| 摘要 |
PURPOSE:To enable high speed printing reliably and cleanly by initially applying a high voltage onto a thermal head for every dot printing then controlling such that a low voltage is applied. CONSTITUTION:A print control section 1-1 feeds head power conduction data to a latch 3 so as to ground a predetermined thermal head 6 while a voltage switching section 1-2 initially feeds an L-level voltage switching signal then an H-level (open level) voltage switching signal to the base of a transistor TR. Consequently, a high voltage to be applied initially from a high voltage power source VH through the transistor TR, a diode D and a connector 5 onto the thermal head 6 is switched to a low voltage from a low voltage power source VL. As a result, the time interval for holding the temperature at a higher level than the fusing temperature of the ink of ribbon is increased, resulting in a reliable and clean high speed printing. |
