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:
Apr. 04, 1989
Filed:
Mar. 21, 1988
Gary F Rupert, Ann Arbor, MI (US);
Raycon Corporation, Ann Arbor, MI (US);
Abstract
A process for drilling chamfered holes includes the steps of directing noncontact energy onto the outer surface of the part to form a recessed crater-like entrance with chamfered walls and thereafter directing a small diameter wire electrode adjacent the substrate and spark eroding the base without removing material from the chamfered walls so as to produce a combined passage through the part with a chamfered entrance leading to a smaller outlet. In one embodiment the part has a ceramic coating which is initially removed from the part by either focusing a laser beam to a penetration depth which removes the ceramic coating while forming the entrance and in another embodiment the coating is initially removed by imposing a high voltage pulse thereagainst from a spark erosion electrode of electrical discharge machining equipment.