Zf Friedrichshafen Ag

Zf Lenksysteme Gmbh

Rainer Sch&auml;nzel

Werner Breitweg

J&uuml;rgen Bieber

A rotary slide valve for power-assisted steering systems of motor vehicles includes a rotary slide which is connected fixedly in terms of rotation to a valve input member. The control bush is connected fixedly in terms of rotation to a valve output member. The two valve elements are arranged so as to be movable coaxially one in the other and are rotatable relative to one another at most by the amount of the rotary travel of a backlash coupling. The rotary slide has outer and the control bush inner longitudinal control grooves which cooperate with one another in order to control a pressure medium to and from two working spaces of a servomotor. The rotary slide is connected to the valve output member via a torsion-bar spring. Production-related tolerances which may lead to undesirable effects in driving behavior are compensated by a connecting element.

Rotary shift valve for servo-assisted steering systems of motor vehicles

A rotary shift or slide valve (,) for power steering systems of motor vehicles contains a rotary slide (,) linked to a valve input element (,). A control bush (,) is guided in an axial bore (,) of the rotary slide (,) and rotatable by a limited angle. The control bush (,) forms a rotation-fixed link with a valve output element (,). Between the rotary slide (,) and the valve output element (,), there is a centering device, which contains two centering elements (,), which can be rotated against each other, and at least one anti-friction element (,) located between the two centering elements (,). One of the centering elements (,) forms a fixed link with the reaction piston (,) and a rotation-fixed but axially displaceable link with the valve output element (,) via a metal bellows (,). The other centering element (,) forms a rotation-fixed and non-displaceable link with the rotary slide (,). The reaction piston (,) in the area of the centering device is arranged radially around the rotary slide (,) and projects in axial direction into the area of the rotary slide (,). As a result of this intra-positioning of components, the axial length of the rotary shift valve is reduced.

Growing community of inventors

Essingen, Germany

Rainer Schänzel

Growing community of inventors

Essingen, Germany

Rainer Sch&auml;nzel

Rainer Schänzel