Liquid discharging apparatus and liquid filling method
US-2021394522-A1 · Dec 23, 2021 · US
Head unit and liquid ejection apparatus
US12485669B2 · US · B2
| Field | Value |
|---|---|
| Publication number | US-12485669-B2 |
| Application number | US-202418611784-A |
| Country | US |
| Kind code | B2 |
| Filing date | Mar 21, 2024 |
| Priority date | Mar 23, 2023 |
| Publication date | Dec 2, 2025 |
| Grant date | Dec 2, 2025 |
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- Title
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- Abstract
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Abstract
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A head unit includes a piezoelectric element displaced according to a driving signal to cause a liquid to be ejected, a driving signal generation unit that generates the driving signal, a residual vibration signal generation circuit that outputs a change in an electromotive force of the piezoelectric element according to residual vibration, in a pressure chamber in communication with a nozzle, that occurs after supply of the driving signal, as a residual vibration signal, an analog differential residual vibration signal generation circuit that converts the residual vibration signal into an analog differential residual vibration signal, a demodulation circuit that demodulates the analog differential residual vibration signal and outputs a demodulated signal, an AD converter that converts the demodulated signal into a digital signal, and a determination unit that determines, based on the digital signal, a state in the pressure chamber.
First claim
Opening claim text (preview).
What is claimed is: 1 . A head unit comprising: a piezoelectric element displaced according to a driving signal to cause a liquid to be ejected; a driving signal generation unit that generates the driving signal; a residual vibration signal generation circuit that outputs a change in an electromotive force of the piezoelectric element according to residual vibration, in a pressure chamber in communication with a nozzle, that occurs after supply of the driving signal, as a residual vibration signal; an analog differential residual vibration signal generation circuit that converts the residual vibration signal into an analog differential residual vibration signal; a demodulation circuit that demodulates the analog differential residual vibration signal and outputs a demodulated signal; an AD converter that converts the demodulated signal into a digital signal; and a determination unit that determines, based on the digital signal, a state in the pressure chamber. 2 . The head unit according to claim 1 , wherein the analog differential residual vibration signal generation circuit is composed of a discrete component. 3 . The head unit according to claim 1 , wherein the analog differential residual vibration signal generation circuit is composed of an IC component. 4 . The head unit according to claim 1 , further comprising: a first substrate on which the analog differential residual vibration signal generation circuit is mounted; and a second substrate on which the demodulation circuit is mounted, wherein the first substrate is different from the second substrate. 5 . The head unit according to claim 4 , wherein the AD converter is mounted on the second substrate. 6 . The head unit according to claim 4 , wherein the residual vibration signal generation circuit is mounted on the first substrate. 7 . A liquid ejection apparatus comprising: a transport mechanism; and a head unit, wherein the head unit includes a piezoelectric element displaced according to a driving signal to cause a liquid to be ejected, a driving signal generation unit that generates the driving signal, a residual vibration signal generation circuit that outputs a change in an electromotive force of the piezoelectric element according to residual vibration, in a pressure chamber in communication with a nozzle, that occurs after supply of the driving signal, as a residual vibration signal, an analog differential residual vibration signal generation circuit that converts the residual vibration signal into an analog differential residual vibration signal, a demodulation circuit that demodulates the analog differential residual vibration signal and outputs a demodulated signal, an AD converter that converts the demodulated signal into a digital signal, and a determination unit that determines, based on the digital signal, a state in the pressure chamber. 8 . The liquid ejection apparatus according to claim 7 , wherein the analog differential residual vibration signal generation circuit is composed of a discrete component. 9 . The liquid ejection apparatus according to claim 7 , wherein the analog differential residual vibration signal generation circuit is composed of an IC component. 10 . The liquid ejection apparatus according to claim 7 , further comprising: a first substrate on which the analog differential residual vibration signal generation circuit is mounted; and a second substrate on which the demodulation circuit is mounted, wherein the first substrate is different from the second substrate. 11 . The liquid ejection apparatus according to claim 10 , wherein the AD converter is mounted on the second substrate. 12 . The liquid ejection apparatus according to claim 10 , wherein the residual vibration signal generation circuit is mounted on the first substrate.
Assignees
Inventors
Classifications
Structure of print heads with piezoelectric elements · CPC title
characterised by jet control (B41J2/205 takes precedence) · CPC title
- B41J2/01Primary
Ink jet · CPC title
Specific driving circuit · CPC title
for detecting failure, e.g. clogging, malfunctioning actuator · CPC title
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Frequently asked questions
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- What does patent US12485669B2 cover?
- A head unit includes a piezoelectric element displaced according to a driving signal to cause a liquid to be ejected, a driving signal generation unit that generates the driving signal, a residual vibration signal generation circuit that outputs a change in an electromotive force of the piezoelectric element according to residual vibration, in a pressure chamber in communication with a nozzle, …
- Who is the assignee on this patent?
- Seiko Epson Corp
- What technology area does this patent fall under?
- Primary CPC classification B41J2/01. Mapped technology areas include Operations & Transport.
- When was this patent published?
- Publication date Tue Dec 02 2025 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
- What related patents are in patentsdb?
- We list 3 related publications on this page (citations in our corpus or others sharing the same primary CPC).