US Patent 7597428 Ink jet head

Disclosed is an ink jet head which can eject an ink droplet while preventing failure of ink ejection, resulting in printing an image having good print quality. The ink jet head comprises a plurality of pressure chambers, a nozzle fluidly communicating with respective pressure chamber, first common ink chamber provided on one edge of the pressure chamber, second common ink chamber provided on the other edge of the pressure chamber, and an ink channel fluidly communicating the first common ink chamber with the second. An ultrasonic transducer arranged in a part of the ink channel causes the ink in ink channel to circulate through a passage way formed of the ink channel, the first and second common, ink chambers and pressure chamber.