| 摘要 |
PURPOSE:To make a selection from among different types of ink film regardless of its resistance value by detecting the resistance value of ink film and controlling a voltage to be applied to the ink film based on the resistance value. CONSTITUTION:A driver Tr 22 is turned ON by connecting a signal to the driver Tr 22 from CPU 25. If the driver Tr 22 is set to 'ON' position, a voltage is applied to an energization head 102, which, in turn, runs an electric current (i) to an ink film 100. Subsequently, a potential difference is generated between voltage detection resistors RG. A voltage at point A is applied to one of input terminals of an OP amplifier 24 through a resistor, and the differential portion between said voltage and a reference voltage which is already applied to the other input terminal of the OP amplifier 24 is amplified and the amplified differential portion is applied to an A/D converter 23. CPU 25 reads a voltage which is converted to a digital signal DV by the A/D converter 23 and detects the resistance value of ink film 100. Then CPU 25 controls a voltage applied to the energization head 102 based on the detected resistance value of the ink film 100. |
