| 摘要 |
PURPOSE:To prevent the electrolysis of ink from causing a change in component, generation of gas, and formation of polarization film on electrodes by a method wherein a remaining amount of ink in an ink tank is detected in accordance with a change in impedance detected by applying a voltage pulse between electrodes. CONSTITUTION:In an ink tank, a plurality of electrodes 5a, 5b and a voltage restriction part between the electrodes 5a, 5b are provided. By applying a voltage pulse between the electrodes 5a, 5b, an impedance inside the ink tank 1 is detected. In accordance with a change in impedance, a remaining amount of ink inside the ink tank 1 is detected. Because a voltage is restricted by a detection level of impedance inside the ink tank 1, an electric energy to be applied to a foam 4 impregnated with water-soluble ink is remarkably reduced. Therefore, an electrolysis of ink never causes a change in component, a generation of gas, and a change in signal level caused by forming of a polarization film on a detected part. A remaining amount of ink can be electrically detected. |
