| 摘要 |
PURPOSE:To improve the responding ability at high speeds in ejecting ink, by adding electric signals to piezoelectric elements respectively corresponding to a main and a sub pressuring chambers, with a shift of timing. CONSTITUTION:When an electric signal is added to a piezoelectric element 23, a vibrating plate 22 where the element 23 is provided displaces inwards of a main ink pressuring chamber 11, thereby to reduce the volume of the chamber 11 suddenly. As a result, ink liquid is ejected outside from a nozzle 21. Thereafter, when the electric signal is removed, the volume of the main ink pressuring chamber 11 is recovered. As the part of the vibrating plate 22 displacing to the main ink pressuring chamber 11 is returned to the original position, the other parts of the plate 22 corresponding to sub ink pressuring chambers 12, 13 are shifted inwards of the chamber 11 with the same timing as the above returning timing, so that the volume of each chamber 12, 13 is reduced. Thus, an extraordinary retreat of a miniscus in the ink nozzle 21 due to the sudden reduction of the volume of the main chamber 11 can be avoided. Accordingly, no troubles result from the suction of air. |
