Patent ID: 8277008
Filing Date: 2012-10-02
Classification: B41J

Abstract:
1. A method for driving an inkjet head, comprising the step of applying drive signals including an ejection signal used for ejecting ink and a non-ejection signal used for not ejecting the ink, to an actuator provided with a pressure chamber at a constant cycle so as to increase or reduce pressure in the pressure chamber in such a manner that the ink is ejected or not ejected from a nozzle connected with the pressure chamber, wherein: a waveform of the ejection signal includes a combination of an ejection pulse for causing a droplet of the ink to be ejected from the nozzle and a non-ejection pulse for not causing a droplet of the ink to be ejected from the nozzle, the ejection pulse of the waveform of the ejection signal includes a part for reducing the pressure in the pressure chamber and a part for increasing the reduced pressure in the pressure chamber, the non-ejection pulse of the waveform of the ejection signal includes a part for reducing the pressure in the pressure chamber and a part for increasing the reduced pressure in the pressure chamber, the part for reducing the pressure in the pressure chamber of the non-ejection pulse of the waveform of the ejection signal is set to reduce the pressure in the pressure chamber while a tail of a droplet of the ink ejected from the nozzle by the ejection pulse is connected to the nozzle, the part for increasing the pressure in the pressure chamber of the non-ejection pulse of the waveform of the ejection signal is set to increase the pressure in the pressure chamber within a resonance period of the pressure chamber from a moment when the pressure in the pressure chamber is increased by the ejection pulse, and the non-ejection signal has a waveform including only a non-ejection pulse including a part for reducing the pressure in the pressure chamber and a part for increasing the reduced pressure in the pressure chamber, not to cause a droplet of the ink to be ejected from the nozzle.