Abstract: A pressure medium control means for hydraulic servo-steering devices with a pressure source and preferably a hydraulic pressure accumulator in which means there is provided a control valve having a four-way control and one or preferably two control pistons for selectively connecting the working spaces of a servo motor with a pressure source or return pipe to a reservoir, in which the servo motor is operably related to a power outlet member affecting the steerable wheels, with the power outlet member per se being connected with a power inlet member via a resilient, preferably pre-stressed coupling means, and in which the control piston or pistons is or are provided with reaction areas stressed by the pressures from the working spaces of the servo motor, or are in operative relation with respective reaction members and are actuable via actuating elements by virtue of relative movements between the power inlet member and the power outlet member.

Abstract: A method of sealing non-threaded boreholes with a preferably spherical sealing member comprising pressing the sealing member into the borehole in an unhardened raw material hardenable by nitridation, wedging the lip of the borehole and hardening the material by nitridation at a temperature at which at least some of the initial stress generated by the pressing is retained.

Abstract: A hydraulic pressure-regulating system for a dual-functioning servo motor having a control valve device that permits direct manual operation of the servo motor output function up to a predetermined force whereupon servo assistance arises when the fingers of the input member take up a set lost motion and directly contact and mechanically operate the control pistons. A prestressed spring holds the pistons in a neutral position to maintain a desired initial pressure in the system.

Abstract: A servo steering gear for motor vehicles has an alleviator controlled, constant pressure servo system including an input member operatively connected to a steering wheel of a vehicle and an output member operatively connected to the steered wheels of the vehicle. A servo motor is operatively connected to the output member, and is controlled by an arrangement including valve elements so disposed that an automatic restoration of the steered wheels can take place and that pressure-loaded reaction faces provided on the valve elements generate a reaction which a driver of the vehicle can feel, and which, at least within a defined range, depends on the reactive forces generated by the steered wheels.

Abstract: A steering worm shaft in operational connection with a steering wheel and communicating with an axially slidably arranged steering gear nut, which gear nut affects an additional gear member, for example, by means of a toothing, and simultaneously functions as a servo-piston or is at least fixedly connected to a servo-piston within a housing, which contains a cylinder space; the servo piston dividing a cylinder space into two operational spaces, which are separated from each other, and the steering gear nut at its outer cover is provided with an outwardly extending, axially directed lever in an area remote from the sealing area of the servo-piston; the axial width of the lever corresponding at least with the lift of the servo-piston and engaging an axial-parallel groove in the housing to allow the lever to perform a minute tilting movement relative to the housing when the steering gear nut, due to friction and rise of the worm gear nut during a rotation of the steering worm shaft, is also set into rotation, wh

Abstract: The springs associated with the control valves of a servo steering system are prestressed at least in that position of the valves where associated connections are blocked. Further, the springs are arranged supporting themselves in the valve by ends of the springs being arranged facing an activating member common to the valve and permitting the entire spring force to be received by the activating member alone. At least one component of each spring is supported by the valve housing, whereby the bias on the one component increases, based on the activating force limit during a reduction of the activating force, and reaches a maximum when power-flow between the activating member and the associated regulating spring is interrupted.

Abstract: A control valve for hydraulic servo-steering systems embodying connections for a pressure-source, a discharge and a servo-steering motor provided with a valve member, with the valve member being connected with one section of a divided steering shaft or spindle, in which one or a plurality of adjustable control pistons or reaction pistons are arranged preferably transverse and off-center to the axis of the valve member, and are activated by an activator device rotatable through a small angle relative to the valve member, and connected with the other section of the steering spindle, the activator means being positioned with one part of its length in or on the valve member, whereby the valve member is rotatably and axially immovably positioned in a generally affixed connection body, or in a sleeve connected therewith, in a manner so that the supply and release of a pressure medium into or out of the valve member, independent of the relative position of the connection body and valve member to each other, is guara

Abstract: A control cylinder assembly for servo-steering systems including a fluid pressure circuit and steering shaft and an output shaft, in which a servo piston is supported during axial travel by axially spaced sleeves connected to a housing cover and the sleeves form circumposed fluid areas, and the piston forms opposed variable-volume operational areas, all of the areas being operatively connected in a fluid pressure circuit.

Abstract: A fluid pressure control device for controlling a servo motor is disclosed, the control device being provided with at least one pressure control valve for controlling pressure in a working chamber of the servo motor and transmitting a thrust corresponding to the pressure in the working chamber back to a power input member; operation of the pressure control valve being derived from the power input member through a lost motion coupling means.

Abstract: A hydraulic pressure fluid control system for controlling the displacements of a double-acting servo motor wherein a servo assisting valve mechanism comprises in addition to the control pistons for controlling and maintaining the pressures in the working chambers of the servo motor and the coil springs which place a predetermined minimum force to act on the pistons, spring retainers and further coil springs concentric and codirectional with the first coil springs arranged such that upon a movement of the input member of the system, a predetermined threshold force must be met before the input member directly couples with and controls the movements of the control pistons, the biasing of the coil springs and the further coil springs establishing the threshold value.

Abstract: The instant invention concerns a pressure medium control device for controlling the working chambers of a servo-motor, whereby said servo-motor is provided with two control valves which are actuated via actuator means through relative movements between a power input member and a power output member which is connected with said power input member by means of elastic, resilient, especially pre-stressed coupling means, and whereby the servo-motor is in operative connection with the power output member and the control valves are provided with reaction areas for reflecting the developing pressures to the power input member, and/or are in operative connection with one or a plurality of corresponding reaction members, whereby the power transmission from the power input member to the control valves, which is necessary for activating the control valves, is effected via a lost motion coupling to which a further elastic resilient coupling means is parallel-switched, especially for two control valves which are arranged t

Abstract: A servo steering system for motor vehicles has a stepped servo piston arranged in a cylinder-forming space of a housing for dividing the cylinder space into a pair of separated working spaces of different volumes. The servo piston is engaged by a worm shaft connected to a steering wheel of the vehicle and arranged extending into the housing. The working space having the larger volume is connected to a pressure source by a valve member operatively connected with a lever associated with the servo piston for controlling fluid flow through the working space and magnifying movement of the worm shaft, with the smaller volume working space of the servo piston being connected directly to the pressure source. Reaction spaces of a stepped control piston of the valve member are substantially in the same ratio as the working spaces of the servo piston.