Patent ID: 7919721

Claim:
A method of measuring a taper angle in a wire electric discharge machining apparatus comprising, the steps of: providing a measuring tool having lower and upper edges being spaced by a given height; aligning a wire electrode vertically between a pair of wire guides; moving the vertical wire electrode from a reference position in one direction by a first distance until contact between the wire electrode and the lower edge is detected; moving the vertical wire electrode from the reference position in the one direction by a second distance until contact between the wire electrode and the upper edge is detected; inclining the wire electrode at a taper angle; moving the inclined wire electrode from the reference position in the one direction by a third distance until contact between the wire electrode and the lower edge is detected; moving the inclined wire electrode from the reference position in the one direction by a fourth distance until contact between the wire electrode and the upper edge is detected; and calculating the taper angle based on the first, second, third and fourth distances and the given height.