Patent ID: 6231150
Filing Date: 2001-05-15
Classification: B41J

Abstract:
An ink-jet printing apparatus comprising:a printing head having an ink channel, an actuator for changing a volume of the ink channel and a nozzle connected with the ink channel to eject the ink from the ink channel onto a printable medium; anda drive circuit connected to the printing head for applying a drive pulse signal including a first drive pulse to the actuator so that the ink channel expands a volume thereof to generate a pressure wave in the ink channel and, after a lapse of an approximate odd-numbered multiple of one-way propagation time T of the pressure wave in the ink channel, an expanded volume of the ink channel is decreased to normal state thereof to apply pressure to the ink in the ink channel for ejecting the ink from the ink channel through the nozzle,wherein the drive circuit, after applying the first drive pulse to the actuator, applies to the actuator a second drive pulse which has a magnitude substantially equal to that of the first drive pulse and a pulse width equal to approximately 0.20 to 0.40 times the one-way propagation time T so that an end time of the second drive pulse falls in a range of approximately 2.60 to 2.80 times the one-way propagation time T from an end time of the first drive pulse.