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:
Jan. 19, 1988
Filed:
Aug. 21, 1985
Kiyoshi Inoue, Tokyo, JP;
Inoue-Japax Research Incorporated, Tokyo, JP;
Abstract
An EDM method and apparatus in which a succession of machining voltage pulses of regular polarity is applied from a first pulse supply between a tool electrode and a workpiece to produce erosive discharges across the EDM gap in the presence of a water flushing medium. A second pulse supply is also provided to apply one or more voltage pulses of reverse polarity during a time interval between successive machining voltage pulses of regular polarity across the EDM gap. A sensing circuit is provided to respond to a gap open-circuit condition and to provide an output signal representative thereof. The output signal is used to act on the second pulse supply so as to selectively trigger such one or more reverse-polarity pulses, or to temporarily modify the parameters of the reverse-polarity pulse or pulses, upon occurrence of the gap open-circuit condition.