An imaging apparatus capable of suppressing inadvertent ejection of a satellite ink droplet therefrom and method of assembling same

摘要

An imaging apparatus capable of suppressing inadvertent ejection of a satellite ink droplet (22) and method of assembling the apparatus. The imaging apparatus comprises a print head transducer (160) including a pair of sidewalls (180, 190) defining a chamber (170) therebetween, the channel having an ink body (200) disposed therein. The transducer is capable of inducing a first pressure wave (300) in the ink body in order to eject an intended ink droplet (20). A waveform generator (80) is connected to the transducer for supplying a voltage waveform (290) to the transducer, so that the transducer induces pressure waves in the ink body to eject the ink droplet. However, the first pressure wave has a reflected portion (310) formed by the first pressure wave reflecting from the sidewalls. The reflected portion is sufficient to inadvertently eject unintended satellite ink droplets following ejection of the intended ink droplet (20). To avoid formation of satellite ink droplets, a sensor (320) is in fluid communication with the ink body for sensing the reflected portion. A feedback circuit (340) interconnects the transducer and the sensor for inducing a second pressure wave (360) in the ink body in response to the reflected portion sensed by the sensor. The second pressure wave has an amplitude and phase damping the reflected portion of the first pressure wave in order to the suppress inadvertent ejection of the satellite ink droplets.