| 摘要 |
PROBLEM TO BE SOLVED: To detect run out of ink with high reliability by providing a first electrode to be connected with a known input signal, a second electrode patterned on an ink tank for detecting the input signal, and means for amplifying a signal detected by the second electrode and comparing it with a criterion thereby enhancing assembling performance. SOLUTION: A pulse signal 103 inputted to a head section 102 through a flex 101 propagates to the wall face 105 of an ink tank 104 through a conductive medium, i.e., an ink in the ink tank. A signal is then transmitted to a solid pattern electrode 106 on the flex 101 disposed contiguously to the wall face 105 of ink tank and inputted to an OP AMP 108 on a substrate 107 through the flex 101 and amplified. An output signal 109 from the AMP 108 is subjected to sample & hold before being inputted to A/D of a CPU. The CPU compares it with a criterion in order to detect run out of ink and an ink run out detection color is selected by switching a head for inputting a pulse signal by means of a switch 110. |
