| 摘要 |
PURPOSE:To prevent the flow of ink from running in a reverse direction to an ink chamber, by providing a check valve in a passage communicating a pressure chamber with the ink chamber of a printer head. CONSTITUTION:When a pulse signal at a predetermined voltage is applied to a piezoelectric ceramic 33, the capacity of a pressure chamber 25 is reduced thereby to cause a predetermined amount of ink 34 to be jetted from a nozzle 24. At a next moment, a pressure plate 15 is returned to an original shape, and further expanded outwards. At the same time, a valve body 30 constituting a check valve or non-return valve is opened, so that the pressure chamber 25 is communicated to an ink chamber via a passage 31 and a notch 32. Consequently, the ink is injected into the pressure chamber 25, without the air being sucked in from the nozzle 24. When the pressure plate 15 is returned back to the original shape again, the valve body 30 closes the passage 31 simultaneously. As a result, the ink is prevented from running in a reverse direction to the ink chamber through the passage 31 and the notch 32. Accordingly, the propulsion because of the deformation of the piezoelectric ceramic can be fully utilized as an energy for ejecting the ink. |
