Abstract: A flow regulating valve having an opening valve, which opens or closes a first passage 5m, 25, 5k, 5j and 5h and this opening valve is provided with a second passage 8 and includes a housing 5a accommodating an orifice 9 and a cylindrical member 24 concentrically engaged on this housing 5a. By relative movement of the housing 5a and the cylindrical member 24, the first passage is opened or closed. Further, in normal case, the flow regulating valve 6 opens the opening valve and communicates the master cylinder 1 with the passage selector valve 5 through the first passage. When the pressure difference on both ends of the cylindrical member 24 exceeds the preset value, the cylindrical member 24 is slid and the opening valve closes the first passage, and the discharge side of the pump 12 is communicated with the passage selector valve 5 only through the second passage 8.

Abstract: An electric power steering apparatus includes a torsion bar, input and output shafts, an electric motor, and a detecting mechanism. The input and output shafts are coupled to each other by the torsion bar so as to be pivotally displaced in relation to each other. The electric motor is coupled to the output shaft so as to apply an auxiliary steering force. The detecting mechanism detects a relative, pivotal displacement of the input and output shafts. Main portions of the input and output shafts are coaxially arranged. One of the shafts is a cylindrical member having an outer end in which the torsion bar is housed. An inner end of one shaft is pivotally inserted in an opening of a cylindrical inner end of the other shaft. The detecting mechanism is arranged on the outer surface of an outer shaft of the input and output shafts at their overlap portion.

Abstract: A four-wheel steering system includes a torque sensor, a first steering angle sensor, a vehicle speed sensor, a second steering angle sensor, a first DC motor, a second DC motor, and a controller. The torque sensor outputs a front-wheel steering force signal. The first steering angle sensor outputs a front-wheel steering angle signal. The vehicle speed sensor outputs a vehicle speed signal. The second steering angle sensor outputs a rear-wheel steering angle signal. The first DC motor supplies a torque to a front-wheel steering system. The second DC motor supplies a torque to a rear-wheel steering system. The controller outputs a rear-wheel steering force signal by detecting a current supplied to the second DC motor, and determines a control target value by receiving the front- and rear-wheel steering force signals and the front- and rear-wheel angle signals, and the vehicle speed signal.

Abstract: Inlet passages and two sets of discharge passages are communicated with a pair of pump chambrs formed in a pump cartridge in a pump body. A pair of spool valves respectively acting as a flow quantity control valve and a pressure sensitive type flow path switchng valve are formed in parallel in the pump body in directions perpendicular to the axis of the pump.

Abstract: An electric power steering apparatus causes a bridge circuit and a driver circuit to control normal and reverse rotation operations of a motor. The bridge circuit is constituted by transistors. The driver circuit is connected to a power source and also is connected to the bridge circuit so as to drive the bridge circuit. A diode is inserted between the power source and the bridge circuit, and the polarities of the diode are set such that a voltage at the bridge circuit is lower than that at the driver circuit.

Abstract: An electric power steering apparatus comprises a steering shaft including a torsion bar to join an input shaft on the side of a steering wheel and an output shaft on the side of a steering road wheel so that they can be rotationally displaced relative to each other, and a non-contact type sensor using a Hall effect device provided in association with the input and output shafts to sense a relative rotational displacement based on a torsion of the torsion bar. The electric power steering apparatus further comprises an electric motor provided around a steering gear body within which the steering shaft is disposed and is driven by a signal from the non-contact type sensor to render a steering assistance to an output shafting leading to the steering road wheel.

Abstract: An electrical power steering apparatus includes a vehicle velocity sensor for detecting a vehicle velocity, a steering torque sensor for detecting a steering torque of a steering wheel, comparators for receiving the voltage signal from the steering torque sensor and detecting a steering direction, a motor drive mechanism, a vehicle wheel declination sensor for detecting a declination of a vehicle wheel, a nonsteering state detecting unit including an absolute value converter, a reference voltage generator and a comparator to detect a nonsteering state, and a controller for supplying a current of a magnitude corresponding to the declination of the vehicle wheel to the motor so as to decrease the declination during the nonsteering state.

Abstract: A steering apparatus for a vehicle steers both front and rear wheels and has an electric power steering unit for steering the rear wheels with a rotational force of a motor and a controller for generating a rear wheel steering signal in response to a vehicle speed and a front wheel steering angle. The controller includes a plurality of pattern memories for storing rear wheel steering angles, one of which is read out in response to a detected front wheel steering angle in accordance with ratios of rear wheel steering angles to front wheel steering angles. The ratios are predetermined or given as a function of vehicle speeds.

Abstract: A power steering device including a vane type oil pump having vanes which are radially movable in slits of a rotor to supply hydraulic fluid from an oil reservoir tank to a power cylinder through a flow passage switching valve. Chambers are defined behind the valves at base ends of the slits. Hydraulic fluid having a pressure built up by the reciprocal motion of the valves in the chambers is supplied through a solenoid coil type flow control valve to hydraulic reaction force chambers of a power cylinder control valve to thereby control a force applied between input and output shafts thereof, thereby to determine the steering force required.

Abstract: Power steering control apparatus utilizing on oil pump comprises a car speed sensor producing a car speed signal, a steering sensor producing a steering signal, a mean car speed calculating circuit, a mean steering quantity calculating circuit, a mean lateral acceleration calculating circuit calculating a mean lateral acceleration based on the mean car speed and the mean steering quantity, a car speed calculating circuit, pattern memory means storing a plurality of number of revolutions characteristics of the oil pump corresponding to different patterns, a selector selecting one of the number of revolutions characteristics in accordance with the mean lateral acceleration and the mean car speed, circuit means for deriving out a number of revolutions signal of the oil pump corresponding to the car speed, and control means controlling rotation of the oil pump in accordance with the derived out number of revolutions signal of the oil pump.

Abstract: A vehicle power steering apparatus for rotating a motor in response to a torque signal generated in response to a rotational torque of input and output steering shafts and for driving a steering direction control unit using a rotational force of said motor so as to perform power steering, comprising: vehicle velocity detecting means for detecting a vehicle velocity; rotational direction and rotational torque detecting means for detecting a rotational direction and a rotational torque of the input and output steering shafts in response to a signal generated by the rotational torque of the input and output steering shafts; controlling means for controlling the rotational direction of the motor in response to a detected rotational direction; and torque controlling means for decreasing the rotational torque of the motor in response to a detected vehicle speed signal when the vehicle speed is increased, and for increasing the rotational torque of the motor in response to the detected vehicle speed signal when a st

Abstract: A vehicle power steering apparatus for performing power steering by rotating a motor in accordance with a steering torque acting on input and output steering shafts and driving a steering direction control unit to perform power steering, comprises a sensor for generating an electrical signal corresponding to a displacement of a movable member displaced by a rotational force acting on the steering wheel; a controller for rotating the motor at a torque represented by the electrical signal during an ON time of the electrical signal generated from the sensor; and moving means for moving the movable member in a direction to cancel the displacement of the movable member driven by the motor.

Abstract: In a power steering apparatus for use in a motor car of the type including a control device for controlling a motor driven oil pump in accordance with the output of a sensors which detects the running condition of the motor car driven by an engine, there is provided a control system which stops the oil pump while the engine is being stopped and also stops the oil pump at the time of starting the engine.

Abstract: A power steering apparatus wherein an oil pump for actuating the power steering apparatus is controlled by a control device in accordance with an output of a sensor device detecting the running state of a motor car. The control device drives said pump when said sensor device detects that the car speed is lower than a predetermined value but stops said pump when said sensor device detects that said car is standstill while the steering wheel of the motor car is not operated.

Abstract: In an oil pump having two pump cartridges each acting as independent pumps, a pair of suction passages and a pair of discharge passages opened in a pair of pump chambers in the pump cartridges are formed in one pump body secured to one side of the cartridges, a flow control valve is contained in an opening extending in an axial direction of the pump body, and a pressure sensitive flow passage change over valve is contained in another valve opening perpendicular to the valve opening. The two valve openings are communicated with the discharge and suction openings.

Abstract: A flow path switching valve is provided, operating to merge hydraulic fluid from a plurality of pumps in accordance with a magnitude of a loading applied to a hydraulic unit, and a variable orifice is defined adjacent to the valve. A flow control valve is also provided for returning part of the hydraulic fluid to a tank, and operates in accordance with the throttle opening of the variable orifice which changes in accordance with the operation of the flow path switching valve.

Abstract: In an oil pump of the type comprising a cartridge having an elliptical cam ring in which a rotor having a plurality of vanes is rotated to form a pair of pump chambers symmetric with respect to an axis of rotor, and a pair of suction passages and two pairs of discharge passages are provided for the pair of pump chambers. A valve opening is formed coaxially with the rotor in a pump body secured to one side of the cartridge to contain the spool valve. A metering orifice is provided in a discharge passage to actuate the spool valve in response to a pressure differential such that when the pump speed is low all outputs of both pump chambers are supplied to a load, whereas when the pump speed is high a portion of the outputs is supplied the suction side. According to this construction it is possible to decrease power consumption and to decrease the size and weight of the oil pump.

Abstract: A flow-control valve exhibits a flow-drooping characteristic such that the liquid supply into an oil pressure mechanism is decreased in response to an increase of the amount of liquid discharge from a pump. The pump outlet passage forms branches into a fluid supply passage communicating with an oil pressure mechanism and a recirculating passage back to an oil tank. A control valve located in the recirculating passage is opened in response to the fluid increase from the pump to recirculate a part of the fluid into the tank. An orifice not receiving large influences of the pressure variation is disposed either at the pump outlet passage or the recirculating passage and a variable orifice valve is disposed in the fluid supply passage. The variable orifice is controlled by the pressure differential existing between the upstream and downstream portions of the orifice at either location.

Abstract: A pump of vane type which sucks in and discharges fluid includes a pump body which is provided with at least two sets of intake ports and discharge ports, which communicate with a low pressure chamber and a high pressure chamber, respectively. An intake port and a discharge port of each set is spaced apart in substantial coincidence with a spacing between a pair of adjacent vanes, and an intake port (or a discharge port) of a second set is located between an intake port and a discharge port of a first set. Means is provided which controls the communication between selected intake ports and the low pressure chamber and between selected discharge ports and the high pressure chamber.

Abstract: A plurality of pump sections are received in a stack in a body. Each of the pump sections include a cam ring disposed in surrounding relationship with a rotor having vanes thereon, and a pair of sideplates which closes the opposite sides of the cam ring. All of the pump sections are driven by a common drive shaft, thereby providing a compact pump unit having a reduced axial length. The outermost sideplates are subject to a discharge pressure from the respective pump sections to urge the various components of the individual pump sections to be held against the body. In this manner, the components are maintained at given accurate locations, eliminating the likelihood of a liquid leakage and simplifying the arrangement.