| 摘要 |
PURPOSE:To prevent the generation of a continuous locking state when a power source voltage rises by applying the logic sum of the output of a rectangular wave oscillator and the output of a comparator to a control input terminal for a motor driver. CONSTITUTION:An operational amplifier 7 produces a differential voltage between a set voltage Via and the detection voltage Vib of a motor potentiometer 2 with the reference voltage Vc of a reference voltage generator 6 as a reference. The output voltage Vo of the amplifier 7 is compared by comparators 4, 5 with reference voltages Va, Vb, while the compared results are applied to a driver 3 to operate a motor 1 to obtain the state Va>Vo>Vb. An output of predetermined frequency is applied from an oscillator 10 through diodes 11, 12 to the driver 3. As a result, the motor 1 is driven while it is sometimes braked to prevent it from becoming a continuously locking state even if a power source voltage is raised. |
