New or Improved Means for Punching and Countersinking Holes Simultaneously in Metallic Plates.

摘要

13,597. Scott, H. D., and Cartmell, H. June 27. Punching; shearing.-A punching - machine is provided with cutters for countersinking the holes simultaneously with the punching. The enlarged portion b of the punch has clamped to it a yoke c on which cutters d are mounted. The forked flange e1 of a bracket e engages the cutters and presses them towards the punch, their semicircular ends cutting out the countersink and finally enclosing the punch. Projections d1 on the cutters prevent them from moving outwards too far, and a forked bracket g moves the cutters outwards as the punch rises.