Rack and pinion steering gear

US4865149A · kind A · utility

Inventors

• Wolfgang Rohrbach · Mainz, DE
• Georg Grafenstein · Niedernhausen, DE
• Wilhelm Beer · Gerolzhofen, DE
• Burghardt Kiy · Gerolzhofen, DE
• Eugen Monetha · Gerolzhofen, DE

Key dates

• Filing date: Mar 2, 1987
• Grant date: Sep 12, 1989
• Expiry date: Mar 2, 2007

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B62D3/12
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A rack and pinion steering system, especially for motor vehicles, has a toothed rack that can be axially displaced in a steering gear housing, a pinion driven by the steering wheel and actuating the toothed rack, and a spring-loaded pressure part supported in the steering gear housing which serves to generate a certain pressure between the toothed rack and the pinion. Measures to raise the coefficient of friction which come into frictional contact with each other--in each case only in the region corresponding to straight-ahead driving--are provided on one or more surfaces of the steering system. As a result of such measures to increase the coefficient of friction at certain friction points in the steering system relating to straight-ahead motion of the vehicle, it is a simple matter to achieve an increase in steering torque in the center region of the steering system without the need for geometrical changes to the steering system or an increase in the pressure between the toothed rack and the pinion. The steering torque increase resulting from increased friction in the center region of the steering system compensates for the wear effects which are known to occur there after the veh…