DE3321085

A power assisted steering gear has a toothed part 1 such as a pinion coupled through a torque responsive rod 12 to an input shaft 4 so that rotation of the shaft 4 rotates the pinion 1 to drive an output member having a servo motor associated therewith. Fluid flow to the servo motor for power assistance is controlled by the valve 6 by displacement of component parts of the valve during relative rotation between the input shaft 4 and the pinion 1 as permitted by the rod 12. The valve 6 and pinion 1 form a unified assembly 7 carried on the shaft 4 and which is inserted into and removed from the housing 3 (by way of a side port 15) in unit manner. The assembly 7 is retained in the housing 3 solely by means, such as a spring clip 25, which is readily accessible from the exterior of the housing. The unified assembly 7 is rotatably borne in the housing by bearings 16 and 17 which may form part of the assembly for removal therewith or be retained within the housing following removal of the unified assembly. The bearing 16 journals a shaft part 19 formed by an extension of the rod 12 through the pinion 1.