Method for die forming strip material

Abstract

A pair of mating die halves are employed to die form an elongate strip or ribbon composed of material capable of undergoing plastic deformation. The first die half is an elongate, substantially rigid member having a die face of predetermined configuration. The second die half is an elongate, flexible die member having a die face of configuration complementary to the die face of the rigid die half. The die face of the rigid die half is fed into registering relationship along a substantially straight path with the die face of the flexible die half. The flexible die half is fed toward the rigid die half along an arcuate path until it registers with the rigid die half, after which it is fed along a straight path parallel to that of the rigid die half. The elongate ribbon to be formed is fed between the die halves as the latter are fed into registration. The die halves are fed into a pressure forming chamber which applies mutually opposing forces to the rigid and flexible die halves causing a portion of the strip of material situated between the die faces to undergo plastic deformation. The die halves and ribbon are intermittently fed into and stopped in the pressure forming chamber. A pressure sufficient to cause the ribbon to undergo deformation is applied to the die halves while they are stopped in the pressure chamber. As a predetermined length of the elongate die members and strip of material is fed into the pressure chamber, the same length of strip of material and accompanying die halves is simultaneously withdrawn from the pressure chamber. Downstream of the pressure chamber the flexible die half is separated from the rigid die half to free the formed strip. Thereafter the strip can be severed into desired lengths.