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. 03, 1995
Filed:
Nov. 18, 1993
Thomas J Stobbs, Brookfield, WI (US);
James R Ward, Milwaukee, WI (US);
Applied Power Inc., Butler, WI (US);
Abstract
A hydraulic pressure reducing and relieving valve has a body with input, control and relief ports, a tubular spool slidably received within the body for selectively providing communication between the ports, and a tubular quill within the spool which the spool can slide over. The quill has a lumen which provides communication from one end of the spool to the other, so as to pressure balance the spool with relief pressure, and together with the spool defines a feedback chamber in communication with the control port which generates a force on the spool which opposes the operating force exerted on the spool by a solenoid. The spool may also be biased by a spring in the feedback chamber.