METHOD FOR CONTROLLING STEPPING MOTOR AND FLOW RATE CONTROLLER FOR VEHICULAR MULTI-DIRECTIONAL VALVE USING IT

摘要

PROBLEM TO BE SOLVED: To provide a method for controlling a stepping motor by which the malfunctions of the stepping motor and the degradation of durability caused by heat generation can be prevented without causing the enlargement of the size of a device and the increase of costs even if a power supply voltage is largely changed, and a flow rate controller for a vehicular multi-directional valve using it. SOLUTION: A control microcomputer 7 is provided with a variable rotational speed control circuit 16 which maintains the rotational torque of the stepping motor 6 at a fixed level by variably controlling the rotational speed of the stepping motor 6, by changing the pulse width of a motor control pulse impressed to the stepping motor 6 from the control microcomputer 7 corresponding to the changes (8-16V(DC)) of a driving power supply voltage detected with a power supply voltage detecting circuit 15. COPYRIGHT: (C)2005,JPO&NCIPI