Abstract: The power transmission device includes an input shaft that rotates about its axis together with a vehicle wheel. A driving gear is arranged coaxially with the input shaft so as to rotate about the axis of the input shaft together with the input shaft. A driven gear meshes with the driving gear, and configured to transmit a rotational force to an output shaft connected to a regenerative energy converter. A wheel bearing for the vehicle wheel supports the input shaft such that the input shaft is rotatable about its axis relative to the driven gear.

Abstract: A steerable vehicle knuckle has an inboard portion defining upper and lower arms, with a kingpin between them, and has an outboard portion defining a spindle that cooperates with a fluid driven motor. The arms define a cavity where an axle end portion is pivotally received. Fluid supply ports, which supply fluid to energize the motor, are located on an upper surface of the knuckle's inboard portion. Fluid drain lines extend within the knuckle from the motor to the cavity and are utilized to drain fluid from the motor. The supply ports and drain lines are each connected to separate hoses formed in a small arc that follows closely the circular curvature of the kingpin. This arrangement of port, lines, and hoses is less expensive to produce, easier to package, more robust, allows for faster steering reaction, and is easier to assemble than conventional arrangements.

Abstract: There are provided plural suspension links, one end of each of which is coupled to a wheel and the other end of each of which is coupled to a vehicle body. The suspension links are disposed so as to extend substantially in a vehicle width direction. A drive motor is disposed so as to be offset from a center of a wheel on a side that is away from disposition location of the suspension links. The drive motor and the wheel are coupled by a drive-force transmitting mechanism so that a drive force can be transmitted. Accordingly, there can be provided the disposition structure of a drive device for a vehicle that can provide both the drive motors and the suspension links without any improper interference, ensuring proper controlling of the wheel positions.

Abstract: In order to reduce the amount of air trapped in hydraulic assisted steering systems (1), a communication (13, 14) is established between the area of the oil expanding volume (8, 10, 11), which is the top area in the mounted position, and an open system (2), for example a tank volume.

Abstract: A method of controlling a vehicle hydraulic drive system of the type including a plurality of fluid pressure actuated wheel motors (13,15) connected in a parallel circuit with a source (17) of pressure. A flow restrictor valve (65) is disposed in a downstream conduit (27) of each of the wheel motors (13,15). The method involves determining the theoretical fluid flow for each motor, the actual fluid flow through each motor, and generating an error signal (107) which is then used to bias the restrictor valve (65) toward a flow restriction position. The disclosed method can be used to achieve steering at greater than kinematic, by scrubbing the inside front wheel, or can be used to prevent wheel slip of propulsion wheels, or can be used to prevent scrubbing of a wheel during hydrostatic braking, or can even be used to achieve vehicle steering.

Abstract: An articulating work machine, such as a scraper, wheel loader, or truck, is disclosed. The articulating work machine includes a fluid-powered differential and a pair of fluid-powered steering cylinders. The fluid-powered differential and the steering cylinders cooperate so as to steer the articulated work machine during advancement thereof. Moreover, the articulating work machine includes a number of rotational position and speed sensors for detecting operating parameters associated with the work machine. Such parameters are monitored by a processor in order to control operation of the work machine.

Abstract: A method is provided for controlling steering in a hydrostatic drive system having a differential steer mechanism that uses flow from the hydrostatic drive system to drive the differential steer motor. The method utilizes independently controlled brakes on the respective right and left drive units to assist the differential steer mechanism in the event the pressurized fluid from the hydrostatic drive system is reduced during the operation of the machine.

Abstract: A hydraulic servo control, particularly a hydraulic power steering system for motor vehicles, has hydraulic pressure pump which is driven by an electric motor. The rotational speed of the electric motor is controlled as a function of the load, so that a high rotational speed occurs only when there is a corresponding demand.

Abstract: Straight travelling apparatus for construction vehicles capable of keeping the construction vehicle travelling straight even when a work implement of the construction vehicle is manipulated during travelling. The apparatus includes hydraulic circuitry for making the hydraulic oil of first and second pumps be supplied to left and right travelling motors respectively when only the left and right travelling motors are operated, and making the oils be confluent together and equally distributed and supplied to the left and right travelling motors when even one work implement is to be manipulated at the same time as operating the left and right travelling motors. The hydraulic circuitry includes left and right directional selecting valves and a confluent line extending between the directional selecting valves for selectively making the hydraulic oil confluent together.

Abstract: The flow control for fluid circuits having dual power outlets includes a housing having an interior compartment with the compartment having an interior surface, center portion and first and second ends. The compartment has a maximum cross-sectional area at its center portion uniformly decreasing in area towards the first and second ends. First and second outlet fluid ports are located in the housing adjacent the first and second ends. A pressure fluid inlet port is located in the housing at the center portion thereof. A flow control element is mounted for longitudinal movement in the interior compartment and has an outer surface symmetrical in shape to that of the compartment, but has a smaller diameter wherein a fluid flow space exists between the outer surface of the control element and the interior surface of the compartment.

Abstract: The present invention is directed to a planetary steering system for a skid steered vehicle. A prime mover directs rotational motion through right and left drive shafts having planetary carriers with planet gears. The planet gears of the right and left planetary carriers rotate around a right and left sun gears that are coupled to right and left hydraulic steering motors. The planet gears rotate in right and left ring gears that are coupled to the right and left drive wheels of the vehicle. By rotating the motors the speed of the drive wheels can be independently controlled.

Abstract: A high crop agricultural vehicle has a chassis supported at an elevated position on front and rear sets of wheels. The front wheels are turnable through an arc of greater than 90.degree. so that they can be turned to a lateral travel position which is perpendicular to the direction of normal forward travel. In that lateral travel position the vehicle can be driven sideways. This allows the vehicle to be easily manoeuvred as well as facilitating the mounting of agricultural implements into the space between the front and rear wheels. The rear wheels are preferably momented in a castor-type mounting assembly.

Abstract: A hydraulic circuit for running a crawler vehicle which comprises a running frame portion provided with motors for running the crawler vehicle and an upper swivel portion turnably disposed on the running frame portion via a swivel joint. Electro-magnetic proportional flow directional control valve (a directional control valves) (15) for controlling the running motors are disposed between the swivel joint (41) and the running motors (19). The number of the high pressure passages in the swivel joint (41) can be reduced, because of increase of pressure resistance, the size of the swivel joint can be small, and accordingly, the hydraulic circuit for running a crawler vehicle can be inexpensive, and possibility for leakage of pressure oil becomes low.

Abstract: Steering systems are normally incorporated into hydrostatic drive systems for use on track-type vehicles. The currently available steering systems do not take advantage of the potential energy created by slowing down the inside track during a steering maneuver. The subject regenerative steering system includes positioning a pair of reversing valves between a source of pressurized fluid and a pair of motor/pump units drivingly connected to a pair of tracks. Each of the variable displacement motor/pump units includes a displacement controller for controlling the displacement of the motor/pump unit. To initiate a steering maneuver, a control signal is directed to the displacement controller of one of the motor/pump units to change the displacement of the motor/pump unit causing the track to slow down and start driving the motor/pump unit.

Abstract: A skid steering loader capable of performing on-the-spot rotation. The loader has a wheel-type handle, an accelerator pedal, and a drive lever for setting the loader to forward, neutral, and rearward positions. A control device receives a handle turn angle signal, an accelerator pedalling angle signal, and a drive instruction signal from the drive lever. The control device controls a drive mechanism for driving left and right wheels in response to these signals to thereby separately control the numbers of turns of and directions of rotation of the wheels. The skid steering loader can be operated by manipulating the accelerator, handle, and drive lever in same manner as an ordinary automotive vehicle.

Abstract: This invention provides a hydraulically driven crawler vehicle in which pilot pressure for controlling the discharge of right and left variable displacement pumps is produced in response to the engine speed by throttle valves disposed in the discharge oil circuit of a fixed displacement pump, variable throttle valve in a branch circuit each installed in a pilot circuit for controlling the right and left crawlers is operated by a cam rotated by the steering wheel, and when the steering wheel is turned exceeding a certain angle, a direction change-over solenoid valve of variable displacement pump at the steering wheel turning side is energized to the reverse side so that the right and left crawlers are driven in the reverse direction to each other.

Abstract: A track-laying vehicle has two tracks, each with a hydrostatic drive unit, where at least one drive motor 1, 2 adjustable in working volume is provided in each drive unit and to which at least one pressure medium supply line 3, 4, 5, 6 connected to a hydrostatic pump leads and which has a working volume adjusting device 9, 11, 10, 12 that can be influenced by a signal dependent on the operating pressure. To avoid unintentional changes in direction of the track-laying vehicle in the case of different resistances to the tracks, it is proposed to connect the pressure medium supply lines 3, 4, 5, 6 of all the drive motors 1, 2 to a shuttle valve circuit 32, 33, 34 which determines the highest of the operating pressures of the hydrostatic drive unit and empties in a signal line 19 that is connected to the control elements of the working volume adjusting devices 9, 11, 10, 12 of all the drive motors 1, 2.

Abstract: A hydrostatic drive system for vehicles including a hydromotor with a control unit forming together a drive unit which in the assembled state can be inserted in the seat of the centering device of the drive system, the configuration and arrangement of the wheel brake valve wakes possible to obtain a drive unit with compact dimensions, in axial as well as in radial direction, especially due to the double function of the wheel brake valve which serves simultaneously as a pressure relief valve.

Abstract: A utility vehicle having two steerable front wheels. Left and right-fluid powered rotary actuators have their bodies rigidly attached to the vehicle frame with their drive shafts attached to wheel brackets. The front wheels are each attached to one of the wheel brackets. Each actuator includes a pair of fluid ports, and a piston sleeve which reciprocates within the body of the actuator to rotate the drive shaft relative to the body through a range of at least 180.degree.. Fluid conduit interconnects the ports of the two actuators in series, and with a fluid-control steering valve. Operation of the valve selectively applies pressure to the piston sleeves of the actuators to simultaneously rotate their drive shafts and, thus, the left and right front wheels in unison and in substantially equal angular amounts through a steering range of at least 180.degree.. A motor provides drive to one of the front wheels to facilitate movement of the vehicle forward end when it is not desirable to drive the rear wheels.

Abstract: A steering system for a tracked vehicle extracts a portion of power from an engine which propels the vehicle, and combines the power with the remainder of the engine power by differential gear assemblies at the tracks of the vehicle for effecting a steering movement of the vehicle while the vehicle is being propelled in either the forward or reverse direction by the engine. The steering system includes a variable hydrodynamic torque converter coupled to the engine and outputting torque via a reversing gear set to an output shaft system having gears for constraining the output shafts to rotate in opposite directions. A clutch assembly is located outside of a housing which encloses the torque converter, and includes individual clutches which are selectively activated to couple forward or reverse rotation from the reversing gear set to the output shafts for selectively steering the vehicle in a right turn or a left turn.

Abstract: To override the vehicle immobilizing effect of a failed automatic ratio controller in a hydromechanical transmission, the conventional manually shiftable range selector is loosely linked with a ratio arm while the latter is being stroked by the controller to vary hydrostatic output speed. Upon controller failure, the range selector is drivingly linked with the ratio arm, such that shifting movements of the range selector are translated into stroking movements of the ratio arm to provide manual control of vehicle propulsion. Safeguards are provided to ensure that conversion between the normal propulsion mode governed by the automatic ratio controller and the override propulsion mode manually governed by the vehicle operator is effected in a safe manner.

Abstract: A transmission for a skid-steering vehicle having two tracks or two sets of wheels in which power is transferred from one or more prime movers to the tracks or wheels through a gearbox is proportional to the sum of the input speeds and the difference between the output speeds is proportional to the difference between the input speeds, the internal gearing of the gearbox consisting of two only differential gearing sets each comprising three elements within connections between two of the elements of one of the differential set with two of the elements of the other differential set. A fully hydraulic drive is preferably provided between the prime mover and hydraulic motors driving the gearbox.

Abstract: An apparatus for controlling the distribution of drive power in a motor vehicle includes a pair of pressure regulating valves, a pair of regulated pressure passages interconnecting the pressure regulating valves, respectively, and torque transmission clutches which transmit drive power to a pair of drive wheels, and a shut-off valve mechanism disposed between the regulated pressure passages for selectively bringing the regulated pressure passages into and out of each other.

Abstract: Improved steering systems are provided for skid-steering vehicles such as military tanks, track-type tractors and the like. A diesel engine may be used to rotate a drive shaft interconnected by port and starboard planetary gear assemblies, to apply driving power simultaneously to both track-drive mechanisms. Steering is provided by port and starboard hydraulically-actuated motors, each positively interconnected with the ring gear or other suitable component of its respective planetary gear assembly, whereby each track-drive mechanism may be controlled separately and independently of the other.

Abstract: An apparatus is disclosed for controlling at least two driven wheels of a vehicle. The apparatus includes two hydraulic motors, each motor drivably connected to an associated drive wheel. A load sense piston pump provides a source of pressurized fluid for operating the hydraulic motors. Associated with each hydraulic motor is an electrically controllable load sense flow control valve assembly, an electrically controllable directional control valve, and a set of counterbalance valves. A microcomputer controls operation of the electrically controllable load sense flow control valve assemblies and the electrically controllable directional control valves in response to electrical signals indicative of rotary position of a steering wheel, position of an operator controlled speed and direction input device, and the speed of the vehicle engine. Steering ratio can be selected by the operator. Vehicle speed is controlled so as to prevent pump cavitation and engine stalling.

Abstract: A drive unit including an engine and steerable wheels, is pivotally connected to the forward end of a chassis, including a body and ground support wheels. A pair of struts movably mounted to the chassis, equilaterally outboard and above the pivotal connection, extend downwardly inward to the drive unit and are movably affixed. In response to the natural tilt of the chassis while transversing a corner, weight is transferred through the struts to equalize traction upon the steerable wheels.

Abstract: A two row harvester running gear is of a tricycle type with all wheels being hydraulically driven and with a center rear wheel that is steerable and smaller than the two front wheels. The running gear configuration provides sharper turns in muddy fields without bulldozing, and space for side mounting pilers adjacent the front wheels and inboard of them to minimize the number and degree of changes of direction in cut cane travel. Closed loop and parallel connections of an hydraulic power system rotates all wheels for a common linear speed, and at torques relative to the size and positioning thereof for maximum traction.

Abstract: A motor vehicle having a pair of front drive wheels and a rear steerable drive wheel mounted on a main frame. A sub-frame secured to the main frame intermediate the front and rear drive wheels carries an internal combustion engine and a pump assembly. The pump assembly has a first pump operable to deliver fluid under pressure to fluid operated motors operably connected to the front drive wheels and a second pump operable to deliver fluid under pressure to a fluid operated motor operably connected to the rear drive wheel. The internal combustion engine and pump assembly are located below a seat and floor with both the engine and pump assembly positioned transversely of the main frame of the vehicle. The rear wheel is mounted on the frame for angular movement about a generally upright axis. A fluid operated double acting piston and cylinder assembly operates to angularly move the rear wheel about the upright axis to steer the vehicle.

Abstract: A hydraulic fluid drive for a land motor vehicle having front and rear drive wheels. An internal combustion engine drives a pair of positive displacement pumps. A first pump is connected to hydraulic motors that drive the front wheels of the vehicle. A second pump is connected to a hydraulic motor that drives a rear steerable wheel of the vehicle. A manually operated control is used to adjust the speed and torque of the motors for the front wheels. A front and rear wheel drive equalizing control operates in response to differences in hydraulic fluid pressure supplied to the front and rear hydraulic motors to equalize the fluid pressure pumped to the front and rear hydraulic motors so as to maintain the torque and speed of the front and rear wheels substantially constant. A foot operated lever is used to operate the control for the first pump for changing the supply of fluid pressure to the front wheel motors.

Abstract: A steering assist device for a vehicle of the type having a pair of drive wheels in which steering is accomplished by applying differential hydraulic flow to the drive wheels and a non-driven castor wheel. The steering assist device includes a power cylinder for rotating the non-driven castor wheel about a vertical axis, a device for sensing or providing access to the hydraulic pressure driving the drive wheels and a control device for controlling the actuation of the power cylinder in response to the hydraulic pressure driving the drive wheels in such a way that the non-driven castor wheel is rotated to assist the drive wheel being driven by the greater hydraulic pressure.

Abstract: A hydraulic drive and braking system for vehicles having a pair of positive displacement pumps connected to drive axles attached to the wheels of the vehicle. Hydraulic fluid is supplied to the positive displacement motors from a reservoir by means of a variable displacement pump. The flow to the motors is controlled by a flow divider connected to the steering linkage. Braking is provided by blocking the return flow of the positive displacement motors. An antiskid system senses wheel rotation and responsive thereto prevents the blocking of the return flow of the positive displacement motors.

Abstract: A tricycle frame is elongated to carry a sprayer or a fertilizer spreader, or the like. Two transversely spaced rear wheels engage the ground at the rear of the frame and are independently driven by hydraulic motors. A ground engaging front wheel, also independently driven by a hydraulic motor, steers the vehicle. The front wheel is carried on a steering post including a vertical spindle journaled on a framework extending forwardly from the main frame. A cantilever mounted on the steering post projects forwardly beyond the steering wheel and downwardly. On its forward end the cantilever supportsa cab housing the operator and the controls of the vehicle. The cantilever construction not only enables the cab to achieve a low profile but allows the cab to swing laterally well in excess of the movement of the steering wheel, thereby affording a clear rear view to the operator in the cab whenever required.

Abstract: A vehicle with a total power fluid system includes a pair of drive wheels, variable displacement, fluid motors driven by an engine driven, variable displacement, fluid pump. The motor displacements are controlled by operator speed input and speed sensing controls, and the pump displacement is controlled by a pressure sensing pressure control. A vehicle steering control includes an operator steering input control connected to a steerable wheel control for actuating a valve for holding, turning, or castering fluidly steerable wheels which are capable of turning the vehicle. The operator steering input control is further connected to the operator speed input controls to slow the turn-side drive wheel motor during either a steerable wheel controlled or an emergency, drive wheel controlled turn. During either an electrical failure or a hydraulic failure sensed by the inability of the steerable wheels to follow the operator steering input control, the valve will be actuated to caster the steerable wheels.

Abstract: A hydrostatic transmission control for a hydrostatic transmission having a variable displacement pump and a variable displacement motor including pressure-responsive displacement control means for the pump and motor with a displacement control valve for each of the pump and motor and positionable by a control pressure to set the displacement of the pump or motor with which it is associated. In dual path control of two hydrostatic transmissions, a master circuit has a first valve for setting a control pressure to determine the speed of operation of the transmissions and a second valve for determining the direction of operation of the transmissions, with operation of both valves by a single control handle. The master circuit connects into two branch circuits, each leading to the displacement controls for one of the hydrostatic transmissions and with each branch circuit having its own steering control valve.