Patent ID: 8168913

Claim:
An electric discharge machining (EDM) die sinking device comprising: a tank for holding a fluid; a first electrode fixed within the tank, the first fixed electrode immersed in the fluid, wherein the first fixed electrode includes a first shape for imparting a first mirror image shape to a first portion of a workpiece; a workpiece holder for positioning the workpiece at least partially immersed in the fluid and alternately moving the workpiece laterally between an inoperable position and a first operable position of the first fixed electrode at which electric discharge machining occurs on the first portion; a pulse generator for creating an electric discharge between the first portion and the first fixed electrode to remove material from the first portion in response to the workpiece being in the first operable position; and a second electrode in the tank, the second electrode having a second shape for imparting a second mirror image shape to a second portion of the workpiece, wherein the workpiece holder moves the workpiece laterally between the first operable position of the first fixed electrode at which electric discharge machining occurs on the first portion, the inoperable position, and a second operable position of the second electrode at which electric discharge machining occurs on the second portion, and wherein the pulse generator creates an electric discharge between the second portion and the second electrode to remove material from the second portion in response to the workpiece being in the second operable position.