摘要 |
PROBLEM TO BE SOLVED: To provide an electrostatic actuator capable of generating an always desired pressure with being affected by a variation in an external atmospheric pressure and an electrostatic liquid injection device capable of appropriately discharging liquid droplets. SOLUTION: The electrostatic ink jet head 1 comprises pressure chambers 6 communicating with ink nozzles 21 and an atmospheric pressure chamber 12 open to the atmosphere, wherein diaphragms 5 are formed on the bottom surfaces of the pressure chambers 6, a voltage is applied between the diaphragms 5 and discrete electrodes 43 to vibrate the diaphragms 5 electrostatically so as to inject ink droplets, vibration chambers 41 communicate with a pressure compensating chamber 49, a displacement plate 16 which is displaceable toward the outside of the bottom surface of the pressure compensating chamber 49 according to a variation in atmospheric pressure is formed on the bottom surface of the pressure compensating chamber 49, the volume of the pressure compensating chamber 49 is increased or decreased according to the displacement of the displacement plate 16 so that the inside pressure of each vibration chamber 41 communicating with the pressure compensating chamber 49 is regulated to the atmospheric pressure. COPYRIGHT: (C)2009,JPO&INPIT |