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:
May. 28, 1991
Filed:
Nov. 09, 1989
Applicant:
Inventor:
Douglas M Gage, Dubuque, IA (US);
Assignee:
Deere & Company, Moline, IL (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B66C / ;
U.S. Cl.
CPC ...
414729 ; 60493 ; 91420 ; 137106 ;
Abstract
A check valve assembly having first and second check valves and an unseating spool is positioned between a control valve and a rotary motor. The unseating spool is elongated so that it continually contacts the valve elements of the check valves. The check valve hydraulically coupled to the higher pressure supply/return line drives the unseating spool against the valve element of the other check valve opening it and connecting the associated supply/return line having lower hydraulic pressure to reservoir through the direction control valve.