Abstract: The present invention relates to an apparatus (10) for helping to turn steerable wheels (15) of a vehicle. The apparatus includes a hydraulic power-assisted steering gear (130), a fluid source (20) for supplying the steering gear (130) with hydraulic fluid, and a controller (52) for controlling the fluid source. The steering gear (130) includes a closed center valve (150) operatively connected with a vehicle steering wheel (12) and in fluid communication with the fluid source. The controller (52) is responsive to the pressure of the hydraulic fluid for controlling the fluid source (20) to supply the steering gear (130) with hydraulic fluid at a first predetermined pressure when the vehicle is in a first condition. The controller (52) is responsive to the pressure of the hydraulic fluid for controlling the fluid source (20) to supply the steering gear (130) with hydraulic fluid at a second predetermined pressure when the vehicle is in a second condition.

Abstract: A steering system for a machine having at least one steerable traction device is disclosed. The steering system may have a steering actuator operatively connected to the at least one steerable traction device, and a travel speed sensor configured to generate a signal indicative of a travel speed of the machine. The steering mechanism may also have an operator input device having a deadzone. The deadzone may vary in response to the signal. The steering system may also have a controller in communication with the steering actuator, the operator input device, and the travel speed sensor. The controller may be configured to affect operation of the steering actuator in response to operation of the operator input device only when the operation of the operator input device deviates from the deadzone.

Abstract: In a power steering system, the steering state of wheels is detected based on the steering speed to judge as to whether the steering state is in turning of the steering wheel or holding of steering speed is the steering wheels. At the time of the steering operation state, the control is executed so that a difference between a torque command value to an electric motor and the actual torque thereof will become smaller. Also, at the time of the holding operation state, the control is executed so that a difference between the revolution speed of the electric motor and a revolution-speed command value thereto will become smaller.

Abstract: In a hydraulic power steering apparatus, hydraulic pressure for generating steering assist power is varied by varying opening of a variable throttle portion by movement of a spool. The spool is disposed in a provisional origin by driving a stepping motor in one direction according to a number of steps for setting provisional origin from a position at a time of start of control, and the number of steps at a time of completing of the driving is set to a provisional origin for calculation. In a return to origin permission state where the spool is disposed in a provisional origin and the number of steps from the provisional origin for calculation is zero, a number of steps at a time when the driving of the stepping motor according to a number of steps obtained by subtracting the number of steps for setting provisional origin from a number of steps for setting origin is completed is set to an origin for calculation, and the movement of the spool is stopped at the origin with a stopper.

Abstract: An apparatus (10) for turning steerable wheels (12, 14) of a vehicle in response to turning of a steering wheel (18) of the vehicle. The apparatus includes a hydraulic power steering gear, which does not include a rotary valve responsive to a steering input generated by turning of a steering wheel (18). The hydraulic steering gear includes a first chamber (96) for holding hydraulic fluid and a second chamber (98) for holding hydraulic fluid. An increase in fluid pressure in one chamber acts to turn the steerable wheels (12, 14) of the vehicle in one direction and an increase in fluid pressure in the other chamber acts to turn the steerable wheels (12, 14) in a direction opposite the one direction. The apparatus (10) includes a variable flow mechanism (50) for supplying a flow of hydraulic fluid to the first and second chambers (96, 98), which flow varies in dependence upon at least one sensed vehicle condition.

Abstract: A hydraulic steering device (1) of a mobile machine, in particular of an industrial truck, includes a steering angle transmitter (2) in mechanically functional communication with a steering valve (4). As a function of the actuation of the steering angle transmitter (2), the steering valve (4) controls the connection of a steering drive (13) with a pressure fluid source (6) and a reservoir (11). To vary the translation ratio of the steering device in a simple manner, a bypass device (20) is operationally associated with the steering drive (13). By activation of the bypass device, the quantity of pressure fluid delivered from the pressure fluid source (6) to the steering drive (13) can be diverted to a reservoir (11).

Abstract: An electric power steering device that can estimate an ambient temperature and apply current limiting without using ambient temperature detecting means is provided. The electric power steering device includes a motor that supplements the driver's steering force, a controller that determines and controls the quantity of current passed to the motor, and vehicle speed detecting means. The electric power steering device includes ambient temperature estimating means provided with a vehicle speed signal input from the vehicle speed detecting means and limits the quantity of current passed to the motor according to an output from the ambient temperature estimating means.

Abstract: System for controlling at least one hydraulic cylinder (2, 3) having a first control valve unit (4) connected to the hydraulic cylinder for regulation thereof. A first operable control means (5) is included and which is adapted for controlling the first control valve unit. A second control valve unit (6) is also included that is connected to the hydraulic cylinder for regulation thereof, and a second operable control means (7) is further provided and which is adapted for controlling the second control valve unit. The system also includes means (23) for prioritizing the first control means. The prioritizing means (23) is controlled via hydraulics in such a way that the effect of the second control means (6) on the regulation of the hydraulic cylinder (2, 3) is at least substantially reduced as soon as the first control means (5) is operated.

Abstract: A priority valve 7 is disposed between a hydraulic pump 2 and a steering valve 4 and is used to supply priority steering cylinders 103a and 103b with pressurized oil discharged from the hydraulic pump 2 by controlling the differential pressure across a meter-in hydraulic line of the steering valve 4 such that the differential pressure is kept at a target value. A pressure sensor 31 for detecting the load pressures of the steering cylinders 103a and 103b is provided. On the basis of the detected load pressures, the target value set for the priority valve 7 is modified by devices including a controller 32, a solenoid valve 33, a pilot hydraulic line 29, and a pressure receiving unit 24c of the priority valve 7. The above configuration enables suppression of a shock occurring at the start of turning of the steering wheel.

Abstract: A steering apparatus for an automotive vehicle is provided with an electric drive unit that varies a steering ratio between a road wheel angle and a steering wheel angle of the vehicle, a temperature sensor that detects a temperature of the electric drive unit, and a control unit including a steering ratio characteristic setting block that sets a characteristic of the steering ratio including a steering gain and a steering response rate in accordance with an operating state of the vehicle and, when the temperature of the electric drive unit exceeds a first temperature threshold, adjusts the steering response rate in such a manner that the steering response rate comes closer to a base steering response rate level as the temperature of the electric drive unit becomes increased and a drive block that drives the electric drive unit to vary the steering ratio according to the steering ratio characteristic.

Abstract: In a power steering device employing a hydraulic power cylinder, a motor-driven pump, and a driving power source for the motor, a power steering control system is configured to electrically connected to at least the motor and the power source for controlling a driving state of the motor and a power source voltage of the power source. The power steering control system includes a motor control circuit that generates a motor driving signal, whose command signal value is determined based on a steering assist force applied through the power cylinder to steered road wheels, a booster circuit that boosts the power source voltage, a motor angular acceleration detection circuit that detects or estimates a motor angular acceleration, and a booster-circuit control circuit that controls, responsively to the motor angular acceleration, switching between operating and non-operating states of the booster circuit.

Abstract: A hybrid electrical power assist system (EPAS) for an automotive vehicle that utilizes the advantages of a conventional EPAS system to provide power assist based upon several distinct sensor inputs, in a heavy duty vehicle that requires significantly more assistance forces than a conventional EPAS can provide. The hybrid system utilizes a hydraulic amplifier that is connected to receive the torque output from an EPAS motor actuator and responsively provide a fluid under differential pressure through a pair of high pressure lines to a steering piston.

Abstract: There is provided a power steering system including an electric motor for generating a steering force in response to an command value, and a controller for generating the command value to the electric motor. Here, the controller generates the command value in correspondence with steering state of wheels, thereby controlling torque or rotation number of the electric motor.

Abstract: An electronically controlled hydro-mechanically coupled power steering system includes a double-acting power cylinder having a directional control under-lapped four-way open center valve and a motor driven pump. A controller selectively provides pressurized fluid to the double-acting power cylinder to function in the manner of an inherently failsafe EPS system.

Abstract: A hydraulic servo-steering device includes a pump and a pump drive motor. At least one defined high power stage (C) and one defined low power stage (B) are provided in which the motor is selectively operated. Moreover, a defined additional power stage (A) is provided for the motor, in which the speed of the motor is reduced with respect to the low power stage (B). According to a method for controlling the pump drive motor of the hydraulic servo-steering device, the motor is operated in the additional power stage (A) under certain conditions which rule out an impairment to driving safety.

Abstract: A power assist steering system for a vehicle, especially for a truck or commercial vehicle, is disclosed that includes a mechanical engine-driven power steering pump that pumps hydraulic fluid to a power steering unit, and an electrical pump adapted to pump hydraulic fluid so as to optimize a power steering flow to the power steering unit and to minimize internal pump flow.

Abstract: An electronic control unit monitors pressure conditions present at the input to the steering system and other vehicle data signals and then provides override control of a hydro-mechanical flow control device. An electro-hydraulic valve is connected to the supply side of the hydro-mechanical flow control device and reacts to the electronic monitoring of pressure and other vehicle data to alter the counter-balancing forces within the hydro-mechanical flow control device. This causes a by-pass diversion of steering fluid to the source by the hydro-mechanical flow control device and thereby relieves backpressure on the pump when relatively little steering assist is required to be provided by the steering system. The control of steering fluid diversion at such times results in a significant reduction in parasitic losses within the steering system and improves the operating and fuel efficiency of the vehicle.

Abstract: An hybrid four wheel drive system characterized by a vehicle having a conventional rear wheel driveline as well as a conventional driving front steer axle powered by an hydraulic motor. The hybrid four wheel drive system is provided in multiple embodiments, particularly with and without an hydraulic pressure accumulator.

Abstract: A power steering apparatus includes a power cylinder including first and second pressure chambers; a reversible pump including a first outlet port and a second outlet port; a first hydraulic passage including a portion made from an elastomer; a second hydraulic passage including a portion made from an elastomer; a motor arranged to drive the reversible pump; a motor control section; a pump reverse rotation judging section configured to judge a reverse rotation state of the reversible pump when an actual rotation direction of the reversible pump does not correspond to a direction in which the motor is rotated by the driving signal from the motor control section; and a damping torque adding section configured to damp a torque generated in the reversible pump when the pump reverse rotation judging section determines the reverse rotation state of the reversible pump.

Abstract: A power steering apparatus includes a power cylinder; a reversible pump; first and second hydraulic passages; a reservoir tank; a first supply passage arranged to supply the hydraulic fluid through the reversible pump to the second hydraulic passage; a first one-way valve provided in the first supply passage; a second supply passage arranged to supply the hydraulic fluid through the reversible pump to the first hydraulic passage; and a second one-way valve provided in the second supply passage. A Reynolds number of a flow in the first one-way valve is equal to or smaller than 2300 when a flow rate per unit time of the flow in the first one-way valve is maximum. A Reynolds number of a flow in the second one-way valve is equal to or smaller than 2300 when a flow rate per unit time of the flow in the second one-way valve is maximum.

Abstract: A steering system, comprising: an input cylinder having a first hydraulic chamber and a second hydraulic chamber; a transmission mechanism, wherein a transmission efficiency for converting and transmitting a linear motion of the input cylinder to a rotary motion of a steering wheel is less than a transmission efficiency for converting and transmitting the rotary motion of the steering wheel to the linear motion of the input cylinder; an output cylinder connected to a steerable vehicle wheel and having a third hydraulic chamber and a fourth hydraulic chamber; a first hydraulic passage for connecting the first hydraulic chamber to the third hydraulic chamber; a second hydraulic passage for connecting the second hydraulic chamber to the fourth hydraulic chamber; a flow rate control mechanism for exchanging hydraulic oil with: a first hydraulic circuit including the first and third hydraulic chambers and the first hydraulic passage; and a second hydraulic circuit including the second and fourth hydraulic chambers

Abstract: A method of steering a vehicle with a hydraulic steering system is disclosed. A first control signal is sent to a pilot valve. The pilot valve is operated to direct pilot fluid to a main valve in response to the first control signal. The main valve is opened to a first position in response to the pilot fluid. Fluid is directed through the main valve to a first actuator. Resistance to actuation of the first actuator is detected. The detected resistance is compared to a threshold resistance. A second control signal is sent to the pilot valve when the detected resistance exceeds the threshold resistance. The pilot valve is operated to direct pilot fluid to the main valve in response to the second control signal. The main valve is opened to a second position in response to the pilot fluid. Fluid is directed through the main valve to the first actuator and a second actuator.

Abstract: An engine driven pump 24 is connected with a power steering motor assembly 18. An electric motor 36 drives a pump 34 connected with the power steering motor assembly 18. A controller 38 effects operation of the electric motor 36 to drive the pump 34 to supply fluid to the power steering motor assembly 18 at a flow rate based on the speed of the engine 28.

Abstract: A front steering module adapted for integration with the subframe of a zero-turn radius vehicle incorporating an electronic steering apparatus. The module provides both front wheel steering and corresponding control inputs for the electronic steering apparatus. The module has a frame member having a pair of steered wheel assemblies mounted thereto and a mounting member for attachment to the vehicle. The module further comprises a steering mechanism and a steering position sensor for providing input to the electronic steering apparatus.

Abstract: A power steering system includes a double-acting power cylinder (16) having a four-way valve (20) for controlling steering direction. An accumulator (26) stores pressurized fluid that is controllably supplied to the four-way valve (20) by an electronically controlled three-way valve (28) based upon an applied torque measured at a steering wheel (12).

Abstract: An automotive steering rack stroke adjusting device is disclosed that detects a change in a gap defined between steerable wheels and a vehicle body depending on a change in the stroke of the steerable wheels using a vehicle height sensor, and automatically adjusts the rotation of a plurality of rotary bodies with respect to a stop plate of a steering rack, so that the optimized maximum stroke of the steering rack can be set according to the driving conditions of the vehicle. Furthermore, the present invention is able to increase an adjustment range of the stroke of the steering rack, so that a minimum rotation radius of the vehicle may be reduced, thus markedly enhancing the driving convenience.

Abstract: A power steering system for a vehicle includes a hydraulic system for controlling resistance of a steering wheel. A valve of the hydraulic system is connected to a coil which varies positioning of the valve. A method for controlling the resistance of the steering wheel includes turning the steerable wheels of the vehicle in response to rotation of the steering wheel. The angle of the steering wheel and the speed of the vehicle are sensed and inputted into a controller. A lateral acceleration is determined based on the sensed signals by the controller. A recommended current rate of the coil is determined based on the lateral acceleration. An adjustment to the recommended current rate of the coil is determined based upon the speed of the vehicle. The recommended current rate is also modified based upon the adjustment. The modified current rate of the coil is then applied to the coil to vary the stiffness of the valve, which in turn varies the resistance to turning the steerable wheels of the vehicle.

Abstract: A hydraulic steering system for a work machine may include a first steering actuator having a first and a second chamber. In addition, the steering system may include a second steering actuator having a third and a fourth chamber. A multi-position directional valve may include at least one low power position and at least one high power position. The low power position may be configured to direct fluid only to the first chamber during a low power turn to extend the first steering actuator. The high power position may be configured to direct fluid to the first chamber and the third chamber during a high power turn to retract the second steering actuator.

Abstract: A power steering system includes first and second communication passages for providing communication between a first oil passage and a second oil passage, a third communication passage for providing communication between the first and second communication passages, a directional control valve disposed in the third communication passage, a first check valve disposed in the first communication passage for allowing flow from the first oil passage to a first connection portion only, a second check valve disposed in the first communication passage for allowing flow from second oil passage to the first connection portion only, a third check valve disposed in the second communication passage for allowing flow from a second connection portion to the first oil passage only, and a fourth check valve disposed in the second communication passage for allowing flow from the second connection portion to the second oil passage only.

Abstract: The present invention provides a power assist steering system for use with a motor vehicle utilizing a torque sensor and an electronically controlled hydraulic valve used to supply or meter hydraulic fluid to a hydraulic cylinder that provides power assist to the steering system. The torque sensor measures driver input and provides a signal to the controller that controls an electrically actuated hydraulic valve. Additionally, steering wheel rotational speed and position are also input to the controller wherein the controller generates a steering assist command that minimizes the magnitude of difference, or error, between the steering torque reference value determined from the steering wheel speed and position and the measured torque. By doing so, the invention controls steering wheel feel, as opposed to the conventional practice of controlling the steering assist boost curve.

Abstract: The invention provides a steering system e.g. for a vehicle. The system comprises a system-pump, a steering actuator, a rotary valve, a rotary meter, and a motor. The system-pump is arranged to provide a flow of a fluid to the steering actuator via the rotary valve and via the rotary meter, and the motor is arranged to provide rotation of the rotary valve and the rotary meter. To handle an emergency situation if the system-pump fails, the motor is dimensioned to operate the rotary meter as a fail-operational pump for pumping a flow of the fluid to the steering actuator if the system-pump fails.

Abstract: A drive train for a compressor and a hydraulic pump of a motor vehicle, and a method of use are described. The system includes a hydraulic power steering system, an electric superimposed steering system for providing steering assistance, and a motor vehicle drive motor with a common output shaft for driving the compressor and the hydraulic pump. Also provided are means for reducing the power which is supplied to the compressor and to the hydraulic pump via the output shaft, when demands made of the compressor and of the steering assistance system permit reduced power operation. The power which is supplied to the compressor and to the hydraulic pump via the output shaft may be reduced substantially to zero when operation of the compressor is unnecessary and the electric superimposed steering system is sufficient to provide alone the steering assistance.

Abstract: Method and device for controlling a vehicle's operation by sensing a vehicle driver's operation of a control element of the vehicle, and the steering angle of the vehicle being regulated depending on the operation of the control element. The speed of the vehicle is sensed, a procedure for changing the steering angle of the vehicle is defined based on the sensed operation of the control element and the sensed vehicle speed, and the steering angle of the vehicle is regulated according to the defined procedure.

Abstract: The invention generally relates to an improvement of conventional Hydraulically Power Assisted Steering system (HPAS-system) arranged to supply a steering assist force to the steering assembly of a vehicle as a response to a torque applied by a driver to the steering wheel. In such HPAS-systems a certain drivers torque always results in a certain assist force. The invention therefore discloses a valve that can be actuated to dynamically alter the steering assist force produced by the HPAS-system. This makes it possible to dynamically adjust the assist force so that an appropriate force may be delivered to fit the specific driving scenario.

Abstract: The invention relates to a hydraulic steering system (1) comprising a hydraulic steering unit (2) and an auxiliary device (3). Said steering unit (2) feeds a hydraulic medium to a steering cylinder (5) according to the movement of a steering wheel (4). The auxiliary device (3) comprises a valve unit (6) and also feeds a hydraulic medium to the steering cylinder (5) according to the movement of the steering wheel (4), in order to assist the steering movement. The hydraulic medium ejected or discharged from the steering cylinder (5) as a result of the hydraulic medium fed thereinto flows back into a tank (10) or to a pump (8, 9) by means of the steering unit (2).

Abstract: A power steering apparatus includes a hydraulic power cylinder, a reversible pump including a first outlet connected with a first pressure chamber of the power cylinder through a first fluid passage, and a second outlet connected with a second pressure chamber of the power cylinder through a second fluid passage, and a motor for driving the pump. A controller controls the motor in accordance with a sensed steering force. There is further provided a connection passage connecting the first and second fluid passages together, and a closing valve disposed in the connection passage. The controller sends a first current to a coil of the valve to close the connection passage by moving an armature, to send a second current lower than the first current to the coil after the connection passage is closed, and to deenergize the coil to open the connection passage.

Abstract: A steering apparatus for a vehicle includes a steering angle measuring unit, a vehicle speed measuring unit, a yaw rate measuring unit, a yaw rate-based reaction force control unit for controlling a steering reaction force depending on an actual yaw rate measured by the yaw rate measuring unit, and a yaw rate deviation-based reaction force control unit for determining a standard yaw rate depending on at least the steering angle and the vehicle speed, calculating a yaw rate deviation between the standard yaw rate and the actual yaw rate, and controlling the steering reaction force depending on the yaw rate deviation, and a primary control unit for executing a control operation such that a degree of contribution of the yaw rate-based reaction force control unit is decreased and a degree of contribution of the yaw rate deviation-based reaction force control unit is increased as the yaw rate deviation increases.

Abstract: An apparatus (10) for use in turning steerable vehicle wheels (14, 16) includes a hydraulic power steering motor (12). A pump (26) is operable to supply hydraulic fluid to the power steering motor (12). A gearset (50) is connected with the engine of the vehicle and the pump (26). The gearset (50) is operable to drive the pump at a first speed during turning of the steerable vehicle wheels (14, 16) at relatively low vehicle speeds. The gearset (50) is operable drive the pump at a second speed during turning of the steerable vehicle wheels at relatively high vehicle speeds. The second speed which is less than the first speed. The gearset is a differential gear mechanism.

Abstract: A power assist steering system including a valve housing and a proportional control valve supported within the valve housing, further includes a pressure transducer arranged with respect to the proportional control valve for determining an amount of actuation of the proportional control valve. A pressure signal is sent from the pressure transducer to a control for determining an amount of current to be sent to an electromagnetic apparatus within the power assist steering system for overcoming a pull force.

Abstract: A controller controls right and left wheel drive motors based on a tire angle detected by a tire angle sensor such that the angular velocities of a pair of drive wheels about the center of a turn of the vehicle are equal to each other. The controller determines a steering speed of a steered wheel at the time a steering wheel is turned, from the tire angle detected by the tire angle sensor. Based on the steering speed, the controller controls a hydraulic pressure control motor, enabling a hydraulic pump to supply working fluid at a rate corresponding to the steering speed through a priority valve to a steering cylinder. With this arrangement, the vehicle is allowed to make a smooth turn.

Abstract: A power steering pump comprises a housing that includes a bore, a fluid discharge port that supplies pumped fluid into the bore, and a fluid bypass port for recycling excess fluid to the pumping elements. The pump outlet is at one end of the bore. A flow control valve is slideably received in the bore and regulate the size of the inlet to the fluid bypass port. The pump includes a solenoid assembly that has a plunger that is operatively connected to the flow control valve through the second end of the bore opposite the pump outlet. By adjusting the magnitude of the current to the electromagnetic coil of the solenoid assembly, the position of the flow control valve is varied to increase or decrease fluid flow to the fluid bypass port and thereby regulate the output from the pump.

Abstract: A hydraulic power steering system with a steering gear and a hydraulic actuator for supporting a steering wheel actuation by the driver of a vehicle, in particular a motor vehicle, includes components for actively applying an additional steering torque, the components for actively applying an additional steering torque including at least one additional torque actuator and a steering torque detector being mounted as a module on a steering wheel shaft that connects the steering wheel to the steering gear.

Abstract: A first fluid passage extends from a first outlet/inlet port of a hydraulic pump to a first work chamber of a power cylinder, and a second fluid passage extends from a second outlet/inlet port of the pump to a second work chamber of the power cylinder. A switch system switches the role of the first and second outlet/inlet ports in accordance with a turning direction of a steering wheel. Flow control mechanisms are respectively incorporated with the first and second fluid passages, so that a controlled flow of hydraulic fluid from the hydraulic pump to the first or second work chamber and vice versa are appropriately carried out thereby providing the driver with a comfortable steering feeling. A bypass arrangement may be provided between the first and second fluid passages to deal with a residual pressure that would be remained in the first or second work chamber when the hydraulic pump is under inoperative condition.

Abstract: This invention provides a vehicle motion control method and a vehicle motion control apparatus capable of improving the behavior stability of a vehicle. According to the vehicle motion control method, vehicle steering characteristic is determined based on a behavior amount differentiated value obtained by differentiating (S203) a slip angle differential value which is a behavior amount of the vehicle which occurs around a z-axis in the vertical direction with respect to the vehicle body (S205, S209). Consequently, because the phase of the slip angle differential value is progressed, the transition tendency of the steering characteristic, that is, which the vehicle motion condition is moved to over-steer or under-steer, can be obtained early. Therefore, the starting timing of the steering control or drive power control of the vehicle can be accelerated thereby improving the behavior stability of the vehicle.

Abstract: The invention relates to a hydraulic power-assisted steering system comprising a steering gear and a hydraulic actuator for assisting actuation of the steering wheel by the driver of a vehicle, in particular a motor vehicle, comprising an electric motor which is coupled to the steering column and used as an additional torque actuator for actively applying an additional steering torque, also consisting of an electronic control and regulating unit (ECU), which includes a determination unit for determining a steering torque and an evaluating and selecting circuit, by means of which a total value for applying the additional steering torque is determined in consideration of the determined steering torque or a quantity derived therefrom and a selected basic characteristic curve of steering (basic characteristic curve), with the total value of the additional steering torque to be applied including a driver-dependent component and a driver-independent component.

Abstract: An electro-hydraulic power steering system for a vehicle includes a booster pump rotated by an electric motor, under control of a computer, as a function of a signal representing speed of the vehicle and a signal representing rate of steering wheel angle change. The computer generates the signal representing the rate of steering wheel angle change by computation from current supplied to the motor to control the booster pump.

Abstract: An assembly consists of a valve shaft, a valve member and an adjusting device which can alter the angle alignment of the valve member relative to the valve shaft.

Abstract: A variable gear ratio hydraulic power steering device 1 is provided with a variable ratio transmission mechanism 7 having a drive motor 70; a flow volume control valve 41 for controlling the discharge flow volume of an oil pump 10 which circulates operating fluid; and a steering angle sensor 310 for measuring a handle steering angle input to a steering handle 31. A valve controlling controller 50 is constructed to take thereinto a measured ACT angle which is the rotational angle of the drive motor 70 and to calculate a target ACT angle for the drive motor 70 based on the handle steering angle. Further, the valve controlling controller 50 controls the flow volume control valve 41 to make the discharge flow volume equal to or greater than a predetermined flow volume when the magnitude of a difference ACT angle which is the difference between the target ACT angle and the measured ACT angle is equal to or greater than a threshold value.

Abstract: The present invention provides a device for dynamically counteracting torque steer which includes a processor adapted to calculate a correction factor from a calculated axle torque on front wheel drive half shafts of the vehicle. A power circuit is provided responsive to the calculated correction factor to provide an offset current through the power steering unit or the braking system of the vehicle to counteract the torque steer.

Abstract: In a power steering system, the steering state of wheels is detected based on the steering speed to judge as to whether the steering state is in turning of the steering wheel or holding of steering speed is the steering wheels. At the time of the steering operation state, the control is executed so that a difference between a torque command value to an electric motor and the actual torque thereof will become smaller. Also, at the time of the holding operation state, the control is executed so that a difference between the revolution speed of the electric motor and a revolution-speed command value thereto will become smaller.