Abstract: A rack-and-pinion steering system has a rack which is toothed on two sides and cooperates with two pinions. At least one of the pinions can be axially translated in dependence on forces acting between the rack and that pinion. This axial translation controls a clutch arrangement so that a servomotor continuously rotating in one direction can in each case be nonpositively coupled to one of the pinions or uncoupled from both pinions.

Abstract: A rack-and-pinion steering or control system with a servomotor, especially an electric motor, which can be coupled to the rack by way of a mechanical transmission and runs continuously in one direction is provided. The rack is designed over a certain area as a screw which interacts with a recirculating ball sleeve which can be driven in two directions of rotation by the motor. To control the direction of rotation, use is made of normally disengaged clutches which can be controlled as a function of a small displacement of the recirculating ball sleeve.

Abstract: The invention relates to a servo-assisted rack-and-pinion steering system having a helical-toothed rack and an axially movable pinion which interacts therewith and the axial movement of which controls the servomotor. The pinion is mounted on an input shaft in such a manner as to be incapable of rotation with respect to the shaft but axially movable thereon, in order to suppress the transmission of axial forces between the input shaft and the pinion.

Abstract: A servo-assisted rack-and-pinion steering system in which the rack is drive-coupled to a pinion which is mounted to move between two end positions in the longitudinal direction of the rack so that its movements control the servo motor. The end positions of the pinion are defined by two friction wheels which are driven continuously in opposite directions by the servo motor, in each case allowing an auxiliary force to be transmitted to the pinion.

Abstract: A servo-assisted rack-and-pinion steering system is provided in which the rack cooperates with a rotatable pinion. The pinion is supported in an eccentrically located opening in a circular disk rotatably mounted by rolling elements on its periphery. Pivoting movement of the pinion controls an hydraulic oil actuated servo motor. The rolling contact bearing of the disk lies in the path of flow of the hydraulic oil for the servo motor. The pinion is supported in a bearing in the opening in the disk and another bearing at an opposite side of the rack and separate from the disk.

Abstract: A servo-assisted rack-and-pinion steering system includes a rack which cooperates with a pinion which is capable of limited movement transversely or, in particular, parallel to the longitudinal axis of the rack. The movements actuate the servomotor or its control elements.

Abstract: A servo valve arrangement with a high-pressure, low-pressure and motor connection and with a pressure control valve arranged between the high-pressure connection and motor connection and a return control valve arranged between the motor connection and low-pressure connection is provided. The pressure control valve normally is closed and the return control valve normally is open. The pressure control valve can be opened by a common actuating member whilst closing the return control valve. The valve arrangement is suitable, in particular, for hydraulic power steering systems of motor vehicles with a so-called closed center.

Abstract: A servo control for power-assisted steering for motor vehicles having two coaxial shaft parts that are positively coupled to each other, but with play. The shaft parts are coupled such that limited relative rotations between these shaft parts are possible against the resistance of a pretensioned spring arranged in between. These relative rotations cause a pivoting stroke of a lever arranged between the shaft parts, this lever thereby actuating the control spool of a servo valve.

Abstract: A steering wheel end shaft part and a gear end shaft part are connected together elastically by means of a mechanism located between the shaft parts, the relative rotation between the shaft parts being converted into a large-stroke pivoting movement of a setting lever which actuates a control valve unit of the power steering system.

Abstract: A power steering system for motor vehicles, wherein a steering nut, connected to a steering worm in such a manner that the steering worm is driven thereby, is rotatably and axially non-displacably mounted in a working piston and is also provided with a control arm passing through both a radial recess in a working piston and a radial opening in a cylinder housing that receives the working piston. An end of the control arm which is radially outermost with respect to an axis of the piston actuates a spool valve for adjusting the working pressure. Two corresponding followers are provided for defining the end stroke positions of the working piston. The followers are mutually engagable to lower or shut off a working pressure in the system. One of the followers is disposed opposite the working piston relative to the piston axis and the other is located opposite the cylinder housing relative to the cylinder axis with a zero motion.

Abstract: A servo-steering mechanism for vehicles with a feedback of a load-dependent reaction moment onto the steering hand wheel by means of at least one reaction pressure cylinder connected with a working pressure chamber, in which a reaction pressure piston operating onto the steering hand wheel is adapted to be actuated in one direction of its piston axis by the working pressure and in the other direction of its piston axis is adapted to be supported at a support spring and is also adapted to come into abutment at a stop fixed relative to the reaction pressure cylinder, when the working pressure has been brought to a value corresponding to the prestress of the support spring; between its starting position with an unstressed support spring and its shut-off or turn-off position at the associated stop the reaction pressure piston thereby comes into additional abutment at least at one reducing spring counteracting the working pressure, whereby the reducing spring is adapted to be supported either directly or by way of

Abstract: A by-pass valve for servo-steering systems to turn off the working pressure in a cylinder chamber of a pressure medium cylinder, whose valve housing includes a valve connection adapted to be connected with the cylinder chamber, a valve connection adapted to be essentially pressure-relieved, and a valve seat for a check valve operatively connected between the two valve connections; the valve housing is thereby adjustable relative to the axis of a steering shaft for purposes of changing the position of its valve seat while the closure member of the check valve is thereby retained by springy means in its normal position closing-off the valve connections with respect to one another and is actuatable into its by-pass position connecting the valve connections with each other by way of a stem movable in unison with the closure member by way of a cam surface fixed for movement in unison with the steering shaft; the valve housing is thereby exclusively rotatable in relation to its valve housing axis but is immovably s