HYDRAULIC STEERING UNIT

Hydraulic steering mechanism is extended through an aperture in an end wall in a housing that has a pressure chamber, the steering mechanism including a slide rotatable with the steering column. An axial bearing is mounted by the end wall for rotatably mounting the steering mechanism while the aperture axially opposite end portion mounts a sealing ring between the housing and the steering mechanism. Axially between the sealing ring and the bearing there is a pressure reduction ring providing an annular gap with the slide for throttling the flow of fluid from the pressure chamber to a fluid collecting chamber that at least in part is defined by the pressure reduction and sealing rings. Fluid can flow from the collecting chamber through a housing outlet. The pressure reduction ring has an enlarged diameter flange for sealingly engaging the end wall and being clamped between the wall and the axial bearing. Increased pressure in the pressure chamber results in the flow of fluid through the gap increasing to automatically increase the pressure drop created by the throttle effect of the pressure reduction ring and thereby keeping the load on the sealing ring small.