Patent GB-474669-A (GB)
Title: Improvements in or relating to looms
IPC: D03D51/00
Filed: 1936-04-01
Abstract: 474,669. Looms. MILLIAT, L., and SOC. LYONNAISE DES MACHINES TEXTILES. April 1, 1936, No. 9711. [Classes 142 (i) and 142 (iii)] In a loom in which a component group such as a dobby or jacquard or change-box mechanism is hand-controlled, e.g. so that the dobby can be reversed for finding the pick-by apparatus comprising a first clutch normally transmitting drive from the loom to the dobby &c., and a second clutch coupling the dobby &c. with an auxiliary drive, the construction is such that on operation of the hand control the first clutch is disengaged, then the second clutch is briskly engaged and remains engaged during one complete revolution thereof, whereupon the first clutch becomes re-engaged automatically unless restrained from so doing by the operator holding the control, the second clutch being disengaged. at the same tune as such re-engagement. The first clutch comprises an element 4 slidable on but rotating with a shaft 1, and an element 6 loose on 1 and having a dog 5 which engages in a slot in 4. Normally the dobby shaft 11 is driven from the loom via chain 3, sprocket 2 fast on 1, clutch 4, 6, gear 8 integral with 6 and pinion 9 splined on 11. The second clutch comprises a toothed plate 12 integral with gear 8, and a toothed plate 13 integral with a gear 15 loose on 1. To drive the dobby in reverse the loom, and therefore shaft 1, is stopped and the drive is deflected via a loose pulley arrangmement (not shown) so as to drive shaft 19. Gear 16, rotating with 19, is slid along 19 to engage with and drive gear 15 and hence clutch plate 13. The hand control is now operated to disconnect 4, 6 and connect 12, 13. The control comprises a shaft 39 rigid with a cam plate 42 having a slot 40 in which engages a pin 41 extending from a cam plate 38 loose on shaft 39, a rod 48 rigid with 39, and a pull-rod 49. The operator pulls down the rod 49. This rotates plate 42 and a roller 47 rides up its surface and thereby pivots the lever system 46, 28, about 31, lever 28 being moved to the left and with it element 4 against a spring 10. A sleeve 30, fixed to 28 and sliding on a lever 32, thus compresses a spring 34 on 32 against a collar 35 fixed to 32. Plate 38 is rotated, by means of pin 41, with 42, and when element 4 has been disengaged from element 6, roller 37 falls off 38 and the lever system 36, 22, 32 is swung quickly anticlockwise around pivot 27 by the compressed spring 34, 13 being thus engaged with 12. As long as the operator holds down the handle 49, shaft 11 is driven from shaft 19. If he releases it immediately, the tensed spring 43 returns plate 42 to its original position, roller 47 falls off 42, and spring 10 pushes 4 against 6 until clutch 12, 13 has completed one revolution, whereupon the slot in 4, now registering with the dog 5, engages the dog; hence lever 28 moves to the right and with it, via sleeve 30 and a collar 33 fixed to 32, moves lever 22, 13 being thus disengaged from 12. To drive the dobby forward from shaft 19, gear 18, which meshes with gear 17, is engaged with gear 15. In a slightly modified construction, gear 8 is fast on shaft 1 and the clutch elements 4, 6 are fixed on the ends of independent shafts. The clutches shown may be replaced by friction clutches, the cams by rods and cranks or toothed sectors and racks, and the connection 15, 16 may be replaced by a clutch-controlled chain connection.