JP2002172772A - Method for printing up to end of print medium without staining platen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To print up to the end of a print sheet without staining a platen with ink drops. SOLUTION: The platen 26 of the printer comprises an upstream side supporting part 26sf, an upstream side groove 26f, a central supporting part 26c and a downstream side groove 26r disposed sequentially from the upstream in the sub-scanning direction. The printer performs printing at the upper end of a print sheet using only a fourth nozzle group Nr facing the downstream side groove 26r, and performs printing at the lower end of the print sheet using only a second nozzle group Nh facing the upstream side groove 26f. Between printing of the upper end and the intermediate part, upper end shift processing is performed in the same sub-scanning feed as the upper end where printing is performed using all nozzle groups similarly to the intermediate part. Between printing of the intermediate part and the lower end, lower end shift processing is performed in the same sub-scanning feed as the lower end where printing is performed using nozzle groups Nh, Ni and Nr. Since the shift processing is performed, upper end processing, intermediate processing and lower end processing can be carried out smoothly without requiring reverse feed of sub-scanning.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for recording dots on the surface of a recording medium using a dot recording head, and more particularly to a technique for printing up to the end of a printing sheet without soiling a platen.

[0002]

2. Description of the Related Art In recent years, as an output device of a computer,
2. Description of the Related Art Printers that eject ink from nozzles of a print head are widely used. FIG. 27 is a side view showing the periphery of a print head of a conventional printer. The printing paper P is supported on the platen 26o so as to face the head 28o. The printing paper P is supplied to the upstream paper feed rollers 25p and 25q arranged upstream of the platen 26o and the downstream paper feed rollers 25r and 25r arranged downstream of the platen 26.
It is sent in the direction of arrow A by 25s. When ink is ejected from the head, dots are sequentially recorded on the printing paper P, and an image is printed.

[0003]

When an image is to be printed to the edge of the printing paper in the above-described printer,
It is necessary to arrange the printing paper so that the edge of the printing paper is located below the printing head, that is, on the platen, and eject ink droplets from the printing head. However, in such printing, due to an error in the feeding of the printing paper or a shift in the landing position of the ink droplet, the ink droplet may deviate from the end of the printing paper where it should originally land and land on the platen. . In such a case, the printing paper that subsequently passes on the platen is stained by the ink that has landed on the platen.

The present invention has been made to solve the above-mentioned problems in the prior art, and has as its object to provide a technique for performing printing up to the end of a printing sheet without causing ink drops to land on a platen. I do.

[0005]

In order to solve at least a part of the above problems, the present invention provides a dot forming element group including a plurality of dot forming elements for ejecting ink droplets. A predetermined process is performed for a dot recording apparatus that records dots on the surface of a print medium using a dot recording head. This dot recording apparatus drives a dot recording head and at least one of a print medium to perform main scanning, and drives at least a part of a plurality of dot forming elements during the main scanning. A head driving unit for forming dots and a plurality of dot forming elements are provided to extend in the main scanning direction so as to face a plurality of dot forming elements in at least a part of the main scanning path, so that the print medium faces the dot recording head. A sub-scanning drive unit that performs sub-scanning by driving the print medium in a direction intersecting with the main scanning direction during the main scanning, and a control unit that controls each unit.

The platen of the dot recording apparatus is provided at a position facing a first partial dot forming element group composed of a part of the plurality of dot forming elements in the main scanning direction, and is provided with a printing medium. A first supporting portion for supporting the second partial dot forming element group provided downstream of the first partial dot forming element group in the sub-scanning direction from the first partial dot forming element group among the plurality of dot forming elements. A first groove portion extending in the scanning direction, and a third partial dot forming element group provided downstream of the second partial dot forming element group in the sub-scanning direction among the plurality of dot forming elements. A second support portion that extends in the main scanning direction at a position facing the main scanning direction and supports the print medium; and a downstream side in the sub scanning direction from the third partial dot forming element group among the plurality of dot forming elements. Established in Fourth, partial dot forming element group and facing the position of, and has a second groove portion provided to extend in the direction of the main scan to be.

In such a dot recording apparatus, the following printing is performed. Here, the surface portion of the print medium is divided into an upper end portion including an upper end, an upper end transition portion, an intermediate portion, a lower end transition portion, and a lower end portion including a lower end in order from the top. The printing means that, first, using the fourth partial dot forming element group without using the first to third partial dot forming element groups, a dot is formed at the upper end in the first sub-scanning mode. Form. Then, using the first to fourth partial dot forming element groups, a dot is formed at the upper end transition portion in the first sub-scanning mode. Thereafter, by using the first to fourth partial dot forming element groups, in the second sub-scanning mode, the maximum sub-scanning feed amount is larger than the maximum sub-scanning feed amount in the first sub-scanning mode. A dot is formed in the middle part.

[0008] According to this aspect, dots can be formed at the upper end portion up to the end of the print medium without soiling the platen. Then, the reverse scanning of the sub-scan is performed from the dot formation at the upper end portion using the fourth partial dot forming element group to the dot formation at the intermediate portion using the first to fourth partial dot forming element groups. The transition can be smooth.

When forming dots at the upper end, the dots are formed when the print medium is supported by the platen and the upper end of the print medium is above the opening of the second groove. Can be. With such an embodiment, dots can be formed at the upper end of the print medium without blanks by using the fourth partial dot forming element group.

After the dot formation in the intermediate portion, it is preferable to further perform the following printing. That is, without using the first partial dot forming element group, the second to fourth partial dot forming element groups are used, and the maximum feed amount of the sub-scan is increased in the sub-scan in the second sub-scan mode. In the third sub-scanning mode smaller than the maximum feed amount, a dot is formed at the lower end transition portion. Then, a dot is formed at the lower end in the third sub-scanning mode using the second partial dot forming element group without using the first, third, and fourth partial dot forming element groups. .

According to this aspect, it is possible to form dots at the lower end to the edge of the print medium without soiling the platen. Then, from the dot formation in the intermediate portion using the first to fourth partial dot formation element groups,
It is possible to smoothly shift to dot formation at the lower end portion using the second partial dot formation element group without performing reverse feed in the sub-scan.

It is preferable that the nozzles of the second partial dot forming element group have smaller average deviation amounts of the dot forming positions on the print medium than the nozzles of the first partial dot forming element group. With such an embodiment, high-quality printing can be performed in the printing of the lower end portion using only the nozzles of the second partial dot forming element group.

When forming dots at the lower end, the dots are formed when the print medium is supported by the platen and the lower end of the print medium is above the opening of the first groove. Can be. With such an embodiment, dots can be formed at the lower end of the print medium without blanks by using the second partial dot forming element group.

The platen is mainly located at a position facing the fifth partial dot forming element group provided downstream of the fourth partial dot forming element group in the sub-scanning direction among the plurality of dot forming elements. In the case where a third support portion provided to extend in the scanning direction and support the print medium is provided, it is preferable to perform the following printing.

First, the first, second, third, and fifth partial dot forming element groups are not used, but the fourth partial dot forming element group is used. A dot is formed in the portion. Then, using the first to fourth partial dot forming element groups, a dot is formed at the upper end transition portion in the first sub-scanning mode. Thereafter, by using the first to fifth partial dot forming element groups, in the second sub-scanning mode in which the maximum sub-scanning feed amount is larger than the maximum sub-scanning feed amount in the first sub-scanning mode. A dot is formed in the middle part.

According to this aspect, it is possible to form dots at the upper end to the edge of the print medium without soiling the platen. Then, the reverse scanning of the sub-scan is not performed from the dot formation at the upper end using the fourth partial dot forming element group to the dot formation at the intermediate part using the first to fifth partial dot forming element groups. The transition can be smooth.

It is preferable that the nozzles of the fourth partial dot forming element group have a smaller average deviation amount of the dot forming positions on the print medium than the nozzles of the fifth partial dot forming element group. With such an embodiment, high-quality printing can be performed in the printing of the lower end portion using only the nozzles of the fourth partial dot forming element group.

Further, after the dot formation in the intermediate portion, it is preferable to further perform the following printing. That is, without using the first partial dot forming element group, the second to fifth partial dot forming element groups are used, and the maximum feed amount of the sub-scan is increased in the sub-scan in the second sub-scan mode. In the third sub-scanning mode smaller than the maximum feed amount, a dot is formed at the lower end transition portion. Then, without using the first, third, fourth, and fifth partial dot forming element groups, the second sub-dot forming element group is used, and in the third sub-scanning mode, a dot is formed at the lower end. To form

According to such an embodiment, dots can be formed at the lower end to the end of the print medium without soiling the platen. Then, from the dot formation of the intermediate portion using the first to fifth partial dot formation element groups,
It is possible to smoothly shift to dot formation at the lower end portion using the second partial dot formation element group without performing reverse feed in the sub-scan.

The present invention can be implemented in various modes as described below. (1) Dot recording device, dot recording control device, printing device. (2) Dot recording method, dot recording control method, printing method. (3) Computer programs for realizing the above devices and methods. (4) A recording medium on which a computer program for realizing the above apparatus and method is recorded. (5) A data signal embodied in a carrier wave including a computer program for realizing the above apparatus and method.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in the following order based on embodiments. A. Overview of Embodiment: First embodiment: B1. Overall configuration of device: B2. Relationship between image data and printing paper: B3. Sub-scan feed during printing: Second embodiment D. Third embodiment: Modification: E1. Modification Example 1: E2. Modified example 2: E3. Modification 3:

A. Outline of Embodiment: FIG. 1 is an explanatory diagram showing changes in nozzles used on a print head 28 of an inkjet printer according to an embodiment of the present invention. In FIG. 1, the lower surface of the print head 28 is shown on the left side, and the platen 2 corresponding to each nozzle on the print head 28 is shown on the right side.
6 is shown as a side view. On the platen 26 of this printer, an upstream supporting portion 26sf, an upstream groove portion 26f, a central supporting portion 26c,
A downstream groove 26r is provided. The nozzles provided on the print head 28 facing the platen 26 include, in order from the upstream, a first nozzle group Nf facing the upstream support portion 26sf, a second nozzle group Nh facing the upstream groove portion 26f, and a center. The nozzle group is classified into a third nozzle group Ni facing the support portion 26c and a fourth nozzle group Nr facing the downstream groove portion 26r.

This printer performs printing on only the fourth nozzle group Nr facing the downstream groove 26r when the upper end of the printing paper is on the downstream groove 26r (upper end processing). When the lower end of the printing paper is located on the upstream groove 26f, printing is performed only by the second nozzle group Nh facing the upstream groove 26f (lower end processing). By doing so, the platen 2
The image can be printed without margins up to the edge of the printing paper without soiling the upper surface of the printing paper 6. In addition, the intermediate portion of the printing paper performs printing using all the nozzle groups (intermediate processing). Therefore, printing can be performed at a high speed on the intermediate portion.

Further, between the upper end processing and the intermediate processing, the same sub-scan feed as in the upper end processing is performed, and the upper end transition processing for printing using all the nozzle groups is performed as in the intermediate processing. Also,
Between the intermediate processing and the lower end processing, the same sub-scan feed as the lower end processing is performed, and the lower end transition processing for performing printing using the nozzle groups Nh, Ni, Nr is performed. That is, the nozzle group Nf is not used in the lower end shift processing. By performing these transition processes, the upper end process, the intermediate process, and the lower end process can be smoothly performed without performing the reverse feed of the sub-scan or the positioning feed which is a large feed. As a result, printing quality is improved.

B. First embodiment: B1. Apparatus Configuration: FIG. 2 is a block diagram showing the software configuration of the printing apparatus. In the computer 90, an application program 95 operates under a predetermined operating system. A video driver 91 and a printer driver 96 are incorporated in the operating system, and image data D to be transferred to the printer 22 is output from the application program 95 via these drivers. An application program 95 for retouching an image reads an image from the scanner 12 and displays the image on the CRT 21 via the video driver 91 while performing predetermined processing on the image. The data ORG supplied from the scanner 12 is read from a color original, and has three colors of red (R), green (G), and blue (B).
This is original color image data ORG composed of color components of colors.

This application program 95
When a print command is issued in response to an instruction input from the mouse 13 or the keyboard, the printer driver 96 of the computer 90 transmits the image data to the application program 9.
5 and converted into a signal that can be processed by the printer 22 (here, a multivalued signal for each color of cyan, magenta, light cyan, light magenta, yellow, and black). In the example shown in FIG. 2, the resolution conversion module 97 is provided inside the printer driver 96.
, A color correction module 98, a halftone module 99, and a rasterizer 100. Further, a color correction table LUT and a dot formation pattern table DT are also stored.

The resolution conversion module 97 serves to convert the resolution of the color image data handled by the application program 95, that is, the number of pixels per unit length into a resolution that can be handled by the printer driver 96. The image data whose resolution has been converted in this way is still RG
Since the image information is composed of the three colors B, the color correction module 98 refers to the color correction table LUT and uses the cyan (C), magenta (M), light cyan (LC), Light magenta (L
M), yellow (Y), and black (K).

The color-corrected data has a gradation value with a width of, for example, 256 gradations. The halftone module 99 executes a halftone process for expressing this gradation value in the printer 22 by forming dots in a dispersed manner. The halftone module 99 sets the dot formation pattern of each ink dot according to the gradation value of the image data by referring to the dot formation pattern table DT, and then executes the halftone processing. The image data thus processed is rearranged by the rasterizer 100 in the order of data to be transferred to the printer 22, and output as final print data PD. The print data PD includes raster data indicating the recording state of dots during each main scan and data indicating the sub-scan feed amount. In the present embodiment, the printer 22 stores the print data P
Although it only plays a role of forming ink dots according to D and does not perform image processing, it goes without saying that these processes may be performed by the printer 22.

Next, a schematic configuration of the printer 22 will be described with reference to FIG. As shown in the figure, the printer 22 includes a mechanism for transporting a sheet P by a paper feed motor 23 and a carriage 31 that is moved by a carriage motor 24 to a sliding shaft 34.
, A mechanism for driving a print head 28 mounted on a carriage 31 to eject ink and form ink dots, a paper feed motor 23, a carriage motor 24, and a print head 28. And a control circuit 40 for exchanging signals with the operation panel 32.

The mechanism for reciprocating the carriage 31 in the axial direction of the platen 26 is provided in a direction perpendicular to the direction in which the printing paper P is conveyed. And a position detection sensor 39 for detecting the origin position of the carriage 31 and the like.

The carriage 31 includes a cartridge 71 for black ink (K), cyan (C), and light cyan (L).
C), a magenta (M), light magenta (LM), and yellow (Y) ink cartridges 72 containing six color inks can be mounted. The print head 28 below the carriage 31 has a total of six ink ejection heads 61.
When the cartridge 71 for black (K) ink and the cartridge 72 for color ink are mounted on the carriage 31 from above, ink can be supplied from each ink cartridge to the ejection heads 61 to 66. Become.

FIG. 4 is an explanatory diagram showing the arrangement of the ink jet nozzles in the print head 28. These nozzles are arranged in black (K), cyan (C), light cyan (LC), magenta (M), and light magenta (L).
M) and yellow (Y), each of which is composed of six nozzle arrays that eject ink for each color, and 48 nozzles are arranged in a row at a constant nozzle pitch k. These six nozzle arrays are arranged so as to be arranged in the main scanning direction. More specifically, the corresponding nozzles of each nozzle array are arranged so as to be arranged on the same main scanning line. These nozzle arrays (nozzle arrays) correspond to “dot forming element groups” in the claims. The “nozzle pitch” is a value indicating how many rasters (that is, how many pixels) the intervals in the sub-scanning direction of the nozzles arranged on the print head are. For example, the pitch k of the nozzles arranged at intervals of three rasters is four. The “raster” is a row of pixels arranged in the main scanning direction. A "pixel" is a square grid virtually defined on a print medium (in some cases, beyond the edge of the print medium) in order to define a position where an ink droplet lands and a dot is recorded. It is. FIG. 4 schematically shows the arrangement of the nozzles, and does not reflect the dimensions of the head or the exact number of nozzles in the embodiment.

The nozzles in each nozzle array are classified into four subgroups in order from the upstream in the sub-scanning direction. This subgroup is the "partial dot forming element group" referred to in the claims. Hereinafter, the subgroups of each nozzle array are grouped in order from the upstream in the sub-scanning direction,
f, Nh, Ni, Nr. The first nozzle group Nf on the most upstream side corresponds to the "first partial dot forming element group" in the claims, and the second nozzle group Nh corresponds to the "second portion in the claims". Dot forming element group ”. The third nozzle group Ni corresponds to a “third partial dot forming element group” in the claims, and the fourth nozzle group Nr corresponds to a “fourth partial dot forming element group” in the claims. Is equivalent to Here, the partial dot forming element groups of each nozzle array are collectively handled, and are respectively referred to as nozzle groups Nf, Nh, Ni, and Nr. These nozzle groups are determined so as to correspond to components such as grooves and support portions of a platen 26 provided at a position facing the print head 28 in the main scanning. Correspondence between components such as grooves and support portions of the platen 26 and each nozzle group will be described later.

FIG. 5 is a plan view showing the periphery of the platen 26. The platen 26 is provided longer than the maximum width of the printing paper P usable in the printer 22 in the main scanning direction. And upstream of the platen 26,
Upstream paper feed rollers 25a and 25b are provided.
While the upstream paper feed roller 25a is a single drive roller, the upstream paper feed roller 25b is a plurality of small rollers that rotate freely. Downstream of the platen, downstream paper feed rollers 25c and 25d are provided. The downstream paper feed roller 25c is a plurality of rollers provided on the drive shaft, and the downstream paper feed roller 25d is a plurality of freely rotating small rollers. The downstream paper feed roller 25d is
It has teeth (portions between grooves) radially on the outer peripheral surface, and looks like a gear when viewed from the rotation axis direction.
This downstream paper feed roller 25d is a so-called “jagged roller”.
And presses the printing paper P onto the platen 26. The downstream paper feed roller 25c and the upstream paper feed roller 25a rotate synchronously so that the outer peripheral speeds are equal.

The print head 28 is composed of the upstream paper feed rollers 25a and 25b and the downstream paper feed rollers 25.
It reciprocates in the main scanning on the platen 26 sandwiched between c and 25d. The printing paper P is transferred to the upstream paper feed roller 25.
a, 25b and the downstream side paper feed rollers 25c, 25d, and a portion therebetween is supported by the upper surface of the platen 26 so as to face the nozzle row of the print head 28. Then, sub-scan feed is performed by the upstream paper feed rollers 25a and 25b and the downstream paper feed rollers 25c and 25d, and images are sequentially recorded by ink ejected from the nozzles of the print head 28.

The platen 26 is provided with an upstream groove 26f and a downstream groove 26r on the upstream side and the downstream side in the sub-scanning direction, respectively. The upstream groove 26f and the downstream groove 26r are provided longer than the maximum width of the printing paper P usable in the printer 22 along the main scanning direction. Absorbing members 27f and 27r for receiving and absorbing the ink droplet Ip are arranged at the bottoms of the upstream groove 26f and the downstream groove 26r, respectively. A portion of the platen 26 upstream of the upstream groove 26f is referred to as an upstream support 26sf. The portion between the upstream groove 26f and the downstream groove 26r of the platen 26 is referred to as a central support 26c. Further, a portion downstream of the downstream groove 26r of the platen is referred to as a downstream support 26sr. The upstream groove portion 26f may be formed as described in claims.
, And the downstream groove 26r corresponds to the “second groove” in the claims. The upstream support portion 26sf corresponds to a “first support portion” in the claims, and the central support portion 26c corresponds to a “second support portion” in the claims.

In order from the upstream side in the sub-scanning direction,
First, the upstream support portion 26sf is provided at a position facing the first nozzle group Nf on the most upstream side among the nozzles on the print head 28 so as to extend in the main scanning direction. The upstream support portion 26sf is provided with a flat upper surface. Next, the upstream groove portion 26f is provided at a position facing the second nozzle group Nh located downstream of the first nozzle group Nf so as to extend in the main scanning direction. Then, the center support portion 26c is located at a position facing the third nozzle group Ni located downstream of the second nozzle group Nh.
It is provided extending in the main scanning direction. Downstream groove 2
Reference numeral 6r is provided at a position facing the fourth nozzle group Nr located downstream of the third nozzle group Ni and extending in the main scanning direction. Lastly, the downstream support portion 26sr
Is provided in the main scanning direction at a position on the downstream side in the sub-scanning direction from the nozzle located at the downstream end in the sub-scanning direction among the nozzles on the print head 28. In addition,
In the print head 28 shown in FIG. 5, the nozzle groups Nf, N
h, Ni, and Nr are shown as hatched portions having different directions and intervals.

Next, the control circuit 40 of the printer 22 (FIG. 3)
) Will be described. Inside the control circuit 40, in addition to the CPU 41, the PROM 42, and the RAM 43, a PC interface 45 for exchanging data with the computer 90, and a drive for outputting ink dot ON / OFF signals to the ink ejection heads 61 to 66. A buffer 44 and the like are provided, and these elements and circuits are interconnected by a bus. The control circuit 40 receives the dot data processed by the computer 90, temporarily stores it in the RAM 43, and outputs it to the driving buffer 44 at a predetermined timing.

In the printer 22 having the hardware configuration described above, the carriage 31 is reciprocated by the carriage motor 24 while the paper P is being conveyed by the paper feed motor 23, and at the same time, the piezo elements of each nozzle unit of the print head 28 are operated. When driven, the ink droplets Ip of each color are ejected, and ink dots are formed to form a multicolor image on the paper P.

In the first image printing mode described later, the upper end Pf of the printing paper P is printed on the downstream groove 26r, and the lower end Pr is printed on the upstream groove 26f. In the vicinity and the vicinity of the lower end, a printing process different from that of the middle portion of the printing paper is performed. In this specification, the printing process in the middle portion of the printing paper is called “intermediate process”, the printing process near the top edge of the printing paper is “top edge process”, and the printing process near the bottom edge of the printing paper is “bottom edge process”. Call. When the upper end processing and the lower end processing are collectively called, they are called “upper / lower end processing”. Then, the print processing performed between the upper end processing and the “intermediate processing” is called “upper end transition processing”, and the “intermediate processing” and the “lower end processing”
The print processing performed during the period is referred to as “lower end shift processing”.

The upstream groove 26f and the downstream groove 26r
Can be determined by the following equation.

W = p × n + α

Here, p is a feed amount of one sub-scan feed in upper and lower end processing. n is the number of sub-scan feeds performed in each of the upper end processing and the lower end processing. α
Is an error of the sub-scan feed assumed in each of the upper end processing and the lower end processing. It is preferable that the value of α in the upstream groove 26f (error in the lower end processing) be set to be larger than the value of α in the downstream groove 26r (error in the upper end processing). If the width of the groove portion of the platen is determined by the above equation, it is possible to provide a groove portion having a width sufficient to receive ink droplets ejected from the nozzles during upper and lower end processing.

B2. FIG. 6 is a plan view showing the relationship between image data D and printing paper P. In the first embodiment, the image data D is set beyond the upper end Pf of the printing paper P to the outside of the printing paper P. Similarly, on the lower end side, the lower end Pr of the printing paper P is also
, The image data D is set up to the outside of the printing paper P. Therefore, in the first embodiment, the image data D
FIG. 6 shows the relationship between the image data D and the size of the printing paper P, and the arrangement of the image data D and the printing paper P during printing.

In this specification, the terms “upper end (part)” and “lower end (part)” are used to refer to the edges of the printing paper P corresponding to the upper and lower parts of the image data recorded on the printing paper P. However, when the edge of the printing paper P is called in accordance with the traveling direction of the sub-scanning feed of the printing paper P on the printer 22, the words "front end (part)" and "rear end (part)" are used. Sometimes.
In the present specification, in the printing paper P, “upper end (part)” corresponds to “front end (part)”, and “lower end (part)” corresponds to “rear end (part)”.

B3. Sub-scan feed during printing: (1) Upper edge processing, upper edge shift processing, and intermediate processing: FIG.
FIG. 4 is an explanatory diagram showing how each raster is recorded by which nozzle near the upper end (leading edge) of the printing paper. Here, for simplicity, the description will be made using only one nozzle row. Each nozzle row has 11 nozzles at intervals of 3 rasters. However, the nozzles used in the upper end processing are only three nozzles on the downstream side in the sub-scanning direction. In FIG. 7, only those three nozzles used for printing are shown, and nozzles not used are not shown.

In FIG. 7, one row of cells arranged vertically represents the print head 28. The numbers 1 to 3 in each cell indicate the nozzle number. In the specification, “#” is added to these numbers to indicate each nozzle. In FIG. 7, the print head 28 is relatively fed in the sub-scanning direction with time.
Are sequentially shifted from left to right. The nozzles surrounded by thick frames are the nozzles that record dots on the raster.

As shown in FIG. 7, in the upper end processing, only nozzles # 1 to # 3 are used. Here, "nozzle # n1
“Use # n2” means “the nozzles # n1 to # n2 can be used as needed”. Therefore, it is sufficient that at least some of the nozzle groups of the nozzle groups # n1 to # n2 are used. In some cases, the nozzle is not used. Further, “do not use nozzles # n3 to # n4” in a certain process means that each nozzle of nozzles # n3 to # n4 is never used in the process.

In the upper end processing, the sub-scan feed of three dots is repeated 12 times. The sub-scan feed for each three dots corresponds to a “first sub-scan mode” described in the claims. The “dot” as the unit of the sub-scan feed amount is
This means a pitch of one dot corresponding to the printing resolution in the sub-scanning direction, which is also equal to the pitch of the raster. The area (see FIG. 7) on the printing paper P recorded during the twelve three-dot feeds corresponds to the "upper end" in the claims.

When the above-described sub-scan feed is performed, each raster is recorded by one nozzle except for some rasters. For example, in FIG. 7, the seventh raster from the top is recorded by nozzle # 1. The eighth raster from the top is recorded by nozzle # 2.

In FIG. 7, the nozzles of the second, third, and sixth raster lines from the top do not pass in the main scanning during printing. Therefore, for these rasters, dots cannot be formed at each pixel by the nozzle. Therefore, in the first image printing mode, the sixth raster from the top is not used for recording an image. That is, the raster that can be used to record an image in the first image print mode is the print head 2
Among the rasters in which the nozzles above No. 8 can record dots, the seventh and subsequent rasters from the upstream end in the sub-scanning direction. A raster area that can be used to record this image is called a “printable area”. A raster area that is not used for image recording is referred to as a “non-printable area”. In FIG. 7, the rasters on which the nozzles on the print head 28 can record dots are numbered sequentially from the top on the left side of the figure. Hereinafter, the same applies to the drawings for explaining the dot recording of the upper end processing.

FIG. 8 is an explanatory diagram showing how each raster is recorded by which nozzle in the upper end processing, the upper end transition processing, and the intermediate processing. Printer 2
No. 2 performs the upper end shift processing using the nozzles # 1 to # 11 after performing the upper end processing. In the upper end transition processing, the same sub-scan feed of three dots as in the upper end processing is repeated four times. The area (see FIG. 8) on the printing paper P recorded during the four three-dot feeds corresponds to an “upper end transition part” in the claims.

After the upper end shifting process, the process shifts to an intermediate process of performing dot regular printing of 11 dots using nozzles # 1 to # 11 to print dots. Such a method of performing sub-scanning at a constant feed amount is called "regular feed". The sub-scan feed of each 11 dots corresponds to a “second sub-scan mode” described in claims. The area (see FIG. 8) on the printing paper P recorded during the sub-scan feed of 11 dots corresponds to an "intermediate portion" in the claims.

In FIG. 8, the 79th or 8th from the top
In the 0th raster, two nozzles pass in the main scan during printing. In such a raster in which two or more nozzles pass in printing, it is assumed that only one of the nozzles records dots. Here, it is assumed that the nozzle that last passes through the raster records dots. It is preferable that these rasters are recorded by the nozzles passing over the rasters after shifting to the upper end shift processing or the intermediate processing as much as possible. In the upper end transition processing and the intermediate processing, a larger number of nozzles are used than in the upper end processing. For this reason, the characteristics of the small number of nozzles are not strongly reflected in the print result, and the print result can be expected to have high image quality.

As a result of performing the printing as described above, the area from the seventh raster to the 51st raster counted from the uppermost raster where the print head can record dots is nozzle # 1, # 2, # 3 (the fourth nozzle group Nr). Then, the 52nd and subsequent rasters are #
Recording is performed using Nos. 1 to # 11 (nozzle groups Nr, Ni, Nh, Nf). The relationship between these rasters and the printing paper P and their effects will be described below.

In the first embodiment, an image is recorded without margins up to the upper end of the printing paper. As described above, in the first embodiment, among the rasters on which the nozzles on the print head 28 can record dots, the rasters (printable areas) from the seventh edge from the upstream end in the sub-scanning direction are used. Images can be recorded (see FIG. 7). Therefore, if the printing paper is arranged with respect to the print head 28 and the recording of the dots is started so that the seventh raster from the end is located at a position almost at the upper end of the printing paper, theoretically, Images can be recorded up to the upper end of the printing paper. However, during the sub-scan feed, an error may occur in the feed amount. Further, the ejection direction of the ink droplet may be shifted due to a manufacturing error of the print head or the like. For this reason, it is preferable that no margin is formed at the upper end of the printing paper even when the landing position of the ink droplet on the printing paper is shifted. Therefore, in the first image print mode, the image data D used for printing is set from the seventh raster from the upstream end in the sub-scanning direction among rasters on which the nozzles on the print head 28 can record dots. And printing paper P
Printing is started from a state where the upper end of is located at the 23rd raster position from the upstream end in the sub-scanning direction. Therefore, the assumed position of the upper end of the printing paper with respect to each raster at the start of printing is the position of the 23rd raster from the upstream end in the sub-scanning direction, as shown in FIG. That is, in the first embodiment, the width of the portion of the image data D set beyond the upper end Pf of the printing paper P to the outside of the printing paper P (see FIG. 6).
Is for 16 rasters. On the other hand, the lower end Pr of the printing paper P
, The width of the portion of the image data D set to the outside of the printing paper P is also 24 rasters. The raster at the lower end will be described later.

FIG. 9 is a side view showing the relationship between the print head 28 and the printing paper P at the start of printing. Here, the center supporting portion 26c of the platen 26 extends from the position two rasters upstream from the nozzle # 4 of the print head 28 to the position downstream two rasters from the nozzle # 6.
26. The upstream groove 26f is provided in a range from a position one raster downstream from the nozzle # 7 to a position two rasters upstream from the nozzle # 9. The downstream groove 26r is provided in a range from a position two rasters downstream from the nozzle # 1 to a position two rasters upstream from the nozzle # 3. For this reason, even when the ink droplets Ip are ejected from each nozzle in a state where there is no printing paper, the ink droplets of the nozzles # 1, # 2, and # 3 land on the downstream groove 26r, and the nozzles # 7, # 8, The # 9 ink droplet is in the downstream groove 2
Lands at 6r. That is, ink droplets from those nozzles do not land on the central support portion 26c of the platen 26.

The fourth nozzle group Nr shown in FIGS. 4 and 5 is the nozzles # 1, # 2, and # 3 in FIG. A downstream groove 26r is provided below a portion through which the nozzles pass during main scanning (FIG. 5).
reference). In FIG. 9, when the upper end Pf of the printing paper P is located at a position indicated by a solid line on the downstream groove 26r,
Printing starts.

As described above, at the start of printing, the upper end Pf of the printing paper P is located at the position of the 23rd raster from the upstream end in the sub-scanning direction among the rasters on which the nozzles on the print head 28 can record dots. It is in. That is, with reference to FIG. 9, the upper end of the printing paper P is located two rasters later than the nozzle of # 6. Therefore, if printing is to be started from this state, the uppermost raster of the printable area (in FIG.
The third raster) should be recorded by the nozzle # 3, but there is no printing paper P below the nozzle # 3. Therefore, the printing paper P is transferred to the upstream paper feed rollers 25a, 25a.
If it is accurately sent by b, the ink droplet Ip ejected from the nozzle # 3 will fall directly into the downstream groove 26r. The same applies to the case of recording the 16th raster from the top of the printable area (the 22nd raster from the top in FIG. 7).

However, for some reason, the printing paper P
If is sent more than the original feed amount,
There is a case where the upper end of the printing paper P comes to the position of the 22nd raster from the top of the printable area or the raster above it. In the first embodiment, even in such a case, # 1,
Since the nozzles # 2 and # 3 eject the ink droplets Ip to the rasters, an image can be recorded on the upper end of the printing paper P, and no margin is generated. That is, even when the printing paper P is sent more than the original feeding amount, as shown by the dashed line in FIG. 9, when the extra feeding amount is equal to or less than 16 rasters, the printing paper P There is no margin at the top of the file.

Conversely, for some reason, the printing paper P may be sent less than the original feed amount. In such a case, there is no printing paper at the position where the printing paper should be, and the ink droplet Ip lands on the lower structure. However, as shown in FIGS. 7 and 8, in the first image print mode, 29 rasters (up to the 51st raster in FIG. 8) from the assumed upper end position of the paper are # 1, # 2, and # 3. It is to be recorded by the nozzle. Downstream grooves 26r are provided below these nozzles.
Even if does not land on the printing paper P, the ink droplet Ip falls into the downstream groove 26r and is absorbed by the absorbing member 27r. Therefore, the ink droplets Ip do not land on the upper surface of the platen 26 and do not stain the printing paper later. That is, in the first embodiment, even when the upper end Pf of the printing paper P is behind the assumed upper end position at the start of printing, if the deviation amount from the assumed upper end position is 29 rasters or less, the ink drop Ip does not land on the upper surface of the platen 26, and does not stain the printing paper P later.

In the first embodiment, in the intermediate processing, printing is performed using nozzles. Therefore, high-speed printing can be performed in the intermediate processing.

Further, in the first embodiment, in the upper end transition processing prior to the intermediate processing after the upper end processing, the same sub-scan feed as in the upper end processing is performed using all the nozzles as in the intermediate processing. Therefore, the transition from the upper end processing to the intermediate processing can be smoothly performed without performing reverse feed in the sub-scanning. Therefore, the quality of the print result is high.

The effect described above is as follows. When printing the upper end of the printing paper P, when the upper end of the printing paper P is above the opening of the downstream groove 26r, the fourth nozzle group Nr (the fourth partial dot It is obtained by ejecting ink droplets from at least a part of the formation element group) to form dots on the printing paper P.

As described above, the fourth nozzle group N
r (nozzles # 1, # 2, # 3) and the nozzle groups Nr, Ni, Nh, Nf (nozzles # 1 to # 1)
The upper end shift processing and the intermediate processing according to 1) are executed by the CPU 41.
(See FIG. 3). That is, the CPU 41
Function as an “upper end printing section”, an “upper end transition printing section”, and an “intermediate printing section” in the claims. These CPUs
FIG. 3 shows an upper end printing unit 41p, an upper end transition printing unit 41q, and an intermediate printing unit 41r as functional units 41.

(2) Lower end shift processing and lower end processing: FIG.
FIGS. 0 to 12 are explanatory diagrams showing how each raster is recorded by which nozzle in the lower end shift processing and the lower end processing. In the first embodiment, FIG.
As shown in, in the intermediate processing, all nozzles are used,
After repeating the regular feeding of 11 dots, in the lower end shift processing, nozzles # 1 to # 9 (nozzle groups Nr, Ni, N
Using h), a dot is formed by feeding three dots at a time five times. That is, in the lower end shift processing, the first nozzle group Nf (nozzles # 10 and # 11) is not used. The area (see FIGS. 10 and 11) on the printing paper P recorded during the five three-dot feeds corresponds to a “lower end transition portion” in the claims.

Then, as shown in FIGS. 11 and 12, after the lower end shift processing, in the lower end processing, # 7 to # 9 are executed.
Using only the nozzles (second nozzle group Nh), dots are formed by feeding three dots 17 times each. This 3
The regular feed of each dot corresponds to the “third
Sub-scanning mode ”. And this 17 times 3
An area on the printing paper P recorded during the dot feeding (FIG. 1)
1, refer to FIG. 12).
Is equivalent to The “upper end”, “upper transition”, “intermediate”, “lower transition”, and “lower end” of the printing paper P are
Although they partially overlap each other, they are arranged in order from the top on the surface of the printing paper P.

When such a feed is performed, each raster along the main scanning direction is recorded by one nozzle except for a part of the rasters. In FIGS. 10 to 12, the rasters on which the nozzles on the print head 28 can record dots are numbered sequentially from the bottom on the right side of the drawing. Hereinafter, the same applies to the drawings for explaining the printing of dots in the lower end processing.

In FIG. 12, the nozzles of the second, third, and sixth raster lines from the bottom do not pass in the main scanning during printing. Therefore, the printable area in the lower end portion of the printing paper is an area of the seventh or more rasters from the bottom.

In FIG. 10, the 80th and 81st rasters from the bottom are 2nd rasters in the main scan during printing.
More than one nozzle passes. The same applies to the 59th and 63rd rasters from the bottom in FIG. For such a raster in which two or more nozzles pass in printing, the nozzle that first passes through the raster records dots. Such a raster is preferably recorded by nozzles passing over the raster in the intermediate processing, the intermediate processing and the lower end shift processing. In the intermediate processing and the lower end transition processing, a larger number of nozzles are used than in the lower end processing. For this reason, the characteristics of the small number of nozzles are not strongly reflected in the print result, and the print result can be expected to have high image quality.

When the printing as described above is performed, as shown in FIGS. 11 and 12, the area up to the 58th raster counted from the lowest raster where the print head can record dots is nozzle # 7. , # 8, # 9 (second nozzle group Nh)
Will be recorded. Then, the 59th or more rasters are # 1 to # 11 (nozzle groups Nr, Ni, Nh,
Nf). The relationship between these rasters and the printing paper P and their effects will be described below.

In the first image print mode, as in the case of the upper end, an image is recorded without a margin at the lower end. As described above, in the first embodiment, among the rasters on which the nozzles on the print head 28 can record dots, the seventh or more rasters (printable area) from the downstream end in the sub-scanning direction are used. Images can be recorded. However, in consideration of a case where an error occurs in the feed amount during the sub-scan feed, the recording is performed on the printing paper from the 31st raster from the downstream end in the sub-scan direction. That is, in a state where the lower end of the printing paper is at the position of the 31st raster from the upstream end in the sub-scanning direction, the ink droplets Ip are ejected also for the 30th and lower rasters, and the last main scan at the time of printing is performed. Do.
Therefore, the assumed position of the lower end of the printing paper with respect to each raster at the end of printing is the position of the 31st raster from the downstream end in the sub-scanning direction, as shown in FIG.

FIG. 13 is a plan view showing the relationship between the upstream groove 26f and the printing paper P when printing the lower end Pr of the printing paper P. In FIG. 13, the second nozzle groups Nh in the shaded portions of the print head 28 are # 7, # 8, #
9 nozzles. An upstream groove 26f is provided below a portion through which the nozzles pass during main scanning. Then, when the lower end Pr of the printing paper P is located at the position indicated by the one-dot chain line on the upstream side groove 26f, the actual recording of the dots on the printing paper P ends.

FIG. 14 is a side view showing the relationship between the print head 28 and the printing paper P when printing the lower end Pr of the printing paper P. As described above, when printing the lower end Pr of the printing paper P, the lower end Pr of the printing paper P is
The nozzle on No. 8 is at the position of the 31st raster from the downstream end in the sub-scanning direction among the rasters capable of recording dots (see FIG. 12). That is, when the raster at the lower end of the printing paper P is recorded, the lower end of the printing paper P is immediately below the nozzle # 9. Therefore, after that, even if the ink droplets are ejected from the nozzles # 7 to # 9 by performing the sub-scan feed,
The ejected ink droplet Ip is used as it is in the upstream groove portion 26f.
Will fall.

However, for some reason, the printing paper P
Is smaller than the original feed amount, the nozzles # 7, # 8, and # 9 are moved to the lower end Pr of the printing paper P.
Raster set beyond (7 in FIG. 12 from the bottom)
Ink droplets Ip for the rasters
Is ejected, an image can be recorded on the lower end Pr of the printing paper P, and no margin is formed. That is, when the insufficient feed amount is equal to or less than 24 rasters, no margin is formed at the lower end of the printing paper P.

Then, the upper 28
The rasters (the 31st to 62nd rasters from the bottom in FIG. 11) are to be recorded by nozzles # 7, # 8 and # 9. Therefore, even if the printing paper P is sent more than the original feeding amount for some reason, the ejected ink droplet Ip may fall into the upstream groove 26f and land on the upper surface of the platen 26. Absent.

The effect described above is as follows. When printing the lower end of the printing paper P, when the lower end of the printing paper P is above the opening of the upstream groove 26f, the second nozzle group Nh (the second partial dot It is obtained by ejecting ink droplets from at least a part of the forming element group and forming dots on the printing paper P.

In the first embodiment, printing is performed using nozzles in the intermediate processing. Therefore, high-speed printing can be performed in the intermediate processing.

Further, in the first embodiment, the nozzle group N
h, Ni, Nr (nozzles # 1 to # 9) only. That is, the first nozzle group Nf (nozzles # 10, # 11) located upstream of the second nozzle group Nh used in the lower end processing is not used. Therefore, the transition from the intermediate processing to the lower end processing can be smoothly performed without performing reverse feed in the sub-scanning. Therefore, the quality of the print result is high.

As described above, the nozzle groups Nh and N
The lower end shift processing by i, Nr (nozzles # 1 to # 9) and the lower end processing by the second nozzle group Nh (nozzles # 7, # 8, # 9) are performed by the CPU 41 (see FIG. 3). That is, the CPU 41 functions as a “lower end printing section” and a “lower end printing section” in the claims.
The lower end shift printing unit 41 as a functional unit of the CPU 41
FIG. 3 shows s and the lower end printing unit 41t.

C. Second Embodiment: FIG. 15 is a side view showing the relationship between the print head 28a, the upstream groove 26fa, and the downstream groove 26ra in the second embodiment. Here, a description will be given of a printing apparatus in which one nozzle row has 48 nozzles. In the first embodiment, the regular scanning is performed in the sub-scanning feed. In the second embodiment, the irregular scanning is performed. The “irregular feed” is a method of performing sub-scanning by combining different feed amounts. In the second embodiment, each raster is printed by two different nozzles by two main scans. In this manner, a method of printing by sharing the pixels in one raster by a plurality of nozzles is called “overlap printing”. In overlap printing, in one raster, dots are recorded by a plurality of nozzles passing on the raster in a plurality of main scans in which the position of the printing paper in the sub-scanning direction with respect to the print head is different from each other.

In the printing apparatus according to the second embodiment, the upstream side support portion 26sf moves the nozzles # 35 to # 4 in the sub-scanning direction.
8 (first nozzle group Nfa). In addition, the upstream side groove portion 26fa includes the nozzles # 31 to # 31.
34 (second nozzle group Nha). The central support portion 26ca has nozzles # 6 to # 30.
(Third nozzle group Nia). The downstream groove 26ra is provided with the nozzles # 1 to # 5.
(A fourth nozzle group Nra). Other points are the same as those of the printing apparatus of the first embodiment.

The first nozzle group Nfa in the second embodiment
Corresponds to a “first partial dot forming element group” in the claims, and the second nozzle group Nha corresponds to a “second partial dot forming element group” in the claims. The third nozzle group Nia corresponds to the “third partial dot forming element group” in claims, and the fourth nozzle group Nra
Corresponds to a “fourth partial dot forming element group” in the claims. Note that, here, the partial dot forming element groups of each nozzle array are collectively handled, and are respectively referred to as nozzle groups Nfa, Nha, Nia, and Nra.

(1) Upper end processing, upper end transition processing, and intermediate processing: FIG. 16 is an explanatory diagram showing how each raster is recorded by which nozzle in the upper end processing of the second embodiment. As shown in FIG. 16, in the upper end processing of the second embodiment, the fourth nozzle group Nra (nozzles # 1 to # 5) is used to make two dots, three dots, two dots, two dots, and one dot. , 2 dot feed in that order 7
Repeat twice. However, actually, the fourth nozzle group Nra
Of these, nozzle # 5 is not used. At the beginning of the sub-scan feed, the sub-scan feed of three dots, two dots, two dots, one dot, and two dots is performed without performing the first two-dot feed. The irregular feeding of two dots, three dots, two dots, two dots, one dot, and two dots performed in the upper end process corresponds to a “first sub-scanning mode” described in the claims. It should be noted that nozzles surrounded by thick frames in the figure are nozzles that record dots on a raster.

After the upper end processing, all nozzles # 1 to # 48 (nozzle groups Nra, Ni
a, Nha, Nfa).
In the upper end shift processing, the sub-scan feed is performed a total of 12 times.

FIG. 17 is an explanatory diagram showing how each raster is recorded by which nozzle in the intermediate processing of the second embodiment. After the upper edge transition processing, FIG.
Then, the process proceeds to the intermediate processing as shown in FIG.
The irregular feeding of dots, 21 dots, and 26 dots is repeated. This irregular feed corresponds to the "second sub-scanning mode" described in the claims. In the “second sub-scanning mode” in the intermediate processing, another feeding method may be used as long as the maximum feeding amount is larger than the maximum sub-scanning feeding amount in the upper end processing.

As a result of the above-described feeding, each raster is printed by two nozzles by two main scans.
As shown in FIG. 16, for a raster such as the 25th or 28th raster from the top, which passes through three or more nozzles, only the last two nozzles passing the raster record dots. And

As shown in FIG. 16, in the second embodiment, among the rasters on which the nozzles on the print head 28 can record dots, the 19th and subsequent rasters (print area) from the upstream end in the sub-scanning direction are used. Thus, an image can be recorded. Therefore, the image data D used for printing is set from the 19th raster from the upstream end in the sub-scanning direction. However, for the same reason as in the first embodiment, printing is performed on the printing paper P.
Does not start at the 19th position from the upstream end in the sub-scanning direction but at a later position. That is, also in the second embodiment, the image data D is provided beyond the assumed upper end position of the printing paper P.

In the second embodiment, printing is performed using all the nozzles in the intermediate processing. Therefore, printing can be performed at a higher speed than when some of the nozzles are not used. In the second embodiment, all the nozzles are used between the upper end processing and the intermediate processing as in the intermediate processing, and the same feed (2 dots, 3 dots, 2 dots,
An upper end shift process for performing dot, dot, and dot feeds is performed. Therefore, when shifting from the upper end processing to the intermediate processing, reverse feeding is not required, and printing can be performed smoothly. Therefore, the quality of the print result is high.

(2) Lower end shift processing and lower end processing: FIG.
FIG. 8 is an explanatory diagram showing how each raster is recorded by which nozzle in the intermediate processing, lower end shift processing, and lower end processing of the second embodiment. The table shown in the upper part of the figure shows the respective sub-scan feed amounts. In the second embodiment, as shown in FIG. 18, in the intermediate processing, the irregular feed of 20, 27, 22, 28, 21, and 26 dots is repeated using all the nozzles, and then the lower end shift is performed. Nozzles # 1 to # in processing
34 (nozzle group Nra, Nia, Nha)
Dot, 3 dot, 2 dot, 2 dot, 1 dot, 2
The dot feeding is repeated eight times in that order (2 times, 3 dots, 2 dots, 2 dots, 1 dot, 2 dots, 2 dots, 3 dots, 8 times). After that, in the lower end processing, the nozzles # 31 to # 34 (the second nozzle group Nh
Using only a), continue with 2 dots, 3 dots, 2 dots
The feeding of dots, two dots, one dot, and two dots is repeated. These 2 dots, 3 dots, 2 dots, 2 dots, 1 dot
The irregular feeding of dots and two dots corresponds to a “third sub-scanning mode” described in the claims. When the above printing is performed, each raster is recorded by two nozzles in two main scans. For a raster through which three or more nozzles pass, only two of the nozzles record dots. As a result, for example, in the lower end processing, in a certain main scan, there is a case where there is an unused nozzle among the nozzles # 31 to # 34.

In the second embodiment described above, between the intermediate processing and the lower end processing, the first nozzle group Nfa (nozzles # 35- #) located upstream of the second nozzle group Nha
48) without using the same feed (2 dots,
A lower end shift process for performing irregular feeding of three dots, two dots, two dots, one dot, and two dots) is performed. For this reason, when shifting from the intermediate processing to the lower end processing, reverse printing is not required, and printing can be performed smoothly. For this reason,
High quality print results.

Further, in the second embodiment, irregular feeding is performed through upper end processing, upper end shifting processing, intermediate processing, lower end shifting processing, and lower end processing. For this reason, the quality of the print result is higher than in the case of performing the regular feed. Further, since the overlap printing is performed, the quality of the printing result is higher than the case where the overlap printing is not performed.

D. Third Embodiment (1) Outline of Third Embodiment: FIG. 19 is an explanatory diagram showing a change in the nozzles used on the print head 28 in the third embodiment. 19, as in FIG. 1, the lower surface of the print head 28 is shown on the left side, and the configuration of the platen 26 corresponding to each nozzle on the print head 28 is shown on the right side as a side view. In the printer of the third embodiment, the nozzle rows K, C, LC, M, LM, and Y of the color of the print head 28 are located at the positions facing the downstream-side support portion 26sr, respectively.
#B. These nozzles #A and #B
Nozzle group Nt. This fifth nozzle group Nt
Is located downstream of the fourth nozzle group Nr, and the downstream support portion 26sr corresponds to a “third support portion” in the claims. The other points of the hardware configuration of the printer of the third embodiment are the same as those of the printer of the first embodiment. It should be noted that the nozzles # lined up from downstream to upstream in each nozzle row
The 13 nozzles A to # 11 have a constant nozzle pitch k
= 4.

In the printing of the third embodiment, the nozzles #A and #B are used in the intermediate processing and the lower end shift processing.
This is different from the printing of the first embodiment. Other points are the same as the printing in the first embodiment.

In the printer of the third embodiment, when the upper end of the printing paper is located on the downstream groove 26r, the fourth nozzle group Nr facing the downstream groove 26r.
Printing is performed only by the upper end (upper edge processing). When the lower end of the printing paper is on the upstream groove 26f, the second nozzle group Nh facing the upstream groove 26f.
Only the printing is performed (lower end processing). In addition, the intermediate portion of the printing paper performs printing using all the nozzle groups including the nozzle group Nt (nozzles #A and #B) (intermediate processing).

Further, the same sub-scan feed as in the upper end processing is performed between the upper end processing and the intermediate processing, and Nf, Nh, Ni, Nr
Is performed to perform the upper end shift processing for printing. In the upper end shift processing, the nozzle group Nt is not used. Further, between the intermediate processing and the lower end processing, the same sub-scan feed as in the lower end processing is performed, and the lower end transition processing for performing printing using the nozzle groups Nh, Ni, Nr, Nt is performed. In the lower end transition process,
No nozzle group Nf is used.

(2) Upper end processing, upper end transition processing, and intermediate processing: FIG. 20 is an explanatory diagram showing how each raster is recorded by which nozzle near the upper end (top end) of the printing paper. . FIG. 21 is an explanatory diagram showing how each raster is recorded by which nozzle in the upper end processing, the upper end shift processing, and the intermediate processing. In the third embodiment, the nozzles used in the upper end processing are only the nozzles # 1 to # 3 located at positions facing the downstream groove 26r. In FIG. 20, nozzle numbers are shown only for the three nozzles used for printing, and unused nozzles including nozzles #A and #B are indicated by "*". The nozzles responsible for recording each raster in the printable area are surrounded by a thick frame.

In the upper end processing, as in the first embodiment,
The sub-scan feed of three dots is repeated 12 times. This sub-scan feed of three dots is referred to as “first
Sub-scanning mode ”. The area on the printing paper P recorded during the twelve three-dot feeds (see FIG. 20)
Corresponds to the “upper end” in the claims. In the third embodiment, the printable area is 15
The raster areas after the first raster are the non-printable areas.

As shown in FIG. 20, in the third embodiment, the assumed upper end position of the printing paper is the position of the 30th raster. On the other hand, in the third embodiment, the region from the 15th raster to the 50th raster (not shown in FIG. 20) from the top is recorded in the upper end process using only the nozzles # 1 to # 3. That is, the fifteen rasters on the outer side (upstream side) of the printing paper and the twenty-first raster on the inner side (downstream side) sandwich the upper end of the printing paper at the position of the thirty-third raster, and face the downstream groove 26r. Is recorded in the main scan using only the nozzles # 1 to # 3. In these main scans, no ink droplets are ejected from other nozzles. Therefore, by performing such upper end processing, printing can be performed without margins up to the upper end of the printing paper without soiling the platen.

After performing the upper end processing, the printer of the third embodiment performs the upper end shift processing using the nozzles # 1 to # 11 (see FIGS. 19 and 21). In the upper end transition processing, the same sub-scan feed of three dots as in the upper end processing is repeated four times. The area (see FIG. 21) on the printing paper P recorded during the four three-dot feeds corresponds to an “upper end transition portion” in the claims.

After the upper end shifting process, the process shifts to the intermediate process of printing dots by performing regular feeding of 13 dots using all the nozzles #A to # 11. This sub-scan feed of 13 dots corresponds to a “second sub-scan mode” described in the claims. The area (see FIG. 21) on the printing paper P recorded during the sub-scan feed of 13 dots corresponds to the "intermediate portion" in the claims.
By performing such upper end shift processing, it is possible to smoothly shift from upper end processing to intermediate processing. In addition, since printing is performed using all nozzles in the intermediate processing, printing can be performed at high speed.

(3) Lower end shift processing and lower end processing: FIG.
FIGS. 2 and 23 are explanatory diagrams showing how each raster is recorded by which nozzle in the lower end shift processing and the lower end processing. In the third embodiment, in the intermediate processing, the regular feeding of 13 dots is repeated using all the nozzles. Then, in the lower end shift processing, # A ~
Using # 9 nozzles (nozzle groups Nt, Nr, Ni, Nh), three dots are fed five times to form dots (see FIG. 19). In the lower end shift processing, the first nozzle group Nf (nozzles # 10 and # 11) is not used. The area on the printing paper P recorded during the five three-dot feeds (see FIGS. 22 and 23) corresponds to a “lower end transition part” in the claims.

As shown in FIG. 23, after the lower end shift processing,
In the lower end processing, dots are formed by performing three dot feeds thirteen times using only nozzles # 7 to # 9 (second nozzle group Nh) (see FIG. 19). This regular feed of three dots corresponds to a “third sub-scanning mode” described in the claims. The area (see FIGS. 22 and 23) on the printing paper P recorded during the thirteen three-dot feeds corresponds to a “lower end” in the claims. In the third embodiment, since the lower end transition processing is performed prior to the lower end processing, it is possible to smoothly transition from the intermediate processing to the lower end processing.

As shown in FIG. 23, in the third embodiment, the non-printable area at the lower end of the printing paper extends from the lowest raster where the print head can record dots to the 14th raster. is there. The printable area is the area of the fifteenth or more rasters from the lowermost raster.

As shown in FIG. 23, in the third embodiment, the assumed lower end position of the printing paper is the position of the 31st raster counted from the lowermost raster where the print head can record dots. In the third embodiment, the region from the 15th raster to the 47th raster from the bottom is the nozzle #
It is recorded in the lower end process using only 7 to # 9.
That is, 16 rasters on the outer side (downstream side) across the lower end of the printing paper and 17 rasters on the inner side (upstream side) are:
Nozzles # 7 to # 7 at positions facing the upstream groove 26f
Recorded only in # 9. Therefore, by performing such lower end processing, printing can be performed without margins up to the upper end of the printing paper without soiling the platen.

(3) Influence of Performance of Each Nozzle on Printing Result: FIG. 24 is a graph showing a difference in performance of each nozzle arranged in the sub-scanning direction. FIG. 24A is a graph showing the ink droplet ejection speed of each nozzle arranged in the sub-scanning direction. Here, in order to clearly show the relationship between the nozzle position and the performance in the nozzle row, a graph is shown for a nozzle row having 48 nozzles in one row. As shown by the solid line and the one-dot chain line in FIG. 24A, the variation of the ejection speed Vk of the ink droplet from the nozzle from the design value Vk0 tends to be larger at the nozzle at the end. That is, for the nozzles near the center nozzle # 24, the ejection speed is relatively close to the design value Vk0, but for the nozzles near the nozzle # 1 and the nozzle # 48 at the end in the sub-scanning direction, the ejection speed is relatively designed. The deviation from the value Vk0 is large. As shown by the solid line in the drawing, the ejection speed Vk of the ink droplet may be larger than the design value Vk0 at the nozzle at the end, and the ejection speed of the ink droplet at the nozzle at the end may be higher at the end nozzle as shown by the dashed line. It may be smaller than the design value. Furthermore, at one end, the ejection speed of the ink droplet may be lower than the design value at the nozzle at the end, and at the other end, the ejection speed may be higher at the nozzle at the end.

In addition, the variation in the direction in which the ink droplets are ejected from each nozzle, as well as the variation in the ejection speed of the ink droplets, may be greater at the end nozzle in the sub-scanning direction. As described above, for various reasons, the deviation of the dot forming position on the printing paper may be larger at the end nozzle in the sub-scanning direction.

FIG. 24B is a graph showing the weight of ink droplets ejected from each nozzle arranged in the sub-scanning direction. FIG. 24 (b) also shows a graph for a nozzle row having 48 nozzles in one row in order to clearly show the relationship between the nozzle position and the performance in the nozzle row. As for the weight Iw of the ink droplet, the deviation from the design value Iw0 is larger at the nozzles at the end. Regarding the tendency of the variation, as shown by the solid line in FIG. 24B, the weight of the ink droplet may be larger at the end nozzle, and as shown by the dashed line, the ink droplet may be closer to the end nozzle. In some cases, the weight may be reduced. In addition, for one end, the weight of the ink droplet may be smaller at the end nozzle, and at the other end, the weight may be larger at the end nozzle. When the weight of ink drops varies,
The size of the dots on the printing paper will vary. Therefore, the use of nozzles near the edges in printing may degrade the quality of the printing result.

When the upper end processing or the lower end processing is performed using the printing apparatus having such a tendency, it is preferable not to use the nozzle at the end. In the upper end processing or lower end processing in which printing is performed by only some of the nozzles, when only the nozzles located at the end are used, the quality of the printing result is particularly poor compared to the intermediate processing using all the nozzles. It is because it is considered to be.

When printing the end portion, the printing paper may be instructed by only one of the upstream paper feed rollers 25p and 25q and the downstream paper feed rollers 25r and 25s. Further, the ends Pf and Pr of the printing paper P may be on the groove and may not be supported from below by the support. In such a case, the printing paper may slightly bulge upward or deflect downward. For this reason, even if the ink droplet is ejected accurately, it may not land at an accurate position on the printing paper. Therefore,
If ejection of ink droplets is not performed accurately, there is a possibility that the dot formation position is greatly shifted as compared with printing at the center of the printing paper. Therefore, in printing on the edge of the printing paper, the demand for ejecting ink droplets with high accuracy is higher than that in printing on the center of the printing paper.

In the third embodiment, the nozzles #A and #B located at the downstream end are not used in the upper end processing. The nozzles # 1 to # 3 (nozzle group Nr) that print the upper end of the printing paper have a deviation in dot formation position and an error in dot size with respect to the nozzles #A and #B (nozzle group Nt). The nozzle is considered to be small. For this reason, there is a high possibility that the quality of the printing result of the upper end portion of the printing paper will be higher. Also, nozzles # 11 and # 1 located at the upstream end
2 (nozzle group Nf) is not used in the lower end processing. Then, nozzles # 7 to # 7 that print the lower end of the printing paper
The nozzle # 9 (nozzle group Nh) is a nozzle that is considered to have a small dot formation position deviation and a small dot size error with respect to the nozzles # 11 and # 12 (nozzle group Nf). For this reason, there is a high possibility that the quality of the printing result at the lower end of the printing paper will be higher.

The deviation of the dot formation position on the printing paper of each nozzle and the deviation of the ink droplet ejection speed are shown in FIG.
It does not necessarily need to match the curve of the graph as shown in (a) and (b). That is, if the average positional deviation of the dot formation positions of the nozzles of the nozzle group Nr on the print medium is smaller than the average positional deviation of the dot formation positions of the nozzle group Nt, the upper end processing as in the third embodiment is performed. In addition, the quality of the printing result can be improved. If the average positional deviation of the dot formation positions of the nozzles of the nozzle group Nh on the print medium is smaller than the average positional deviation of the dot formation positions of the nozzle group Nf, the lower end processing as in the third embodiment is performed. In addition, the quality of the print result can be improved.

Similarly, if the nozzles of the nozzle group Nr have smaller average deviations of the ejection speed of the ink droplets than the nozzles of the nozzle group Nt, as a result, the dot formation position on the print medium in the upper end processing is consequently increased. High-quality printing can be performed by using a nozzle having a small average positional deviation amount. Then, if the nozzles of the nozzle group Nh have a smaller average shift amount of the ink droplet ejection speed than the nozzles of the nozzle group Nf, as a result, in the lower end processing, the average position shift of the dot formation position on the print medium is reduced. High quality printing can be performed using a small amount of nozzles. In addition,
Such an effect is similarly exerted in the first embodiment and the second embodiment in which the nozzle group Nh is used without using the nozzle group Nf positioned at the uppermost stream in the lower end processing.

(4) Determining the amount of deviation of the dot formation position: FIG. 25 is an explanatory diagram showing the principle of the diaphragm inspection method. FIG.
5 includes a diaphragm 52a constituting the dot missing inspection unit 52.
And the microphone 52b. The piezo element PE provided for each nozzle n is installed at a position in contact with an ink passage 80 for guiding ink to the nozzle n. When an ink droplet ejection signal is sent to the piezo element PE, the piezo element PE deforms one side wall of the ink passage 80 and ejects the ink droplet Ip from the tip of the nozzle n. The ink drop I
When p reaches the diaphragm 52a, the diaphragm 52a vibrates. The microphone 52b converts the vibration of the diaphragm 52a into an electric signal. If the time difference between the time when the electric signal is detected and the time when the ink droplet ejection signal is sent to the piezo element PE is determined, the flight time ti of the ink droplet Ip can be substantially determined.

The deviation of the dot formation position can be calculated as follows. Assuming that the distance from the nozzle n to the diaphragm 52a is Ls, the flying speed Vk of the ink droplet Ip
Can be calculated by the following equation. When this Vk is recorded side by side for each nozzle, a graph as shown in FIG.

Vk = Ls / ti (1)

FIG. 26 is an explanatory diagram showing the relationship between the positions of nozzles for ejecting ink droplets and the landing positions of ink droplets.
The nozzle n on the print head 28 is sent at a speed Vs from left to right in the figure by main scanning. Assuming that the distance from the nozzle n to the printing paper P at the time of printing is Lp, the time tp from when the ink droplet Ip is ejected to when it lands on the printing paper P is obtained by dividing Lp by the previously obtained Vk. Can be

Tp = Lp / Vk (2)

Further, the difference Dm between the position of the nozzle in the main scanning direction when the ink droplet is ejected and the landing position of the ink droplet in the main scanning direction is the main scanning speed V of the print head.
From s, it can be obtained by the following equation.

Dm = Vs × tp (3)

One reference nozzle is determined from the nozzles of the print head 28, and the difference Dm between the ink droplet ejection position and the ink droplet landing position of the nozzle is set to Dm0. Then
Deviation Dd of the dot formation position of each nozzle in the main scanning direction
(I) (i is a nozzle number) is determined by the following equation. Dm (i) is the difference between the ink droplet ejection position of the nozzle i and the ink droplet landing position.

Dd (i) = Dm (i) −Dm0 (4)

The average deviation amount of the dot formation positions of the nozzle groups can be obtained by averaging Dd for each nozzle group. Here, one reference nozzle is determined, and the difference Dm between the ink droplet ejection position and the ink droplet landing position of the nozzle is set as the reference value Dm0. However, Dm0 can be determined in other ways. For example, the average value of Dm (i) of all the nozzles or a predetermined part of the nozzles is represented by D
m0 can also be used.

Although the amount of deviation of the dot formation position is calculated from the flight time of the ink droplets here, it can be obtained by other methods. For example, an ink droplet ejection signal is sent to a plurality of nozzles at the same timing. Then, dots may be actually formed on the printing paper, and the dot formation position may be measured. For example, print head 2
From among the eight nozzles, one reference nozzle is determined.
Original positions (assumed positions) of dots formed by other nozzles
Should be obtained based on the design value from the position of the dot formed by the reference nozzle. The deviation between the assumed position and the actual dot position is measured in the main scanning direction and the sub-scanning direction, and the deviation amount of the dot formation position can be obtained. In this case, it is preferable that the position of each dot is automatically read by the optical sensor.

When the deviation from the dot position is measured in the main scanning direction and the sub-scanning direction, and the average of the dot formation position deviation of each nozzle group is obtained to evaluate the size,
The distance Dc between the assumed position of the dot and the actual position can be used as a reference. The dot forming position shift amount in the main scanning direction is Dd, and the dot forming position shift amount in the sub-scanning direction is Dd.
e, distance D between assumed dot position and actual position
c can be determined by the following equation.

Dc = (Dd ² + De ² ) ^1/2 (5)

In such an embodiment, not only the deviation of the dot formation position in the main scanning direction but also the deviation of the dot formation position in the sub-scanning direction can be considered. However, even when actually causing the printer to form dots and measuring the dot formation positions to evaluate the amount of deviation, only one of the deviations in the main scanning direction or the sub-scanning direction can be used as a reference.

E. Modifications: The present invention is not limited to the above-described examples and embodiments, and can be carried out in various modes without departing from the gist thereof. For example, the following modifications are also possible. is there.

E1. Modified Example 1: In the first and third embodiments, the regular feeding of three dots is performed in the first sub-scanning mode, and two dots, three dots, and two dots are performed in the first sub-scanning mode of the second embodiment. An irregular feeding of dots, two dots, one dot, and two dots was performed. However, the feed of the upper end process and the lower end process is not limited to this, and other regular feeds or irregular feeds may be performed according to the number of nozzles in the nozzle row and the nozzle pitch. That is, it is sufficient that the maximum sub-scan feed amount is smaller than the maximum sub-scan feed amount in the intermediate processing. However, the smaller the feed amount of the sub-scan feed in the upper end process, the more the nozzle on the downstream side in the sub-scan direction can record the upper end of the printing paper. Therefore, the downstream groove can be made narrower, and the upper surface of the platen supporting the printing paper can be made wider. Similarly, as the feed amount of the sub-scan feed in the lower end process is smaller, the upper end of the printing paper can be recorded by the nozzle on the more upstream side. for that reason,
The upstream groove can be made narrower, and the upper surface of the central portion of the platen that supports the printing paper can be made wider.

In the above-described embodiment, the feed in the first sub-scanning mode and the feed in the third sub-scanning mode are the same, but they need not always be the same. For example, in the printer of the second embodiment, the feed in the first sub-scan mode is an irregular feed of 2 dots, 3 dots, 2 dots, 2 dots, 1 dot, and 2 dots, and the feed in the third sub-scan mode May be an irregular feed of 2 dots, 1 dot, 2 dots, 3 dots, 2 dots, and 2 dots. And, as in the first embodiment and the third embodiment,
It is not necessary to perform regular feeding through printing from upper end processing to lower end processing, and it is not necessary to perform irregular feeding through printing from upper end processing to lower end processing as in the second embodiment. The feed in the first sub-scan mode and the feed in the third sub-scan mode may be regular feed, and the second sub-scan mode may be irregular feed. That is, it is sufficient if the maximum sub-scan feed amount of the first sub-scan mode and the third sub-scan mode is smaller than the maximum sub-scan feed amount of the second sub-scan mode. .

E2. Modification 2: The present invention is applicable not only to color printing but also to monochrome printing. In addition, the present invention can be applied not only to an ink jet printer but also to a dot recording apparatus that generally performs recording on the surface of a recording medium using a recording head having a plurality of dot forming element arrays. Here, the “dot forming element” means a component for forming dots, such as an ink nozzle in an ink jet printer.

E3. Modification 3 In the above embodiment, a part of the configuration realized by hardware may be replaced by software, and conversely, a part of the configuration realized by software may be replaced by hardware. You may. For example, the CPU 41
A part of the functions shown in FIG. 3 may be executed by the host computer 90.

A computer program for realizing such functions is provided in a form recorded on a computer-readable recording medium such as a floppy disk or a CD-ROM. The host computer 90 reads the computer program from the recording medium and transfers it to an internal storage device or an external storage device. Alternatively, from the program supply device to the host computer 90 via a communication path.
May be supplied with a computer program. When implementing the functions of a computer program,
A computer program stored in the internal storage device is executed by the microprocessor of the host computer 90. Further, the host computer 90 may directly execute the computer program recorded on the recording medium.

In this specification, the host computer 90 is a concept including a hardware device and an operation system, and means a hardware device that operates under the control of the operation system. The computer program is executed by such a host computer 9.
0 implements the functions of the above-described units. Some of the functions described above may be realized by an operation system instead of the application program.

In the present invention, the “computer-readable recording medium” is not limited to a portable recording medium such as a flexible disk or a CD-ROM, but may be an internal storage such as various RAMs and ROMs. It also includes a device and an external storage device fixed to the computer such as a hard disk.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing changes in nozzles used on a print head of an ink jet printer according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a software configuration of the printing apparatus.

FIG. 3 is an explanatory diagram illustrating a schematic configuration of a printer 22.

FIG. 4 is an explanatory diagram illustrating an example of an arrangement of inkjet nozzles in a print head.

FIG. 5 is a plan view showing the periphery of a platen 26;

FIG. 6 is a plan view showing the relationship between image data D and printing paper P.

FIG. 7 is an explanatory diagram showing how each raster is recorded by which nozzle near an upper end (front end) of a printing sheet.

FIG. 8 is an explanatory diagram showing how each raster is recorded by which nozzle in upper end processing, upper end shift processing, and intermediate processing.

FIG. 9 is a side view showing the relationship between the print head and the printing paper P at the start of printing.

FIG. 10 is an explanatory diagram showing how each raster is recorded by which nozzle in the intermediate processing and the lower end shift processing.

FIG. 11 is an explanatory diagram showing how each raster is recorded by which nozzle in the intermediate processing, the lower end shift processing, and the lower end processing.

FIG. 12 is an explanatory diagram showing how each raster is recorded by which nozzle in the lower end process.

FIG. 13 is a plan view showing the relationship between the upstream groove 26f and the printing paper P when printing the lower end Pr of the printing paper P.

FIG. 14 is a side view showing the relationship between the print head and the printing paper P when printing the lowermost end of the printing paper.

FIG. 15 is a side view showing a relationship between a print head 28a, an upstream groove 26fa, and a downstream groove 26ra in the second embodiment.

FIG. 16 is an explanatory diagram showing how each raster is recorded by which nozzle in the upper end process of the second embodiment.

FIG. 17 is an explanatory diagram showing how each raster is recorded by which nozzle in the intermediate processing of the second embodiment.

FIG. 18 is an explanatory diagram showing how each raster is recorded by which nozzle in the intermediate processing, lower end shift processing, and lower end processing of the second embodiment.

FIG. 19 is an explanatory diagram showing changes in nozzles used on a print head in a third embodiment.

FIG. 20 is an explanatory diagram showing how each raster is recorded by which nozzle near the upper end (leading edge) of printing paper.

FIG. 21 is an explanatory diagram showing how each raster is recorded by which nozzle in the upper end processing, the upper end shift processing, and the intermediate processing.

FIG. 22 is an explanatory diagram showing how each raster is recorded by which nozzle in the lower end shift processing and the lower end processing.

FIG. 23 is an explanatory diagram showing how each raster is recorded by which nozzle in the lower end shift processing and the lower end processing.

FIG. 24 is a graph showing a difference in performance of each nozzle arranged in the sub-scanning direction.

FIG. 25 is an explanatory view showing the principle of the diaphragm inspection method.

FIG. 26 is an explanatory diagram showing a relationship between a position of a nozzle that discharges an ink droplet and a landing position of the ink droplet.

FIG. 27 is a side view showing the periphery of a print head of a conventional printer.

[Explanation of symbols]

12 Scanner 13 Mouse 21 CRT 22 Printer 23 Paper feed motor 24 Carriage motor 25a, 25b Upstream paper feed roller 25c, 25d Downstream paper feed roller 25p, 25q Upstream paper feed roller 25r 25s downstream paper feed roller 26, 26o platen 26c, 26ca central support 26f, 26fa upstream groove 26r, 26ra downstream groove 26sf upstream support 26sr downstream support 27f, 27r absorption Member 28, 28a, 28o Print head 31 Carriage 32 Operation panel 34 Sliding shaft 36 Drive belt 38 Pulley 39 Position detection sensor 40 Control circuit 41 CPU 41p Top printing section 41q Top printing Unit 41r: Intermediate printing unit 41s: Lower end transition printing unit 41t: Lower end mark Unit 42 PROM 43 RAM 44 Driving buffer 45 PC interface 52 Inspection unit 52 a Diaphragm 52 b Microphone 61 to 66 Ink ejection head 71 Black ink cartridge 72 Color ink cartridge 80 Ink Passageway 90 Host computer 91 Video driver 95 Application program 96 Printer driver 97 Resolution conversion module 98 Color correction module 99 Halftone module 100 Raster A A Arrow D Image data DT Dot forming pattern table Dm Difference between the position of the nozzle at the time of ejection of the ink droplet and the landing position of the ink droplet Ip: Ink droplet Iw: Weight of ink droplet LUT: Color correction table Nf, Nfa: First nozzle group Nh, Nha: Second Chirp group Ni, Nia Third nozzle group Nr, Nra Fourth nozzle group ORG Original color image data P Printing paper PD Printing data PE Piezoelectric element Pf Upper end Pr Lower end R26 Central support 26c Vk: Ink droplet ejection speed (flying speed) Vs: Main scanning speed k: Nozzle pitch n: Nozzle

Claims (26)

[Claims] 1. A dot recording apparatus for recording dots on the surface of a print medium using a dot recording head provided with a dot forming element group including a plurality of dot forming elements for discharging ink droplets, A main scanning drive unit that performs main scanning by driving at least one of a recording head and the print medium; and drives at least a part of the plurality of dot forming elements to form dots during the main scanning. A head driving unit to be provided, extending in the main scanning direction so as to face the plurality of dot forming elements in at least a part of the main scanning path, and facing the print medium to the dot recording head. A sub-scanning drive unit that performs sub-scanning by driving the print medium in a direction intersecting with the main scanning direction during the main scanning, A control unit for controlling a unit, wherein the platen is located in a position facing a first partial dot forming element group including a part of the plurality of dot forming elements in the main scanning direction. A first support portion that is provided to extend and supports the print medium; and a second support portion that is provided downstream of the first partial dot forming element group in the sub-scanning direction among the plurality of dot forming elements. A first groove extending in the main scanning direction at a position facing the partial dot forming element group; and a sub-scanning direction of the plurality of dot forming elements that is more subordinate to the second partial dot forming element group. A second support portion that is provided to extend in the main scanning direction at a position facing a third partial dot forming element group provided on the downstream side and supports the print medium; and Previous A second groove portion extending in the main scanning direction at a position facing the fourth partial dot forming element group provided downstream of the third partial dot forming element group in the sub-scanning direction; When the surface portion of the print medium is divided into an upper end portion including an upper end, an upper end transition portion, an intermediate portion, a lower end transition portion, and a lower end portion including a lower end in order from the top, the control is performed. The unit does not use the first to third partial dot forming element groups but uses the fourth partial dot forming element group to perform the first
In the sub-scanning mode, an upper end printing unit that forms dots at the upper end, and using the first to fourth partial dot forming element groups, the first sub-scanning mode uses the upper end transition unit. The maximum feed amount of the sub-scan is the maximum feed amount of the sub-scan in the first sub-scan mode by using the upper end shift printing unit for forming dots and the first to fourth partial dot forming element groups. An intermediate printing section for forming dots in the intermediate section in a second sub-scanning mode larger than the amount,
Dot recording device comprising: 2. The dot recording apparatus according to claim 1, wherein the upper end printing unit is configured such that the printing medium is supported by the platen, and that an upper end of the printing medium is above an opening of the second groove. A dot recording device that forms a dot on the upper end at one time. 3. The dot recording apparatus according to claim 1, wherein the control unit further includes the second to fourth partial dot forming elements without using the first partial dot forming element group. Using a group, in a third sub-scan mode in which the maximum feed amount of the sub-scan is smaller than the maximum feed amount of the sub-scan in the second sub-scan mode,
A lower end transition printing unit that forms dots in the lower end transition unit, and using the second partial dot forming element group without using the first, third, and fourth partial dot forming element groups, A dot printing device comprising: a lower end printing unit that forms dots at the lower end in the third sub-scanning mode. 4. The dot recording apparatus according to claim 3, wherein the nozzles of the second partial dot forming element group include the first partial dot forming element group.
A dot recording apparatus, wherein the average deviation amount of the dot formation positions on the print medium is smaller than the nozzles of the partial dot formation element group. 5. The dot recording apparatus according to claim 3, wherein the lower end printing section is configured such that the print medium is supported by the platen, and a lower end of the print medium is above an opening of the first groove. A dot recording device for forming dots at the lower end at one time. 6. A dot recording apparatus for recording dots on the surface of a print medium using a dot recording head provided with a dot forming element group composed of a plurality of dot forming elements for discharging ink droplets, A main scanning drive unit that performs main scanning by driving at least one of a recording head and the print medium; and drives at least a part of the plurality of dot forming elements to form dots during the main scanning. A head drive unit to be provided, provided to extend in the main scanning direction so as to face the plurality of dot forming elements in at least a part of the main scanning path, and to face the print medium to the dot recording head. A sub-scanning drive unit that performs sub-scanning by driving the print medium in a direction intersecting with the main scanning direction during the main scanning, A control unit for controlling a unit, wherein the platen is located in a position facing a first partial dot forming element group including a part of the plurality of dot forming elements in the main scanning direction. A first support portion that is provided to extend and supports the print medium; and a second support portion that is provided downstream of the first partial dot forming element group in the sub-scanning direction among the plurality of dot forming elements. A first groove extending in the main scanning direction at a position facing the partial dot forming element group; and a sub-scanning direction of the plurality of dot forming elements that is more subordinate to the second partial dot forming element group. A second support portion that is provided to extend in the main scanning direction at a position facing a third partial dot forming element group provided on the downstream side and supports the print medium; and Previous A second groove portion extending in the main scanning direction at a position facing the fourth partial dot forming element group provided downstream of the third partial dot forming element group in the sub-scanning direction; Extending in the main scanning direction to a position facing a fifth partial dot forming element group provided downstream of the fourth partial dot forming element group in the sub-scanning direction among the plurality of dot forming elements. And a third support portion for supporting the print medium. The top surface portion of the print medium, in order from the top, an upper end portion including an upper end, an upper end transition portion, an intermediate portion, and a lower end transition portion. When the control unit is divided into a lower end portion including a lower end, the control unit does not use the first, second, third, and fifth partial dot forming element groups, and controls the fourth partial dot forming element. Using the group, in the first sub-scan mode, the upper end An upper end printing unit for forming dots in the unit, and an upper end transition printing unit for forming dots in the upper end transition unit in the first sub-scanning mode using the first to fourth partial dot forming element groups And using the first to fifth partial dot forming element groups, the second sub-scanner having a maximum sub-scan feed amount larger than the maximum sub-scan feed amount in the first sub-scan mode. An intermediate printing unit that forms dots in the intermediate unit in a scanning mode;
Dot recording device comprising: 7. The dot recording apparatus according to claim 6, wherein the nozzles of the fourth partial dot forming element group are arranged in the fifth partial dot forming element group.
A dot recording apparatus, wherein the average deviation amount of the dot formation positions on the print medium is smaller than the nozzles of the partial dot formation element group. 8. The dot recording apparatus according to claim 6, wherein the upper end printing unit is configured such that the print medium is supported by the platen, and the upper end of the print medium is above the opening of the second groove. A dot recording device that forms a dot on the upper end at one time. 9. The dot recording apparatus according to claim 6, wherein the control unit further comprises the second to fifth partial dot forming elements without using the first partial dot forming element group. Using a group, in a third sub-scan mode in which the maximum feed amount of the sub-scan is smaller than the maximum feed amount of the sub-scan in the second sub-scan mode,
A lower end transition printing unit that forms dots at the lower end transition unit; and the second partial dot forming element group is used without using the first, third, fourth, and fifth partial dot forming element groups. And a lower end printing unit for forming dots at the lower end in the third sub-scanning mode. 10. The dot recording apparatus according to claim 9, wherein the nozzles of the second partial dot forming element group include the first partial dot forming element group.
A dot recording apparatus, wherein the average deviation amount of the dot formation positions on the print medium is smaller than the nozzles of the partial dot formation element group. 11. The dot recording apparatus according to claim 9, wherein the lower end printing section is configured such that the print medium is supported by the platen, and a lower end of the print medium is above an opening of the first groove. A dot recording device for forming dots at the lower end at one time. 12. A dot recording apparatus for recording dots on a surface of a printing medium supported by a platen using a dot recording head provided with a dot forming element group including a plurality of dot forming elements for discharging ink droplets. While driving at least one of the dot recording head and the printing medium to perform main scanning, at least a part of the plurality of dot forming elements is driven to form dots, and between the main scanning. A dot recording method for performing sub-scanning by driving the print medium in a direction intersecting with the main scanning direction, wherein the platen is a first part including a part of the plurality of dot-forming elements. A first support portion that is provided at a position facing the dot forming element group and extends in the main scanning direction and supports the print medium; A first groove portion extending in the main scanning direction at a position facing a second partial dot forming element group provided downstream of the first partial dot forming element group in the sub-scanning direction; And extending in the main scanning direction to a position facing a third partial dot forming element group provided downstream of the second partial dot forming element group in the sub-scanning direction among the plurality of dot forming elements. A second support portion for supporting the print medium, and a fourth portion of the plurality of dot forming elements provided downstream of the third partial dot forming element group in the sub-scanning direction. At a position facing the dot forming element group, a second groove portion is provided extending in the main scanning direction, and a top surface portion of the printing medium, in order from the top, an upper end portion including an upper end, Top transition, middle, bottom When the dot recording method is divided into a transition portion and a lower end portion including a lower end, the dot recording method includes: (a) the fourth partial dot forming element without using the first to third partial dot forming element groups; Forming dots at the upper end in a first sub-scanning mode using a group; and (b) using the first to fourth partial dot forming element groups to form the first sub-dots. Forming a dot in the upper end transition portion in the scanning mode; and (c) using the first to fourth partial dot forming element groups to adjust the maximum feed amount of the sub-scan to the first sub-dot. A second feed amount larger than the maximum feed amount of the sub-scan in the scan mode;
Forming a dot in the intermediate portion in the sub-scanning mode. 13. The dot recording method according to claim 12, wherein in the step (a), the print medium is supported by the platen, and an upper end of the print medium is above an opening of the second groove. When in
A dot recording method, comprising a step of forming a dot on the upper end. 14. The dot recording method according to claim 12, further comprising: (d) using the second to fourth partial dot forming element groups without using the first partial dot forming element group. Using the maximum feed amount of the sub-scan
Forming a dot at the lower end transition portion in a third sub-scanning mode smaller than the maximum sub-scanning feed amount in the sub-scanning mode of the sub-scanning mode; and (e) forming the first, third, and fourth partial dots Forming a dot at the lower end in the third sub-scanning mode using the second partial dot forming element group without using the forming element group. 15. The dot recording method according to claim 14, wherein the nozzles of the second partial dot forming element group are arranged in the first partial dot forming element group.
The dot recording method, wherein the average deviation amount of the dot formation positions on the print medium is smaller than the nozzles of the partial dot formation element group. 16. The dot recording method according to claim 14, wherein in the step (e), the print medium is supported by the platen, and a lower end of the print medium is above an opening of the first groove. When in
A dot recording method, comprising a step of forming a dot at the lower end. 17. A dot recording apparatus for recording dots on the surface of a printing medium supported by a platen using a dot recording head provided with a dot forming element group composed of a plurality of dot forming elements for discharging ink droplets. While driving at least one of the dot recording head and the printing medium to perform main scanning, at least a part of the plurality of dot forming elements is driven to form dots, and between the main scanning. A dot recording method for performing sub-scanning by driving the print medium in a direction intersecting with the main scanning direction, wherein the platen is a first part including a part of the plurality of dot-forming elements. A first support portion that is provided at a position facing the dot forming element group and extends in the main scanning direction and supports the print medium; A first groove portion extending in the main scanning direction at a position facing a second partial dot forming element group provided downstream of the first partial dot forming element group in the sub-scanning direction; And extending in the main scanning direction to a position facing a third partial dot forming element group provided downstream of the second partial dot forming element group in the sub-scanning direction among the plurality of dot forming elements. A second support portion for supporting the print medium, and a fourth portion of the plurality of dot forming elements provided downstream of the third partial dot forming element group in the sub-scanning direction. A second groove portion extending in the main scanning direction at a position facing the dot forming element group; and a second groove portion in the sub-scanning direction more than the fourth partial dot forming element group among the plurality of dot forming elements. Installed downstream A third support portion provided in the main scanning direction to extend in the main scanning direction at a position facing the fifth partial dot forming element group to be supported, and supporting the print medium. , In order from the top, an upper end portion including an upper end, an upper end transition portion, an intermediate portion, a lower end transition portion, and a lower end portion including a lower end, the dot recording method includes: (a) the first, second, Forming a dot at the upper end in the first sub-scanning mode using the fourth partial dot forming element group without using the third and fifth partial dot forming element groups; (B)
Forming a dot at the upper end transition portion in the first sub-scanning mode using the first to fourth partial dot forming element groups; and (c) forming the first to fifth partial dots. Using the forming element group, in the second sub-scanning mode in which the maximum sub-scanning feed amount of the first sub-scanning mode is larger than the maximum sub-scanning feed amount of the first sub-scanning mode, dots are formed in the intermediate portion. A dot recording method. 18. The dot recording method according to claim 17, wherein the nozzles of the fourth partial dot forming element group are arranged in the fifth partial dot forming element group.
The dot recording method, wherein the average deviation amount of the dot formation positions on the print medium is smaller than the nozzles of the partial dot formation element group. 19. The dot recording method according to claim 17, wherein in the step (a), the print medium is supported by the platen, and an upper end of the print medium is above an opening of the second groove. When in
A dot recording method, comprising a step of forming a dot on the upper end. 20. The dot recording method according to claim 17, further comprising: (d) using the second to fifth partial dot forming element groups without using the first partial dot forming element group. Using the maximum feed amount of the sub-scan
Forming a dot at the lower end transition portion in a third sub-scanning mode smaller than the maximum amount of sub-scanning in the sub-scanning mode; and (e) the first, third, fourth and fifth steps Without using the partial dot forming element group of the above, using the second partial dot forming element group, in the third sub-scanning mode,
Forming a dot at the lower end. 21. The dot recording method according to claim 20, wherein the nozzles of the second partial dot forming element group include the first partial dot forming element group.
The dot recording method, wherein the average deviation amount of the dot formation positions on the print medium is smaller than the nozzles of the partial dot formation element group. 22. The dot recording method according to claim 20, wherein in the step (e), the print medium is supported by the platen, and a lower end of the print medium is above an opening of the first groove. When in
A dot recording method, comprising a step of forming a dot at the lower end. 23. A dot recording apparatus for recording dots on the surface of a printing medium supported by a platen using a dot recording head provided with a dot forming element group composed of a plurality of dot forming elements for discharging ink droplets. A computer comprising: driving at least one of the dot recording head and the print medium to perform main scanning, and driving at least a part of the plurality of dot forming elements to form dots; A computer-readable recording medium that records a computer program for driving the printing medium in a direction intersecting with the main scanning direction to perform sub-scanning during main scanning, wherein the platen includes Extends in the main scanning direction to a position facing a first partial dot forming element group including a part of the dot forming elements. A first support portion for supporting the print medium, and a second partial dot provided downstream of the first partial dot forming element group in the sub-scanning direction among the plurality of dot forming elements. A first groove portion extending in the main scanning direction at a position facing the forming element group; and a downstream in the sub-scanning direction from the second partial dot forming element group among the plurality of dot forming elements. A second support portion provided in the main scanning direction to extend in the main scanning direction at a position facing a third partial dot forming element group provided on the side, and supporting the print medium; A second groove portion extending in the main scanning direction at a position facing a fourth partial dot forming element group provided downstream of the third partial dot forming element group in the sub-scanning direction. Have When the surface portion of the print medium is divided into an upper end portion including an upper end, an upper end transition portion, an intermediate portion, a lower end transition portion, and a lower end portion including a lower end in order from the top, the first to third partial dots Using the fourth partial dot forming element group without using the forming element group, the first
In the sub-scanning mode, using the function of forming dots at the upper end portion, and using the first to fourth partial dot forming element groups, to form dots at the upper end transition portion in the first sub-scanning mode Forming the first sub-scan mode and the first to fourth partial dot forming element groups, wherein the maximum sub-scan feed amount is larger than the maximum sub-scan feed amount in the first sub-scan mode. 2. A computer-readable recording medium recording a computer program for causing the computer to realize the function of forming dots in the intermediate portion in the sub-scanning mode of 2. 24. The recording medium according to claim 23, wherein:
Further, without using the first partial dot forming element group, by using the second to fourth partial dot forming element groups, the maximum feed amount of the sub-scanning can be reduced by the second sub-scanning mode. In the third sub-scanning mode smaller than the maximum feed amount of the sub-scanning,
A function of forming a dot at the lower end transition portion; and a third method using the second partial dot forming element group without using the first, third, and fourth partial dot forming element groups. A computer-readable recording medium which records a computer program for causing the computer to realize the function of forming dots at the lower end in the sub-scanning mode. 25. A dot recording apparatus for recording dots on a surface of a printing medium supported by a platen using a dot recording head provided with a dot forming element group including a plurality of dot forming elements for discharging ink droplets. A computer comprising: driving at least one of the dot recording head and the print medium to perform main scanning, and driving at least a part of the plurality of dot forming elements to form dots; A computer-readable recording medium that records a computer program for driving the printing medium in a direction intersecting with the main scanning direction to perform sub-scanning during main scanning, wherein the platen includes Extends in the main scanning direction to a position facing a first partial dot forming element group including a part of the dot forming elements. A first support portion for supporting the print medium, and a second partial dot provided downstream of the first partial dot forming element group in the sub-scanning direction among the plurality of dot forming elements. A first groove portion extending in the main scanning direction at a position facing the forming element group; and a downstream in the sub-scanning direction from the second partial dot forming element group among the plurality of dot forming elements. A second support portion provided in the main scanning direction to extend in the main scanning direction at a position facing a third partial dot forming element group provided on the side, and supporting the print medium; A second groove portion extending in the main scanning direction at a position facing a fourth partial dot forming element group provided downstream of the third partial dot forming element group in the sub-scanning direction; Multiple do And extending in the main scanning direction at a position facing a fifth partial dot forming element group provided downstream of the fourth partial dot forming element group in the sub-scanning direction from the fourth partial dot forming element group, A third support portion for supporting the print medium, wherein the surface portion of the print medium includes, in order from the top, an upper end portion including an upper end, an upper end transition portion, an intermediate portion, a lower end transition portion, and a lower end. When divided into the lower end portion, the first, second, third, and fifth partial dot forming element groups are not used, and the first partial dot forming element group is used. Using the function of forming dots at the upper end in the sub-scanning mode and forming the dots at the upper end transition in the first sub-scanning mode using the first to fourth partial dot forming element groups And the first to fifth partial dot forming element groups A function of forming dots in the intermediate portion in a second sub-scan mode in which the maximum feed amount of the sub-scan is larger than the maximum feed amount of the sub-scan in the first sub-scan mode. And a computer-readable recording medium recording a computer program for causing the computer to realize the above. 26. The recording medium according to claim 25, wherein:
Further, without using the first partial dot forming element group, using the second to fifth partial dot forming element groups, the maximum feed amount of the sub-scanning is set in the second sub-scanning mode. In the third sub-scanning mode smaller than the maximum feed amount of the sub-scanning,
A function of forming dots in the lower end transition portion, and using the second partial dot forming element group without using the first, third, fourth, and fifth partial dot forming element groups, A computer-readable recording medium recording a computer program for causing the computer to implement the function of forming dots at the lower end in the third sub-scanning mode.