DISPOSITIF A PERFORER

摘要

1314804 Punching UNIPUNCH PRODUCTS Inc 23 Dec 1971 [28 Dec 1970] 60123/71 Heading B3W A perforating device comprises a punch assembly 19 mounted in an upper arm 12 of a frame 11 -for movement towards a die 42 mounted in an opening 41 of a power arm 13 of the frame 11 so as to rest on a back-up member 51, which is accommodated in a recess 35 in the arm 13 and which has an aperture to allow the passage of a slug, produced in the perforating operation, into an ejection opening 48. The back-up member 51 of hard steel is removably secured to the frame 11 by a resilient split ring 60 which fits in counterbores in the aperture of the member 51 and ejection opening 48. The area of the die 42 engaging the back-up member 51 is less than that of the member 51 engaging the recess surface of the frame 11, which may be of plastics, cast iron, aluminium alloy or zinc alloy. The punch assembly 19 includes a slidable tubular guide 20 which is moved against the action of a spring 31 to engage a workpiece when a punch 26 is moved downwards by a press ram. Upon further downward movement of the press ram, a spring 30 between the punch head 29 and guide 20 is compressed causing the punch 26 to perforate the workpiece. When the ram is raised, the punch 26 is raised before the guide 20. More than one perforating device 10 may be positioned on the press. The device 10 includes positioning pins 61.