# US 2021/0276323 A1 · Liquid ejection apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0276323 A1 - Document ID: US20210276323A1 - Status: Published application - Kind: A1 - Application number: 17/166,865 - Filed: 2021-02-03 - Published: 2021-09-09 - Earliest claimed: 2020-03-04 - Assignees: Toshiba Tec Kabushiki Kaisha - Applicants: Toshiba Tec Kabushiki Kaisha - Inventors: Noboru NITTA - Web page: https://patentgrep.com/patent/US20210276323A1 ## CPC - B41J 2/04541: {Specific driving circuit} - B41J 2/04595: {Dot-size modulation by changing the number of drops per dot} - B41J 2/04573: {Timing; Delays} - B41J 2/04581: {controlling heads based on piezoelectric elements} - B41J 2/04588: {using a specific waveform} - B41J 2/14201: {Structure of print heads with piezoelectric elements} - B41J 2202/10: Finger type piezoelectric elements - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS ## Abstract A liquid ejection apparatus includes a liquid ejection unit with a plurality of nozzles and a corresponding plurality of actuators. A drive waveform generation circuit is configured to generate drive waveforms having different drive timings. An actuator drive circuit is configured to apply a first drive waveform to a first actuator in a liquid ejection operation and a second drive waveform to a second actuator in the liquid ejection operation during which the first and second actuators are to be driven at a same nominal time. The first driving waveform is different from the second drive waveform, and the first actuator is at a position electrically closer along a predetermined direction to a power supply electrode than is the second actuator. ## Claims ### Claim 1 A liquid ejection apparatus, comprising: a liquid ejection unit including a plurality of nozzles and a corresponding plurality of actuators; a drive waveform generation circuit configured to generate a plurality of drive waveforms having different drive timings; and an actuator drive circuit configured to apply a first drive waveform to a first actuator in a liquid ejection operation and a second drive waveform to a second actuator in the liquid ejection operation, wherein the first and second actuators are to be driven at a same nominal time during the liquid ejection operation, the first and second drive waveforms have different drive timings, and the first actuator is at a position electrically closer along a predetermined direction to a power supply electrode than is the second actuator. ### Claim 2 (depends on 1) The liquid ejection apparatus according to claim 1, wherein the actuator drive circuit is configured to set the second drive waveform by reference to the first drive waveform. ### Claim 3 (depends on 2) The liquid ejection apparatus according to claim 2, wherein the second actuator is the closest actuator to the first actuator along the predetermined direction. ### Claim 4 (depends on 3) The liquid ejection apparatus according to claim 3, wherein at least one actuator that is not to be driven at the same nominal time as the first and second actuators is between the first and second actuators. ### Claim 5 (depends on 1) The liquid ejection apparatus according to claim 1, wherein the second drive waveform has a phase opposite to that of the first drive waveform. ### Claim 6 (depends on 1) The liquid ejection apparatus according to claim 1, wherein the second drive waveform corresponds to the first drive waveform with a delay added thereto. ### Claim 7 (depends on 6) The liquid ejection apparatus according to claim 6, further comprising: a memory storing a delay allocation table, wherein the actuator drive circuit adds the delay based on the delay allocation table. ### Claim 8 (depends on 1) The liquid ejection apparatus according to claim 1, wherein each of the actuators has a first terminal connected to a common electrode and a second terminal connected to an individual electrode to which the drive waveforms are applied for each actuator. ### Claim 9 (depends on 8) The liquid ejection apparatus according to claim 8, wherein the power supply electrode is the common electrode. ### Claim 10 (depends on 9) The liquid ejection apparatus according to claim 9, wherein the first actuator is at an electrically closest position on the common electrode to the second actuator. ### Claim 11 A liquid ejection apparatus, comprising: a liquid ejection unit including a plurality of nozzles and a corresponding plurality of actuators; a drive waveform generation circuit configured to generate a plurality of drive waveforms having different drive timings; a plurality of pressure chambers, each pressure chamber being connected to a respective nozzle of the plurality of nozzles; and an actuator drive circuit configured to apply a first drive waveform to a first actuator in a liquid ejection operation and a second drive waveform to a second actuator in the liquid ejection operation, wherein the first and second actuators are to be driven at a same nominal time during the liquid ejection operation, the first and second driving waveforms have different drive timings, and the actuator drive circuit is configured to select the second drive waveform by reference to the first drive waveform applied to the first actuator. ### Claim 12 (depends on 11) The liquid ejection apparatus according to claim 11, wherein among the plurality of actuators to be driven at the same nominal time the second actuator is nearest to the first actuator along a predetermined direction corresponding to the direction in which a separation distance between pressure chambers is shortest. ### Claim 13 (depends on 12) The liquid ejection apparatus according to claim 12, wherein at least one actuator that is not to be driven at the same nominal time as the first and second actuators is between the first and second actuators along the predetermined direction. ### Claim 14 (depends on 12) The liquid ejection apparatus according to claim 12, wherein the second actuator is the physically closest actuator to the first actuator along a predetermined direction. ### Claim 15 (depends on 12) The liquid ejection apparatus according to claim 12, wherein the second drive waveform has a phase opposite to that of the first drive waveform. ### Claim 16 (depends on 12) The liquid ejection apparatus according to claim 12, wherein the second drive waveform corresponds to the first drive waveform with a delay added thereto. ### Claim 17 (depends on 16) The liquid ejection apparatus according to claim 16, further comprising: a memory storing a delay allocation table, wherein the actuator drive circuit adds the delay based on the delay allocation table. ### Claim 18 A method for ejecting liquid from a liquid ejection head, comprising: selecting a first actuator and a second actuator from among a plurality of actuators of a liquid ejection head which are to be driven at the same nominal time; applying first drive waveform to the first actuator; and applying a second drive waveform to the second actuator, wherein the first driving waveform is different from the second driving waveform, and the first actuator is at a position electrically closer along a predetermined direction to a power supply electrode than is the second actuator. ### Claim 19 (depends on 18) The method according to claim 18, wherein the second drive waveform has a phase opposite to that of the first drive waveform. ### Claim 20 (depends on 18) The method according to claim 18, wherein the second drive waveform corresponds to the first drive waveform with a delay added thereto.