Abstract: In a travelling wire EDM apparatus, a unitary assembly of at least one of the electrode wire support members and a machining fluid nozzle disposed coaxially to the wire is installed on a plate which is displaceable such as to provide the electrode wire passing through the machining zone in the workpiece with an appropriate inclination. Inclination of the unitary assembly of the electrode wire support member and machining fluid nozzle is obtained by a swivel member mounted on the plate and oriented by a tube through which the electrode wire is passed. The tube is supported along its length by a pivot which is at all times disposed symmetrically to the electrode wire lower support member relative to a plane of symmetry. The unitary assembly is also supported by a swivel joint member interconnected to the first swivel joint member such that the angular displacement of the respective swivel joint members are symmetrical.

Abstract: An EDM process and apparatus capable of transversely displacing the electrode tool relative to the electrode workpiece according to a translation motion, while simultaneously linearly advancing the electrode tool relative to the electrode workpiece along a longitudinal axis. The process and apparatus of the invention consist in monitoring a machining dimension and comparing it to a predetermined parameter, and, as soon as such predetermined dimension parameter is achieved, sequentially retracting the electrode tool and re-establishing the feed of the electrode tool, while changing the radial direction of electrode translation motion between the beginning of the electrode tool retraction and the end of the electrode tool feed.