Honda Giken Kogyo Kabushiki Kaisha

Makoto Murata

Osamu Tsurumiya

Masataka Izawa

Yoshikazu Tsuchiya

Yukihiro Fujiwara

Masaru Abe

Nobuo Sugitani

Atsushi Kurauchi

Masaaki Kawano

Takao Kurosawa

Kouji Sasajima

Tomoaki Sugano

The object of the present invention is to provide a driving apparatus for a vehicle, which is capable of improving the operability and safety of a vehicle driving by enabling a fine correction to the steering amount with a simple apparatus. The apparatus employs the first and second operation devices, for which the steering gains are differentiated for the improvement.

Driving apparatus for a vehicle

An electric power steering apparatus comprises an electric motor a vehicle speed detecting section (vehicle speed sensor) VS, a shifting state detecting section for detecting a shifting state of the vehicle, an engine rotational speed detecting section (engine rotational speed sensor) ES, and a motor control section (controller) for controlling drive of the electric motor The motor control section includes a failure determination section (vehicle speed sensor failure determination section) for determining failure of the vehicle speed detecting section on the basis of a vehicle speed, a shifting state and an engine rotational speed. The failure determination section determines that the vehicle speed detecting section VS malfunctions if the engine rotational speed is equal to or greater than a predetermined rotational speed for a determinative continuous-time and/or a first determinative integrated time while the vehicle speed is zero and the shifting state is a vehicle driving state.

Electric power steering apparatus

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.

Vehicle including a variable gear ratio steering device and an electric power steering apparatus

An electric motor control system has a motor driver comprising a bridge of switching elements, a pair of failure detectors, and a microcomputer. The motor driver is connected between a battery and an electric motor that is connected between the switching elements. The switching elements are turned on and off according to drive pulse signals supplied from the microcomputer for supplying a pulsed current to the electric motor. The failure detectors monitor the electric energy supplied to the electric motor to detect a period of time in which the supplied electric energy is free of pulses, and supply a signal indicative of the detected period of time to the microcomputer. Based on the signal from the failure detectors, the microcomputer detects a failure when the detected period of time exceeds a predetermined period of time.

Electric motor control system

A four-wheel steering system on an automobile has front road wheels steerable by a steering wheel and rear road wheels steerable by an electric motor and normally biased to a neutral steering position by a spring. The electric motor is energized by a motor driver to steer the rear road wheels through an angle depending on running conditions of the automobile. The electric motor has a winding and two sets of brushes or connecting terminals connected to opposite terminals of the winding. One of the two sets of connecting terminals is connected to the motor driver. The other of the two sets of connecting terminals is connected to a short-circuiting circuit parallel to the motor driver. In the event of a failure, a controller controls the short-circuiting circuit to short-circuit the winding of the motor through the other set of connecting terminals. The short-circuiting circuit comprises a plurality of relays having respective contacts connected in series between the connecting terminals of the other set. The motor driver can also short-circuit the winding of the motor through the one set of connecting terminals in the event of a failure.

Four-wheel steering system with steering motor short circuit control

A front and rear wheel steering system for a motor vehicle with steerable front and rear road wheels includes a front wheel steering mechanism for steering the front road wheels in response to a steering action effected by a steering wheel of the motor vehicle, a neutral positioning mechanism for normally urging the rear road wheels under a resilient force to a steering neutral position, a rear wheel steering mechanism having an electric motor for steering the rear road wheels out of the steering neutral position, and a controller for controlling an electric current supplied to the electric motor depending on the steering action of the steering wheel. The controller reduces the electric current supplied to the electric motor and subsequently holds the reduced electric current while the motor vehicle is at rest and no steering action is effected by the steering wheel. Preferably, the controller controls the electric current supplied to the electric motor to reach a value which enables the electric motor to produce an output force smaller than the resilient force produced by the neutral positioning mechanism.

Growing community of inventors

Wako, Japan

Makoto Murata