RECORDING DEVICE

A recording device includes a head including a plurality of nozzles that are arranged at predetermined intervals in a first direction, the plurality of nozzles being configured to eject liquid, and a controller. The controller is configured to, in a case where the number of the abnormal nozzles among the plurality of nozzles is equal to or greater than the predetermined number and the number of the abnormal nozzles, among a part of the plurality of nozzles in which an interval in the first direction is a preset interval longer than the predetermined interval, is less than the predetermined number, cause the head to eject liquid from the part of nozzles to record an image with a resolution in which a resolution in the first direction is lower than a resolution corresponding to the predetermined interval.

REFERENCE TO RELATED APPLICATIONS

This application claims priority from Japanese Patent Application No. 2022-087381 filed on May 30, 2022. The entire content of the priority application is incorporated herein by reference.

BACKGROUND ART

As a recording device configured to eject liquid from nozzles to perform recording, a printer configured to eject ink from nozzles to perform recording is disclosed in a related art. The printer of the related art includes two heads each having a plurality of nozzles arranged in a direction perpendicular to a sheet conveying direction. In addition, between the two heads, positions, in the sheet conveying direction, of the nozzles are shifted by a length of half an interval between the nozzles in each head. As a result, in the printer of the related art, it is possible to record an image in which a resolution in the direction orthogonal to the sheet conveying direction is a resolution corresponding to the length of half the interval between the nozzles of each head.

DESCRIPTION

Here, in the printer of the related art, any one of the plurality of nozzles of the two heads may be clogged due to contamination of foreign matter, increase in viscosity of ink, or the like, which may cause an abnormal nozzle that cannot eject ink. In a case where an image is recorded in this state, a dot corresponding to the abnormal nozzle is not formed, and a white streak, which is a portion exposed due to a dot corresponding to the abnormal nozzle of a recording sheet is not formed, is generated in the recorded image, which leads to a decrease in image quality.

In such a case, it is considered that by increasing an amount of ink ejected from the nozzles corresponding to a dot adjacent to the abnormal nozzle to increase a size of the dot, a portion, which becomes the white streak, of the recording sheet is filled with the dot whose size is increased, and the deterioration of the image quality can be reduced. However, in this case, since only the amount of ink ejected from the nozzles adjacent to the abnormal nozzle is increased, control becomes complicated. In addition, in the image recorded in this manner, the image quality of the portion where the size of the dot is increased is partially lowered, and the deterioration of the image quality is easily noticeable.

An object of the present disclosure is to provide a recording device capable of making deterioration in image quality less noticeable with simple control in a case where there are a predetermined number or more of abnormal nozzles.

In a recording device according to the present disclosure, a head includes a plurality of nozzles that are arranged at predetermined intervals in a first direction, the plurality of nozzles being configured to eject liquid. A controller is configured to, in a case where the abnormal nozzle information indicates that the number of the abnormal nozzles among the plurality of nozzles is less than the predetermined number, perform a first recording processing of causing the head to eject liquid from the plurality of nozzles while causing the relative movement unit to move the head, with respect to the recording medium, in the second direction to record an image on the recording medium with a resolution in which a resolution in the first direction corresponds to the predetermined interval. The controller is configured to, in a case where the abnormal nozzle information indicates that the number of the abnormal nozzles among the plurality of nozzles is equal to or greater than the predetermined number and indicates that the number of the abnormal nozzles, among a part of the plurality of nozzles in which an interval in the first direction is a preset interval longer than the predetermined interval, is less than the predetermined number, perform a second recording processing of causing the head to eject liquid from the part of nozzles while causing the relative movement unit to move the head, with respect to the recording medium, in the second direction to record an image on the recording medium with a resolution in which a resolution in the first direction is lower than a resolution corresponding to the predetermined interval.

In a recording device according to the present disclosure, a head includes a plurality of first nozzles that are arranged in a first direction, the plurality of first nozzles being configured to eject liquid supplied from a first flow path connected to a liquid storage portion configured to store the liquid, and a plurality of second nozzles that are arranged in the first direction, the plurality of second nozzles being configured to eject liquid supplied from a second flow path connected to the liquid storage portion, the second flow path being different from the first flow path. A controller is configured to, in a case where the abnormal nozzle information indicates that the number of the abnormal nozzles among the plurality of first nozzles is less than the first predetermined number and the number of the abnormal nozzles among the plurality of second nozzles is less than the second predetermined number, perform a first recording processing of causing the head to eject liquid from the plurality of first nozzles and to eject liquid from the plurality of second nozzles to perform recording on the recording medium, while causing the relative movement unit to relatively move the head, with respect to the recording medium, in the second direction. The controller is configured to, in a case where the abnormal nozzle information indicates that the number of the abnormal nozzles among the plurality of first nozzles is equal to or greater than the first predetermined number and the number of the abnormal nozzles among the plurality of second nozzles is less than the second predetermined number, perform a second recording processing of causing the head not to eject liquid from the plurality of first nozzles and to eject liquid from the plurality of second nozzles to perform recording on the recording medium, while causing the relative movement unit to relatively move the head, with respect to the recording medium, in the second direction.

FIRST EMBODIMENT

Hereinafter, a preferred first embodiment of the present disclosure will be described.

<Overall Configuration of Printer>

As illustrated inFIG.1, a printer1(“recording device” of the present disclosure) according to the first embodiment includes a carriage2(“relative movement unit” of the present disclosure), a sub-tank3, an ink jet head4(“head” of the present disclosure), a platen5, conveying rollers6and7, and a maintenance unit8.

The carriage2is supported by two guide rails11and12extending in a scanning direction (“second direction” of the present disclosure). In the following description, a right side and a left side in the scanning direction are defined as illustrated inFIG.1. The carriage2is connected to a carriage motor86(seeFIG.4) via a belt (not illustrated) or the like. In a case where the carriage motor86is driven, the carriage2moves in the scanning direction along the guide rails11and12.

The sub-tank3is mounted on the carriage2. Here, the printer1includes a cartridge holder13. Four ink cartridges14are detachably mounted in the cartridge holder13. The four ink cartridges14mounted in the cartridge holder13are arranged in the scanning direction, and store black ink, yellow ink, cyan ink, and magenta ink (“liquid” of the present disclosure) in order from the one positioned on the right side in the scanning direction.

The ink jet head4is mounted on the carriage2and connected to a lower end portion of the sub-tank3. In addition, the ink jet head4is configured to eject ink from a plurality of nozzles10formed on a nozzle surface4aas a lower surface of the ink jet head4. More specifically, the plurality of nozzles10are arranged at an interval La (“predetermined interval” of the present disclosure) in a conveying direction (“first direction” of the present disclosure) orthogonal to the scanning direction to form nozzle rows9, and four nozzle rows9are arranged, in the scanning direction, on the nozzle surface4a. Positions of the nozzles10in the conveying direction are the same among the four nozzle rows9. The plurality of nozzles10are supplied with black ink, yellow ink, cyan ink, and magenta ink from the sub-tank3in this order from nozzles forming a nozzle row9on the right side. As a result, the black ink, yellow ink, cyan ink, and magenta ink are ejected from the plurality of nozzles10in this order from the nozzles configuring the nozzle row9on the right side in the scanning direction.

In addition, the ink jet head4includes a plurality of individual driving elements20(seeFIG.4) for the plurality of nozzles10. The driving element20is configured to apply ejection energy to ink in a corresponding nozzle10. The driving element20is, for example, a piezoelectric actuator configured to apply pressure to ink in a pressure chamber (not illustrated) communicating with the nozzle10. The plurality of driving elements20are connected to a driver IC89(seeFIG.4). The driver IC89is configured to transmit driving signals to the plurality of driving elements20to drive the plurality of driving elements20.

The platen5is disposed below the ink jet head4and faces the plurality of nozzles10. The platen5extends over an entire length of a recording sheet Pin the scanning direction, and configured to support the recording sheet P from below. The conveying roller6is disposed upstream of the ink jet head4and the platen5in the conveying direction. The conveying roller7is disposed downstream of the ink jet head4and the platen5in the conveying direction. The conveying rollers6and7are connected to a conveying motor87(seeFIG.4) via gears (not illustrated). In a case where the conveying motor87is driven, the conveying rollers6and7rotate to convey the recording sheet P in the conveying direction.

The maintenance unit8includes a cap71, a suction pump72, and a waste liquid tank73. The cap71is disposed on the right side in the scanning direction with respect to the platen5. In a case where the carriage2is positioned at a maintenance position that is on the right side in the scanning direction with respect to the platen5, the plurality of nozzles10face the cap71.

In addition, the cap71is connected to a cap elevating mechanism88(seeFIG.4). In a case where the cap elevating mechanism88is driven, the cap71is lifted and lowered. In a case where the cap71is lifted by the cap elevating mechanism88in a state where the plurality of nozzles10and the cap71face each other by positioning the carriage2at the above-mentioned maintenance position, an upper end portion of the cap71comes into close contact with the nozzle surface4a. As a result, a capped state is established in which the plurality of nozzles10of the ink jet head4are covered with the cap71. In a state where the cap71is lowered, the plurality of nozzles10are not covered with the cap71. The cap71is not limited to those covering the plurality of nozzles10by being in close contact with the nozzle surface4a. For example, the cap71may be those covering the plurality of nozzles10by being in close contact with a frame (not illustrated) or the like disposed around the nozzle surface4aof the ink jet head4.

The suction pump72is a tube pump or the like, and is connected to the cap71and the waste liquid tank73. In the maintenance unit8, in a case where the suction pump72is driven after the above-mentioned capped state is established, suction purge in which ink in the ink jet head4is discharged from the plurality of nozzles10can be performed. The ink discharged by the suction purge is stored in the waste liquid tank73.

Here, for convenience, the cap71collectively covers all the nozzles10, and the ink in the ink jet head4is discharged from all the nozzles10in the suction purge, but the present invention is not limited thereto. For example, the cap71may separately include a portion configured to cover the plurality of nozzles10configuring the nozzle row9on the rightmost side for ejecting black ink, and a portion configured to cover the plurality of nozzles10configuring three nozzle rows9on the left side for ejecting color ink. For example, in the suction purge, any of the black ink and the color ink in the ink jet head4may be selectively discharged. Alternatively, for example, the cap71may be individually provided for respective nozzle rows9, and the ink may be discharged from the nozzles10individually for the respective nozzle rows9in the suction purge.

As illustrated inFIG.2, the electrodes76each having a rectangular planar shape are disposed in the cap71. The electrode76is connected to the high-voltage power supply circuit77via a resistor79. The high-voltage power supply circuit77is configured to apply a predetermined voltage (for example, about 600 V) to the electrode76in a case where the high-voltage power supply circuit77performs the test drive described later. On the other hand, the ink jet head4is maintained at ground potential. As a result, a predetermined potential difference is generated between the ink jet head4and the electrode76. The signal processing circuit78is connected to the electrode76. The signal processing circuit78includes a differentiation circuit and the like, and is configured to output a signal corresponding to a voltage of the electrode76. However, the signal output from the signal processing circuit78may be a current signal.

After the above-mentioned capped state is established, in a state where a voltage is applied to the electrode76by the high-voltage power supply circuit77and the test drive described later is not performed, a voltage of the signal output from the signal processing circuit78is set to a voltage V0illustrated inFIGS.3A and3B.

In the present embodiment, after the above-mentioned capped state is established, in a state where a voltage is applied to the electrode76by the high-voltage power supply circuit77, the ink jet head4is configured to perform the test drive for ejecting ink from each of the plurality of nozzles10toward the electrode76.

In a case where the ink is ejected from the nozzles10by the test drive, the ink ejected from the nozzles10is charged. As a result, the potential of the electrode76changes until the charged ink approaches the electrode76and the ink lands on the electrode76. Then, after the charged ink lands on the electrode76, the potential of the electrode76returns to the potential before ink ejection while being attenuated.

In this case, as illustrated inFIG.3A, a voltage of the signal output from the signal processing circuit78is increased from the voltage V0to a voltage V1that is higher than the voltage V0, is reduced to a voltage V2that is lower than the voltage V0, and thereafter, is repeatedly increased and reduced to return to the voltage V0while being attenuated. As a result, the signal output from the signal processing circuit78has a maximum value of the voltage V1and a minimum value of the voltage V2.

On the other hand, in a case where the ink is not ejected from the nozzles10by the test drive, the signal output from the signal processing circuit78hardly changes from the voltage V0as illustrated inFIG.3B.

As described above, in the present embodiment, the signal output from the signal processing circuit78differs depending on whether the ink is ejected from the nozzles10by the test drive. By utilizing this, in the printer1, it is possible to determine whether a nozzle10is an abnormal nozzle having an abnormality in the ink ejection, as will be described later. Here, in the present embodiment, a predetermined voltage is applied to the electrode76, the ink jet head4is maintained at the ground potential, and the signal processing circuit78is configured to output a signal corresponding to the voltage of the electrode76, but the present invention is not limited thereto. By maintaining the electrode76at the ground potential and applying a predetermined voltage to the ink jet head4, a potential difference may be generated between the electrode76and the ink jet head4, and the signal processing circuit78may be connected to the ink jet head4and configured to output a signal corresponding to the voltage of the ink jet head4.

<Electrical Configuration of Printer>

Next, an electrical configuration of the printer1will be described. As illustrated inFIG.4, the printer1includes a controller80. The controller80includes a central processing unit (CPU)81, a read only memory (ROM)82, a random access memory (RAM)83, a flash memory84(“storage unit” of the present disclosure), and an application specific integrated circuit (ASIC)85. The controller80is configured to control operations of the carriage motor86, the driver IC89, the conveying motor87, the cap elevating mechanism88, the suction pump72, the high-voltage power supply circuit77, and the like. In the first embodiment, the controller80is configured to control the driver IC89to control the ink jet head4. In addition, the controller80is configured to receive a signal from the signal processing circuit78or the like. As described above, the ink jet head4has a plurality of driving elements20, but only one driving element20is illustrated inFIG.4for convenience.

In addition to the configuration described above, the printer1includes a display unit69and an operation unit68. The display unit69is, for example, a liquid crystal display provided on a housing of the printer1. The controller80is configured to control the display unit69to display, on the display unit69, information necessary for an operation of the printer1. The operation unit68includes buttons provided on the housing of the printer1, a touch panel provided on the display unit69, and the like. The operation unit68is configured to receive a signal based on an operation of a user and is configured to transmit the received signal to the controller80.

The controller80may be a controller in which only the CPU81performs various processing, a controller in which only the ASIC85performs various processing, or a controller in which the CPU81and the ASIC85perform various processing in cooperation with each other. In addition, the controller80may be a controller in which one CPU81performs processing independently, or a controller in which a plurality of CPUs81perform processing in a shared manner. Further, the controller80may be a controller in which one ASIC85performs processing independently, or a controller in which a plurality of ASICs85perform processing in a shared manner.

<Determination of Whether Nozzle is Abnormal Nozzle>

Next, processing for determining whether each of the plurality of nozzles10of the ink jet head4is an abnormal nozzle in the printer1will be described. In the printer1, the controller80is configured to control the carriage motor86, the cap elevating mechanism88, and the like to establish the capped state, and then the controller80is configured to cause the ink jet head4to perform the test drive for each of the plurality of nozzles10in a state where a voltage is applied to the electrode76by the high-voltage power supply circuit77. Then, whether the nozzle10is an abnormal nozzle is determined based on a signal output from the signal processing circuit78in this case. Thereafter, information on whether each nozzle10is an abnormal nozzle is stored, in the flash memory84, as abnormal nozzle information.

The above-mentioned processing of determining whether each nozzle10is an abnormal nozzle and of storing a result of the determination in the flash memory84is performed at an appropriate timing. For example, the above-mentioned processing may be performed at a predetermined time. Alternatively, the above-mentioned processing may be performed immediately before a flow shown inFIG.6Ato be described later is started, after a recording instruction signal for instructing recording on the recording sheet P is received. Alternatively, after the previous processing, the above-mentioned processing may be performed in a case where recording is performed on a predetermined number of sheets of recording sheet P. Alternatively, the above-mentioned processing may be performed in a case where a predetermined error occurs in the printer1and then the error is resolved.

Next, processing performed by the controller80in a case where the recording on the recording sheet P is performed in the printer1will be described.

In the printer1, the controller80is configured to control the carriage motor86to move the carriage2in the scanning direction (to relatively move the ink jet head4in the scanning direction with respect to the recording sheet P). Then, the controller80is configured to repeatedly perform, based on recording data instructing ejection of ink from each nozzle10, a recording pass in which the controller80cause the ink jet head4to eject the ink from the plurality of nozzles10, and a conveying operation in which the controller80controls the conveying motor87to cause the conveying rollers6and7to convey the recording sheet P, in the conveying direction, by a length of the nozzle row9. Thus, the recording on the recording sheet P can be performed. Here, in the printer1, in a case where the controller80receives the recording instruction signal instructing the recording on the recording sheet P, the recording on the recording sheet P is performed. In addition, in a case where the controller80receives the recording instruction signal instructing the recording on the recording sheet P, the controller80acquires the recording data by receiving the recording data. Alternatively, in a case where the controller80receives the recording instruction signal, the controller80may generate recording data by receiving image data of an image to be recorded and generating the recording data from the image data.

Further, in the printer1, in a case where the controller80receives the recording instruction signal, the recording on the recording sheet P is performed by performing processing with reference to a flow shown inFIG.5. The flow shown inFIG.5will be described in more detail. First, the controller80determines whether the number N1of abnormal nozzles among the plurality of nozzles10of the ink jet head4is equal to or greater than a predetermined number Na, based on the abnormal nozzle information stored in the flash memory84(step S101). Here, the predetermined number Na may be one or two or more. In a case where the predetermined number Na is one, it is determined, in step S101, whether there is an abnormal nozzle among the plurality of nozzles10of the ink jet head4.

In a case where the number N1of abnormal nozzles is less than the predetermined number Na (NO in step S101), the controller80performs first recording processing (step S102). In the first recording processing, the controller80repeatedly performs the recording pass and the conveying operation as described above to perform the recording on the recording sheet P. In addition, in a case where the recording pass is performed in the first recording processing, the controller80sets all of the plurality of nozzles10of the ink jet head4to be usable nozzles10, and drives the ink jet head4to eject ink from the plurality of nozzles10. As a result, in the first recording processing, as illustrated inFIG.6A, an interval in the conveying direction of dots D formed in one recording pass is the same as the interval La of the nozzles10in the nozzle rows9. That is, in the first recording processing, in each recording pass, the image is recorded on the recording sheet P with a resolution (for example, 1,200 dpi) in which the resolution in the conveying direction corresponds to the interval La. In addition, in the first embodiment, the recording sheet P is conveyed, by the length of the nozzle row9in the conveying direction, by the conveying operation. As a result, in the first embodiment, the resolution in the conveying direction of the image recorded in the first recording processing is also the resolution (for example, 1,200 dpi) corresponding to the interval La.

When the number N1of abnormal nozzles is equal to or greater than the predetermined number Na (YES in step S101), the controller80determines whether the number N2of abnormal nozzles, among the nozzles10set to be usable can be less than the predetermined number Na by performing recording with a low resolution set in advance (step S103).

More specifically, in the first embodiment, a low resolution lower than the resolution in which the resolution, in the conveying direction, corresponds to the interval La is set in advance, and information of the low resolution is stored in the flash memory84, as information of low resolution recording.

In the first embodiment, as the information of the low resolution recording, for example, information indicating that the recording is performed by setting only every other nozzle10, among the plurality of nozzles10forming the nozzle rows9as illustrated inFIG.6B, to be usable is stored in the flash memory84. In this case, among a plurality of dots D formed in a case where the recording is performed by the first recording processing, dots D other than every other dot D in the conveying direction are thinned out. As a result, the interval, in the conveying direction, of the dots D formed in one recording pass is twice the interval La (2×La). That is, in a case where the recording is performed as illustrated inFIG.6B, in each recording pass, an image is recorded, on the recording sheet P, with a resolution (for example, 600 dpi) in which the resolution in the conveying direction is half a resolution in the case where the recording is performed by the first recording processing.

In addition, in the first embodiment, as the information of the low resolution recording, for example, information indicating that the recording is performed by setting only every three nozzles10, among the plurality of nozzles10forming the nozzle rows9as illustrated inFIG.6C, to be usable is stored in the flash memory84. In this case, among the plurality of dots D formed in a case where the recording is performed by the first recording processing, dots D other than every three dots D in the conveying direction are thinned out. As a result, the interval, in the conveying direction, of the dots D formed in one recording pass is four times the interval La (4×La). That is, in a case where the recording is performed as illustrated inFIG.6C, in each recording pass, an image is recorded, on the recording sheet P, with a resolution (for example, 300 dpi) in which the resolution in the conveying direction is one quarter of a resolution in the case where the recording is performed by the first recording processing.

The information of the low resolution recording is not limited to the information indicating the recording with the resolutions illustrated inFIGS.6B and6C, and may be information indicating recording with a different resolution. In addition, the stored information of the low resolution recording is not limited to two types, and may be one type or three or more types.

In step S103, it is determined whether the number N2of abnormal nozzles can be less than the predetermined number Na by performing the recording with the low resolution indicated by the information of the low resolution recording. Here, in a case where whether the number N2of abnormal nozzles can be less than the predetermined number Na is determined by performing the recording with the resolution illustrated inFIG.6B, it is determined not only whether the number N2of abnormal nozzles can be less than the predetermined number Na by setting every other nozzle10illustrated inFIG.6Bto be usable, but also whether the number N2of abnormal nozzles can be less than the predetermined number Na by setting any every other nozzle10other than those described above to be usable. In addition, in a case where whether the number N2of abnormal nozzles can be less than the predetermined number Na is determined by performing the recording with the resolution illustrated inFIG.6C, it is determined not only whether the number N2of abnormal nozzles can be less than the predetermined number Na by setting every three nozzles10illustrated inFIG.6Cto be usable, but also whether the number N2of abnormal nozzles can be less than the predetermined number Na by setting any every three nozzles10other than those described above to be usable.

In a case where the number N2of abnormal nozzles cannot be less than the predetermined number Na even in a case where the recording is performed with the low resolution as described above (NO in step S103), the controller80performs a purge processing (step S104) and then performs the first recording processing (S102). In the purge processing of step S104, the controller80is configured to control the suction pump72and the like to perform the above-described suction purge.

In a case where the number N2of abnormal nozzles can be less than the predetermined number Na by performing the recording with a low resolution as described above (YES in step S103), the controller80is configured to perform a second recording processing (step S105). In the second recording processing, the controller80is configured to repeatedly perform the recording pass and the conveying operation, as described above, to perform the recording on the recording sheet P. In addition, in a case where the recording pass is performed in the second recording processing, the controller80is configured to set only a part of the plurality of nozzles10of the ink jet head4as usable nozzles10, and configured to drive the ink jet head4to eject ink from the part of the nozzles10, thereby performing the recording such that the resolution in the conveying direction becomes the above-mentioned low resolution. Here, the part of the nozzles10set to be usable refers to, for example, every other nozzle10in the nozzle rows9in a case where the recording is performed with the resolution illustrated inFIG.6B, and refers to every three nozzles10in the nozzle rows9in a case where the recording is performed with the resolution illustrated inFIG.6C. In this case, in a case where the number N2of abnormal nozzles can be less than the predetermined number Na even when a plurality of types of low resolutions are set in advance and the recording is performed with any of two or more types of low resolutions, the recording is performed with the highest resolution among the two or more types of low resolutions. In addition, in a case where there are a plurality of ways to select the part of the nozzles10set to be usable such that the number N2of abnormal nozzles is less than the predetermined number Na with the same low resolution, the part of the nozzles10set to be usable is selected such that the number N2of abnormal nozzles is the smallest.

In the first embodiment, in the second recording processing, the recording sheet P is also conveyed, by the length of the nozzle row9, in the conveying direction by the conveying operation. As a result, in a case where the image is recorded on the recording sheet P, in each recording pass, with the resolution illustrated inFIG.6B, the resolution, in the conveying direction, of the recorded image is half the resolution in the case where the recording is performed by the first recording processing. In addition, in a case where the image is recorded on the recording sheet P, in each recording pass, with the resolution illustrated inFIG.6C, the resolution, in the conveying direction, of the recorded image is one quarter of the resolution in the case where the recording is performed by the first recording processing.

As illustrated inFIGS.6A to6C, in the second recording processing, the controller80is configured to increase, compared to the first recording processing, the amount of ink ejected from the nozzles10in the recording pass to increase a size of the dots D. In addition, in a case where a plurality of types of low resolutions are set in advance, the controller80is configured to increase the amount of ink ejected from the nozzles10in the recording pass as the recording is performed with a lower resolution to increase the size of the dots D.

In the first embodiment, in a case where the number N1of abnormal nozzles among the plurality of nozzles10of the ink jet head4is less than the predetermined number Na, it is possible to record an image with a high image quality having a resolution in which the resolution, in the conveying direction, corresponds to the interval La of the nozzles10in the nozzle rows9.

On the other hand, in a case where the number N1of abnormal nozzles among the plurality of nozzles10of the ink jet head4is equal to or greater than the predetermined number Na, and the number N2of abnormal nozzles is less than the predetermined number Na by performing the recording with a low resolution set in advance, it is possible to record an image of which the resolution in the conveying direction is lower than the resolution corresponding to the interval La of the nozzles10. In this case, in a case where recording is switched from the recording with the resolution corresponding to the interval La of the nozzles10to the recording with the low resolution, it is only necessary to change the control such that the ink is ejected from only a part of the plurality of nozzles10of the ink jet head4, and thus the control by the controller80can be simplified. In addition, in this case, the image quality of the recorded image is uniformly lowered as the resolution in the conveying direction is lowered. Therefore, as compared with a case where the image quality of the recorded image is partially lowered by performing the recording without lowering the resolution in the conveying direction and not ejecting the ink from the abnormal nozzles, the degradation in image quality can be made less noticeable.

In the first embodiment, in a case where the recording is performed with a lower resolution, an area of a region where dots are not formed in the recorded image is reduced by increasing the amount of ink ejected from the nozzles10to increase the size of the dots.

In the present disclosure, the expression of “causing the head to eject a liquid from the plurality of nozzles while causing the relative movement unit to move the head with respect to the recording medium in the second direction, thereby recording an image, on the recording medium, with a resolution in which a resolution in the first direction corresponds to the predetermined interval” means that, for example, the resolution, in the first direction, in one recording pass is the resolution corresponding to the interval (predetermined interval) in the first direction of the plurality of nozzles in the head. In other words, the expression means that the interval, in the first direction, of the plurality of dots formed by a first recording pass is the interval (predetermined interval), in the first direction, of the plurality of nozzles in the head. In this case, the resolution, in the first direction, of the image finally recorded may be the resolution corresponding to the predetermined interval or may be another resolution.

In addition, in the present disclosure, the expression of “causing the head to eject a liquid from the part of nozzles while causing the relative movement unit to move the head, with respect to the recording medium, in the second direction, thereby recording an image, on the recording medium, with a resolution in which the resolution in the first direction is lower than the resolution corresponding to the predetermined interval” means that, for example, the resolution in the first direction in one recording pass is the resolution corresponding to the interval (interval longer than the predetermined interval), in the first direction, of a part of the nozzles among the plurality of nozzles of the head usable for recording. In other words, the expression means that the interval, in the first direction, of the plurality of dots formed in one recording pass is the interval (longer than the predetermined interval), in the first direction, of the part of the nozzles. In this case, the resolution, in the first direction, of the image finally recorded may be a resolution lower than the resolution corresponding to the predetermined interval, or may be another resolution such as the resolution corresponding to the predetermined interval.

Second Embodiment

Next, a preferred second embodiment of the present disclosure will be described. As illustrated inFIGS.7and8, a printer100according to the second embodiment is obtained by partially modifying the configuration of the printer1according to the first embodiment. In a configuration of the printer100, components denoted by the same reference numerals as those of the printer1inFIGS.7and8are the same as those of the printer1. The printer100includes a sub-tank103, an ink jet head104, and a cartridge holder113.

The sub-tank103is mounted on the carriage2. Two ink cartridges114(“liquid storage portion” of the present disclosure) arranged in the scanning direction are detachably mounted in the cartridge holder113. Ink of the same color (for example, black ink) is stored in the two ink cartridges114. The sub-tank103is connected to the two ink cartridges114via two tubes115, and the ink is supplied from the two ink cartridges114.

The ink jet head104has two nozzle rows109, arranged in the scanning direction, formed by arranging the plurality of nozzles10at an interval Lb (“predetermined interval” of the present disclosure) in the conveying direction. In addition, positions, in the conveying direction of the nozzle row109, of the nozzles10of the right side and the nozzle row109on the left side are shifted from each other by a length (Lb/2) that is half the interval Lb of the nozzles10in each nozzle row109.

In the second embodiment, ink supplied from the ink cartridge114on the right side to the sub-tank103is supplied from the sub-tank103to the plurality of nozzles10forming the nozzle row109on the right side. In addition, in the second embodiment, ink supplied from the ink cartridge114on the left side to the sub-tank103is supplied from the sub-tank103to the plurality of nozzles10forming the nozzle row109on the left side.

In the second embodiment, of the two ink cartridges114, one ink cartridge114corresponds to a “first liquid storage portion” of the present disclosure, and the other ink cartridge114corresponds to a “second liquid storage portion” of the present disclosure. In addition, the plurality of nozzles10that form one of the two nozzle rows109and are supplied with ink from the ink cartridge114serving as the first liquid storage portion correspond to “first nozzles” of the present disclosure. Further, the plurality of nozzles10that form the other of the two nozzle rows109and are supplied with ink from the ink cartridge114serving as the second liquid storage portion correspond to “second nozzles” of the present disclosure.

In the second embodiment, flow paths and the tubes115in the ink jet head104and the sub-tank103, which connect the first nozzles and the ink cartridge114serving as the first liquid storage portion, correspond to “first flow paths” of the present disclosure. In addition, flow paths and the tubes115in the ink jet head104and the sub-tank103, which connect the second nozzles and the ink cartridge114serving as the second liquid storage portion, correspond to “second flow paths” of the present disclosure.

As illustrated inFIG.8, the ink jet head104includes a plurality of first driving elements120a(“first elements” of the present disclosure) and a plurality of second driving elements120b(“second elements” of the present disclosure). The plurality of first driving elements120aare individually provided in the above-mentioned plurality of first nozzles. The plurality of second driving elements120bare individually provided in the above-mentioned plurality of second nozzles. The respective driving elements120aand120bare similar to the driving elements20according to the first embodiment. As described above, the ink jet head104includes the plurality of first driving elements120aand the plurality of second driving elements120b, but inFIG.8, only one first driving element120aand only one second driving element120bare illustrated for convenience.

The printer100includes a first driver IC130a(“first driving signal output unit” of the present disclosure) and a second driver IC130b(“second driving signal output unit” of the present disclosure). The first driver IC130ais connected to the plurality of first driving elements120a, and is configured to output driving signals to the plurality of first driving elements120ato drive the plurality of first driving elements120aindividually. The second driver IC130bis connected to the plurality of second driving elements120b, and is configured to output driving signals to the plurality of second driving elements120bto drive the plurality of second driving elements120bindividually.

Next, processing performed by the controller80in a case where the recording on the recording sheet P is performed in the printer100according to the second embodiment will be described.

In the printer100, in a case where the controller80receives a recording instruction signal, the processing is performed with reference to a flow shown inFIG.9. The flow shown inFIG.9will be described in more detail. First, the controller80determines whether the number N3of abnormal nozzles in the nozzle row109on the right side is equal to or greater than a predetermined number N3a, based on the abnormal nozzle information stored in the flash memory84(step S201). Here, the predetermined number N3amay be one or two or more. In a case where the predetermined number N3ais one, in step S201, it is determined whether there is an abnormal nozzle among the plurality of nozzles10forming the nozzle row109on the right side.

In a case where the number N3of abnormal nozzles is less than the predetermined number N3a(NO in step S201), the processing directly proceeds to step S203. In a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3a(YES in step S201), the controller80sets the nozzle row109on the right side to non-use (step S202), and the processing proceeds to step S203.

In step S203, the controller80determines whether the number N4of abnormal nozzles in the nozzle row109on the left side is equal to or greater than a predetermined number N4a, based on the abnormal nozzle information stored in the flash memory84. Here, the predetermined number N4amay be one or two or more. In a case where the predetermined number N4ais one, in step S203, it is determined whether there is an abnormal nozzle among the plurality of nozzles10forming the nozzle row109on the left side. In addition, the predetermined number N4amay be the same as the predetermined number N3a, or may be different from the predetermined number N3a.

In a case where the number N4of abnormal nozzles is less than the predetermined number N4a(NO in step S203), the processing directly proceeds to step S205. In a case where the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a(YES in step S203), the controller80sets the nozzle row109on the left side to non-use (step S204), and the processing proceeds to step S205.

In a case where it is assumed that the nozzles10forming the nozzle row109on the right side are the first nozzles and the nozzles10forming the nozzle row109on the left side are the second nozzles, the predetermined number N3acorresponds to a “first predetermined number” of the present disclosure, and the predetermined number N4acorresponds to a “second predetermined number” of the present disclosure. In a case where it is assumed that the nozzles10forming the nozzle row109on the left side are the first nozzles and the nozzles10forming the nozzle row109on the right side are the second nozzles, the predetermined number N4acorresponds to the “first predetermined number” of the present disclosure, and the predetermined number N3acorresponds to the “second predetermined number” of the present disclosure.

In step S205, the controller80determines whether both of the nozzle rows109are set to non-use. In a case where none of the nozzle rows109is set to non-use or only one of the nozzle rows109is set to non-use (NO in step S205), the processing directly proceeds to step S207. In a case where both of the nozzle rows109are set to non-use (YES in step S205), the controller80cancels a setting of non-use of a nozzle row109having a smaller number of abnormal nozzles among the two nozzle rows109(step S206), and the processing proceeds to step S207.

In step S207, the controller80performs a recording processing. In the recording processing, the controller80is configured to repeatedly perform the recording pass and the conveying operation as described above to perform the recording on the recording sheet P. However, in the second embodiment, in the conveying operation, the recording sheet P is conveyed, in the conveying direction, by the same length as the interval, in the conveying direction, between the most upstream nozzle10of the nozzle row109on the right side and the most downstream nozzle10of the nozzle row109on the left side. In addition, in a case where the recording pass is performed in the recording processing, the controller80is configured to drive the ink jet head4to eject ink only from the nozzles10forming the nozzle row109that is not set to non-use. In this case, the ink is ejected from the nozzles10such that landing positions, in the scanning direction, of the ink ejected from the nozzles10on the recording sheet P are the same in the nozzle row109on the left side and the nozzle row109on the right side.

As a result, in a case where the number N3of abnormal nozzles is less than the predetermined number N3aand the number N4of abnormal nozzles is less than the predetermined number N4a, none of the nozzle rows109is set to non-use, and as illustrated inFIG.10A, in the recorded image, dots Da formed by the ink ejected from the nozzles10forming the nozzle row109on the left side and dots db formed by the ink ejected from the nozzles10forming the nozzle row109on the right side are alternately arranged in the conveying direction. In this case, in each recording pass, the image is recorded, on the recording sheet P, with the resolution, in the conveying direction, in which an interval between the dots Da and the dots db adjacent in the conveying direction is (Lb/2). In addition, since the recording sheet P is conveyed, in the conveying direction, by the same length as the interval, in the conveying direction, between the most upstream nozzle10of the nozzle row109on the right side and the most downstream nozzle10of the nozzle row109on the left side by the conveying operation, the resolution, in the conveying direction, of the recorded image is also the resolution in which the interval between the adjacent dots Da and dots db is (Lb/2). The recording processing performed in this case corresponds to the “first recording processing” of the present disclosure.

In a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3aand the number N4of abnormal nozzles is less than the predetermined number N4a, only the nozzle row109on the right side is set to non-use, and as illustrated inFIG.10B, the recorded image is formed by the dots Da obtained by thinning out the dots db from the image illustrated inFIG.10A. In this case, in each recording pass, the image is recorded, on the recording sheet P, with a resolution in the conveying direction (resolution that is half the resolution in the case ofFIG.10A) in which the interval between the dots Da adjacent to each other in the conveying direction is Lb. In addition, since the recording sheet P is conveyed, in the conveying direction, by the same length as the interval in the conveying direction between the most upstream nozzle10of the nozzle row109on the right side and the most downstream nozzle10of the nozzle row109on the left side by the conveying operation, the resolution in the conveying direction of the recorded image in this case is also the resolution in the conveying direction in which the interval between the dots Da in the conveying direction is Lb (resolution that is half the resolution in the case ofFIG.10A).

In a case where the number N3of abnormal nozzles is less than the predetermined number N3aand the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, only the nozzle row109on the left side is set to non-use, and as illustrated inFIG.10C, the image recorded is formed by the dots db obtained by thinning out the dots Da from the image illustrated inFIG.10A. In this case, in each recording pass, the image is recorded, on the recording sheet P, with a resolution in the conveying direction (resolution that is half the resolution in the case ofFIG.10A) in which the interval between the dots db adjacent to each other in the conveying direction is Lb. In addition, since the recording sheet P is conveyed, in the conveying direction, by the same length as the interval in the conveying direction between the most upstream nozzle10of the nozzle row109on the right side and the most downstream nozzle10of the nozzle row109on the left side by the conveying operation, the resolution, in the conveying direction, of the recorded image in this case is also the resolution in the conveying direction in which the interval between the dots db in the conveying direction is Lb (resolution that is half the resolution in the case ofFIG.10A).

In a case where it is assumed that the nozzles10forming the nozzle row109on the right side are the first nozzles of the present disclosure and the nozzles10forming the nozzle row109on the left side are the second nozzles of the present disclosure, the recording processing of step S207when the recording is performed as illustrated inFIG.10Bcorresponds to the “second recording processing” of the present disclosure. On the other hand, in a case where it is assumed that the nozzles10forming the nozzle row109on the left side are the first nozzles of the present disclosure and the nozzles10forming the nozzle row109on the right side are the second nozzles of the present disclosure, the recording processing of step S207when the recording is performed as illustrated inFIG.10Ccorresponds to the “second recording processing” of the present disclosure.

In a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3a, the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, and the number N4of abnormal nozzles is smaller than the number N3of abnormal nozzles, as illustrated inFIG.10B, the recording is performed by ejecting the ink from the plurality of nozzles10forming the nozzle row109on the left side. On the other hand, in a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3a, the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, and the number N3of abnormal nozzles is smaller than the number N4of abnormal nozzles, as illustrated inFIG.10C, the recording is performed by ejecting the ink from the plurality of nozzles10forming the nozzle row109on the right side. That is, the recording is performed by ejecting the ink from the plurality of nozzles10forming the nozzle row109having a smaller number of abnormal nozzles among the two nozzle rows109. In the second embodiment, the recording processing performed in this case corresponds to a “third recording processing” of the present disclosure.

As illustrated inFIGS.10A to10C, in a case where the recording is performed by ejecting the ink only from the nozzles10forming one of the two nozzle rows109, sizes of the dots Da and db are increased by increasing the amount of ink ejected from the nozzles10as compared with a case where the recording is performed by ejecting the ink from the nozzles10forming both the nozzle rows109.

In a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3a, the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, and the number N3of abnormal nozzles is the same as the number N4of abnormal nozzles, the recording may be performed by ejecting the ink only from the nozzles10forming the nozzle row109on the right side as illustrated inFIG.10B, or the recording may be performed by ejecting the ink only from the nozzles10forming the nozzle row109on the left side as illustrated inFIG.10C.

In the second embodiment, between the nozzle row109on the right side and the nozzle row109on the left side, the positions, in the conveying direction, of the nozzles10are shifted by the length (Lb/2) that is half the interval Lb between the nozzles10in each nozzle row109. In a case where the number N3of abnormal nozzles is less than the predetermined number N3aand the number N4of abnormal nozzles is less than the predetermined number N4a, by performing the recording by driving the ink jet head104to eject the ink from the plurality of nozzles10forming both the nozzle rows109, the resolution, in the conveying direction, of the recorded image can be increased.

In the second embodiment, in a case where the number N3of abnormal nozzles is less than the predetermined number N3aand the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, the recording is performed by driving the ink jet head4such that the ink is not ejected from the nozzles10forming the nozzle row109on the left side and the ink is ejected from the nozzles10forming the nozzle row109on the right side. In addition, in a case where the number N3of abnormal nozzles in the nozzle row109on the right side is equal to or greater than the predetermined number N3aand the number N4of abnormal nozzles in the nozzle row109on the left side is less than the predetermined number N4a, the recording is performed by driving the ink jet head4such that the ink is not ejected from the nozzles10forming the nozzle row109on the right side and the ink is ejected from the nozzles10forming the nozzle row109on the left side. As a result, in a case where the number of abnormal nozzles in any of the nozzle rows109is equal to or greater than a predetermined number, the recording can be performed with a lower resolution in the conveying direction with a simple processing. In this case, since the image quality of the recorded image is uniformly lowered as the resolution in the conveying direction is lowered, as compared with the case where the image quality of the recorded image is partially lowered by performing the recording without lowering the resolution in the conveying direction and not ejecting the ink from the abnormal nozzle, the degradation in image quality is less noticeable.

In the second embodiment, in a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3aand the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, the recording is performed by driving an ink jet head204such that the ink is ejected only from the plurality of nozzles10forming the nozzle row109having a smaller number of abnormal nozzles among the two nozzle rows109. As a result, the recording can be performed with a lower resolution in the conveying direction with a simple processing. In addition, in a case where the recording is performed with a lower resolution in the conveying direction, deterioration in image quality due to ink not being ejected from the abnormal nozzle can be avoided as much as possible.

In the second embodiment, the ink is supplied, from different ink cartridges114, to the plurality of nozzles10forming the nozzle row109on the right side and the plurality of nozzles10forming the nozzle row109on the left side. In addition, in the second embodiment, the plurality of first driving elements120acorresponding to the plurality of nozzles10forming one of the nozzle rows109are driven by the first driver IC130a, and the plurality of second driving elements120bcorresponding to the plurality of nozzles10forming the other of the nozzle rows109are driven by the second driver IC130b. In the second embodiment, in the printer100having such a configuration, as described above, the recording as described above can be performed according to the number of abnormal nozzles10in each nozzle row109.

Also, in the second embodiment, in a case where the recording is performed with a lower resolution in the conveying direction, by increasing the amount of ink ejected from the nozzles10to increase the size of the dots, an area of a region where the dots are not formed in the recorded image is reduced.

Third Embodiment

Next, a preferred third embodiment of the present disclosure will be described. As illustrated inFIG.11, a printer200according to the third embodiment is obtained by replacing the ink jet head104in the printer100according to the second embodiment with the ink jet head204. Similar to the ink jet head104, the ink jet head204includes a plurality of nozzles10forming two nozzle rows109, but unlike the ink jet head104, positions, in the conveying direction, of the nozzles10of the two nozzle rows109are the same.

In a case where recording is performed in the printer200according to the third embodiment, the controller80is configured to perform processing with reference to the flow shown inFIG.9, as described in the second embodiment. However, in the third embodiment, for example, in the recording processing of step S207, by setting ejection timings of the ink from the nozzles10in the two nozzle rows109in the recording pass to be the same, a landing position of ink ejected from the nozzles10forming the nozzle row109on the left side on the recording sheet P and a landing position of ink ejected from the nozzles10forming the nozzle row109on the right side on the recording sheet P are adjacent to each other in the scanning direction. In the printer200according to the third embodiment, a recording result of the recording processing is different from that in the second embodiment.

More specifically, in a case where the number N3of abnormal nozzles is less than the predetermined number N3aand the number N4of abnormal nozzles is less than the predetermined number N4a, none of the nozzle rows9is set to non-use, and as illustrated inFIG.12A, dots Dc formed by the ink ejected from the nozzles10forming the nozzle row109on the left side and dots Dd formed by the ink ejected from the nozzles10forming the nozzle row109on the right side are alternately arranged in the scanning direction. The resolution, in the scanning direction, of the recorded image in this case is a resolution in which an interval, between adjacent dots Dc and Dd, in the scanning direction is W. The recording processing performed in this case corresponds to the “first recording processing” of the present disclosure.

In a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3aand the number N4of abnormal nozzles is less than the predetermined number N4a, only the nozzle row9on the right side is set to non-use, and as illustrated inFIG.12B, the recorded image is formed by the dots Dc obtained by thinning out the dots Dd from the image shown inFIG.12A. The resolution, in the scanning direction, of the recorded image in this case is a resolution in which the interval between the dots Dc adjacent to each other in the scanning direction is (2×W) (half the resolution in the case ofFIG.10A).

In a case where the number N3of abnormal nozzles is less than the predetermined number N3aand the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, only the nozzle row9on the left side is set to non-use, and as illustrated inFIG.12C, the recorded image is formed by the dots Dd obtained by thinning out the dots Dc from the image illustrated inFIG.12A. The resolution, in the scanning direction, of the recorded image in this case is a resolution in which the interval between the dots Dd adjacent to each other in the scanning direction is (2×W) (half the resolution in the case ofFIG.10A).

In a case where it is assumed that the nozzles10forming the nozzle row109on the right side are the first nozzles of the present disclosure and the nozzles10forming the nozzle row109on the left side are the second nozzles of the present disclosure, the recording processing of step S207when the recording is performed as illustrated inFIG.12Bcorresponds to the “second recording processing” of the present disclosure. On the other hand, in a case where it is assumed that the nozzles10forming the nozzle row109on the left side are the first nozzles of the present disclosure and the nozzles10forming the nozzle row109on the right side are the second nozzles of the present disclosure, the recording processing of step S207when the recording is performed as illustrated inFIG.12Ccorresponds to the “second recording processing” of the present disclosure.

In a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3a, the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, and the number N4of abnormal nozzles is smaller than the number N3of abnormal nozzles, as illustrated inFIG.12B, the recording is performed by ejecting the ink from the plurality of nozzles10forming the nozzle row109on the left side. On the other hand, in a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3a, the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, and the number N3of abnormal nozzles is smaller than the number N4of abnormal nozzles, as illustrated inFIG.12C, the recording is performed by ejecting the ink from the plurality of nozzles10forming the nozzle row109on the right side. That is, the recording is performed by ejecting the ink from the plurality of nozzles10forming the nozzle row109having a smaller number of abnormal nozzles among the two nozzle rows109. In the third embodiment, the recording processing performed in this case corresponds to the “third recording processing” of the present disclosure.

As illustrated inFIGS.12A to12C, in a case where the recording is performed by ejecting the ink only from the nozzles10forming one of the two nozzle rows109, sizes of the dots Dc and Dd are increased by increasing the amount of ink ejected from the nozzles10, as compared with a case where the recording is performed by ejecting the ink from the nozzles10forming both the nozzle rows109.

In a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3a, the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, and the number N3of abnormal nozzles is the same as the number N4of abnormal nozzles, the recording may be performed by ejecting the ink only from the nozzles10forming the nozzle row109on the right side as illustrated inFIG.12B, or the recording may be performed by ejecting the ink only from the nozzles10forming the nozzle row109on the left side as illustrated inFIG.12C.

In the third embodiment, the positions, in the conveying direction, of the nozzles10are the same in the nozzle row109on the right side and the nozzle row109on the left side. In a case where the number N3of abnormal nozzles is less than the predetermined number N3aand the number N4of abnormal nozzles is less than the predetermined number N4a, by performing the recording by driving the ink jet head204to eject the ink from the plurality of nozzles10forming both the nozzle rows109, the resolution, in the scanning direction, of the recorded image can be increased.

In the second embodiment, in a case where the number N3of abnormal nozzles is less than the predetermined number N3aand the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, the recording is performed by driving the ink jet head204such that the ink is not ejected from the nozzles10forming the nozzle row109on the left side and the ink is ejected from the nozzles10forming the nozzle row109on the right side. In addition, in a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3aand the number N4of abnormal nozzles is less than the predetermined number N4a, the recording is performed by driving the ink jet head204such that the ink is not ejected from the nozzles10forming the nozzle row109on the right side and the ink is ejected from the nozzles10forming the nozzle row109on the left side. As a result, in a case where the number of abnormal nozzles in any of the nozzle rows109is equal to or greater than a predetermined number, the recording can be performed with a lower resolution in the scanning direction with a simple processing. In this case, since the image quality of the recorded image is uniformly lowered as the resolution in the scanning direction is lowered, as compared with the case where the image quality of the recorded image is partially lowered by performing the recording without lowering the resolution in the scanning direction and not ejecting the ink from the abnormal nozzle, the degradation in image quality is less noticeable.

In the third embodiment, in a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3aand the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, the recording is performed by driving the ink jet head204such that the ink is ejected only from the plurality of nozzles10forming the nozzle row109having a smaller number of abnormal nozzles among the two nozzle rows109. As a result, the recording can be performed with a lower resolution in the scanning direction with simple processing. In addition, in a case where the recording is performed with a lower resolution in the scanning direction, deterioration in image quality due to ink not being ejected from the abnormal nozzle can be avoided as much as possible.

Fourth Embodiment

Next, a preferred fourth embodiment of the present disclosure will be described. The fourth embodiment relates to the printer100similar to that of the second embodiment or the printer200similar to that of the third embodiment. In the fourth embodiment, in a case where recording is performed in the printer, the controller80is configured to perform processing with reference to a flow shown inFIG.13. In the flow shown inFIG.13, step S201of the flow inFIG.9is replaced with step S301, and step S203of the flow shown inFIG.9is replaced with step S302.

In step S301, based on the abnormal nozzle information stored in the flash memory84and the recording data, the controller80determines whether the number N5of abnormal nozzles, among the nozzles10used in the case where the recording is performed by ejecting the ink based on the recording data among the plurality of nozzles10forming the nozzle row109on the right side, is equal to or greater than a predetermined number N5a. Here, the predetermined number N5amay be one or two or more. Then, in a case where the number N5of abnormal nozzles is less than the predetermined number N5a(NO in step S301), the processing proceeds to step S203. In a case where the number N5of abnormal nozzles is equal to or greater than the predetermined number N5a(YES in step S301), the processing proceeds to step S203.

In step S302, based on the abnormal nozzle information stored in the flash memory84and the recording data, the controller80determines whether the number N6of abnormal nozzles, among the nozzles10used in the case where the recording is performed by ejecting the ink based on the recording data in the nozzle row109on the left side, is equal to or greater than a predetermined number N6a. Here, the predetermined number N6amay be one or two or more. Then, in a case where the number N6of abnormal nozzles is less than the predetermined number N6a(NO in step S302), the processing proceeds to step S205. In a case where the number N6of abnormal nozzles is equal to or greater than the predetermined number N6a(YES in step S302), the processing proceeds to step S204.

In the fourth embodiment, in a case where it is assumed that the nozzles10forming the nozzle row109on the right side are the first nozzles and the nozzles10forming the nozzle row109on the left side are the second nozzles, the predetermined number N5acorresponds to the “first predetermined number” of the present disclosure, and the predetermined number N6acorresponds to the “second predetermined number” of the present disclosure. In a case where it is assumed that the nozzles10forming the nozzle row109on the left side are the first nozzles and the nozzles10forming the nozzle row109on the right side are the second nozzles, the predetermined number N6acorresponds to the “first predetermined number” of the present disclosure, and the predetermined number N5acorresponds to the “second predetermined number” of the present disclosure.

In the fourth embodiment, in a case where the number N5of abnormal nozzles is less than the predetermined number N5aand the number N6of normal nozzles is less than the predetermined number N6a, the recording is performed by ejecting the ink from the nozzles10forming both of the nozzle rows109. As a result, recording with a high resolution in the conveying direction or the scanning direction can be performed.

On the other hand, in a case where the number N5of abnormal nozzles is equal to or greater than the predetermined number N5aand the number N6of abnormal nozzles is less than the predetermined number N6a, the recording is performed by not ejecting the ink from the nozzles10forming the nozzle row109on the right side and ejecting the ink from the nozzles10forming the nozzle row109on the left side. In a case where the number N5of abnormal nozzles is less than the predetermined number N5aand the number N6of abnormal nozzles is equal to or greater than the predetermined number N6a, the recording is performed by not ejecting the ink from the nozzles10forming the nozzle row109on the left side and ejecting the ink from the nozzles10forming the nozzle row109on the right side. As a result, in a case where the number of abnormal nozzles, among the nozzles10used when the ink is ejected based on the recording data, is equal to or greater than a predetermined number in one of the nozzle rows109and less than a predetermined number in the other of the nozzle rows, the recording can be performed with a lower resolution, in the conveying direction or the scanning direction, with simple processing. In this case, since the image quality of the recorded image is uniformly lowered, as compared with the case where the image quality of the recorded image is partially lowered by performing the recording without lowering the resolution and not ejecting the ink from the abnormal nozzle, the degradation in image quality is less noticeable.

Fifth Embodiment

Next, a preferred fifth embodiment of the present disclosure will be described. The fifth embodiment relates to the printer1similar to that of the first embodiment. However, in the fifth embodiment, the recording can be selectively performed in either a monochrome mode or a color mode in the printer1. The monochrome mode is a mode in which black ink is stored in all of the four ink cartridges14mounted in the cartridge holder13, and the black ink is ejected from all of the plurality of nozzles10of the ink jet head4to perform monochrome recording. The color mode is a mode in which black ink, yellow ink, cyan ink, and magenta ink are stored in the four ink cartridges14mounted in the cartridge holder13as described in the first embodiment, and the four colors of ink are ejected from the plurality of nozzles10of the ink jet head4to perform color recording.

In the fifth embodiment, in order to switch from the color mode to the monochrome mode, for example, among the four ink cartridges14mounted in the cartridge holder13, three ink cartridges14on the left side storing the color ink are removed, and ink cartridges14storing black ink are mounted instead. Then, suction purge is performed to replace, with black ink, the color ink in the ink jet head4, the sub-tank3, and the tube15.

In addition, in order to switch from the monochrome mode to the color mode, for example, among the four ink cartridges14mounted in the cartridge holder13, three ink cartridges14on the left side storing black ink are removed, and ink cartridges14storing color ink are mounted instead. Then, the suction purge is performed to replace, with color ink, the black ink in the ink jet head4, the sub-tank3, and the tube15. However, since the black ink is darker than the color ink, color ink of appropriate colors may not be ejected from the nozzles10even in such a case. Therefore, the printer according to the fifth embodiment may be configured to be switched from the monochrome mode to the color mode and not configured to be switched from the color mode to the monochrome mode.

In the fifth embodiment, the plurality of nozzles10configuring any one of the four nozzle rows9correspond to the “first nozzles” of the present disclosure. In addition, the plurality of nozzles10configuring any one of three nozzle rows9, excluding the nozzle row9configured by the above-mentioned first nozzles10, correspond to the “second nozzles” of the present disclosure. Further, the plurality of nozzles10configuring one of two nozzle rows9, excluding the nozzle row9configured by the above-mentioned first nozzles and the nozzle row9configured by the above-mentioned second nozzles, correspond to “third nozzles” of the present disclosure, and the plurality of nozzles10configuring the other of the two nozzle rows9correspond to “fourth nozzles” of the present disclosure.

In the fifth embodiment, the four ink cartridges14correspond to the “liquid storage portions” of the present disclosure. In addition, the ink cartridges14corresponding to the first to fourth nozzles correspond to the “first liquid storage portion”, the “second liquid storage portion”, a “third liquid storage portion”, and a “fourth liquid storage portion” of the present disclosure, respectively.

Flow paths and the tubes15in the ink jet head4and the sub-tank3, which connect the first nozzle and the ink cartridge14serving as the first liquid storage portion, correspond to the “first flow paths” of the present disclosure. Flow paths and the tubes15in the ink jet head4and the sub-tank3, which connect the second nozzle and the ink cartridge14serving as the second liquid storage portion, correspond to the “second flow paths” of the present disclosure. Flow paths and the tubes15in the ink jet head4and the sub-tank3, which connect the third nozzle and the ink cartridge14serving as the third liquid storage portion, correspond to the “third flow paths” of the present disclosure. Flow paths and the tubes15in the ink jet head4and the sub-tank3, which connect the fourth nozzle and the ink cartridge14serving as the fourth liquid storage portion, correspond to the “fourth flow paths” of the present disclosure.

In the fifth embodiment, in a case where the recording on the recording sheet P is performed in the printer1, the controller80performs processing with reference to a flow shown inFIGS.14A and14B. The flow shown inFIGS.14A and14Bwill be described in more detail. First, the controller80is configured to determine whether the mode is the monochrome mode (step S401). In the fifth embodiment, for example, information indicating whether the mode is the monochrome mode or the color mode is stored in the flash memory84in advance, based on an operation of the operation unit68by the user. Then, in step S401, the controller80determines whether the mode is the monochrome mode, based on the above-mentioned information stored in the flash memory84. Alternatively, for example, the ink cartridge14may include an IC chip in which color information of the stored ink is stored, and the cartridge holder13may include a reading unit configured to read information from the IC chip. Then, in step S401, the controller80may determine whether the mode is the monochrome mode, based on the color information of the ink stored in each ink cartridge14read from the IC chip via the reading unit.

In a case where the mode is not the monochrome mode, that is, in a case where the mode is the color mode (NO in step S401), the processing proceeds to step S412. In a case where the mode is the monochrome mode (YES in step S401), the controller80determines whether the number N7of abnormal nozzles in the rightmost nozzle row9is equal to or greater than a predetermined number N7a, based on the abnormal nozzle information stored in the flash memory84(step S402). Here, the predetermined number N7amay be one or two or more.

In a case where the number N7of abnormal nozzles is less than the predetermined number N7a(NO in step S402), the processing directly proceeds to step S404. In a case where the number N7of abnormal nozzles is equal to or greater than the predetermined number N7a(YES in step S402), the controller80sets the rightmost nozzle row9to non-use (step S403), and the processing proceeds to step S404.

In step S404, the controller80determines whether the number N8of abnormal nozzles in a second nozzle row9from the right is equal to or greater than a predetermined number N8a, based on the abnormal nozzle information stored in the flash memory84. Here, the predetermined number N8amay be one or two or more. In addition, the predetermined number N8amay be the same as the predetermined number N7a, or may be different from the predetermined number N7a.

In a case where the number N8of abnormal nozzles is less than the predetermined number N8a(NO in step S404), the processing directly proceeds to step S406. In a case where the number N8of abnormal nozzles is equal to or greater than the predetermined number N8a(YES in step S404), the controller80sets the second nozzle row9from the right to non-use (step S405), and the processing proceeds to step S406.

In step S406, the controller80determines whether the number N9of abnormal nozzles in a second nozzle row9from the left is equal to or greater than a predetermined number N9a, based on the abnormal nozzle information stored in the flash memory84. Here, the predetermined number N9amay be one or two or more. In addition, the predetermined number N9amay be equal to any one of the predetermined numbers N7aand N8a, or may be different from any one of the predetermined numbers N7aand N8a.

In a case where the number N9of abnormal nozzles is less than the predetermined number N9a(NO in step S406), the processing directly proceeds to step S408. In a case where the number N9of abnormal nozzles is equal to or greater than the predetermined number N9a(YES in step S406), the controller80sets the second nozzle row9from the left to non-use (step S407), and the processing proceeds to step S408.

In step S408, the controller80determines whether the number N10of abnormal nozzles in the leftmost nozzle row9is equal to or greater than a predetermined number N10a, based on the abnormal nozzle information stored in the flash memory84. Here, the predetermined number N10amay be one or two or more. In addition, the predetermined number N10amay be equal to any one of the predetermined numbers N7a, N8a, and N9a, or may be different from any one of the predetermined numbers N7a, N8a, and N9a.

In a case where the number N10of abnormal nozzles is less than the predetermined number N10a(NO in step S408), the processing directly proceeds to step S410. In a case where the number N10of abnormal nozzles is equal to or greater than the predetermined number N10a(YES in step S408), the controller80sets the leftmost nozzle row9to non-use (step S409), and the processing proceeds to step S410.

In the fifth embodiment, among the predetermined numbers N7a, N8a, N9a, and N10a, those corresponding to the first nozzle correspond to the “first predetermined number” of the present disclosure, and those corresponding to the second nozzle correspond to the “second predetermined number” of the present disclosure.

In step S410, the controller80determines whether all of the nozzle rows9are set to non-use. In a case where none of the nozzle rows9is set to non-use or only a part of the nozzle rows9are set to non-use (NO in step S410), the processing directly proceeds to step S412. In a case where all of the nozzle rows9are set to non-use (YES in S410), the controller80cancels a setting of non-use of a nozzle row9having the smallest number of abnormal nozzles among the four nozzle rows9(step S411), and the processing proceeds to step S412.

In step S412, the controller80performs a recording processing. In the recording processing, the controller80is configured to repeatedly perform the recording pass and the conveying operation as described above to perform the recording on the recording sheet P. In addition, in a case where the recording pass is performed in the recording processing, the controller80causes only the nozzles10forming the nozzle row9that is not set to non-use to eject the ink.

In the fifth embodiment, by performing the processing with reference to the flow shown inFIGS.14A and14B, in the monochrome mode, in a case where the number of abnormal nozzles in all of the nozzle rows9is less than the predetermined number, the recording is performed by ejecting the ink from the nozzles10forming the four nozzle rows9. In addition, in the monochrome mode, in a case where there are nozzle rows9in which the number of abnormal nozzles is equal to or greater than the predetermined number, the recording is performed by ejecting the ink only from the nozzles10forming a part of the four nozzle rows9. On the other hand, in the color mode, the recording is performed by ejecting the ink from the nozzles10forming the four nozzle rows9, regardless of the number of abnormal nozzles in each nozzle row9.

In the fifth embodiment, in the printer configured to selectively perform the recording in either the monochrome mode in which the recording is performed by ejecting black ink from all the nozzles forming the four nozzle rows9or the color mode in which the recording is performed by ejecting ink of different colors from the nozzles forming the four nozzle rows9, in a case where the recording is performed in the monochrome mode, when the number of abnormal nozzles among the first nozzles is less than the first predetermined number and the number of abnormal nozzles among the second nozzles is less than the second predetermined number, the recording can be performed, with a high resolution in the scanning direction, by driving the ink jet head4such that the ink is ejected from both the first nozzles and the second nozzles.

In a case where the number of abnormal nozzles among the first nozzles is equal to or greater than the first predetermined number and the number of abnormal nozzles among the second nozzles is less than the second predetermined number, the recording is performed by driving the ink jet head4such that the ink is not ejected from the first nozzles and the ink is ejected from the second nozzles. As a result, the recording can be performed with a lower resolution in the scanning direction.

In this case, in a case where the number of abnormal nozzles among the first nozzles is equal to or greater than the first predetermined number, the recording can be performed with a lower resolution in the scanning direction with a simple processing. In this case, since the image quality of the recorded image is uniformly lowered, as compared with the case where the image quality of the recorded image is partially lowered by performing the recording without lowering the resolution in the scanning direction and not ejecting the ink from the abnormal nozzle, the degradation in image quality is less noticeable.

In a case where the recording is performed in the color mode, the recording is performed by ejecting the ink from the nozzles10forming all of the nozzle rows9, regardless of the number of abnormal nozzles in each nozzle row9. Since ink of different colors are ejected from the nozzles10forming the four nozzle rows9in the color mode, in a case where ink is not ejected from only the nozzles10that eject a specific color of ink, there is a concern that the image quality may be greatly deteriorated compared to when ink is not ejected from the nozzles10forming a part of the nozzle rows9in the monochrome mode. Therefore, in the case of the color mode, even in a case where the number of abnormal nozzles in the nozzle row9is large, it is desirable to perform the recording by ejecting the ink from the nozzles10forming the nozzle row9.

Sixth Embodiment

Next, a preferred sixth embodiment of the present disclosure will be described. The sixth embodiment relates to the printer200similar to the second embodiment or the printer300similar to the third embodiment. In the sixth embodiment, in a case where recording is performed in the printer1, the controller80performs processing with reference to a flow shown inFIGS.15A and15B.

More specifically, the controller80is configured to perform the processing of step S201to step S204as described in the second embodiment. After the processing of step S204, the controller80determines whether there is a nozzle row109set to non-use (step S501).

In a case where there is no nozzle row109set to non-use (NO in step S501), the controller80performs the recording processing of step S207as described in the second embodiment, and ends the processing. In a case where there is a nozzle row109set to non-use (YES in step S501), the controller80performs screen display processing (step S502). In the screen display processing, the controller80causes the display unit69to display a selection screen250as illustrated inFIG.16. The selection screen250includes a message portion251(“first object” of the present disclosure) and selection portions252aand252b(“second object” of the present disclosure).

The message portion251is a portion where a message for notifying the user that recording is to be performed with a low resolution in order to prevent deterioration in image quality due to an ejection abnormality and for prompting the user to select whether to perform the recording with a low resolution is displayed. The selection portions252aand252bare portions in which the user select whether to record with a low resolution by operating the portions. In a case where the user operates the operation unit68based on the selection portion252a, a selection signal indicating that the recording is to be performed with a low resolution is input. In a case where the user operates the operation unit68based on the selection portion252b, a selection signal indicating that the recording is not performed with a low resolution is input. Here, operating the operation unit68based on the selection portions252aand252bmeans, for example, operating buttons corresponding to the selection portions252aand252bin a case where the operation unit68is a button, or touching a portion of a touch panel on which the selection portions252aand252bare displayed in a case where the operation unit68is the touch panel provided on the display unit69.

Returning toFIGS.15A and15B, after the selection screen display processing in step S502, the controller80is configured to wait until a selection signal is received (NO in step S503). In a case where the controller80receives the selection signal (YES in step S503), the controller80determines whether it is selected to perform the recording with a low resolution (step S504), based on the received selection signal.

In a case where it is selected to perform the recording with a low resolution (YES in step S504), the controller80performs the processing of step S205to step S207as described in the second embodiment. In a case where it is selected not to perform the recording with a low resolution (NO in step S504), the controller80cancels a setting of non-use of the nozzle row9set in at least one of step S202and step S204(step S505), and the processing proceeds to the recording processing of step S207. In this case, in the recording processing of step S207, the ink is ejected from the nozzles10forming both of the two nozzle rows109.

In the sixth embodiment, in a case where the number of abnormal nozzles in any of the nozzle rows109is large and the recording is performed with a low resolution by setting the nozzle row109to non-use, the selection screen250including the message portion251is displayed on the display unit69. As a result, the user can grasp that the recording is performed with a lower resolution.

In the sixth embodiment, in this case, the selection screen250including the message portion251and the selection portions252aand252bis displayed on the display unit69. Thus, in a case where the number of abnormal nozzles in any one of the nozzle rows109is equal to or greater than the predetermined number, the user can select whether to perform the recording with a lower resolution, and the recording can be performed with a lower resolution only when the user selects to perform the recording with a lower resolution.

On the other hand, in a case where the user selects not to perform the recording with a lower resolution, it is possible to perform the recording with a high resolution by ejecting the ink from the nozzles10forming both the nozzle rows109according to a preference of the user.

In the sixth embodiment, although an example has been described in which the selection screen250is displayed on the display unit69to allow the user to select whether to perform the recording with a lower resolution in the second and third embodiments, the selection screen250may be displayed on the display unit69to allow the user to select whether to perform the recording with a lower resolution in the first and fourth embodiments.

In the first to sixth embodiments, in a case where the recording is performed with a lower resolution, the size of the dots is increased by increasing the amount of ink ejected from the nozzles10compared to a case where the resolution is not lowered, but the present invention is not limited thereto. In the case where the recording is performed with a lower resolution, the amount of ink ejected from the nozzles10may be the same as that in the case where the resolution is not lowered.

In the first embodiment, the low resolution set in advance is uniformly lower than an original resolution regardless of a portion of the recorded image, but the present invention is not limited thereto. The low resolution set in advance may vary depending on the position, in the conveying direction, of the recorded image. For example, in the conveying direction, among the plurality of dots D formed in a case where the recording is performed by the first recording processing, control may be performed such that two consecutive dots are formed and the next two consecutive dots are thinned out, or control may be performed such that, for example, three consecutive dots are formed and the next three consecutive dots are thinned out, instead of forming every other dot D.

In the first embodiment, in a case where the number N2of abnormal nozzles cannot be made less than the predetermined number Na even when the recording is performed with the low resolution set in advance, the first recording processing is performed after the suction purge is performed, but the present invention is not limited thereto. For example, in such a case, a message prompting to perform the suction purge may be displayed on the display unit69without performing the recording.

In the second and third embodiments, in a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3aand the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, the recording is performed by ejecting the ink only from the nozzles10forming the nozzle row109having a smaller number of abnormal nozzles among the two nozzle rows109, but the present invention is not limited thereto.

In the second and third embodiments, in a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3aand the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, the recording may be performed by ejecting the ink only from the nozzles10forming the nozzle row109on the right side, regardless of a magnitude relation between the number N3of abnormal nozzles and the number N4of abnormal nozzles. Alternatively, the recording may be performed by ejecting the ink only from the nozzles10forming the nozzle row109on the left side, regardless of the magnitude relation between the number N3of abnormal nozzles and the number N4of abnormal nozzles.

Alternatively, in the second and third embodiments, in a case where the number N3of abnormal nozzles is equal to or greater than the predetermined number N3aand the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, the suction purge may be performed, the setting of non-use of both of the nozzle rows109may be canceled, and then the processing may proceed to the recording processing of step S207.

In the second and third embodiments, the ink is supplied, from different ink cartridges114, to the plurality of nozzles10forming the nozzle row109on the right side and the plurality of nozzles10forming the nozzle row109on the left side. However, the present invention is not limited thereto. For example, the ink may be supplied from a common ink cartridge114to the plurality of nozzles10forming the two nozzle rows109.

In the above example, the ink is supplied to the nozzles10from the detachably mounted ink cartridge, but the present invention is not limited thereto. For example, the printer may be provided not to be detachable, an ink tank having an ink replenishment port may be provided, and ink stored in the ink tank may be supplied to each nozzle10.

In the second and third embodiments, the plurality of first driving elements120aare driven by the first driver IC130a, and the plurality of second driving elements120bare driven by the second driver IC130bdifferent from the first driver IC130a, but the present invention is not limited thereto. For example, the plurality of first driving elements120aand the plurality of second driving elements120bmay be driven by a common driver IC.

In the second embodiment, the ink jet head4has two nozzle rows109, and, between the two nozzle rows109, the positions, in the conveying direction, of the nozzles10are shifted by half the length of the interval Lb between the nozzles10in each nozzle row109, but the present invention is not limited thereto. For example, assuming that M is an integer of three or more, the ink jet head may have M nozzle rows109, and positions, in the conveying direction, of the nozzles10may be shifted between the nozzle rows109by a length (Lb/M) of 1/M of the interval Lb of the nozzles10in each nozzle row109.

In the fifth embodiment, the positions, in the conveying direction, of the nozzles10in the four nozzle rows9are the same, but the present invention is not limited thereto. In the fifth embodiment, the positions, in the conveying direction, of the nozzles10in at least a part of the four nozzle rows9may be shifted.

In addition, in the fifth embodiment, in a case where all of the four nozzle rows9are set to non-use, the recording is performed by canceling the setting of non-use of one nozzle row9having the smallest number of abnormal nozzles, but the present invention is not limited thereto. For example, in a case where all of the four nozzle rows9are set to non-use, the recording may be performed by canceling the setting of non-use in two nozzle rows9including the nozzle row9having the smallest number of abnormal nozzles and a nozzle row9having the second smallest number of abnormal nozzles. Alternatively, for example, in a case where all of the four nozzle rows9are set to non-use, the recording may be performed by canceling the setting of non-use of three nozzle rows9other than a nozzle row9having the largest number of abnormal nozzles.

In the sixth embodiment, in a case where any one of the nozzle rows9is set to non-use and the user selects not to perform the recording with a lower resolution, the setting of non-use of the nozzle row9is canceled, and the recording is performed by ejecting the ink from the plurality of nozzles10forming both of the nozzle rows9in a state where at least the number N3of abnormal nozzles is equal to or greater than the predetermined number N3aor the number N4of abnormal nozzles is equal to or greater than the predetermined number N4a, but the present invention is not limited thereto.

For example, in a case where any one of the nozzle rows9is set to non-use and the user selects not to perform the recording with a lower resolution, the recording may be performed by ejecting the ink from the plurality of nozzles10forming both of the nozzle rows9after the suction purge is performed. Alternatively, in such a case, the recording may be stopped and a message prompting to perform the suction purge may be displayed on the display unit69.

In the sixth embodiment, the selection screen250including the message portion251and the selection portions252aand252bis displayed on the display unit69, but the present invention is not limited thereto. For example, instead of the selection screen250, a screen including only a message for notifying the user that the recording is to be performed with a lower resolution may be displayed on the display unit69. In this case as well, the user can grasp that the recording is performed with a lower resolution based on this screen.

The screen as described above is not limited to being displayed on the display unit of the printer. For example, in a case where the printer is connected to an external device such as a PC or a smartphone, a screen as described above may be displayed on a display unit of the external device. In this case, for example, the controller80may transmit a signal for displaying the screen to the external device instead of performing processing of displaying the screen on the display unit69.

The recording may be performed with a lower resolution without displaying the screen as described above on the display unit.

In the above example, the resolution, in the conveying direction or the scanning direction, of the recorded image in the second recording processing is set to be lower than that in the first recording processing, but the present invention is not limited thereto.

For example, in the second recording processing of the first and second embodiments, a conveyance amount of the recording sheet P in the conveying operation is set to be smaller than that in the first recording processing, and the ink ejection corresponding to one recording pass in the first recording processing among the recording data is performed in a plurality of recording passes separately, and thus the resolution, in the conveying direction, of the recorded image may be the same as that in the case where the recording is performed by the first recording processing. In this case, in the second recording processing, since the ink ejection corresponding to one recording pass in the first recording processing among the recording data is only performed in a plurality of recording passes separately, the recording can be performed by directly using the recording data used in the first recording processing. Therefore, processing of changing from the first recording processing to the second recording processing is not complicated. That is, the control can be simplified. In the fourth and sixth embodiments, even in the second recording processing in a case where the positions, in the conveying direction, of the nozzles10are shifted between the two nozzle rows109, the recording may be performed in the same manner as described above.

For example, in the second recording processing of the third embodiment, in the recording pass, a movement speed of the carriage2may be set to half a speed in the first recording processing, and ink ejection, from the nozzles10forming the one of the nozzle rows109, based on a data portion corresponding to one of the nozzle rows109in the recording and based on a data portion corresponding to the other of the nozzle rows109in the recording data may be alternately performed. In this case, the resolution, in the scanning direction, of the image recorded in the second recording processing is the same as that in the case where the recording is performed by the first recording processing. In this case, in the second recording processing, since the recording can be performed by directly using the recording data used in the first recording processing, the processing of changing from the first recording processing to the second recording processing is not complicated. That is, the control can be simplified. In the second recording processing in a case where the positions, in the conveying direction, of the nozzles10are the same between the two nozzle rows109in the fourth and sixth embodiments, and in the second recording processing in the fifth embodiment, the recording may be performed in the same manner as described above.

In the above example, it is determined whether the nozzle10is an abnormal nozzle, based on the signal output from the signal processing circuit78according to a change in voltage from the nozzle10to the electrode76disposed inside the cap71in a case where the ink jet head4is caused to perform the test drive, but the present invention is not limited thereto.

For example, instead of the electrode76, an electrode that extends in the vertical direction and faces a space below the nozzle10in a state where the carriage2is positioned at the maintenance position may be provided. The signal processing circuit78may be configured to output a signal corresponding to the change in voltage of the above-mentioned electrode in a case where the test drive is performed in the state where the carriage2is positioned at the maintenance position.

Alternatively, for example, an optical sensor configured to directly detect the ink ejected from the nozzles10in the state where the carriage2is positioned at a predetermined position such as the maintenance position and configured to output a signal corresponding to a detection result may be provided. Whether the nozzle10is an abnormal nozzle may be determined based on the signal output from the optical sensor.

Alternatively, for example, similar to that described in JP 4929699 B2, a voltage detection circuit configured to detect a change in voltage in a case where ink is ejected from a nozzle may be connected to a plate in which the nozzle of an ink jet head is formed, and whether the nozzle is an abnormal nozzle may be determined based on a signal output from the voltage detection circuit in a case where an operation for ejecting the ink from the nozzle is performed in a state where a carriage is moved to a test position.

Alternatively, for example, similar to that described in JP 6231759 B2, a substrate of an ink jet head may include a temperature detection element. After a heater is driven by applying a first applied voltage for ink ejection, the heater may be driven by applying a second applied voltage such that the ink is not ejected, and a signal corresponding to whether the nozzle10is an abnormal nozzle may be output, based on a change in temperature detected by the temperature detection element until a predetermined time elapses after the second applied voltage is applied.

Alternatively, a predetermined test pattern may be recorded in the printer, and whether each nozzle10is an abnormal nozzle may be determined based on a recording result of the test pattern. In this case, in a case where the printer is a multi function device having a scanner, the recording result of the test pattern may be input by causing the scanner to read the test pattern. Alternatively, the user may input the recording result of the test pattern by operating the operation unit68or an external device connected to the printer, based on the recording result of the test pattern.

In the above example, the test drive is performed for all the nozzles10of the ink jet head4to determine whether the nozzles10are abnormal nozzles, but the present invention is not limited thereto. For example, it may be determined whether the nozzle10is an abnormal nozzle by performing the test drive only for a part of nozzles10of the ink jet head4, such as every other nozzle10in each nozzle row9. Then, for other nozzles10, it may be estimated whether the nozzle10is an abnormal nozzle based on a determination result for the part of the nozzles10.

In the above example, it is determined whether the nozzle10is an abnormal nozzle based on whether the ink is ejected from the nozzle10, but the present invention is not limited thereto. For example, it may be determined whether the nozzle10is an abnormal nozzle based on an ejection direction or an ejection speed of the ink.

In the above example, as the abnormal nozzle information, information as to whether each of the plurality of nozzles10is an abnormal nozzle is stored in the flash memory84, but other information related to whether there are abnormal nozzles having a predetermined number or more of abnormal nozzles may be stored in the flash memory84, as the abnormal nozzle information. For example, information on the number of abnormal nozzles may be stored in the flash memory84, as the abnormal nozzle information. In addition, for example, in each embodiment, in a case where all the predetermined numbers are one, information on whether at least one nozzle10is an abnormal nozzle may be stored in the flash memory84, as the abnormal nozzle information.

In the above-described embodiment, an example in which the present disclosure is applied to a printer including a so-called serial head configured to eject ink from a plurality of nozzles while moving in the scanning direction together with a carriage has been described, but the present invention is not limited thereto. For example, the present disclosure can be applied to a printer including a so-called line head having a plurality of nozzles extending over the entire length of a recording sheet in the scanning direction (“first direction” of the present disclosure) and arranged in the scanning direction. In the printer including the line head, recording is performed by ejecting ink from a plurality of nozzles of the line head while relatively moving the line head, with respect to the recording sheet, in the conveying direction by conveying the recording sheet in the conveying direction (“second direction” of the present disclosure) by a sheet conveying mechanism such as a conveying roller. That is, in a case where the present disclosure is applied to the printer including the line head, the sheet conveying mechanism corresponds to the “relative movement unit” of the present disclosure.

As described above, an example in which the present disclosure is applied to an external device configured to communicate with a printer configured to perform recording on a recording sheet P by ejecting ink from nozzles has been described, but the present invention is not limited thereto. The present disclosure can also be applied to a printer configured to record an image on a recording medium other than a recording sheet, such as a T-shirt, a sheet for outdoor advertisement, a case of a mobile terminal such as a smartphone, a corrugated board, and a resin member.