GB1282273A - Improvements in or relating to press tools - Google Patents

Abstract

1282273 Punches; strippers REDMAN ENG Ltd 8 Aug 1969 [31 May 1968] 26103/68 Heading B3W A punch for punching non-circular holes comprises a head 16, non-rotatably mounted in a holder 11 by engagement of a flat 17 with a plate 18 on the holder and of a screw 20 with a slot in the head part, a separate nose 13, means on or interposed between the parts for locating them relative to each other about the axis of reciprocation of the punch and means for clamping the head and nose together in any of a number of relative positions about said axis. As shown, the clamping means is a screw 21 and the locating means is a stepped collar 31 having two or more bores (one, 36, shown) therethrough radially aligned with a bore 32 in the head and a bore 34 in the nose. A single pin 37 may be located in bores 32, 36, 34. To vary the relative positions of the head and nose, the screw 21 is slackened, the nose is rotated relative to the head and is retained in the new position by two shorter pins, one passing through the bores 32 and 36 and the other passing through the bore 34 and the, or one of the, other bores in the collar. The die 39 has several bores 42 to receive a pin on the die holder 40 to allow the orientation of the die to be varied to correspond with that of the punch nose. Instead of the locating pins the collar may have serrated surfaces for engaging serrated surfaces on the lower surface of the head and the upper surface of the hose. The collar may be omitted, serrated surfaces on the head and nose mating with each other. A stripper 14 is biased by spring 29 mounted between a hardened insert 28 and a flange 30 on the stripper, a weaker lifter spring 15 also being provided.