| 摘要 |
A small-sized printer having print characters circumferentially disposed around a plurality of print rings rotating by a motor on a common shaft, includes a detector comprised of an integrated circuit board rotating on the same shaft. The rotating circuit board incorporates conductive foil contacts which are sensed during rotation by fixed brushes, thereby providing a series of pulses indicative of the rotational position of the shaft and of the print characters which are in position for printing. An auxiliary signal, generated by additional contacts on the rotating circuit board, indicate positions between the print characters on the print rings. Logic circuitry combines the actual position pulses with the auxiliary signals to output converted position pulses which are free of noise and irregularities in waveform normally associated with brush contact switches. These converted pulses provide accurate timing as is required for the print cycle. A motor stop signal is also provided.
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