JP2010023294A - Image recording device, control method for image recording device, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image recording device capable of performing high-definition image recording even if a conveying mechanism for conveying a recording medium causes variation in the conveying speed of the recording medium, and to provide a control method for the image recording device and its program. <P>SOLUTION: A storage part 3 stores correction parameters for correcting the timing to cause nozzle rows 7 (7-1 to 7-N) to eject ink. An input part 19 obtains the selection input of the correction parameters. Correcting parts 5 (5-1 to 5-M) correct the timing for each nozzle row 7 (7-1 to 7-N) based on detected information on a starting point of a conveyor belt 10 generated by a starting point detecting part 12, conveyance information on the recording medium generated by a conveyance information generating part 11, and the selected correction parameters. A recording timing control part 18 controls ejection of ink from the nozzle rows 7 (7-1 to 7-N) at the corrected timing. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image recording technique, and more particularly to a technique for recording an image at an appropriate position on a recording medium in an image recording apparatus that performs a recording process on the recording medium.

  2. Description of the Related Art As an image recording apparatus that records an image on a recording medium such as paper or film, an ink jet method that records an image by ejecting ink from a nozzle array is known. Such an ink jet method includes a full line type using a recording unit in which a plurality of short nozzle rows (recording heads) that are easy to manufacture and inexpensive are arranged so that a necessary image recording width can be recorded. In addition, the image recording apparatus includes such a recording unit for each color ink such as cyan, magenta, yellow, and black, respectively, and can record a color image. Some of them are

  As a recording medium conveyance mechanism in such an image recording apparatus, a system using an endless belt is known. In this system, for example, an endless belt is installed on rollers installed in parallel, and the endless belt is rotated by rotating the rollers. The recording medium is placed on the endless belt and conveyed. Hereinafter, this endless belt is referred to as a “conveyance belt”.

In order to perform high-quality image recording with an image recording apparatus that records color images, it is important to match the recording positions of the images with the inks of the respective colors.
In the above-described ink jet type image recording apparatus, the timing for ejecting ink (recording timing) is controlled to correct the image recording position of each color. As a timing signal representing the timing, for example, a method using a pulse signal generated by a rotary encoder attached to the shaft of a roller rotating a conveyor belt is known. However, in this method, if there is uneven thickness of the conveyor belt, uneven speed occurs in the conveyor belt, and the moving distance of the conveyor belt corresponding to one pulse of the timing signal changes. Then, since the distance between the recording dots constituting the image changes, there is a problem in that the recording position of the image of each color is shifted, and as a result, the image quality is deteriorated.

In order to solve such a problem, for example, a technique disclosed in Patent Document 1 has been proposed. In this technique, a conveyance start point is provided on the conveyance belt of the conveyance mechanism, and the image forming apparatus includes a conveyance start point detection unit that detects the position of the conveyance start point and a correction unit that corrects the recording timing. . Then, the recording timing obtained based on the detection of the conveyance start point is corrected according to the speed fluctuation of the conveyance belt measured in advance.
JP 2005-305919 A

However, the technique of Patent Document 1 requires a measuring instrument such as a laser Doppler meter or an ultrasonic Doppler meter for measuring the moving speed of the conveyor belt.
In the technique of Patent Document 1, it is difficult to measure the speed fluctuation of the conveyor belt when it is incorporated in the image recording apparatus, and it is necessary to measure the conveyor belt alone.

Further, in the technique of Patent Document 1, it is possible to correct the change in the speed of the transport belt in the initial state, but it is not possible to correct the speed change caused by the change with time of the transport belt or the like.
Accordingly, the present invention has been made in view of the above-described problems, and can perform high-quality image recording even when a conveyance mechanism that conveys a recording medium causes fluctuations in the conveyance speed of the recording medium. It is an object of the present invention to provide a recording apparatus, an image recording apparatus control method, and a program thereof.

  In order to achieve the above-described object, an image recording apparatus according to one aspect of the present invention generates a starting point detection information by detecting a starting point of a conveying belt that conveys a placed recording medium, and performs the recording. A conveyance mechanism that generates medium conveyance information; and a plurality of recording units that include a plurality of nozzle arrays including a plurality of nozzles in a direction orthogonal to the conveyance direction of the recording medium. In the image recording apparatus that performs the recording process on the recording medium by ejecting ink from the nozzle row of the recording unit in the process, correction parameters respectively associated with the nozzle rows of the plurality of recording units, A storage unit for storing the correction parameter for correcting the timing of ejecting ink to the nozzle row, an input unit for selecting and setting the correction parameter, and origin detection information And a plurality of correction units for correcting the timing of ejecting ink from the nozzle row for each nozzle row based on the conveyance information and the correction parameter selected by the selection input, and the timing corrected by the correction unit And at least a control unit that includes a recording timing control unit that performs control for ejecting ink from the nozzle array.

  According to another aspect of the present invention, there is provided a control method for an image recording apparatus that detects a starting point of a conveying belt that conveys a placed recording medium to generate starting point detection information, and A process of transporting a recording medium, comprising: a transport mechanism that generates transport information; and a plurality of recording units each having a plurality of nozzle rows each including a plurality of nozzles in a direction orthogonal to the transport direction of the recording medium. And a correction parameter associated with each of the nozzle rows of the plurality of recording units. The correction parameter for correcting the timing of ejecting ink to the nozzle row is stored in the storage unit provided in the image recording apparatus, and the correction parameter The input of selection is acquired by the input unit provided in the image recording apparatus, and the correction unit provided in the image recording apparatus selects the correction parameter selected by the input of starting point detection information and conveyance information and selection. Based on the above, the timing at which ink is ejected from the nozzle row is corrected for each nozzle row, and the recording timing control unit provided in the image recording apparatus performs the ink ejection from the nozzle row at the timing corrected by the correction unit. Performing discharge control.

  In addition, a program that is one of further another aspects of the present invention generates a starting point detection information by detecting a starting point of a conveying belt that conveys a placed recording medium, and also carries the conveying information of the recording medium. A recording unit in the process of transporting the recording medium, and a plurality of recording units each including a plurality of nozzle units each including a plurality of nozzle arrays in a direction orthogonal to the recording medium transport direction. Is a program for causing an arithmetic processing unit to control an image recording apparatus that performs recording processing on a recording medium by ejecting ink from the nozzle arrays, each corresponding to a nozzle array of a plurality of recording units The correction parameter to be added and used to correct the timing for ejecting ink to the nozzle row is stored in a storage unit provided in the image recording apparatus. Storage processing to be performed, input processing for input of correction parameter selection to be acquired by an input unit provided in the image recording apparatus, and origin correction information, conveyance information, and correction parameters selected by input of selection Causing the arithmetic processing unit to perform a correction process for correcting the timing of ejecting ink from the nozzle array for each nozzle array, and a control process for performing control of ejecting ink from the nozzle array at the corrected timing. It is characterized by.

  According to the present invention, an image recording apparatus capable of performing high-quality image recording even when the transport mechanism that transports the recording medium causes fluctuations in the transport speed of the recording medium, as described above, An image recording apparatus control method and program thereof can be provided.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the following description, the conveyance direction of the recording medium is defined as the y direction or the sub-scanning direction, and the direction orthogonal to the conveyance direction in the plane of the recording medium is defined as the x direction or the main scanning direction. The direction orthogonal to both the direction and the y direction is defined as the z direction.

1 and 2 will be described. FIG. 1 shows a configuration of an image recording apparatus according to the present embodiment. FIG. 2 shows an arrangement example of each component of the image recording apparatus according to the present embodiment.
The image recording apparatus 1 includes at least a control unit 2, a nozzle row driving unit 6, a nozzle row 7, a transport mechanism 8, and an input unit 19.

  The control unit 2 controls various operations of the image recording apparatus 1 such as control of the transport mechanism 8 and image data processing. The control unit 2 includes at least a processing circuit (not shown) including, for example, a micro processing unit (MPU) in an arithmetic processing device having a control function and an arithmetic function, a storage unit 3, and a recording timing control unit 18.

  The storage unit 3 includes a read only memory (ROM) that stores a control program, a random access memory (RAM) that serves as a work memory of the MPU, and a nonvolatile memory that stores designation information for recording processing including recording data. It is comprised.

  The recording timing control unit 18 includes at least a timing control program 4 and a correction unit 5. The recording timing control unit 18 operates according to the procedure recorded in the timing control program 4. The timing signal (conveyance information) input from the conveyance information generation unit 11 is corrected by the correction unit 5 and the nozzle row driving unit 6. Output to.

  The correction unit 5 (5-1 to 5-M) corrects and outputs the timing signal input from the conveyance information generation unit 11 according to a correction parameter described later. The correction parameter is stored in advance in the storage unit 3, for example, and is set in the correction unit 5 when the recording timing control unit 18 operates according to the timing control program 4. Although details will be described later, in the arrangement example of FIG. 2, M = 12.

  The control unit 2 controls each component of the image recording apparatus 1 when the MPU reads the control program from the storage unit 3 and executes it, and further provides a function as the recording timing control unit 18.

  The nozzle row driving unit 6 (6-1 to 6-N) is configured to perform nozzle row 7 (7) according to the timing signal output from the recording timing control unit 18 of the control unit 2 in accordance with the image data input from the control unit 2. -1 to 7-N) perform ink ejection to perform image recording on the recording medium. Although details will be described later, in the arrangement example of FIG. 2, N = 16.

The transport mechanism 8 includes at least a drive unit 9, a transport belt 10, a transport information generation unit 11, a start point mark 12, and a start point detection unit 13, and transports the recording medium 17.
The drive unit 9 rotates the drive roller 15 to rotate the transport belt 10.

The conveyor belt 10 is installed between the driving roller 15 and the driven roller 16 and carries the recording medium 17 thereon.
The conveyance information generation unit 11 is attached to the driving roller 15 and outputs a pulse signal to the control unit 2 every time the driving roller 15 rotates by a predetermined angle. The starting point mark 12 specifies the position of the conveyance belt 10. It is used for this purpose. The starting point mark 12 is a small plate that reflects light, for example, and is attached to one place on the conveyor belt 10, and the origin of the plate is determined by the difference in light reflectance between the plate and the conveyor belt 10. The detection unit 13 is configured to be able to detect.

  The starting point detection unit 13 is, for example, an optical sensor provided at a position facing the conveying belt 10 at one point on the line through which the starting point mark passes through the rotation of the conveying belt 10. The starting point detection unit 13 detects that the starting point mark 12 has reached a specific position by the rotation of the conveyor belt 10 and outputs a starting point detection signal (starting point detection information) to the control unit 2.

  The host device 14 is a personal computer, for example, and sends image data to the image recording apparatus 1 to instruct image recording. The image recording apparatus 1 performs image recording based on image data received from the host device 14 in accordance with an instruction from the host device 14.

The input unit 19 acquires correction parameter selection and setting input by a user or the like.
2 will be further described.
The image recording apparatus 1 according to the present embodiment records a color image using inks of four colors, cyan, black, magenta, and yellow. For each color, an image is divided into four recording rows and image recording is performed using four nozzle rows 7. Accordingly, 4 × 4 = 16 nozzle rows 7-1 to 7-16 are provided.

  The nozzle rows 7-1 to 7-4, 7-5 to 7-8, 7-9 to 7-12, and 7-13 to 7-16 are each composed of a plurality of nozzles, and are in the transport direction of the recording medium 17. Are arranged in the orthogonal direction. The nozzle rows 7-1 to 7-16 are provided to face the conveyance belt 10 so that ink droplets can adhere to the recording medium 17 conveyed by the conveyance belt 10. When ink droplets are ejected from the nozzle rows 7-1 to 7-16 during the conveyance of the recording medium 17, image recording is performed.

A more detailed arrangement of the nozzle rows 7-1 to 7-16 is shown in FIG.
As shown in FIG. 3, the nozzle rows 7-1 to 7-4 record cyan images, the nozzle rows 7-5 to 7-8 record black images, and the nozzle rows 7-9 to 7-7. −12 performs magenta image recording, and the nozzle arrays 7-13 to 7-16 perform yellow image recording. Here, the nozzle rows 7-1, 7-5, 7-9, and 7-13 perform image recording of the left end portion in the transport direction. This portion is the first recording row. In addition, the nozzle rows 7-2, 7-6, 7-10, and 7-14 perform image recording of the portion of the second recording row adjacent to the right side of the first recording row. Similarly, the nozzle rows 7-3, 7-7, 7-11, and 7-15 perform image recording of the portion of the third recording row adjacent to the right side of the second recording row. The nozzle rows 7-4, 7-8, 7-12, and 7-16 are images of the portion of the fourth recording row adjacent to the right side of the third recording row, that is, the rightmost portion in the transport direction. Make a record.

Returning to the description of FIG.
The nozzle arrays 7-1 to 7-16 are connected to the outputs of the nozzle array driving units 6-1 to 6-16, respectively. Inputs of the nozzle array driving units 6-1 to 6-16 are connected to the control unit 2.

  The control unit 2 includes a total of twelve correction units 5-1 to 5-12 in this embodiment. The reason for twelve is that the timing signals for the remaining three colors are based on the timing signals applied to one of the four-color nozzle rows 7-1 to 7-16. This is because the correction is performed. That is, 4 [number of nozzle rows / color] × 3 [color] = 12 [number of nozzle rows]. Here, if the number of colors of the nozzle row 7 is X and the number of nozzle rows per color for each color is Y, the number M of the correction units 5 is M = (X−1) × Y. .

  In the present embodiment, the timing signals corrected by the correcting units 5-1 to 5-12 are respectively input to the nozzle array driving units 6-5 to 6-16. The nozzle row driving units 6-1 to 6-4 are operated as reference nozzle row driving units by inputting the timing signals that are not corrected as they are.

Next, the operation at the time of image recording in the image recording apparatus 1 according to the present embodiment will be described.
When image data is input from the host device 14 to the image recording apparatus 1, the image data is held in an image memory (not shown) provided in the storage unit 3 of the control unit 2.

  The control unit 2 reads the image data held in the image memory and divides it according to the respective image recording ranges of the nozzle arrays 7-1 to 7-16. Then, the ink droplets are output to the corresponding nozzle row driving units 6-1 to 6-16 in synchronization with the ink droplet ejection operations from the nozzle rows 7-1 to 7-16.

Further, the control unit 2 controls the driving unit 9 of the conveyance mechanism 8 to rotate the driving roller 15 according to the instruction, thereby rotating the conveyance belt 10 and conveying the recording medium 17.
The conveyance information generation unit 11 generates a timing signal corresponding to the rotation of the driving roller 15 by the rotation of the conveyance belt 10 and sends the timing signal to the control unit 2.

The start point detection unit 13 sends a start point detection signal to the control unit 2 every time the start point mark 12 is detected by the rotation of the conveyor belt 10.
The control unit 2 inputs the timing signal sent from the conveyance information generation unit 11 and the start point detection signal sent from the start point detection unit 13 to the recording timing control unit 18.

The recording timing control unit 18 executes the timing control program 4. Then, the following processing is performed by the recording timing control unit 18.
First, the recording timing control unit 18 performs a process of calculating the belt position L from the timing signal and the starting point detection signal.

  The belt position L is, for example, a value from “0” to “255” by dividing the length of one round of the conveyor belt 10 into 256 by setting the position where the starting point detection unit 13 detects the starting point mark 12 to “0”. To express. The number of divisions can be determined as appropriate. Here, if the number of divisions is increased, timing correction according to the belt position L can be finely performed. If the number of divisions is reduced, coarse correction is performed, but the processing load on the recording timing control unit 18 is reduced.

  Next, the recording timing control unit 18 increases the belt position L by “1” according to the number of pulses of the timing signal. When the starting point detection signal is detected, the belt position L is reset to “0”. The number of pulses of the timing signal for increasing the belt position L by “1” is a number obtained by dividing the number of pulses of the timing signal generated by the conveyance information generation unit 11 while the conveyance belt 10 is rotated once by 256. .

  With these processes, the belt position L becomes “0” when the conveying belt 10 is located at a position where the starting point mark 12 faces the starting point detection unit 13, and the belt position L becomes “255” while the conveying belt 10 makes one round. Change to.

  In addition, the control unit 2 does not perform frequency correction on the timing signal sent from the conveyance information generation unit 11, and the nozzle row driving unit 6-corresponding to the first color nozzle rows 7-1 to 7-4. 1 to 6-4 are output as they are, and are also sent to the correction units 5-1 to 5-12. The nozzle row driving units 6-1 to 6-4 drive the nozzle rows 7-1 to 7-4 according to the timing signals, respectively, and eject ink droplets to record an image.

The storage unit 3 stores a correction table corresponding to each of the correction units 5 (5-1 to 5-12) in advance. An example of this correction table is shown in FIG.
The correction table illustrated in FIG. 4 associates the belt position L with the correction amount c of the timing signal. The correction amount c represents the rate at which the frequency of the timing signal (the reciprocal of the pulse period) increases in percent units. A series of correction amounts c in this table are referred to as “correction parameters”. In the following description, the change characteristic of the correction parameter value with respect to the belt position L is referred to as “correction characteristic”.

  The recording timing control unit 18 reads out correction parameters corresponding to each of the correction units 5 (5-1 to 5-12) from the storage unit 3 in accordance with the timing control program 4, and corrects the correction units 5 (5-1 to 5-5). 12) The processing set for each is performed.

  Next, the recording timing control unit 18 performs processing for inputting the belt position L to the correction unit 5 (5-1 to 5-12) according to the timing control program 4. This input process is performed every time the value of the belt position L changes, and the value is input to the correction unit 5 (5-1 to 5-12).

  The correction unit 5 (5-1 to 5-12) refers to the correction parameter and obtains the correction amount of the frequency of the timing signal corresponding to the belt position L acquired according to the timing control program 4. Then, the frequency of the input timing signal is changed according to the obtained correction amount. As a method of changing this frequency, for example, a method of controlling the oscillation frequency of the variable frequency oscillator (VCO) based on the frequency of the timing signal by phase lock loop control (PLL control) (see, for example, FIG. 6 of Patent Document 1). Such a well-known technique can be used.

  The control unit 2 receives the timing signals input from the conveyance information generation unit 11 and subjected to frequency correction by the correction units 5 (5-1 to 1-12), and the nozzle rows 7-5 to 7 for the second and subsequent colors. It is sent to the nozzle array driving units 6-5 to 6-16 corresponding to -16 respectively. The nozzle array driving units 6-5 to 6-16 drive the nozzle arrays 7-5 to 7-16 in accordance with the timing signals to discharge ink droplets and record an image. In this way, the timing at which ink is ejected from the nozzle rows 7-5 to 7-16 is corrected.

Next, the image recording position shift caused by the conveyance belt 10 and the correction of the shift will be described.
FIG. 5 shows that the nozzle row 7-1 for the first color and the nozzle row 7-5 for the second color that perform image recording of the first recording row eject ink droplets to form dots (dots) on the recording medium 17. ) Is schematically shown in the state of image recording.

In FIG. 5, the recording medium 17 is conveyed in the right direction (y-axis direction) in FIG.
FIG. 5A shows a state at the time when the nozzle row 7-1 ejects ink droplets of the first color and records the recording dots 20a on the recording medium 17. FIG.

  First, a case is assumed in which the thickness of the transport belt 10 is uniform and the amount of movement of the transport belt 10 per pulse of the timing signal output from the transport information generation unit 11 is constant. In this case, an ink droplet may be ejected from the nozzle row 7-5 when a predetermined number of timing signal pulses are counted from the state (a). That is, when ink droplets are ejected in this way, the recording dots 20a recorded by the nozzle row 7-1 and the recording dots 20b recorded by the nozzle row 7-5 overlap as shown in FIG. As a result of recording both without positional deviation, a recorded image with good image quality can be obtained.

  Next, it is assumed that the amount of movement of the conveyance belt 10 per pulse of the timing signal output from the conveyance information generation unit 11 varies due to a non-uniform thickness of the conveyance belt 10. In this case, even if ink droplets are ejected from the nozzle row 7-5 when the predetermined number of timing signal pulses are counted from the state (a), the recording dots recorded by the nozzle row 7-1 are recorded. The positions of 20a and the recording dots 20b recorded by the nozzle row 7-5 are shifted. Therefore, the quality of the recorded image obtained is low. That is, when the amount of movement of the conveyor belt 10 per pulse is small, the recording position is shifted as shown in FIG. 7C, and when the amount of movement of the conveyor belt 10 per pulse is large, (d The recording position is shifted as shown in FIG.

The deviation amount of the image recording position due to the thickness or the like of the conveyor belt 10 exhibits a characteristic as shown by a curve a in FIG. 6 that is repeated in a cycle in which the conveyor belt 10 makes one round.
In FIG. 6, the horizontal axis indicates the amount of displacement from the starting position of the conveyor belt 10, and the vertical axis indicates the amount of deviation of the image position.

  Such image recording misregistration can be eliminated by shifting the recording timing in a direction opposite to the direction of the misregistration. In other words, if the recording timing is corrected so as to have the characteristics as shown by the curve b in FIG. 6, the image recording misalignment can be eliminated.

  For example, when the thickness unevenness of the transport belt 10 is substantially constant within the same production lot, the speed unevenness (change in image recording position deviation) is first measured for one transport belt 10 extracted from the production lot. . If correction characteristic data representative of the production lot is calculated based on the measurement result, correction can be substantially corrected by using the correction data in common for the other conveyor belts 10 in the same production lot. it can.

  As described above, the image recording apparatus 1 according to the present embodiment can perform high-quality image recording by matching the image recording positions of the images without using dedicated correction information for each transport mechanism 8.

  However, there are variations in the conveyor belt 10 within the same production lot, and if the fine adjustment is made centering on this correction characteristic, the positional deviation correction of the image recording may be further improved. In this fine adjustment, a plurality of correction characteristics with slight changes in phase and amplitude are prepared in advance with reference to the correction characteristics that represent the same production lot, and the most suitable correction characteristics can be easily measured. If a selection is made based on the result, it is not necessary to use a full-scale measuring machine.

Next, a procedure for obtaining appropriate correction parameters for each of the correction units 5 (5-1 to 5-12) will be described.
As described above, the image recording position is corrected using the first color image recording position as a reference and correcting the reference position to set the image recording positions of the second and subsequent colors. Here, as an example, a procedure for obtaining an appropriate correction parameter for setting the image recording position of the second color will be described. The correction of the timing signals for the second color nozzle rows 7-5 to 7-8 is performed by the correction units 5-1 to 5-4 as described above.

  First, as candidates for appropriate correction parameters representing the correction characteristics of the conveyance belt 10 of the same production lot, the phases of the respective waveforms as shown in FIGS. 7A, 7B, 7C, and 7D are slightly changed. Correction parameters that are shifted one by one are prepared in advance. After that, an optimal one of the correction parameter candidates is selected by a procedure according to the flowchart shown in FIG.

  First, in step 11, the control unit 2 performs a process of temporarily setting the correction parameter candidates in the correction units 5-1 to 5-4. Here, the correction parameter in FIG. 7A is set in the correction unit 5-1, the correction parameter in FIG. 7B is set in the correction unit 5-2, and the correction parameter in FIG. 7C is set in the correction unit 5-3. The correction parameters in FIG. 7D are set in the correction unit 5-4.

  Next, in step 12, in response to a predetermined instruction input by the user operating the input unit 19, the control unit 2 performs a process of controlling the image recording apparatus 1 to record a test pattern on the recording medium 17.

  As a test pattern to be recorded on the recording medium 17 by this processing, a pattern that can easily identify the recording position deviation of the image is used. Specifically, for example, as shown in FIG. 9, a pattern that draws a plurality of horizontal lines in the transport direction at the same position at the same position in both the first color and the second color is used. be able to. In this test pattern, when the image recording position is shifted, the first color line and the second color line are separated and appear as two lines, so that the occurrence of the image recording position shift can be easily recognized. it can.

  In order to grasp the occurrence state of the image recording position deviation for one rotation of the conveyance belt 10, a test pattern is used so that the recording position deviation can be found in a range corresponding to one rotation of the conveyance belt 10. It is desirable to record images. For example, if the length of the recording medium 17 is 420 mm and the length of one circumference of the conveying belt 10 is 1200 mm, 2 <1200/420 ≦ 3, and therefore, three test patterns are recorded in succession. Is desirable.

  Next, in step 13, the image recording position deviations from the first recording row to the fourth recording row of the test pattern recorded as described above are compared with each other, and the recording row with the smallest image recording position deviation is obtained. Select based on the result of the comparison. This comparison / selection may be performed visually, or may be performed using a well-known image measurement technique. Then, the correction parameter set to the correction unit 5-1 to 5-4 that has been corrected for the selected recording row is selected. The result of this selection is acquired by the input unit 19 when the user operates the input unit 19 and sent to the control unit 2.

  Of the correction characteristic waveforms shown in FIGS. 7A to 7D, it is assumed that the waveform of FIG. 7B has the closest phase relationship to the correction characteristic waveform shown in FIG. 6. In this case, the recording on the recording medium 17 by the nozzle array 7-6 for which the timing signal is corrected by the correction unit 5-2 that has set the correction parameters in FIG. The deviation should be the least. Therefore, in this case, the correction parameter shown in FIG. 7B, which is the basis of the correction of the timing signal for the second recording row with the smallest positional deviation of the test pattern image, is selected.

  Next, at step 14, the control unit 2 selects the correction parameters (in this case, the figure) for all of the four correction units 5-1 to 5-4 respectively corresponding to the first to fourth recording rows. A process for setting a correction parameter exhibiting a correction characteristic of 7B is performed. In this way, it is possible to record an image with little image recording position shift not only in the second recording row but also in all of the first to fourth recording rows.

According to the procedure according to the flowchart shown in FIG. 8, the optimum parameter for the phase of the waveform is selected from the correction parameters corresponding to the correction characteristics shown in FIGS. 7A to 7D.
Next, a method for adjusting the amplitude (the magnitude of the correction amount of deviation) in the correction characteristic selected as described above will be described.

  First, as in the case of the selection procedure of the correction characteristics having the optimum phase relationship described above, appropriate correction parameter candidates representing the correction characteristics for the transport belt 10 of the same production lot are prepared in advance. Note that here, as appropriate correction parameter candidates, correction parameters for a waveform in which the amplitude of each correction characteristic is slightly shifted as illustrated in FIGS. 10A, 10B, 10C, and 10D are prepared. To keep.

  The phase of these waveforms is the same as the phase of the waveform of the correction characteristic corresponding to the correction parameter selected by the procedure shown in FIG. Therefore, in the present embodiment, for each of the four correction characteristics having different waveform phases shown in FIGS. 7A to 7D, four corrections having the same waveform phase and different amplitudes are shown in FIGS. 10A to 10D. Correction parameters corresponding to the characteristics are prepared in advance. That is, in this embodiment, a total of 16 correction parameters are prepared in advance.

  As described above, after preparing the correction parameters corresponding to the correction characteristics shown in FIGS. 10A to 10D, the optimum correction parameter candidates are obtained by the procedure according to the flowchart shown in FIG. 11. Selected. The procedure shown in FIG. 11 is very similar to the procedure shown in FIG.

  First, in step 21, the control unit 2 performs a process of temporarily setting the correction parameter candidates in the correction units 5-1 to 5-4. Here, the correction parameter in FIG. 10A is set in the correction unit 5-1, the correction parameter in FIG. 10B is set in the correction unit 5-2, and the correction parameter in FIG. 10C is set in the correction unit 5-3. The correction parameters shown in FIG. 10D are set in the correction unit 5-4.

  Next, in step 22, in response to a predetermined instruction input by the user operating the input unit 19, the control unit 2 performs a process of controlling the image recording apparatus 1 to record a test pattern on the recording medium 17. As a test pattern to be recorded on the recording medium 17 by this processing, for example, the same test pattern as that recorded on the recording medium 17 in step 12 in the procedure shown in FIG. 7 can be used.

  Next, in step 23, the image recording position deviations from the first recording row to the fourth recording row of the test pattern recorded as described above are compared with each other, and the recording row with the smallest image recording position deviation is obtained. Select based on the result of the comparison. This comparison / selection may be performed visually, or may be performed using a well-known image measurement technique. Then, the correction parameter set to the correction unit 5-1 to 5-4 that has been corrected for the selected recording row is selected. The result of this selection is acquired by the input unit 19 when the user operates the input unit 19 and sent to the control unit 2.

  10A to 10D, it is assumed that the waveform of FIG. 10C has the closest relationship between the waveform of the correction characteristic illustrated in FIG. 6 and the amplitude. In this case, the recording on the recording medium 17 by the nozzle array 7-7 whose timing signal has been corrected by the correction unit 5-3 that has set the correction parameters in FIG. 10C is the position of the image of the test pattern. The deviation should be the least. Therefore, in this case, the correction parameter shown in FIG. 10C, which is the basis of the correction of the timing signal for the third recording row in which the positional deviation of the test pattern image is the smallest, is selected.

  Next, at step 14, the control unit 2 selects the correction parameters (in this case, the figure) for all of the four correction units 5-1 to 5-4 respectively corresponding to the first to fourth recording rows. A process of setting a correction parameter exhibiting a correction characteristic of 10C) is performed. In this way, it is possible to record an image with little image recording position shift not only in the third recording row but also in all of the first to fourth recording rows.

  Through the procedure according to the flowchart shown in FIG. 11, the optimum parameter for the amplitude of the waveform is selected from the correction parameters corresponding to the correction characteristics shown in FIGS. 10A to 10D.

  Thus, appropriate correction parameters are obtained for each of the correction units 5-1 to 5-4. For the correction units 5-5 to 5-12, correction parameters appropriate for setting the image recording positions of the third color and the fourth color are set to be appropriate for setting the image recording positions of the second color described above. The correction parameter is obtained in the same manner as the acquisition of the correction parameter. If the color of each color is different, even if the test pattern is recorded on the recording medium 17 in parallel, the recording row is selected even when the test pattern image has the smallest positional deviation. It is possible.

  The correction unit 5 (5-1 to 5-12) corrects the frequency of the timing signal corresponding to the belt position L acquired according to the timing control program 4 with reference to the appropriate correction parameter obtained in this way. Find the amount. Then, the frequency of the input timing signal is changed according to the obtained correction amount. Thus, the image recording position shift is eliminated, and high-quality image recording can be performed.

  In this embodiment, the optimum one is selected from the 16 correction parameters prepared in advance. Instead, if necessary, more correction parameters are prepared in advance, and, for example, the selection for the phase and the selection for the amplitude are performed in two stages in the same manner as described above. The optimum correction parameter may be selected from the correction parameters. Further, the user may add a new correction parameter from the input unit as necessary.

  As described above, according to this embodiment, the image recording apparatus 1 can be assembled even if the belt speed fluctuation of the conveyor belt 10 is not measured in advance for each conveyor mechanism 8 using a dedicated measuring instrument or the like. In such a state, it is possible to correct the periodic speed fluctuation. Further, not only in the initial state after manufacture and shipment of the image recording apparatus 1 but also after a change with time, the correction parameter selection operation can be performed at that time to appropriately correct the speed fluctuation.

  In the above description, it has been described that the image recording misregistration is caused by the non-uniformity of the thickness of the conveyor belt 10, but if this misregistration is periodic, the image recording position according to the present embodiment. Deviation correction is possible.

  In addition, this invention is not limited to embodiment mentioned above, In the implementation stage, it can change variously in the range which does not change the summary.

1 is a diagram illustrating a configuration of an image recording apparatus according to an embodiment of the present invention. It is a figure which shows the example of arrangement | positioning of each component of the image recording device which concerns on embodiment of this invention. It is a figure which shows the arrangement configuration of a nozzle row. It is a figure which shows the example of a correction table. FIG. 6 is a diagram schematically illustrating a state in which nozzles for a first color and a second color eject ink droplets and record dots on a recording medium. FIG. 6 is a diagram illustrating a characteristic of a deviation amount of an image recording position due to a thickness of a conveyance belt and an optimum correction characteristic. It is a figure which shows the 1st example of the candidate of the correction parameter from which a phase differs. It is a figure which shows the 2nd example of the candidate of the correction parameter from which a phase differs. It is a figure which shows the 3rd example of the candidate of the correction parameter from which a phase differs. It is a figure which shows the 4th example of the candidate of the correction parameter from which a phase differs. It is a flowchart which shows the procedure which selects the correction parameter which is optimal about the phase of the waveform of a correction characteristic. It is a figure which shows the example of a test pattern. It is a figure which shows the 1st example of the candidate of the correction parameter with the same phase and different amplitude. It is a figure which shows the 2nd example of the candidate of the correction parameter with the same phase and different amplitude. It is a figure which shows the 3rd example of the candidate of the correction parameter with the same phase and different amplitude. It is a figure which shows the 4th example of the candidate of the correction parameter which has the same phase and different amplitude. It is a flowchart which shows the procedure which selects the correction parameter which is optimal about the newspaper of the waveform of a correction characteristic.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image recording device 2 Control part 3 Memory | storage part 4 Timing control program 5,5-1 thru | or 5-M correction | amendment part 6,6-1 thru | or 6-N Nozzle row drive part 7,7-1 thru | or 7-N Nozzle row 8 Conveying mechanism 9 Driving unit 10 Conveying belt 11 Conveying information generating unit 12 Starting point mark 13 Starting point detecting unit 14 Host device 15 Driving roller 16 Driven roller 17 Recording medium 18 Timing control unit 19 Input unit 20a, 20b Recording dot

Claims (18)

Detecting a starting point of a conveying belt that conveys the placed recording medium to generate starting point detection information, and generating a conveying mechanism that generates conveying information of the recording medium, and a nozzle array including a plurality of nozzles. A plurality of recording units having a plurality of recording units in a direction orthogonal to the transport direction of the recording medium, and ejecting ink from the nozzle rows of the recording units in the process of transporting the recording medium. In the image recording apparatus that performs the recording process,
A storage unit that stores correction parameters respectively associated with the nozzle rows of the plurality of recording units, the correction parameters for correcting the timing of ejecting the ink to the nozzle rows;
An input unit for selecting and setting the correction parameter;
A plurality of correction units that correct the timing of ejecting the ink from the nozzle row for each nozzle row based on the starting point detection information and the conveyance information and the correction parameter selected by the selection input; An image recording apparatus comprising: at least a control unit including at least a recording timing control unit that performs control for ejecting the ink from the nozzle row at a timing corrected by the correction unit.   The value of the correction parameter is for reducing a shift in the recording position that occurs when the recording process is performed, and is a representative value that is commonly used when the conveyor belt is the same production lot. The image recording apparatus according to claim 1, wherein the image recording apparatus is provided.   The number M of the correction units is M = (X−1) × Y, where X is the number of the recording units and Y is the number of the nozzle rows per recording unit. Item 8. The image recording apparatus according to Item 1.   The control unit includes at least an arithmetic processing unit and a storage unit that stores a control program in advance, and functions as the recording timing control unit by causing the arithmetic processing unit to execute the control program. The image recording apparatus according to claim 1, wherein: The storage unit stores a plurality of correction parameter candidates in advance,
The image recording apparatus according to claim 1, wherein the input unit acquires an input for selecting the correction parameter from a plurality of correction parameter candidates stored in the storage unit. The input unit further acquires an input of a test pattern recording process instruction,
2. The control unit according to claim 1, wherein when the input of the instruction is acquired, the control unit controls the image recording apparatus to perform recording processing of an image of a predetermined test pattern on the recording medium. The image recording apparatus described in 1.   When the control unit causes the test pattern image to be recorded on the recording medium, the recording timing control unit is configured to perform a plurality of correction parameter candidates stored in the storage unit. The image recording apparatus according to claim 6, wherein the ink is ejected from the nozzle row at a timing corrected by a correction unit. Detecting a starting point of a conveying belt that conveys the placed recording medium to generate starting point detection information, and generating a conveying mechanism that generates conveying information of the recording medium, and a nozzle array including a plurality of nozzles. A plurality of recording units having a plurality of recording units in a direction orthogonal to the transport direction of the recording medium, and ejecting ink from the nozzle rows of the recording units in the process of transporting the recording medium. A method for controlling an image recording apparatus that performs recording processing on
The image recording apparatus includes correction parameters respectively associated with the nozzle rows of the plurality of recording units, the correction parameters for correcting the timing at which the ink is ejected to the nozzle rows. Remembering the memory part that is stored,
An input unit provided in the image recording apparatus obtains an input for selecting the correction parameter;
A timing at which the correction unit provided in the image recording apparatus ejects the ink from the nozzle row based on the starting point detection information, the conveyance information, and a correction parameter selected by the selection input. Correct every time,
An image recording device comprising: a recording timing control unit provided in the image recording apparatus, wherein the ink ejection is ejected from the nozzle row at a timing corrected by the correction unit. Control method of the device.   The value of the correction parameter is for reducing a shift in the recording position that occurs when the recording process is performed, and is a representative value that is commonly used when the conveyor belt is the same production lot. The method of controlling an image recording apparatus according to claim 8, wherein:   The number M of the correction units is M = (X−1) × Y, where X is the number of the recording units and Y is the number of the nozzle rows per recording unit. Item 9. A method for controlling an image recording apparatus according to Item 8. The storage unit stores a plurality of correction parameter candidates in advance,
The image recording apparatus control method according to claim 8, wherein the input unit acquires an input for selecting the correction parameter from a plurality of correction parameter candidates stored in the storage unit. The input unit further acquires an input of a test pattern recording process instruction,
9. The method according to claim 8, further comprising: controlling the image recording apparatus when acquiring the instruction input to perform recording processing of an image of a predetermined test pattern on the recording medium. A control method of the image recording apparatus described.   When the test pattern image is recorded on the recording medium, the nozzles are corrected at a timing corrected by a plurality of correction units based on different correction parameter candidates stored in the storage unit. The method of controlling an image recording apparatus according to claim 12, comprising discharging the ink from a line. Detecting a starting point of a conveying belt that conveys the placed recording medium to generate starting point detection information, and generating a conveying mechanism that generates conveying information of the recording medium, and a nozzle array including a plurality of nozzles. A plurality of recording units having a plurality of recording units in a direction orthogonal to the transport direction of the recording medium, and ejecting ink from the nozzle rows of the recording units in the process of transporting the recording medium. A program for causing an arithmetic processing unit to control an image recording apparatus that performs recording processing on
The image recording apparatus includes correction parameters respectively associated with the nozzle rows of the plurality of recording units, the correction parameters for correcting the timing at which the ink is ejected to the nozzle rows. Storage processing to be stored in the storage unit,
An input process for causing the input unit provided in the image recording apparatus to acquire an input for selecting the correction parameter;
A correction process for correcting the timing at which the ink is ejected from the nozzle row based on the starting point detection information and the conveyance information and the correction parameter selected by the selection input;
A program that causes the arithmetic processing unit to perform control processing for performing control to eject the ink from the nozzle row at the corrected timing.   The value of the correction parameter is for reducing a shift in the recording position that occurs when the recording process is performed, and is a representative value that is commonly used when the conveyor belt is the same production lot. The program according to claim 14, wherein there is a program. The storage process is a process of storing a plurality of correction parameter candidates in the storage unit in advance,
15. The program according to claim 14, wherein the input process is a process for causing the input unit to acquire an input for selecting the correction parameter from a plurality of correction parameter candidates stored in the storage unit. . A process for causing the input unit to further acquire an input of a test pattern recording process;
Controlling the image recording device when the input of the instruction is acquired and causing the arithmetic processing device to perform processing for recording an image of a predetermined test pattern on the recording medium. The program according to claim 14, characterized in that   A plurality of correction units based on different correction parameter candidates stored in the storage unit when causing the arithmetic processing unit to perform processing for recording the test pattern image on the recording medium. 18. The program according to claim 17, wherein the processing unit causes the arithmetic processing unit to perform a process of ejecting the ink from the nozzle row at a timing corrected by the operation.

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