| 摘要 |
PURPOSE:To prevent the operating feeling of steering from becoming poor by increasing the rate of electrification at the neutral position of steering when the voltage of a battery is lowered below reference voltage. CONSTITUTION:When a steering is operated, voltage flowing into a shaft 2 increases and the output of a current comparator 6 becomes a high level, raising electric potential. Then, the duty of an oscillating circuit VCO is increased, and the number of revolution of a motor PM is raised, driving a steering pump at a high speed. If a battery is excessively discharged, with its voltage being decreased, a voltage detecting circuit 5 detects this and raises an A-point voltage. Thereupon, the duty of the oscillating circuit VCO at the neutral position of steering is increased. Accordingly, the rotation of a motor can be rapidly started even when steering operation is carried out in a low voltage condition of the battery. |
