JP2009061755A - Inkjet recording apparatus and its control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording apparatus and a method for controlling therefor which can suppress the time taken for printing adjusting patterns and the consumption of a recording medium as well. <P>SOLUTION: The inkjet recording apparatus is provided with a printing head height changing means for changing the height of the printing head which ejects ink, an adjusting value detecting means which detects an adjusting value of a deviation amount between the ink ejecting position at the time of a two-way printing and the ink landing position at a plurality of heights of the printing head and a distance calculating means for calculating the distance between a nozzle row and the recording medium from the adjusting value and the height of the printing head detected by the adjusting value detecting means. Furthermore, the recording apparatus is provided with an ink ejection timing controller for controlling the ink ejection timing from the distance of the nozzle row and the recording medium calculated by the distance calculating means. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to an ink jet recording apparatus capable of preventing displacement of ink landing points in an ink jet recording apparatus capable of changing a print head height.

  An ink jet recording apparatus ejects ink from a print head onto a recording medium to form an image. The print head is equipped with fine nozzles for ink ejection. Since there is a distance between the nozzle and the recording medium, there is a difference between the ink ejection timing from the nozzle and the ink landing timing on the recording medium.

  For this reason, when forming an image, it is necessary to determine the ink discharge timing in consideration of the above-described deviation. For example, when the ink landing position is made to coincide during forward printing and backward printing in bidirectional printing, it is necessary to eject ink at a position shifted before the ink landing position. Since there is an individual difference in the shift amount, an adjustment pattern in which the shift amount is gradually changed is printed, and the shift amount in which the landing positions coincide is stored as an ink ejection timing adjustment value. In general, the ink discharge timing is determined using the adjustment value during printing.

  An inkjet recording apparatus in which the above processing is mounted prints on a recording medium having various thicknesses, and there is a printer that can adjust the distance from the nozzle to the recording medium by moving the print head up and down. In this configuration, the distance from the nozzle to the recording medium changes according to the thickness of the recording medium during printing and the height of the print head. It is assumed that the adjustment pattern is printed and the adjustment value is set at a certain print head height. In this case, if the distance between the nozzle recording media changes due to the change in the thickness of the recording medium or the print head moving up and down, the ink landing positions will not match.

  To solve this problem, an invention for printing an adjustment pattern with respect to the distance between two head recording media and setting two adjustment values with respect to the distance between the two head recording media with respect to the deviation adjustment value during bidirectional printing. Is known (see, for example, Patent Document 1).

Based on the above values, a relational expression between the distance between the head recording media and the adjustment value is derived. By applying the distance between the head recording media at the time of printing to the above relational expression, an adjustment value at the time of printing is calculated and the ejection timing is corrected.
JP 2000-198189 A

  Patent Document 1 describes only the same nozzle with respect to ejection timing correction during bidirectional printing. A configuration having an adjustment value for matching the landing positions of ink ejected from different nozzle arrays is also common.

  With respect to these adjustment values, the adjustment values do not match if the distance between the head recording media changes. Therefore, with respect to these adjustment values, an adjustment pattern may be printed for the distance between the two heads and the recording medium, and the same correction method as in Patent Document 1 may be used. However, in this case, there is a problem that it takes time to print the adjustment pattern, and when the adjustment pattern is used, many recording media are consumed.

  The distance between nozzle recording media is the print head height minus the thickness of the recording medium. Since the recording head height is determined by the mechanical mechanism, an accurate value can be known to some extent, but the thickness of the recording medium varies depending on the environment such as humidity. For this reason, the method of determining the thickness depending on the type of recording medium or the like lacks the accuracy of the value. In addition, the method of placing a measurement pattern for measuring the thickness of a recording medium has a problem that extra time is required for placing the measurement pattern.

SUMMARY OF THE INVENTION An object of the present invention is to provide an ink jet recording apparatus and a method for controlling the ink jet recording apparatus that can suppress the time required for printing an adjustment pattern and consumption of a recording medium.

The present invention relates to a print head height changing unit that changes the height of a print head that discharges ink, an adjustment value of a deviation amount between an ink discharge position and an ink landing position in bidirectional printing, and a plurality of print heads. And an adjustment value detecting means for detecting the height. The present invention further includes distance calculation means for calculating the distance between the nozzle array and the recording medium based on the adjustment value detected by the adjustment value detection means and the print head height. Furthermore, the present invention is an example of an ink jet recording apparatus having ink discharge timing control means for controlling ink discharge timing according to the distance between the nozzle row calculated by the distance calculation means and the recording medium.

According to the present invention, in the ink jet recording apparatus in which the distance between the nozzle array and the recording medium changes, the ejection timing adjustment pattern that needs to be printed with respect to a plurality of head heights determines the misalignment adjustment value for bidirectional printing. It's just a pattern. For this reason, there is no need to print the other ejection timing adjustment patterns by changing the height of the head, so that it is possible to reduce the time required for printing the adjustment pattern and the consumption of the recording medium.

  The best mode for carrying out the invention is the following embodiment.

  FIG. 1 is a schematic view of an inkjet recording apparatus PR1 that is Embodiment 1 of the present invention seen through from above.

  The ink jet recording apparatus PR1 includes a print head 1, a carriage 2, a guide shaft 3, an encoder film 4, a paper feed tray 6, a platen 7, and a paper discharge tray 8.

  The print head 1 is mounted on the carriage 2, and the carriage 2 moves along the guide shaft 3. The direction in which the carriage 2 moves is called the main scanning direction. In FIG. 1, the direction moving from right to left is called the forward direction, and the direction moving from left to right is called the backward direction. The encoder film 4 detects the current position of the print head 1.

  During printing, the recording medium 5 is fed from the paper feed tray 6, and under the print head 1, the recording medium 5 is supported by the platen 7 and intermittently conveyed to the paper discharge tray 8. This transport direction is referred to as the sub-scanning direction. The ink jet recording apparatus PR1 repeats the operation of ejecting ink from the print head 1 while conveying the recording medium 5 in the sub-scanning direction and moving the carriage 2 in the main scanning direction (this operation is called scanning). An image is formed on 5. A mechanism for moving the print head 1 up and down relative to the carriage 2 is provided in the carriage 2. With this mechanical function, the distance from the print head 1 to the recording medium 5 is changed.

  FIG. 2 is a block diagram illustrating a schematic configuration of the ink jet recording apparatus PR1.

  The ink jet recording apparatus PR1 includes an I / F 12, a print data conversion unit 13, a printer storage device 14, a printer control unit 15, a print control unit 16, a conveyance control unit 17, a carriage control unit 18, an ink ejection And a timing control unit 19.

  The I / F 12 receives image data from the host 10. The print data conversion unit 13 converts the image data transmitted from the host 10 into a data format ejected from the print head 1. The printer storage device 14 stores image data. The printer control unit 15 controls the entire printer.

  The print controller 16 determines a printing method based on the information converted by the print data converter 13 and controls the movement of the recording medium 5 in the sub-scanning direction and the movement of the carriage 2 in the main scanning direction. The conveyance control unit 17 moves the recording medium 5 in the sub scanning direction. The carriage control unit 18 controls the movement of the carriage 2.

  The ink discharge timing control unit 19 controls the ink discharge timing. That is, since the position of the carriage 2 where ink is desired to be ejected from each nozzle row can be designated by the ink ejection timing control unit 19, the ink ejection timing can be adjusted.

  That is, the carriage control unit 18 is an example of a print head height changing unit that changes the height of the print head that ejects ink. The print control unit 16 is an example of an adjustment value detection unit that detects an adjustment value of a deviation amount between the ink ejection position and the ink landing position during bidirectional printing with a plurality of print head heights. The print control unit 16 is an example of a distance calculation unit that calculates the distance between the nozzle array and the recording medium based on the adjustment value detected by the adjustment value detection unit and the print head height. Further, the ink discharge timing control unit 19 is an example of an ink discharge timing control unit that controls the ink discharge timing in accordance with the distance between the nozzle array and the recording medium calculated by the distance calculation unit.

  FIG. 3 is a view of the print head 1 as viewed from the recording medium 5 side.

  The print head 1 includes nozzle rows C-even, C-odd, M-even, M-odd, Y-even, Y-odd, K-even, and K-odd that eject ink.

  Cyan ink is ejected from the nozzle arrays C-even and C-odd, and magenta ink is ejected from the nozzle arrays M-even and M-odd. Yellow ink is ejected from the nozzle arrays Y-even and Y-odd, and black ink is ejected from the nozzle arrays K-even and K-odd.

  The even and odd nozzle rows of each color are close to each other, and the nozzles are alternately arranged in the vertical direction. The position of the carriage 2 is managed based on the nozzle row C-even. The ink ejection timing control unit 19 designates the ejection timing by position for each nozzle row, and this position is designated by the position of the carriage 2 (position of nozzle row C-even) for all nozzle rows. . Therefore, in order to match the discharge positions of different nozzle rows, it is necessary to set the discharge timing in consideration of the distance between the nozzle rows.

  The distances from the position of the nozzle row C-even to the nozzle rows M-even, Y-even, and K-even are Xcm, Xcy, and Xck, respectively. Further, the even nozzle row and the odd nozzle row are separated by Xoe. The nozzle array configuration of the print head 1 shown in FIG. 3 is an example, and the first embodiment can be applied to any print head having a plurality of nozzle arrays.

  FIG. 4 is a diagram illustrating the trajectory of ink ejection during bidirectional printing.

  FIG. 4A is a diagram illustrating a trajectory in which ink is ejected when the head height (the height of the print head 1) is h1. FIG. 4B is a diagram illustrating a trajectory in which ink is ejected when the head height is h2.

  There is a distance between the recording medium 5 and the print head 1 and the ink is ejected while the print head 1 is moving. Therefore, the ink follows an oblique trajectory according to the law of inertia. For this reason, even when the nozzles are at the same position, the ink landing position differs between forward printing and backward printing. Therefore, in order to match the ink landing positions, it is necessary to shift the ink discharge timing. Since there is an individual difference in the shift amount, a bidirectional adjustment pattern is printed, and an adjustment value for the shift amount is detected / set.

The adjustment value Rbi1 is an adjustment value of the deviation amount set when the height of the print head 1 is h1, and the adjustment value Rbi2 is the deviation amount of the deviation amount set when the height of the print head 1 is h2. It is an adjustment value. Here, if it is considered that ink ejection can be approximated to constant velocity motion, the bidirectional ejection timing adjustment value should be proportional to the distance between the nozzle array and the recording medium 5. That means
Bidirectional ejection timing adjustment value = 2 × print head speed × distance between nozzle array and recording medium / ink speed holds.

  In order to obtain the distance between the nozzle array and the recording medium 5, it is necessary to consider the thickness of the recording medium 5, and the following relational expression is approximately established.

Distance between nozzle array and recording medium 5 = head height−thickness of recording medium 5 Note that the above-mentioned “head height” is the distance between the platen 7 and the print head 1.

  However, the above relational expression may not be correctly established due to an error when the print head 1 is attached to the carriage 2.

  FIG. 5 is a graph plotting the relationship between the head height and the bidirectional ejection timing adjustment value using the bidirectional ejection timing adjustment values for the two head heights shown in FIG.

  In FIG. 5, the distance correction value ADJ between the nozzle array and the recording medium 5 is an intersection of a straight line extending from the point (h1, Rbi1) and the point (h2, Rbi2) and the head height axis. Is the distance from the origin. The distance correction value ADJ between the nozzle array and the recording medium 5 is a value that takes into account the thickness of the recording medium 5 and an error when the print head 1 is attached, and the following equation is established.

Distance between nozzle array and recording medium 5 = head height-ADJ
The distance correction value ADJ between the nozzle row and the recording medium 5 can be obtained for all nozzle rows by obtaining the bidirectional ejection timing adjustment value for all nozzle rows at two head heights. it can. The calculation formula is shown below: ADJ = h1-Rbi1 × (h2-h1) / (Rbi2-Rbi1) (1)
Further, the bidirectional ejection timing adjustment value Rbi when the head height is h can be calculated by the following equation (2).

Rbi = (Rbi2−Rbi1) / (h2−h1) × (h−h1) + Rbi1 (2)
In this example, linear interpolation is performed using two adjustment values for two head heights, but the relationship between the head height and the bi-directional ejection timing adjustment value using adjustment values for three or more head heights. The curve may be approximated using the least square method or the like.

  Even when the curve is approximated, the distance correction value ADJ between the nozzle array and the recording medium 5 can be obtained based on the intersection of the curve and the head height axis. In this example, the head height is the distance between the print head 1 and the platen 7, but if the thickness of the recording medium 5 is known by some method, the head height is determined by the print head 1 and the recording medium 5. It may be a distance. In this case, the distance correction value between the nozzle array and the recording medium 5 is a value for correcting the head mounting error, and even if the thickness of the recording medium 5 changes, there is no need to recalculate.

  Next, the discharge timing adjustment between the nozzle rows will be described.

In the nozzle row configuration shown in FIG. 3, adjustment of the even row and odd row of each color and adjustment of ejection timing between the even rows of different colors are performed. That is, the following nozzle rows are adjusted.
・ C-even C-odd (C-even standard)
・ Between M-even and M-odd (M-even standard)
・ Y-even Y-odd (Y-even standard)
・ Between K-even and K-odd (K-even standard)
・ C-even M-even (C-even standard)
・ C-even Y-even (C-even standard)
・ C-even K-even (C-even standard)
In this case, if the ink ejection direction is the same, the ejection timing may be shifted by the distance between the nozzle rows. However, since there are ink differences and individual differences in the ink ejection direction, an ejection timing adjustment value between nozzle rows is necessary.

  Since the basic concept is the same for any adjustment between nozzle rows, adjustment between C-even Y-even will be described below.

  FIG. 6 is a diagram illustrating the trajectory of ink ejection from the nozzle row C-even and the nozzle row Y-even.

  Consider that ink ejected from each nozzle row is landed on the same position of the recording medium 5. If the gradients of the ink ejection vectors match, the ejection timing of the nozzle array Y-even relative to the ejection timing of the nozzle array C-even by the distance Xcy between the nozzle array C-even and the nozzle array Y-even. Can be delayed.

  However, in actuality, since the gradients of the ink ejection vectors do not exactly match, if the adjustment value is introduced and the ejection timing is shifted by the “Xcy-C-even Y-even adjustment value”, the landing positions match. I think so. This adjustment value can be detected / set by printing an adjustment pattern or the like.

  FIG. 6A is a diagram illustrating a case where the adjustment value between the nozzle row C-even and the nozzle row Y-even is Rcy1 when the head height is h1.

  FIG. 6B is a diagram illustrating a case where the adjustment value between the nozzle row C-even and the nozzle row Y-even is Rcy2 when the head height is h2.

  Even when the head height is h2, the adjustment pattern can be printed and the adjustment value Rcy2 can be detected / set, but in this case, the time for printing the adjustment pattern and the consumption of the recording medium 5 increase. Therefore, a distance correction value between the nozzle array and the recording medium 5 is obtained from the head height and the bidirectional ejection timing adjustment value, and the distance correction value between the nozzle array and the recording medium 5 is used to determine the head height h1. Based on the inter-nozzle row adjustment value, the inter-nozzle row adjustment value at another head height is obtained. This method is described below.

  Assume that the distance correction value between the nozzle array C-even and the recording medium 5 is ADJ_ce, and the distance correction value between the nozzle array Y-even and the recording medium 5 is ADJ_ye. Let d be the difference between the ejection position and the landing position of the nozzle row C-even at the head height h1.

  Hereinafter, the adjustment value Rcy2 at the head height h2 is obtained.

Since the slopes of the ink ejection vectors from the same nozzle row match,
(D + Rcy1) × (h2−ADJ_ye) / (h1−ADJ_ye) = d × (h2−ADJ_ce) / (h1−ADJ_ce) + Rcy2
When the above equation is transformed,
Rcy2 = Rcy1 * (h2-ADJ_ye) / (h1-ADJ_ye)
+ (ADJ_ce−ADJ_ye) × d (h1−h2) / (h1−ADJ_ye) (h1−ADJ_ce)
It becomes. Here, since the term ADJ_ce-ADJ_ye is a minute value, if it is ignored, the following can be derived.

Rcy2 = Rcy1 × (h2−ADJ_ye) / (h1−ADJ_ye) (3)
Therefore, if the adjustment value Rcy1 between the nozzle rows at the head height h1 and the distance correction value ADJ_ye between the nozzle row and the recording medium 5 are known, the adjustment value Rcy2 between the nozzle rows at the head height h2 can be calculated. it can.

  This example is an example relating to the adjustment values of the nozzle row C-even and the nozzle row Y-even, but the adjustment values between the other nozzle rows are the same as the above-described concept.

  FIG. 7 is a diagram illustrating an example of a conventional adjustment pattern.

  A bidirectional adjustment pattern is printed with head heights 1 and 2 for all nozzle rows. The upper part of the pattern is printed in the forward direction, and the lower part of the pattern is printed in the backward direction. Patterns 1 to 7 with the bidirectional print ejection timing adjustment value gradually shifted are printed, and the ejection timing for the pattern without deviation is stored as the adjustment value.

  The odd-even adjustment pattern prints the odd-even adjustment pattern at head heights 1 and 2 for C, M, Y, and K. The black portion of the pattern is printed in the even row, and the gray portion is printed in the odd row. The patterns 1 to 7 with the ejection timing gradually shifted are printed, and the ejection timing corresponding to a pattern with no gap in the odd-even pattern is stored as an adjustment value.

  Further, the inter-color adjustment pattern includes the nozzle row C-even and the nozzle row M-even, the nozzle row C-even and the nozzle row Y-even, the nozzle row C-even and the nozzle row Y-even. In between, the adjustment pattern is printed at the head heights 1 and 2. The black portion of the pattern is printed with the nozzle row C-even, and the gray portion is printed with the nozzle row even of other colors. The patterns 1 to 7 with the ejection timing gradually shifted are printed, and the ejection timing corresponding to the pattern having no gap in the pattern is stored as the adjustment value.

  FIG. 8 is a diagram illustrating an example of an adjustment pattern in the first embodiment.

  In this case, the bidirectional adjustment pattern is printed at the head heights 1 and 2, but the odd-even adjustment pattern and the inter-color adjustment pattern are printed only at the head height 1. Using the bidirectional adjustment pattern, based on the bidirectional ejection timing adjustment values set at the two head heights, the distance correction value between the nozzle array and the recording medium 5 is obtained using Equation (1) and stored. .

  If the distance correction value between the nozzle array and the recording medium 5 can be calculated, the ejection for other head heights can be performed based on the odd-even ejection timing adjustment value and intercolor ejection timing adjustment value for a certain head height. Timing adjustment values can be calculated.

  Therefore, it is not necessary to print the odd-even adjustment pattern and the inter-color adjustment pattern at the head height 2.

  According to the first embodiment, the consumption of the recording medium 5 can be suppressed as compared with the conventional example, and the time required for the adjustment pattern printing can be suppressed as compared with the conventional example.

  FIG. 9 is a diagram illustrating adjustment values to be stored and values related thereto in the first embodiment.

  Bidirectional adjustment values need to store adjustment values for two head heights, but odd-even adjustment values and inter-color adjustment values need only store adjustment values for a certain head height. In addition, the nozzle row storage medium distance correction value is obtained and stored in accordance with the bidirectional adjustment value for the two head heights.

  FIG. 10 is a flowchart illustrating an operation of calculating the ejection timing at the time of scan printing in the first embodiment.

  In S1, the printing range on the recording medium 5 is converted into an encoder coordinate system (ejection position) based on the nozzle array C-even. The discharge position is, for example, a discharge start position and a discharge end position. The ejection position is calculated for each nozzle row.

  Since the ejection position is based on the nozzle row C-even, the distance between the nozzle rows from the nozzle row C-even is added except for the nozzle row C-even. For example, consider a case where the print range on the recording medium 5 of the nozzle array C-even and the nozzle array M-even is the same. In this case, the ejection position of the nozzle row M-even is a position obtained by adding the inter-nozzle row distance Xcm to the ejection position of the nozzle row C-even.

  In S2, the current head height is acquired. In S3, a value calculated based on the head height acquired in S2, the inter-color adjustment value obtained by the adjustment pattern shown in FIG. 8, and the distance correction value between the nozzle array and the recording medium 5 is calculated from the ejection position of the corresponding nozzle. Subtract. Here, the “corresponding nozzle” is a nozzle other than the reference nozzle for color adjustment. For example, in the inter-color adjustment between the nozzle row C-even and the nozzle row M-even, the nozzle row M-even.

  In addition, h2 in the above formula (3) is replaced with the current head height, h1 is replaced with the head height at the time of adjustment pattern printing, and other variables are replaced with the corresponding nozzle row values. To do.

  In S4, the head height acquired in S2, the odd-even adjustment value obtained by the adjustment pattern shown in FIG. 8, the value calculated based on the distance correction value between the nozzle array and the recording medium 5, and the ejection position of the corresponding nozzle. Subtract from

  The “corresponding nozzle” is a nozzle other than the reference nozzle for odd-even adjustment, and in this case, is an odd nozzle row. Further, an expression is used in which h2 in Expression (3) is replaced with the current head height, h1 is replaced with the head height at the time of printing the adjustment pattern, and other variables are replaced with the values of the corresponding nozzle rows. .

  Next, in S5, it is determined whether or not the printing direction is the forward direction. If the print is in the forward direction, in S6, the value calculated based on the head height and the bidirectional adjustment value is subtracted from the ejection position of the corresponding nozzle row. Here, the discharge position becomes larger toward the forward direction. The bidirectional discharge timing adjustment value is halved and assigned in the forward direction and the backward direction.

  That is, in the forward direction, 1/2 of Rbi calculated by the above equation (2) is subtracted. If it is not the forward direction in the condition determination S5, the value calculated based on the head height and the bidirectional adjustment value is added to the ejection position of the corresponding nozzle row in S7. The value to be added is 1/2 of Rbi calculated by Expression (2), as in the case of forward printing. Finally, in S8, the ejection position is set in the ink ejection timing control unit 19. The ink ejection timing control unit 19 ejects ink at an appropriate position based on the ejection position set for each nozzle row.

The above embodiment can be grasped as a method invention. That is, in the above-described embodiment, the print head height changing step for changing the height of the print head that discharges ink, and the adjustment value of the deviation amount between the ink discharge position and the ink landing position at the time of bidirectional printing, And an adjustment value detection step of detecting at the print head height. In the embodiment, the distance calculation step of calculating the distance between the nozzle array and the recording medium based on the adjustment value detected in the adjustment value detection step and the print head height and storing the distance in the storage device. Have. Further, the above embodiment has an ink ejection timing control step for controlling the ink ejection timing in accordance with the distance between the nozzle array and the recording medium calculated in the distance calculation step.

It is the schematic which saw through the inkjet recording device PR1 which is Example 1 of this invention from the upper surface. It is a block diagram showing schematic structure of inkjet recording device PR1. FIG. 3 is a diagram of the print head 1 as viewed from the recording medium 5 side. It is a figure which shows the locus | trajectory of the ink discharge at the time of bidirectional printing. FIG. 6 is a graph plotting the relationship between the head height and the bidirectional ejection timing adjustment value using the bidirectional ejection timing adjustment values for the two head heights shown in FIG. 4. It is a figure which shows the locus | trajectory of the ink discharge from nozzle row C-even and nozzle row Y-even. It is a figure which shows the example of the conventional adjustment pattern. 5 is a diagram illustrating an example of an adjustment pattern in Embodiment 1. FIG. In Example 1, it is a figure which shows the adjustment value memorize | stored and the value relevant to this adjustment value. 6 is a flowchart illustrating an operation of calculating ejection timing during scan printing in the first embodiment.

Explanation of symbols

1 ... print head,
2 ... carriage,
3 ... Guide shaft,
4 ... Encoder film,
5 ... Recording medium,
6 ... feed tray,
7 ... Platen,
8 ... Output tray,
10 ... Host,
12 ... I / F,
13: Print data conversion unit,
14 ... Printer storage device,
15 ... Printer control unit,
16: Print control unit,
17 ... conveyance control unit,
18 ... Carriage controller,
19: Ink ejection timing control unit.

Claims (2)

Print head height changing means for changing the height of the print head for ejecting ink;
Adjustment value detecting means for detecting an adjustment value of a deviation amount between the ink discharge position and the ink landing position at the time of bidirectional printing at a plurality of print head heights;
Distance calculating means for calculating the distance between the nozzle array and the recording medium based on the adjustment value detected by the adjustment value detecting means and the print head height;
Ink ejection timing control means for controlling the ink ejection timing in accordance with the distance between the nozzle array and the recording medium calculated by the distance calculation means;
An ink jet recording apparatus comprising: A print head height changing step for changing the height of the print head that ejects ink;
An adjustment value detecting step of detecting an adjustment value of a deviation amount between the ink discharge position and the ink landing position at the time of bidirectional printing at a plurality of print head heights;
A distance calculation step of calculating a distance between the nozzle array and the recording medium based on the adjustment value detected in the adjustment value detection step and the print head height and storing the distance in the storage device;
An ink ejection timing control step for controlling the ink ejection timing in accordance with the distance between the nozzle array and the recording medium calculated in the distance calculation step;
A method for controlling an ink jet recording apparatus, comprising:

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