Patent ID: 6286923
Filing Date: 2001-09-11
Classification: B41J

Abstract:
An ink jet printer comprising;a print head for ejecting ink, the print head being formed with an ejection channel filled with ink and including an actuator for generating force to eject ink from the ejection channel, the actuator being formed from piezoelectric material that deforms upon application of drive pulses;a drive circuit that applies drive pulses to the actuator of the print head to drive the print head to eject ink from the ejection channel;a counter that counts a number of times the drive circuit drives the print head;a memory that stores, based on the number of times counted by the counter, a cumulative number of times that the drive circuit has driven the print head up to present; anda waveform change unit that, when the cumulative number of times stored in the memory exceeds a predetermined value, changes waveform of the drive pulse applied by the drive circuit to the print head, in order to increase force at which the print head ejects ink.