GB1568395A - Mechanism for selecting coloured yarn ends and presenting them to a pile fabric loom - Google Patents

Description

(54) A MECHANISM FOR SELECTING COLOURED YARN ENDS AND PRESENTING THEM TO A PILE FABRIC LOOM (71) We, BRUCE MONTEITH EVANS, 49 James Street, Ayre, Ayrshire, ROBERT JOSEPH HUNTER, 21 Marchlands Terrace, Bo'ness, West Lothian, and JAMES EDGAR GAULT, 77 Whitlees Court, Ardrossan, Ayrshire all British subjects do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a mechanism for selecting coloured yarn ends and presenting them to a pile fabric loom. This invention also includes a pile fabric loom when including the mechanism.

It is known that a pile fabric loom, for example for producing Axminster carpet, operates by having a row of appropriately coloured yarn ends presented to it. The loom cuts tufts from the yarn ends and weaves them into the fabric. The colour of each tuft in each position is altered for each cycle of the loom and thus a multi-coloured pattern is produced.

The present invention provides a mechanism for selecting coloured yarn ends and presenting them to a pile fabric loom, which mechanism comprises: (A) a yarn-carrying device comprising a plurality of selector rods, a plurality of holes in each rod, and a yarn non-return mechanism for each hole, and (B) a positioning device for moving the selector rods to predetermined positions before the commencement of each weaving cycle so that appropriately coloured yarn ends are presented for each weaving cycle, the positioning device comprising a plurality of positioning members, an elongate member for moving the positioning members, monitoring means for monitoring the position of the positioning members, and electrically-actuated means having a stop member for engaging each positioning member and causing the positioning members to correctly position the selector rods whilst appropriate yarns are taken from the yarn non-return mechanims.

The mechanism may include guides for each selector rod to slide in.

Preferably, there is a positioning member for each selector rod. Each positioning member may be directly or indirectly attached to its selector rod. In some instances, one positioning member may control several selector rods spaced across the loom, for example for repeating a pattern.

Each positioning member may be a toothed rod, the stop member engaging in the teeth. Alternatively, each positioning member may be a rod, for example a smooth rod, having a surface which has a high coefficient of friction, the stop member engaging the positioning member by means of friction, the stop member engaging the positioning member by means of friction. In both of these embodiments, the elongate member may conveniently be a beam which moves linearly.

Alternatively, each positioning member may be a toothed wheel, the stop member engaging in the teeth. The toothed wheel may be supported on a shaft, the shaft being adapted to rotate for a limited amount within the toothed wheel, and the shaft constituting the elongate member.

Usually, the elongate member will move between two set positions irrespective of the position at which any of the positioning members are stopped. Preferably, the elongate member will return all the positioning members to a starting position on each of its return journies. Alternatively, the elongate member may on either of its outward or return journies alter the position of the positioning member by selectively engaging and disengaging the stop member at appropriate points between the two set positions. In this latter case, the positioning member prefer ably has square shaped teeth rather than saw shaped teeth, and it also preferably has a friction mechanism or an indexing mechanism to retain it in a fixed position when the stop member is disengaged.

The monitoring means may include transducers and an electronic control unit.

Preferably, the electrically-actuated means is a solenoid but other devices can be employed if desired.

Embodiments of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 shows part of a yarn-carrying device; and Figures 2,3 and 4 show part of first, second and third positioning devices respectively.

Referring to Figure 1, there is shown part of a yarn-carrying device comprising a plurality of selector rods. For simplicity of illustration, only one selector rod 6 is shown but in fact there will be a selector rod 6 for each tuft position. Each rod 6 has a number of transverse holes as shown. Each hole is equipped with a yarn non-return mechanism 5 and is threaded with a yarn 7 which is differently coloured from the yarns in all the other holes in the rod 6. Each rod 6 slides in guides 1, 2,3 and 4, which are located as shown above and beneath the yarn carriers. Alternatively, the guides 1, 2, 3 and 4 can be positioned parallel to the yarn carriers and located between them.Each rod 6 is moved by a positioning device to be described hereinbelow in such a way that for every weaving cycle, an appropriately coloured yarn end is presented in the correct weaving position. An appropriate connecting mechanism may connect the rods 6 to the positioning device. While the tufts are being woven into the fabric, the rods 6 are repositioned to select the next row of colours. The commencement of the next weaving cycle is inhibited until the rods 6 are correctly positioned.

Referring now to Figure 2, there is shown part of a positioning device comprising a plurality of positioning rods. For simplicity of illustration only one positioning rod 8 is shown. This positioning rod 8 has a lip 9 and serrated teeth 17 and it is constained to move in one dimension by guides 10, 11, 12 and 13.

An elongate member in the form of a beam 14 moves all the rods 8, which are places side by side, to the position shown. The beam 14 then moves to the dotted position shown which is just short of the guide 13. The rod 8, aided by gravity of a spring, follows it. As the rod 8 moves, its position is monitored by monitoring means in the form of suitable transducers which send electrical signals to an electronic control unit. When an associated selector rod 6 is in the correct position, a solenoid 15 is activated, driving a plunger 16 into engagement with the teeth 17 and thereby stopping the further movement of the rod 8 and its associated selector rod 6.

The beam 14 continues to the final position of its movement, by which time all the solenoids 15 will have been energised at the appropriate time, thus positioning all the coloured yarns.

After the tufts have been taken from the yarn-carrying device, the solenoids 15 are released, and the beam 14 returns to its starting position taking all the rods 8 with it. The cycle then repeats for the next row of the pattern.

If physical size constaints prevent the solenoids 15 from being placed side by side on adjacent rods 8, they may be stacked in several rows. The rods 8 will then have correspondingly more teeth to cater for the fact that the solenoids 15 are at different levels.

The selector and positioning rods 6, 8 for each position have been described separately for clarity. In practice they could be incorporated into one unit. They could be attached directly together or they could be indirectly attached using wire and pulleys, for example, and mounted in different directions.

The information on which coloured yarns are to appear in each position for each row of the pattern is held on a suitable electronically readable medium, for example a magnetic disc, a magnetic tape or punched paper tape.

This information is decoded by the electronic control unit so that the electronic control unit knows which solenoids 15 are to be activated at each location in the movement of the rods 6, 8. Alternatively, a unit adapted to read decoded data may be used. As the control unit receives the electronic signals indicating the position of the rods 6, 8, it energises the appropriate solenoids 15.

The yarn-carrying device described above with reference to Figure 1 may be regarded as a conventional Jacquard yarn carrier but it will normally carry many more colours.

If desired, the plunger 16 described above with reference to Figure 2 can act directly as shown on the rod 8, or indirectly through a linkage, not shown. The plunger 16 need not disengage when it is de-energised but may continue to support the rod 8 until the beam 14 removes the load from the plunger 16.

A positioning device which is alternative to that shown in Figure 2 but which can still be used with the yarn-carrying device shown in Figure 1 will now be described with reference to Figure 3.

Referring to Figure 3 a single positioning member is shown for clarity but in fact a plurality of these positioning members x be employed. The positioning member comprises a toothed wheel 21 which is free to turn on an elongate member in the form of a shaft 22, but is limited in its angular rotation with respect to the shaft 22 by a peg 23 which is securely fixed to the shaft 22. This peg 23 encounter is a protrusion 24 on the wheel 21 and thus allows the wheel 21 to make only limited angular movement around the shaft 22. In operation, the shaft 22 rotates clockwise and the wheel 21 initially remains stationary, held by a plunger 27, until the peg 23 encounters the protrusion 24. The shaft 22 and the wheel 21 then rotate together until the shaft 22 reaches the reference position shown in Figure 3. The shaft 22 then rotates anti-clockwise.

The wheel 21 is permanently urged by external means to rotate anti-clockwise and it therefore follows the shaft 22. As the shaft 22 moves, its position is monitored by suitable transducers which send electrical signals to an electronic control unit. When the toothed wheel 21 is in the correct position, a solenoid 26 is activated, driving a plunger 27 into engagement with the teeth 28 on the wheel 21 and preventing the further rotation of the wheel 21. The shaft 22 continues-to rotate until it reaches its final position, by which time all the solenoids 26 (only one being shown) will have been energised at their appropriate times, thus positioning all the wheels 21 (only onw being shown) and therefore the attached yarn carriers, shown for example in Figure 1.After the tufts have been taken from the carriers, the solenoids 26 are released, and the shaft 22 returns to its reference position, taking all the wheels 21 with it. The cycle then repeats for the next row of the pattern. Various mechanisms may be employed to impart the necessary oscillatory movement to the shaft 22.

The connecting mechanism for connecting the yarn-carrying device and the positioning device can be any mechanism converting rotary to linear motion. Thus, for example, a pulley may be affixed to the wheel 21 with a cord connected to the yarn carrier shown in Figure 1. Alternatively, the wheel 21 may incorporate a pinion engaging with a rack attached to the yarn carrier.

Referring now to Figure 4, a solenoid 32 is raised by a lifting knife (not shown). A positioning member in the form of a rod 29 remains stationary, held either by friction or an index mechanism (not shown), until the solenoid 32 is energised when a plunger 31 engages with teeth 30 on the rod 29 and causes the rod 29 also to rise. The lifting knife carrying all the solenoids 32 (only one being shown) stops at a fixed position at the top of its stroke, thus positioning the yarn carriers for yarn draw-off. The solenoids 32 are de-energised but the rod 29 remains stationary again held either by friction or by the index mechanism. The knife then descends.

Rods 29 which require to be lowered a certain distance for the next yarn draw-off will have their corresponding solenoids 32 engaged only during the descent of an elongate member (not shown), and the solenoids 32 will disengage when the elongate member has reached a fixed position at the bottom of its stroke, thus positioning these rods 29.

Positioning rods 29 which do not require to be moved between consecutive yarn drawoff's will have their corresponding solenoids de-energised during the complete cycle.

Positioning rods 29 which require to be raised before the next yarn draw-off will execute the process initially described.

It is to be appreciated that the embodiments of the invention described above have been given by way of example only and that modifications may be effected. Thus, for example, Figure 2 may be modified such that the solenoid 15 is raised by a lifting knife (not shown) and the guide 13 is removed. The rod 8 remains stationary until the solenoid 15 is energised, when the plunger 16 engages with the teeth 5 and cuases the rod 8 also to rise.

The lifting knife carrying the solenoids 15 (only one being shown) stops at a fixed position at the top of its stroke, thus positioning the yarn carriers for yarn draw-off. The solenoids 15 are de-energised, the knife descends and the cycle repeats.

WHAT WE CLAIM IS: 1. A mechanism for selecting coloured yarn ends and presenting them to a pile fabric loom, which mechanism comprises: (A) a yarn-carrying device comprising a plurality of selector rods, a plurality of holes in each rod, and a yarn non-return mechanism for each hole, and (B) a positioning device for moving the selector rods to predetermined positions before the commencement of each weaving cycle so that appropriately coloured yarn ends are presented for each weaving cycle, the positioning device comprising a plurality of positioning members, an elongate member for moving the positioning members, monitoring means for monitoring the position of the positioning members, and electrically-actuated means having a stop member for engaging each positioning member and causing the positioning member to correctly position the selector rods whilst appropriate yarns are taken from the yarn non return mechanisms.

2. A mechanism according to claim 1 including guides for each selector rod to slide in.

3. A mechanism according to claim 1 or claim 2 in which there is a positioning member for each selector rod.

4. A mechanism according to claim 3 in which each positioning member is directly or indirectly attached to its selector rod.

5. A mechanism according to any one of the preceding claims in which each positioning member is a toothed rod, the stop member engaging in the teeth.

6. A mechanism according to claim 5 in

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

Claims (13)

**WARNING** start of CLMS field may overlap end of DESC **. encounter is a protrusion 24 on the wheel 21 and thus allows the wheel 21 to make only limited angular movement around the shaft 22. In operation, the shaft 22 rotates clockwise and the wheel 21 initially remains stationary, held by a plunger 27, until the peg 23 encounters the protrusion 24. The shaft 22 and the wheel 21 then rotate together until the shaft 22 reaches the reference position shown in Figure 3. The shaft 22 then rotates anti-clockwise. The wheel 21 is permanently urged by external means to rotate anti-clockwise and it therefore follows the shaft 22. As the shaft 22 moves, its position is monitored by suitable transducers which send electrical signals to an electronic control unit. When the toothed wheel 21 is in the correct position, a solenoid 26 is activated, driving a plunger 27 into engagement with the teeth 28 on the wheel 21 and preventing the further rotation of the wheel 21. The shaft 22 continues-to rotate until it reaches its final position, by which time all the solenoids 26 (only one being shown) will have been energised at their appropriate times, thus positioning all the wheels 21 (only onw being shown) and therefore the attached yarn carriers, shown for example in Figure 1.After the tufts have been taken from the carriers, the solenoids 26 are released, and the shaft 22 returns to its reference position, taking all the wheels 21 with it. The cycle then repeats for the next row of the pattern. Various mechanisms may be employed to impart the necessary oscillatory movement to the shaft 22. The connecting mechanism for connecting the yarn-carrying device and the positioning device can be any mechanism converting rotary to linear motion. Thus, for example, a pulley may be affixed to the wheel 21 with a cord connected to the yarn carrier shown in Figure 1. Alternatively, the wheel 21 may incorporate a pinion engaging with a rack attached to the yarn carrier. Referring now to Figure 4, a solenoid 32 is raised by a lifting knife (not shown). A positioning member in the form of a rod 29 remains stationary, held either by friction or an index mechanism (not shown), until the solenoid 32 is energised when a plunger 31 engages with teeth 30 on the rod 29 and causes the rod 29 also to rise. The lifting knife carrying all the solenoids 32 (only one being shown) stops at a fixed position at the top of its stroke, thus positioning the yarn carriers for yarn draw-off. The solenoids 32 are de-energised but the rod 29 remains stationary again held either by friction or by the index mechanism. The knife then descends. Rods 29 which require to be lowered a certain distance for the next yarn draw-off will have their corresponding solenoids 32 engaged only during the descent of an elongate member (not shown), and the solenoids 32 will disengage when the elongate member has reached a fixed position at the bottom of its stroke, thus positioning these rods 29. Positioning rods 29 which do not require to be moved between consecutive yarn drawoff's will have their corresponding solenoids de-energised during the complete cycle. Positioning rods 29 which require to be raised before the next yarn draw-off will execute the process initially described. It is to be appreciated that the embodiments of the invention described above have been given by way of example only and that modifications may be effected. Thus, for example, Figure 2 may be modified such that the solenoid 15 is raised by a lifting knife (not shown) and the guide 13 is removed. The rod 8 remains stationary until the solenoid 15 is energised, when the plunger 16 engages with the teeth 5 and cuases the rod 8 also to rise. The lifting knife carrying the solenoids 15 (only one being shown) stops at a fixed position at the top of its stroke, thus positioning the yarn carriers for yarn draw-off. The solenoids 15 are de-energised, the knife descends and the cycle repeats. WHAT WE CLAIM IS:

1. A mechanism for selecting coloured yarn ends and presenting them to a pile fabric loom, which mechanism comprises: (A) a yarn-carrying device comprising a plurality of selector rods, a plurality of holes in each rod, and a yarn non-return mechanism for each hole, and (B) a positioning device for moving the selector rods to predetermined positions before the commencement of each weaving cycle so that appropriately coloured yarn ends are presented for each weaving cycle, the positioning device comprising a plurality of positioning members, an elongate member for moving the positioning members, monitoring means for monitoring the position of the positioning members, and electrically-actuated means having a stop member for engaging each positioning member and causing the positioning member to correctly position the selector rods whilst appropriate yarns are taken from the yarn non return mechanisms.

2. A mechanism according to claim 1 including guides for each selector rod to slide in.

3. A mechanism according to claim 1 or claim 2 in which there is a positioning member for each selector rod.

4. A mechanism according to claim 3 in which each positioning member is directly or indirectly attached to its selector rod.

5. A mechanism according to any one of the preceding claims in which each positioning member is a toothed rod, the stop member engaging in the teeth.

6. A mechanism according to claim 5 in

which the elongate member is a beam which moves linearly.

7. A mechanism according to any one of claims 1-4 in which each positioning member is a toothed wheel, the stop member engaging in the teeth.

8. A mechanism according to claim 7 in which the toothed wheel is supported on a shaft, the shaft being adapted to rotate for a limited amount within the toothed wheel, and the shaft constituting the elongate member.

9. A mechanism according to any one of the preceding claims in which the elongate member moves between two set positions irrespective of the position at which any of the positioning members are stopped, the elongate member returning all the positioning members to a starting position on each of its return journies.

10. A mechanism according to any one of the preceding claims in which the monitoring means includes transducers and an electronic control unit.

11. A mechanism according to any one of the preceding claims in which the electrically-actuated means is a solenoid.

12. A mechanism for selecting coloured yarn ends and presenting them to a pile fabric loom, substantially as herein described with reference to the accompanying drawings.

13. A pile fabric loom whenever including a mechanism as claimed in any one of the preceding claims.