公开(公告)号：EP0695225A1

公开(公告)日：1996-02-07

申请号：EP94913229.0

申请日：1994-04-11

申请人： AP & T TRANEMO AB

发明人： WALKIN, Bengt

IPC分类号： B21D24

CPC分类号： B21D24/14

摘要： A hydraulic press for deep drawing has mutually reciprocating clamping rings (6, 13) for fixedly clamping a sheet metal blank (5) with a predetermined force. The clamping rings (6, 13) are operated each by their cylinder (9, 14). The press has a tool (4) for forming the sheet blank (5), and a power unit (10, 11, 16) for generating a relative movement between, on the one hand, the clamping rings (6, 13) and, on the other hand, the tool (4). During the forming phase, the working volumes of the cylinders (9, 14) are interconnected to a common volume to which there is further connected a pressure maintenance device with a pressure sensor (22), a regulator valve (23) and a pump (28). The piston areas of the cylinders (9, 14) are suitably equal.