| 摘要 |
PURPOSE:To make self-reversing electrically possible and to materialize cost reduction of a DC motor, by providing electric normal and reverse rotating function and electric speed control function to the motor. CONSTITUTION:If a change-over switches 3a and 3b are set on A side, transistors 5 and 7 are in 'ON' state and a DC motor 9 rotates normally. If the switches 3a and 3b are set on B side, transistors 6 and 8 are in 'ON' state and the DC motor 9 rotates reversely. By comparing and controlling the counter electromotive voltage of the DC motor 9 and the reference voltage with a voltage comparator 15, the rotating speed is controlled. Thus, a unit can be obtained that controls the normal and reverse rotation and speed control of a small-sized DC motor electrically at the same time. |
