| 摘要 |
PURPOSE:To moderate accumulation of heat in a head and make uniform printed density, by varying the heating value of a thermal head for each printing cycle. CONSTITUTION:In accordance with a printing command fed from a host computer 21, a CPU22 referrs to a printing pattern stored in an RAM26, and determines an optimum width of a pulse impressed on the thermal head 2 through a signal wire S2 and a driver 23. First, the CPU22 clears a heat cycle counter RAM26 provided in the RAM26 for discriminating whether the thermal printer 2 is in printing of an odd-number cycle or printing of an even-number cycle. Further, to discriminate information on the dots having generated heat in the preceding time, the CPU22 clears an area for storing dot information for each printing cycle. Then, whether the heat cycle is odd-number cycle or even-number cycle is discriminated on the basis of the content of the heat cycle counter in the RAM26. Hereinafter, a few steps are executed to moderate the accumulation of heat in the head. |
