Liquid discharging apparatus, liquid discharging head, and method for driving liquid discharging head

Patent metadata

Field	Value
Publication number	US-10906303-B2
Application number	US-201916575905-A
Country	US
Kind code	B2
Filing date	Sep 19, 2019
Priority date	Sep 28, 2018
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

A liquid discharging apparatus includes a liquid discharging head that discharges liquid from a nozzle, and a driving signal substrate that inputs, to the liquid discharging head, a driving signal according to waveform data. The liquid discharging head includes a driving element that drives the nozzle, switching elements connected to the driving element, a signal transmitter connected to the driving element via the switching elements and including signal lines through which the driving signal is transmitted according to waveform data, and a potential difference detector that detects a potential difference based on an intermediate potential of the driving signal transmitted through each signal line. The liquid discharging apparatus generates a correction signal based on the potential difference; corrects the waveform data based on the correction signal; generates the driving signal based on the corrected waveform data; and outputs the generated driving signal to the corresponding signal line.

First claim

What is claimed is:

1. A liquid discharging apparatus comprising:
a liquid discharging head configured to discharge liquid from a nozzle;
a driving signal substrate configured to input, to the liquid discharging head, a driving signal according to waveform data;
a driving element configured to drive the nozzle;
a plurality of switching elements connected in parallel to the driving element;
a first signal transmitter connected to the driving element via the plurality of switching elements and formed of a plurality of signal lines through which the driving signal is transmitted;
a switching controller configured to perform switching control to selectively turn on one of the plurality of switching elements;
a potential difference detector configured to detect a potential difference based on an intermediate potential of the driving signal transmitted through each of the plurality of signal lines;
a correction signal generator configured to generate a correction signal based on the potential difference;
a correction processor configured to correct the waveform data based on the correction signal; and
a driving signal generator provided to each of the plurality of signal lines and configured to generate the driving signal based on the waveform data corrected by the correction processor and to output the generated driving signal to a corresponding signal line among the plurality of signal lines.

2. The liquid discharging apparatus according to claim 1 , wherein the correction processor includes an offset correction processor configured to perform offset correction to correct the waveform data so as to eliminate the potential difference, based on the correction signal.

3. The liquid discharging apparatus according to claim 2 , wherein the correction processor further includes a voltage multiplication correction processor configured to perform voltage multiplication correction by multiplying waveform data, which is obtained by subtracting an ideal potential from the waveform data that has undergone the offset correction, by a voltage multiplying factor, and adding the ideal potential.

4. The liquid discharging apparatus according to claim 1 , wherein
the driving signal generator outputs the driving signal based on the waveform data that cyclically differs in a predetermined discharge cycle, and
the driving signal to be input to the driving element is selected according to the switching control.

5. The liquid discharging apparatus according to claim 1 , further comprising:
a second signal transmitter configured to transmit the correction signal to the correction processor from the correction signal generator.

6. The liquid discharging apparatus according to claim 1 , wherein the detecting of the potential difference by the potential difference detector, the generating of the correction signal by the correction signal generator, and the correcting by the correction processor are executed for each discharge cycle.

7. The liquid discharging apparatus according to claim 1 , wherein the detecting of the potential difference by the potential difference detector, the generating of the correction signal by the correction signal generator, and the correcting by the correction processor are executed before an operation of recording an image onto a recording medium performed by the liquid discharging head.

8. The liquid discharging apparatus according to claim 1 , wherein the driving element is a piezoelectric element.

9. The liquid discharging apparatus according to claim 1 , wherein the potential difference is a potential difference between the intermediate potential and an ideal potential.

10. A liquid discharging head comprising:
a driving element configured to drive a nozzle configured to discharge liquid;
a plurality of switching elements connected in parallel to the driving element;
a first signal transmitter connected to the driving element via the plurality of switching elements and formed of a plurality of signal lines through which a driving signal is transmitted according to waveform data; and
a potential difference detector configured to detect a potential difference based on an intermediate potential of the driving signal transmitted through each of the plurality of signal lines.

11. A method for driving a liquid discharging head, the liquid discharging head including
a driving element configured to drive a nozzle configured to discharge liquid,
a plurality of switching elements connected in parallel to the driving element,
a first signal transmitter connected to the driving element via the plurality of switching elements and formed of a plurality of signal lines through which a driving signal is transmitted according to waveform data, and
a potential difference detector configured to detect a potential difference based on an intermediate potential of the driving signal transmitted through each of the plurality of signal lines, the method comprising:
generating a correction signal based on the potential difference detected by the potential difference detector;
correcting the waveform data based on the correction signal;
generating the driving signal based on the waveform data corrected by the correction signal; and
outputting the generated driving signal to a corresponding signal line among the plurality of signal lines.

Assignees

• OSANAI Shinichiroh
• Ricoh Co Ltd

Inventors

• OSANAI Shinichiroh

Classifications

• B41J2/04581 Primary

  controlling heads based on piezoelectric elements · CPC title

• B41J2/04555

  detecting current · CPC title

• B41J2/04541

  Specific driving circuit · CPC title

• B41J2/04588 Primary

  using a specific waveform · CPC title

• B41J2/0459

  Height of the driving signal being adjusted · CPC title