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:
Aug. 10, 1993
Filed:
Sep. 16, 1992
Applicant:
Inventor:
Dieter Gawlick, Ludwigshafen, DE;
Assignee:
Deere & Company, Moline, IL (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B60T / ;
U.S. Cl.
CPC ...
60578 ; 60581 ; 60588 ;
Abstract
A two-stage brake valve includes a stepped valve bore and pressure piston defining a first stage with a large effective area and a second stage with a smaller effective area. The two stages become effective in succession so that, initially the first stage is used to fill a system and then, following a transitional phase, the second stage generates an operating pressure. A relief channel communicates the pressure chamber of the first stage with a reservoir. A relief valve closes the relief channel in response to an excess pressure generated by operation of the second stage.