| 摘要 |
PURPOSE:To make the mechanism of a running speedometer used for automobiles or the like simple by controlling a pulse motor in such a way that the pulse motor is run forward, is run backward or is stopped by the difference between the current count value of a pulse generator and the count value just before the same. CONSTITUTION:The frequencies corresponding to vehicle speeds generated from a pulse generator 1 are shaped to square waves by a control circuit 2, after which they are successively counted at every preset time interval, and the pulse motor driving pulses of the number equal to the difference between the current count value and the count value just before the same and the forward and backward run signals for a pulse motor are generated. The driving pulses and the forward and backward run signals obrained in this way are successively distributed to plural poles of coils of a pulse motor 4 by a pulse motor driving circuit 3, whereby the pulse motor 4 is run forward or backward or is stopped. Since such controlling is carried out, there is no need for any position detector for the control circuits, and the mechanism is made simple. |
