GB1296936A - - Google Patents

Abstract

1296936 Yarn piecing apparatus SCHUBERT & SALZER MASCHINENFABRIK AG 19 April 1971 [3 Feb 1970] 20863/71 Heading DID A method for piecing broken yarn ends on a ring spinning device comprises detecting the spinning station in which the yarn is broken, locating the ring traveller 141 on the spinning ring 140 associated with said spinning station, arranging an auxiliary yarn H in front of the spinning station between the spinning ring 140 and its associated drafting device 11, passing one end of the auxiliary yarn H under the ring traveller 141 and attaching the other end to the roving running from the drafting device 11, while the end of the auxiliary yarn arranged under the ring traveller 141 is brought against the rotating cop. In one embodiment, the piecing device is mounted in a housing 2 which is movable along the spinning frame 1 to photo-electrically detect a broken yarn and to align it with the appropriate spinning station in known manner. The auxiliary yarn H is initially drawn off a supply spool S by hand, through a guiding eye 30, a gripping device 31, a yarn metering device 32 and a further gripping device 31', and its end is introduced into the vertical part of a stationary tube 40. Following the alignment of the piecing device at a spinning station with a broken yarn, the various parts of the piecing device are actuated in appropriate sequence by a series of cams mounted for rotation with a driven shaft 26. Gripping device 31 is opened and gripping device 31' is closed, and the necessary length of auxiliary yarn H is drawn off from the spool S by the spreading apart of the prongs 321, 321' of two pairs of rake-like parts 320, 321 of the metering device 32. Gripping device 31 is then closed, gripping device 31' opened, and the parts of the device 32 returned to their original positions. Compressed air is now introduced into the horizontal part of the tube 40 to draw the yarn H down the vertical part, through the horizontal part and into a bent tube 41 which tube 41 passes through a hollow shaft 41' and terminates in a nozzle 410' pointing vertically upwards. The free end of the yarn M emerges from the nozzle 410' passes between shield plates 43 and into a guide tube 42, aided by compressed air supplied through a bent tube 410 to an auxiliary nozzle 410', and is loosely held at a point just below the tube 42 by a gripping device 44. The compressed air supply is now shut off and the gripping device 31' closed. The ring traveller 141 is now located and brought to the front side of the ring rail 14 where it is either held or, if it is to be replaced by a new traveller 410, is thrown out of the ring 140, and at the same time the tube 41 is rotated so that its bent end 410 is moved into an approximately horizontal position with its nozzle opening 410' directed towards the ring 140 and the tube 41 is then moved axially with the shaft 41' until the bent end 410 is approximately tangent to the cop on the spindle. The yarn H is then threaded into the traveller 141 or into a new traveller 410 which latter is then pressed onto the ring. An attaching means 8 is then pivoted to strike against the yarn H and displace it out of the guide tube 42 towards the drafting rollers 11 and the gripping device 44 is now pressed to firmly hold this end of the yam H. The yarn H exposed between the tube 40 and the now upturned end 411 of the tube 41 is severed by a cutting device 48 and immediately following this an arm 49 is swung (as shown in Fig. 2) to draw most of the yarn H out of the tube 41 and then a current of air is blown through a tube 45' into the end 411 of the tube 41 to throw the end of the yarn H out of the tube 41 and against the cop so that it is entrained thereby. The arm 49 is now released to free the yarn H which, by virtue of the twist imparted to it, is caused to piece with the roving emerging from the drafting rollers 11. In another embodiment, (Fig. 6 not shown) the device for the pneumatic placement of the auxiliary yarn H is replaced by a mechanical placement device.