Abstract: The invention relates to a method and device for electrical Wire electrical discharge machining method (WEDM) for forming a desired pattern on a workpiece by a WEDM machine tool, in which a preliminary voltage pulse is applied to a gap between a wire electrode and a workpiece, and in which, at the breakdown of said preliminary voltage pulse, a first machining discharge pulse is applied to the wire electrode.

Abstract: A method for controlling a wire electric discharge machine comprising the steps of: determining of at least one predefined contour deviation (Esmax) of a predefined contour to be cut into the workpiece; determining a curvature of at least one geometry element defining at least one section of the contour to be cut into the workpiece; calculating a displacement (s) of an upper guide (WGU) and a lower wire guide (WGL) based on the predefined contour deviation (Esmax) and on the curvature of the at least one predefined geometry element; and setting the displacement (s) by moving the upper guide (WGU) relative to the lower wire guide (WGL) such that the wire electrode guided by the upper (WGU) and lower wire guides (WGL) is inclined in a current cutting direction of the workpiece during cutting of the geometry element into the workpiece.

Abstract: A method for controlling a wire electric discharge machine comprising the steps of: determining of at least one predefined contour deviation (Esmax) of a predefined contour to be cut into the workpiece; determining a curvature of at least one geometry element defining at least one section of the contour to be cut into the workpiece; calculating a displacement (s) of an upper guide (WGU) and a lower wire guide (WGL) based on the predefined contour deviation (Esmax) and on the curvature of the at least one predefined geometry element; and setting the displacement (s) by moving the upper guide (WGU) relative to the lower wire guide (WGL) such that the wire electrode guided by the upper (WGU) and lower wire guides (WGL) is inclined in a current cutting direction of the workpiece during cutting of the geometry element into the workpiece.

Abstract: A method of and a spark erosion apparatus for fine machining by spark erosion of a workpiece (2) with a wire electrode (1) eliminates very efficiently process interruptions caused by short circuits, such that at least one gap parameter is continuously monitored for the purpose of detecting a short circuit; when a short circuit is detected, the forward motion of the electrode (1) is arrested at the point (K) where the short circuit occurred; if the short circuit persists, the electrode (1) is moved away from the workpiece (2) to an intervention point (M)--in a direction perpendicular to the path (6) used for trim cutting; at the intervention point (M), one or several measures to eliminate the short circuit are executed once or several times; and after it has been detected that the short circuit is eliminated, the electrode (1) is moved back to the point (K) where the short circuit occurred, whereafter normal machining continues.

Abstract: A method of precision electric-discharge machining carried out in apparatus of moderately high precision and stability with an electrode in the form of a wire. The object is a surface as smooth as the surface that can be obtained with the more expensive very high-precision apparatus. The contour of work that has already been roughed out at least once is accordingly exploited as a geometrical reference for at least one finishing cut. The gap is maintained constant by fine adjustments.