Bowed shape electroforms

摘要

An electroforming process and apparatus for bowing the imaging surface to provide "steering" for moving the electroformed imaging surfaces over rollers or like devices. One embodiment of the present invention is to bow or crown the electroformed imaging surface by using a bimetallic mandrel. The outer material of the mandrel has a greater coefficient of expansion than the inner material. Thus, when the mandrel is heated the outer material expands more than the inner material creating the bowed or crown effect. The electroform takes on the bowed shape during plating and maintains that shape when removed from the mandrel. Another embodiment of the present invention involves mechanically or hydraulically bowing the mandrel and then plating the electroform on the bowed surface. This electroform also maintains the bowed shape when removed from the mandrel.