Abstract: A potentiometer for the redundant measurement of the angle of rotation of a shaft compared with a fixed member has two resistance paths located concentrically with each other on a fixed disk. Two collector paths having the shape of circular rings are located concentrically with each other on a disk situated parallel to the fixed disk and rotating together with the shaft. Two slide contacts connected with the collector paths are in contact with the two resistance paths. Two redundant measured values are tapped at two terminal contacts fastened to the fixed disk that are in contact with the collector paths through two slide contacts.

Abstract: In an electrically-assisted rack and pinion auxilliary steering mechanism, an electric motor is controlled in accordance with a signal from a torque-measuring device. To prevent faulty control messages, a safety switching device is provided that contains two switches capable of being activated by a lever. A ball nut that is connected with a threaded spindle by a ball diversion channel is connected with the steering rack of the rack and pinion steering gear. The threaded spindle is connected via a spring bellows, with an output part of a coupling that can be coupled with or uncoupled from the electric motor. The threaded spindle is connected, axially movable and rotatable, opposite the fixed housing by two elastic intermediate rings and two axial bearings. If the axial movement does not coincide with the torque at the steering wheel in case of a malfunction, the coupling is disengaged by one of the two switches.

Abstract: A torque sensor for measuring the torque being transmitted by a torque bar comprises a pair of coaxial input elements carried on a torque bar and secured thereto, and being connected by a lost motion coupling. Each such input element has flexible spokes fixed to respective sides of an output collar. Steering torque stress applied to the torque bar in either direction effects rotation of a respective input element depending on direction of rotation. Thus, such directional rotation causes flexing of the flexible spokes between an input element and the output collar. Linear longitudinal movement of the output collar is thus caused in a direction depending on the direction of rotation of a respective input element. The direction and degree of movement of the output collar serves to vary a magnetic field to which an electrical measuring circuit is responsive for torque measurement. Two torque sensors can be connected in series with respect to the same torque bar to achieve various measurement effects.

Abstract: In an electrically-assisted auxiliary power steering mechanism an electric motor (11) is controlled by a control circuit (9) according to an output signal X1) from a torque-measuring device (8). To prevent instances of faulty control a redundant safety circuit (14) with a safety device (15) and a switching device (16) controls a disconnecting element (13, 27) located between the electric motor (11) and the steering gear (1) that switches the electric motor (11) on and off. A second torque-measuring device (17) for measuring the torque of the electric motor (11) is disposed between the electric motor (11) and the steering gear (1). The switching device (16) of the safety circuit (14) activates the disconnecting element (13, 27) when the torques measured by the two torque-measuring devices (8, 17) have different directions.

Abstract: A Servosteering system especially for motor vehicles utilizes a piston type of control valve having reaction chambers for simulating steering resistance in the course of a turn. Communication for pressure flow to the reaction chambers is via fixed throttle in series with a speed responsive variable throttle which at low speeds reduces the simulated steering resistance to low or nonexistent, as in parking, but varying to higher steering resistance at higher speeds. Additionally, a pressure reduction valve is series connected with the fixed throttles. Reaction chamber pressure is thus held to a maximum so that simulated steering resistance, is comfortable in a tight turn.

Abstract: In a servosteering arrangement, a control mechanism combines a pressure operated valve responsive to servomotor chamber pressure, and a solenoid and plunger responsive to speed of the vehicle by means of a proportional magnet solenoid for controlling reaction chamber pressure and thus the manual force required to be exerted by a driver for steering a vehicle. Thus, a variable throttle pressure responsive valve combined with a speed responsive solenoid responsive inversely to speed, controls the manual steering force necessary to effect steering at various speeds, particularly in tright curves at low speeds with high servomotor pressures. An important safety feature in the event of failure of solenoid current is the maintenance of openness of the pressure operated valve with consequent high resistance to steering.

Abstract: A steering control piston valve has reaction chambers and respective fixed restrictor orifices having an interconnector conduit. The reaction chambers have respective inlet and outlet flow control valving which serve to permit flow from either reaction chamber to bypass the respective restrictor orifice during a steering maneuver if the steered wheels receive a road jolt. The arrangement provides for very rapid flow from the reaction chamber being decreased in volume due to the jolt force on the valve piston causing it to move oppositely to the steering direction. The flow from such reaction chamber passes to the interconnecting conduit for storage. An additional storage tank can be connected to the interconnecting conduit to increase the storage capacity if necessary. The bypassing is likewise advantageous in the event a vehicle swerves and rapid steering correction is necessary.

Abstract: A device for setting the air gap between an armature and an energizable electromagnet, which utilizes a pin that can be force fitted in the armature by a tool forcing it against spring bias for a distance limited to the thickness of a collar on the pin. In so doing, the spring is transformed from an unstressed to a stressed condition so that upon return movement of the spring the collar, pin, and armature are actuated a distance equal to the thickness of the collar thereby setting the air gap.

Abstract: A compact power steering device is provided wherein the power steering valving is actuated by axial movement of a pinion having helical teeth engaging a rack in a steering housing. The valving utilizes head and seat valves with valve heads and coacting valve seats which are actuated on axes parallel to the pinion axis within the housing and requiring no more than the overall distance occupied by axial movement of the pinion as effected by rotation of a steering wheel during steering. Opposed springs effect a centered position for the pinion in neutral position of the valving for straight ahead steering. Thus, a centering spring is dominant and limited in movement to fix the valving as biased by other springs to a precise neutral position.

Abstract: A booster steering valve control of the kind that comprises a pair of valve pistons reciprocal in a rotative valve body are driven by a fork shaped member at the end of a steering spindle. The fork shaped member comprises a pair of spaced actuator pins which engage in openings of the respective valve pistons. Thus, the valve body and the fork shaped member have a common axis about which the actuator pins rotate. A particular construction of the invention resides in the displacement of the actuator pins such that their axes are not in a common plane with the steering spindle axis but offset so that the surfaces of engagement between the actuator pins with the respective valve pistons and the spindle axis are coplanar. Engagement is maintained by spring bias acting on the valve pistons.

Abstract: A booster steering valve control device of the kind having a rotative valve body within a steering housing with a pair of piston valves operative upon rotation of a steering spindle is provided with reaction chambers at corresponding ends of the piston valves. The reaction chambers are isolated from an inlet chamber within the steering housing by means of closure caps. The closure caps are secured in place by a resilient clamp held by a bolt carried in a bore of the valve body in which the valve pistons are reciprocal.

Abstract: A servosteering control valve is provided with fluid reaction chambers which are pressued responsive to the speed of a vehicle for effecting a simulated steering resistance wherein at low speed, as in parking, there is no steering resistance and resistance increases with speed via feedback from the chambers of a double acting servomotor. The novel feature of the arrangement herein utilizes a coaction between the inlet flow control passage and return flow control passage of a steering control spool or piston valve, one such valve for each chamber. This is in conjunction with throttle passages disposed between the manually shiftable piston valves and a valve housing. Such passages are created by portions of the shiftable valves having elements slightly smaller in diameter than the diameter of the housing bore or bores in which the valves are shiftable. A single bore is used where the valves are coaxially integral and respective bores are used where the valves are separably movable.

Abstract: A hydraulic power steering system having an unbalanced piston servomotor and a pair of identical control valve pistons controlling flow of pressurized fluid to the servomotor for balanced directional displacement of the servomotor piston and to separately control depressurization of feedback chambers acting on the control valve pistons. Pressurized fluid is supplied directly to the feedback chambers from the servo-steering pump through flow restrictors, one of which is externally adjusted to select the degree of road sensing feedback generated to oppose manual actuation of the control valve pistons.

Abstract: Fluid reaction chambers are continuously pressurized by fluid supplied through fixed flow restrictors to develop equal resistances to displacement of a steering control valve in opposite directions. The reactive resistances developed by two reaction chambers are separately regulated in directional response to displacement of the control valve by discharge of fluid from at least one of the reaction chambers at a flow rate that varies as a function of vehicle speed.

Abstract: A valve is intermittently actuated under control of speed dependent signals to influence operation of an auxiliary power steering system. Digital speed signals from a sensor are processed in a microprocessor storing steering function data for transmission by an interfacing stage to an electromagnetic actuator for the valve.

Abstract: A pair of fluid reaction chambers at opposite ends of a valve piston of a steering control valve are connected in series with a vehicle speed dependent control mechanism by fixed flow restrictors between the servo pump and reservoir of a servo power steering system. Check valves unidirectionally limit pressurization of the reaction chambers through which feedback forces are generated in response to displacement of the control valve.

Abstract: An auxiliary fluid power steering device having a servomotor (8) and a control valve (13) in a common steering gear housing (1). In order to relieve the control valve of axial pressure forces, the valve body (14) of the control valve has four surfaces (24, 25, 26, 27) of equal area respectively exposed exclusively to fluid in the inlet port (22), in the outlet port (23), in one of the servomotor pressure chambers (9) adjacent the control valve and in the other pressure chamber (10) of the servomotor.

Abstract: A simplified construction of a comparator is provided in an automatic steering system utilizing dual chambers separated by a membrane, e.g., a diaphragm or bellows. Each side of the membrane operates a respective valve which valves are normally open but can control flow to a hydraulic cylinder for steering or centering the wheel of an agricultural vehicle. Fluid flows through the chambers which connect to exhaust through variable throttle valves. Sensors, i.e., feelers, follow rows of plants and when the feelers are deflected they operate respective throttle valves which cause a buildup of pressure in a respective chamber. Such differential pressure between the chambers flexes the membrane in a direction to operate the valves within the chambers. Operation of such valves effects directional pressurizing of a hydraulic motor to steer the vehicle wheel.

Abstract: One or more pressure regulators limit the operating pressure of fluid supplied to a fluid pressure operated device from a common pump and control the level of the operating pressure through pilot valves connected to the regulators. Each fluid operated device is connected by its regulator to a common fluid reservoir when flow is blocked in the pump pressure and suction lines to limit the operating pressure while minimizing pump drive energy loss.

Abstract: A solenoid operated valve is provided particularly constructed to decrease friction in the course of operation and thus of the hysteresis or actuating lag effect. The general construction utilizes a solenoid acting to maintain closure of a valve by pulling on an armature to which is integrally secured a valve operating element having a valve head at one end and which passes through the core on which the solenoid is mounted. The armature has a piston formation extending into a pressure chamber of the housing. Pressure in the outlet of the valve communicates with the pressure chamber to maintain a net closing effect on the valve. Accordingly, pressures at the valve are prevented from acting against the energized solenoid.