| 摘要 |
1,167,466. Repositioning spinning frame travellers prior to doffing. BARBER-COLMAN CO. 12 Feb., 1968 [13 Feb., 1967], No. 6829/68. Heading DID. A head 10, which is moving continuously along a spinning frame and operates on each spinning unit to doff a filled bobbin 12 and don a replacement bobbin 23, has mounted thereon a mechanism which on passing each successive spinning unit operates to shift the traveller 14 thereof around its supporting ring 15 and stop it at a desired position X. Such repositioning is effected by turning each successive bobbin and spindle to swing the unwound thread 13 and traveller around the ring and against a stop 17 which is mounted on the head for movement into and out of stop positions X for each spinning unit in turn. Before repositioning is effected each unwound thread between its traveller and thread eye 18 is separated from the wound mass 19, and then the bobbin is turned in the unwinding direction to unwind some thread from the base bunch 21. Separation of unwound thread from bobbin. The separation is accomplished by a finger 69 mounted in the head and positioned to engage the thread above the bobbin nose. Advancement of the head causes the thread to be bent forward and to be separated from the main mass. The unwound separated thread thus separated is released from the finger only when pin 77 engages an extension 47 of the thread eye of the next spinning unit. Thread tension sensor. Shortly after the unwound thread is engaged by finger 69 it is also engaged by feeler 78 of a device 79 which senses a predetermined tensioning of the thread and in response thereto causes interruption of the turning of the bobbin in the winding direction. Rotating bobbin to unwind thread. The bobbin is turned in the unwinding direction to increase by a limited amount the length of unwound thread between the traveller and drafting rollers 31. The unwinding is effected by applying a friction torque to the thread by means of a continually rotating cylindrical roll 91 (Figure 2) mounted in the head behind the finger 69. Bobbin turning for traveller repositioning. The bobbin turning is effected by a second roll 108 (Fig. 7) engaging the thread mass for a period terminated by tension sensor 79 actuating clutch 116. After the traveller reaches desired point X and is stopped by stop 17 (Fig. 7) the tension in thread 13 increases since continued turning results in winding some of the loose thread onto the base bunch. Traveller stop. A plurality of stops 17 are spaced, according to the pitch of the spindles, along an elongated endless carrier 123 mounted on the head. The stops travel relative to the head reversely of and at the same speed as the head so as to be stationary relative to a passing spindle. A thread 17 dwells in the thread intercepting position after the traveller has reached position X and is then retracted so as not to disturb the traveller position. This is accomplished by an upright rod 144, suspended via spring 147 from bracket 148 mounted on the head, which engages the hooked end of the stop and swings it clear of the ring 15 as the stop 17 advances around the trailing end of carrier 123. |
