Patent ID: 8601849
Filing Date: 2013-12-10
Classification: B21D,B21J,H05K,Y10T

Abstract:
1. A method for fabricating a device cover, the method comprising: providing a metallic sheet; drawing the metallic sheet into a preformed cover having a bottom base and at least one sidewall extending from the bottom base, wherein the at least one sidewall comprises a contact surface; upsetting the preformed cover by a forming die to thicken the at least one sidewall, wherein the forming die comprises a punch; the punch moves along an axis of the at least one sidewall relative to the preformed cover; the punch comprises a working surface; an angle defined by an axis of the at least one sidewall relative to at least one of the contact surface of the sidewalls and the working surface of the punch is about 55° to about 65°; machining the at least one sidewall of the preformed cover to form the device cover; wherein the forming die comprises a lower die assembly and an upper die assembly, and the lower die assembly includes a die set, a die holder, and a die core movably connected to the die set, a supporting plate and a nitrogen spring; and wherein the die set is fixed to the supporting plate, one end of the nitrogen spring is connected to the supporting plate, and the other end of the nitrogen spring is connected to the die core.