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. 12, 1994
Filed:
Mar. 09, 1993
Applicant:
Inventors:
Chuen-Cheng Fu, Roanoke, VA (US);
Warren T Lay, Roanoke, VA (US);
Assignee:
Ingersoll-Rand Company, Woodcliff Lake, NJ (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
175296 ; 166319 ;
Abstract
A pressure sensitive valve for a fluid-actuated percussive drill includes passageways for fluid flow to expose a valve surface to a burst of short-interval, high pressure fluid from a drive chamber to cause early closing of the valve.