US 12,030,314 B2
Liquid ejection head
Meng Fei Wong, Mishima Shizuoka (JP); and Yuji Shinomiya, Mishima Shizuoka (JP)
Assigned to Toshiba Tec Kabushiki Kaisha, Tokyo (JP)
Filed by TOSHIBA TEC KABUSHIKI KAISHA, Tokyo (JP)
Filed on Jun. 15, 2022, as Appl. No. 17/841,634.
Claims priority of application No. 2021-209471 (JP), filed on Dec. 23, 2021.
Prior Publication US 2023/0202172 A1, Jun. 29, 2023
Int. Cl. B41J 2/14 (2006.01); B41J 2/045 (2006.01); B41J 2/175 (2006.01)
CPC B41J 2/14201 (2013.01) [B41J 2/04588 (2013.01); B41J 2/17596 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A liquid ejection head, comprising:
a nozzle from which a droplet of a liquid can be ejected;
a pressure chamber for the liquid, the pressure chamber connected to the nozzle;
an actuator configured to change a volume of the pressure chamber according to a voltage signal applied to the actuator; and
a drive circuit configured to generate the voltage signal that includes (n−1) ejection pulses when droplets are to be ejected n times from the nozzle, where n is an integer of 3 or more, wherein
the ejection pulses include:
a first ejection pulse that lowers a voltage applied to the actuator to a first voltage value to expand the pressure chamber and then raises the voltage to a second voltage value to contract the pressure chamber, and
a second ejection pulse that lowers the voltage to the first voltage value and then raises the voltage to a third voltage value higher than the second voltage value,
the ejection pulses are separated by intervals of 0.8λ to 1.2λ, where λ is a period of a primary natural vibration for the pressure chamber filled with the liquid,
the voltage signal further includes a cancel pulse following the ejection pulses,
a last ejection pulse of the ejection pulses is the second ejection pulse by which the voltage is raised to the third voltage value,
the cancel pulse lowers the voltage to a voltage value lower than the second voltage value and then raises the voltage to the second voltage value, and
the cancel pulse is input after the voltage is lowered from the third voltage value to the second voltage value.