Printing device and printing method for discharging ink from nozzle row including nozzle groups

Patent metadata

Field	Value
Publication number	US-9498955-B2
Application number	US-201514704305-A
Country	US
Kind code	B2
Filing date	May 5, 2015
Priority date	May 30, 2014
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

A printing device includes a printing head and a control unit. The printing head has a nozzle row with a one end side nozzle group of nozzles of one end side of the nozzle row, an other end side nozzle group of nozzles of an other end side of the nozzle row, and a center nozzle group of nozzles of the nozzle row, which does not correspond to the one and other end side nozzle groups. The control unit is configured to discharge the ink on a designated area on a print medium from the nozzles included in the center nozzle group and the other end side nozzle group with a first movement of the printing head and discharge the ink on the designated area from the nozzles included in the center nozzle group and the one end side nozzle group with a second movement next to the first movement.

First claim

What is claimed is:

1. A printing device comprising
a printing head having a nozzle row on which are formed a plurality of nozzles aligned in a first direction and configured to discharge ink, the nozzle row including a one end side nozzle group which is a plurality of nozzles of one end side of the nozzle row, an other end side nozzle group which is a plurality of nozzles of an other end side of the nozzle row, and a center nozzle group which is a plurality of nozzles of the nozzle row and does not correspond to the one end side nozzle group and the other end side nozzle group;
a control unit configured to convey a print medium in the first direction, configured to move the printing head in a second direction that intersects the first direction, and configured to perform printing by discharging the ink from the nozzles onto the print medium during movement of the printing head; and
an ink volume determining unit configured to, by referencing a color conversion table for converting a color system used by image data that expresses an image to a color system of the ink discharged by the printing head, determine an ink volume within a designated upper limit value for each pixel of the image data,
the control unit being configured to, during a first movement which is the movement, discharge the ink on a designated area on the print medium from the nozzles included in the center nozzle group and the other end side nozzle group while the control unit is configured not to discharge the ink on the designated area from the nozzles included in the one end side nozzle group, and
configured to, during a second movement which is the movement the next time after the first movement, discharge the ink on the designated area from the nozzles included in the center nozzle group and the one end side nozzle group while the control unit is configured not to discharge the ink on the designated area from the nozzles included in the other end side nozzle group,
the control unit being configured to control discharging of the ink by the nozzles by allocating to the nozzles pixels for which discharge or non-discharge of the ink has been determined based on the ink volume,
when the ink volume determining unit, among a pre-defined first color conversion table using a first upper limit value for the upper limit value, and a pre-defined second color conversion table using a second upper limit value higher than the first upper limit value for the upper limit value, references the pre-defined second color conversion table to determine the ink volume, the control unit being configured to allocate pixels to the nozzles included in the center nozzle group and the other end side nozzle group in correspondence to the first movement, and allocate pixels to the nozzles included in the center nozzle group and the one end side nozzle group in correspondence to the second movement, and
when the ink volume determining unit references the first color conversion table to determine the ink volume, the control unit being configured to allocate pixels to the nozzles included in the one end side nozzle group, the center nozzle group, and the other end side nozzle group respectively in correspondence to each time of the movement.

2. The printing device according to claim 1 , wherein
the control unit is configured to print a raster line expressed by ink droplets being aligned in the second direction by discharging the ink from the nozzles during one time of the movement.

3. The printing device according to claim 1 , wherein
a ratio of a nozzle count of the center nozzle group and the other end side nozzle group relative to a nozzle count of the nozzle row is 3/5 or greater and 3/4 or less, and a ratio of a nozzle count of the center nozzle group and the one end side nozzle group relative to the nozzle count of the nozzle row is 3/5 or greater and 3/4 or less.

4. A printing device configured to convey a print medium in a first direction, configured to move a printing head, which has nozzle row on which are formed a plurality of nozzles aligned in the first direction and configured to discharge ink, in a second direction that intersects the first direction, and configured to perform printing by discharging the ink from the nozzles onto the print medium during movement of the printing head,
the nozzle row being constituted such that the nozzle row is segmented into a plurality of segments along the first direction, and a color of the ink discharged by the nozzles is differentiated for each of the segments,
the printing device comprising:
a discharge control unit configured to
during a first movement which is the movement, among a one end side nozzle group using a plurality of nozzles of one end side of the nozzle row of each of the segments, an other end side nozzle group using a plurality of nozzles of an other end side of the nozzle row of each of the segments, and a center nozzle group using a plurality of nozzles of the nozzle row that do not correspond to the one end side nozzle group and the other end side nozzle group of each of the segments, discharge the ink on a designated area on the print medium from the nozzles included in the center nozzle group and the other end side nozzle group of each of the segments without discharging the ink on the designated area from the nozzles included in the one end side nozzle group of each of the segments, and
during a second movement which is the movement the next time after the first movement, discharge the ink to the designated area from the nozzles included in the center nozzle group and the one end side nozzle group of each of the segments without discharging the ink on the designated area from the nozzles included in the other end side nozzle group of each of the segments; and

an ink volume determining unit configured to, by referencing a color conversion table for converting a color system used by image data that expresses an image to a color system of the ink discharged by the printing head, determine an ink volume within a designated upper limit value for each pixel of the image data,
the discharge control unit being configured to control discharging of the ink by the nozzles by allocating to the nozzles pixels for which discharge or non-discharge of the ink has been determined based on the ink volume,
when the ink volume determining unit, among a pre-defined first color conversion table using a first upper limit value for the upper limit value, and a pre-defined second color conversion table using a second upper limit value higher than the first upper limit value for the upper limit value, references the pre-defined second color conversion table to determine the ink volume, the discharge control unit being configured to allocate pixels to the nozzles included in the center nozzle group and the other end side nozzle group in correspondence to the first movement, and allocate pixels to the nozzles included in the center nozzle group and the one end side nozzle group in correspondence to the second movement, and
when the ink volume determining unit references the first color conversion table to determine the ink volume, the discharge control unit being configured to allocate pixels to the nozzles included in the one end side nozzle group, the center nozzle group, and the other end side nozzle group respectively in correspondence to each time of the movement.

5. The printing device according to claim 4 , wherein
the nozzle row is divided into a segment for which the nozzles discharge cyan ink, a segment for which the nozzles discharge magenta ink, and a segment for which the nozzles discharge yellow ink.

6. The printing device according to claim 1 , wherein
pigment ink is used as the ink.

7. The printing device according to claim 1 , wherein
the printing head is con

Assignees

• Seiko Epson Corp

Inventors

• Kobayashi Takashi

Classifications

• G06K15/107

  Mask selection · CPC title

• B41J2/04543 Primary

  Block driving · CPC title

• B41J2/145 Primary

  Arrangement thereof · CPC title

• B41J2/04535

  involving calculation of drop size, weight or volume · CPC title

• B41J2/2103

  Features not dealing with the colouring process per se, e.g. construction of printers or heads, driving circuit adaptations · CPC title