| 摘要 |
<p>An ink jet nozzle unit (10-14) is provided with an ink-shortage-detecting thorough hole comprising nozzle-shaped thorough holes (21,23), filter (25) and nozzle passage (26) and also with a pair of electrodes (17,18) in the middle thereof. This thorough hole, communicating with other nozzle passages including passage (24) equipped with PZT (15), is usually filled with ink, while the air is introduced into the thorough hole via orifice in the absence of ink. <IMAGE></p> |
