Auxiliary power steering system with relief valve control

US4261248A · kind A · utility

Assignee

• Zahnradfabrik Friedrichshafen AG · DE

Inventors

• Dieter Elser · Oberkochen, DE
• Gerhard Kuhn · Altötting, DE

Key dates

• Filing date: May 22, 1979
• Grant date: Apr 14, 1981
• Expiry date: May 22, 1999

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B62D5/061
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

The maximum operating pressure for the fluid servomotor of a fluid power operated steering system is varied as a function of steering displacement by varying the spring prestress bias on a relief valve controlling fluid discharge from the operating chamber of the fluid servomotor. The valve spring prestress is controlled by a spring engaged plunger that is displaced relative to the servomotor piston during steering displacement.