| 摘要 |
<p>PURPOSE:To prevent generation of printing irregularity, by providing a pulse non-applying means for providing a non-applying state, which applies no pulse during each pulse applying period applying the pulse corresponding to each line, to a plurality of heat generating resistors. CONSTITUTION:In a thermal head driving apparatus wherein a large number of heat generating resistors arranged in one row in a thermal head 13 are divided into at least two or more blocks and a pulse is applied to a plurality of the heat generating resistors while the blocks are successively changed at every gradation pulses, a pulse non-applying means is mounted. That is, the heat generating resistors in the thermal head 13 become a cooling period during each pulse applying period for applying the pulse corresponding to each line to a plurality of the heat generating resistors, because the strobe signal from a frequency divider 18 becomes disable and no pulse is applied. Therefore, the heat accumulation of the thermal head 13 is prevented and printing irregular ity can be eliminated.</p> |
