Fluessigkeits-Hilfskraftlenkung fuer Kraftfahrzeuge

951,036. Vehicles' power assisted steering. GENERAL MOTORS CORPORATION. Sept. 6, 1962 [Sept. 13, 1961], No. 34216/62. Heading B7H. A steering linkage booster comprises a servocylinder 44 and a valve housing 42 spaced from one another coaxially and rigidly interconnected by an adaptor member 40 having at least one projecting connecting member 30a, 32a (Fig. 2) for connection to a steering link 30, 32. The open centre valve spool 48 (Fig. 2) is rigidly connected to sleeve 66 which encloses ball end 58 of pitman arm 56, movement of which operates the valve. Feel is provided on relative movement of valve 48 and housing 42 by both spring 92 and the pressure of the fluid displaced from chamber 80 either by shoulder 96 of the valve spool when the spool moves to the right or by the face of combined spring seat and seal 90 which is moved to the left by washer 76 when the spool moves to the left. The pressure in the working chamber 126 or 122 of the servo-cylinder is communicated to chamber 80 through annulus 106 and passage 129.