| 摘要 |
PURPOSE:To make the miniaturization and weight lightening of a device possible, by providing the means by which the vibration state of the piezoelectric element so attached as to touch ink is detected. CONSTITUTION:The pickup made of a piezoelectric element 4 is established at a height corresponding to a specific liquid surface level on the side wall 7 of an ink tank 1. Because the piezoelectric element 4 is so arranged as to be able to touch the ink 2 in the ink tank 1 via a thin film 5, a broad range of ink 2 comes to participate in the vibration of the element and the vibration conditions of the element is greatly changed according to the presence of ink. Therefore, the remaining amount of the ink can be detected by measuring the output of detection with a frequency counter or the like and an operator can be inspired to supplement ink with a buzzer, an alarm lamp, etc. |
