Blank holding down device for metal forming press - has four hydraulic cylinders with pressure controlled by pressure regulator

摘要

A single stroke press for deep drawing sheet metal has a hydraulic device for holding the blank (4) during the deep drawing operation. The device consists of at least four hydraulic cylinders (10) with pistons (9) which act on a beam (8) which in turn acts on rods (7) which press the blank holder (4) upwards against the blank (3) and against the upper tool (2). The pressure chamber (13) of each hydraulic cylinder is connected to a source (19) of pressure medium through a pressure regulator (23). During the deep drawing operation the fluid outflow, from the part of the cylinder not connected to the pressure regulator, is prevented. USE/ADVANTAGE - Blank holding device with means to prevent excessive force being exerted on the blank.