| 摘要 |
PURPOSE: To prevent the damage of a printer by measuring the temp. of a printhead at a time of printing work and performing the correction o the intrusion of air into the printhead, that is, the refilling or replacement of ink when the measured temp. exceeds a predetermined threshold value. CONSTITUTION: A temp. sensor 52 of which the resistance value is changed by temp. is provided to a printhead substrate 50 and the dropped voltage between the temp. sensor 52 and a thermistor 62 is read through an A/D converter 64 to be inputted to a microprocessor 66. A threshold value calculated by adding equilibrium idle temp. to a constant threshold value delta 68 is inputted to the microprocessor 66. Then, the threshold value temp. is compared with data related to measured temp. by the microprocessor 66 and, when the threshold value temp. is higher, printing work is continued while, when the threshold value temp. is lower, the imperfect filling of ink or the reduction of an ink source is judged to perform the refilling or replacement of ink. |
