| 摘要 |
PURPOSE:To dispense with re-adjustment by eliminating the irregularity of printing density, by providing a thermistor and a plurality of strap means displaying the irregularity of the resistance value of the thermistor at arbitrary temp. in a head main body. CONSTITUTION:There is irregularity of about + or -15% in the resistance of the temp. detecting thermistor of a thermal head and, if the thermal head is different, an error is generated in the control of printing density. For example, four strap terminals (a)-(c) are arranged to enable not only the setting of 16 stages of binary values but also the correction of irregularity at every 1kOMEGA in a range of 22-37kOMEGA. In strap disposition when the resistance of the certain one thermistor at 25 deg.C is set to 25kOMEGA, the terminals (c), (d) are strapped to the ground and the terminals (a), (b) are set to an open state to output the binary value '3' to 01-04 and the correction value of the printing driving pulse in a printing control part 2 comes to a pulse width wherein +25muS was added to a nominal pulse width and a heat generating resistor 4 is driven. By the above mentioned method, the error in printing control due to the irregularity of a thermistor resistance value can be corrected. |
