| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus and a method, for the measurement of the passage of time, as well as an ink-jet printer, in which safety in usage and treatment in disposal do not cause problems. SOLUTION: An electric double-layer capacitor 2 is charged with a power- supply voltage, while a charging effective signal is input to a charging control circuit 1. The charging effective signal is turned off after the printing operation of the ink-jet printer is finished or after the recovery operation of a print head is finished, and an electric charge in the electric double-layer capacitor 2 is discharged via a resistor 3. That a capacitor voltage becomes a reference voltage V1 or V2 or less is detected by a voltage-1 comparison circuit 4 and a voltage-n comparison circuit 5 The passage of time is measured on the basis of the relationship between a previously measured voltage drop and the passage of time. |
