Patent GB-616587-A (GB)
Title: Improvements in or relating to methods and machines for tying knots
IPC: B65B13/26
Filed: 1946-09-13
Abstract: 616,587. Machines for tying knots. MARES, C. A. Sept. 13, 1946, No. 27607. [Class 94 (i)] In a method of forming a double-loop knot comprising wrapping a single thread around a pair of formers to produce loops lying side-by-side, twisting. the free ends of the loops together, placing one former above the other to superpose the loops and to make an overhand knot of the twisted ends, and drawing the ends of the loops apart to tighten the thread around a body and tie the overhand knot, the thread 13 is passed from a needle 10 which is reciprocated towards and away from a claw 12 so that on separation the thread is gripped between the jaws of claw 12. When the thread 13 is stitched from the jaw to the needle it lies in front of the former 14. Before forming the knot, the thread 13 is made to contact the former 14 by fingers 15, the former 14 being then rotated in an anti-clockwise direction, carrying with it the cam 16 engaged by a follower 17 carrying the fingers 15, which latter are thus moved towards and away from the thread 13. The former 14 is arranged to rotate alternately with the thread-feeding operation. It comprises a body 21, a pair of wings 22, hinged at 23 to the body, each wing 22 comprising a front plate 24 and a backplate 25 screwed to it and carrying four pins 27 passing through the front plate in certain circumstances and projecting therefrom. The front plate 24 of each wing is connected by a toggle linkage (not shown), within the shaft 19, with a rod 28 secured to a sleeve 29 which carries the linkage. The sleeve 29 carries a collar 30 separated from the frame 20 by a spring 31 so that the wings 22 are maintained against the body 21. Movement of the rod 28 to the left, and thus of sleeve 29, folds wings 22 about hinge 23. During the folding, ears 32 on the backplate 25 of the top wing bear against a stop 33 so that the backplate 25 is brought to rest, the continued movement of the front plate 24 releasing the pins 27 from it. Similar release occurs with the lower plate. After contact of thread 13 with the former 14, rotation of the former 14 through 360 degrees brings the thread into the position shown in Fig. 7. During the penultimate 45 degrees of rotation the follower 17 is disengaged by cam 16 to move the fingers 15 away, the ends of the thread returning to a position in front of the pins 27. In the final position (Fig. 7) the former 14 is held stationary while the rod 28 is actuated to fold the wings on to each other, the pins 27 being retracted. The loops are thus aligned between the front plates 24 around the holes 34 (as shown in Fig. 8). A loose tuft of hairs is passed through the holes 34 and the loop tightened around the tuft by lowering a pair of arms 35 to engage the thread 13, either by trip mechanism or manually, the thread being then not in tension. To lower the arms 35 mechanically, a carriage 36 is advanced towards the knot-former 14. On complete lowering of arms 35 advance of carriage 36 causes blades 37 to engage abutments 38 and to close on blades 39 to sever the thread 13. Worked-out details of a machine embodying the above mechanism are given in the Specification.