Inkjet printing apparatus and control method of the inkjet printing apparatus

Patent metadata

Field	Value
Publication number	US-10759181-B2
Application number	US-201816022311-A
Country	US
Kind code	B2
Filing date	Jun 28, 2018
Priority date	Jul 7, 2017
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

Abstract

According to an aspect of the present invention, an inkjet printing apparatus includes a print head having an ejection opening surface on which ejection openings for ejecting ink are formed, a tank storing ink to be supplied to the print head, a supply flow path for supplying the ink from the tank to the print head, a collection flow path for collecting the ink from the print head to the tank, a supply pump provided in the supply flow path to supply the ink from the tank to the print head, a tank decompression pump which decompresses the inside of the tank, and a control unit which controls to drive the supply pump and the tank decompression pump to fill the collection flow path with ink.

First claim

What is claimed is:

1. An inkjet printing apparatus comprising:
a print head having an ejection opening surface on which ejection openings for ejecting ink are formed;
a tank storing the ink to be supplied to the print head;
a supply flow path for supplying the ink from the tank to the print head;
a collection flow path for collecting the ink from the print head to the tank;
a supply pump provided in the supply flow path to supply the ink from the tank to the print head;
a tank decompression pump which decompresses the inside of the tank;
a cap configured to cover the ejection opening surface; and
a control unit configured to control to cover the ejection opening surface with the cap during the print head is being filled with the ink, to control to separate the ejection opening surface and the cap when the print head is filled with the ink, and after the print head and the cap separated, to control to drive the supply pump and the tank decompression pump simultaneously so as to fill the collection flow path with the ink.

2. The inkjet printing apparatus according to claim 1 , further comprising a collection pump provided in the collection flow path to collect the ink from the print head to the tank,
wherein the control unit controls to deactivate the tank decompression pump and to drive the collection pump after the collection flow path is filled with the ink to circulate the ink through a circulation path which includes all of the tank, the supply flow path, the print head and the collection flow path.

3. The inkjet printing apparatus according to claim 2 , wherein the print head comprises pressure chambers which communicate with the ejection openings respectively and are filled with the ink to be ejected from the ejection openings respectively, and
the control unit controls to drive the supply pump and the collection pump to circulate the ink to pass through inside of the pressure chambers.

4. The inkjet printing apparatus according to claim 2 , wherein in a case where the ink is refilled after the ink is collected to the tank, the control unit controls to drive the collection pump to fill the collection flow path with the ink.

5. The inkjet printing apparatus according to claim 1 , further comprising:
a cap decompression pump connected to the cap and constructed to decompress the inside of the cap,
wherein before the start of ink filling operation of the collection flow path, the control unit controls to drive the supply pump and the cap decompression pump with the ejection opening surface covered with the cap to fill the print head with the ink.

6. The inkjet printing apparatus according to claim 5 , wherein the control unit controls to drive the cap decompression pump to communicate a flow path from the tank to the ejection openings.

7. The inkjet printing apparatus according to claim 5 , wherein the tank decompression pump is a common pump that also functions as the cap decompression pump.

8. The inkjet printing apparatus according to claim 7 , further comprising:
a first valve provided in a flow path connecting the cap decompression pump to the cap; and
a second valve provided in a flow path connecting the cap decompression pump to the tank,
wherein the cap decompression pump is connected to the tank, and
after the print head is filled with the ink, the control unit controls to close the first valve and open the second valve to fill the collection flow path with the ink.

9. The inkjet printing apparatus according to claim 5 , further comprising:
a check valve provided in the supply flow path between the tank and the supply pump to prevent the ink from flowing from the supply pump to the tank; and
a supply valve provided between the supply pump and the print head,
wherein before the supply flow path, the print head, and the collection flow path are filled with the ink, the control unit controls to drive the cap decompression pump with the supply valve closed and the ejection opening surface covered with the cap to decompress the supply flow path to a predetermined pressure value, and then opens the supply valve to open the check valve.

10. The inkjet printing apparatus according to claim 1 , wherein the tank is a sub-tank storing the ink supplied from a main tank attachable to and detachable from the inkjet printing apparatus.

11. The inkjet printing apparatus according to claim 1 , wherein the print head is a line head in which the ejection openings corresponding to a width of a print medium are arrayed on the ejection opening surface.

12. The inkjet printing apparatus according to claim 1 , wherein the control unit controls to drive the tank decompression pump and the supply pump simultaneously to fill the collection flow path with the ink on arrival of the printing apparatus.

13. The inkjet printing apparatus according to claim 1 , wherein the control unit controls to drive the tank decompression pump and the supply pump simultaneously to fill the collection flow path with the ink after the ink has been entirely collected to the tank.

14. A control method of an inkjet printing apparatus, wherein the apparatus comprises:
a print head having an ejection opening surface on which ejection openings for ejecting ink are formed;
a tank storing ink to be supplied to the print head;
a supply flow path for supplying the ink from the tank to the print head;
a collection flow path for collecting the ink from the print head to the tank; and
a cap configured to cover the ejection opening surface;
wherein the control method comprises the steps of:
covering the ejection opening surface with the cap;
driving a supply pump so as to fill the supply flow path and the print head with the ink;
separating the ejection opening surface and the cap when the print head is filled with the ink; and
driving the supply pump and the tank decompression pump simultaneously so as to fill the collection flow path with the ink.

15. The control method of the inkjet printing apparatus according to claim 14 , further comprising the step of:
driving the supply pump and the tank decompression pump simultaneously when the cap is separated from the ejection opening surface.

16. The control method of the inkjet printing apparatus according to claim 14 , the apparatus further comprising a cap constructed to a cap decompression pump connected to the cap and constructed to decompress the inside of the cap,
the method further comprising the step of:
driving the supply pump and the cap decompression pump with the ejection opening surface covered with the cap to fill the print head with the ink before the start of ink filling operation of the collection flow path.

17. The control method of the inkjet printing apparatus according to claim 16 , wherein driving the cap decompression pump communicates a flow path from the tank to the ejection openings.

18. The control method of the inkjet printing apparatus according to claim 16 , wherein the tank decompression pump is a common pump that also functions as the cap decompression pump.

19. The control method of the inkjet printing apparatus according to claim 18 , the apparatus further comprising:
a first valve provided in a flow path connecting the cap decompression pump to the cap; and
a second valve provided in a flow path connecting the cap decompression pump to the tank,
wherein the cap decompression pump is connected to the tank, and
the method further comprising the step of:
closing the first valve and open the second valve to fill the collection flow path with the ink after

Assignees

• Canon Kk

Inventors

• Tokisawa Toshiaki
• Mukoyama Yumi
• Okude Kyoshiro
• Abe Takashi
• Kiuchi Takahiro

Classifications

• B41J2/16508

  connected with the printer frame · CPC title

• B41J2/18 Primary

  Ink recirculation systems · CPC title

• B41J2/245

  line printer type (B41J2/25, B41J2/265 take precedence) · CPC title

• B41J2002/17579

  Measuring electrical impedance for ink level indication · CPC title

• B41J2/17566

  Ink level or ink residue control · CPC title