IMPROVEMENTS IN PUNCHING PRESSES

摘要

1,253,557. Punching; strippers. C. BEHRENS A.G. 19 Feb., 1969 [24 Feb., 1968], No. 8899/69. Heading B3W. In a crank-operated punch press the crankshaft 4 also actuates a stripper and hold-down mechanism through cams 15 and energyabsorbing resilient means 28 which during a punching operation are compressed after the stripper etc. mechanism has contacted a workpiece. The stripper mechanism comprises a disc 8 supporting a stripper 14 and connected to guides 22, springs 12 maintaining the disc in its rest position against the underside of the punch carrier 1, which as shown is a rotary multiple punch carrier. Each cam 15 bears on a follower roller 35 supported by a forked pin 36 which is mounted in a yoke 37 and includes a shank 361 which is slidable in a bush 38. The bushes 38 form part of a ram casing 39 which also supports the crank-shaft 4. Spaced from the yokes 37 by means of bolts 13 is a frame 40 and located between the yoke and the frame are the resilient means 28 in the form of rubber springs 11. During a punching operation the cams 15 cause the frame 40 to move downwardly ahead of the ram 7 and apply thrust to the stripper disc 8 through pillars 22 until the stripper 14 contacts a workpiece. Further downward movement causes the springs 11 to be compressed. During the upward stroke of the press the cams 15 cause the pressure to be removed from the springs 11 to allow the springs 12 to raise the disc 8 only after the ram 7 has raised the punch 5. Reference has been directed by the Comptroller to Specification 950,807.