GB714690A - Positive and constant-tension warp letoff mechanism for textile machines - Google Patents

Abstract

714,690. Hydraulic clutches. WHITIN MACHINE WORKS. May 16, 1951, No. 11492/51. Class 69 (2). [Also in Groups VIII, IX and XVI] A shaft 51, driving a warp beam shaft 65 through worm and worm gear 50, 60 carries a member 75, contoured to conform with the annularly recessed opposing faces of a constantly rotating clutch member 40 and a stationary brake member 70 : the members 40, 70, 75 are immersed in oil and member 70 is so positioned axially by a screw 55 that the oil drag between members 40 and 75 drives shaft 51 against the drag between members 70 and 75. An increase in yarn tension causes gear 60 to force shaft 51 to the right, against the action of a return spring 85, to increase the driving torque and decrease the braking torque, to speed up the shaft. The spring 85 may be adjusted initially by means of a thimble 89. The force of spring 85 is also reduced automatically as the yarn is consumed For this purpose, the shaft 65 carries a cam 140 by which a pawl 131, carried on a lever 137, is caused to rack round a shaft 114 to an extent determined by a screw 145. The shaft 114, in turn, carries a cam 115 which acts on a pawl 105, through link 111, to rack round a worm 100 to an extent determined by a screw 120. The worm 100 rotates a worm wheel 95, which has screw threaded engagement with a cylinder 83 containing the spring and which, as it is rotated, allows the cylinder to slide to the right. The clutch member 40 is rotated from the knitting-machine cam shaft. The pawl 105 may be raised clear of its ratchet, to permit manual reverse rotation of worm 100, by rotating a threaded knob to raise a collar 122 through which the link 111 slides.