Patent ID: 7621609
Filing Date: 2009-11-24
Classification: B41J

Abstract:
1. An ink ejection device, comprising: a plurality of nozzles for ejecting ink drops; a plurality of pressure chambers respectively corresponding to the plurality of nozzles; an actuator capable of changing capacity of each of the plurality of pressure chambers; a controlling device that applies a drive pulse signal to the actuator at every predetermined ejection cycle to change the capacity of each pressure chamber to make each nozzle eject an ink droplet, the drive pulse signal being selected in accordance with dot information indicating dots to be formed on a recording medium successively in a direction of a relative movement of the plurality of nozzles with respect to the recording medium, wherein the controlling device includes: wherein, when the dot information for the current ejection cycle and the dot information for the succeeding ejection cycle indicate a first condition where ejection of a maximum amount of an ink drop and no ejection of an ink drop, respectively, the signal selecting system selects two kinds of drive pulse signals for the current ejection cycle and the succeeding ejection cycle, respectively, such that the selected drive pulse signals are different from drive pulse signals for a second condition in which the dot information for the current ejection cycle indicates ejection of a maximum amount of an ink drop and the dot information for the succeeding ejection period indicates ejection of an ink drop, and wherein the signal output system outputs the two kinds of drive pulse signals for the current ejection cycle and the succeeding ejection cycle within the current ejection cycle and in the succeeding ejection cycle, respectively.