| 摘要 |
<p>A motor-assisted power steering apparatus includes a DC motor (2) which is fixed to a heat conductive frame (4), a torque sensor (19) for detecting torque of steering torque and a control circuit (3) for controlling current supplied to the motor (2). The control circuit (3) comprises a first unit disposed in a space defined by the frame (4) and the commutator (8) and a second unit disposed on an outside of the motor (2). The first unit includes a plurality of switching elements (18a-18d) connected to the motor (2) and a microcomputer (22) for setting motor current, a current detecting unit (24) for detecting current supplied to the motor (2), a current control unit (25) for providing duty ratio signals and a gate driving circuit (26) for driving the switching elements (18a-18d) according to the duty ratio signals. <IMAGE> <IMAGE></p> |
