there is provided, in a weaving loom, an arrangement for stopping the loom in the event of weft thread breakage, the arrangement comprising: actuating means responsive to the presence or absence of a weft thread in a shed formed by the loom and adapted to produce a signal in the event of absence of a weft thread; a motor which is connected to the actuating means so as to be energised by a signal produced by the actuating means; a cam connected to be driven by the motor; a lever which is enaged by the cam so as to be rocked upon movement of the cam; a first clutch connected to the lever so as to be disengaged by rocking of the lever to disconnect a drive of the loom from a shedding mechanism of the loom;; a reversing switch arranged to be actuated by rocking of the lever to engage a second clutch so to connect the motor to the shedding mechanism to drive the shedding mechanism in the reverse direction. For a better understanding of the present invention, and to show how it may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, which show diagrammatically an arrangement for stopping a weaving loom in the event of weft thread breakage. The arrangement comprises actuating means in the form of a pin 1 which is acted upon by a mechanism 2 in opposition to a blade spring 3 to close a pair of contacts 19 of a microswitch. The mechanism 2 is responsive to the presence or absence of weft thread passing into a shed formed in the loom. The mechanism 2 comprises a lever 20 which is connected by a first pivot 21 to a slider 22 and by a second pivot 23 to a rod 24. The lever 20 has a follower 25 which is acted upon by a cam 26. The rod 24 is shown only partially in the Figure but its end away from the pivot 23 is allowed to move freely while weft threads are inserted normally into sheds formed in the loom, but is held stationary in the absence of any such weft thread, for example where the weft thread is broken. Arrangements for achieving this are well-known in the weaving art. The contacts 19 are connected to a control unit 4, which in turn is connerted to supply signals to a motor 5 and to an electromagnetically operated clutch 11. Apart from the contacts 19, there are two further control inputs to the unit 4; these comprise manual push buttons 16 and 17 and a reversing switch 18. The control unit4 also has an indicating lamp 6. The motor 5 is connected by a chain transmission to a cam 8 which acts on one end of a lever 9. The other end of this lever 9 is connected to operate a clutch 10. The lever 9 is provided with an actuating member of the reversing switch 18 and is connected, by a rod 14, to a weft insertion mechanism 27. The clutch 10 is arranged to connect a drive of the loom to a shedding mechanism 13, through a chain transmission. In operation, the shedding mechanism 13 forms successive sheds of warp threads, through which sheds are passed weft threads which are then beaten up to form fabric in the conventional manner. In normal operation, the presence of a weft thread in each shed means that the rod 24 is freely movable, and so the lever 20 rocks about the pivot 21 under the action of the cam 26. The contacts 14 remain open, and so the arrangement shown in the Figure is dormant. However, weft thread breakage will result in no weft thread entering a shed, and this will cause the rod 24 to be held stationary. The lever 20 will thus rock instead about the pivot 23, causing the slider 22 to be moved by the lever 20 to press the pin 1 against the contacts 19. This causes the control unit4to deliver a signal to the motor 5 which is thus energised to rotate the cam 8. At the same time the lamp 6 is illuminated. Rotation of the cam 8 rocks the lever 9 in the direction to disengage the clutch 19, so disconnecting the drive from the shedding mechanism 13, which then stops.Rocking of the lever 9 also causes the reversing switch 18 to be actuated which supplies a signal to the control unit4 resulting in engagement of the clutch 11, which then connects the motor 5 to a sprocket 12. The sprocket 12 is thus rotated to drive the shedding mechanism 13 in the reverse direction so as to re-open the unfilled shed. The broken thread can then be withdrawn, and the weft insertion mechanism 27, actuated bythe rod 14 displaced by the lever 9, then operates to insert a fresh weft thread into the re-opened shed. Once this operation has been completed, continued rotation of the cam 8 causes the lever 9 to rock back to reengage the clutch 10, so connecting the drive of the loom to the shedding mechanism for normal forward operation. The push-buttons 16 and 17 are provided for manually operating the loom for a number of cycles, in either direction. The lamp 6 is illuminated when the contacts 19 are closed to provide a visual indication that weft thread breakage has occurred. CLAIMS

1. In a weaving loom, an arrangement for stopping the loom in the event of weft thread breakage, the arrangement comprising: actuating means responsive to the presence or absence of a weft thread in a shed formed by the loom and adapted to produce a signal in the event of absence of a weft thread; a motor which is connected to the actuating means so as to be energised by a signal produced by the actuating means; a cam connected to be driven by the motor; a lever which is engaged by the cam so as to be rocked upon movement of the cam; a first clutch connected to the lever so as to be disengaged by rocking of the lever to disconnect a drive of the loom from the shedding mechanism of the loom;; a reversing switch arranged to be actuated by rocking of the lever to engage a second clutch so to connect the motor to the shedding mechanism to drive the shedding mechanism in the reverse direction.

2. In a weaving loom, an arrangement as claimed in claim 1, in which a control unit is provided, which routes signals from the actuating means to the motor and routes signals from the reversing switch to the second clutch.

3. In a weaving loom, an arrangement as claimed in claim 1 or 2, in which the actuating means comprises a pin which, in the absence of a weft thread, is moved against a resilient force applied by a blade spring to close the contacts of a microswitch.

4. In a weaving loom, an arrangement as claimed in any one of the preceding claims, in which a weft insertion mechanism is adapted to be actuated by rocking of the lever.

5. In a weaving loom, an arrangement as claimed in any one of the preceding claims, in which pushbuttons are provided for causing movement of the loom in the forward and reverse senses.

6. In a weaving loom, an arrangement for stopping the loom in the event of weft thread breakage, the arrangement being substantially as described herein with reference to the accompanying drawing.