BigPatents India

There is provided an attachment for a spark erosion machine having a working head, the attachment including a top part fixedly attachable to the working head, a body suspended from, and moveable relative to, the top part with one degree of freedom in translation, a guide for guiding the body in the translational movement and a main shaft mounted in the body and rotatable about an axis parallel to the translational movement. There is also provided a driver for imparting the main shaft a rotational movement, a drive pin having an axis parallel to the axis of the main shaft and rotatably connected thereto by an adjustable connector adapted to connect the drive pin to the main shaft in a plurality of positions between a first limit position of coaxiality and a second limit position of maximal eccentricity relative to the main shaft. The attachment also includes an electrode holder associated with the drive pin, and coupler connected to the electrode holder for resolving the rotary movement of the drive pin, when in an axially eccentric position, into an electrode movement in a compound XY-direction only, producing an orbital movement of an electrode mounted in the electrode holder.