DREHSCHIEBERVENTIL FUER HYDRAULISCHE HILFSKRAFTLENKUNGEN

摘要

PCT No. PCT/EP87/00524 Sec. 371 Date Jan. 31, 1989 Sec. 102(e) Date Jan. 31, 1989 PCT Filed Sep. 16, 1987 PCT Pub. No. WO88/01959 PCT Pub. Date Mar. 24, 1988.An auxiliary power steering mechanism with a working piston installed in the steering gear has a rotary valve comprising a rotary member and a fixed valve sleeve. A piston valve is inserted in a bore provided in the rotary member. The piston valve is connected with an adjustment device, such as an electromagnet, via a tube supported by a torsion bar. The electromagnet adjusts the piston valve as a function of various influencing variables such as speed, and controls the condition of a plurality of hydraulic fluid flow return bores arranged in longitudinally spaced relation in the rotary member for noise-free control of the build-up of pressure in a surge chamber that is active at the moment. The bores have flat portions of different contours and circumferential lengths.