Abstract: An apparatus for electrical discharge machining (EDM) is disclosed having a housing and a workpiece support assembly secured to the housing for holding a workpiece in a predetermined location. An EDM electrode is attached to the housing for performing the EDM machining. A tank assembly is also attached to the housing and movable between a machining position and a retracted position. In the machining position, the tank assembly encompasses a workpiece secured to the workpiece support area and filled with a dielectric fluid necessary for the EDM machining process. In its retracted position, the tank assembly is spaced away from the workpiece to facilitate access to the workpiece for removal of the finished workpiece and reattachment of a new workpiece in preparation for the next EDM machining operation.

Abstract: An electrical discharge machine including a base frame having secured thereon a workpiece holding fixture and an upright frame member, a support member slidably mounted on the upright frame member, either one or two turrets indexably mounted on the support member, and a plurality of equally spaced electrode cartridge assemblies removably mounted on each turret. Each cartridge assembly includes an electrode guide and one or more electrodes extending through the electrode guide to a position just above a workpiece. A suitable drive unit moves the support member and turret and, hence, the cartridge assembly and electrodes toward and away from the workpieces to spark erode desired openings therein.

Abstract: Apparatus and a method are provided to form the interior of a fuel injector spray tip by use of a cold forming punch to form a V-shaped spray tip interior configured to reduce fuel dribble and thereafter finishing the interior by use of an EDM electrode to form precision valve seat and fuel sack surfaces.