GB1172763A - Improvements in or relating to Punching Machines. - Google Patents

Abstract

1,172,763. Punching. N. DOLBERG. 15 April, 1967, No. ]7408/67. Heading B3W. A machine for multiple side punching a tubular blank supported on a mandrel 38, has blank ejecting device 16 and a plurality of angularly spaced punching units, each including a tool 56 connected to a ram 70 which is radially movable by a connecting cam 78, 80, 82, 84 supported and arcuately moved by a rotatable annular carrier 36 surrounding the punching units. In one embodiment, the machine is operated by a start switch (182), (Fig. 7, not shown), which energizes a solenoid valve (158) to cause extension of a piston-rod 102 which rotates the carrier 36. As the carrier 36 rotates, spherical cam followers 88 mounted on the ends of the rams 70 are moved along elongate slots 86 in the cam elements 78, 80, 82, 84 to cause the rams 70 and punches 56 of each punching unit to be moved radially inwards. The innermost radial position is reached when the rams 70 are perpendicular to the cams, further rotation of the carrier 36 in the same direction causing the rams 70 to move radially outwards to the position of Fig. 6. In this position, a switch 188 is actuated by an actuator 190 on the piston-rod 102 to energize a solenoid valve (168) which causes extension of ejector pins 136 connected to a ram plate 135 of a piston-rod 140, the pins 136 passing through elongate slots in the side wall of the mandrel 38. The ejector pins 136 are returned to their initial position by an actuator 194 closing a switch 192 which actuates the valve (168). When the start switch (182) is again depressed, the punching cycle is repeated with the carrier 36 rotating clockwise. When a greater number of rows of holes or indentations are to be punched, cams half the length of cams 78-84 are used, extension and retraction of the piston-rod 102 performing one complete punching cycle.