阅读说明：本技术 记录装置以及记录头的错误判断方法 (Recording apparatus and method for determining error of recording head ) 是由 本田贤一 于 2020-03-18 设计创作，主要内容包括：本发明提供一种记录装置以及记录头的错误判断方法,其防止了与记录头的实际状态相反地判断为记录的继续执行为不适当的情况。记录装置具备：记录头,其具有多个由用于喷出相同颜色的油墨的多个喷嘴而构成的喷嘴列；检测部,其对所述喷嘴中的成为了喷出不良的不良喷嘴进行检测；控制部,其基于由所述检测部所获得的检测结果,来对所述记录头是否处于错误状态进行判断,所述控制部在所述记录头中处于能够对相互的喷出进行补全的特定的位置关系的多个喷嘴中的、大于1的预定数量以上的喷嘴为所述不良喷嘴的情况下,判断为处于所述错误状态。(The invention provides a recording apparatus and an error judgment method of a recording head, which prevent the situation that the continuous execution of the recording is judged to be inappropriate contrary to the actual state of the recording head. The recording device includes: a recording head having a plurality of nozzle rows each including a plurality of nozzles for ejecting ink of the same color; a detection unit that detects a defective nozzle that has caused a discharge failure among the nozzles; and a control unit that determines whether or not the recording head is in an error state based on a detection result obtained by the detection unit, wherein the control unit determines that the recording head is in the error state when a predetermined number of or more nozzles greater than 1 among a plurality of nozzles in the recording head that are in a specific positional relationship capable of complementing the mutual ejection are the defective nozzles.)

1. A recording apparatus is characterized by comprising:

a recording head having a plurality of nozzle rows configured by a plurality of nozzles for ejecting ink of the same color;

a detection unit that detects a defective nozzle that has a defective ejection from among the nozzles;

a control section that determines whether or not the recording head is in an error state based on a detection result obtained by the detection section,

the control unit determines that the error state is present when a predetermined number of or more nozzles greater than 1 among a plurality of nozzles in a specific positional relationship in which the recording head can compensate for the mutual ejection are the defective nozzles.

2. The recording apparatus of claim 1,

the control unit sets the plurality of nozzles belonging to the different nozzle rows and located at positions where recording can be performed on the common grid line as the plurality of nozzles in the specific positional relationship.

3. The recording apparatus according to claim 1 or 2,

the recording head includes, as the nozzle rows, a first nozzle row and a second nozzle row which are arranged so that positions of nozzles are shifted from each other in a nozzle row direction which is a nozzle arrangement direction,

the control unit sets a plurality of nozzles in the specific positional relationship to each other as a first nozzle which is a nozzle belonging to the first nozzle row and a second nozzle which is a nozzle belonging to the second nozzle row, and the first nozzle and the second nozzle which are adjacent in the nozzle row direction, and determines that the error state is present when the first nozzle and the second nozzle which are adjacent in the nozzle row direction are both the defective nozzles.

4. An error determination method for a recording head, comprising:

a detection step of detecting a defective nozzle that has a discharge failure among nozzles of a recording head having a plurality of nozzle rows configured by the plurality of nozzles for discharging ink of the same color;

a determination step of determining whether or not the recording head is in an error state based on a detection result obtained by the detection step,

in the determining step, the error state is determined when a predetermined number of or more than 1 of the plurality of nozzles in the recording head, which are in a specific positional relationship capable of compensating for the mutual ejection, are the defective nozzles.

Technical Field

The invention relates to a recording apparatus and an error determination method for a recording head.

Background

Although a plurality of nozzles are provided in a recording head of an ink jet printer, the nozzles may be clogged due to an increase in the viscosity of ink, mixing of air bubbles, or the like. When the nozzles are clogged, the printer discharges ink while controlling the discharge of ink from the nozzles, but the ink is not actually discharged or discharged in a required amount, and a defective recording portion of dots, that is, a "missing dot" is generated in the recording result on the recording medium. Since missing dots become a problem in order to obtain good recording quality, it is necessary to perform a missing dot inspection.

As a related art, a liquid ejecting apparatus having a test pattern forming section that forms a test pattern by liquid ejected from a plurality of ejection nozzles of a liquid ejecting head is disclosed (see patent document 1).

When a missing dot is detected from the recording result of the test pattern, the printer makes a judgment indicating that the continuation of recording is not appropriate. However, in the case of a printer having a plurality of nozzle rows capable of ejecting ink of the same color, there is a case where recording can be continuously performed even if some of the nozzles are clogged. That is, in the conventional printer, although recording can be actually continued, it may be determined from the recording result of the test pattern that the continued recording is not appropriate.

Patent document 1: japanese patent laid-open publication No. 2005-35102

Disclosure of Invention

The recording device includes: a recording head having a plurality of nozzle rows configured by a plurality of nozzles for ejecting ink of the same color; a detection unit that detects a defective nozzle that has caused a discharge failure among the nozzles; and a control unit that determines whether or not the recording head is in an error state based on a detection result obtained by the detection unit, wherein the control unit determines that the recording head is in the error state when a predetermined number of or more nozzles greater than 1 among a plurality of nozzles in the recording head that are in a specific positional relationship capable of complementing the mutual ejection are the defective nozzles.

Drawings

Fig. 1 is a block diagram simply showing the configuration of the apparatus.

Fig. 2 is a diagram showing a nozzle arrangement of the first embodiment.

Fig. 3 is a flowchart showing the error determination processing of the first embodiment.

Fig. 4 is a diagram showing a nozzle arrangement of the second embodiment.

Fig. 5 is a flowchart showing the error determination processing of the second embodiment.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawings are merely examples for explaining the present embodiment. Since the drawings are examples, there may be a case where they do not match each other or a part is omitted.

1. Brief description of the device:

fig. 1 simply shows the configuration of a recording apparatus 10 according to the present embodiment. The recording apparatus 10 may be described as a liquid ejecting apparatus, a printing apparatus, a printer, or the like. The recording device 10 executes the error determination method according to the present embodiment. The recording apparatus 10 includes a control unit 11, a display unit 13, an operation receiving unit 14, a recording head 15, a conveying unit 16, a defective nozzle detecting unit 21, and the like. The control unit 11 includes one or more ICs (integrated circuits) including a CPU11a, a ROM11b, a RAM11c, and the like as processors, or other nonvolatile memories.

The CPU11a serving as a processor of the control unit 11 controls the recording apparatus 10 by using the RAM11c or the like as a work area and executing arithmetic processing in accordance with a program stored in the ROM11b or another memory or the like. The control unit 11 executes processing performed in accordance with firmware 12, which is one type of program, for example. The processor is not limited to one CPU, and may be configured to perform processing by a plurality of hardware circuits such as CPUs, ASICs (Application Specific integrated circuits), or the like, or may be configured to perform processing by cooperating the CPUs and the hardware circuits.

The display unit 13 is a unit for displaying visual information, and is configured by, for example, a liquid crystal display, an organic EL (Electro Luminescence) display, or the like. The display unit 13 may include a display and a driving circuit for driving the display. The operation receiving unit 14 is means for receiving an operation performed by a user, and is implemented by, for example, a physical button, a touch panel, a keyboard, or the like. Of course, the touch panel may be implemented as one function of the display unit 13. The display unit 13 and the operation receiving unit 14 may be included together and referred to as an operation panel of the recording apparatus 10.

The conveying unit 16 is a mechanism for conveying a recording medium. As is known, the conveying section 16 includes a roller for conveying the recording medium from upstream to downstream of the conveying path, a motor for rotating the roller, and the like. The recording medium is typically paper, but may be a medium made of a material other than paper as long as it can perform recording by receiving ejection of a liquid.

The recording head 15 performs recording by ejecting ink by an ink jet method. As illustrated in fig. 2 or 4, the recording head 15 includes a plurality of nozzles 17 capable of ejecting ink, and the ink is ejected from the nozzles 17 toward the recording medium 30 conveyed by the conveying unit 16. The ink droplets ejected from the nozzles 17 are also called dots. The control unit 11 controls application of a drive signal to a drive element, not shown, included in the nozzle 17, thereby causing the dot to be ejected or not ejected from the nozzle 17.

The defective nozzle detecting unit 21 is a unit capable of performing a process of detecting a defective nozzle that becomes a discharge defect among the nozzles 17 included in the recording head 15. The defective nozzle is the nozzle 17 which has been controlled to discharge ink by applying a drive signal to the drive element provided in the nozzle 17 as described above, but is defective in discharge due to clogging or the like. The ejection failure includes a state where the dots cannot be ejected at all, and also includes a case where the amount of ejected liquid is too small. The defective nozzle may be referred to as an abnormal nozzle or the like. The nozzles 17 which are not defective nozzles are also referred to as normal nozzles.

2. Nozzle arrangement:

fig. 2 shows an arrangement example of the plurality of nozzles 17 provided in the recording head 15. A description on the premise of the nozzle arrangement in the recording head 15 shown in fig. 2 will also be referred to as a first embodiment. Further, fig. 2 simply shows the relationship between the recording head 15 and the recording medium 30.

The recording head 15 may be described as a liquid ejection head, a print head, or the like. In the example of fig. 2, the recording head 15 is mounted on a carriage 20 that is reciprocally movable parallel to a predetermined first direction D1, and moves together with the carriage 20. That is, although not shown in fig. 1, according to the example of fig. 2, the recording apparatus 10 includes the carriage 20, and the control unit 11 also controls the movement of the carriage 20.

The first direction D1 is also referred to as a main scanning direction. The conveying unit 16 conveys the recording medium 30 in a second direction D2 intersecting the first direction D1. The second direction D2 is also referred to as a sub-scanning direction or a conveying direction. The term "crossing" as used herein means orthogonal. In the present embodiment, the expressions parallel, orthogonal, fixed, and the same with respect to the direction, distance, and position may mean not only strictly parallel, orthogonal, fixed, and the same, but also include errors to the extent that the errors occur due to the precision of manufacturing or assembling of the components.

Reference numeral 19 denotes a nozzle surface 19 on which the nozzles 17 in the recording head 15 are opened. In fig. 2, an arrangement of a plurality of nozzles 17 in a nozzle face 19 is shown. In the configuration in which ink is supplied from an ink holding unit, not shown, called an ink cartridge or an ink tank, mounted on the recording apparatus 10 and is discharged from the nozzles 17, the recording head 15 includes nozzle rows each corresponding to a predetermined ink color. The single nozzle row is configured by the plurality of nozzles 17 which discharge the ink of the same color, with the plurality of nozzles 17 having a fixed nozzle pitch NP which is the interval between the nozzles 17 along the second direction D2. The recording head 15 ejects ink of a color such as cyan (C), magenta (M), yellow (Y), black (K), or white (W).

In the first embodiment, the recording head 15 includes nozzle rows 18W1, 18W2, 18W3, 18W4, 18W5, 18W6, 18W7, and 18W8 each including a plurality of nozzles 17 for discharging W ink. That is, all of the eight nozzle rows 18W1, 18W2, 18W3, 18W4, 18W5, 18W6, 18W7, and 18W8 are nozzle rows for ejecting W ink. In the recording head 15, a plurality of nozzle rows are arranged along the first direction D1. A colored image is recorded by ejecting a color ink from a recording head having nozzles capable of ejecting the color ink, which is located on the downstream side in the transport direction with respect to the recording head 15 of the first embodiment, to the area where the W ink is recorded by the recording head 15 of the first embodiment.

In the first embodiment, the positions of the nozzles 17 in the second direction D2 of every other nozzle row 18w1, 18w3, 18w5, 18w7 included in the recording head 15 are the same. In addition, the positions of the nozzles 17 in the second direction D2 in the other every other nozzle row 18w2, 18w4, 18w6, 18w8 are the same. In the first embodiment, the nozzle rows 18w1, 18w3, 18w5, 18w7 are each referred to as a first nozzle row, and the nozzle rows 18w2, 18w4, 18w6, 18w8 are each referred to as a second nozzle row.

The first nozzle row group, i.e., the nozzle rows 18w1, 18w3, 18w5, 18w7, is collectively referred to as a first nozzle row group. The group of the second nozzle rows, i.e., the nozzle rows 18w2, 18w4, 18w6, 18w8, are collectively referred to as a second nozzle row group. The first nozzle array group and the second nozzle array group are arranged so that the positions of the nozzles 17 are shifted from each other in the nozzle array direction by a distance equal to half of the nozzle pitch NP in the second direction D2. Therefore, when the first nozzle row and the second nozzle row are juxtaposed, the nozzles 17 are arranged at an interval of half the nozzle pitch NP in the second direction D2. In the example of fig. 2, the nozzle row direction and the second direction D2 are parallel. The nozzle row direction is a direction in which the plurality of nozzles 17 constituting the nozzle row are arranged.

Of course, the plurality of nozzle rows of the recording head 15 corresponding to the ejection of the ink of the same color may be more than eight rows or less than eight rows. Further, as long as the above-described features of the first nozzle array group and the second nozzle array group can be achieved, the nozzle array direction may be inclined with respect to the second direction D2.

The recording apparatus 10 can record on the recording medium 30 by alternately repeating conveyance of the recording medium 30 by a predetermined conveyance amount by the conveyance unit 16 and ink ejection by the recording head 15 with movement of the carriage 20.

The configuration for executing the error determination method according to the present embodiment can be realized not only by one independent apparatus but also by an information processing apparatus and a printer which are connected to each other so as to be able to communicate with each other. The information processing device is, for example, a personal computer, a smart phone, a tablet terminal, a mobile phone, a server, or a device having a processing capability comparable to those of these devices. That is, the recording apparatus 10 may be realized by an information processing apparatus as a recording control apparatus including the control unit 11 and the like, and a printer including the recording head 15, the carriage 20, the conveying unit 16, the defective nozzle detecting unit 21, and the like.

3. And (3) error judgment processing:

fig. 3 shows an error determination process according to the first embodiment, which is executed by the control unit 11 in accordance with the firmware 12, by way of a flowchart. The error determination process is a process of determining whether or not the recording head 15 is in a normal state for executing recording.

In step S100, the control unit 11 causes the defective nozzle detecting unit 21 to execute the defective nozzle detecting process, thereby obtaining the result of the defective nozzle detecting process. As the defective nozzle detection process, various methods can be employed as long as whether or not the defective nozzle is detected for each nozzle 17. For example, the defective nozzle detection unit 21 may detect a defective nozzle in the manner disclosed in japanese patent application laid-open No. 2013-126776. Specifically, whether or not the ink is normally discharged from the nozzle 17 is detected by measuring a waveform of a residual vibration of a so-called vibrating plate or the like that is bent in accordance with the deformation of the driving element (piezoelectric element) due to the application of the driving signal. The diaphragm is a part of the elements constituting the recording head 15, and is a portion deformed to extrude ink from the nozzle 17.

The defective nozzle detecting unit 21 positions the relative position between the light emitter and the recording head 15 so that, for example, the laser light emitted from the light emitter intersects with the ink flight path of the nozzle 17 to be inspected. Further, a laser system may be adopted in which, when the light-blocking of the laser light by the dot ejected from the nozzle 17 is not detected by the light-receiving device, the nozzle to be inspected is determined as a defective nozzle. In this way, the defective nozzle detecting section 21 drives each nozzle 17 to perform an ink discharge operation. The target of ink ejection may be the recording medium 30, or may be a member such as a maintenance box provided in the recording apparatus 10 to collect the ejected ink.

The defective nozzle detecting unit 21 performs a defective nozzle detecting process to generate defective nozzle information in which information on whether each of the nozzles 17 of the recording head 15 is a defective nozzle or a normal nozzle is described. The control unit 11 acquires such defective nozzle information. That is, in step S100, the control unit 11 acquires the latest defective nozzle information. In the present embodiment, the recording device 10 does not record a test pattern for evaluating the presence or absence of a missing dot on the recording medium 30 based on the recording result.

Step S100 corresponds to a detection step of detecting a defective nozzle that causes a discharge failure among the nozzles 17 of the recording head 15.

The steps below step S110 correspond to a determination step of determining whether or not the recording head 15 is in an error state based on the detection result detected in the detection step.

In step S110, the control unit 11 refers to the defective nozzle information to determine whether or not the completion by the nozzle 17 at the same position is possible. The "same position" mentioned in step S110 refers to a case where the positions in the second direction D2 are the same. It can be said that the plurality of nozzles 17 that are at the same position in the second direction D2 are in the "specific positional relationship that can complement each other's ejection". The compensation of the mutual ejection means that even if a missing dot is generated due to a defective ejection of one of the inks, the missing dot can be virtually visually confirmed by the ejection of the other ink. More specifically, the plurality of nozzles 17 having the same position in the second direction D2 belong to different nozzle rows and have a positional relationship in which recording can be performed on a common grid line. The grid lines refer to lines parallel to the first direction D1.

The nozzles 17 constituting the nozzle row are described by reference numerals. As a specific example, as shown in fig. 2, for each nozzle 17 constituting the nozzle row, integers of #1 to # N are given as the nozzle number in order from the downstream toward the upstream in the second direction D2. The nozzles 17 are assigned nozzle numbers #1 to # N for all nozzle rows. N is the number of nozzles constituting one nozzle row, and N is 6 in the example of fig. 2. Of course, the number of nozzles constituting the nozzle row is not limited, and in an actual product, N is, for example, several hundred.

In the nozzle arrays 18w1, 18w3, 18w5, 18w7 of the first nozzle array group, the positions of the nozzles 17 coincide with each other in the second direction D2. Therefore, in the first nozzle array group, the nozzles 17 having the same nozzle number have the same positional relationship with each other. Similarly, in the nozzle arrays 18w2, 18w4, 18w6, 18w8 of the second nozzle array group, the positions of the nozzles 17 coincide with each other in the second direction D2. Therefore, in the second nozzle array group, the nozzles 17 having the same nozzle number have the same positional relationship with each other. That is, in the first embodiment, when the first nozzle group and the second nozzle group are combined together, 2 × N positions can be grasped as the positions of the nozzles 17 in the second direction D2.

The control unit 11 determines whether or not the number of defective nozzles is equal to or greater than a predetermined number for each position of the nozzles 17 in the second direction D2 as described above. In the present embodiment, the "predetermined number" is an integer greater than 1. When referring to fig. 2, there are four nozzles 17 in the same position in the second direction D2. For example, the positions of the nozzles 17 in the second direction D2 of the total four nozzles with nozzle numbers #1 in each of the nozzle rows 18w1, 18w3, 18w5, and 18w7 are the same. Referring to the defective nozzle information, if, for example, three or more nozzles 17 out of the four nozzles 17 at the same position are defective nozzles, the control unit 11 determines that the number of defective nozzles is equal to or greater than a predetermined number with respect to the position. On the other hand, if the defective nozzles of the four nozzles 17 at the same position are less than three, it is determined that the number of defective nozzles is less than the predetermined number with respect to the position. The control unit 11 performs such determination for all the positions of the nozzles 17 in the second direction D2. When the number of defective nozzles is smaller than the predetermined number for all the positions of the nozzles 17 in the second direction D2, the control unit 11 determines that the completion can be performed by the nozzles 17 at the same position. On the other hand, when the number of defective nozzles is equal to or greater than the predetermined number for at least one position of the nozzles 17 in the second direction D2, the control unit 11 determines that the completion cannot be performed by the nozzles 17 at the same position.

In step S120, the control unit 11 branches the process based on the determination result obtained in step S110. That is, when determining that the completion can be performed by the nozzles 17 at the same position, the control unit 11 proceeds from the determination of yes in step S120 to step S130. On the other hand, when it is determined that the completion cannot be performed by the nozzle 17 at the same position, the process proceeds from the determination of no in step S120 to step S170.

In step S130, the control unit 11 refers to the defective nozzle information to determine whether or not the repair can be performed by the nozzles 17 in the vicinity. The "vicinity position" mentioned in step S130 refers to a positional relationship between the nozzles 17 belonging to the first nozzle row and the nozzles 17 belonging to the second nozzle row, and is adjacent in the nozzle row direction. For convenience of description, the nozzles 17 belonging to the first nozzle column are referred to as first nozzles, and the nozzles 17 belonging to the second nozzle column are referred to as second nozzles. The first nozzles and the second nozzles located in the vicinity can substantially complement each other in recording by spreading the dots ejected on the recording medium 30 by penetrating them. Therefore, it can be said that the first nozzle and the second nozzle at the adjacent positions are in "a specific positional relationship capable of compensating for the mutual discharge". Hereinafter, the first nozzle and the second nozzle located at the nearby positions are referred to as a "nearby nozzle pair".

According to the example of fig. 2, a first nozzle with a nozzle number # n and a second nozzle with a nozzle number # n correspond to one nearby nozzle pair. N is an integer of 1 to N. Further, according to the example of fig. 2, the first nozzle with the nozzle number # n and the second nozzle with the nozzle number # n +1 correspond to one nearby nozzle pair. Although the first nozzle row and the second nozzle row are four rows in the example of fig. 2, the adjacent nozzle pairs to be determined in step S130 are extracted only by the combination between the adjacent first nozzle row and second nozzle row. That is, the controller 11 extracts all the neighboring nozzle pairs from the nozzle row 18w1 and the nozzle row 18w 2. Similarly, the controller 11 extracts all the neighboring nozzle pairs from the nozzle row 18w3 and the nozzle row 18w4, extracts all the neighboring nozzle pairs from the nozzle row 18w5 and the nozzle row 18w6, and extracts all the neighboring nozzle pairs from the nozzle row 18w7 and the nozzle row 18w 8.

The control unit 11 determines whether or not both of the two nozzles 17 in the pair are defective nozzles for each of the adjacent nozzle pairs extracted as described above. The control unit 11 refers to the defective nozzle information, and if both of the two nozzles 17 constituting the nearby nozzle pair are defective nozzles, determines that the number of defective nozzles is equal to or greater than a predetermined number with respect to the nearby nozzle pair. On the other hand, if the defective nozzles of the two nozzles 17 constituting the nearby nozzle pair are less than two, it is determined that the number of defective nozzles is less than the predetermined number with respect to the nearby nozzle pair. The control unit 11 performs such determination for all the extracted pairs of neighboring nozzles. When the number of defective nozzles for all the extracted pairs of nearby nozzles is less than the predetermined number, the control unit 11 determines that the compensation can be performed by the nozzles 17 at the nearby positions. On the other hand, when the number of defective nozzles for at least one of the extracted pairs of nearby nozzles is equal to or greater than the predetermined number, the control unit 11 determines that the completion cannot be performed by the nozzles 17 at nearby positions.

The predetermined number used in the determination of step S110 may be referred to as a first predetermined number, and the predetermined number used in the determination of step S130 may be referred to as a second predetermined number, so that the distinction is made.

In step S140, the control unit 11 branches the process according to the determination result obtained in step S130. That is, when the control unit 11 determines that the completion can be performed by the nozzle 17 at the neighboring position, the determination of yes in step S140 proceeds to step S150. On the other hand, when it is determined that the completion cannot be performed by the nozzle 17 at the neighboring position, the process proceeds from the determination of no in step S140 to step S170.

In step S150, the control unit 11 refers to the defective nozzle information to determine whether or not the number of defective nozzles satisfies a predetermined normal condition. For example, the control unit 11 determines that the normal condition is not satisfied when the total number of defective nozzles is equal to or greater than a third predetermined number. For example, the control unit 11 determines that the normal condition is not satisfied when there are nozzle rows in which the number of defective nozzles in the nozzle rows is equal to or greater than a fourth predetermined number. When the normal condition is satisfied, the control unit 11 proceeds from the determination of yes in step S150 to step S160. On the other hand, if the normal condition is not satisfied, the process proceeds from the determination of no in step S150 to step S170.

In step S160, the control unit 11 determines that the recording head 15 is in the normal state, and ends the flowchart of fig. 3. That is, the control unit 11 is set to the normal state when it is determined that there is no defective nozzle to the extent that the quality of recording by the recording head 15 is degraded.

On the other hand, in step S170, the control unit 11 determines that the recording head 15 is in an error state, and ends the flowchart of fig. 3. That is, the control unit 11 determines that there is a defective nozzle to the extent that the quality of recording by the recording head 15 is degraded, and sets the state to an error state. When the process proceeds to step S170, the control unit 11 determines that the recording head 15 is in an error state, and may execute processing or display for eliminating a defective nozzle. The process for eliminating the defective nozzles is, for example, so-called flushing of the recording head 15. Further, the display for eliminating the defective nozzle is, for example, a warning display for urging the user to clean the recording head 15 or replace the recording head 15. The control unit 11 causes the display unit 13 to output a warning display.

The order of steps S110, S120 and steps S130, 140 may also be reversed. That is, the control unit 11 may execute steps S130 and S140 after step S100, and execute steps S110 and S120 when the determination in step S140 is "yes".

Note that a configuration in which only one of steps S110 and S120 and steps S130 and 140 is executed is also part of the disclosure implemented in the present embodiment. That is, after step S100, the control unit 11 may shift to steps S150, S160, and S170 as a result of executing steps S110 and S120. Alternatively, after step S100, the control unit 11 may shift to steps S150, S160, and S170 as a result of executing steps S130 and S140.

In addition, step S150 may be omitted. That is, if the control unit 11 determines yes in step S120 or yes in step S140, the process may proceed to step S160 without executing step S150.

4. Second embodiment:

fig. 4 shows an arrangement example of the plurality of nozzles 17 provided in the recording head 15. A description on the premise of the nozzle arrangement in the recording head 15 shown in fig. 4 will also be referred to as a second embodiment. In fig. 4, the recording medium 30 is not shown. With respect to the second embodiment, explanations are omitted for the contents common to the first embodiment.

In the second embodiment, the recording head 15 includes nozzle rows 18c1 and 18c2 each including a plurality of nozzles 17 for ejecting c ink, nozzle rows 18M1 and 18M2 each including a plurality of nozzles 17 for ejecting M ink, nozzle rows 18Y1 and 18Y2 each including a plurality of nozzles 17 for ejecting Y ink, and nozzle rows 18K1 and 18K2 each including a plurality of nozzles 17 for ejecting K ink.

In the second embodiment, the positions of the nozzles 17 in the second direction D2 are the same in every other nozzle row 18c1, 18y1, 18k1, 18m1 of the recording head 15. In the remaining nozzle rows 18m2, 18k2, 18y2, and 18c2 in every other row, the positions of the nozzles 17 are the same in the second direction D2. Therefore, in the second embodiment, the nozzle rows 18c1, 18y1, 18k1, 18m1 are each the first nozzle row, and the nozzle rows 18m2, 18k2, 18y2, 18c2 are each the second nozzle row. In the relationship between the nozzle row 18C1 for ejecting the C ink and the nozzle row 18C2, the nozzle row 18C1 is the first nozzle row, and the nozzle row 18C2 is the second nozzle row.

Similarly, in the relationship between the nozzle row 18M1 for ejecting M ink and the nozzle row 18M2, the nozzle row 18M1 is the first nozzle row, and the nozzle row 18M2 is the second nozzle row. In the relationship between the nozzle row 18Y1 for ejecting the Y ink and the nozzle row 18Y2, the nozzle row 18Y1 is the first nozzle row, and the nozzle row 18Y2 is the second nozzle row. In the relationship between the nozzle row 18K1 for ejecting K ink and the nozzle row 18K2, the nozzle row 18K1 is the first nozzle row, and the nozzle row 18K2 is the second nozzle row.

In the second embodiment, the first nozzle row group is collectively referred to as a first nozzle row group, i.e., the nozzle rows 18c1, 18y1, 18k1, and 18m1, and the second nozzle row group is collectively referred to as a second nozzle row group, i.e., the nozzle rows 18m2, 18k2, 18y2, and 18c 2. The first nozzle array group and the second nozzle array group are arranged so as to be shifted from each other in the nozzle array direction by a distance equal to half of the nozzle pitch NP in the second direction D2.

Fig. 5 is a flowchart showing an error determination process according to the second embodiment, which is executed by the control unit 11 according to the firmware 12. Step S200 is the same as step S100 of the first embodiment. It is understood that steps below step S210 are substantially the same as steps below step S130 of the first embodiment.

In step S210, the control unit 11 refers to the defective nozzle information to determine whether or not the defective nozzle can be complemented by the nozzles 17 in the vicinity. The meaning of the nearby position is as already described.

In the second embodiment, in the relationship between the nozzle row 18c1 and the nozzle row 18c2, the first nozzle with the nozzle number # n and the second nozzle with the nozzle number # n correspond to one nearby nozzle pair, and the first nozzle with the nozzle number # n and the second nozzle with the nozzle number # n +1 correspond to one nearby nozzle pair. Similarly, in terms of the relationship between the nozzle row 18y1 and the nozzle row 18y2, the first nozzle with the nozzle number # n and the second nozzle with the nozzle number # n correspond to one nearby nozzle pair, and the first nozzle with the nozzle number # n and the second nozzle with the nozzle number # n +1 correspond to one nearby nozzle pair.

Similarly, in the relationship between the nozzle row 18m1 and the nozzle row 18m2, the first nozzle with the nozzle number # n and the second nozzle with the nozzle number # n correspond to one nearby nozzle pair, and the first nozzle with the nozzle number # n and the second nozzle with the nozzle number # n +1 correspond to one nearby nozzle pair. Similarly, in the relationship between the nozzle row 18k1 and the nozzle row 18k2, the first nozzle with the nozzle number # n and the second nozzle with the nozzle number # n correspond to one nearby nozzle pair, and the first nozzle with the nozzle number # n and the second nozzle with the nozzle number # n +1 correspond to one nearby nozzle pair.

The control unit 11 refers to the defective nozzle information, and if both of the two nozzles 17 constituting the nearby nozzle pair are defective nozzles, determines that the number of defective nozzles is equal to or greater than a predetermined number with respect to the nearby nozzle pair. On the other hand, if the defective nozzles of the two nozzles 17 constituting the nearby nozzle pair are less than two, it is determined that the number of defective nozzles is less than the predetermined number with respect to the nearby nozzle pair. When the number of defective nozzles is smaller than a predetermined number for all the neighboring nozzle pairs, the control unit 11 determines that the repair can be performed by the nozzles 17 in the neighboring positions. On the other hand, when the number of defective nozzles for at least one of the neighboring nozzle pairs is equal to or greater than the predetermined number, the control unit 11 determines that the completion cannot be performed by the nozzles 17 at the neighboring positions.

In step S220, the control unit 11 branches the process according to the determination result obtained in step S210. When determining that the completion can be performed by the nozzle 17 at the neighboring position, the control unit 11 proceeds from the determination of yes in step S220 to step S230. On the other hand, when it is determined that the completion cannot be performed by the nozzle 17 at the neighboring position, the process proceeds from the determination of no in step S220 to step S250. Steps S230, S240, S250 are the same as steps S150, S160, S170 of the first embodiment. Step S230 may also be omitted.

5. To summarize:

as described above, according to the present embodiment, the recording apparatus 10 includes: a recording head 15 having a plurality of nozzle rows constituted by a plurality of nozzles 17 for ejecting ink of the same color; a detection unit (defective nozzle detection unit 21) that detects a defective nozzle that has become a defective discharge nozzle among the nozzles 17; and a control unit 11 for determining whether or not the recording head 15 is in an error state based on a detection result obtained by the detection unit. The control unit 11 determines that an error state is present when a predetermined number of or more nozzles 17 greater than 1 among the plurality of nozzles 17 in a specific positional relationship in which the recording head 15 can compensate for the mutual ejection are defective nozzles.

According to the above configuration, when the nozzles 17 smaller than the predetermined number of the plurality of nozzles 17 in the recording head 15, which are in the specific positional relationship capable of compensating for the mutual discharge, are defective nozzles, the control unit 11 does not determine that the recording head 15 is in the error state. This makes it possible to avoid a situation in which the recording apparatus determines that recording using the recording head is not possible, even in a situation in which missing dots caused by defective nozzles can be compensated for by normal nozzles and recording is performed. This can improve the work efficiency of the user.

Further, according to the above configuration, the control unit 11 performs the determination based on the detection result obtained by the defective nozzle detecting unit 21. Therefore, it is not necessary to perform recording of the test pattern on the recording medium 30, and it is possible to appropriately determine whether or not the recording head 15 is in an error state by eliminating the burden on the user such as the evaluation work for the test pattern.

Further, according to the present embodiment, the control unit 11 sets the plurality of nozzles 17 belonging to different nozzle rows and located at positions where recording can be performed on the common grid line as the plurality of nozzles 17 in a specific positional relationship.

According to the above configuration, when the nozzles 17 smaller than the predetermined number of the plurality of nozzles 17 for ejecting ink of the same color, which belong to different nozzle rows and are located at positions where recording can be performed on the common raster line, are defective nozzles, the control unit 11 does not determine that the defective nozzles are in an error state.

Further, according to the present embodiment, the recording head 15 includes, as the nozzle rows, a first nozzle row and a second nozzle row which are arranged so that the positions of the nozzles 17 are shifted from each other in the nozzle row direction which is the direction in which the nozzles 17 are arranged. The control unit 11 sets a plurality of nozzles 17 in a specific positional relationship, as a first nozzle which is a nozzle 17 belonging to the first nozzle row and a second nozzle which is a nozzle 17 belonging to the second nozzle row and which is adjacent to the first nozzle and the second nozzle in the nozzle row direction. When both of the first nozzles and the second nozzles adjacent to each other in the nozzle row direction are defective nozzles, it is determined that the nozzle row direction is in an error state.

According to the above configuration, when one nozzle 17 of the neighboring nozzle pair including the two nozzles 17 for ejecting the ink of the same color is a defective nozzle, the control unit 11 does not determine that the nozzle is in the error state.

Further, the present embodiment discloses an error determination method including: a detection step of detecting a defective nozzle that has failed in ejection among the nozzles 17 of the recording head 15 having a plurality of nozzle rows configured of the plurality of nozzles 17 for ejecting ink of the same color; and a determination step of determining whether or not the recording head 15 is in an error state based on a detection result obtained in the detection step. According to the error determination method, in the determination step, when the predetermined number or more of the nozzles 17 in the plurality of nozzles 17 in the specific positional relationship in which the mutual ejection can be complemented by the recording head 15 are defective nozzles, it is determined that the error state is present.

6. Other embodiments:

the present embodiment further includes various modes as described below.

In the description of the first embodiment thus far, in step S130, the control unit 11 extracts the nearby nozzle pairs by limiting them to the combination of the adjacent first nozzle row and second nozzle row. However, the controller 11 may extract the neighboring nozzle pairs from a combination of the first nozzle row and the second nozzle row which are not adjacent to each other, for example, a combination of the nozzle row 18w1 and the nozzle row 18w 4.

The recording apparatus 10 may further include: a recording head 15 (first recording head) provided with a plurality of nozzle rows 18w1, 18w2, 18w3, 18w4, 18w5, 18w6, 18w7, 18w8 shown in fig. 2, and a recording head 15 (second recording head) provided with a plurality of nozzle rows 18c1, 18m1, 18y1, 18k1, 18c2, 18m2, 18y2, 18k2 shown in fig. 4 are provided. That is, the carriage 20 is mounted with a first recording head and a second recording head. For example, on the carriage 20, the first recording head is arranged upstream in the second direction D2 with respect to the second recording head. The control unit 11 performs the error determination process of the first embodiment and the error determination process of the second embodiment, and determines that the recording head is normal when both error determination processes are determined to be normal.

The recording head 15 may be a line head elongated in the first direction D1. That is, the recording head 15 is fixed in the recording apparatus 10 in an orientation rotated by 90 ° from the state shown in fig. 2 or 4. In the case where the recording head 15 is a line head, the carriage 20 is not required. In the line head, each nozzle row is configured by a plurality of nozzles 17 in which the nozzle pitch along the first direction D1 is fixed. Each nozzle row is configured such that a plurality of nozzles 17 are arranged over a range corresponding to the width of the recording medium 30 conveyed in the second direction D2 in the first direction D1. In the configuration in which the recording head 15 is a line head, the "same position" in step S110 means that the positions in the first direction D1 are the same, and the raster lines are lines parallel to the second direction D2.

In the recording head 15, some of the nozzles 17 at both ends of the nozzle row may be set in advance as unused nozzles that are not used in recording. Even if the control unit 11 assumes that a defective nozzle is not used, the defective nozzle is not treated in the error determination process. That is, the control unit 11 performs processing for setting, as a defective nozzle, a nozzle 17 that is not a nozzle not using any nozzle and corresponds to a defective nozzle among the nozzles 17 included in the recording head 15 in the error determination processing.

Description of the symbols

10 … recording device; 11 … a control unit; 12 … firmware; a display part 13 …; 14 … operation receiving part; 15 … recording head; 16 … conveying part; a 17 … nozzle; nozzle rows 18w1, 18w2, 18w3, 18w4, 18w5, 18w6, 18w7, 18w8, 18c1, 18c2, 18m1, 18m2, 18y1, 18y2, 18k1 and 18k2 …; 19 … nozzle face; 20 … a carriage; 21 … a defective nozzle detecting unit; 30 … recording media.