Patent · US Expired

Power steering system

US5253729A · kind A · utility

27Cited by
5References
1Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 20, 1991
Grant dateOct 19, 1993
Priority date
Expiry dateNov 20, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/86654
  • WIPO fieldTransport
  • WIPO sectorMechanical engineering

Abstract

A steering system rotary valve having relatively rotatable spool and sleeve members and including first and second valve groups for controlling the amount of fluid feed to a power cylinder responsive to spool/sleeve rotation and including third and fourth valve groups for controlling feed pressure of fluid discharged from a pump, is provided with blocks arranged between the first and second valve groups and between the third and fourth valve groups to interrupt communication between these groups and also is provided with a variable throttle valve on the downstream side of the third and fourth valve groups so that pressure acting on all the valve groups is substantially equalized to provide uniform pressure on the entire circumference of the spool and the sleeve thereby preventing these members from becoming pressure deformed during the course of rotary valve operation.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.