Patent ID: 6178843
Filing Date: 2001-01-30
Classification: B62D,F16H,Y10T

Abstract:
A rack guide for a rack and pinion steering system, in which the rack guide is mounted in a casing of the steering system so as to slidably support a rack bar which is reciprocatingly driven by a pinion being rotatably supported in the casing, the rack guide comprisingsupporting base and an elongated slide bearing member which is mounted on the supporting base and which has a circular-arc cross-sectional profile, whereinthe slide bearing member comprises a backing metal layer and liner formed on the backing metal, the liner comprising a synthetic resin layer which forms an inner surface of the rack guide and which is brought into sliding contact with the rack bar;the inner surface of the rack guide, having said circular-arc cross-sectional profile, comprises circular-arc concave sliding-contact surface portions (25, 26) and circular-arc concave remaining surface portions (27, 28, 29), all of which are elongated longitudinally and which are circumferentially distinguished from one another;the sliding-contact surface portions (25, 26) are entirely in sliding contact with the rack bar and have a cross sectional circular-arc profile with a predetermined circumferential length having a first radius of curvature (R.sub.0), and which are continuous to the adjacent remaining surface portions; andthe remaining surface portions (27, 28, 29) are radially more recessed than the sliding-contact surface portions with first and second remaining surface portions (28, 29) being located adjacent the edges of said circular-arc profile and each having a second radius of curvature (R.sub.2) which is less than said first radius of curvature (R.sub.o), and with a third remaining surface portion (27) being located between said sliding-contact surface portions (25, 26) along a symmetric center line (L) of a said profile and having a third radius of curvature (R.sub.1) which is less than said first radius of curvature (R.sub.o).