Abstract: A steering system includes a user-manipulable steering control, a steering actuator, a pump, and a first valve assembly configured to control a flow of fluid from the pump to the steering actuator in response to manipulation of the steering control. The steering system also includes a rotary device coupled to the steering control. The rotary device is configured to direct fluid in response to manipulation of the steering control. The steering system further includes a second valve assembly movable between a first position in which the rotary device is not in fluid communication with the steering actuator and a second position in which the second valve assembly fluidly communicates the rotary device with the steering actuator.

Abstract: A vehicle is provided with a chassis having a footprint, a load carrying structure, and a support assembly coupling the chassis and the structure. The support assembly is adapted to move the structure relative to the chassis between a stowed position and a deployed position outboard of the footprint of the chassis. A plurality of wheels is configured to roll on the support surface and a plurality of axles coupling the wheels to the chassis are provided. Each axle includes at least one spindle supporting an individual wheel for rotation on a spindle axis. A steering system is adapted to position the wheels between driving and rotation arrangements with respect to the chassis such that in the rotating arrangement each of the plurality of wheels rotate relative to the chassis whereby the chassis, the platform and the support assembly may rotate in unison about the steer axis.

Abstract: The present invention relates to a steering apparatus for turning front wheels of a tractor. More particularly, the present invention provides a steering apparatus for tractors which includes a steering cylinder provided with left and right cylinder rods which are extended and retracted to the left and the right by steering force transmitted by hydraulic pressure when the driver manipulates the steering wheel, wherein swing links are respectively hinged to ends of the left and right cylinder rods, thus forming a first four-bar link structure, and second four-bar link structures are respectively formed on left and right ends of the first four-bar link structure so that the front wheels can be turned, whereby an angle range within which the front wheels can be turned can be increased.

Abstract: An integral power steering apparatus includes a hydraulic actuator having a piston separating pressure chambers for steering assistance and a limiter valve to be opened by movement of the piston to fluidly connect the pressure chambers. The limiter valve includes an adjuster for adjusting a press-fit position of a spring pin press fit in a plunger. The adjuster includes a movable adjusting member formed with an abutting surface to abut against the plunger to limit rearward plunger movement when the movable adjusting member is at a first adjuster position, and a regulating member to hold the movable adjusting member at the first adjuster position at the time of adjustment, and to enable the movable adjusting member to move to a second adjuster position after adjustment.

Abstract: A power steering system for a ground vehicle includes an accumulator that supplies high-pressure fluid through a control valve to a fluid motor that drives the steerable wheels of the vehicle. A normally open control valve between the accumulator and the fluid motor closes prior to the steerable wheels reaching an axle stop to relieve power assist.

Abstract: A steering system arranged in a vehicle having a steering wheel, a steering system control unit and a steering assistance unit with an electric motor. The steering system is designed to assist, by the motor of the steering assistance unit, a predefined steering movement of a driver at the steering wheel for steering steerable wheels of the vehicle and to steer the steerable wheels in accordance with the predefined steering movement. In this context, the steering wheel is mechanically coupled to the steering assistance unit. The steering system is also designed to block a predefined steering movement at the steering wheel, and therefore to block steering of the steerable wheels by the steering assistance unit, in a predefined state of rest of the vehicle.

Abstract: A driving force distribution control apparatus and driving force distribution control method for a four-wheel drive vehicle which can quickly increase torque distribution to sub-drive wheels after a transmission has been shifted down. According to the apparatus and method, when it is determined that the transmission has been shifted down, an ECU controls a coupling capable of changing the torque distribution to the front wheels and rear wheels such that the torque distribution to the front wheels and rear wheels approaches a uniform state.

Abstract: An integral power steering apparatus includes a stroke limiter. A piston defines two hydraulic chambers in a housing. A communicating passage, a first valve disposed between the first hydraulic chamber and the communicating passage, and a second valve disposed between the second hydraulic chamber and the communicating passage, are provided to serve for a stroke limiter, in addition to a hydraulic circuit for supplying hydraulic fluid to the two hydraulic chambers. The two valves each include a valve body having a bore and serving as a valve seat, a plunger slidably fitted within the bore of the valve body and serving as a valving element, and a spring disposed on the bottom of the bore of the valve body and biasing the plunger to be in contact with the valve body.

Abstract: A power steering system for a vehicle, comprises a steering shaft connected to a steering mechanism. A hydraulic power cylinder is provided for assisting a steering effort of the steering mechanism. A reversible pump is provided having first and second discharge ports which are respectively connected through first and second hydraulic lines with two hydraulic pressure chambers of the hydraulic power cylinder so that the two hydraulic pressure chambers are respectively provided with hydraulic pressures. A driving device is provided for driving the reversible pump to rightly and reversely rotate. A differential pressure regulating valve is disposed in the hydraulic circuit to maintain pressure at least in the first and second hydraulic lines at a level of atmospheric pressure or higher in an inoperative condition of the reversible pump.

Abstract: A power steering system is provided which comprises a bypass conduit connecting between first and second communication conduits and having bypass conduit ports. A pair of valves disposed in the bypass conduit for selectively opening and closing the bypass conduit ports in response to the pressure fluid from the pressure source. The valves are adapted to provide communication between the first and second communication conduits when the hydraulic pressure source is inoperative.

Abstract: A power steering system is provided which comprises a bypass conduit connecting between first and second communication conduits and having bypass conduit ports. A pair of valves disposed in the bypass conduit for selectively opening and closing the bypass conduit ports in response to the pressure fluid from the pressure source. The valves are adapted to provide communication between the first and second communication conduits when the hydraulic pressure source is inoperative.

Abstract: A steering axle with hydrostatic two-circuit steering system for agricultural, forestry and construction vehicles. The steering axle includes a first double-acting pressure medium cylinder (1) which in the area of its center is connected with an axle bridge housing (2) and at its two ends with joint housings (4, 5) via tie bars (3) and an additional second double-acting pressure medium cylinder (6) which is mounted on one side of the axle. The second cylinder acts simultaneously together with the first pressure medium cylinder (1). In this manner a two-circuit steering system is obtained. At the same time said second double-acting pressure medium cylinder (6) is connected at one end via a ball joint (7) with a joint housing (5) and at the other end is fastened on the axle bridge housing (2).

Abstract: A self-propelled boom vehicle has an extendible axle and an extendible steering mechanism which has an automatic steering synchronization system. The extendible axle has a hollow central support sleeve and telescopic arm sections. A single hydraulic extension axle is positioned inside the hollow central support sleeve and connects to and drives the telescopic arm sections between their retracted and extended positions. The steering synchronization system includes a pair of steering cylinders in a closed hydraulic circuit working in a master-slave arrangement and which operate inversely with respect to each other. A mechanical check valve is carried by each piston which allows excess hydraulic fluid to flow through the check valve to allow the piston to travel to the end of its stroke to resynchronize the steering.

Abstract: A self-aligning steering system for a vehicle having a steering wheel and a plurality of front wheels. The invention has a hydraulic fluid circulation means responsive to the steering wheel and a left and a right hydraulic cylinder for maneuvering the front wheels in response to the hydraulic fluid circulation system. The hydraulic cylinders have an internal fluid release system such that the volume of hydraulic fluid in the left and the right hydraulic cylinders is equalized through the hydraulic fluid circulation means. Equal hydraulic fluid volume ensures that the front wheels are in alignment.

Abstract: A four-wheel steering system for a vehicle including a front wheel Steering part having a front direction control valve having ports which close and open in accordance with a rotating direction of a steering wheel, and a front actuator for pushing or pulling a tie rod connected to a front wheel, an electronic control unit for controlling a steering of the rear wheels in response to signals transmitted from a vehicle speed sensor, a steering angle sensor and a steering amount feedback sensor, and a rear wheel steering part having first and second solenoid valves independently controlled by said electronic control, first and second rear direction control valves independently controlled by said electronic control unit and first and second rear wheel actuators for pulling or pushing said rear wheels selectively or simultaneously.

Abstract: The starter motor power cables for the starter motor, having a relatively large cross sectional area and therefore involving a very little voltage drop, are used as a part of the motor drive power cables for the electric power steering system, and the length of the motor drive power cables can be thereby reduced with the net result that the overall voltage drop can be reduced, and a sufficient power output can be produced from the electric power steering system. Also, the reduction in the length of the motor drive power cables reduces the possibility of producing electromagnetic interferences.