Ink cartridge and ink jet printing apparatus

Patent metadata

Field	Value
Publication number	US-9375938-B2
Application number	US-201514744939-A
Country	US
Kind code	B2
Filing date	Jun 19, 2015
Priority date	Jun 27, 2014
Publication date	Jun 28, 2016
Grant date	Jun 28, 2016

Abstract

The ink cartridge has a communication unit for allowing an ink storage chamber to communicate with a space outside a housing. The communication unit includes a communication port formed on an outside surface of the housing, a merging channel having an end which communicates with the communication port, and a plurality of branch channels, each having an end which communicates with the merging channel and the other end which communicates with the ink storage chamber. In the branch channel, while ink flows backward, the ink flowing from the merging channel branches into the first branch channel and the second branch channel. At the same time, a ratio (Q 1 /Q 2 ) between an ink flow rate in the first branch channel and an ink flow rate in the second branch channel while the ink is supplied is smaller than that while the ink flows backward.

First claim

What is claimed is:

1. An ink cartridge comprising:
a housing in which an ink storage chamber for storing ink is formed; and
a communication unit configured to allow the ink storage chamber to communicate with a space outside the housing, wherein the communication unit includes a communication port formed on an outside surface of the housing, a merging channel having an end which communicates with the communication port, and a branch channel having an end which communicates with the merging channel and the other end which communicates with the ink storage chamber,
wherein the branch channel includes at least one first branch channel communicating with a lower layer area in the ink storage chamber and at least one second branch channel communicating with an upper layer area located higher than the lower layer area in a gravity direction,
wherein while ink is supplied to flow from the ink storage chamber to the outside, the ink flowing from the first branch channel and the second branch channel merges into the merging channel, and
wherein in a case where an ink flow rate in the first branch channel is represented by Q 1 and an ink flow rate in the second branch channel is represented by Q 2 , a ratio (Q 1 /Q 2 ) between the ink flow rate in the first branch channel and the ink flow rate in the second branch channel while the ink is supplied is smaller than that while the ink flows backward to flow from the outside to the ink storage chamber.

2. The ink cartridge according to claim 1 , wherein the lower layer area in the ink storage chamber includes ink having a higher concentration of a colorant than that of ink in the upper layer area due to precipitation of the colorant in the ink.

3. The ink cartridge according to claim 1 , wherein while the ink is supplied, after flowing into the merging channel, a high concentration ink flowing from the lower layer area to the first branch channel and a low concentration ink flowing from the upper layer area to the second branch channel are supplied from the communication port to the outside of the housing.

4. The ink cartridge according to claim 1 , wherein an angle defined by a center axis of the merging channel and a center axis of the first branch channel is greater than an angle defined by the center axis of the merging channel and a center axis of the second branch channel.

5. The ink cartridge according to claim 4 , wherein an angle defined by the center axis of the merging channel and the center axis of the first branch channel is within a range of 170 degrees to 190 degrees.

6. The ink cartridge according to claim 5 , wherein an angle defined by the center axis of the merging channel and the center axis of the second branch channel is within a range of 80 degrees to 100 degrees.

7. The ink cartridge according to claim 1 , wherein the housing has a decompression port that can be connected to a decompression unit for decompressing the ink storage chamber.

8. The ink cartridge according to claim 1 , wherein the communication port can be connected to an ink delivery unit for supplying ink to a print head that can eject ink.

9. The ink cartridge according to claim 1 , wherein a channel communicating with the lower layer area is configured such that a width in a direction perpendicular to a gravity direction is greater than a width in the gravity direction.

10. An ink jet printing apparatus for supplying ink from an ink delivery unit to a print head and performing printing on a print medium by ejecting ink from the print head,
the ink delivery unit comprising:
an ink cartridge for storing ink to be supplied to a print head;
an ink delivery unit capable of delivering ink between the ink cartridge and the print head; and
an ink backflow unit configured to cause ink to flow backward from the ink delivery unit to the ink cartridge,
the ink cartridge comprising:
a housing in which an ink storage chamber for storing ink is formed; and
a communication unit for allowing the ink delivery unit to communicate with the ink storage chamber,
the communication unit including a communication port formed on an outside surface of the housing, a merging channel having an end which communicates with the communication port, and branch channels, each having an end which communicates with the merging channel and the other end which communicates with the ink storage chamber,
wherein each of the branch channels includes at least one first branch channel communicating with a lower layer area in the ink storage chamber and at least one second branch channel communicating with an upper layer area located higher than the lower layer area in a gravity direction in the ink storage chamber,
wherein while ink is supplied to flow from the ink storage chamber to the outside, the ink flowing from the first branch channel and the second branch channel merges into the merging channel, and
wherein in a case where an ink flow rate in the first branch channel is represented by Q 1 and an ink flow rate in the second branch channel is represented by Q 2 , a ratio (Q 1 /Q 2 ) between the ink flow rate in the first branch channel and the ink flow rate in the second branch channel while the ink is supplied is smaller than that while the ink flows backward to flow from the outside to the ink storage chamber.

11. The ink jet printing apparatus according to claim 10 , wherein the ink backflow unit increases a pressure in the ink delivery unit to be higher than a pressure in the ink storage chamber, so that ink flows backward from the ink delivery unit to the ink storage chamber.

12. The ink jet printing apparatus according to claim 10 , wherein the ink cartridge has a storage unit configured to store information for determining an operation of the ink backflow unit.

13. The ink jet printing apparatus according to claim 12 , wherein the ink backflow unit determines an operation of the ink backflow unit based on at least one piece of information stored in the storage unit, the information including an ink filling time, a type of ink, a last date on which ink backflow was performed, an amount of ink filled, and a remaining amount of ink.

14. The ink jet printing apparatus according to claim 10 , wherein the ink delivery unit includes a plurality of the ink cartridges, and the ink backflow unit causes ink to flow backward from the ink delivery unit to the ink storage chamber with respect to all of the plurality of ink cartridges through the same process.

15. The ink jet printing apparatus according to claim 14 , wherein in a case where there is at least one ink cartridge requiring backflow of ink among the plurality of ink cartridges, the ink backflow unit causes the ink to flow backward with respect to all of the plurality of ink cartridges.

Assignees

• Canon Kk

Inventors

• Kondo Soji
• Kotaki Yasuo
• Udagawa Kenta
• Nabeshima Naozumi
• Nanjo Tatsuo
• Yoshii Kazuya

Classifications

• B41J2/1752 Primary

  Mounting within the printer · CPC title

• B41J2/17513

  Inner structure · CPC title

• B41J2/17509

  Whilst mounted in the printer · CPC title

• B41J2/17553

  Outer structure · CPC title