Coupling adapter

A coupling adapter for coupling a chuck of a machine tool, such as an electrical discharge machine, with a tool so as to precisely and repetitively position the tool with respect to the chuck, said machine tool including a pressure medium source and central control system for controlling the pressure medium from the pressure medium source, said chuck including chuck face coupling elements extending from a face of said chuck, said tool including a tool anchor and tool face coupling elements extending from a face of said tool, wherein said coupling adapter includes a first end face having coupling adapter first coupling elements that are engageable with said chuck face coupling elements to define a first holding system for holding said coupling adapter in a predetermined reference plane with respect to said chuck and along a predetermined axial direction perpendicular to said reference plane, said coupling adapter further including a second end face having coupling adapter second coupling elements that are engageable with said tool face coupling elements to define a second holding system for holding said tool in a predetermined reference plane with respect to said coupling adapter and along a predetermined axial direction perpendicular to said reference plane, said coupling adapter further including a tool holding mechanism for retaining said tool anchor, said tool holding mechanism in pressure medium communication with said pressure medium source through a pressure medium channel that extends through said chuck and said coupling adapter.