GB1338887A - Punch press with an adjustable stripper and punch stroke control - Google Patents

Abstract

1338887 Controlling punches; strippers W A WHITNEY CORP 4 July 1972 [2 Aug 1971] 31194/72 Heading B3W A fluid-actuated press includes a punch ram, a stripper vertically adjustable relative to an underlying die to accommodate workpieces of different thicknesses and means on the stripper, and adjustable with it, for detecting the arrival of the lower end of the punch a predetermined height above the lower end of the stripper, at whatever height the stripper may be, and producing a signal to end the upstroke of the ram. A stripper housing 29 is adjustably mounted on a first press member 13 by means of a drum 53 in threaded engagement with a collar 59 on the housing and a sleeve 34 depending from the member 13. The drum 53 carries a spurgear 49 which is rotatable by a motor-driven gear 65 to cause the drum to be threaded up or down on the sleeve 54 and the collar 59 to thread up or down within the drum, the stripper housing thus moving twice the vertical distance that the drum moves. A rod (63), Fig. 3 (not shown), depending from the sleeve 54 extends through a slot (64) in the collar 59 to prevent angular movement of the stripper housing relative to the sleeve. A detector (70), Fig. 3, fixed to the stripper housing is triggered by a member (71) on the punch ram 27 when the lower end of the punch 14 is just above the lower end of the stripper plate 30 to signal a solenoid-controlled valve (25), Fig. 4 (not shown), to stop the supply of fluid to the lower end of the ram cylinder 21. A second detector 31 mounted on a bracket 32 depending from the press member 13 extends through the stripper housing and is triggered by a member 36 on the ram when the punch has travelled a predetermined distance into the die (15), Fig. 1 (not shown), to signal the valve (25) to switch fluid supply from the upper to the lower end of the ram cylinder 21. The housing 29 has an open side for insertion of different punches and strippers.