| 摘要 |
PURPOSE:To automatically control the position of a rotor, while maintaining constant the positional relationship between the magnetic field induced in a stator and the magnetic field of the rotor by supplying the stator winding of a motor with signals of preset polarity. CONSTITUTION:When a VTR is brought inot a stop mode, 6TACH signals a are generated at the output of an amplifier 4 while a DC motor 8 is rotating by its inertia. When the DC motor 8 is stopped to generate none of the 6TACH dsgnals a, the output signals e of a rotation detecting circuit 18 are changed to an L level. A delay signal generating circuit 19 is triggered at the breaking edge of the output signals 3 of the circuit 18. Since in this instance, the delay of the circuit 19 if preset about two seconds, signals f are gnerated at the output of the circiut 19. As a redult, rotor position control signals h are generated at the output of a motor control singal generating circuit 20 so that the position of the rotor is aoutomatically moved. |
