GB1030965A - Improvements in textile ring spinning and twisting machines - Google Patents

Abstract

In ring-spinning apparatus of the kind in which the ring-rail is driven upwardly by a cam engaging a builder-lever, the return stroke being effected by gravity, and the "gain" is brought about by shortening the builder-chain, in order to form a tip-bunch, means are provided to exist a pull on the chain to raise the ring-rail beyond the uppermost position it attains in the normal build, together with means for temporarily retaining the rail in the position to which it is so raised. The pull on the yarn can be effected (a) by depressing the builder lever below its normal lowest position, or (b) by deflecting the chain, or (c) by taking up a length of chain by a reversible electric motor selectively engageable with the drum on which the chain is wound to provide the gain. In (a) the retaining-means is a catch, in (b) solenoid-operated means, and in (c) a brake associated with the auxiliary motor. The preferred embodiment is of form (a), and comprises a builder lever 19, Fig. 2 (not shown), which is normally rotated by a cam 17. The chain 21 is taken up for the gain by an intermittently-rotated drum 28. Chain- and sprocket gearing Fig. 1, (not shown), connects the free end of the lever to a shaft 25 on which a drum 26 at each side of the machine is connected to a yoke 16 fastened to the ring-rails, the yoke sliding in a slot in an end-member of the frame. When the normal build is completed, the builder lever 19 is further depressed when an abutment 30, pivoted on the lever, is displaced to engage a roller 52 on a wheel 51 rotating with the builder-cam. The abutment is in the upper arm of a double-lever of which the lower arm depends into a slot in a guide 37 slidable in the lever 19, the right-hand end 40 of which acts as an abutment to help restrain the lever from movement under the influence of a spring 36. The lever 31 is also restrained from movement by a catch 33 forming part of a double lever of which the lower end depends into a slot 38 on the slide and is maintained in engagement position by a spring 35. The slide is urged to the left by a spring 42. When the normal build has been completed, the chain has been so wound up on drum 28 that a projection on the chain engages the slide and moves it to the right to release the catch 33 and allow the spring 36 to rock lever 31 and bring the abutment 30 against roller 52. As the builder lever is depressed, an adjustable detent 44 on its free end rides down the upper face of a spring-urged catch 45 pivoted on a fixed part and snaps into a recess to hold the lever and hence the ring-rail in the positions to which they have been moved. A time switch allows a desired length of yarn to be wound to form a tip-bunch; at the end of this operation a winding-down motor begins to wind chain 21 off drum 28 so that the ring-rail falls by gravity to a doffing position where it is arrested by a stop. The chain is further unwound so that the lever is allowed to drop, when detent 44 runs down the lower face of catch 45 and cause its upper end to engage a recess in a pivoted latch 48, so that the builder lever is free to use again. Spring 42 has now returned the slide and its associated parts to their starting-positions; the latch 48 is freed as the ring-rail rises.