LIQUID EJECTING APPARATUS

• US 20190232656A1
• Filed: 01/29/2019
• Published: 08/01/2019
• Est. Priority Date: 01/31/2018
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: MATSUMOTO, Yusuke
• Granted Patent: US 10,639,892 B2
• Time in Patent Office: Days
• CPC Class Codes: B41J 2/04541 Specific driving circuit
• CPC Class Codes: B41J 2/0455 Details of switching sections of circuit, e.g. transistors
• CPC Class Codes: B41J 2/04551 using several operating modes
• CPC Class Codes: B41J 2/04581 controlling heads based on piezoelectric elements
• CPC Class Codes: B41J 2/04588 using a specific waveform
• CPC Class Codes: B41J 2/04593 Dot-size modulation by changing the size of the drop
• CPC Class Codes: B41J 2/04596 Non-ejecting pulses
• CPC Class Codes: B41J 2/14233 of film type, deformed by bending and disposed on a diaphragm

Abstract

A liquid ejecting apparatus includes a drive circuit in which a first voltage signal is output from an output terminal, a piezoelectric element that includes a first electrode to which the first voltage signal is supplied and a second electrode to which a second voltage signal is supplied and is displaced by a potential difference between the first electrode and the second electrode, a cavity which is filled with a liquid, a vibration plate that is provided between the cavity and the piezoelectric element, and a switch element that is electrically connected to the output terminal and the first electrode. The liquid ejecting apparatus has a mode in which the switch element is controlled to be turned off, and a voltage value of the first voltage signal is controlled to approximate a voltage value of the second voltage signal.

Claims

1. A liquid ejecting apparatus comprising:

a drive circuit in which a first voltage signal is output from an output terminal;

a piezoelectric element that includes a first electrode to which the first voltage signal is supplied and a second electrode to which a second voltage signal is supplied and is displaced by a potential difference between the first electrode and the second electrode;

a cavity which is filled with a liquid that is ejected from a nozzle in accordance with the displacement of the piezoelectric element;

a vibration plate that is provided between the cavity and the piezoelectric element; and

a switch element that is electrically connected to the output terminal and the first electrode,

wherein the liquid ejecting apparatus has a mode in which a liquid is not ejected, the switch element is controlled to be turned off, and a voltage value of the first voltage signal is controlled to approximate a voltage value of the second voltage signal.

2. The liquid ejecting apparatus according to claim 1,

wherein a plurality of the nozzles are provided at a density of 300 or more per inch, and

wherein a plurality of the piezoelectric elements are provided corresponding to the plurality of nozzles.

3. The liquid ejecting apparatus according to claim 1,

wherein printing is not performed on a medium in the mode.

4. The liquid ejecting apparatus according to claim 1,

wherein a third voltage signal having a voltage value higher than the voltage value of the first voltage signal and the voltage value of the second voltage signal is input to a node which is electrically connected to the output terminal and the switch element, via a resistance element.

5. The liquid ejecting apparatus according to claim 1,

wherein a resistance component of the piezoelectric element is larger than a resistance component when the switch element is turned off.

6. The liquid ejecting apparatus according to claim 1,

wherein the drive circuit includes

a feedback circuit that feeds back the first voltage signal which is output from the output terminal;

a modulation circuit that generates a modulation signal, based on an original signal which is a source of the first voltage signal and a signal which is obtained by feeding back the first voltage signal; and

an output circuit that generates the first voltage signal by amplifying and demodulating the modulation signal.