Abstract: Passage bridging cavities formed in a steering gear housing communicate with annular grooves in a cylindrical valve element through recesses in the cavities at limited, and angularly spaced valve edge locations to control distribution of pressurized fluid in a hydrostatic power steering system in response to axial and rotational movement of the valve element.

Abstract: Axially spaced and aligned longitudinal distributor grooves are formed in the radially outer surface of a thin-walled tubular valve element in angularly spaced relation to internal grooving of the valve element for conducting pressurized fluid and establishing a torsional coupling in a hydrostatic controller associated with a power steering system. Obliquely orientated bores in the valve housing establish fluid communication between the longitudinal grooves adjacent opposite axial ends of the housing and axial passages in the housing.

Abstract: Axially spaced distributor grooves externally formed on a rotatable controller valve element conduct pressurized fluid to a servomotor in response to axial displacement of the valve element within a housing enclosing pressurized spaces to which opposite axial ends of the valve element are exposed. Flow of the pressurized fluid through the grooves is controlled by slide valve surfaces on the valve element axially between the pressurized spaces and the grooves.

Abstract: In a steering control valve device of the kind utilizing a metering pump and a torsional stress means for returning the flow control valve sleeve to a neutral position, there is provided a coupling sleeve between the manually operable steering spindle and the valve sleeve. Such coupling sleeve is for the purpose of providing an intermediate actuating member between the steering spindle and the valve sleeve to overcome errors in alignment and other disadvantages which can occur in conventional constructions where the steering spindle directly actuates the valve sleeve wherein rotation of the steering spindle effects axial shift of the valve sleeve for flow control purposes. The invention is particularly advantageous where the means of translating rotary motion of the steering spindle to axial movement of the valve sleeve is effected by threaded coaction.

Abstract: An auxiliary steering flow control device having known features of a rotatable steering spindle which initially effects axial shift of a valve sleeve through a torsional stressing device acting on a pair of compressibly arched leaf springs longitudinally disposed on the axis of the steering spindle and carried in a holder within the steering spindle. The leaf springs have contiguous contacting arched surfaces on the steering spindle axis and the arched configuration effects a back to back pretensing that augments the potential energy that can be stored in the springs, particularly in arched surface contiguity with each other.

Abstract: A torsion rod is provided with articulated connections at opposite ends to transmit torque between a steering spindle and the universal shaft coupling of a pump rotor in a steering control valve. The end of the torsion rod coupled to the universal shaft is received in a bore that terminates close to the driven end of the universal shaft engaged with the pump rotor, the articulated connection to the torsion rod being located at said terminal end of the bore.

Abstract: The axial thrusts applied to two rotatable slide valve elements of a steering control valve assembly, are transmitted independently of each other through radially overlapping, anti-friction bearings to a common axial thrust absorbing surface. A thrust transmitting spacer positioned radially inwardly of one of the anti-friction bearings, extends axially between the other of the anti-friction bearings and the thrust absorbing surface.

Abstract: An annular gap between a valve shaft and the bore in a valve body of a steering control valve is dimensioned to accommodate relative eccentricity of parts and is sealed by a sealing gland having a rigid annular element rotatable with the valve shaft. The annular element is formed with recesses seating resilient sealing elements respectively engaging the valve shaft and an axial abutment surface of the valve body. The sealing elements are prestressed in radial directions and axial directions, respectively.

Abstract: Relatively dispaceable valve elements of a pressure controller for a vehicle steering system provided with radial bore type valve passages having two different flow area dimensions to regulate the pressure of fluid supplied to a servomotor in response to displacement of the valve elements to an operating position from a neutral position in which the valve passages establish a short circuit flow path between the pressure source and a low pressure outlet. Flow through the short circuit passages in the valve elements are blocked in sequence during displacement of the valve elements to the operating position by sequential closing of flow passages in one of the valve elements.

Abstract: Two fluid circuits respectively supply pressurized fluid from engine driven and vehicle pumps to separate servomotors in a vehicle steering system for steering operation during vehicle travel. Both fluid circuits are connected to the engine driven pump alone during vehicle standstill by a reversing valve which is shifted to a travel position by pressure output of the vehicle driven pump.

Abstract: A simplified overall hydraulic control system is provided for dual systems comprising a booster steering power cylinder and the power cylinder of an accessory of a work vehicle pressurized from a common engine driven hydraulic pump. The system utilizes conventionally constructed multiway valves for steering and accessory control and comprises flow dividing means effecting a constant minimum flow rate at all operational times for steering and variable flow rates for accessory power and additionally for steering dependent upon demand, essentially under vehicle operator control.A main steering flow to the steering control valve can connect with the minimum steering flow through a one way valve when steering is effected, less such flow as may be directed for accessory power by operation of the accessory control valve.