EP4617068A1

EP4617068A1 - Image forming system, cleaning apparatus, inkjet recording apparatus, and storage medium

Info

Publication number: EP4617068A1
Application number: EP25162035.7A
Authority: EP
Inventors: Hajime Kawakami
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 2024-03-11
Filing date: 2025-03-06
Publication date: 2025-09-17
Also published as: JP2025138129A; CN120620859A

Abstract

Disclosed is an image forming system (1), including: an inkjet recording apparatus (10) including an image forming section (13) that includes an inkjet head (132a) to eject ink from a nozzle, and a pretreatment liquid ejection head (133a) to eject a pretreatment liquid to aggregate ink from a nozzle, and that forms an image on a recording medium; a cleaning apparatus (20) including a cleaning member (22a) to clean a nozzle surface of the inkjet head and/or the pretreatment liquid ejection head; and a controller (11). The controller changes a contact portion between the cleaning member and the nozzle surface to an unused position to clean the nozzle surface with the cleaning member.

Description

BACKGROUND OF THE INVENTION

TECHNICAL FIELD

The present invention relates to an image forming system, a cleaning apparatus, an inkjet recording apparatus, and a storage medium.

DESCRIPTION OF RELATED ART

In the related art, there is known an inkjet recording apparatus which is provided with an inkjet head which ejects ink from nozzles and a pretreatment liquid ejection head which ejects a pretreatment liquid which aggregates ink in order to retain the ink on a surface of a recording medium, and which forms an image on the recording medium.
In such an inkjet recording apparatus, when the ink and the pretreatment liquid aggregate on the nozzle surface of the head to form an aggregate, problems such as ejection failure occur. Therefore, a configuration is common in which a predetermined cleaning member is provided and the ink and the mist of the pretreatment liquid adhered to the nozzle surface are cleaned during maintenance.
However, in particular, in the case of an inkjet recording apparatus having a configuration in which an inkjet head and a pretreatment liquid ejection head are mounted on a carriage, the inkjet head and the pretreatment liquid ejection head are disposed close to each other. When the cleaning member is used to clean the nozzle surfaces of the inkjet head and the pretreatment liquid ejection head, the ink and the pretreatment liquid may aggregate on the cleaning member to form aggregates. The cleaning performance of the cleaning member to which the aggregate adheres is reduced.
Although the aggregate formed on the cleaning member can be removed with a strong solvent or the like, this is not preferred because the cleaning member may deteriorate in this case. In addition, in a case where the cleaning member on which the aggregate is formed is replaced each time, it is necessary to stop the operation of the inkjet recording apparatus, which is not preferable because there is a concern that productivity decreases.
Therefore, for example, Pat. No. 6002585 describes a configuration in which the abutting position of the cleaning member on the nozzle surface is changed.

SUMMARY OF THE INVENTION

However, the invention of Patent No. 6002585 is an invention aiming at uniform abrasion of the cleaning member. For this reason, there is a case where a region which is used for cleaning once and to which the aggregate adheres is used again, and thus it is not possible to suppress the deterioration of the cleaning performance of the cleaning member.
The present invention has been made in view of such circumstances. An object of the present invention is to provide an image forming system, a cleaning apparatus, an inkjet recording apparatus, and a storage medium for a program, which are capable of suppressing ejection failure of a head due to cleaning by a cleaning member whose cleaning performance has decreased.
To solve one or more of the problems set forth above, the image forming system according to an aspect of the present invention is an image forming system (1), comprising:

an inkjet recording apparatus (10) including an image forming section (13) that includes an inkjet head (132a) to eject ink from a nozzle, and a pretreatment liquid ejection head (133a) to eject a pretreatment liquid to aggregate ink from a nozzle, and that forms an image on a recording medium;
a cleaning apparatus (20) including a cleaning member (22a) to clean a nozzle surface of the inkjet head and/or the pretreatment liquid ejection head; and
a controller (11), wherein
the controller changes a contact portion between the cleaning member and the nozzle surface to an unused position to clean the nozzle surface with the cleaning member.

Preferably, in the above image forming system, the image forming section includes a carriage (131) on which both the inkjet head and the pretreatment liquid ejection head are mounted.
Preferably, in the above image forming system, in the image forming section, a ratio of a distance (y) between the nozzle of the pretreatment liquid ejection head and the nozzle of the inkjet head closest to the pretreatment liquid ejection head to a distance (x) from the pretreatment liquid ejection head to the recording medium is 4 or more.
Preferably, in the above image forming system, the controller changes the contact portion based on at least one of the number of times of execution of image forming processing, the number of printed sheets, the number of times of maintenance, and an ink ejection amount.
Preferably, the above image forming system includes:

an acquisition section (11) that acquires a cleaning performance of the cleaning member; and
a determination section (11) that determines whether or not the contact portion needs to be changed in accordance with acquired content of the acquisition section, wherein
the controller changes the contact portion in accordance with a determination result of the determination section.

Preferably, in the above image forming system, the acquisition section acquires the cleaning performance of the cleaning member based on presence or absence of movement deficiency when the ink or the pretreatment liquid is ejected from the inkjet head or the pretreatment liquid ejection head.
Preferably, in the above image forming system, the acquisition section acquires the cleaning performance of the cleaning member based on a result of printing of a nozzle deficiency chart and deficiency detection by a laser.
Preferably, the above image forming system includes a measuring section (15) that measures a mist adhesion status on the nozzle surface, wherein
the acquisition section acquires the cleaning performance of the cleaning member based on a measurement result of the measuring section.
Preferably, in the above image forming system, the measuring section measures an amount of mist of the ink adhering to the pretreatment liquid ejection head.
Preferably, the above image forming system includes an operation input section (16) that receives an input of a change instruction for the contact portion,
wherein the acquisition section acquires the cleaning performance of the cleaning member based on input content of the operation input section.
Preferably, in the above image forming system, the acquisition section acquires the cleaning performance of the cleaning member based on a printing condition and an apparatus condition.
Preferably, in the above image forming system, the pretreatment liquid is an aggregating agent, and the ink is a pigment ink that reacts with the pretreatment liquid to aggregate.
Preferably, in the above image forming system, the cleaning member that cleans the nozzle surface of the inkjet head and the cleaning member that cleans the nozzle surface of the pretreatment liquid ejection head are separate bodies.
Preferably, in the above image forming system, the cleaning members which are the separate bodies are different types of cleaning members.
Preferably, in the above image forming system, one of the cleaning members which are the separate bodies is a blade and the other is a wet-type roller.
Preferably, in the above image forming system, the controller changes the contact portion by moving the pretreatment liquid ejection head and the inkjet head, or by moving the cleaning member.
Preferably, in the above image forming system, the controller is capable of individually changing the contact portions of the cleaning members which are the separate bodies.
Preferably, in the above image forming system, the controller changes the contact portion so that the entire surface of the nozzle surface comes into contact with an unused position of the cleaning member.
Preferably, in the above image forming system, the controller changes the contact portions of the different cleaning members to the same direction.
Preferably, in the above image forming system, the controller changes the contact portions of the different cleaning members in opposite directions to each other.
Preferably, the above image forming system includes a notifying section for notifying the necessity of changing the contact portion according to the determination result of the determination section.
A cleaning apparatus according to another aspect of the present invention is a cleaning apparatus (20) for cleaning an inkjet recording apparatus (10) that includes an image forming section (13) that includes an inkjet head (132a) to eject ink from a nozzle, and a pretreatment liquid ejection head (133a) to eject a pretreatment liquid to aggregate ink from a nozzle, and that forms an image on a recording medium, the cleaning apparatus comprising:

a cleaning section (22) including a cleaning member (22a) to clean a nozzle surface of the inkjet head and/or the pretreatment liquid ejection head; and
a controller, wherein
the controller changes a contact portion between the cleaning member and the nozzle surface to an unused position to clean the nozzle surface with the cleaning member.

An inkjet recording apparatus according to another aspect of the present invention is an inkjet recording apparatus (10) comprising:

an image forming section (13) that includes an inkjet head (132a) to eject ink from a nozzle, and a pretreatment liquid ejection head (133a) to eject a pretreatment liquid to aggregate ink from a nozzle, and that forms an image on a recording medium;
a cleaning section (22) that includes a cleaning member (22a) to clean a nozzle surface of the inkjet head and/or the pretreatment liquid ejection head; and
a controller (11), wherein
the controller changes a contact portion between the cleaning member and the nozzle surface to an unused position to clean the nozzle surface with the cleaning member.

A storage medium according to another aspect of the present invention is a non-transitory storage medium storing a computer readable program for a computer of an inkjet recording apparatus (10) including: an image forming section (13) that includes an inkjet head (132a) to eject ink from a nozzle, and a pretreatment liquid ejection head (133a) to eject a pretreatment liquid to aggregate ink from a nozzle, and that forms an image on a recording medium; and a cleaning section (22) that includes a cleaning member (22a) to clean a nozzle surface of the inkjet head and/or the pretreatment liquid ejection head, the program causing the computer to perform
changing a contact portion between the cleaning member and the nozzle surface to an unused position to clean the nozzle surface with the cleaning member.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages and features provided by one or more embodiments of the invention will become more fully understood from the detailed description given hereinafter and the appended drawings which are given by way of illustration only, and thus are not intended as a definition of the limits of the present invention, and wherein:

Fig. 1 is a block diagram of the image forming system of the first embodiment;
Fig. 2 is a schematic configurational view of an inkjet recording apparatus;
FIG. 3 is a schematic front view of the image forming section;
Fig. 4A is a schematic front view of a cleaning section;
Fig. 4B is a schematic front view of a cleaning section having a configuration of modification example 1;
Fig. 4C is a schematic front view showing a cleaning section having a configuration of modification example 2;
Fig. 4D is a schematic front view showing a cleaning section having a configuration of modification example 3;
Fig. 5 is a schematic front view illustrating movement of the cleaning members in contact portion change process; and
Fig. 6 is a block diagram of an image forming apparatus of a second embodiment.

DETAILED DESCRIPTION

Hereinafter, one or more embodiments of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the disclosed embodiments.
An embodiment of the present invention will be described below with reference to the drawings. Note that the following description is an example of one embodiment of the present invention, and does not limit the present invention.

(first embodiment)

Fig. 1 is a block diagram of an image forming system 1 of the first embodiment. Fig. 2 is a perspective view of the inkjet recording apparatus 10. The image forming system 1 includes an inkjet recording apparatus 10 and a cleaning apparatus 20. Furthermore, the inkjet recording apparatus 10 includes a controller 11, a conveyance section 12, an image forming section 13, a notifying section 14, a measuring section 15, and an operation input section 16.
Note that hereinafter, an X direction, a Y direction, and a Z direction are directions illustrated in Fig. 2. Further, in the description below, the X direction, the Y direction, and the Z direction correspond to a width direction, a conveyance direction, and a height direction, respectively.

(controller)

The controller 11 includes a central processing unit (CPU), a random access memory (RAM), and a read only memory (ROM). The controller 11 controls the overall operation of the inkjet recording apparatus 10.
The CPU controls each part of the inkjet recording apparatus 10. The RAM is a volatile memory that temporarily stores various kinds of information in a writable and readable manner. The ROM is a non-volatile memory in which various types of information and programs are stored in a readable manner. More specifically, the controller 11 reads a designated program from various programs stored in the ROM and develops the program in the RAM by the CPU. Next, the controller 11 performs various kinds of processing in cooperation with the loaded program.

(Conveyance section)

As illustrated in Fig. 2, the conveyance section 12 includes two conveyance rollers 12a and 12b that rotate in a conveyance direction around rotary shafts extending in a width direction. Furthermore, the conveyance section 12 includes a ring-shaped conveyance belt 12c.
The inner side of the conveyance belt 12c is supported by the conveyance rollers 12a and 12b. The recording media M are placed on the conveyance surface of the conveyance belt 12c. Then, the conveyance rollers 12a and 12b rotate and circulate in the conveyance direction in accordance with operation of a conveyance motor for the rollers. As a result, the conveyance belt 12c conveys the recording media M in the conveyance direction.
In addition, it is preferable that a predetermined adhesive is applied to a mounting surface which is a surface different from an inner surface which comes into contact with the conveyance rollers 12a and 12b and is an outer surface on a side on which the recording media M are mounted, in the conveyance belt 12c. With this configuration, the recording medium M can be prevented from being misaligned.
The recording medium M is, for example, cloth cut to a constant size. The recording media M are supplied onto the conveyance belt 12c by a media supplying section (not shown). The recording medium M on which the image is recorded by the ink ejection of the image forming section 13 is discharged to a predetermined discharge section. Note that the recording medium M is not limited to fabric. The recording medium M may be any recording medium on which landed ink can be fixed, and may be any of various media such as paper.

(Image Forming Section)

The image forming section 13 forms an image by ejecting color ink onto the recording medium M conveyed by the conveyance section 12 at an appropriate timing based on image data acquired from an external apparatus or the like. The image forming section 13 includes a carriage 131, an ink ejection section 132, and a pretreatment liquid ejection section 133.

{Carriage}

The carriage 131 includes, for example, a belt or the like stretched between two pulleys that are rotated by a motor (not illustrated). An ink ejection section 132 and a pretreatment liquid ejection section 133 are mounted on the carriage 131. The carriage 131 causes the ink ejection section 132 and the pretreatment liquid ejection section 133 to scan in the width direction by the rotation operation of the motor based on the driving signal output by the controller 11.
In addition, the inkjet recording apparatus 10 according to the present embodiment is a serial head type which forms an image by discharging ink from the ink ejection section 132 onto the recording medium M while scanning the carriage 131 in the width direction. Note that the image may be formed by scanning the carriage 131 once, or the image may be formed by scanning the carriage 131 a plurality of times.
In addition, the inkjet recording apparatus 10 according to the present embodiment is of an in-line type. That is, the image forming section 13 performs image formation by the ink ejection of the ink ejection section 132 continuously with the pretreatment by the ejection of the pretreatment liquid of the pretreatment liquid ejection section 133.

{ink ejection section}

Fig. 3 is a schematic front view of a cross section of the carriages 131 as viewed from the conveyance direction. The ink ejection section 132 includes a plurality of inkjet heads 132a that eject color inks of respective colors, for example, C (cyan), M (magenta), Y (yellow), and K (black). The inkjet heads 132a each include color ink tanks, channels, piezoelectric elements, and a plurality of nozzles. As illustrated in Fig. 3, the inkjet heads 132a are mounted in the width direction in the carriage 131. Under the control of the controller 11, the inkjet heads 132a eject the color inks onto the recording media M by causing the piezoelectric elements to apply pressure-fluctuations to the color inks supplied from the tanks to the nozzles via the channels.
Note that the color ink ejected by the ink ejection section 132 is, for example, pigment ink. The pigment ink is an ink containing a pigment, resin particles (binder resin), and water. In an image formed with pigment ink, pigment particles are likely to be exposed in the vicinity of the image forming surface of the recording medium M. Therefore, an image formed with the pigment ink exhibits high color developability.

{pretreatment liquid ejection section}

The pretreatment liquid ejection section 133 includes a pretreatment liquid ejection head 133a provided at one end in a width direction of the carriage 131. The pretreatment liquid ejection head 133a is provided outside the ink ejection section 132. In addition, the pretreatment liquid ejection head 133a includes a tank of the pretreatment liquid, a channel, piezoelectric elements, a plurality of nozzles, and the like, similarly to the inkjet head 132a. Then, the pretreatment liquid ejection head 133a ejects the pretreatment liquid under the control of the controller 11.
Specifically, the pretreatment liquid ejected by the pretreatment liquid ejection head 133a is, for example, pretreatment ink containing an aggregating agent. The pretreatment ink is mixed in a liquid state with the color ink ejected by the inkjet head 132a. The pretreatment ink contains at least an aggregating agent, and may contain other components such as a solvent, a surfactant, or water. The aggregating agent contained in the pretreatment ink is not particularly limited as long as it generates an aggregate upon contact with the color ink, and is, for example, a polyvalent metal salt, an organic acid, or an inorganic acid.
In addition, the pretreatment liquid ejection head 133a ejects the pretreatment liquid when the carriage 131 scans from the other end where the ink ejection section 132 is provided to the one end where the pretreatment liquid ejection section 133 is provided. According to the above-described configuration, the pretreatment and the image formation can be simultaneously performed by one scanning of the carriage 131, and the productivity can be increased.
Furthermore, as illustrated in Fig. 3, the length from the nozzle surface of the pretreatment liquid ejection head 133a to the recording medium M is defined as x [mm]. The length between the nozzle of the pretreatment liquid ejection head 133a and the nozzle of the nearest inkjet head 132a is represented by y [mm]. At this time, the image forming section 13 according to the present embodiment is configured such that the ratio of y to x (i.e., y/x) is 4 or more, and more preferably 10 or more. In other words, it is preferable that while the distance between the nozzle surface and the recording medium M is reduced, the distance between the head that ejects one of the liquid droplets and the head that ejects the other liquid droplet is increased. Such an arrangement can reduce the possibility that mist of the other liquid adheres to and aggregates on the nozzle surface of the head that ejects the one liquid. Furthermore, since the number of aggregates formed on the nozzle surface can be reduced, the aggregates can be easily removed by the cleaning member 22a described later.

(Notifying Section)

The notifying section 14 notifies various kinds of information under the control of the controller 11. The notifying section 14 is, for example, a display part having a screen, a speaker that produces sound, or a communication section that can communicate with another apparatus via a predetermined network.

(measuring section)

The measuring section 15 includes a line sensor having, for example, a CCD sensor or a CMOS sensor. The measuring section 15 one dimensionally images the nozzle surfaces of the inkjet head 132a and the pretreatment liquid ejection head 133a at appropriate timings. The measuring section 15 can perform imaging in each of the RGB wavelength bands, for example. The measuring section 15 transmits image data acquired by imaging to the controller 11.

(Operation Input Section)

The operation input section 16 includes, for example, various operation keys. The operation input section 16 converts a user's input operation into an operation signal, and outputs the operation signal to the controller 11. Note that when the notifying section 14 is a display part, the operation input section 16 may be a touch screen.

(cleaning apparatus)

Referring back to Fig. 1, the cleaning apparatus 20 is an apparatus that cleans an inkjet head 132a and/or a pretreatment liquid ejection head 133a. More specifically, the cleaning apparatus 20 cleans a nozzle surface, which is a lower face of the inkjet head 132a and the pretreatment liquid ejection head 133a and in which nozzles to eject ink or pretreatment liquid are provided. The cleaning apparatus 20 includes a controller 21, a cleaning section 22, and a drive section 23.

{controller}

The controller 21 includes a central processing unit (CPU), a random access memory (RAM), and a read only memory (ROM). The controller 21 controls the overall operation of the cleaning apparatus 20 according to a signal received from the controller 11 of the inkjet recording apparatus 10.

{cleaning section}

The cleaning section 22 includes cleaning members 22a (see Fig. 4A and the like), and cleans the nozzle surface. The cleaning member 22a is, for example, a blade, a wet roller, or a web. In the following description, as illustrated in FIG. 4A, a configuration in which the cleaning section 22 includes a plurality of (five in the present embodiment) cleaning members 22a respectively corresponding to the inkjet heads 132a and the pretreatment liquid ejection head 133a is exemplified, but the invention is not limited thereto.

< Modification examples 1-3 >

For example, as illustrated in Fig. 4B, the cleaning section 22 may be configured to clean the nozzle surfaces of all the inkjet heads 132a and the pretreatment liquid ejection head 133a with one cleaning member 22a. Furthermore, as illustrated in Fig. 4C, a configuration may be adopted in which the cleaning section 22 includes a cleaning member 22a for cleaning the nozzle surfaces of the plurality of inkjet heads 132a and a cleaning member 22a for cleaning the nozzle surface of the pretreatment liquid ejection head 133a separately. Further, in the above-described configuration, as shown in FIG. 4D, the cleaning member 22a for cleaning the nozzle surfaces of the plurality of inkjet heads 132a may be a wet roller, and the cleaning member 22a for cleaning the pretreatment liquid ejection head 133a may be a blade. Thus, the separate cleaning members 22a, 22a may be of different types.

{Drive Section}

When the cleaning section 22 cleans the nozzle surface, the drive section 23 moves the cleaning member 22a so as to be in contact with the nozzle surface. In addition, the drive section 23 executes a contact portion change process of changing the contact portion between the cleaning member 22a and the nozzle surface to an unused position by moving the cleaning member 22a according to a signal received from the controller 11.

[Execution Timing of contact portion change process]

The timing at which the controller 11 executes the contact portion change process can be set as appropriate. For example, the controller 11 executes the contact portion change process when a predetermined condition in which a reduction in the cleaning performance of the cleaning member 22a is assumed is satisfied. The predetermined condition is, for example, that the number of times of execution of the image forming processing exceeds a predetermined number of times. Alternatively, the number of printed sheets exceeds a predetermined value. Alternatively, the number of times of maintenance exceeds a predetermined number of times. Alternatively, the ink ejection amount exceeds a predetermined value.
Alternatively, the controller 11 acquires the cleaning performance of the cleaning member 22a and executes the contact portion change process in accordance with the acquired result. In the above-described configuration, the controller 11 functions as an acquisition section that acquires the cleaning performance of the cleaning member 22a. Furthermore, the controller 11 functions as a determination section that determines whether it is necessary to change the contact portion in accordance with the acquired cleaning performance of the cleaning member 22a.
In detail, for example, the controller 11 causes the ink or the pretreatment liquid to be ejected from the inkjet head 132a or the pretreatment liquid ejection head 133a after the printing is finished. Then, when there is a movement deficiency as a result of the ejection, contact portion change process is executed.
More specifically, the controller 11 causes the inkjet head 132a or the pretreatment liquid ejection head 133a to print a nozzle deficiency chart at least twice. Then, in a case where the nozzle deficiency disappears for the second time from the place where the nozzle deficiency occurred for the first time and the nozzle deficiency occurs for the second time in the place where the nozzle deficiency did not occur for the first time, the controller 11 determines that there is a movement deficiency. The presence or absence of movement deficiency can be detected by, for example, laser deficiency detection. In a case where the aggregate adheres to the cleaning member 22a and the cleaning performance is deteriorated, such a movement deficiency is likely to occur. Therefore, when there is a movement deficiency, the controller 11 executes the contact portion change process.
Alternatively, the controller 11 executes contact portion change process on the basis of a measurement result of the measuring section 15. Specifically, the controller 11 acquires the image data of the nozzle surface of the pretreatment liquid ejection head 133a from the measuring section 15 after the image formation. The controller 11 measures the adhesion status of ink mist on the nozzle surface by binarizing the acquired image data. In a case where ink mist is adhered to a predetermined ratio or more of the nozzle surface of the pretreatment liquid ejection head 133a, it is considered that aggregates are adhered to the cleaning member 22a and the cleaning performance is degraded. Therefore, the controller 11 changes the contact portion.
Alternatively, the controller 11 executes the contact portion change process in a case where the printing condition or the apparatus condition satisfies a predetermined condition in which deterioration of the cleaning performance of the cleaning member 22a is assumed. The predetermined condition related to the printing condition is, for example, a case where the coverage is equal to or more than a predetermined value. Alternatively, it is a case where the application amount of the pretreatment liquid is larger than usual. Alternatively, it is a case where the number of continuously printed sheets/distance exceeds a predetermined value. Alternatively, it is a case where the head gap becomes larger than a predetermined value (i.e., a case where the recording medium M is a predetermined fabric type). The predetermined condition related to the apparatus condition is, for example, a case where the carriage 131 does not include a mist catcher.
Alternatively, the controller 11 executes the contact portion change process in response to an input operation on the operation input section 16 by a user who has viewed the adhesion status of the aggregation substances on the cleaning member 22a. Alternatively, the controller 11 executes the contact portion change process periodically, for example, every three months.
Note that the above-described configuration related to the execution timing of the contact portion change process is not limited to employment of either one alone, but a plurality of configurations may be employed in combination. For example, the controller 11 executes the contact portion change process when a predetermined condition is satisfied or when image formation is performed under predetermined printing conditions.

[contact portion change process]

In the contact portion change process, as illustrated in Fig. 5, the controller 11 causes the drive section 23 to move the cleaning member 22a, thereby changing the contact portion to the unused position. At the time of the movement, the cleaning member 22a is moved by at least the width of the nozzle surface or more so that the entire surface of the nozzle surface comes into contact with the cleaning member 22a. With this structure, the entire nozzle surface can be cleaned with the cleaning member 22a having no foreign substance adhered thereto.
In a case where the influence of the adhesion of the aggregation substance is detected even when the contact portion change process is executed, it is preferable to execute the contact portion change process again. Furthermore, in a case where the entire surface of the cleaning member 22a is used as the contact portion and the contact portion cannot be changed to an unused position, it is preferable that the notifying section 14 provides a notification prompting the user to perform maintenance or replace the cleaning member 22a.
Note that Fig. 5 illustrates a configuration in which the contact portions of both the cleaning member 22a corresponding to the inkjet head 132a and the cleaning member 22a corresponding to the pretreatment liquid ejection head 133a are changed, but the present invention is not limited thereto. For example, in a case where the controller 11 can individually control each of the plurality of cleaning members 22a and only one cleaning member 22a needs to execute the contact portion change process, the contact portions of the other cleaning members 22a may not be changed.
Fig. 5 illustrates a configuration in which the cleaning member 22a corresponding to the inkjet head 132a and the cleaning member 22a corresponding to the pretreatment liquid ejection head 133a are moved in opposite directions. In the case of the above-described configuration, it is possible to reduce the risk of aggregation of the ink and the pretreatment agent due to the proximity of the cleaning members 22a, 22a. On the other hand, without being limited to the above-described configuration, a configuration may be adopted in which the cleaning members 22a and 22a are moved in the same direction. In the case of the above-described configuration, both cleaning members 22a can be operated in conjunction with each other, and the control can be simplified.
Further, in the above description, the contact portion is changed by moving the cleaning member 22a by the drive section 23, but the present invention is not limited thereto. That is, the controller 11 may change the contact portion with the cleaning member 22a by changing the movement position of the carriage 131 in the cleaning maintenance.

[Examples]

Next, with respect to Examples and Comparative Examples of the present invention, the results of evaluating preferred configurations by various tests will be described. Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto.

[Test 1. Case where Change Timing is Periodic]

The controller 11 was set so that the image forming system 1 including the image forming section 13 as illustrated in Fig. 3 and the cleaning member 22a as illustrated in Fig. 4D operated as in the following Example 1 and Comparative Examples 1-2. Note that the cleaning member 22a to clean the inkjet head 132a is a wet roller. The cleaning member 22a to clean the pretreatment liquid ejection head 133a is a blade.

(Example 1)

The contact portion change process is executed each time cleaning maintenance of the nozzle surface is performed 300 times.

(Comparative Example 1)

To change a contact portion every time cleaning maintenance is performed. Note that the cleaning member 22a has six usable portions as contact portions, which are sequentially changed. That is, in Comparative Example 1, the region which has been used as the contact portion is reused after the sixth cleaning maintenance.

(Comparative Example 2)

The contact portion is not changed.
Note that in Test 1 and Tests 2 and 3 to be described later, the contact portion is changed by moving the carriage 131.
For the image forming systems 1 of Example 1 and Comparative Examples 1-2, in a case where an aggregate was caused to adhere to the cleaning member 22a in the predetermined-number-th cleaning maintenance, the cleaning performance of the cleaning member 22a immediately after each cleaning maintenance was evaluated. The test result was evaluated as G (Good) in a case where sufficient cleaning performance was exhibited and as NG (Not Good) in a case where cleaning failure occurred.
Table I shows the results of the case where the aggregate was caused to adhere to the cleaning member 22a in the 300th cleaning maintenance. Table II shows the results in the case where the aggregate was caused to adhere to the cleaning member 22a in the 298th cleaning maintenance.
As illustrated in Table I, in the configuration of Comparative Example 1, the adhesion place is used again as the contact portion every six times of cleaning maintenance since the adhesion of the aggregate to the cleaning member 22a. Furthermore, in the configuration of Comparative Example 2, after the aggregate adheres to the cleaning member 22a, the adhesion place is used as the contact portion. Therefore, with the configurations of Comparative Examples 1-2, the cleaning performance of the cleaning member 22a cannot be ensured.
On the other hand, in the case of the configuration of Example 1, unlike the configurations of Comparative Examples 1 and 2, the contact portion change process is executed after the aggregate adheres to the cleaning member 22a. Therefore, as indicated in Table I, the cleaning performance of the cleaning member 22a can be ensured.
Provided that, as in the example of Table II, even with the configuration of Example 1, the nozzle surface is cleaned by the cleaning member 22a whose cleaning performance has been reduced when the execution timings of the contact portion change process do not match. Therefore, it is preferable to combine a configuration in which the contact portion is changed to the unused position when a decrease in the cleaning performance of the cleaning member 22a is detected.

[Test 2. Case of Detecting Change Timing]

The controller 11 was set so that the image forming system 1 including the image forming section 13 as illustrated in Fig. 3 and the cleaning member 22a as illustrated in Fig. 4D operated as in the following Example 2.

(Example 2)

The presence or absence of movement deficiency is confirmed by laser deficiency detection immediately after cleaning of the nozzle surface, and contact portion change process is executed in a case where movement deficiency is confirmed.
In the image forming systems 1 of Example 2 and Comparative Examples 1-2, unrepairable aggregates were caused to adhere to the cleaning member 22a during the cleaning maintenance, and the cleaning performances of the cleaning member 22a in the cleaning maintenance before and after the cleaning maintenance were evaluated. The test result was rated G when sufficient cleaning performance was exhibited and rated NG when cleaning failure occurred.
The results of Test 2 are shown in Table III.

[Table 3]

In the configurations of Comparative Examples 1 and 2, as in Test 1, even when an aggregate adheres to the cleaning member 22a, the adhesion site is used again as a contact portion. Therefore, the cleaning performance of the cleaning member 22a cannot be ensured. On the other hand, in the configuration of the Example 2, even when the aggregate adheres to the cleaning member 22a, the contact portion change process is executed by confirming the movement deficiency. Therefore, as illustrated in Table III, the configuration of Example 2 can always secure the cleaning performance of the cleaning member 22a.

[Test 3. Case of Predicting Change Timing]

The controller 11 was set so that the image forming system 1 including the image forming section 13 as illustrated in Fig. 3 and the cleaning member 22a as illustrated in Fig. 4D operated as in the following Example 3.

(Example 3)

The contact portion change process is executed after cleaning maintenance after image formation under a printing condition where a head gap exceeds 3 mm.
In the image forming systems 1 of Example 3 and Comparative Examples 1-2, the image formation under the printing condition in which the head 3 mm becomes a 5 mm, the cleaning maintenance, the image formation under the printing condition in which the head gap becomes a gap, the cleaning maintenance, the image formation, and the cleaning maintenance are performed in this order. Furthermore, an aggregate was caused to adhere to the cleaning member 22a during image formation under printing conditions that resulted in a head gap of 5 mm. Then, the cleaning performance of the cleaning member 22a after the cleaning maintenance was evaluated. The test result was rated G when sufficient cleaning performance was exhibited and rated NG when cleaning failure occurred.
The results of Test 3 are set forth in Table IV

[Table 4]

In the configurations of Comparative Examples 1 and 2, as in Tests 1 and 2, even when an aggregate adheres to the cleaning member 22a, the adhesion site is used again as a contact portion. Therefore, the cleaning performance of the cleaning member 22a cannot be ensured. On the other hand, in the configuration of Example 3, when image formation is performed under printing conditions in which the head gap exceeds 3 mm, that is, after image formation under printing conditions in which aggregates tend to adhere to the cleaning member 22a, the contact portion is changed to the unused position. Therefore, as indicated in Table IV, the configuration of Example 3 can secure the cleaning performance of the cleaning member 22a.

(summary)

In the foregoing, it has been described that the configurations of Examples 1 to 3 all can secure the cleaning performance of the cleaning member 22a, but the configurations of Examples 1 to 3 have different features.
For example, in the configuration of Example 1, the contact portion is periodically changed to the unused position in accordance with the number of times of cleaning maintenance. Therefore, the simplest control system can be adopted as compared with other configurations, and the downtime does not increase. On the other hand, as described above, in a case where the aggregation substances are irregularly adhered, it is likely that the cleaning performance of the cleaning member 22a cannot be ensured.
Furthermore, the configuration according to the Example 2 determines the timing of changing the contact portion by performing deficiency detection using a laser. Therefore, the contact portion can be changed to the unused position at an appropriate timing, and the cleaning member 22a can be used up without waste. On the other hand, since a detection means such as a laser is required, the cost increases. Further, since the deficiency detection is performed after the cleaning maintenance, the downtime increases.
Furthermore, in the configuration of Example 3, the contact portion is changed to the unused position and the detection operation is not performed when image formation is performed under printing conditions that aggregate is likely to adhere to the cleaning member 22a. Therefore, the downtime does not increase. Furthermore, although not as much as in Example 2, the contact portion is easily changed at accurate timing.
Therefore, among the configurations of Examples 1 to 3, the configuration of Example 3 is most preferable, but it is preferable that the user grasps the characteristics of each configuration and then selects which configuration to adopt as necessary.

[Effects of Embodiment]

As described above, the controller 11 of the image forming system 1 according to the present embodiment changes the contact portion between the cleaning member 22a and the nozzle surface to the unused position and cleans the nozzle surface with the cleaning member 22a. According to the configuration, it is possible to suppress ejection failure of the inkjet head 132a and the treatment liquid ejection head 133a due to cleaning by the cleaning member 22a whose cleaning ability has decreased.
Furthermore, in a case where the cleaning member 22a is a blade, when the cleaning member 22a is replaced with a completely new blade, bounding may occur. On the other hand, ink mist is likely to wet and spread particularly on the slightly worn cleaning member 22a. Therefore, when only the contact portion is changed without replacing the cleaning member 22a to which the aggregate adheres, the cleaning performance is likely to be maintained. Furthermore, it is possible to suppress the occurrence of downtime related to the replacement of the cleaning member 22a.
In addition, as a configuration for suppressing adhesion of mist, a mist catcher that aspirates mist by air is known. However, even if a mist catcher is provided on the carriage 131, it is not possible to completely prevent adhesion of mist to the nozzle surface. In addition, since the carriage 131 usually has a weight limit or the like, it is not preferable to provide the mist catcher. On the other hand, according to the above configuration, ejection failure of the inkjet head 132a and the pretreatment liquid ejection head 133a due to adhesion and aggregation of mist can be suppressed without providing a mist catcher.

[Other Configurations]

Although the present invention has been described in detail based on the embodiment, the present invention is not limited to the above-described embodiment. Of course, various modifications are possible within the scope of the invention described in the claims and their equivalents.
Although it has been described above that the contact portion is changed in accordance with the determination result of the controller 11 which is the determination section, it is not limited thereto. For example, the notifying section 14 may notify the user before the execution of the contact portion change process. Then, in a case where the user instructs the change of the contact portion by the operation of the operation input section 16, the contact portion change process may be executed. Note that in the above-described configuration, if the user does not give an instruction to perform the contact portion change process, the controller 11 preferably causes the notifying section 14 to provide notification to the user to recommend, for example, confirmation of the cleaning member 22a or replacement of the cleaning member.
Furthermore, although the configuration in which the image data of the nozzle surface of the pretreatment liquid ejection head 133a is acquired by the measuring section 15 and the contact portion change process is executed according to the adhesion status of ink mist has been described above, it is not limited thereto. That is, as a configuration in which the image data of the nozzle surface of the inkjet head 132a is acquired by the measuring section 15, a configuration may be adopted in which the contact portion change process is executed in accordance with the adhesion status of the pretreatment liquid mist. Provided that the ink has a color, whereas the pretreatment liquid is transparent. Therefore, it is easy and preferable to determine whether or not mist adheres to a predetermined percentage or more of the nozzle surface based on the image of the nozzle surface of the pretreatment liquid ejection head 133a.
In addition, in the above description, a case where the inkjet recording apparatus 10 includes the carriage 131 is exemplified, but the invention is not limited thereto. Even in a configuration in which the inkjet head 132a and the pretreatment liquid ejection head 133a are not mounted on one carriage 131 and are not close to each other, for example, mist of one liquid may adhere to a nozzle surface of a head that ejects the other liquid via the recording media M. Therefore, the present invention is also applicable to a case where the inkjet recording apparatus 10 is of a line head type that does not include the carriage 131 and ejects droplets from, for example, the inkjet head 132a and the pretreatment liquid ejection head 133a arranged in the conveyance direction onto the recording media M being conveyed.
In addition, in the above description, a configuration in which the inkjet recording apparatus 10 includes the controller 11 is exemplified, but the invention is not limited thereto. That is, the controller 11 may be included in an apparatus separate from the inkjet recording apparatus 10. In addition, in the above description, a configuration in which the inkjet recording apparatus 10 and the cleaning apparatus 20 are separate apparatuses has been exemplified, but the invention is not limited thereto. That is, as shown in FIG. 6, the inkjet recording apparatus 10 of the second embodiment may be configured to include the cleaning section 22 and the drive section 23 controlled by the controller 11.
In the above description, an example in which a hard disk, a semiconductor non-volatile memory, or the like is used as a computer-readable medium for the program according to the present invention has been disclosed, but the medium is not limited to this example. As another computer-readable medium, a portable recording medium such as a CD-ROM can be applied. Furthermore, a carrier wave is also applied as a medium for providing data of the program according to the present invention via a communication line.
According to the present embodiment, it is possible to suppress ejection failure of the head due to cleaning by the cleaning member whose cleaning performance has decreased.
Although embodiments of the present invention have been described and illustrated in detail, the disclosed embodiments are made for purposes of illustration and example only and not limitation. The scope of the present invention should be interpreted by terms of the appended claims.

Claims

An image forming system (1), comprising:
an inkjet recording apparatus (10) including an image forming section (13) that includes an inkjet head (132a) to eject ink from a nozzle, and a pretreatment liquid ejection head (133a) to eject a pretreatment liquid to aggregate ink from a nozzle, and that forms an image on a recording medium;

a cleaning apparatus (20) including a cleaning member (22a) to clean a nozzle surface of the inkjet head and/or the pretreatment liquid ejection head; and

a controller (11), wherein

the controller changes a contact portion between the cleaning member and the nozzle surface to an unused position to clean the nozzle surface with the cleaning member.
The image forming system according to claim 1, wherein
the image forming section includes a carriage (131) on which both the inkjet head and the pretreatment liquid ejection head are mounted.
The image forming system according to claim 1, wherein
in the image forming section, a ratio of a distance (y) between the nozzle of the pretreatment liquid ejection head and the nozzle of the inkjet head closest to the pretreatment liquid ejection head to a distance (x) from the pretreatment liquid ejection head to the recording medium is 4 or more.
The image forming system according to claim 1, wherein the controller changes the contact portion based on at least one of the number of times of execution of image forming processing, the number of printed sheets, the number of times of maintenance, and an ink ejection amount.
The image forming system according to claim 1, comprising:
an acquisition section (11) that acquires a cleaning performance of the cleaning member; and

a determination section (11) that determines whether or not the contact portion needs to be changed in accordance with acquired content of the acquisition section, wherein

the controller changes the contact portion in accordance with a determination result of the determination section.
The image forming system according to claim 5, wherein the acquisition section acquires the cleaning performance of the cleaning member based on presence or absence of movement deficiency when the ink or the pretreatment liquid is ejected from the inkjet head or the pretreatment liquid ejection head.
The image forming system according to claim 6, wherein the acquisition section acquires the cleaning performance of the cleaning member based on a result of printing of a nozzle deficiency chart and deficiency detection by a laser.
The image forming system according to claim 5, comprising a measuring section (15) that measures a mist adhesion status on the nozzle surface, wherein
the acquisition section acquires the cleaning performance of the cleaning member based on a measurement result of the measuring section.
The image forming system according to claim 8, wherein the measuring section measures an amount of mist of the ink adhering to the pretreatment liquid ejection head.
The image forming system according to claim 5, comprising an operation input section (16) that receives an input of a change instruction for the contact portion,
wherein the acquisition section acquires the cleaning performance of the cleaning member based on input content of the operation input section.
The image forming system according to claim 5, wherein the acquisition section acquires the cleaning performance of the cleaning member based on a printing condition and an apparatus condition.
The image forming system according to any one of claims 1 to 11, wherein
the pretreatment liquid is an aggregating agent, and
the ink is a pigment ink that reacts with the pretreatment liquid to aggregate.
A cleaning apparatus (20) for cleaning an inkjet recording apparatus (10) that includes an image forming section (13) that includes an inkjet head (132a) to eject ink from a nozzle, and a pretreatment liquid ejection head (133a) to eject a pretreatment liquid to aggregate ink from a nozzle, and that forms an image on a recording medium, the cleaning apparatus comprising:
a cleaning section (22) including a cleaning member (22a) to clean a nozzle surface of the inkjet head and/or the pretreatment liquid ejection head; and

a controller, wherein

the controller changes a contact portion between the cleaning member and the nozzle surface to an unused position to clean the nozzle surface with the cleaning member.
An inkjet recording apparatus (10) comprising:
an image forming section (13) that includes an inkjet head (132a) to eject ink from a nozzle, and a pretreatment liquid ejection head (133a) to eject a pretreatment liquid to aggregate ink from a nozzle, and that forms an image on a recording medium;

a cleaning section (22) that includes a cleaning member (22a) to clean a nozzle surface of the inkjet head and/or the pretreatment liquid ejection head; and

a controller (11), wherein

the controller changes a contact portion between the cleaning member and the nozzle surface to an unused position to clean the nozzle surface with the cleaning member.
A non-transitory storage medium storing a computer readable program for a computer of an inkjet recording apparatus (10) including: an image forming section (13) that includes an inkjet head (132a) to eject ink from a nozzle, and a pretreatment liquid ejection head (133a) to eject a pretreatment liquid to aggregate ink from a nozzle, and that forms an image on a recording medium; and a cleaning section (22) that includes a cleaning member (22a) to clean a nozzle surface of the inkjet head and/or the pretreatment liquid ejection head, the program causing the computer to perform
changing a contact portion between the cleaning member and the nozzle surface to an unused position to clean the nozzle surface with the cleaning member.