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:
Dec. 22, 1987
Filed:
Nov. 18, 1985
Applicant:
Inventors:
Dennis R Barber, Waterloo, IA (US);
Larry M Delfs, Cedar Falls, IA (US);
Ronnie F Burk, Waterloo, IA (US);
Assignee:
Deere & Company, Moline, IL (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F15B / ; F16K / ;
U.S. Cl.
CPC ...
60403 ; 60459 ; 91421 ; 91426 ;
Abstract
A hydraulic motor has its lube drain connected to the motor return line. A motor seal protector valve has a pilot which responds to pressure in the motor return line. Normally, the valve connects system pressure to the motor inlet. High pressure in the return line causes the pilot to move the valve to block the motor feed line and then to connect the motor feed line to sump. In a preferred embodiment, system pressure is connected to the plot to 'lock up' the valve in response to return line overpressurization.