| 摘要 |
<p>PURPOSE:To obtain a stable characteristic of return steering with no hand in a steering system, by providing an electric motor braking means which applies a brake to an electric motor when the steering system provides its steering torque to be in a predetermined value or less further with a rotary speed of the electric motor in a predetermined value or more. CONSTITUTION:A steering torque detecting means 41 detects steering torque in a steering system, while an electric motor rotary speed detecting means 42 detects a rotary speed of an electric motor 10. And on the basis of output signals from said both detecting means 41 and 42, if the steering torque is detected to be in a predetermined value or less further with the rotary speed of the electric motor 10 in a predetermined value or more, a zero torque overspeed detecting means 45, which detects the steering system to be placed in a condition of return steering with no hand, outputs a brake signal to an electric motor braking means 46. In this way, the electric motor 10 applies a self brake. Accordingly, the steering system in the time of return control with no hand is reset to the intermediate position within a short time, and a stable characteristic of return steering with no hand can be obtained.</p> |
