Patent ID: 7150513
Filing Date: 2006-12-19
Classification: B41J

Abstract:
1. A droplet ejection apparatus having a head unit including a plurality of droplet ejection heads each ejecting liquid within a cavity through a nozzle in the form of droplets by driving an actuator by way of a driving circuit, said apparatus comprising: ejection failure detecting means for detecting an ejection failure of said droplet ejection heads and a cause thereof; and recovery means for performing recovery processing depending on the cause of the ejection failure if said ejection failure detecting means detects the ejection failure; wherein each of said droplet ejection heads includes a diaphragm that is displaced when the actuator is driven and said ejection failure detecting means detects a residual vibration of said diaphragm and determines an ejection failure of said droplets based on a vibration pattern of the detected residual vibration of said diaphragm; wherein said ejection failure detecting means includes judging means for judging at least one of a presence and an absence of an ejection failure of the droplets in the corresponding droplet ejection head based on the vibration pattern of the residual vibration of said diaphragm, and judging the cause of the ejection failure upon judging the presence of the ejection failure of the droplets in said droplet ejection head, said vibration pattern of the residual vibration of said diaphragm including a cycle of the residual vibration; and wherein said judging means judges that: