| 摘要 |
PURPOSE:To produce externally a counterelectromotive force generated in an armature coil out of a motor by providing the third brush between positive and negative brushes disposed near the magnetic neutral axis of a field. CONSTITUTION:The third brush 3 is disposed at the position having an angle theta between positive and negative brushes 1 and 2 arranged near a magnetic neutral axis of a field F of the armature M of a DC motor. When a current is flowed from a power source 8 to between the brushes 2 and 3, a voltage in response to the rotating speed is generated between the brushes 1 and 2. Control signal generating means 6 applies a control signal to power control means 7 in response to a deviation between the voltage of the brush 1 and the speed set voltage from speed setting means 5 to control the rotating speed of a DC motor. |
