823,211. Changing bobbins and tensioning thread in winding machines. REINERS, W. Oct. 4; 1955 [Oct. 4, 1954; Nov. 12, 1954],No. 28304/55. Class 120(2) In an automatic bobbin-changing winding machine, the thread from a wound bobbin is gripped temporarily near one end of the empty bobbin but without touching the body thereof and is released when the rotational speed of the empty bobbin reaches a predetermined value. In the machine shown in Fig. 1, a spindle head 1 is driven by a shaft 2 flexibly coupled by means of a lever 3 to driving belts 4 and 5 through a spring, and a guide 6 mounted in a rod 7 effects traverse of a thread F. When a bobbin held between head 1 and a counter-holder 8 is fully wound, it is released by rotation of lever 3 (moving shaft 2 to the left) and falls into a trough 10 where it is carried by a slide 11 actuated by a shift rod 12 into the position shown in broken lines whereupon thread passes in front of head 1 and lies opposite a clamping-separating member 21, 23; such latter movement may be assisted by guides 14 and 15 on slide 11. As shown in Fig. 4, the shift of shaft 2 actuates the bobbin ejection and movement of ejector 17 is transferred through an arm 20 engaging a notch 19 to member 21. Automatic introduction of a fresh bobbin, during which shaft 2 returns to its right-hand position, forces ejector 17 to the left to impel a shear edge of member 21 which coacts with a counter knife 22 to sever the thread and leave an end trapped between member 21 and spring 23, Fig. 7. When a few turns of thread have been wound on the bobbin, the centrifugal force exerted by rotation of a mass 24 lifts spring 23 to release the clamped thread end which is thereafter entrapped by the windings. An air stream produced, for example, by blades 51, Fig. 3, and passed through one or more bores 52 to the inner cavity of head 1, may impinge directly or indirectly on the thread end to ensure its incorporation in the wound package. In the construction of Fig. 15, the clamped thread end is pulled clear of spring 23 by a !hook 50 actuated by mechanism (not shown) responsive to the speed of rotation of the bobbin. Automatic spindle alignment. At each bobbin change, shaft 2 is automatically aligned to the same angular position by mechanism, Figs. 8-10, comprising a notched wheel 31 and a spring-loaded toggle lever 33 which is rocked (against a stop 34) by a shaft 36 in correspondence with rotation of lever 3 so that the notch 32 is engaged and shaft 2 locked only after head 1 has been moved to the left and shaft 2 coupled to a slow and slipping counter drive from belt 5. Alternative mechanism, Figs. 11-13, comprises a cam 41 and a spring-loaded bearing lever 42 which is rocked (against a stop 44) in correspondence with rotation of lever 3 to force cam 41 (and therefore shaft 2) to rotate to the position shown in Fig. 12. As shown in Fig. 14, lever, 3 in shifting the shaft 2 also acts as a locating lever by a prism end 46 bearing against a cam 47, return movement of shaft 2 into the winding position being effected by the back of the prism 46 engaging a collar 45. If head 1 is provided with several, angularly disposed, thread clamping- separating devices one of which will engage the thread and each associated with an ejector 17, Figs. 16 and 17 (not shown), then the aligning mechanism is unnecessary. Tensioning thread in a reserve length. When the bobbins are changed but before winding has commenced on the fresh bobbin, a thread loop or reserve is formed between a tensioner and the bobbin, the length of the reserve corresponding to one or more turns around the bobbin. In the machine shown in Figs. 18 and 19, a thrust member 124 carried by slide 111 displaces an arm 131 (normally urged clockwise by a spring 133 on a pivot 122) to swing a hook 120 through the space between forked arms 118 and 119 to a position shown in broken lines where the thread (otherwise under tension between guides 106 and 116) is held to form a loop which is retained until the bobbin 109 starts to rotate whereupon the loop runs out thus permitting the winding of some turns with a gradual increase of tension which safeguards the thread from breakage. Alternatively. member 124 may pass between two forked arms on an eye-holder 115 to form a reserve loop of thread or a thread extension may be effected by a conventional catchthread device. The thread may be tensioried by a stream of air directed thereagainst. Alternative thread separation. The thread may be broken (optionally, over a sharp edge) by relative movement of two points at which it is temporarily gripped e.g. by clamping the thread itself or by securing the wound bobbin. As shown in Fig. 21, a full bobbin ejected into trough 10 is received in and slides down a tunnel 52 wherein it is held against a stop 53, during the changing operation, by a clamping member 54: thread F which has meanwhile been secured by spring 23 is severed, bobbin 13 is released, then thread end is released by centrifugal action of mass 24 to be incorporated in the wound package. In the machine of Fig. 22, thread F is held by a clamping member 61 in jaws 63, 64, while the rejected full bobbin lies free in trough 10.