Hydromechanical deep drawing process - deforms blank into cup utilising hydraulic cushion between advancing punch and counter piston

摘要

The deep drawing machine uses an hydraulic cushion between an advancing die(7) and a counter-piston(3). The blank is clamped(9) over an opening in a die(10), the punch advancing axially through the opening to push the flan against the counter-piston. An indirect contact is made between the punch and the counter-piston, the applied force preventing leakage of the liquid cushion from between the blank and the piston face(13). An adjustable hydraulic force may be utilised, a peripheral seal(12) being mounted on the piston face, and a passage(6) connecting the face to a sec hydraulic cushion(4) at the fore of the piston. The passage and the sec cushion may incorporate a retention valve(5) and a pressure limiting valve(8) respectively.