| 摘要 |
<p>PURPOSE:To provide a recorder free from breakage of heaters or the like and enhanced in the useful life of a head and reliability, wherein when passing driving pulses to electro-thermal converters, driving pulses having a frequency and a pulse width of not smaller than predetermined values are inhibited from being impressed on heaters. CONSTITUTION:In a recorder so designed as to record by generating heat from electro-thermal converters, the period (t) for which an output l2 of a monostable multivibrator 4 is maintained at a low level is so set as to satisfy the relationship t<T-tp, where T is the maximum printing period and tp is the width of a printing pulse, whereby normal printing is conducted in an ordinary period. When pulses having a frequency of not smaller than a normal value, a printing command pulse STB is inputted in a period of time shorter than the period (t) set on the multivibrator 4, and an output Q2 of a J-K flip-flop 3 is outputted in a manner similar to that at normal time, but the output l2 of the multivibrator 4 remains at the low level, so that an output l3 of an AND gate 5 becomes low level, and the pulses are not impressed on the heaters 9a-9n.</p> |
