# US 11,077,670 B2 · Inkjet printing apparatus and ink filling method

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- Number: US 11,077,670 B2
- Document ID: US11077670B2
- Status: Granted
- Kind: B2
- Application number: 16/254,505
- Filed: 2019-01-22
- Published: 2019-08-01
- Granted: 2021-08-03
- Earliest claimed: 2018-01-30
- Assignees: Canon Kabushiki Kaisha
- Applicants: Canon Kabushiki Kaisha
- Inventors: Toshimitsu Danzuka; Naoaki Wada; Kazuki Narumi; Tomoki Yamamuro; Hiroshi Taira; Akiko Aichi; Noboru Kunimine; Taku Yokozawa; Kazuo Suzuki; Kazuhiko Sato; Masataka Kato; Shin Genta; Hiroto Kango
- Web page: https://patentgrep.com/patent/US11077670B2

## CPC

- B41J 2/17566: {Ink level or ink residue control}
- B41J 2/16508: {connected with the printer frame}
- B41J 2/16532: {by applying vacuum only}
- B41J 2/175: Ink supply systems {; Circuit parts therefor}
- B41J 2/17596: {Ink pumps, ink valves}
- B41J 2/19: for removing air bubbles
- B41J 29/38: Drives, motors, controls or automatic cut-off devices for the entire printing mechanism
- B41J 2/16523: {Waste ink transport from caps or spittoons, e.g. by suction (Collecting or collectors of waste ink B41J2/1721)}
- B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS

## Abstract

According to an embodiment of this invention, an apparatus comprises: a detachable inktank containing ink; a subtank containing the ink supplied from the inktank; a printhead configured to discharge the ink supplied from the subtank; an ink supply path connecting the subtank to the printhead; a valve arranged on the ink supply path; a supply unit configured to supply the ink from the inktank to the subtank by repeatedly opening and closing the valve; a suction unit configured to suck the ink from the printhead; and a control unit configured to control, when the inktank is attached, the supply unit to operate for a predetermined number of times to supply the ink from the inktank to the subtank, and to subsequently control the suction unit to operate to supply the ink from the subtank to the printhead.

## Claims

### Claim 1

An inkjet printing apparatus comprising:
a detachable inktank which contains ink;
a subtank which contains the ink supplied from the inktank;
a printhead configured to discharge the ink supplied from the subtank;
an ink supply path which connects the subtank to the printhead;
a supply unit configured to supply the ink from the inktank to the subtank;
a suction unit configured to suck the ink from the printhead by driving a suction pump;
a detection unit configured to detect whether an amount of ink contained in the subtank is larger than a predetermined amount; and
a control unit configured to control, after the inktank is attached, the supply unit to supply the ink from the inktank to the subtank until the detection unit detects that the amount of ink contained in the subtank is larger than the predetermined amount, and to subsequently control the suction unit to operate to supply the ink from the subtank to the printhead via the ink supply path.

### Claim 2 (depends on 1)

The apparatus according to claim 1, wherein the supply unit includes a valve, whose capacity is variable, being arranged on the ink supply path.

### Claim 3 (depends on 2)

The apparatus according to claim 2, wherein the supply unit changes the valve from an open state to a closed state to cause air in the subtank to flow out to the inktank and changes the valve from the closed state to the open state to cause the ink in the inktank to flow into the subtank.

### Claim 4 (depends on 2)

The apparatus according to claim 2, wherein the suction unit further includes:
a cap that covers an orifice surface of the printhead,
wherein the suction pump is configured to suck an interior of the cap in a state in which the orifice surface is covered by the cap.

### Claim 5 (depends on 4)

The apparatus according to claim 4, wherein the suction unit drives the suction pump when the valve is in a closed state, and subsequently switches the valve to an open state to cause the ink to move from the subtank to the printhead.

### Claim 6 (depends on 5)

The apparatus according to claim 5, wherein the control unit opens an air communication valve arranged on the cap after causing the suction unit to perform a suction operation for a predetermined number of times, and further causes the suction unit to perform the suction operation.

### Claim 7

An ink filling method of an inkjet printing apparatus that includes a detachable inktank which contains ink, a subtank which contains the ink supplied from the inktank, a printhead configured to discharge the ink supplied from the subtank, an ink supply path which connects the subtank to the printhead, and a detection unit configured to detect whether an amount of ink contained in the subtank is larger than a predetermined amount, the method comprising:
performing, after the inktank is attached, first ink filling of supplying the ink from the inktank to the subtank until the detection unit detects that the amount of ink contained in the subtank is larger than the predetermined amount; and
performing, after the first ink filling, second ink filling of supplying the ink from the subtank to the printhead via the ink supply path by sucking the ink from the printhead by driving a suction pump.

### Claim 8

An inkjet printing apparatus comprising:
a detachable inktank which contains ink;
a subtank which contains the ink supplied from the inktank;
a printhead configured to discharge the ink supplied from the subtank;
an ink supply path which connects the subtank to the printhead;
a supply unit configured to include a valve, whose volume is variable, being arranged on the ink supply path, and configured to supply the ink from the inktank to the subtank by varying the volume of the valve;
a suction unit configured to perform a suction operation of sucking the ink from the printhead by driving a suction pump;
a first detection unit configured to detect whether an amount of the ink contained in the inktank is or is not less than a first threshold value;
a second detection unit configured to detect whether an amount of the ink contained in the subtank is or is not less than a second threshold value; and
a control unit configured to control the suction unit to perform the suction operation in a case in which the first detection unit detects that the amount of ink contained in the inktank is less than the first threshold value and the second detection unit detects that the amount of ink contained in the subtank is not less than the second threshold value.

### Claim 9 (depends on 8)

The apparatus according to claim 8, wherein
in a case in which the first detection unit detects that the amount of ink contained in the inktank is less than the first threshold value and the second detection unit detects that the amount of ink contained in the subtank is less than the second threshold value, the control unit prompts a user to exchange the attached inktank.

### Claim 10 (depends on 9)

The apparatus according to claim 9, further comprising:
a display unit configured to display a message to prompt the user to exchange the inktank.

### Claim 11 (depends on 10)

The apparatus according to claim 10, wherein in a case where the inktank has been exchanged in response to the displayed message, the control unit sets the display of the message displayed by the display unit to OFF.

### Claim 12 (depends on 8)

The apparatus according to claim 8, wherein the supply unit varies the volume of the valve by opening and closing the valve.

### Claim 13 (depends on 12)

The apparatus according to claim 12, wherein the supply unit changes the valve from an open state to a closed state to cause air in the subtank to flow out to the inktank and changes the valve from the closed state to the open state to cause the ink in the inktank to flow into the subtank.

### Claim 14 (depends on 13)

The apparatus according to claim 13, wherein the suction unit includes:
a cap that covers an orifice surface of the printhead,
wherein the suction pump is configured to suck an interior of the cap in a state in which the orifice surface is covered by the cap.

### Claim 15 (depends on 8)

The apparatus according to claim 8, wherein
the second threshold value is an approximately maximum amount of ink containable in the subtank.