Patent ID: 7566109
Filing Date: 2009-07-28
Classification: B41J

Abstract:
1. A droplet ejection apparatus comprising: a plurality of droplet ejection heads, each of the droplet ejection heads including: a driving circuit which drives the actuator of each droplet ejection head; a residual vibration detector detecting a residual vibration of an electromotive voltage generated from the actuator after the actuator has been driven by the driving circuit; a pulse generator generating reference pulses; an information processor carrying out a computation for the number of reference pulses generated by the pulse generator based on the residual vibration of the electromotive voltage detected by the residual vibration detector; a time measurer measuring a lapsed time since the actuator has been driven by the driving circuit; a head failure judge judging a head failure in the droplet ejection heads based on the computation result of the information processor and the lapsed time measured by the time measurer; and a switch switching a connection of the actuator from the driving circuit to the residual vibration detector after carrying out the droplet ejection operation by driving the actuator.