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:
Mar. 06, 1979
Filed:
Feb. 23, 1977
Leon E Hicks, Joliet, IL (US);
Wayne A Peterson, Joliet, IL (US);
Lawrence F Schexnayder, Joliet, IL (US);
Caterpillar Tractor Co., Peoria, IL (US);
Abstract
A method and plural embodiments of apparatus for delivering a pressure-compensated supply of fluid to a hydraulic steering circuit, wherein first and second pumps are respectively operated by a vehicle engine and by a ground wheel when the vehicle is in motion, output fluid from the two pumps being simultaneously directed to the steering circuit by a control valve with inlet relief valve means modulating output pressure of the sources in response to operation of the control valve. One embodiment contemplates dual inlet relief valves for separately modulating output from the two pumps while another embodiment contemplates one of the pumps having a variable output.