Abstract: A vehicle including a variable gear ratio steering device and an electric power steering apparatus is disclosed. The variable gear ratio steering device influences on a steering system of the vehicle and varies a ratio of a steering angle of steerable road wheels to a steering wheel angle by driving an electric motor in accordance with a vehicle speed. The electric power steering apparatus influences on the steering system of the vehicle and provides an assist steering wheel torque by driving an electric motor in accordance with a manual steering wheel torque. The vehicle comprises a power supply voltage detector for detecting a voltage of a power supply, and a control unit for controlling the electric motor of said variable gear ratio steering device in accordance with the detected voltage. When the detected voltage decreases to a certain voltage or lower, the control unit brings the variable gear ratio steering device into a slow state and thereafter stops the same.

Abstract: The invention relates to a steering system for a motor vehicle having at least one steerable wheel, an actuator and a superposing gear assembly. The steering movement, which is initiated by the driver of the vehicle, and the movement, which is initiated by the actuator, are superposed by the superposing gear assembly for generating a steering movement of the steerable wheel within pregiven steering stops. The essence of the invention is that the movement, which is initiated by the actuator, is at least reduced before reaching the steering stop. According to the invention, one arrives at a superposed steering with which the steering stops are considered so as to provide increased safety and increased comfort.

Abstract: The vehicle rack and pinion steering system has an elongated rack bar. Tie rod connectors are provided on the ends of the bar. A rack gear teeth section is provided on the rack bar in a position parallel to and spaced from the rack axis. A cylindrical bearing surface is on the opposite side of the rack axis from the rack gear teeth section. The bearing surface has a fixed radius and is concentric with the rack axis. The rack section width is at least twice the fixed radius. Secondary bearing contact surfaces join the bearing surface, extend toward the rack gear teeth section and diverge from each other. Contact between the bearing and surface shifts the point of convergence of forces on the rack toward the pitch point.

Abstract: The invention relates to a hydraulic steering device for the chassis of a vehicle, in particular of a crane or transport vehicle, with chassis axles steerable between longitudinal and transverse drive positions and in each case fixed to a shaft on the vehicle that is pivoted about a vertical swiveling axle, on which shaft a steering cylinder acts by way of at least one laterally projecting control arm for swiveling of the shaft. The steering cylinder acting on the projecting control arm and a further steering cylinder acting on a vehicle frame beam are articulated to a lever arm, coaxially pivoted on the shaft, in such a way that the torsional movement of the shaft resulting from the retracting and extending movement of the two steering cylinders adds up to at least ±90°.

Abstract: A center take-off type power steering apparatus having a gear housing and a power cylinder positioned regarding a rotation direction of the power cylinder about a common center axis of the both by a pin forcibly fitted into one of the gear housing and the power cylinder, the gear housing and the power cylinder being fixed regarding the axial direction of the power cylinder by causing a stopper ring provided at one of the gear housing and the power cylinder and a lock nut screwed to the other thereof to abut on each other.

Abstract: The entire right, title and interest in and to this application and all subject matter disclosed and/or claimed therein, including any and all divisions, continuations, reissues, etc., thereof are, effective as of the date of execution of this application, assigned, transferred, sold and set over by the applicant(s) named herein to Deere & Company, a Delaware corporation having offices at Moline, Ill. 61265, U.S.A., together with all rights to file, and to claim priorities in connection with, corresponding patent applications in any and all foreign countries in the name of Deere & Company or otherwise.

Abstract: To keep low the cross frequency of current feedback control and provide a good steering feeling, a first operation expression is selected when a difference &xgr; between a current instruction value computed based on a steering state of a steering wheel and a traveling state of a vehicle and a motor drive current value supplied from a battery to a motor for providing assist force to a system for transmitting power from the steering wheel to the wheels is larger than a predetermined value Th1, a second operation expression is selected when the difference &xgr; is smaller than the predetermined value Th1, and the difference &xgr; is corrected using the selected operation expression.

Abstract: A multi-wheel-driving vehicle including at least three parallel axles each of which is provided on both ends thereof with respective drive wheels and including power dividing means for permitting the rotary speed among the axles, is improved in its effect of braking so that the braking force of fewer brakes is effectively transmitted to all drive wheels of a vehicle according to a simple braking operation by a driver. The power dividing means, for example, a differential gear unit, includes an input member and a pair of output members, like differential side gears, each of which interlocks with at least one of the axles so as to differentially share a driving force received by the input member between the pair of output members.

Abstract: In an electrically operated power steering device wherein a rotational shaft of an electric motor is rotationally driven so as to apply a steering assist force to a steering shaft, a stator of the electric motor is provided with teeth portions composed of electromagnetic steel plates, coils wound around the teeth portions, and a yoke portion made of a magnetic substance that accommodates the coils and the teeth portions and can be utilized as a housing. Hence, the electrically operated power steering device can be made simple and compact, and it is possible to ensure running stability of the vehicle appropriately (i.e., to prevent swinging motions in response to a force inputted from the steering wheels).

Abstract: A device for determining the angular position of the steering wheel in a motor vehicle uses a steering angle sensor and an electronic evaluation device for determining the angular position. The steering angle sensor is integrated in a contact unit for transmitting energy and data from stationary subassemblies of the vehicle to the steering wheel and vice versa. Preferably, the steering angle sensor is disposed as part of a stator and rotor in a contact unit which operates in a contactless manner and comprises the stator and the rotor. In this way, the steering angle sensor does not require any additional space for installation and costs are reduced.

Abstract: An electromechanical steering actuator for a steer-by-wire application in motor vehicles. An electronic closed-loop/open-loop control system generates steering signals for a pair of electric servomotors, which act via a gear unit on a steering control element of a rack-and-pinion steering system. The closed-loop/open-loop control system includes a pair of process computers which deliver corrective signals to the servomotors via drive units. The steering actuator is divided into two diversely redundant systems including two redundant process computers, each of which delivers corrective signals via two redundant drive units to two servomotors which act on a common steering shaft.

Abstract: A steering cylinder retention system is provided that replaces the conventional bolted joint with a pin and snap ring arrangement that requires fewer parts and is easier to assemble. The retention system provides a pair of annular axle brackets whereby the steer cylinder is received in both axle brackets. The steer cylinder is retained in the axle brackets by a shoulder, pin and snap ring assembly. More specifically, the steer cylinder is formed with a seating shoulder that abuts one of the axle brackets, and a slot is provided between the cylinder and axle bracket to prevent rotational movement of the cylinder with respect to the axle bracket. A snap ring arrangement fastens the cylinder against axial movement with respect to the axle cylinder.

Abstract: In a control device for influencing the driving dynamics of four-wheel vehicles, the vehicle lengthwise speed and the steering angle are introduced as input signals and control signals are generated that act on positioning devices for adjusting the vehicle wheels. In order to set and adjust the transverse dynamic properties of a vehicle with a low cost of construction in normal driving, for setting a desired driving behavior, target values may be specified for the steering ratio, the self-steering gradient, and the float angle gradient as set signals from which steady-state additional trail angles can be determined which can be supplied as control signals to the positioning devices.

Abstract: A gearbox monitoring apparatus is disclosed for use in combination with a gearbox (4) which provides a connection between an input shaft (3) driven by a motor (1) and an output shaft (2), said gearbox monitoring apparatus comprising a first position sensing means (11) and a second position sensing means (12), said first and second position sensing means generating a respective first and second output signal, said first output signal being representative of the angular position of the input shaft and said second output signal being representative of the angular position of the output shaft, a torque signal generating means (6) which generates a third output signal representative of the torque carried by the gearbox (4), and signal processing means (15) adapted to receive said output signals and to process said output signals to produce one or more modified output signals representative of the wear in the gearbox.

Abstract: A steering gear box mounting structure has a flexible support device for mounting a steering gear box to a vehicle body member and a flexible support device mounting portion for mounting the flexible support device to the steering gear box. The flexible support device is composed of an outer sleeve, an inner sleeve and an elastic body. The outer sleeve is conically shaped in its both axial end portions and is cylindrically shaped in its center portion. The inner sleeve is partially conically shaped in its axial end portions and is cylindrically shaped in its center portion. The elastic body is interposed between the outer and inner sleeves with a hollow space left therebetween. In the flexible support device, the outer sleeve is provided with an inclined surface inclined with respect to a direction perpendicular to the axis of the outer sleeve.

Abstract: An electric power steering control system reducing steering torque without making a driver feel uncomfortable torque oscillation, including a rotation speed observer for estimating the rotation speed of a motor based on the output of a torque sensor high pass filter (HPF) and the output of a drive current HPF obtained by removing a steering frequency component from a drive current detection value.

Abstract: In a wire-type steering device in which a steering wheel and a gear box are connected to each other by wires, one end of each inner cable of two Bowden wires are wound around a driving pulley which is mounted on a rotary shaft of a steering wheel. The inner cables are inserted through the inside of outer tubes fixed at their corresponding ends to a driving pulley housing. The direction of drawing of the Bowden wires from the driving pulley housing is offset at an angle .alpha. in a forward direction of a vehicle body relative to a plane perpendicular to the rotary shaft 12, thereby preventing the Bowden wires from being exposed inside of a vehicle compartment, and/or from interfering with an instrument panel and the like.

Abstract: An electric power steering control for a motor vehicle reduces motor torque ripple and road generated disturbances communicated to the vehicle handwheel while promoting system stability. In deriving an output command torque signal to the EPS motor, the control (1) derives an electric motor speed signal, (2) differentiates the electric motor speed signal, (3) stores a schedule of gain as an increasing function of electric motor torque, (4) modifies the differentiated estimated electric motor speed signal in response to the gain to provide a damping correction value and (5) derives the output command signal responsive to the damping correction.

Abstract: A cable steering device is provided such that it can be easily and reliably confirmed whether an inner cable of a Bowden cable is precisely wound around a pulley housed in a housing. Two inner cables are wound around a helical groove defined in an outer peripheral surface of a driven pulley connected to a steering wheel through a driven shaft. An opening is defined in a driven pulley housing enclosing the driven pulley, so that when the steering wheel is assembled to the driven shaft by a spline, it can be confirmed from the outside that the two inner cables have been wound precisely in two turns around the driven pulley.

Abstract: Operation of a steering wheel is transmitted to a steering gear box through two cables. In this cable-type steering device, a steering torque inputted to the steering wheel is detected by a steering torque detector provided between the steering wheel and the cables. The operation of a motor for a power steering operation for driving the steering gear box is controlled on the basis of the detected steering torque. The steering torque detected by the steering torque detector includes the friction of the cables and hence, a steering torque offsetting the friction of the cables can be generated in the motor for the power steering operation, thereby providing an appropriate steering feeling. A hydraulic power steering device may be used instead of or in addition to a motor for a power steering operation.

Abstract: A steering system for a vehicle is provided in which each of the inner cables of two Bowden wires has one end thereof wound around and fixed to a driving pulley provided on a rotary shaft of a steering wheel, and the other end thereof is connected to a follower pulley. Spring sheets provided at end of outer tubes of the Bowden wires, are biased by springs and are connected to differential transformers. When a difference in tension corresponding to steering torque is generated between the two inner cables, the spring sheets are moved relative to each other, and a steering torque is determined based upon the amount of relative movement detected by the differential transformers. Thus, the steering torque inputted to the steering wheel can be correctly detected, while eliminating the influence of friction of the Bowden wires.

Abstract: A power steering apparatus for an electric vehicle has a steering mechanism for steering a pair of steered wheels upon receiving assist power from a steering assist-power according to a steer force required for steering the steered wheels. A fluid pressure pump driven by an electric motor supplies pressurized fluid to the steering assist-power mechanism. An electric motor controller stops the electric motor when the electric-source voltage detected by an electric source voltage detector is greater than or equal to a voltage set value and when the steer angle detected by a steer angle detector is smaller than a steer angle set value, and prohibits stopping the electric motor when the electric-source voltage is smaller than the voltage set value. Therefore, it becomes possible to ensure the steering responsiveness under an electric voltage lowered condition while avoiding the disturbance to the electric source.

Abstract: A power steering device capable of facilitating assembling thereof and eliminating a variation in elastic force acting on an input shaft of the power steering device. Leaf spring structures each of which includes a first leaf spring and a second leaf spring are arranged. The first leaf spring includes a spring-side support section constituted by a V- or U-shaped groove, a pair of rolling surface sections arranged so as to be contiguous to the spring-side support section and outwardly extend from both ends of the spring-side support section, a pair of support leg sections each arranged so as to be contiguous to each of the rolling surface sections and outwardly extend therefrom, and a pair of holding sections each arranged so as to be contiguous to each of the support leg sections and outwardly extend therefrom. The holding sections each are pressedly contacted with press contact surfaces or side surfaces of a spring receiving chamber, resulting in the first leaf spring being securely held.

Abstract: A cable-type steering device for controlling operation of a power-steering motor in accordance with the tension on stranded metal wire cables which connect a vehicle steering wheel to a steering gearbox. Tensions of the cables are detected by contact with an arm of a potentiometer. The surfaces of the cables are smoothed by a swaging treatment or resin coating treatment to prevent undesirable vibrations of the arm of the potentiometer and improve the detection accuracy of the potentiometer. The smoothing treatment eliminates undesirable vibration which might otherwise occur due to irregularity of the surface of untreated stranded metal wire cable.

Abstract: A sensing device conveniently and accurately produces electrical signal representative of the direction in which he steerable wheels (10 and 11) of a vehicle are pointing and the rate of change of the direction of the steerable wheels. The device includes a circular or donut-shaped magnet (26) that is attached to the pinion (12) of a rack and pinion steering gear (6). The magnet has a plurality of magnetic poles (28) spaced around its circumference and preferably extending axially through the magnet. As the magnetic poles rotate past a plurality of sensors (36 and 38) that are located in quadrature positioning relative to the magnetic poles and to each other, the sensors generate electrical signals that are processed to determine the rotation direction of the pinion and the rate of such rotation.

Abstract: A power steering apparatus having enhanced neutral rigidity and improved operation stability at the time of straight traveling. The apparatus includes a pair of spring members which sandwich an input shaft and are disposed in an output shaft or a member rotating integrally with this output shaft. A preset force is exerted by a spring force of the spring members.

Abstract: A front suspension unit for the independent suspension of the front wheels of a motor powered off road four wheel vehicle comprising a pair of suspension units with their outer casings mounted together and the inner members carrying laterally extending arms with their free ends constituted for attachment to front wheel mounting assemblies and such units in combination with a steering assembly having a column to be supported at one end from the vehicle chassis and carrying a steering wheel and axle on the other end, the axle having a chain and sprocket mounted thereon with the ends of the chain attached to a plate rotatably mounted on the column and carrying link arms to be attached one to each of the front wheel mounting assemblies.

Abstract: A method for determining a steering wheel angle of a vehicular steering system includes determining a center position for the steering sensor output every time the vehicle is started. The method employs the use of a yaw sensor for computing an estimate of the actual steering position so that a center position may be back computed to provide immediate and accurate steering position data using the steering sensor signal for controlling an automotive device. The accuracy of the initial estimates may be improved upon by implementing interim and final center algorithms as vehicle operating characteristics permit.

Abstract: An arrangement of circuit casings and circuit boards in a motorized power steering device including a drive circuit casing, a control circuit casing and a gear casing connected to the drive circuit casing. The drive circuit casing includes a drive circuit board provided thereon with a drive circuit whereas the control circuit casing includes a control circuit board provided thereon with a control circuit for outputting a control signal to the drive circuit. An electric motor is attached to the drive circuit casing such that the drive circuit casing is interposed between the gear casing and the electric motor.

Abstract: A method for determining a steering wheel angle of a vehicular steering system includes determining a center position for the steering sensor output every time the vehicle is started. The method employs the use of a yaw sensor for computing an estimate of the actual steering position so that a center position may be back computed to provide immediate and accurate steering position data using the steering sensor signal for controlling an automotive device. The accuracy of the initial estimates may be improved upon by implementing interim and final center find algorithms as vehicle operating characteristics permit.

Abstract: In a press fit arrangement of a tubular nut member in an enlarged end portion of a hollow shaft, typically used in an electric power steering device, a region of loose fit is provided in a part of an interface between the tubular nut member and the enlarged portion, adjacent to an annular shoulder defined at the inner boundary of the enlarged portion. The region of loose fit can be achieved by provided an annular recess in the inner bore of the enlarged portion and/or the outer circumferential surface of the nut member. Thereby, the region of a relatively high rigidity, which is created by the provision of the annular shoulder, is prevented from being involved in the press fit when the nut member is fitted into the inner bore of the enlarged portion until the inner end of the nut member abuts the annular shoulder so that a relatively uniform tight fit can be achieved between the nut member and the enlarged portion over a relatively large axial length.

Abstract: An amphibious vehicle having a pontoon assembly including a pair of pontoons and a set of wheels operably attached to the pontoons which are pivotally coupled to a vehicle frame structure such that the pontoons are positionable between a raised position whereby the wheels are deployed for providing land travel and a lowered position whereby the pontoons are deployed for providing marine travel. A pivot assembly interconnects the pontoon assembly to the frame structure. The amphibious vehicle further includes an engine, a jet propulsion unit and a drive train for selectively transmitting torque generated by the engine to the wheels for propelling the amphibious vehicle during land use and to the jet drive for propelling the amphibious vehicle during marine use. A mechanical steering interlock positively connects and disconnects the steering of the set of wheel when the pontoon assembly is positioned in the raised and lowered positions respectively.

Abstract: The apparatus for determination of absolute angular position of a steering wheel (w) rotatable through several revolutions includes a fine code disk(2) nonrotatably attached to the steering column (c) and provided with circumferentially distributed code elements (2',2", 2'", . . . ) and circumferentially distributed code element sensors (5) for sensing the code elements (2", 2", 2"', . . . ) to generate fine signals which repeat after each revolution of the steering wheel and are indicative of a relative steering wheel angular position during each revolution; and a coarse code disk (7) provided with at least three code tracks (A,B,C, . . . ) and at least three code track sensors (8a, 8b, 8c , . . . ) for sensing respective code tracks (A,B,C, . . . ) to generate a progressive 3-bit coded signal indicative of the absolute steering wheel angular position over the several revolutions.

Abstract: A hydraulic power steering system has a servo valve which is arranged between the delivery and suction side of a hydraulic pump. The servo valve is open in the central or normal position and controls the pressure to at least one connection of a hydraulic servomotor. When an operating element of the power steering system is actuated, the servomotor serves to generate a servo positioning force which facilitates the adjustment of the operating element. The hydraulic pump has a drive which can be switched-off, or can be switched over to an extremely low capacity or standby operation, when no servo positioning force is required.

Abstract: Transducer structure for a steerable axle includes a transducer assembly having a housing and a cup-shaped journal, having an apertured bottom portion, fixed to the spindle of a steerable wheel by the spindle bolt for rotation with the spindle about the spindle axis. A bracket connected to the guide axle knee nonrotatably supports housing structure above the spindle, and the journal is rotatably received within a bearing and seal in the housing structure. The journal includes apertures which receive mating pins which constrain the rotary member for rotation with the journal relative to the housing structure. A special fixture supported by the tie-rod bolt accurately centers the journal during assembly and facilitates calibration of the transducer.

Abstract: A rack steering system for motor vehicles has inner track rod joints which are offset transverse to the longitudinal axis of the rack. The inner track rod joints are arranged on separate deflection levers which are, in turn, drive-connected to a central tap-off connection of the rack by connecting struts.

Abstract: An axial mounting of a rack-and-pinion steering system takes transverse forces and, at the same time, permits a defined resilience of the rack mounting in the transverse direction of the vehicle for affecting steering behavior of the vehicle and, in particular, permitting desired understeer during cornering. Mountings of this kind are particularly applicable to passenger vehicles in which the track rods are arranged behind the steered axle in the direction of travel. The rack-and-pinion steering system is mounted by two bearings arranged upright and at a relatively great distance from one another at the ends of the steering gear casing. The bearing bodies are either V-shaped or Y-shaped as viewed in longitudinal section.

Abstract: A steering axle includes a reversible axle beam assembleable with a pair of steering knuckle assemblies in one orientation providing a first range of maximum steering angles and in a second, reversed orientation providing a second range of maximum steering angles. The axle beam includes an elongated structure with two ends, each adapted to carry a steering knuckle assembly that is pivotably rotatable about a steering axis by a steering arm. Each end of the axle beam includes a pair of stops formed integrally therewith. The two stops within each pair are disposed across the longitudinal centerline of the axle from each other and at two distinct distances along the axle beam.

Abstract: An improved riding lawn mower includes a vehicle frame having a front end, a rear end, and a rear motor deck that is secured to the rear end of the frame. A drive motor is mounted above the motor deck while a rear wheel assembly engaged with the motor, is connected to the bottom of the rear motor deck. The mower also includes a front wheel assembly connected to the front end of the vehicle frame. A vehicle body and driver's seat are attached to vehicle frame. A steering column is cooperatively connected at its lower end to the front wheel assembly and includes at its upper end, a steering wheel positioned within reach of the operator seated on the mower. A steering mechanism is linked between the lower end of the steering column and the front wheel assembly. The steering mechanism is positioned above the front wheels of the mower and turns the front wheels asynchronously so that the lawn mower can be driven along an arc path having a radius approximately half the length of the vehicle frame.