| 摘要 |
PURPOSE:To keep motor load constant regardless of the fluctuation of a driving voltage value by changing the setting of the length of the unit time on the basis of a result, in which a current variation is detected from the driving voltage value. CONSTITUTION:Voltage-dividing resistors 11, 12 are supplied with driving voltage Vb fed to a motor 1, a voltage measuring device in a microprocessor unit 8 is supplied with voltage at the node of the voltage-dividing resistors 11, 12 as the display of the fluctuation of driving voltage Vb, and voltage at the node is converted digitally and an internal voltage response-time setter is fed with the digitally converted voltage. When the length of the unit time DELTAt at a time when driving voltage Vb is a stationary value 12V is normal length DELTAt1, the length of the unit time DELTAt is made shorter than DELTAt1, successively in response to the fluctuation width of driving voltage Vb when driving voltage Vb is changed in the direction that driving voltage Vb is increased from the stationary value 12V, and made longer than DELTAt1, successively when driving voltage Vb is altered in the direction that driving voltage Vb is reduced from the stationary value 12V, thus preventing the dependence of a current variation DELTAi per the unit time DELTAt on driving voltage Vb, then detecting the current change of a fixed quantity in the motor 1 at all times. |
