JP2003039684A - Inkjet recording device - Google Patents

Abstract

(57) [Summary] [Problem] To accurately grasp the positional relationship between print dot groups by a plurality of print head modules and electrically adjust the positional relationship, thereby facilitating automatic adjustment, and high-speed high-quality images. Provided is an ink jet recording apparatus capable of performing recording on a recording medium. A recording dot that is not ejected simultaneously from adjacent nozzles in a head module is used as a recording dot formed to detect a positional relationship of a head module in a recording medium movement direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet recording apparatus, and more particularly to an inkjet recording apparatus capable of recording a high quality image at high speed by a plurality of recording head modules.

[0002]

2. Description of the Related Art In a conventional serial scanning type ink jet recording apparatus for continuous paper, a recording head is moved (main scanning) while ejecting ink in a direction intersecting the continuous direction of the continuous paper, and a plurality of main scanning lines are provided. The belt-shaped image of one line is recorded, the recording paper is fed by a predetermined amount in the continuous direction of the continuous paper (sub-scanning), and then the belt-shaped image of the next row is main-scanned and recorded. An image is recorded by repeating the main scanning and the sub scanning. In such a serial scanning inkjet recording apparatus, in order to increase the recording speed, the number of main scanning lines of band-shaped recording that can be recorded per main scanning is increased, or a method in which short recording head modules are arranged and combined is adopted. Has been.

In a serial scanning type ink jet recording apparatus, as a method of arranging the recording head modules with high accuracy, as described in Japanese Patent Laid-Open No. 5-305734, the main scanning direction is a line perpendicular to the main scanning direction. After printing the minutes and measuring the distance between the line segments, the print data is adjusted by shifting the amount in the main scanning line direction. In the sub-scanning direction, a line segment perpendicular to the sub-scanning direction is printed, the distance between the line segments is measured, and then the mechanical positional relationship of the recording head module is adjusted by the amount of deviation in the sub-scanning direction.

Further, a high-speed ink jet recording apparatus uses a long line recording head in which nozzle holes for the number of scanning lines necessary for recording a continuous recording paper width are arranged.

As a method of realizing such a long recording head, there is a method of forming a large number of nozzles in a line at a time, but this method generally has a low manufacturing yield. This is because, if there is at least one nozzle having a variation in ink ejection characteristics among many nozzles, then the recording dots will cause deterioration in print quality. Therefore, as a method of realizing a long print head, there is a method of arranging and combining short print head modules with good manufacturing yield. That is, the recording dot groups recorded by the respective recording head modules are accurately combined, and recording is performed in the same manner as a long recording head in which a large number of nozzles are formed in a line at once.

In the case of this method, first, it is necessary to arrange a plurality of recording head modules accurately.

As a method of arranging the recording head modules with high accuracy, as disclosed in Japanese Patent Laid-Open No. 9-262992, a nozzle for recording a test pattern is used, or a part of the recording nozzle is used. Record the test pattern. Next, the positional relationship of the recording head module was obtained from the test recording pattern, and based on this, the positional relationship of the recording head module itself was adjusted using a mechanical adjustment mechanism. Further, in the scanning direction, the recording module can be adjusted by adjusting the head module itself using the same mechanical adjustment mechanism or by electrically adjusting the adjustment recording data. Was combined with means.

Further, as means for obtaining the print head positional relationship from the test print pattern, there is Japanese Patent Laid-Open No. 2000-1273.
As disclosed in Japanese Laid-Open Patent Publication No. 7, a plurality of patterns in which the positional relationship of the heads is shifted little by little using an adjusting mechanism is printed, and then the print density of the test recording pattern is detected by an optical sensor, and the head is determined from the print density obtained. The method of estimating the optimal positional relationship of the modules was used.

Further, in the ink jet recording head,
Crosstalk is a big problem. This crosstalk means that when another nozzle in the head module is driven at the same time as the target nozzle, the target nozzle is affected by solid vibration and liquid vibration from the other nozzle driven at the same time. . When this crosstalk occurs, the target nozzle may be affected by the ink ejection speed, the ejected ink amount, and even the ejection direction. If the number of nozzles driven simultaneously in the same head module increases, the crosstalk also increases.

[0010]

In such a conventional adjusting method, a nozzle for recording a test pattern is used,
Alternatively, in order to create a test pattern by using only a part of the recording nozzles and obtain the positional relationship of the recording head module, variations in the ink flight direction and velocity ink amount for each nozzle, and the effects of nozzle characteristic changes due to temperature changes, etc. Is difficult to avoid, and positional deviation occurs in the entire image, which deteriorates the image.

Further, since it is necessary to make mechanical adjustment, there is a problem that if an attempt is made to increase the adjustment accuracy, the adjusting mechanism becomes complicated and it is difficult to automate the adjustment.

Further, the conventional means for obtaining the recording head positional relationship from the test recording pattern prints the recording dots recorded from the respective head modules in the immediate vicinity or intentionally overlapping each other. Therefore, when measuring the print density, it is very difficult to avoid the effects of ink bleeding that changes depending on the printing atmosphere and recording medium, and the difference in density depending on the recording medium. It wasn't easy either.

Further, if the alignment is performed in the state where the crosstalk occurs, for example, when the printing density of a ruled line made up of a thin line is low and the ink bleeding is small, the influence of the crosstalk is small and the head module seam portion is small. Will reduce the print quality.

An object of the present invention is to accurately grasp the positional relationship of a group of recording dots by a plurality of recording head modules and to electrically adjust the positional relationship to facilitate automation of adjustment and to produce a high quality image at high speed. Another object of the present invention is to provide an inkjet recording device capable of recording.

[0015]

In order to achieve the above object, in an ink jet recording apparatus of the present invention, a plurality of nozzle holes for ejecting ink particles for forming an image on a recording medium are formed substantially linearly. In the ink jet recording apparatus having a unit for detecting and adjusting the positional relationship between a plurality of arranged recording head modules based on recording dots formed by the ink particles ejected from the head module, the recording medium moving direction As the recording dots formed to detect the positional relationship of the head module, recording dots that are not ejected simultaneously from the adjacent nozzles in the head module are used.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration example of a line scanning type ink jet recording apparatus used in the present invention. This line scanning type inkjet recording apparatus can perform recording by ejecting ink in response to an ink ejection input signal, and can control deflection of an ink flight trajectory in accordance with an input signal to a charge deflection electrode. Is possible.

When printing is started, the recording paper 100 is conveyed in the B direction at a constant speed. The signal processing unit 201 creates an ejection data signal 304 and charge deflection data signals 302 and 303 from the print data signal 301. The nozzle drive driver 204 creates a nozzle drive signal 308 from the ejection data signal 304 and applies it to the nozzle row 104. The charge deflection electrode drivers 202 and 203, which have received the corresponding charge deflection data signals 302 and 303, respectively, charge the charge deflection voltage 3 for generating a common charge electric field and a deflection electric field for each column.
It outputs 09 and 310. As a result, the ejection data signal 3
Ink droplets are ejected from the nozzle array 104 in accordance with 04. The ejected ink droplets are charged by a charging electric field, are deflected in the flight direction by a constant electric field, and land on a recording paper to obtain a recorded image. The head module is arranged so as to be inclined by an angle θ so that the droplets land on the recording paper lattice points.

In the head module adjustment mode, the signal processing unit 201 simultaneously outputs the optical sensor control signal 305 to control the optical sensor 105. The optical sensor 105 reads the recorded image and outputs an image read data signal 306 as digital data to the signal processing unit 201.
The signal processing unit 201 having received the image read data signal 306 calculates the position of each head module 101 from the image read data signal 306, and according to the result, the ejection data signal 304 and the charge deflection data signals 302 and 30.
Change 3.

The details of each section will be described below. Figure 2
Shows a cross section at CC ′ in FIG. 1. An outline of an ink droplet ejection method and a droplet deflection method will be described.
Reference numeral 401 is a piezoelectric element made of ceramics, 402 is a vibrating plate, 403 is a restrictor plate, 404 is a chamber plate, and 405 is an orifice plate. For example, the diaphragm 402, the restrictor plate 403, and the chamber plate 404 are made of stainless steel, and the orifice plate 405 is made of nickel. When the nozzle drive signal 308 is applied, the piezoelectric element 401 deforms, and pressure is applied to the ink via the vibration plate 402. The pressurized ink is ejected as an ink droplet 407 from the orifice 406. The ejected ink droplets are charged by the charge deflection electrodes 102 and 103 arranged in parallel with the nozzle row direction by an amount of electric charge corresponding to the applied electric field until just before being ejected from the orifice 406. The ejected and separated ink droplet 407 is deflected in the ejection direction by the electric field due to a constant deflection voltage by the charge deflection electrodes 102 and 103. As a result, the ink droplet landing position changes in the charging electrode direction as in D1 and D2 with respect to the ink flight direction E when the deflection is not performed. When the deflection voltage is shifted, it is possible to shift the entire landing position of the droplet by dD corresponding to the electric field due to the shift voltage.
As a result, the landing position of the droplet can be shifted in the direction perpendicular to the nozzle row arrangement direction A.

FIG. 3 shows an example in which the electric field and the nozzle drive signal based on the charge deflection voltage signal are simply shown. As an example, the case of deflecting in four directions is shown. The charge deflection electric field is periodic A
The electric field is the electric field due to the charging voltage of the C component and the electric field due to the deflection voltage of the DC component. The nozzle drive signal is
Since there is a delay from being applied to the piezoelectric element until the droplet is ejected, it is applied earlier by dT time so that the ink droplet can be appropriately charged. FIG. 4 shows a schematic diagram of the result of recording by applying each signal in this way. Chart paper 100 is B
Is moving in the direction. The droplet discharged at the timing T4 in FIG. 3 is largely deflected in the direction perpendicular to the nozzle row arrangement direction A and lands on the grid point 501 because the charging voltage is large. The droplet ejected at the timing T5 lands on the grid point 502. Since the droplets discharged at the timing T6 have opposite charge charges, they fly in the opposite direction to 501 and 502 and land on the grid point 503. The droplet discharged at the timing T7 has a larger absolute value of the charge amount than that at T6, and therefore, it is 5 on the grid point.
Landing on 04. In this way, the droplet can be landed on the grid point.

However, there may be a case where the droplet does not land on a desired grid point due to a displacement of the mounting position of the head module. This case can be solved by performing the deflection electric field shift described with reference to FIG. 2 and the timing shift of the charging voltage signal and the ink droplet ejection signal.
FIG. 5 shows a charge deflection signal and an ink ejection signal for explaining the charge voltage shift and the timing shift. FIG. 6 shows a schematic diagram of the result of the adjustment. For the sake of explanation, the coordinates are set on the recording paper in the X and Y directions shown in FIG. X is parallel to the paper movement direction, and Y is perpendicular to the paper movement direction.

When the nozzle position is at 104-1 shown in FIG. 6, the nozzle discharge timings T4, T5, T6, T7.
The landing positions of the droplets discharged and deflected by
2, 503, 504. Therefore, the landing positions 501 ′, 502 ′, 503 ′, and 504 ′ on the target grid point are displaced by dX in the X direction and dY in the Y direction.

The relationship between dX and dY between the landing position adjustment amount dD in the direction perpendicular to the A direction due to the deflection electric field shift and the landing position adjustment amount dF in the B direction due to the nozzle ejection timing shift is determined by using the head module mounting angle θ. , DY =
dDsin θ and dY = dD cos θ + dF. Therefore, the deflection electric field shift dEcshift shown in FIG. 5 has a value such that the resulting dDsinθ becomes dY.

Further, the nozzle discharge timing shift dTs
shift is d from the time when the recording paper is conveyed at this time.
The value is reduced by the amount corresponding to Dcos θ. As a result, the droplet landing positions 501, 502, 50 deviated from the grid points.
3, 504 on the corresponding grid points 501 ′,
The landing position can be corrected to 502 ', 503', 504 '.

A method for detecting and correcting the landing position displacement amount will be described below. FIG. 7 is a simplified diagram of a head module and a simplified diagram of a landing position deviation detection test pattern created by each head module. In the example of the drawing, a plurality of line segments that do not overlap each other are recorded by using the entire nozzle unit in the direction perpendicular to and parallel to the recording paper moving direction B. By recording a test pattern using more nozzles of the head module in this way, it is possible to absorb variations in nozzle characteristics. Also, when landing a plurality of droplets at the same point on a recording paper or at a determined relative position, such as in color recording, it is possible to perform not the local alignment but the entire alignment. It is possible to obtain a good image with less noticeable color misregistration as compared with the case where a test pattern is created by using only the nozzles of a part.

To simplify the explanation, X,
The Y coordinate is used. N head modules 101-
A test print pattern is printed from each of 1, 101-2, ..., 101-N. The printing patterns are roughly classified, and the deflection width of the ink droplet, that is, the deflection width measurement pattern 520 for correcting the amplitude of the charging voltage, and the landing position shift of the ink droplet ejected from the head unit in the X direction are detected and corrected. X position detection pattern 5 composed of a plurality of line segments in the Y direction for
21, a Y position detection pattern 522 including a plurality of line segments in the X direction for detecting a landing position deviation in the Y direction.
The X position detection pattern 521 is a line segment horizontal to the Y-axis direction, and the deflection width measurement pattern 520 and the Y position detection pattern 52 are
2 is an X-axis and a horizontal line segment. This is for simplifying the description, and each pattern may have a constant angle with respect to the coordinate system. In this example, the deflection width measurement pattern 520 and the Y position detection pattern 5 are
22 is a different pattern, the deflection width measurement pattern 52
The Y position detection pattern 523 can also be used with 1.

Although it has been described above that each pattern may have a constant angle with respect to the coordinate system, crosstalk occurs in a head module having a plurality of nozzles, and ink droplet landing occurs. Affect position. FIG. 13 shows an example of changes in the flight speed of ink droplets due to crosstalk. FIG. 13 shows a measurement of the ink droplet flight speed of the observation nozzle when the number of nozzles driven simultaneously with the observation nozzle is gradually increased from the vicinity of the observation nozzle. The closer the observation nozzles are to each other, and the larger the number of nozzles driven simultaneously, the greater the influence of crosstalk.

In the printed image, it is the fine lines recorded in the direction perpendicular to the recording paper movement direction that are greatly affected by the ink droplet landing displacement due to crosstalk. This is because the landing position shift due to the change in the speed of the ink droplet is large,
This is because the ink droplets landing in the vicinity are small and the deception due to bleeding or the like is not effective.

Due to this crosstalk, it is necessary to place restrictions on the X position detection pattern 521 of the landing position shift amount detection patterns. This will be described with reference to FIG. In order to simplify the description, deflected dots are not shown here. When the pattern is provided in the same direction as the A direction in the figure, all nozzles in the module eject at the same time, so the influence of crosstalk is the greatest, and therefore the vicinity of the angle θ must be avoided. Regarding the width of the pattern, since the error is smaller when θ is closer to 90 degrees in detecting the positional deviation amount in the Y direction on the condition that the adjacent nozzles are not ejected, in the case of the figure, it is the interval between the adjacent nozzles in the Y direction. 4 dots or less.

FIG. 8 shows a flow chart in the case of performing the ink drop landing position correction using the test pattern of FIG. First, in step 601, the test pattern is printed. Then, in step 602, the optical sensor 10
The test pattern is read by 5 and stored in a memory or the like as digital image data. For example, a CCD array can be used as the optical sensor. High-resolution image data can be acquired over a wide range by combining a CCD array in which the sensor spacing is accurately created, a lens, and illumination.

In step 603, virtual space coordinates are created on the stored image data. Virtual space coordinates are
Although any shape may be used as long as it is convenient for processing the image data, in this embodiment, an XY orthogonal coordinate system similar to that of the print sample is used. Thereafter, the steps of landing position detection and correction are entered.

Steps 604 to 608 are steps for detecting the deflection amplitude width of the ejected droplet. In step 604, the edge of the line segment of the test pattern 520 is detected. In step 605, an approximate straight line is calculated based on the detected edge of the line segment. An edge detection method, and
The method of calculating the approximate straight line is shown in FIG. For digital data captured by an optical sensor into a memory, for example, 2
When the masking of × 2 is performed and two or three pieces of data in the mask overlap the boundary portion of the captured digital data, it is regarded as an edge of a line segment. In this way, the edges of the line segment are detected at regular intervals at 705 in the figure. Then, the coordinates are stored. An approximate straight line 706 is calculated from the XY data of the stored coordinates. The approximate straight line can be obtained by using, for example, the least square method.

The left side of FIG. 9 is an example in which the edges on both sides of the line segment are detected and the center approximate straight line is obtained. It is also possible to use the edge on one side as shown in the right figure as a method for saving the amount of data processing and performing high-speed processing due to the detection time, data memory constraints, and the like. In step 606 in FIG. 8, the deflection amplitude is detected and the amplitude of the charging voltage is adjusted. FIG. 10 is an enlarged view of a part of the deflection width measurement pattern 520 of FIG. 7. FIG. 10 shows the case where the light is deflected in four stages.
The detection method will be described using this. First, a description will be given with reference to the diagram on the left of FIG. Approximate straight lines 706-1, 706-2, 70 of line segments recorded at each deflection stage by the method described with reference to FIG.
6-3 and 706-4 are obtained. With respect to the obtained straight line, intersections with the virtual reference line 705 in the Y-axis direction are obtained in virtual space coordinates, and the Y-direction distances dW1, dW2, dW3 between the intersections.
Is the deflection width of each deflection stage. Since 706-1 to 706-4 are not necessarily parallel, it is necessary to find the intersection with the reference line. In order to reduce the detection error, the virtual reference line 70
5 is preferably provided near each line segment. In this example, the reference line 705 is set approximately at the center of the total length of the line segments in the X direction. There is also a method in which 705-1, 705, 705-2, etc. are separately provided and dW1, dW2, and dW3 are obtained, respectively. If the method of measuring the widths of the four deflection stages without measuring the widths of the case deflection stages as shown in the right of FIG. 10, the measurement becomes simple.

In step 608, it is determined whether the deflection width thus obtained is within the design allowable range. If the deflection width is outside the design allowable value, an adjustment amount is calculated from the relationship between the deflection width and the charging voltage amount prepared in step 609, the print parameter is changed in step 618, and the test pattern is printed again in step 601. This is because the Y-direction position is affected if the deflection width is not adjusted. Step 6
When the deflection width is judged to be within the design allowable value in 07, X ・ Y
Detects and adjusts direction misalignment.

Steps 610 to 612 are for the Y direction, and steps 613 to 615 are steps for edge detection, approximate straight line calculation, and approximate straight line interval calculation in the X direction. By the same method as in the case of the deflection width, edge detection is performed for each line segment in the Y position detection pattern 522 (step 610) and an approximate straight line is obtained (step 61).
1). An example is shown in FIG. 707-1 to 707- in the figure
4 and 708-1 to 708-4 ... Approximate straight lines obtained for line segments created from one head module. Further, a plurality of virtual reference lines 705-1, 705-2, 705-3 ... Which are parallel to the Y axis in the virtual inter-coordinates are provided.

Next, a plurality of intersections between the virtual reference line and the approximate straight line are obtained, and an average line segment interval is obtained from the obtained intersections (step 612). A detailed description will be given by taking dY11 as an example. In the figure, the Y direction interval dY11 will be described as an example. Approximate straight lines 707-1 and 708-1 obtained from the line segment and the virtual reference line 7
The intersection point with 05-1 is obtained, and the distance dY111 in the Y direction is calculated. Similarly, distances are calculated for 705-2, 705-3, ... And the average thereof is set to dY11. Similarly,
The calculation is also performed for each approximate straight line, and each interval dY12, d
Ask for Y13. It is dY11 to dY24 in the figure that the Y component between the above-mentioned intersection points obtained with respect to the line segment formed from the nozzles at the same position in each head module is obtained.
The distance dY obtained as described above is 4
Since it is data, the average value dY1 is obtained as follows. dY1 = (dY11 + dY12 + dY13 + dY14)
/ 4 This dY1 is compared with the head module interval design value. Similarly, for dY2, dY2 = (dY21 + dY22 + dY23 + dY24)
/ 4 and compare with the designed head module interval. It is necessary to adjust in the Y direction by the error of the compared module intervals.

In this example, first, the approximate linear intervals were found for each reference line, and the head module interval was found from the average value. However, the head module interval was found from the approximate linear intervals for each reference line, and the average value was found. I don't care. The position error for each head module is obtained by the same procedure for the X direction. (Steps 613 to 615) The procedure in the X direction differs from the Y direction in that the angle on the coordinate is rotated by 90 degrees.

When obtaining the position error in this way, it is necessary to pay attention to the integration of the adjustment amount. If only the error between adjacent head modules is constantly measured, in the case of a line type printer having a large number of head modules, the position adjustment amount may be integrated and exceed the adjustment range in some cases. This should be avoided as the adjustment range becomes large and the device becomes complicated. Therefore, it is necessary to devise so that an integration error does not occur. For example, there is a method of calculating the positional deviation amount with respect to the reference head module as calculated above. In this way, the adjustment amount is not integrated. As a similar method, dYave = (dY1 + dY2 + dY3 + ... + dYN)
There is also a method of obtaining / N and setting the adjustment amount to dYave-dY1 dYave-dY2 dYave-dY3 ... dYave-dYN as follows.

Whether the position of each head module obtained as described above is within the X / Y position error allowable range is determined in step 616.
To judge. If all the values are within the range, the adjustment process ends. If the value is out of the range, the method described with reference to FIGS. 5 and 6 is clogged, a value for correction is obtained using the deflection voltage shift and the ink ejection timing shift in step 617, and the print parameters are corrected in step 618. , Print the test pattern again, and make it converge within the design allowable range.

FIG. 12 further shows an example of a method of removing an abnormal point and obtaining an approximate straight line in order to align the high-precision head module. As shown in the figure, when ink is scattered and so-called satellites or the like are generated to deteriorate the image, an error may occur in edge detection, and the approximate straight line may not be accurately calculated. To avoid this, first attach the approximate straight line 7 to the line segment edge obtained from the image data.
21 is requested. Interval estimation is performed on the obtained approximate straight line with a certain confidence interval, edge data having a large difference from the approximate straight line is regarded as an abnormal point, and excluded from the edge data for obtaining the approximate straight line. The approximate straight line 722 is obtained again from the new edge data excluding the abnormal point data. In this way, the influence of image deterioration factors such as satellites can be reduced, and more accurate position correction can be performed.

[0042]

According to the present invention, the positional relationship of the recording dot groups by the plurality of recording head modules is accurately grasped and the positional relationship is electrically adjusted, facilitating the automation of the adjustment and achieving high quality. It is possible to provide an inkjet recording device capable of recording an image at high speed.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a line scanning inkjet recording apparatus of the present invention.

FIG. 2 is a sectional view taken along the line CC ′ of FIG.

FIG. 3 is an explanatory diagram showing a relationship between a charge deflection voltage signal and a nozzle drive signal.

FIG. 4 is a schematic diagram of a result of recording by applying each signal.

FIG. 5 is an explanatory diagram showing a relationship between a charge deflection signal and an ink ejection signal.

FIG. 6 is a schematic diagram of a result of recording by applying each signal after adjustment.

FIG. 7 is an explanatory diagram of an example of a test pattern.

FIG. 8 is a flowchart of a landing position correction step.

FIG. 9 is a schematic diagram of a method for obtaining an approximate straight line segment.

FIG. 10 is a schematic diagram of a method for obtaining a deflection width.

FIG. 11 is a schematic diagram of a method of obtaining a head module interval.

FIG. 12 is a schematic diagram showing another method of obtaining an approximate straight line.

FIG. 13 is an observation example illustrating crosstalk.

FIG. 14 is a schematic view showing a pattern selection method.

[Explanation of symbols]

100 ... Recording paper, 101 ... Head module, 10
4 ... Nozzle array, 105 ... Optical sensor, 201 ... Signal processing unit, 202, 203 ... Charge deflection electrode driver, 204 ...
Nozzle drive driver, 301 ... Print data signal, 30
2, 303 ... Charge deflection data signal, 304 ... Ejection data signal, 305 ... Optical sensor control signal, 308 ... Nozzle drive signal, 309, 310 ... Charge deflection voltage, 306 ... Image reading data signal, 401 ... Piezoelectric element, 402 ... Vibrating plate, 403 ... Restrictor plate, 404 ... Chamber plate, 405 ... Orifice plate, 406 ... Orifice, 407 ... Ink drop, 705 ... Approximate straight line.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kunio Sato             Hitachiko, 1060 Takeda, Hitachinaka City, Ibaraki Prefecture             Machine Co., Ltd. (72) Inventor Hitoshi Kida             Hitachiko, 1060 Takeda, Hitachinaka City, Ibaraki Prefecture             Machine Co., Ltd. F-term (reference) 2C057 AF30 AG12 AL36 AN05 BA04                       BA14 DA09 DB04 DC02 DC10                       DC15 DD10 EA01

Claims (4)

[Claims] 1. A positional relationship between a plurality of recording head modules in which a plurality of nozzle holes for ejecting ink particles for forming an image on a recording medium are arranged substantially linearly, In an ink jet recording apparatus having means for detecting and adjusting based on recording dots formed by ink particles, the recording dots formed for detecting the positional relationship of the head module in the moving direction of the recording medium are the heads. An inkjet recording apparatus using the recording dots that are not ejected simultaneously from adjacent nozzles in a module. 2. The ink jet recording apparatus according to claim 1, further comprising first recording dot position adjusting means for moving the ink particles flying toward the recording medium in a direction substantially perpendicular to the nozzle array direction. An ink jet characterized by comprising: second recording dot position adjusting means for moving the ink particles in a relative movement direction of the recording medium, wherein the nozzle array direction is inclined with respect to the movement direction. Recording device. 3. The ink jet recording apparatus according to claim 1 or 2, wherein an approximate straight line is obtained for recording dots formed by the head module, and based on the approximate straight line, a relative movement direction of the recording medium in each head module is determined. An ink jet recording apparatus, wherein the means for obtaining the distance and the distance in the direction substantially perpendicular to the nozzle arrangement direction are obtained from a plurality of intersections of the approximate straight line and the reference line. 4. The ink jet recording apparatus according to claim 1, claim 2 or claim 3, wherein the first recording dot position adjusting means is an ink particle charging means for giving an electric charge to the ink particles, and is charged by the charging means. And a deflection electrostatic field forming means provided in the flight path of the ink particles so as to deflect the charged charged ink particles, and an ink particle deflection action adjusting means for adjusting the ink particle deflection action by these means. Inkjet recording device.