| 摘要 |
PURPOSE:To secure a normal moving distance even if an original platen is pushed with a hand to increase the moving speed, by providing a moving distance control means and a moving speed control means. CONSTITUTION:An encoder 2 consisting of a Hall element is set to the revolving shaft of a DC motor M1 and generates a pulse signal proportional to the rotation number of this motor, and the moving distance of an original platen 26 is detected by the number of pulses generated by the encoder 2, and the moving speed of the original platen 26 is detected by pulse intervals. A waveform shaping circuit 4 converts the pulse signal of the encoder 2 to a square wave, and a signal of the fall (or the rise) is inputted to a microcomputer 3. The microcomputer 3 controls a driving means so that the moving member is moved at a prescribed target moving speed in case of the detected moving speed lower than the prescribed speed and power is not supplied to the motor in case of the detected moving speed higher than the prescribed speed. Thus, the speed is accurately detected to normally control the moving distance.
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