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. 12, 1985
Filed:
Jul. 25, 1984
James R Mayer, Englewood, CO (US);
Other;
Abstract
A pilot pressure fluid operated spool type power fluid distributing valve for operating a hydraulically powered reciprocating piston pump includes a spool closure member with opposed unequal diameter bores formed in the spool ends. Pilot actuator pistons project into the bores and include pilot pressure fluid passages opening into the bores from sources of pilot control fluid. The bore of smaller diameter includes an enlarged annular chamber which may be closed by a cooperating ridge on the associated piston and a reentrant edge of the bore so that the closure member may be biased in one position if already in that position until a predetermined pilot fluid pressure is present in the opposite bore.