Back pressure device for progressive die apparatus and progressive die apparatus provided therewith

Abstract

In a back pressure device for progressive die apparatus, a suitable back pressure can be produced during the blanking interval preventing the iron core laminates from being pushed upward by using a simple structure. The back pressure device for progressive die apparatus comprises a support table (31) disposed in a vertically moveable manner in an iron core retaining member (22) for retaining iron core laminates blanked from the sheet steel strip in the progressive die apparatus (1) and for stacking the iron core laminates thereon one after another, a support unit (32) for supporting the support table, a lifting motor (33) for causing a vertical movement of the support table via the support unit and a control unit (34) for controlling a rotational motion of the lifting motor, wherein the control unit is configured to set a plurality of torque limit values for limiting an output torque of the lifting motor depending on an action of the progressive die apparatus so that the output torque is limited by a largest of the torque limit values during a blanking interval for the iron core laminates.

Dependencies are inferred from the claim text.