| 摘要 |
PURPOSE:To enable efficient detecting of a liquid level by means of a steady detecting signal having a high redundancy, by a method wherein 2 bimorph elements of an element for vibration-generating and an element for vibration- detecting are mounted in an adjacent manner and adhered firmly to an outer wall surface of a printing head. CONSTITUTION:Through application of a voltage to a bimorph element 6 for vibration-geneating from a pulse generator 203, an upper plate 202 is vibrated, and a vibration-detecting voltage from a bimorph element 7 for vibration-generating is binary-coded by a binary code circuit 204. A detecting signal 300 in the case of ink positioned at a level of an ink tank part (an uppermost part of an ink tank 5) located adjacent to the elements 6 and 7 widely differs from a detecting signal 301 in the case of no ink positioned thereat. This allows the elements 6 and 7 to decide whether an ink liquid level in the ink tank 5 is positioned in an upper or a lower level. |
