Hydraulic deep drawing apparatus

摘要

A hydraulic deep drawing apparatus for a press for drawing shaped sheet metal parts from a workpiece. The apparatus comprises hydraulic pressure cylinders, a sheet holding plate supported by the hydraulic pressure cylinders and onto which the workpiece is laid, a tool baseplate arranged under the sheet holding plate, a ram which moves vertically toward the workpiece until just before contact with the workpiece, and which is fixed to a frame of the press at a gap DELTA s from the workpiece, and a multipoint unit having plural short stroke cylinders arranged according to a drawing ring contour, the short stroke cylinders being hydraulically actuated to bridge the gap DELTA s and press the workpiece against a drawing ring. A holding force for deep drawing the workpiece comprises an outer effect ring and an inner effect ring. The outer effect ring is loaded by sheet holding cylinders, and the inner effect ring is loaded by pressure pins and shaping pins.