Patent GB-1460678-A (GB)
Title: Apparatus for removing coupling elements from preselected zones of a continuous coupled slide fastener forming strip
IPC: A44B19/58
Filed: 1974-08-12
Abstract: 1460678 Shearing DR ING JOSEF RUHRMANN KG 12 Aug 1974 [7 Sept 1973] 35520/74 Heading B3W [Also in Division E2] Apparatus, for removing coupling elements 94 from preselected zones 97 of a continuous, coupled, slide fastener forming strip 9 having coupling elements formed by two continuous filaments 93 secured each to a respective carrier tape 91, comprises drive means 70, 71 for continuously moving the strip along a feed path through the apparatus, a cutting disc 40 and a co-operating contra-rotatable wheel 50, the cutting disc having a cutting segment 41 projecting radially of the disc over part of its periphery for cutting off parts of the coupling elements that project beyond the edges 95 of the carrier tapes 91, and a plurality of recesses 42 in the cutting segment 41 open at their axial and radially outer extremities, the recesses being each for accommodating those parts of a coupled pair of coupling elements that project beyond the edges of the carrier tapes, having a pitch distance corresponding to two pairs of coupling elements, and being each separated from the next adjacent recesses by the distance spanned by one coupled pair of coupling elements so that a cutting tooth 44 for severing a pair of coupling elements is formed between each adjacent pair of recesses. According to the invention also a circumferential groove 51 in the contra-rotatable wheel 50 is adapted to receive a part of each of the cutting teeth, severed portions of the coupling members being pushed into the circumferential groove by the cutting segment, and means for removing the remnants of the severed coupling elements from the carrier tapes. As shown, the apparatus comprises a tape draw-off roll 70 and a pressure roll 71 at a driving station 7 to draw off successively past a feeler roller 20, with a limit switch 21 which controls the drive of the machine which is actuated whenever the roller 20 falls off the end of the tape, a tapetensioning brake 25, a strip measuring drum 32 for measuring the length between gaps, and a cutting station 4 comprising the cutting disc 40 and the co-operating wheel 50, pressure applying elements 60, 62, and a tape-direction-changing roller 67. The wheel 50 has, over part of its length, two transversely aligned rows of teeth 55 the pitch of which corresponds to the distance between next adjacent coupling elements. In use, a length of strip 9, as selected by the measuring drum 32, is fed through the gap between the cutting disc 40 and the wheel 50 both of which are stationary in the position shown in Fig. 5, a cutting operation being initiated by the measuring drum 32, a switch 31, an electro-magnet 34, and a single-revolution clutch, not shown, to rotate the cutting disc 40 and the wheel 50 in opposite directions. As the teeth 55 on the wheel 50 meet the strip 9 the limbs 96 of the adjacent coupling elements are pushed, by an element 60, into the grooves between the teeth 55, the cutting element 41, as it rotates past the wheel 50 receiving, preferably with a tight fit, each second pair 98 of coupling elements in the grooves 42 and the intermediate pair of coupling elements 98 being severed by the cutting teeth 44 in the zone between the edges 95 of the tapes 91, Fig. 9. The severed parts 99<SP>1</SP> are separated by a wedge 64, pressed further into the groove 54, and then removed from the latter by a stripping device 58. After completion of the cutting operation remnants 98, Fig. 9, of the coupling elements still remain in the recesses 42, and when the leading end of the cutting segment 41 abuts a tip 63 on the pressure applying element 62 the tape-directionchanging roller 67 is moved from its upper, Fig. 5, to its lower, Fig. 4, position and the element 62 is raised into contact with the tape 9 so that the strip 9 is moved away from the cutting disc over the pressure plate 62 which maintains the remnants 98 in the recesses 42 as the remnants are drawn from the loops 92 of the stitching securing them to the tapes 9. Stripping devices 48, 58 respectively remove the remnants and the severed parts from the recesses 42 and the groove 54 as the cutting disc 40 and wheel 50 continue their rotations. The continuous filaments 93 are preferably made of plastics material.