| 摘要 |
PURPOSE:To simplify the construction of a power source circuit part and enable to reduce the size of the part, by providing an impressed voltage correcting resistor for a common electrode for a heating element head part, in a plurality of rows of heating element head parts different in pattern. CONSTITUTION:A common electrode 7 for a 7-dot heating element head part 2 is connected directly to a terminal 9a for connection to an external system, while a common electrode 8 for a 24-dot heating element head part 3 is connected to the terminal 9a through the impressed voltage correcting resistor 10. By this, both of the head parts 2, 3 can be driven by power sources of the same voltage. The resistance 10 is formed of the same material as that for the head parts 2, 3, and can be easily provided in the same step as for the head parts 2, 3. The cross-sectional ara of the resistor 10 is set to be not smaller than 1mm.<2> so that the temperature of the resistor 10 itself is not raised to the color forming temperature of a thermal recording paper. Accordingly, the construction of the power source circuit part is simplified, and the size thereof can be reduced. |
