GB1072747A - Improvements in high energy impact machines - Google Patents

Abstract

1,072,747. Metal working hammers. U.S. INDUSTRIES Inc. April 1, 1965 [April 1, 1964], No. 13866/65. Heading B3H. A high energy impact machine has a pair of plates 3, 4 movable together by high pressure gas stored in a chamber 10, the plate 3 having a cylinder 9 containing a sealing piston 16 connected to the other plate 4 and adapted to seal off the chamber 10 from the cylinder, and means 40, 34 for admitting gas from the chamber 10 beneath the piston 16 to lift it from its seating and thus initiate the working stroke. Each plate 3, 4 is slidable in guides 5, 6 and carries co-operating dies 63, 64, Fig. 1 (not shown) for forming a metal workpiece. The chamber 10 is provided within plate 3 by transverse passages 11-14, Figs. 2, 3 (not shown) interconnected at their ends with openings 15 leading into a pair of working cylinders 7, 8 containing hollow pistons and rods 16, 17 connected at 21, Fig. 1 (not shown), with the lower plate 4. Pressure nitrogen from a source 27 is admitted through valves 26, 49 to the chamber 10 and to cylinders 9 above the pistons 16. Charging pistons 60 within the cylinders are then moved downwardly by hydraulic pressure admitted through passages 68, to pressurize the gas in the cylinders and in the chamber 10 and to press the pistons 16 against seatings 18 at the lower ends of the cylinders. The hydraulic pressure is then reduced whereby the charging pistons 60 are retracted by gas pressure in the cylinders 9 acting through the hollow pistons 16. Trigger valve 40 is then opened by a hydraulic actuator 41, Fig. 4 (not shown), to admit high pressure gas from chamber 10 into chambers 19 below the pistons 16, Fig. 6 (not shown). The pistons 16 are thus raised from their seatings and allow the high pressure gas in chamber 10 to act quickly through passages 15 whereby the plates 3, 4 are accelerated towards each other. Recharging is effected by opening the valve 49 which is actuated by a hydraulic motor. The valve 49 may be omitted. The upper plate 3 is retracted by two counterbalance units 56, Fig. 1 (not shown), charged with pressure gas. An electrical control system is described, Figs. 9, 10 (not shown) for the valves 40, 49 and for the supply of gas and hydraulic fluid. A specific example is given of the energy produced by the machine.