Printing apparatus and method of controlling printing apparatus

Patent metadata

Field	Value
Publication number	US-12434486-B2
Application number	US-202218067946-A
Country	US
Kind code	B2
Filing date	Dec 19, 2022
Priority date	Dec 27, 2021
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

An object is to provide a technique of calculating an ejection amount of an ink in accordance with a printing head. A printing apparatus includes: a printing head including an ejection port array in which multiple ejection ports to eject an ink are arrayed; a conveyer unit configured to convey a printing medium in a conveyance direction; and a controller unit configured to control the printing head. The controller unit executes processing to obtain the printing dot number based on printing data and processing to calculate an amount of the ink used in a case of performing printing based on the printing data by using different calculation methods between a case where a first printing mode is set and a case where a second printing mode is set based on the printing dot number and an ejection amount conversion factor corresponding to a temperature of the printing head.

First claim

What is claimed is:

1. A printing apparatus comprising:
a printing head including an ejection port array in which a plurality of ejection ports to eject an ink are arrayed;
a conveyer unit configured to convey a printing medium in a conveyance direction;
a controller unit configured to count a printing dot number based on printing data, perform a first calculation for calculating an amount of the ink used in a case of performing printing based on the printing data in a case where a first printing mode is set based on the printing dot number, and perform a second calculation different from the first calculation for calculating an amount of the ink used in a case of performing printing based on the printing data in case where a second printing mode is set,
wherein the controller unit is configured to (1) in a case where the first printing mode is set, refer to a first region greater than a second region of an ejection surface provided with the plurality of ejection ports as a unit of the first calculation, and (2) in a case where the second printing mode is set, refer to the second region smaller than the first region as a unit of the second calculation.

2. The printing apparatus according to claim 1 , wherein a difference between the first printing mode and the second printing mode is a conveyance speed or a conveyance amount of the conveyer unit.

3. The printing apparatus according to claim 1 , wherein a conveyance speed of the conveyer unit in a printing operation in the first printing mode is faster than a conveyance speed of the conveyer unit in a printing operation in the second printing mode.

4. The printing apparatus according to claim 1 , wherein a conveyance amount of the conveyer unit in a printing operation in the first printing mode is greater than a conveyance amount of the conveyer unit in a printing operation in the second printing mode.

5. The printing apparatus according to claim 1 , further comprising:
a movement unit configured to move the printing head in a scanning direction crossing a direction in which the plurality of ejection ports are arrayed,
wherein a number of passes in a case of printing an image in the second printing mode is greater than a number of passes in a case of printing an image in the first printing mode, and
wherein the printing head prints an image with a plurality of times of passes on a predetermined region including a plurality of unit regions on the printing medium.

6. The printing apparatus according to claim 1 , wherein each of the first calculation and the second calculation is a method of multiplying the dot number to be printed by an ejection amount conversion factor corresponding to the temperature of the printing head.

7. The printing apparatus according to claim 6 , wherein the ejection amount conversion factor used in a case where the temperature of the printing head is a first temperature.

8. The printing apparatus according to claim 1 , further comprising:
a temperature sensor configured to detect the temperature of the printing head,
wherein the controller unit performs the first calculation and the second calculation by using the temperature of the printing head detected by the temperature sensor.

9. The printing apparatus according to claim 1 , wherein the controller unit is configured to, in a case where the first printing mode is set, calculate an average value of the dot numbers to be printed between the plurality of adjacent ejection ports as the first calculation and calculate an amount of an ink droplet used for the printing assuming that the average value is a value of the dot number to be printed.

10. The printing apparatus according to claim 1 , wherein the first printing mode is a printing mode using a flat mask configured such that the ejection frequencies of ink droplets ejected by the plurality of ejection ports are equal to each other.

11. The printing apparatus according to claim 1 , wherein the controller unit is configured to, in a case where the second printing mode is set, calculate the dot number to be printed corresponding to each of the plurality of ejection ports, multiplies the dot number by the ejection amount conversion factor in accordance with each of the plurality of ejection ports, and calculate the amount of the ink droplet used for the printing by accumulating ejection amounts of the plurality of ejection ports.

12. The printing apparatus according to claim 1 , wherein the second printing mode is a printing mode using a mask configured such that ejection frequencies of ejection ports provided in a center portion in an ejection port group including the plurality of ejection ports are high and ejection frequencies of ejection ports provided on sides of end portions in the ejection port group are low.

13. The printing apparatus according to claim 12 , wherein the controller unit is configured to, in a case where a shape of a mask such that the ejection frequencies are low is illustrated by using a graph, (1) calculate an average value of the dot numbers to be printed between the plurality of adjacent ejection ports in a case where a slope of the graph does not exceed a predetermined value as the second calculation, and (2) calculate the amount of the ink droplet used for the printing assuming that the average value is a value of the dot number to be printed.

14. The printing apparatus according to claim 1 , wherein the controller unit is configured to, in a case where a shape of a mask configured such that ejection frequencies vary across the plurality of ejection ports is illustrated by using a graph, (1) calculate an average value of the dot numbers to be printed between the plurality of adjacent ejection ports in a case where a slope of the graph does not exceed a predetermined value as the second calculation, and (2) calculate the amount of the ink droplet used for the printing assuming that the average value is a value of the dot number to be printed.

15. A printing apparatus comprising:
a printing head including a first ejection port array in which first ejection ports to eject an ink droplet of a predetermined color are arrayed and a second ejection port array in which second ejection ports to eject an ink droplet of a color of lower density than the predetermined color are arrayed;
a conveyer unit configured to convey a printing medium in a conveyance direction; and
a controller unit configured to store printing data of at least one scanning in a printing buffer, count a dot number in the first ejection ports and a dot number in the second ejection ports based on the printing data, and calculate a use amount of the ink droplet of the predetermined color and a use amount of the ink droplet of the color of lower density than the predetermined color in a case of performing printing based on the printing data by using different methods between a case where the ink droplet of the predetermined color is ejected and a case where the ink droplet of the color of lower density than the predetermined color is ejected based on the dot number in the first ejection ports and the dot number in the second ejection ports and an ejection amount conversion factor corresponding to a temperature of the printing head.

16. The printing apparatus according to claim 15 , further comprising:
a movement unit configured to move the printing head in a scanning direction crossing a direction in which plurality of ejection ports are arrayed,
wherein the printing head prints an image with a plurality times of passes on a predetermined region including a plurality of unit regions on a printing medium.

17. The pr

Assignees

• Canon Kk

Inventors

• Yamamuro Tomoki
• Sato Kazuhiko
• Suzuki Kazuo
• Murase Takeshi
• Taira Hiroshi
• Kawafuji Hiroshi
• Mogi Sae
• Nitta Masaki

Classifications

• B41J2/2132 Primary

  Print quality control characterised by dot disposition, e.g. for reducing white stripes or banding (methods for local corrections by dot omission, image edge enhancement, or multi-pass mask selection G06K15/102; colour conversion H04N1/40) · CPC title

• B41J2/04563

  detecting head temperature; Ink temperature · CPC title

• B41J2/2107 Primary

  characterised by the ink properties (supplying ink in a solid state B41J2/17593) · CPC title