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:
Nov. 07, 1989
Filed:
Jul. 15, 1988
Jo-Yu Chuang, Sugarland, TX (US);
Sandvik Rock Tools, Inc., Bristol, VA (US);
Abstract
A down-hole percussion drilling tool supplied with compressed air includes a piston reciprocated in an enclosed cylinder against a bit. A spool is continuously reciprocated in a valve chamber by a pilot fluid pressure supply, tapped from the compressed air from a major air flow passage to either a first or a second feed passage. Compressed air conducted through the first feed passage accelerates the piston toward the bit and compressed air conducted through the second feed passage accelerates the piston away from the bit. The continuous reciprocation of the spool is independent of the position of the piston relative to the cylinder.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile