The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 19, 1989
Filed:
Feb. 02, 1988
Jean-Claude Diot, Douvaine, FR;
Roger Girardin, Vernier, CH;
Charmilles Technologies S.A., Meyrin, CH;
Abstract
A device for machining by electroerosion has a tool electrode driven in a rotary motion controlled by a servomotor and showing the shape of a solid of revolution around its axis of rotation. A measuring circuit continuously evaluates the degree of contamination of the machining dielectric liquid in relation to a reference value. The measurement is made by a transducer for the instantaneous voltage U.sub.i of each spark and by comparing it to a predetermined value U.sub.b, thus determining the proportion of so-called low-level sparks for which U.sub.i .ltoreq.U.sub.b, a signal being delivered when this proportion surpasses a predetermined threshold, or by a current transductor working during the waiting time preceding the striking of each spark, a signal being delivered when a predetermined current threshold is attained. A servo circuit modulates the rotation speed of the tool electrode as a function of this signal. The detector makes it possible to detect and remedy the appearance of ejected sparks.