초록 ▼

An electric power steering apparatus for a vehicle includes a fail-safe circuit for, on the basis of an engine running-state signal from an engine running-state sensor, enabling an electric motor to be driven by a motor drive unit so that a steering assist force from the electric motor is applied to

An electric power steering apparatus for a vehicle includes a fail-safe circuit for, on the basis of an engine running-state signal from an engine running-state sensor, enabling an electric motor to be driven by a motor drive unit so that a steering assist force from the electric motor is applied to the steering system of a vehicle. The fail-safe circuit, when the vehicle velocity detected by a vehicle velocity sensor is above a predetermined value, enables the electric motor to be driven by the motor drive unit even if the engine running-state sensor fails to detect the running state of the engine. Thus, even when a failure arises in the engine running-state sensor during movement of the vehicle, the motor can continue application of the steering assist force to the steering system. The electric power steering apparatus can always provide a good and stable steering feel as long as the vehicle is running even though the running state of the engine is not detected.

대표청구항 ▼

[ What is claimed is:] [1.]1. An electric power steering apparatus for a vehicle, comprising:a vehicle velocity sensor for detecting a velocity of the vehicle and generating a vehicle velocity signal corresponding to the detected vehicle velocity;an electric motor for applying a steering assist forc

[ What is claimed is:] [1.]1. An electric power steering apparatus for a vehicle, comprising:a vehicle velocity sensor for detecting a velocity of the vehicle and generating a vehicle velocity signal corresponding to the detected vehicle velocity;an electric motor for applying a steering assist force to a steering system of the vehicle;a control unit for generating a motor control signal on the basis of at least a steering torque applied to the steering system;a motor drive unit for driving said electric motor on the basis of said motor control signal;an engine running-state sensor for detecting a running state of an engine of a vehicle and generating an engine running-state signal corresponding to the detected running state of the engine; anda fail-safe circuit for, on the basis of the engine running-state signal from said engine running-state sensor being above a predetermined value, enabling said electric motor to be driven by said motor drive unit, whereinsaid fail-safe circuit, when a vehicle velocity detected by said vehicle velocity sensor is above a predetermined value, also enables said electric motor to be driven by said motor drive unit even if said engine running-state sensor fails to detect the running state of the engine.