JPH026141A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To use ink discharged in the same line by scanning in the first direction for the first time as one color section, and to record an excellent picture image by displacing each recording head in the second direction only by at least recording width and arranging the recording heads. CONSTITUTION:Each color head 209Y, 209M, 209C and 209K respectively has 256 discharge nozzles at 63.5mum pitches. The heads of each color are arranged while being displaced at every 63.5mum X 256 = 16.256mm in the cross scanning direction and at every fixed quantity (d) in the main scanning direction. Consequently, since the magenta head 209M is arranged in the backward direction only by the distance (d) in the scanning direction (the P direction) from the yellow head 209Y, the signal M of magenta is delayed by a buffer 1M composed of a flip-flop, etc., in order to compensate the backward arrangement. As a result, ink only by one color section is discharged to one line width on a material to be recorded on one-time scanning in the P direction, thus sufficiently fixing ink until ink is discharged in the next main scanning. Accordingly, a picture image is not bled and a feed roller 105 is not contaminated.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to an inkjet recording device, and particularly to an inkjet recording device that is suitable for recording materials with poor fixing properties, such as transparent films for overhead projectors (OIIP). This allows image recording to be performed.

[Prior Art] Inkjet recording devices have features such as stable image quality because of direct recording and easy miniaturization. Interest is increasing as a recording technology that can meet the increasing demand for output.

FIG. 6 is a perspective view of a conventional inkjet recording apparatus.

In the figure, a recording material 101 has its recording surface regulated by a conveyance roller 104 from a position where it is held between conveyance rollers 102 and 103, and then is conveyed in the Q direction while being held between feeding rollers 105 and 106. A guide rail 107 is arranged in the width direction of this recording material 101, and a head unit 109 mounted on a carriage 108 is scanned along the guide rail 107 in the P direction by a drive wire 110.

The carriage 109 has heads 109Y, corresponding to each color of yellow, magenta, cyan, and black, for example.
109M, 109G, and 1098k are installed, and each color ink tank (not shown) is connected to each head.

While being scanned in the P direction, the head unit 109 ejects ink droplets in response to the supply of image signals, thereby recording a color image. When image recording for one line is completed, the recording material 101 is transferred to the head unit 10.
It is conveyed in the Q direction by a recording width of 9, and then image recording is performed again by the head unit 109. By repeating this operation, an image is formed on the recording material 101.

FIG. 7 is a diagram when the head unit 109 is viewed from the recording material side. 4 heads 109Y, 109M.

109C and 109Bk each have 256 nozzles, and these heads are arranged side by side on the carriage 108 to form a head unit 109. With this configuration and arrangement of the head, recording for four colors can be completed in one scan, and a full-color image can be easily obtained.

[Problem to be solved by the invention J However, with such a configuration, ink for four colors is ejected in one scan, so when recording an image on a recording material with poor absorbency, There have been problems such as the recording material not being able to fully absorb the ink, causing the image to bleed, and the ink that has not been absorbed to be attached to the feeding roller 105. It is well known that there is a high demand for OHP recording materials, especially for color image recording, but since OHP recording materials have considerably lower absorbency than ordinary recording paper, such The problem was noticeable.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an inkjet recording apparatus that solves these problems and is capable of recording good images even when recording materials with poor absorbency or fixing properties are used.

[Means for Solving the Problems] In order to achieve such an object, the present invention includes a plurality of print heads in which nozzle groups for ejecting recording ink are arranged, and a plurality of print heads in which the plurality of print heads are arranged in an arrangement during printing. In an inkjet recording apparatus, the inkjet recording apparatus includes a means for scanning in a first direction different from the first direction, and a means for relatively scanning the recording material and the plurality of recording heads in a second direction different from the first direction. The printing head is characterized in that the printing heads are respectively shifted in the second direction by at least the width in the second direction printed during one scan in the first direction.

[Function] According to the present invention, by arranging each recording head so as to be shifted in the second direction by at least the recording width, one
In each scan in the first direction, ink of one color is ejected onto the same line. As a result, even if a recording material with poor absorbency or fixing properties, such as 01 (P liquid recording material), is used, there is an interval between the scan diameter in the first direction and the next scan, resulting in a good image quality. An image will be obtained.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram of a head unit 209 according to an embodiment of the inkjet recording apparatus of the present invention, viewed from the recording material 101 side. Each color head 209Y, 209M, 209C, and 209Bk has a pitch of 63.5 μm and a pitch of 25
It is a multi-head with six ejection nozzles for, for example, yellow, magenta, cyan, and black ink. In this example, each color head is 63.5 μm x 256 = 16.256 mm in the sub-scanning direction.
, and are arranged so as to be shifted by a predetermined amount d in the main scanning direction.

FIG. 2 shows an example of the configuration of a signal supply control circuit for supplying image signals to the head unit 209 shown in FIG.

Here, the yellow image signal Y is sent to the yellow head 109Y without delay and recorded. 2, 3 and 4 are heads 209M, 209G and 2098 respectively
The magenta image signal M, the cyan image signal C, and the black image signal BK are applied to the image signal Y for 1 line and 2 lines, respectively, corresponding to the arrangement position in the sub-scanning direction (Q direction). This is a buffer that delays by one line and three lines. IO is a control unit that controls the operations of the buffers 2 to 4, and can be composed of a CPU that executes processing procedures described later with reference to FIG. 4, and a ROM that stores programs corresponding to the processing procedures.

The magenta signal M indicates that the magenta head 209M is 7J away from the yellow head 209Y in the main scanning direction (P direction).
d, so in order to compensate for this, a buffer 1M made up of flip-flops, etc.
will be delayed. For example, if d = 10mm, 16d
When recording at a density of at/mm, the buffer IM
It is assumed that a delay of 160 dots is performed.

Similarly, buffers Ic and IBk each output 32 times the cyan image signal C for the yellow image signal Y.
0 dot and black image signal Bk to 480 d
This is to delay by ot.

FIG. 3 shows an example of the configuration of buffers 2 to 4 in FIG. 2. In the figure, 21, 22, 31-33 and 41-
44 is an RA with a storage capacity of one line of image data.
M, 25.35 and 45 are RAM2, respectively
1.

22, RAM31-33. This is a selector for switching data output paths from the RAMs 41 to 44.

The control unit IO controls the write/read state settings of each RAM and the switching settings of each selector.

FIG. 4 shows an example of a setting processing procedure executed by the control unit IO when recording an image. Further, FIGS. 5(8) to 5(D) show sequential recording operations according to this example.

When starting recording, first in step S1 in FIG.
RAMs 21, 31 and 41 are set to write state.

In this state, the first line image signal Yl.

Ml, CI and Bkl are supplied to the head unit 20.
9 is scanned in the P direction, the yellow signal Y1 of the first line is recorded by the head 209Y (FIG. 5(A)), and the other signals Ml, C1 and Bkl are recorded.
are stored in RAMs 21, 31 and 41, respectively.

When processing the second line, RA is used in step S3.
M22.32 and 42 are set to write state, and
RAM21 is set to read state and selector 25 is set to RAM2.
Switch to select the output from 1. In this state, the recording material lot is moved by a predetermined amount (+6.2sa) in the Q direction.
mm) tlt and the second line image signal is supplied, the head 209Y records yellow image data Y2 on the second line, and the yellow image data Y2 is recorded on the first line facing the head 209M from the RAM 21. The old magenta image data is recorded (FIG. 5(B)).

Also, each image data M2 of the second line. C2 and Bk
2 is 1. (Stored in 8M22.32 and 42.

When processing the third line, the RAM
21, 33, and 43 are in the write state, and the RAM
22 and 31 are placed in a read state, and selectors 25 and 35 are switched to select I outputs from RAMs 22 and 31, respectively. In this state, the recording material 10
1 is conveyed by a predetermined amount in the Q direction, the image signal of the third line is supplied, and the head unit 209 scans in the P direction, and the head 209Y records yellow image data Y3 on the third line. , head 209M
The magenta image data M2 read from the RAM 22 is recorded on the second line facing the head 209C, and the cyan image data C1 read from the RAM 31 is recorded on the first line facing the head 209C (see FIG. )). Also, the third
Each line image data M3. C3 and Bk3 are expanded to RAMs 21.33 and 43, respectively.

When processing the fourth line, RA
M22.31 and 44 in writing state, RAM21.3
2 and 41 are placed in a read state, and appropriate switching settings of selectors 25, 35 and 45 are performed. Then, the recording material 101 is conveyed by a predetermined amount in the Q direction, and the head unit 20
9 is scanned in the P direction, the head 209Y scans the fourth
Yellow image data Y4 is recorded on the line, and the heads 209M, 209[: and 209
8k, image data M3. C2 and Bkl are recorded (FIG. 5(D)). That is, a full color image of Y1+M1+CI+Bkl is now formed on the first line. Also, the fourth line image data M4. C4 and Bk4 are RAM2, respectively.
2.31 and 44.

Thereafter, in the same manner, step S12. . . ., image formation is performed by performing the process of S33 and then returning to step Sll, that is, by cyclically bringing RAk+21.22.31 to 33 and 41 to 44 into the write/read state. Just go.

In this way, during one scan in the P direction, only one color of ink is ejected for one line width on the recording material 101, so that the ink is sufficiently fixed before being ejected in the next main scan. do. Therefore, even when a recording material with poor absorbency, such as a 011P recording material, is used, the image does not bleed or the feeding roller 105 is not contaminated.

In addition, the above head arrangement and RAM writing/
It is clear that by performing read control, the recording speed does not decrease.

In the embodiment, color images are formed using four colors: yellow, magenta, cyan, and black. However, even if color images are formed using three colors: yellow, magenta, and cyan, the present invention is applicable. Needless to say, it is extremely effective and easy to apply.

Further, in the above-described embodiment, the sub-scanning is performed by conveying the recording material in the Q direction, but the recording material may be fixed and the head unit is caused to perform the sub-scanning.

Furthermore, on the upper side, each head is shifted in the sub-scanning direction by an amount (one line) corresponding to the nozzle arrangement range, and is spaced apart by a distance ad in the main scanning direction, but this configuration can be made in various ways. be able to. For example, each head may be arranged two lines apart and not biased in the main scanning direction, or the recording range in one main scanning may be less than or equal to the nozzle arrangement range, for example, one
/2, it may be shifted by that range in the sub-scanning direction.

In addition, the control unit 10 that performs the above control controls the recording material 101.
It may also be used as the main control section of the device that scans the carriage 108 and generates image signals Y, M, C, Bk, etc., or it may be a separate unit.

[Effects of the Invention] As explained above, according to the present invention, each color head is
The heads are arranged so that they are shifted by the recording width during each main scan, and the amount of ink ejected on the same line in one main scan is for one color. Even when a recording material with poor fixing properties was used, a good image without bleeding could be obtained.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of the configuration of a head unit applicable to the inkjet recording apparatus of the present invention, and FIG. 2 is a configuration of a signal supply control circuit for supplying image signals to the head unit shown in FIG. 1. A block diagram showing an example; FIG. 3 is a block diagram showing an example of the configuration of the main parts; FIG. 4 is a flowchart showing an example of a control procedure for the configuration shown in FIG. 3; FIGS. 5 (A) to (D) FIG. 6 is a perspective view showing a configuration example of a conventional inkjet recording apparatus, and FIG. 7 is a front view of a conventional head unit. 1M, IC, IBk, 2~4...Buffer, lO・
...Control unit, 21.22.31~33.41~44...IIAM
. 25.35.45... Selector, 101... Recording material, 108... Carriage, 109.209... Head unit, 109Y, l
09M, 109G, 1098, 209Y, 209M, 2
09 (:, 209BP...Main scanning direction, Q...Sub-scanning direction. ...head, Fig. 2 Fig. 1 Fig. 4 (A) (B) Y10M+ +CI +Bk1 YI+M +C+ Y+tJC10C2 Y2◆ M2 Y3+M3 Fig. 5+05 Fig. 6

Claims (1)

[Scope of Claims] 1) a plurality of recording heads in which nozzle groups for ejecting recording ink are arranged; and means for scanning the plurality of recording heads in a first direction different from the direction of the arrangement during recording; An inkjet recording apparatus comprising means for relatively scanning a recording material and the plurality of recording heads in a second direction different from the first direction, wherein the plurality of recording heads are scanned at least in the first direction. An inkjet recording apparatus characterized in that the inkjet recording apparatus is arranged so as to be shifted in the second direction by a width in the second direction recorded during one scan.