US 12,447,741 B2
Liquid ejection apparatus and determination method capable of determining whether or not liquid filling of pressure chamber has been completed
Daichi Kawano, Osaka (JP); Takashi Inoue, Osaka (JP); Keisuke Maeyama, Osaka (JP); Tatsuya Nakagawa, Osaka (JP); Satoshi Morimoto, Osaka (JP); and Minori Yamamoto, Osaka (JP)
Assigned to KYOCERA Document Solutions Inc., Osaka (JP)
Filed by KYOCERA Document Solutions Inc., Osaka (JP)
Filed on Aug. 24, 2023, as Appl. No. 18/455,566.
Claims priority of application No. 2022-156452 (JP), filed on Sep. 29, 2022.
Prior Publication US 2024/0109308 A1, Apr. 4, 2024
Int. Cl. B41J 2/045 (2006.01); B41J 2/175 (2006.01)
CPC B41J 2/04581 (2013.01) [B41J 2/0451 (2013.01); B41J 2/17566 (2013.01); B41J 2002/17583 (2013.01)] 1 Claim
OG exemplary drawing
 
1. A liquid ejection apparatus comprising:
a nozzle configured to eject a liquid;
a pressure chamber communicating with the nozzle and configured to contain the liquid;
a piezoelectric element configured to change a pressure in the pressure chamber in response to an input of a drive signal;
an output processing portion configured to cause the piezoelectric element to output a first electric signal corresponding to vibration generated in the pressure chamber in response to the input of the drive signal to the piezoelectric element;
a determination processing portion configured to determine whether or not the pressure chamber is in a filled state in which the pressure chamber is filled with the liquid, based on a frequency of the first electric signal output by the output processing portion;
a band-pass filter configured to output a second electric signal obtained by removing a frequency component not included in a predetermined specific frequency band from the first electric signal in response to an input of the first electric signal; and
a comparator configured to output a pulse signal when the second electric signal exceeds a predetermined threshold value, wherein
the predetermined specific frequency band is a frequency band including a frequency of the first electric signal when the pressure chamber is in the filled state and not including a frequency of the first electric signal when the pressure chamber is not in the filled state, and
the comparator outputs the pulse signal to the determination processing portion when the second electric signal changes.