Hydraulic control for die pads in presses

Claim 1

IN A CRANK TYPE PRESS HAVING A RAM AND A MOVABLE DIE AND IN WHICH THE DIE IS CONTACTED BY THE RAM DURING THAT PORTION OF ITS STROKE IN WHICH IS VELOCITY IS RELATIVELY HIGH AND IS DECELERATING, AND A HYDRAULIC CUSHION FOR THE DIE INCLUDING A HYDRAULIC CYLINDER HAVING A PISTON THEREIN REACTING AGAINST SAID DIE, A TANK OF HYDRAULIC FLUID UNDER RELATIVELY LOW PRESSURE, A HYDRAULIC CONNECTION BETWEEN SAID TANK AND SAID CYLINDER FOR SUPPLYING HYDRAULIC FLUID UNDER TANK PRESSURE TO SAID CYLINDER TO BIAS SAID DIE TO ITS EXTENDED POSITION, MEANS PREVENTING RETURN FLOW THROUGH SAID CONNECTION, A SECOND HYRAULIC CONNECTION BETWEEN SAID TANK AND CYLINDER THROUGH WHICH HYDRAULIC FLUID FLOWS FROM SAID CYLINDER TO SAID TANK AS SAID DIE IS RETRACTED UPON CLOSING OF THE PRESS, A PRESSURE RELIEF VALVE IN SAID SECOND CONNECTION TO PROVIDE A PREDETERMINED RESISTANCE TO DISPLACEMENT OF HYDRAULIC FLUID FROM SAID CYLINDER UPON CLOSING OF THE PRESS, A HYDRAULIC SHOCK ABSORBER COMMUNICATING DIRECTLY WITH SAID CYLINDER TO ALLOW DISPLACEMENT OF HYDRAULIC FLUID FROM SAID CYLINDER INTO SAID SHOCK ABSORBER PRIOR TO OPENING OF SAID PRESSURE RELIEF VALVE TO REDUCE SHOCK IN SAID CONNECTION CAUSED BY THE IMPACT OF THE RAM ON THE DIE AT SAID HIGH VELOCITY, AND A HYDRAULIC SHOCK ABSORBER IN SAID FIRST CONNECTION INTO WHICH HYDRAULIC FLUID FLOWING FROM SAID TANK TO SAID CYLINDER UPON OPENING OF THE PRESS MAY BE DISCHARGED TO REDUCE THE SHOCK IN SAID CONNECTIONS CAUSED BY THE MOMENTUM OF THE HYDRAULIC FLUID FLOWING THROUGH SAID FIRST CONNECTION AND THE ABRUPT STOPPAGE OF FLOW OF FLUID WHEN SAID DIE REACHES ITS FULLY EXTENDED POSITION.