| 摘要 |
PURPOSE: To detect the position and number of revolutions of a rotor by constituting a track for a signal, and generating voltage levels of three different amplitudes. CONSTITUTION: An optical unit 8 is assembled with the housing 5 of a motor 1, optical fiber communication lines 9, 10, 11 having forward and return paths are connected to the unit 8, and tracks 14, 15, 16 for signals are formed as concentric rings on the end face 32 of a rotor. When lights are emitted from optical signal transmitters 20, 21, 22 during the operation and emitted to the tracks 14, 15, 16 via the forward paths of the lines 9, 10, 11, the reflected lights are guided to three photodiodes via the return path. In this case, when first, second and third regions are provided on the tracks 14, 15, 16 and white and back are formed, a rectangular wave pulse train having voltage levels of three different amplitudes are generated, and the identification of the position of the rotor and the detection of the number of revolutions can be conducted by an evaluating circuit 19. |
