Ink jet recording device, control method, and program

Abstract

To prevent unnecessary replacement of a recording head.SOLUTION: In one embodiment of the invention, an ink jet recording device comprises: a recording head which has a plurality of nozzle rows, in which the plurality of nozzle rows are arranged at different positions in a first direction, and each of the plurality of nozzle rows is configured by a plurality of nozzles that discharge ink and are arranged in a second direction intersecting the first direction; recovery means; second recording region non-discharge determination means which determines, for each nozzle among the plurality of nozzles, whether the nozzle is non-discharging, each nozzle existing in a second recording region having a width larger than that of a first recording medium on which an image recording process is performed; and notification means that, after execution of the second recording region non-discharge determination process by the second recording region non-discharge determination means, notifies of an abnormality of the recording head when the number of non-discharging nozzles existing in the first recording region having the width of the first recording medium determined by the second recording region non-discharge determination means exceeds a predetermined threshold.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to an inkjet printing apparatus, a control method, and a program. [Background technology]

[0002] Inkjet recording devices form images by ejecting ink directly onto a recording medium from minute nozzles. Therefore, if ink or dust such as paper dust adheres to the nozzle surface of the recording head, ink ejection problems may occur. When ink ejection problems occur, streaks or missing lines appear in the recorded product (also called output product), resulting in image defects that are visible to the user.

[0003] To avoid such image defects, a technique has been proposed in which ejection data that would be recorded by a non-ejecting nozzle in a print head is complemented by other nozzles that are capable of ejecting (so-called non-ejection complement technique).

[0004] Patent Document 1 discloses that non-discharge nozzles are detected and supplemented with multiple nozzles on the same scan line, and that an abnormality signal is output when the number of non-discharge nozzles on the same scan line reaches a predetermined threshold.

[0005] Incidentally, one type of inkjet recording device known is a full-line inkjet recording device that arranges multiple full-line inkjet heads in a row across the entire width of the recording medium in the direction of movement of the recording medium, and ejects ink from each head to perform one-pass recording. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-054006 [Patent Document 2] Japanese Patent Application Publication No. 8-309963 [Patent Document 3] Japanese Patent Publication No. 2023-002736 Summary of the Invention [Problem to be solved by the invention]

[0007] However, Patent Document 1 does not take into consideration whether the nozzle in question is a nozzle that exists in a printing area determined according to the size of the printing medium, or a nozzle that exists outside that printing area. Therefore, even if the nozzle in question is not in the printing area (that is, if it is outside the printing area), it will still be counted as a non-ejecting nozzle, which could lead to unnecessary replacement of the print head.

[0008] In view of the above, an object of the present disclosure is to prevent unnecessary replacement of recording heads. [Means for solving the problem]

[0009] One embodiment of the present invention is an inkjet recording apparatus comprising: a recording head having a plurality of nozzle arrays, the plurality of nozzle arrays being arranged at different positions in a first direction, and each of the plurality of nozzle arrays being configured by a plurality of nozzles that eject ink arranged in a second direction that intersects the first direction; a recovery means that makes non-ejecting nozzles included in the plurality of nozzles capable of ejecting, thereby recovering the ejection performance of the recording head; a second recording area non-ejection determination means that determines whether each nozzle included in the plurality of nozzles is non-ejecting after a recovery process has been performed by the recovery means, wherein each nozzle is located in a second recording area that is wider than a first recording medium on which an image recording process is performed; and a notification means that notifies of an abnormality in the recording head if, after the second recording area non-ejection determination process has been performed by the second recording area non-ejection determination means, the number of non-ejecting nozzles present in a first recording area of ​​the width of the first recording medium is determined by the second recording area non-ejection determination means to be greater than a predetermined threshold. [Effects of the Invention]

[0010] According to the present disclosure, unnecessary replacement of the recording head can be prevented. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a schematic perspective view showing the internal configuration of a recording device. [Figure 2] Block diagram showing the configuration of a recording device [Figure 3] Block diagram for explaining non-ejection processing [Figure 4] Flowchart of non-discharge compensation processing [Figure 5] FIG. 1 is a diagram illustrating a recording head; [Figure 6] Diagram showing the priority table [Figure 7] Flowchart of non-discharge detection process during recording [Figure 8] FIG. 10 is a diagram showing the relationship between the inspection pattern, the non-discharge determination region, and the non-discharge number determination region. [Figure 9] Flowchart of pre-recording printhead state determination process [Figure 10] Flowchart of second non-discharge determination process [Figure 11] Flowchart of non-discharge detection process during recording DETAILED DESCRIPTION OF THE INVENTION

[0012] [First embodiment] As an application example of this embodiment, a case where this embodiment is applied to an inkjet recording apparatus using an inkjet full-line head will be described below. Note that the following description will be given taking as an example a high-speed full-line inkjet recording apparatus that uses a continuous sheet wound in a roll (so-called roll paper).

[0013] <Internal structure of the recording device> 1 is a schematic perspective view showing the internal configuration of a recording apparatus 100 according to this embodiment. The recording apparatus 100 includes a paper supply unit 101, a recording unit, and a discharge unit 102.

[0014] The paper supply unit 101 is a unit that can store a continuous sheet wound in a roll as a recording medium, and supplies this continuous sheet to the recording unit.

[0015] The recording unit is a unit that forms an image on a conveyed sheet using a first recording head 105, a second recording head 106, a third recording head 107, and a fourth recording head 108. The recording unit also includes a first conveying roller 103 and a second conveying roller 104 that convey the sheet. In this specification, the first recording head 105, the second recording head 106, the third recording head 107, and the fourth recording head 108 will be collectively referred to simply as "recording heads" when there is no need to particularly distinguish between them.

[0016] The print head is a line-type print head with inkjet nozzle arrays formed over a range covering the maximum width of the sheet expected to be used. The first print head 105, second print head 106, third print head 107, and fourth print head 108 are aligned at different positions in the sheet transport direction (X direction) and parallel to the Y direction. The first print head 105 corresponds to C (cyan), the second print head 106 corresponds to M (magenta), the third print head 107 corresponds to Y (yellow), and the fourth print head 108 corresponds to K (black). The number of print heads and ink colors is not limited to four. For example, a configuration having multiple (two or more) print heads may be used. Alternatively, a configuration having a single elongated print head may be used in which multiple chips each having multiple nozzle arrays perpendicular to the sheet transport direction are arranged in a staggered pattern.

[0017] As the inkjet method, a method using a heat element, a method using a piezoelectric element, a method using an electrostatic element, a method using a MEMS element, etc. C (cyan) ink is supplied to the first print head 105 from an ink tank (not shown) via an ink tube. Similarly, M (magenta) ink, Y (yellow) ink, and K (black) ink are supplied to the second print head 106, the third print head 107, and the fourth print head 108 from their respective ink tanks via their respective ink tubes.

[0018] The discharge unit 102 is a unit that conveys sheets cut by a cutter (not shown) and, as necessary, sorts and discharges printed sheets by group into different discharge trays (not shown). Each of the first, second, third, and fourth print heads 105, 106, 107, and 108 print heads is equipped with a cap to prevent the print head from drying out when not in use. The caps are capped when no printing operation is being performed. These caps are connected to a pump that generates negative pressure, which generates negative pressure while the print heads are capped to suck out ink, thereby performing a print head recovery process. Each of the first, second, third, and fourth print heads 105, 106, 107, and 108 print heads also has a wiper unit that wipes the nozzle surface.

[0019] The reading unit 109 is a unit for reading images such as test patterns printed by the print heads. The reading unit 109 is, for example, a CCD line sensor, and is configured as a two-dimensional image sensor. In the reading unit 109, multiple reading elements are arranged in a direction (nozzle arrangement direction, Y direction) that intersects, for example, orthogonal to, the sheet conveyance direction (+X direction). The reading unit 109 also includes light-emitting elements and the like. The width of the reading unit 109 in the nozzle arrangement direction (Y direction) is set to be equal to or greater than the width of the print heads. By optically reading the test pattern using the reading unit 109 configured in this way, it is possible to inspect the nozzle states of the first print head 105, the second print head 106, the third print head 107, and the fourth print head 108.

[0020] The control unit 110 is a unit that controls the entire recording device 100. The control unit 110 according to this embodiment will be described below with reference to Fig. 2. Fig. 2 is a block diagram showing the configuration of the recording device according to this embodiment.

[0021] 2, the control unit 110 includes a CPU 201, a ROM 202, a RAM 203, an image processing unit 207, an engine control unit 208, and a scanner control unit 209. In addition, an HDD 204, an operation unit 206, an external I / F 205, and the like are connected to the control unit 110 via a system bus 210.

[0022] The CPU 201 is a central processing unit in the form of a microprocessor (microcomputer). The CPU 201 controls the overall operation of the printer by executing programs and activating hardware. The ROM 202 stores programs executed by the CPU 201 and fixed data necessary for various printer operations. The RAM 203 is used by the CPU 201 as a work area and as a temporary storage area for various received data and various setting data. The HDD 204 is a hard disk built into the recording device 100. The HDD 204 stores programs executed by the CPU 201, recording data, and setting information necessary for various operations of the recording device 100, and the CPU 201 can read the written programs, etc. as needed. Note that the HDD 204 may be replaced with another large-capacity storage device.

[0023] The operation unit 206 is an operation unit including hard keys and a touch panel for the user to perform various operations, and a display unit for presenting (notifying) the user with various information. Note that the means for presenting information to the user is not limited to image display on the display unit. For example, information can also be presented to the user by outputting sound (buzzer, voice, etc.) from a sound generator.

[0024] The image processing unit 207 performs image processing and develops (converts) print data (for example, data expressed in a page description language) handled by the printing device 100 into image data (bitmap image). For example, the image processing unit 207 converts the color space (for example, YCbCr) of the image data included in the input print data into a standard RGB color space (for example, sRGB). The image processing unit 207 also performs various image processing on the image data as needed, such as resolution conversion to an effective number of pixels (capable of being recorded by the printing device 100), image analysis, and image correction. The image data obtained by these image processing operations is stored in the RAM 203 or the HDD 204.

[0025] The engine control unit 208 is an ASIC that controls the process of recording an image based on print data on a sheet in response to control commands received from the CPU 201, etc. Specifically, the engine control unit 208 issues ink ejection instructions to the print heads of each color, sets ejection timing to adjust dot positions (ink landing positions) on the print medium, acquires information on the drive status of the print heads, and performs adjustments based on the acquired information. The engine control unit 208 also controls the drive of the print heads based on the print data, causing the print heads to eject ink and form an image on the sheet. The engine control unit 208 also controls the paper feed rollers and transport rollers, such as issuing drive instructions for the paper feed rollers and transport rollers and acquiring information on the rotation status of the paper feed rollers and transport rollers. This allows the engine control unit 208 to transport the sheet at an appropriate speed and route, and to stop printing as necessary.

[0026] The scanner control unit 209 controls the reading unit 109 in response to control commands received from the CPU 201 and the like to read an image on a sheet. As a result, the scanner control unit 209 acquires analog luminance data for red (R), green (G), and blue (B) colors and converts the acquired analog luminance data into digital data. The scanner control unit 209 also issues drive instructions to the image sensor and acquires information about the status of the image sensor based on the drive instructions. The scanner control unit 209 also analyzes the luminance data acquired by the image sensor and performs tasks such as detecting ink mis-ejection from the first print head 105, the second print head 106, the third print head 107, and the fourth print head 108 and detecting the sheet cutting position. For sheets determined by the scanner control unit 209 to have an image correctly recorded, a drying process is performed to dry the ink on the sheet, and the sheet is then ejected to a designated tray of the sorting unit.

[0027] <Non-discharge treatment> 3 is a block diagram showing the functional configuration of the engine control unit 208. In more detail, this is a diagram for explaining the process of detecting non-ejecting nozzles, which is primarily performed by the engine control unit 208, and using other nozzles to supplement the ejection data corresponding to the detected non-ejecting nozzles (this series of processes is defined as the "non-ejection process"). In this embodiment, non-ejecting nozzles include nozzles that do not eject any ink at all, as well as nozzles that eject ink but in a curved direction (defective nozzles), and nozzles that eject ink but in a small amount (poor nozzles).

[0028] 3, a receiving buffer 302, a non-discharge information buffer 303, and a recording buffer 304 are secured as partial areas of a main memory such as a DRAM that constitutes the RAM 203. The receiving buffer 302 stores image data to be recorded (referred to as input image data) that is sent by a host computer (hereinafter, host PC) 211 and received via a receiving I / F 301. Hereinafter, this input image data will be described as being quantized image data for each ink color.

[0029] The ejection data generation unit 305 reads the quantized input image data from the receiving buffer 302, and generates ejection data for each nozzle array mounted on the print head based on the input image data. For example, if the print head has eight nozzle arrays, ejection data is generated for each of the eight nozzle arrays. The ejection data expresses whether each nozzle is ejecting or not, for example, ejection can be expressed by "1" and non-ejection by "0". Below, we will explain an example where the ejection data is expressed as two values ​​(1 or 0).

[0030] The reading result acquisition unit 306 acquires the reading results of the test pattern acquired by the scanner control unit 209 using the reading unit 109, and transmits the acquired reading results to the non-discharge information derivation unit 307. The non-discharge information derivation unit 307 analyzes the reading results transmitted by the reading result acquisition unit 306 and identifies the non-discharge nozzle. Identification information (referred to as non-discharge information) of the identified non-discharge nozzle is written to the non-discharge information buffer 303.

[0031] The discharge failure complement processing unit 308 is made up of an ejection data holding unit 309, a discharge failure information reading unit 310, a complement destination candidate selection unit 311, a complement priority determination unit 312, a priority information holding unit 313, and a complement processing unit 314. The discharge failure complement processing unit 308 performs discharge failure complement processing on the ejection data for each nozzle array, and then writes the ejection data that has undergone the discharge failure complement processing to the recording buffer 304.

[0032] The printhead control unit 315 reads the ejection data that has been written to the print buffer 304 and has undergone ejection failure complement processing, and transmits the read ejection data that has undergone ejection failure complement processing to the printhead 318. The printhead control unit 315 drives the printhead 318 based on the ejection data that has undergone ejection failure complement processing, and records an image on the sheet. At this time, the print timing generation unit 316 measures the amount of movement of the sheet based on the pulse signal of the encoder 317, and the printhead control unit 315 generates a signal for controlling the printhead based on the measurement result and transmits it to the printhead 318 as a drive signal.

[0033] <Discharge failure compensation processing> The discharge failure complement processing included in the above-mentioned discharge failure processing will be explained below with reference to Fig. 4. Fig. 4 is a flowchart of the control flow of the discharge failure complement processing according to this embodiment. The discharge failure complement processing unit 308 (Fig. 3) performs discharge failure complement processing in accordance with the control flow of Fig. 4. The processing of Fig. 4 is started when the amount of discharge data generated by the discharge data generation unit 305 reaches a predetermined threshold value.

[0034] In step S401, the ejection data holding unit 309 receives the ejection data generated by the ejection data generating unit 305 and holds the received ejection data. Note that "step S~" will be abbreviated as "S~" hereinafter.

[0035] In S402, the discharge failure information reading unit 310 reads out the discharge failure information stored in the discharge failure information buffer 303, and holds the read discharge failure information.

[0036] In S403, the discharge failure complement processing unit 308 determines whether there are any nozzles to be complemented based on the discharge data held in S401 and the discharge failure information held in S402. In other words, it determines whether the nozzles assigned "1" in the discharge data include any discharge failure nozzles indicated by the discharge failure information. If the determination result in this step is true, the process proceeds to S404. On the other hand, if the determination result in this step is false, the discharge failure complement processing ends.

[0037] In S404, the complement candidate selection unit 311 moves the ejection data ("1" data) corresponding to the complement target nozzle to the complement destination according to the priority. In other words, the "1" data is converted into ejection data ("1" data) corresponding to the complement destination nozzle. More specifically, the complement candidate selection unit 311 first selects a nozzle that satisfies a predetermined condition as a candidate for the complement target nozzle based on the ejection data stored in S401 and the non-ejection information stored in S402. The predetermined condition is that the nozzle is not a non-ejection nozzle and is not assigned the "1" data. If there are multiple nozzles that satisfy the predetermined condition, the complement priority determination unit 312 reads out the priority information stored in the priority information storage unit 313 and notifies the complement processing unit 314 of the read priority information. If there is only one candidate for the complement target nozzle, the complement processing unit 314 assigns the ejection data ("1" data) that was assigned to the complement target nozzle to that single nozzle. On the other hand, if there are multiple candidates for the complement target nozzle, the priority information notified by the priority information storage unit 313 is used to determine the one with the highest priority from among the multiple candidates. Then, the ejection data ("1" data) assigned to the complement target nozzle is assigned to this determined nozzle. Note that if the ejection data ("1" data) assigned to the complement target nozzle is assigned to a nozzle other than the complement target nozzle, the ejection data ("1" data) is deleted. Furthermore, if there is no nozzle that meets the predetermined conditions, the complement target candidate selection unit 311 notifies the CPU 201 that the complement process cannot be performed because there are no candidates. When the complement process has been completed for all complement target nozzles, the process proceeds to S405.

[0038] In S405, the complementation processing unit 314 writes the ejection data acquired by the processing in S404 into the print buffer 304.

[0039] The printhead according to this embodiment will now be described with reference to FIG. 5. The first printhead 105, second printhead 106, third printhead 107, and fourth printhead 108 have the same configuration. In this example, as shown in FIG. 5, the printhead has multiple chips arranged in the Y direction, and each chip has eight nozzle rows. The nozzles constituting the nozzle rows are arranged at a pitch of 1200 dpi in the Y direction. The length of the printhead in the Y direction is A2 width (420 mm). In this example, the nozzle rows in each of the multiple chips are tilted by several degrees from the Y direction, but this configuration is not limited thereto, and the nozzle rows may extend parallel to the Y direction.

[0040] Next, the priority table held in the priority information holding unit 313 will be described with reference to Fig. 6. The numerical values ​​held in the table shown in Fig. 6 indicate priorities, and the priorities indicate which of columns 1 to 8 is to be used preferentially for completion for each of lines 0 to 7 that are positioned differently in the X direction. Note that this table is based on eight lines in the X direction and is repeated in the column direction.

[0041] <Detection of non-discharge during recording> The non-discharge detection process executed during image recording (referred to as non-discharge detection process during recording) according to this embodiment will be explained below with reference to Fig. 7. Fig. 7(a) is a flowchart of the non-discharge detection process during recording. Note that the explanation will be given here taking as an example a case where an A4-width image is recorded on an A4-width sheet.

[0042] In S701, the engine control unit 208 executes image recording processing. Specifically, the engine control unit 208 controls the recording head control unit 315 to record an image based on the input image data on a sheet. In this example, the images to be recorded are multiple page images, and a test pattern as one page image is recorded each time a predetermined number of page images out of the multiple page images are recorded.

[0043] In S702, the engine control unit 208 executes a first discharge failure determination process. The first discharge failure determination process (S702) will now be described with reference to FIG.

[0044] In S7021, the engine control unit 208 controls the printhead control unit 315 to print a first test pattern on a sheet. At this time, the width of the printed first test pattern is set equal to the Y-direction length of the sheet printed in S701. This area spanning the Y-direction length of the sheet is referred to as the "first printing area" or "sheet width area" (see FIG. 8). Note that image data of the test pattern is stored in the ROM 202 in advance, and the image data of the test pattern for the first printing area is read out to the receive buffer 302 of the RAM 203 and sent to the ejection data generation unit 305.

[0045] In S7022, the engine control unit 208 controls the reading unit 109 to read the first test pattern recorded in S7021.

[0046] In S7023, the discharge failure information deriving unit 307 derives discharge failure information based on the read result in S7022.

[0047] In S7024, the non-discharge information derivation unit 307 writes the non-discharge information derived in S7023 to the non-discharge information buffer 303. After this step is completed, the process proceeds to S703. As described above with reference to FIG. 4, by writing the non-discharge information to the non-discharge information buffer 303, non-discharge complementation processing can be implemented as a subsequent process. By executing the non-discharge complementation processing, even if a non-discharge occurs during printing, it is possible to suppress image defects such as streaks and unevenness caused by the non-discharge.

[0048] Returning to the explanation of Figure 7(a), if the number of non-discharge nozzles determined to be non-dischargeable in the first non-discharge determination process is too large, image defects may be visible in the output even if non-discharge complementation processing is performed. Therefore, in S703, the engine control unit 208 determines whether the number of non-discharge nozzles present in the first recording area (see Figure 8) described above is equal to or greater than a predetermined threshold, based on the non-discharge information written to the non-discharge information buffer 303 in S7024. If the determination result in this step is true, the process proceeds to S704. On the other hand, if the determination result in this step is false, the process returns to S701.

[0049] In S704, the engine control unit 208 suspends the image recording process executed in S701.

[0050] In S705, the engine control unit 208 executes a recovery process to restore the ejection performance of the print head. This recovery process can restore non-ejecting nozzles to an ejection-enabled state. The recovery process executed in S705 may be a recovery process commonly used in the field of inkjet printing devices. For example, this may be a suction process in which the nozzles are capped and negative pressure is applied to the cap to suck ink from the nozzles, or a wiping process in which paper dust and ink adhering to the nozzle surface are wiped off with a wiper made of rubber or nonwoven fabric. Another possible method is a preliminary ejection process in which thickened ink in the nozzles is ejected onto the paper surface by the cap. Furthermore, two or more of these may be combined. After this step is completed, the process proceeds to S706.

[0051] In S706, the engine control unit 208 executes a second discharge failure determination process. This second discharge failure determination process is executed for the purpose of checking whether or not the discharge failure nozzle has recovered in S705.

[0052] The second ejection failure determination process (S706) will now be described with reference to FIG. 7C. In S7061, the engine control unit 208 controls the printhead control unit 315 to print a second test pattern on a sheet. In the second ejection failure determination process, ejection failure information for the entire Y-direction area of ​​the printhead is to be derived. Therefore, the width of the second test pattern printed in this step is set equal to the Y-direction length of the printhead (printhead width). This area spanning the Y-direction length of the printhead is referred to as the "second print area" or "printhead width area" (see FIG. 8). Image data of the test pattern is pre-stored in the ROM 202, and the image data of the test pattern for the second print area is read into the receive buffer 302 of the RAM 203 and transmitted to the ejection data generation unit 305. The reason for printing the second test pattern of the printhead width in this step is to avoid image defects due to ejection failures when printing on a sheet of a different size than the sheet used in the image printing process. It should be noted that the width of the sheet used for recording in this step should be equal to or greater than the width of the recording head, but in this example, the second test pattern is recorded on an A2-width sheet.

[0053] In S7062, the engine control unit 208 controls the reading unit 109 to read the second test pattern recorded in S7061.

[0054] In S7063, the discharge failure information deriving unit 307 derives discharge failure information based on the reading result in S7062.

[0055] In S7064, the discharge failure information derivation unit 307 writes the discharge failure information derived in S7063 into the discharge failure information buffer 303. After this step is completed, the process proceeds to S707.

[0056] In S707, the engine control unit 208 determines whether the number of non-discharge nozzles present in the first recording area (see FIG. 8) described above is equal to or greater than a predetermined threshold, based on the non-discharge information written to the non-discharge information buffer 303 in S7064. If the determination result in this step is true, it is deemed that recovery by the recovery process (S705) is difficult, and the process proceeds to S709. On the other hand, if the determination result in this step is false, it is deemed that a certain number or more of non-discharge nozzles have been recovered by the recovery process (S705), and as a result, it is now possible to avoid image defects such as streaks and unevenness caused by non-discharge, and the process proceeds to S708.

[0057] In S708, the engine control unit 208 resumes the image recording process interrupted in S704. After S708, the process returns to S701.

[0058] In S709, the engine control unit 208 notifies the CPU 201 of the abnormality in the print head, and upon receiving the notification, the CPU 201 notifies the user that the print head is in an abnormal state via the operation unit 206. For example, the CPU 201 may display a message indicating that the print head is in an abnormal state on a display unit that constitutes the operation unit 206. Upon seeing such a message, the user may be able to determine that the print head is in an abnormal state and request that the print head be replaced or checked by a service technician.

[0059] FIG. 8 shows the relationship between the test pattern recorded for the non-discharge determination process, the target area for the non-discharge determination process (referred to as the non-discharge determination area), and the target area for the non-discharge number determination (referred to as the non-discharge number determination process). Symbol (a) in FIG. 8 indicates the first test pattern, and symbol (b) indicates the second test pattern. Symbol (1) in FIG. 8 indicates the width of the area (first non-discharge determination area) where the non-discharge determination process is executed in S702 (first non-discharge determination process), which in this example is the Y-direction length of the first recording area, specifically the A4 width. Symbol (2) indicates the width of the area (non-discharge number determination area) where the non-discharge number determination process is executed in S703, which in this example is the A4 width, similar to the width of the area where the first non-discharge determination process is executed.

[0060] The width of the area (second non-discharge judgment area) judged to be non-dischargeable in the second non-discharge judgment process (S706) is the print head width, as shown by reference symbol (3), and in this example, is A2 width. Meanwhile, the width of the area taken into consideration when judging in S707 whether the number of non-dischargeable nozzles is equal to or greater than a predetermined threshold is A4 width, as shown by reference symbol (4). For areas other than A4 width, as shown by reference symbol (5), no non-discharge number judgment is performed and only non-discharge processing is performed. The reason for this is that even if there are non-dischargeable nozzles outside the first printing area, which is the area of ​​the sheet width currently being printed, this does not affect the image quality of the output, and therefore counting the number of non-dischargeable nozzles including those outside this area would lead to unnecessary replacement of the print head.

[0061] <Effects of this embodiment> As described above, in this embodiment, when determining whether a print head is malfunctioning by determining whether it is malfunctioning during image recording, the area for counting the number of malfunctioning nozzles is limited to the first printing area, which is the area of ​​the sheet width being printed in the image recording process. This prevents the print head from being determined to be malfunctioning by taking into account malfunctioning nozzles in an area that does not affect the image quality of the output of the image recording process, and prevents unnecessary print head replacement. This prevents increased costs and downtime for users due to unnecessary print head replacement.

[0062] [Second embodiment] In this embodiment, before executing the image recording process, a second non-discharge determination process is executed, and based on information about the image width of the image data to be recorded in the image recording process, it is determined whether or not a defect will occur in the output image to be recorded. According to this embodiment, if a defect occurs, the image recording process is not executed, so it is possible to prevent unnecessary recording. Note that the following explanation will mainly focus on differences from the first embodiment. Contents similar to those in the first embodiment will be omitted as appropriate by using the same reference numerals, etc.

[0063] 9 is a flowchart of the pre-recording printhead state determination process according to this embodiment. The pre-recording printhead state determination process is executed before the image recording process is executed. In addition, the second ejection failure determination process (S706 in FIG. 7A) described above is executed at any timing before the pre-recording printhead state determination process.

[0064] In S901 , the engine control unit 208 of the recording device 100 receives image data sent by the host PC 211 via the reception I / F 301 and stores the received image data in the reception buffer 302 .

[0065] In S902, the engine control unit 208 derives the nozzle area to be used when printing the image data stored in the receive buffer 302 in S901. This area is referred to as the "third printing area" or "used nozzle area." The third printing area can be derived based on the width of the image represented by the image data.

[0066] In S903, the engine control unit 208 determines whether the number of non-discharge nozzles present in the third recording area, among those determined to be non-discharge nozzles in the second non-discharge determination process executed before the process of Fig. 9, is equal to or greater than a predetermined threshold. If the determination result in this step is true, the process proceeds to S904. On the other hand, if the determination result in this step is false, the process assumes that the image defects such as streaks and unevenness caused by non-discharge can be avoided, and the process proceeds to S908.

[0067] In S904, the engine control unit 208 executes recovery processing for the print head.

[0068] In S905, the engine control unit 208 executes the second discharge failure determination process (see FIG. 7(c)).

[0069] In S906, the engine control unit 208 determines whether the number of non-discharge nozzles in the third printing area that were determined to be non-dischargeable in the second non-discharge determination process executed in S905 is equal to or greater than a predetermined threshold. If the determination result in this step is true, it is assumed that the recovery process (S904) was executed but the print head could not be recovered, and the process proceeds to S907. On the other hand, if the determination result in this step is false, it is assumed that the state is such that image defects such as streaks and unevenness due to non-discharges can be avoided, and the process proceeds to S908.

[0070] In S907, the engine control unit 208 notifies the CPU 201 of the abnormality in the print head, and upon receiving the notification, the CPU 201 notifies the user that the print head is in an abnormal state via the operation unit 206. For example, the CPU 201 may display a message indicating that the print head is in an abnormal state on a display unit that constitutes the operation unit 206. Upon seeing such a message, the user may be able to determine that the print head is in an abnormal state and request that the print head be replaced or checked by a service technician.

[0071] In S908, the engine control unit 208 starts image recording processing based on the image data stored in the receiving buffer 302 in S901.

[0072] <Effects of this embodiment> As described above, in this embodiment, when determining whether an image defect will occur in the image to be printed based on the results of non-discharge detection performed before image printing, the nozzle area actually used (active nozzle area) is taken into consideration. That is, it is determined whether the number of non-discharge nozzles present in the active nozzle area is equal to or greater than a predetermined threshold, and based on the determination result, it is determined whether the print head is in an abnormal state. This configuration avoids determining that the print head is abnormal by taking into account non-discharge nozzles present in an area that does not affect the image quality of the output, and prevents unnecessary print head replacement. This prevents increased costs and downtime for the user due to unnecessary print head replacement.

[0073] In the above-described case, the second non-discharge determination process is executed in S905, but the non-discharge determination process executed in S905 is not limited to the second non-discharge determination process. Instead of the second non-discharge determination process, the first non-discharge determination process described in the first embodiment, which determines whether a discharge has occurred in the first recording area, may be executed.

[0074] [Other embodiments] The first test pattern printed in S7021 and the second test pattern printed in S7061 have been described as being the same pattern, but with different widths (lengths in the Y direction). However, the first test pattern and the second test pattern may be different patterns. For example, the first test pattern printed in the first discharge failure determination process executed during image recording requires high-speed reading, so a solid pattern that is read at low resolution may be used. On the other hand, the second test pattern printed in the second discharge failure determination process is printed by temporarily halting image recording and does not require high-speed reading, so a pattern that can be read at high resolution and that can identify the position of discharge failure nozzles in detail may be used.

[0075] Furthermore, with regard to non-discharge detection in the first non-discharge judgment process or the second non-discharge judgment process, a form has been described in which a test pattern is recorded on a recording medium and non-discharge information is derived based on the results of reading the recorded test pattern with the reading unit 109, but the present invention is not limited to this form. Another form of the first non-discharge judgment process or the second non-discharge judgment process is, for example, the process shown in FIG.

[0076] As shown in FIG. 10, first, in S1001, the CPU 201 ejects ink onto the cap. In S1002, the CPU 201 detects non-ejecting nozzles by detecting the ejection status of the nozzles using a sensor. The means used in this step may be a means disclosed in Patent Document 2, which ejects ink between a light-emitting element and a light-receiving element and detects whether light emitted from the light-emitting element is blocked by an ink droplet to detect the occurrence of a non-ejection. Furthermore, as the first or second non-ejection determination means, a means disclosed in Patent Document 3 may be used, which includes an electrothermal conversion element that generates ejection energy for ejecting ink from the nozzle and a temperature detection element that detects the temperature of the electrothermal conversion element. In this case, the ejection status of each nozzle (non-ejecting or not) is determined based on the temperature change of the electrothermal conversion element detected by the temperature detection element when ink is ejected from the nozzle, and a non-ejecting nozzle is identified. In S1003, the non-ejection information derivation unit 307 derives non-ejection information based on the detection result of S1002. This step is the same as S7063 (FIG. 7(c)) in the first embodiment. In S1004, the non-discharge information derivation unit 307 writes the non-discharge information derived in S1003 to the non-discharge information buffer 303. This step is the same as S7064 (FIG. 7(c)) in the first embodiment.

[0077] Furthermore, in the above-described embodiment, a form was described in which the ejection data ("1" data) handled by the non-ejecting nozzle is complemented based on the non-ejection information, but the technology disclosed herein can also be applied to a form in which such complementation is not performed.

[0078] Furthermore, in the above embodiment, a form in which recording is performed on roll paper has been described, but the technology of the present disclosure can also be applied to a form in which recording is performed on cut paper.

[0079] Furthermore, in the above-described embodiment, an embodiment has been described in which the image recording process is interrupted if the number of non-discharge nozzles is equal to or greater than a predetermined threshold value while the image recording process is being executed (S701 → S702 → S703 YES → S704 in FIG. 7(a)), but the present invention is not limited to this embodiment. As another embodiment of the non-discharge detection process during recording, for example, the embodiment shown in FIG. 11 can be mentioned. The processing in the S700 range in FIG. 11 is the same as that in the first embodiment (FIG. 7(a)). As shown in FIG. 11, in S1101 or S1102, the CPU 201 determines whether the image recording process executed in S701 has ended. After the image recording process has ended, the process following the print head recovery process may be executed (S703 YES → S1101 YES → S705, etc.).

[0080] Furthermore, the threshold used in S703 and the threshold used in S707 may be the same or different, and the threshold used in S903 and the threshold used in S906 may be the same or different.

[0081] The present disclosure can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program. It can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0082] [Technical Features of the Present Disclosure] The present disclosure includes the following configurations.

[0083] (Configuration 1) An inkjet recording device comprising: a recording head having a plurality of nozzle arrays, the plurality of nozzle arrays being arranged at different positions in a first direction, and each of the plurality of nozzle arrays being configured by a plurality of nozzles that eject ink arranged in a second direction that intersects the first direction; recovery means for enabling non-ejecting nozzles included in the plurality of nozzles to eject ink and recovering the ejection performance of the recording head; second recording area non-ejection determination means for determining whether each nozzle included in the plurality of nozzles is non-ejecting after a recovery process has been performed by the recovery means, the second recording area non-ejection determination means determining whether each nozzle is in a second recording area that is wider than a first recording medium on which an image recording process is performed; and notification means for notifying of an abnormality in the recording head if, after the second recording area non-ejection determination process has been performed by the second recording area non-ejection determination means, the number of non-ejecting nozzles present in the first recording area of ​​the width of the first recording medium is greater than a predetermined threshold. (Configuration 2) The inkjet recording device described in Configuration 1 further comprises a first recording area non-discharge determination means for determining whether or not each nozzle included in the plurality of nozzles is non-dischargeable, wherein each nozzle is present in the first recording area of ​​the width of the first recording medium, and after a first recording area non-discharge determination process is executed by the first recording area non-discharge determination means and a recovery process is executed by the recovery means, the second recording area non-discharge determination means executes the second recording area non-discharge determination process. (Configuration 3) The inkjet recording apparatus according to configuration 1 or 2, further comprising a transport means for transporting recording media, including the first recording medium, in the first direction. (Configuration 4) A first determination means for determining whether the number of non-discharge nozzles present in the first recording area of ​​the width of the first recording medium is equal to or greater than a predetermined threshold value after the first recording area non-discharge determination process is executed by the first recording area non-discharge determination means; an interruption means for interrupting the image recording process if the determination result of the first determination means is true; an execution means for executing the recovery process by the recovery means after the image recording process is interrupted by the interruption means; and a second determination means for determining whether the number of non-discharge nozzles present in the first recording area is equal to or greater than a predetermined threshold value after the second recording area non-discharge determination process is executed by the second recording area non-discharge determination means. 4. The inkjet recording apparatus according to any one of configurations 1 to 3, further comprising: (Configuration 5) The inkjet recording apparatus according to any one of configurations 1 to 4, wherein when the determination result of the second determination means is true, the notification means notifies of an abnormality in the recording head. (Configuration 6) The inkjet recording apparatus according to any one of configurations 1 to 5, further comprising a restart means for restarting the image recording process interrupted by the interruption means when the judgment result of the second judgment means is false. (Configuration 7) An inkjet recording device according to any one of configurations 1 to 6, further comprising a reading means for reading the first test pattern recorded in the first recording area non-discharge judgment process or the second test pattern recorded in the second recording area non-discharge judgment process, and the first recording area non-discharge judgment means and the second recording area non-discharge judgment means each derive non-discharge information for identifying non-discharge nozzles based on the reading results read by the reading means. (Configuration 8) An inkjet recording device according to any one of configurations 1 to 7, characterized in that the first recording area non-discharge determination process by the first recording area non-discharge determination means is performed while an image recording process is being performed on the first recording medium. (Configuration 9) An inkjet recording device according to any one of configurations 1 to 8, further comprising a third judgment means for judging whether the number of non-discharge nozzles present in the third recording area, derived based on the width of the image to be recorded in the image recording process, is equal to or greater than a predetermined threshold value after the second recording area non-discharge judgment process, which is executed before the image recording process, is executed, and if the judgment result of the third judgment means is true, the notification means notifies of an abnormality in the recording head. (Configuration 10) An inkjet recording device according to any one of configurations 1 to 9, characterized in that the recording head has a plurality of recording heads, and the plurality of recording heads are each arranged so as to have different positions in the first direction. (Configuration 11) An inkjet recording apparatus according to any one of configurations 1 to 10, characterized in that the recovery process by the recovery means is a suction process in which ink is sucked by capping the nozzles and applying negative pressure, a wiping process in which the nozzle surface is wiped with a wiper, a preliminary ejection, or a combination of two or more of the suction process, the wiping process, and the preliminary ejection. (Configuration 12) An inkjet recording apparatus according to any one of configurations 1 to 11, characterized in that the recording head has an electrothermal conversion element that generates ejection energy for ejecting ink from the nozzle, and the first recording area ejection failure determination means or the second recording area ejection failure determination means has a temperature detection element that detects the temperature of the electrothermal conversion element. (Configuration 13) An inkjet recording device according to any one of configurations 1 to 12, characterized in that the first recording area non-discharge determination means or the second recording area non-discharge determination means determines the discharge state of each nozzle based on the temperature change of the electrothermal conversion element detected by the temperature detection element when ink is discharged from the nozzle. (Control method) A control method for an inkjet recording device having a recording head having a plurality of nozzle arrays, the plurality of nozzle arrays being arranged at different positions in a first direction and each of the plurality of nozzle arrays being configured by a plurality of nozzles that eject ink arranged in a second direction that intersects the first direction, and a recovery means that makes non-ejecting nozzles included in the plurality of nozzles capable of ejecting ink and recovers the ejection performance of the recording head, the control method comprising: a second recording area non-ejection determination step that determines whether or not each nozzle included in the plurality of nozzles is non-ejecting after a recovery process is performed by the recovery means, the second recording area non-ejection determination step determining whether or not each nozzle included in the plurality of nozzles is non-ejecting, the second recording area non-ejection determination step being wider than a first recording medium on which an image recording process is performed, and a notification step that notifies of an abnormality in the recording head if, after the second recording area non-ejection determination step is performed, the number of non-ejecting nozzles present in the first recording area of ​​the width of the first recording medium determined in the second recording area non-ejection determination step is greater than a predetermined threshold. (Program) A control method for an inkjet recording device having a recording head having a plurality of nozzle arrays, the plurality of nozzle arrays being arranged at different positions in a first direction and each of the plurality of nozzle arrays being configured by a plurality of nozzles that eject ink being arranged in a second direction that intersects the first direction, and a recovery means that makes non-ejecting nozzles included in the plurality of nozzles capable of ejecting ink and recovers the ejection performance of the recording head, the control method comprising: a second recording area non-ejection determination step that determines whether or not each nozzle included in the plurality of nozzles is non-ejecting after a recovery process is performed by the recovery means, the second recording area non-ejection determination step determining whether or not each nozzle included in the plurality of nozzles is non-ejecting, wherein each of the nozzles is located in a second recording area that is wider than a first recording medium on which an image recording process is performed; and a notification step that notifies of an abnormality in the recording head if, after the second recording area non-ejection determination step is performed, the number of non-ejecting nozzles present in the first recording area of ​​the width of the first recording medium determined in the second recording area non-ejection determination step is greater than a predetermined threshold. [Explanation of symbols]

[0084] 100 Recording device 105 First recording head 201 CPU 208 Engine control unit

Claims

1. a recording head having a plurality of nozzle rows, the plurality of nozzle rows being arranged at different positions in a first direction, and each of the plurality of nozzle rows being configured such that a plurality of nozzles that eject ink are arranged in a second direction that intersects with the first direction; a recovery unit that enables a non-ejecting nozzle included in the plurality of nozzles to eject ink, thereby recovering the ejection performance of the recording head; a second recording area non-ejection determination means for determining whether or not each nozzle included in the plurality of nozzles is non-ejectable after the recovery process has been performed by the recovery means, wherein each nozzle is present in a second recording area having a width larger than that of the first recording medium on which the image recording process is performed; a notification means for notifying an abnormality in the recording head when the number of non-discharge nozzles present in the first recording area of ​​the width of the first recording medium determined by the second recording area non-discharge determination means is greater than a predetermined threshold value after the second recording area non-discharge determination process is performed by the second recording area non-discharge determination means; having An inkjet recording apparatus characterized by:

2. a first print area non-ejection determining means for determining whether each nozzle included in the plurality of nozzles is non-ejectable, the first print area non-ejection determining means being present in the first print area across the width of the first print medium; the first recording area discharge failure determination means executes the first recording area discharge failure determination process, and the recovery means executes the recovery process, and then the second recording area discharge failure determination means executes the second recording area discharge failure determination process.

2. The inkjet recording apparatus according to claim 1, wherein the inkjet recording apparatus is a recording medium.

3. The recording medium conveying device further includes a conveying unit that conveys recording media, including the first recording medium, in the first direction.

3. The inkjet recording apparatus according to claim 2, wherein the inkjet recording apparatus is a recording medium.

4. a first determination means for determining whether the number of non-ejecting nozzles present in the first recording area across the width of the first recording medium is equal to or greater than a predetermined threshold value after the first recording area non-ejection determination process is executed by the first recording area non-ejection determination means; an interruption means for interrupting the image recording process when the determination result of the first determination means is true; an execution unit that executes the recovery process by the recovery unit after the image recording process is interrupted by the interruption unit; a second determination means for determining whether the number of non-ejecting nozzles present in the first recording area is equal to or greater than a predetermined threshold value after the second recording area non-ejection determination process has been executed by the second recording area non-ejection determination means; further comprising 4. The inkjet recording apparatus according to claim 2, wherein the inkjet recording device is a recording medium.

5. When the determination result of the second determination means is true, the notification means notifies the abnormality of the recording head.

5. The inkjet recording apparatus according to claim 4,

6. The image recording apparatus further includes a restart unit that restarts the image recording process interrupted by the interrupt unit when the determination result of the second determination unit is false.

6. The inkjet recording apparatus according to claim 5,

7. further comprising a reading means for reading the first test pattern recorded in the first print area ejection failure determination process or the second test pattern recorded in the second print area ejection failure determination process, the first recording area ejection failure determination means and the second recording area ejection failure determination means each derive ejection failure information for identifying an ejection failure nozzle based on the reading result obtained by the reading means; 7. The inkjet recording apparatus according to claim 6,

8. the first recording area discharge failure determination process by the first recording area discharge failure determination means is executed while an image recording process is being executed on the first recording medium, 8. The inkjet recording apparatus according to claim 7,

9. a third determination means for determining whether the number of non-ejecting nozzles present in a third recording area, which is derived based on the width of an image recorded in the image recording process, is equal to or greater than a predetermined threshold value after the second recording area non-ejection determination process, which is executed before the image recording process, is executed; When the determination result of the third determination means is true, the notification means notifies the abnormality of the recording head.

9. The inkjet recording apparatus according to claim 8,

10. The recording head includes a plurality of recording heads, the plurality of recording heads are arranged so as to be positioned at different positions in the first direction, 10. The inkjet recording apparatus according to claim 9,

11. the recovery process by the recovery means is a suction process in which ink is sucked by capping the nozzles and applying negative pressure, a wiping process in which the nozzle surface is wiped with a wiper, preliminary ejection, or a combination of two or more of the suction process, the wiping process, and the preliminary ejection.

11. The inkjet recording apparatus according to claim 10.

12. the print head has electrothermal conversion elements that generate ejection energy for ejecting ink from the nozzles, the first recording area discharge failure determination means or the second recording area discharge failure determination means has a temperature detection element that detects the temperature of the electrothermal conversion element; 12. The inkjet recording apparatus according to claim 11.

13. the first print area non-discharge determining means or the second print area non-discharge determining means determines the discharge state of each nozzle based on a temperature change of the electrothermal converting element detected by the temperature detecting element when ink is discharged from the nozzle.

13. The inkjet recording apparatus according to claim 12.

14. a recording head having a plurality of nozzle rows, the plurality of nozzle rows being arranged at different positions in a first direction, and each of the plurality of nozzle rows being configured such that a plurality of nozzles that eject ink are arranged in a second direction that intersects with the first direction; a recovery unit that enables a non-ejecting nozzle included in the plurality of nozzles to eject ink, thereby recovering the ejection performance of the recording head; A control method for an inkjet recording apparatus having a second recording area non-ejection determination step for determining whether or not each nozzle included in the plurality of nozzles is non-ejectable after the recovery process has been performed by the recovery means, wherein each nozzle is present in a second recording area having a width larger than that of a first recording medium on which an image recording process is performed; a notification step of notifying an abnormality in the print head when the number of non-discharge nozzles present in the first print area of ​​the width of the first print medium determined in the second print area non-discharge determination step is greater than a predetermined threshold value after the second print area non-discharge determination step has been executed; having A control method comprising:

15. A program for causing a computer to execute the method according to claim 14.

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