Method of making a high torque battery terminal

摘要

A battery terminal with high torque resistance utilizing three sided frusto-conical recesses and mating protrusions extending from the battery terminal and method of making the terminal by a cold forming process that forms a finished battery terminal from a preworked lead slug by driving one end of a punch through the slug to remove excess material and form an axial through hole, a second and third portion of the punch to close the die chamber and a fourth portion of the punch to radially expand the lead slug into a finished battery terminal. The dies for forming the battery terminal include a movable multiple-segmented die for collapsing radially inward around the slug and a frusto-conical die for forming the top portion of the battery terminal. An ejector sleeve removes the finished battery terminal after the cold forming process. A cylindrical punch with a transition zone that minimizes the local pressures in the die while elongated vent passages allow air to escape from the die to minimize formation of irregular terminals.