Patent GB-1041544-A (GB)
Title: Machine for the manufacture of sliding clasp fasteners
IPC: B21D53/50
Filed: 1963-06-10
Abstract: 1,041,544. Making sliding clasp fasteners. K. F. N€GELE. June 10, 1963, No. 23027/63. Heading B3A. [Also in Divisions E2 and F2] A machine for the manufacture of sliding clasp fasteners in which rows of coupling members each of a predetermined length are secured to a long length of stringer tape and gaps devoid of members each also of a predetermined length are provided between the rows comprises a control device for determining the fastener length and the gap length, the mechanism for securing the coupling members being controlled by the control device which in use stops and starts the said mechanism, the control device being connected to the driving shaft of said mechanism and comprising a control nut 10, movable on a screw threaded shaft 9 to and fro between two end positions, through a reversing mechanism, by a connecting shaft 3 coupled to said driving shaft, which in use is continuously driven, the said control nut carrying two cams 15, 16 by means of which an electrical or mechanical reversal of the reversing mechanism is effected, the distance between said cams being adjustable to enable the length of the rows to be determined and a cam disc 19 carried by the control nut for stopping the securing mechanism to provide the gaps devoid of members. In the construction shown the cam 16 and the cam disc 19 are carried by a control ring 12 which is adjustable on a screw thread of the nut relative to a flange 10a which carries the other cam 15, one revolution of the nut relative to the flange 10a giving a coarse adjustment of the fastener length which is indicated by a scale on a bar 10c which carries switches 17 and 18 operated by the cams 15 and 16 respectively. The rotational position of the cam 16 with respect to the cam 15 gives a fine adjustment of the fastener length and a spring-loaded plunger carried by the control ring is engageable with a desired one of a number of recesses in the nut 10 to locate the ring. The reversing mechanism comprises a bevel gear 7 which is connected to the flange 10a of the nut by means of rods 11 which slide in holes in the flange, two bevel gears 5 and 6 which alternately drive the bevel gear 7 and a slidable coupling sleeve 4a which connects the bevel gears 5 and 6 alternately to the connecting shaft 3 and which is moved between its positions by a pair of solenoid coils 4. The solenoid coils are energized alternately by the switches 17 and 18 the switches being actuated in turn at each limit of travel of the nut by the cams 15 and 16. The cam disc 19 is adjustable relative to the cam 16 so that the length of the gap between rows is adjustable. The cam disc actuates a lever 21 which is coupled to the securing mechanism to prevent its operation when the lever is on a surface 22 of the cam disc. In a modification instead of providing an electromagnetically operated reversing mechanism the cams 15 and 16 move the sleeve 4a mechanically through a lever. To increase the changeover speed of the reversing mechanism two permanent magnets are provided one on a lever connected to the sleeve 4a and the other on a casing; the magnets are positioned in such a way that in the central position of the lever they repel each other and in its two angular positions in which the sleeve is driving one or other of the bevel gears 5 and 6 they attract each other. In a modification a second cam disc can be provided at the opposite end of the control nut to the cam disc 19.