Patent GB-1192357-A (GB)
Title: Improvements relating to the Spinning of Textile Yarns
Inventor: MAKEHAM SAM ROBERT
IPC: D01H4/50
Filed: 1966-09-02
Abstract: 1,192,357. Open end spinning. T.M.M. (RESEARCH) Ltd. 24 Aug., 1967 [2 Sept., 1966], No. 39333/66. Heading D1D. A method of piecing up an open-end spinning chamber after yarn breakage or on starting spinning comprises starting the fibre feed, e.g. delivery rollers 32, 33, arranging for the yarn attached to the take-up reams 44, 45 to follow an extended path, e.g. as shown in the chain dotted lines between the delivery tube 40 and the take up means 44, 45 and then shortening the yarn path to the position shown in full line to allow the end of yarn to contact and pick-up the fibres on the collecting surface and drawing off the continuous length of yarn produced. In the form shown when yarn 41 leaves the collecting surface, fibre delivery rollers 32, 33 and the take-up means 42, 43, 44, 45 are immediatly stopped, brakes being applied if necessary. Simultaneously drive to rotor 37 is stopped to allow the rotor to gradually run to rest. After a time delay a bar 49 with a yarn engaging pin 50 is moved horizontally, deflecting the yarn and drawing off the yarn which is still being formed from the collecting surface. Finally the suction through the chamber applied to its casing 39 is switched off. On restarting, the suction pump and rotor drive are first established. Then rollers 32, 33 are started and bar 49 begins to move back to its normal position thus allowing the extra yarn length to be sucked back into the chamber to join the freshly forming yarn. Finally the draw-off rollers 42, 43, and take-up means 44, 45 are started to take up the newly formed thread Microswitches 52, 53 may be operated by an abutment on bar 49 to initiate some of the operations and to limit the movement of bar 49. In Fig. 1 not shown, on yarn breakage the feed rollers (11, 12) and draw-off rollers (19, 20) are stopped while the rotor (15) continues to run at normal speed. The yarn (17) is taken from the delivery tube (18) and passed via a guide (22) to a cutter (23) which cuts the yarn end to a predetermined length. The end is then inserted into the rotor, the yarn passing about guide (22) to follow an extended path. The feed and draw-off rollers are then started and the yarn is pulled from guide (22) by the draw-off rollers. The extra yarn length allows the yarn end to begin picking up fresh fibres before being drawn from the chamber; thus piecing is accomplished. In Fig. 2 not shown, the yarn on leaving the delivery tube (18) passes along a pivoted guide tube (28) which is normally in a position such that the yarn in its travel to the draw-off rollers passes along an extended path. When the yarn becomes detached from the fibre collecting surface the resulting drop in tension is sensed by a known device, the drawoff rollers (29, 30) are stopped and the pivoted tube (28) pivoted to clamp the yarn between its end and a stop (31). On restarting the tube (28) is pivotted to a position which shortens the yarn path to allow the end to be drawn back into the rotor and draw-off rollers (29, 30) are started; normal spinning is thus resumed. Tube (28) is gradually pivoted back to its "yarn extending" position in readiness for a subsequent piecing operation.