| 摘要 |
PROBLEM TO BE SOLVED: To reduce the size and cost of a device for detecting displacement of a driven body by simplifying the configuration of, for example, the flow control valve for cooling water which is driven by means of a brushless motor. SOLUTION: A flow control valve, which controls the quantity of cooling water supplied to a radiator side, is constituted in such a way that the opening of the valve is controlled by means of a brushless motor 11. A phase sequence for detecting circuits 22a controls an up-down counter 22b upon receiving a switch signal for rectification which drives the motor 11. The opening of the flow control valve can be comprehended by computing the count value of the counter 22b by means of an arithmetic circuit 22c, and an ideal cooling controller for engine can be realized by feeding back the opening to a control unit 23 and computing the opening together with the other operational parameters. Since the need for an opening a sensor, etc., can be eliminated from the flow control valve, and particular, the size and cost of a device for detecting the displacement of the driven body can be reduced. |
