| 摘要 |
PURPOSE:To control feeding velocity of a recording paper and detect defective feeding with a simple feeding passage construction, by providing a detector in a feeding passage extended to a thermal head. CONSTITUTION:The recoding paper 2 is normally fed out from a paper-supplying tray 1, and a pulse signal with a frequency corresponding to the feeding velocity of the paper 2 is generated by a rotary encoder fitted to a rotary shaft of a velocity-detecting roller 10. The signal is fed to a discriminator through a calculator, and whether or not mis-feeding is generated is discriminated by discriminating whether or not the pulse signal from the rotary encoder has arrived by the time a period of time set on a timer elapses. A value obtained by converting the pulse signal from the encoder into the number of motor pulses is inputted into the calculator, and a comparator corrects the period of the motor pulses generated by a motor pulse generator in accordance with a deviation. Accordingly, the feeding velocity of the paper 2 passed through the thermal head 4 is perfectly synchronized with the recording speed of the head 4. |
