| 摘要 |
PURPOSE:To always stop the drive shaft of a motor in the prescribed rotating angle by detecting the rotating speed of a motor when a power source is OFF and applying a stopping voltage for stopping the inertial rotation of the motor during a period of the length substantially inversely proportional to the detected rotating speed. CONSTITUTION:A sheet feed pulley 2 is rotatably supported to a frame 1, and a spur gear 3 is fixed to one end of the pulley 2. A drive shaft 5 which is engaged with the gear 3 is provided perpendicularly to the axial direction of the pulley 2 on a supporting base 4 fixed to the frame 1, and a motor M is connected to the shaft 5. A sector detecting plate 7 is secured to the shaft 5, and a frame 8, in which a light emitting element LD and a photodetector FT are opposed at the rotary path of the plate 7 on the upper surface of the base 4. The output of the photodetector FT is applied through an amplifier AP through an I/O port and a counter CNT. A microcomputer MC applies a stopping voltage in response to the rotating speed of the motor M when the power source is OFF through a time drive circuit DR in the length substantially inversely proportional to the detected rotating speed, thereby stopping the motor drive shaft within the prescribed rotating angle. |
