Jidosha Kiki Co., Ltd.

Hideo Yabe

Sadao Takeshima

Ichiro Koike

Yoshio Suzuki

Hirotetu Sonoda

Akimitsu Ebina

Hideo Hori

In a self-check method of a four-wheel steering drive system, a relay downstream current upon ON/OFF of a relay is checked to check a state of said relay. Forward and reverse rotation control signals of a duty ratio of 0% are supplied to a predetermined combination of switching elements constituting an H bridge circuit to check if a current obtained from the predetermined combination of switching elements is an overcurrent, thereby checking a state of the H bridge circuit. When the rear wheels are turned to a target rear wheel position with reference to a present rear-wheel position, whether or not a difference between the target rear-wheel position and an actual rear-wheel position is set to be a predetermined value or less within a predetermined period of time is checked, thereby checking a state of a steering motor and a rear-wheel steering mechanism.

Self-check method of four-wheel steering drive system

A control device for a power steering apparatus includes a vehicle speed signal generator, a steering angle signal generating circuit, a first pattern memory, a second pattern memory, and a drive circuit. The vehicle speed signal generating circuit generates a vehicle speed signal corresponding to an actual vehicle speed. The steering angle signal generator detects a steering angle and generates a steering angle signal. The first pattern memory generates a power steering signal determined in correspondence with the vehicle speed signal. The second pattern memory generates a correction signal determined in correspondence with the vehicle speed signal and the steering angle signal representing a steering angle with respect to a neutral position of a steering wheel. The drive circuit outputs a correction result by correcting the power steering signal by the correction signal.

Control device for power steering apparatus

The operating condition of a power steering device for use in a motor car of the type including a steering mechanism driven by a electric actuator is confirmed by supplying test current to the electric actuator before starting the motor car and then detecting the state variation of the power steering device caused by the test current. The electric actuator may comprise a combination of an electric motor and an oil pump driven thereby, or an electric motor directly coupled to a steering mechanism.

Method and apparatus for power steering

A load current control device operates so as to control the magnitude of a current delivered to a load by varying a duty factor. With this control device, a fundamental value is determined on the basis of an instruction of an input signal, and a reference duty factor and a reference current value are determined on the basis of the fundamental value. The control device further operates to correct the reference duty factor on the basis of a difference between the magnitude of a current actually flowing in the load and the reference current value to turn on and off a power supplied in accordance with the corrected duty factor, therby to control the magnitude of the load current. In addition, when the above-said difference is out of a predetermined range, this load current control device outputs a signal indicative of abnormal condition.

Load current control device

A transmission remote control apparatus with a plurality of gear shift positions so as to shift a gear shift lever between gears through corresponding neutral positions has a diagnosis unit which has: a drive circuit for sequentially moving the gear shift lever in all neutral positions; a detector for detecting that the gear shift lever has passed all the neutral positions; an alarm generator for generating an alarm when a failure is detected; and a controller for controlling the drive circuit, the detector and the alarm generator.

Transmission remote control apparatus

In a control device for a power steering apparatus of which steering force is controlled on the basis of a control signal produced in accordance with a vehicle speed signal, the control device comprises means which outputs an engine rotation speed signal corresponding to an engine rotation speed, change relaxation means for relaxing changes in the engine rotation speed signal, and a switchover circuit which outputs an output signal of the change relaxation means instead of the vehicle speed signal when the vehicle speed signal is lost. Accordingly, even if a vehicle speed sensor is out of order for any reason, the power steering is carried out by the engine rotation speed signal, resulting small change of the steering force. Thus, this can protect the vehicle driver from dangerous conditions.

A hydraulic reaction force apparatus for a power steering system has a pump, a power cylinder, a control valve, a first variable orifice, a hydraulic reaction force chamber, and a spool valve. The spool valve has a supply port connected to the pump, a reaction port connected to the hydraulic reaction force chamber, a tank port connected to a tank and a second variable orifice controlled by a spool in the spool valve. The opening of the second variable orifice is changed by a displacement of the spool caused by the pressure difference between upstream and downstream pressures of the first variable orifice, thereby connecting the reaction port to the supply port and the tank port and controlling the magnitude of the hydraulic reaction force.

Hydraulic reaction force apparatus for power steering system

A control apparatus for a power steering system has a travel condition data memory, a plurality of vehicle velocity response data memories, a correction data memory, and a driver. Traveling condition data is read out in response to average vehicle velocity data and average steering angle data. Vehicle velocity response data is read out from one of the vehicle velocity response data memories in response to the traveling condition data and instantaneous vehicle velocity data. The vehicle velocity response data is added by the driver to the correction data from the correction data memory. The corrected vehicle velocity response data is used to drive a control valve, thereby obtaining an optimal steering force.

Control apparatus for power steering system

Power steering control apparatus utilizing an 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 car speed calculating circuit, pattern memory means storing a plurality of number of revolution characteristics of the oil pump corresponding to different patterns, a selector selecting one of the number of revolution characteristics in accordance with the mean steering quantity and the mean car speed, circuit means for deriving out a number of revolution 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 revolution signal of the oil pump.

Method and apparatus for controlling power steering

A method and device for controlling a power steering apparatus for performing power steering by controlling a rotational speed of a motor-driven oil pump, wherein an alarm signal is generated when the power steering apparatus is overloaded, and a current is not supplied to a motor for a predetermined period of time when the power steering apparatus is overloaded.

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Saitama, Japan

Hideo Yabe