| 摘要 |
<p>PURPOSE:To shorten the printing cycle by reducing energy to be applied onto respective heating elements gradually with time after throw-in of predetermined high temperature heating energy and controlling the temperature of the heating elements from high level to low level, thereby shortening the cooling time of head. CONSTITUTION:Power conduction pulses are applied sequentially onto respective blocks of split heating elements 5, 6. Such number of pulses as necessary for predetermined gradation are applied. Then such number of pulses as necessary for lower gradation are applied. Since energy is applied sequentially from high gradation to low gradation in one line, the temperature of heating element rises to the highest level immediately after application of energy and lowers gradually as the printing density is controlled until application of energy is finished. Consequently, the time required for cooling a head to the temperature with which next line is printed is shortened resulting in shortening of printing cycle.</p> |
