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, 1978
Filed:
Nov. 24, 1976
Johannes Vagn Baatrup, Sonderborg, DK;
Thorkild Christensen, Nordborg, DK;
Danfoss A/S, Nordborg, DK;
Abstract
The invention relates to a hydraulic control unit for a servomotor of the type used for vehicle steering systems. The unit has a control circuit with a power operated pump and a hand operated metering motor and an operating circuit with a power operated pump. The two circuits intersect upstream from the servomotor. A pressure comparison, throttling and proportioning valve is disposed between the outlets of the two pumps of the control and operating circuits. The proportioning valve is controlled by a differential pressure applied by the pumps and a spring which supplements the operating pump pressure. In the normal operating mode the proportioning valve allows a minor fractional flow of the pressurized fluid generated by the control pump to flow through the valve to the operating circuit. Under varying conditions when either of the pumps become wholly or partially inoperative the proportioning valve provides for an increased flow from the unaffected circuit to the disabled circuit to maintain a degree of operation until such time that the breakdown has been cured.