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:
Feb. 16, 1988
Filed:
Feb. 18, 1986
Frederick J Adams, Clevedon, GB;
TRW Cam Gears Limited, Hitchin, GB;
Abstract
A power assisted vehicle steering system has a rack and pinion steering gear 6 incorporating a servo motor 6a controlled by a valve 22. A fluid pressure supply line 3 to the valve 22 includes a throttle or regulating valve 5 which is adjustable by a stepping motor 30 that is speed responsive to increase incrementally the restriction by the valve 5 to fluid flow to the valve 22 as vehicle speed increases. A flow control valve 7 is responsive to fluid pressure in the line 3 upstream of the valve 5 and to fluid pressure in the line 3 downstream of the valve 5 so that a pressure differential across the valve 5 is sensed by spool 9 which is displaced to open the supply line 3 upstream of the valve 5 and a reservoir 1. This latter opening reduces the supply of pressure fluid available for actuating the servo motor 6a and the available power assistance as the vehicle speed increases.