Ink jet printhead having an ultrasonic maintenance system incorporated therein and an associated method of maintaining an ink jet printhead by purging foreign matter therefrom

摘要

An ink jet printhead having an ultrasonic maintenance system incorporated therein and an associated method of maintaining an ink jet printhead by purging foreign matter therefrom. To forcibly eject foreign matter from an ink-carrying channel, the ink jet printhead is ultrasonically vibrated at a frequency of at least 20 kHz. Vibration may be initiated upon cessation of print operations or at selected time intervals for selected periods of time and may take place while the ink jet printhead is located within a print area portion of an associated ink jet printer where print operations are conducted or after the ink jet printhead is shuttled to a maintenance area. Foreign matter may also be ejected by applying a purging pulse to the ink-carrying channel. The purging pulse is generated by applying a voltage differential to a sidewall actuator laterally bounding the ink-carrying channel which is twice the magnitude of the voltage differential applied to eject a droplet of ink from the ink-carrying channel. The ink jet printhead may also be heated during the ultrasonic vibration thereof./!