JP7388094B2 - Inkjet head maintenance device, inkjet recording device, and inkjet head maintenance method - Google Patents

Description

The present invention relates to an inkjet head maintenance apparatus, an inkjet recording apparatus, and an inkjet head maintenance method.

2. Description of the Related Art Conventionally, there is an inkjet recording apparatus that records an image by ejecting ink from a nozzle of an inkjet head and causing the ink to land on a desired position on a recording medium. If ink adheres to the ink ejection surface of the ink ejection head (the nozzle opening surface where the nozzle opening is formed), this ink may drip onto the recording medium and stain the recording medium, or the adhered ink may stain the nozzle opening. If a portion of the ink is blocked, the ink may solidify and cause ink ejection failure. For this reason, ink jet recording apparatuses use a maintenance method in which the ink ejection surface of the ink ejection head is cleaned by wiping it with a wiping member impregnated with a cleaning liquid.

For example, Patent Document 1 discloses a maintenance method in which ink is scraped off an ink ejection surface with a blade, and a cylindrical cleaning roller serving as a wiping member is rotated and pressed against the ink ejection surface to wipe the ink. In the method described in Cited Document 1, a part of the wiping member is immersed in a reservoir filled with the cleaning liquid to impregnate the wiping member with the cleaning liquid, and the cleaning liquid impregnated in the wiping member is squeezed out by a regulating plate, thereby discharging the cleaning liquid in the wiping member. The ink ejection surface is wiped while adjusting the amount of impregnation.

Japanese Patent Application Publication No. 2008-179125

However, the wiping member takes in air when it restores its shape after the cleaning liquid is squeezed out, so when the cleaning liquid is squeezed out from the wiping member again, the air is discharged together with the cleaning liquid, causing bubbles in the cleaning liquid. For this reason, the bubbles of the cleaning liquid squeezed out from the wiping member end up staying in the cleaning liquid storage section. If these bubbles adhere to the ink ejection surface directly or via a wiping member, this will lead to ink ejection failure. Therefore, with the above-mentioned conventional technology, there is a problem that maintenance may not be performed properly due to the foam of the cleaning liquid.

An object of the present invention is to provide an inkjet head maintenance device, an inkjet recording apparatus, and an inkjet head maintenance method that can perform appropriate maintenance more reliably.

In order to achieve the above object, the invention of an ink ejection head maintenance device according to claim 1 is as follows:
a cleaning liquid storage section that stores cleaning liquid;
a wiping member having an outer circumferential surface that can be impregnated with a liquid and performing a wiping operation of wiping an ink ejection surface of an ink ejection head that moves relatively with the rotating outer circumferential surface;
a squeezing portion that squeezes the liquid impregnated into the wiping member into the cleaning liquid storage portion;
a control unit;
Equipped with
The control unit includes:
performing the first wiping operation with the wiping member while a part of the wiping member is immersed in the cleaning liquid in the cleaning liquid reservoir;
After the first wiping operation is completed, while the liquid impregnated in the wiping member is squeezed out by the squeezing portion, the cleaning liquid in the cleaning liquid storage portion is further removed from the ink ejection surface than during the first wiping operation. performing the second wiping operation with the wiping member while the distance to the liquid level is large;
When performing the first wiping operation, suppression control is performed to suppress bubbling of the cleaning liquid in the cleaning liquid storage section.

The invention according to claim 2 is the ink ejection head maintenance apparatus according to claim 1, comprising:
The control section is characterized in that the controller causes the wiping member to perform the second wiping operation in a state where the amount of the cleaning liquid in the cleaning liquid storage section is reduced from that during the first wiping operation.

The invention according to claim 3 is the ink ejection head maintenance device according to claim 1 or 2, comprising:
The control unit is characterized in that the wiping member performs the second wiping operation in a state where the wiping member is not immersed in the cleaning liquid in the cleaning liquid storage unit.

The invention according to claim 4 is the ink ejection head maintenance device according to any one of claims 1 to 3, comprising:
The control unit may perform the suppression control to adjust the amount of liquid squeezed out from the wiping member per unit time by the squeezing unit to a predetermined reference amount or less when the wiping member performs the first wiping operation. It is characterized by doing.

The invention according to claim 5 is the ink ejection head maintenance device according to any one of claims 1 to 3, comprising:
The control unit is characterized in that, when causing the wiping member to perform the first wiping operation, the control unit performs the suppression control to prevent the throttle unit from squeezing out liquid from the wiping member.

The invention according to claim 6 is the ink ejection head maintenance device according to any one of claims 1 to 5,
The control unit is characterized in that, when causing the wiping member to perform the first wiping operation, the control unit performs the suppression control to make the rotational speed of the wiping member slower than the rotational speed in the second wiping operation. There is.

The invention according to claim 7 is the ink ejection head maintenance device according to any one of claims 1 to 6, comprising:
The control unit includes:
When causing the second wiping operation to be performed by the wiping member, rotating the wiping member in a rotation direction in which a portion of the wiping member that abuts the constriction portion is directed toward the top in the vertical direction;
When the wiping member performs the first wiping operation, the suppression control is performed to rotate the wiping member in a direction opposite to the rotation direction in the second wiping operation.

The invention according to claim 8 is the ink ejection head maintenance device according to any one of claims 1 to 7,
a first unit including a first cleaning liquid storage section, a first wiping member, and a first constriction section;
a second unit including a second cleaning liquid storage section, a second wiping member, and a second constriction section;
Equipped with
The control section causes the first wiping member of the first unit to perform the first wiping operation, and causes the second wiping member of the second unit to perform the second wiping operation. It is characterized by

The invention according to claim 9 is the ink ejection head maintenance device according to any one of claims 1 to 8, comprising:
The cleaning liquid is characterized in that it is pure water.

The invention according to claim 10 provides the ink ejection head maintenance apparatus according to any one of claims 1 to 8 ,
The cleaning liquid is characterized in that it contains at least a portion of a pH adjuster, a low volatile component, and an antifoaming agent.

The invention according to claim 11 provides the ink ejection head maintenance apparatus according to any one of claims 1 to 10,
The control unit is characterized in that the wiping member is immersed in the cleaning liquid in the cleaning liquid storage unit after the second wiping operation is completed.

Furthermore, in order to achieve the above object, the invention of an inkjet recording apparatus according to claim 12 is as follows:
the ink ejection head;
The ink ejection head maintenance device according to any one of claims 1 to 11,
a moving unit that relatively moves the wiping member of the maintenance device and the ink ejection head in a direction along the ink ejection surface;
It is characterized by having the following.

The invention according to claim 13 is the inkjet recording apparatus according to claim 12,
The present invention is characterized by comprising a movement control section that controls the moving section so that the speed of the relative movement in the second wiping operation is slower than the speed of the relative movement in the first wiping operation.

Furthermore, in order to achieve the above object, the invention of an ink ejection head maintenance method according to claim 14 is as follows:
a cleaning liquid reservoir for storing a cleaning liquid; a wiping member having an outer circumferential surface that can be impregnated with liquid and performing a wiping operation of wiping an ink ejection surface of an ink ejection head that moves relatively with the rotating outer circumferential surface; and the wiping member. A method for maintaining an ink ejection head using a maintenance device comprising: a squeezing portion for squeezing liquid impregnated into the member into the cleaning liquid storage portion;
a first wiping step of causing the wiping member to perform the first wiping operation in a state where a portion of the wiping member is immersed in the cleaning liquid in the cleaning liquid reservoir;
After the first wiping operation is completed, while the liquid impregnated in the wiping member is squeezed out by the squeezing portion, the cleaning liquid in the cleaning liquid storage portion is further removed from the ink ejection surface than during the first wiping operation. a second wiping step in which the wiping member performs the second wiping operation while the distance to the liquid surface is large;
a suppressing step of performing suppression control to suppress bubbling of the cleaning liquid in the cleaning liquid storage section when performing the first wiping operation;
It is characterized by including.

According to the present invention, there is an effect that appropriate maintenance can be performed more reliably.

1 is a diagram showing a schematic configuration of an inkjet recording apparatus. FIG. 3 is a diagram showing a detailed configuration of a cleaning unit. FIG. 1 is a block diagram showing the functional configuration of an inkjet recording apparatus. It is a figure explaining the 1st wiping operation. It is a figure explaining the 2nd wiping operation. 3 is a flowchart showing a control procedure for maintenance processing. FIG. 7 is a diagram illustrating a second wiping operation according to Modification 1. FIG. FIG. 7 is a diagram illustrating a first wiping operation according to Modification 2. FIG. FIG. 7 is a diagram illustrating a first wiping operation according to Modification 3. FIG. 7 is a diagram illustrating the configuration and maintenance operation of a cleaning section according to Modification 4. FIG.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an inkjet head maintenance apparatus, an inkjet recording apparatus, and an inkjet head maintenance method of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of an inkjet recording apparatus 1 according to an embodiment of the present invention.
The inkjet recording apparatus 1 includes a transport section 10, an image recording section 20, a cleaning unit 30, a control section 40 (see FIG. 3), and the like. Of these, the cleaning unit 30 and the control section 40 constitute a maintenance device 100 (see FIG. 3).

The conveyance unit 10 includes a pair of conveyance rollers 11, a platen 12, and the like.
The pair of transport rollers 11 are driven by a transport motor (not shown) to rotate around a rotation axis parallel to the X direction in FIG. 1 . Thereby, the recording medium S spanned by the pair of transport rollers 11 is transported in a predetermined transport direction (Y direction in FIG. 1).
The platen 12 is a plate-shaped member arranged between the pair of conveyance rollers 11 so that its upper surface is substantially horizontal. The platen 12 supports the recording medium S on its upper surface. Alternatively, a configuration may be adopted in which the platen 12 is provided with a ventilation hole and the recording medium S is attracted to the upper surface of the platen 12 by suctioning air from the side opposite to the recording medium S.
The configuration of the conveyance unit 10 is not limited to the above, but may include, for example, a configuration in which an endless conveyance belt is stretched around a pair of conveyance rollers 11, and the recording medium S is conveyed by the conveyance belt that rotates in accordance with the rotation of the conveyance rollers 11. It may be.

The image recording unit 20 includes four ink ejection heads 21 corresponding to four color inks, yellow (Y), magenta (M), cyan (C), and black (K), and these four ink ejection heads 21. The carriage 22 is movable while being held.

The ink ejection head 21 uses the openings of a plurality of nozzles 211 (see FIG. 2) provided on the ink ejection surface facing the platen 12 to inject the recording medium S transported by the transport unit 10 based on image data. Eject ink. On the ink ejection surface of the ink ejection head 21, the openings of the nozzles 211 are arranged one-dimensionally in the Y direction to form a nozzle row. Note that the ink ejection head 21 may be provided with a plurality of nozzle rows in which the positions of the openings of the nozzles 211 are shifted from each other in the Y direction.
The method of ejecting ink from the nozzle 211 is not particularly limited, but for example, a piezoelectric element such as a piezo element is provided on the wall of the pressure chamber communicating with the nozzle 211, and the piezoelectric element (therefore, the pressure chamber) is deformed to A method can be used in which ink is ejected from the nozzle 211 by causing pressure fluctuations in the ink.
The four ink ejection heads 21 are held by the carriage 22 in a state where they are arranged at predetermined intervals in the X direction. The number of ink ejection heads 21 may be three or less or five or more depending on the number of colors used to record an image.

The carriage 22 is provided movably by a carriage moving section 51 (see FIG. 3) along a guide member (not shown) extending in the X direction. By performing an operation (main scanning) to eject ink from each ink ejection head 21 while moving the carriage 22 holding the ink ejection head 21 in the X direction, a predetermined range (nozzle row An image can be recorded by causing ink to land on a band-shaped area (the area where the image is formed). The inkjet recording apparatus 1 records an image on a predetermined area of the recording medium S by repeatedly performing this main scanning and an operation (sub-scanning) of conveying the recording medium S a predetermined distance in the Y direction. In the following, the position of the carriage when performing main scanning and recording an image will also be referred to as image recording position A1.

Further, the carriage 22 is movable along the X direction to a maintenance position A2 where the ink ejection surface of the ink ejection head 21 faces the cleaning unit 30. That is, the carriage 22 is capable of reciprocating in the X direction between the image recording position A1 and the maintenance position A2.

The cleaning unit 30 includes a cleaning roller 32 (wiping member) that rotates around a rotation axis extending in the X direction, and wipes and cleans the ink ejection surface of the ink ejection head 21 that has been moved to the maintenance position A2 with the cleaning roller 32. do. The length of the cleaning roller 32 in the X direction (longitudinal direction) is longer than the length of the ink ejection surface of one ink ejection head 21 in the X direction.

The cleaning unit 30 is provided movably in the X direction and the Y direction by a cleaning unit moving section 52 (moving section) (see FIG. 3). The cleaning unit 30 moves in the Y direction with the cleaning roller 32 in contact with the ink ejection surface of one ink ejection head 21, thereby cleaning the ink ejection surface of the ink ejection head 21 along its longitudinal direction. Dispel. Specifically, the cleaning unit 30 performs a first wiping operation for one ink ejection head 21 to wipe the ink ejection surface while moving in the +Y direction, and after the first wiping operation, moves in the -Y direction. while performing a second wiping operation of wiping the ink ejection surface. Details of the first wiping operation and the second wiping operation will be described later.
Further, after the first wiping operation and the second wiping operation for one ink ejection head 21 are completed, the cleaning unit 30 moves in the X direction to clean the ink ejection surface of the adjacent ink ejection head 21. The roller 32 is brought into contact and moved in the Y direction again to wipe the ink ejection surface. By repeating this operation, the cleaning unit 30 wipes and cleans the ink ejection surfaces of the four ink ejection heads 21.
Depending on the width of the cleaning roller 32 in the X direction, the ink ejection surfaces of two or more ink ejection heads 21 may be wiped by one movement in the Y direction.

FIG. 2 is a diagram showing a detailed configuration of the cleaning unit 30.
The cleaning unit 30 includes a cleaning liquid storage section 31, a cleaning roller 32, a squeeze rod 33 (throttling section), a cleaning liquid supply pump 34, a cleaning liquid discharge valve 35, a liquid amount detection section 36, and the like.

The cleaning liquid reservoir 31 is a rectangular parallelepiped-shaped container with an open top surface, and stores the cleaning liquid 90 therein. A cleaning liquid supply passage 311 and a cleaning liquid discharge passage 312 communicate with the cleaning liquid storage section 31 . A cleaning liquid supply pump 34 is provided in the cleaning liquid supply channel 311 , and the cleaning liquid 90 is supplied to the cleaning liquid storage section 31 by this cleaning liquid supply pump 34 . Further, the cleaning liquid discharge channel 312 is provided with a cleaning liquid discharge valve 35, and when the cleaning liquid discharge valve 35 is opened, the cleaning liquid 90 in the cleaning liquid reservoir 31 is discharged to the outside.
Note that the cleaning liquid reservoir 31 is not limited to the rectangular parallelepiped shape shown in FIG. 2; for example, the side walls may be inclined as necessary, or the opening on the top surface or the bottom surface may have a shape other than a rectangle. Also good.

As the cleaning liquid 90, for example, pure water is used. Moreover, various solvents may be used as the cleaning liquid 90. Furthermore, a surfactant or the like may be added to the cleaning liquid 90 as appropriate to increase cleaning power. Further, it is preferable to add a basic compound or the like as a pH adjuster in order to promote redissolution and redispersion of the acidic content-containing resin and the like contained in the ink. Further, it is preferable to add a low-volatile component such as a high-boiling organic solvent or a hydrophilic polymer compound because drying of the cleaning liquid 90 can be suppressed. Further, it is preferable to include an antifoaming agent in that the cleaning liquid 90 is less likely to generate foam.

The cleaning roller 32 includes a roller shaft 322 that extends in the X direction, and an absorbing member 321 that is provided around the roller shaft 322 and has a cylindrical shape and is capable of absorbing liquid. That is, the outer peripheral surface of the cleaning roller 32 is made of an absorbing member 321. The absorbing member 321 is fixed to the roller shaft 322, and rotates together with the roller shaft 322 when the roller shaft 322 is rotationally driven by the roller drive unit 37 (see FIG. 3). The roller drive unit 37 is also capable of rotating the roller shaft 322 in a direction opposite to the rotation direction in FIG. 2 . Further, the roller drive section 37 is capable of adjusting the rotation speed of the roller shaft 322.
Depending on the amount of the cleaning liquid 90 in the cleaning liquid storage section 31, a part of the cleaning roller 32 is immersed in the cleaning liquid 90. When the cleaning roller 32 rotates with a portion immersed in the cleaning liquid 90, the portion of the absorbing member 321 that is immersed in the cleaning liquid 90 as it rotates sequentially absorbs the cleaning liquid 90, and becomes impregnated with the cleaning liquid 90.

As the absorbent member 321, for example, a sponge-like flexible porous material can be used. Porous materials include those having open cells made of plastic polymer, for example polyurethane. The absorbing member 321 made of such a material can absorb and impregnate the cleaning liquid 90 and the ink on the ink ejection surface 21a of the ink ejection head 21.
The roller shaft 322 is preferably made of a material that has high rigidity and is resistant to rust; for example, stainless steel can be used.

The cleaning unit 30 can be moved up and down in the Z direction by a cleaning unit moving section 52, and there is a state where the cleaning roller 32 is in contact with the ink ejection surface 21a (the state shown in FIG. 2), and a state where the cleaning roller 32 is in contact with the ink ejection surface 21a (the state shown in FIG. 2). It is possible to switch between a state (not shown) of retracting downward and not coming into contact with the ink ejection surface 21a. In the following, the position of the cleaning unit 30 when the cleaning roller 32 is in contact with the ink ejection surface 21a is also referred to as the "contact position", and the position of the cleaning unit 30 when the cleaning roller 32 is not in contact with the ink ejection surface 21a is also referred to as the "contact position". Also referred to as "evacuation position." The contact position is set such that the distance from the roller shaft 322 to the ink ejection surface 21a is smaller than the thickness of the absorbing member 321. As a result, at the abutting position, the outer peripheral surface 321a of the absorbing member 321 is brought into pressure contact with the ink ejection surface 21a, forming an abutting surface with a predetermined area. When the cleaning unit 30 in the contact position moves in the Y direction, the cleaning roller 32 moves relative to the ink ejection surface and contacts the rotating outer circumferential surface 321a (above contact surface) of the absorbing member 321. Wipe and clean the ink ejection surface 21a. In this specification, the operation in which the cleaning roller 32 wipes the ink ejection surface 21a with the outer peripheral surface 321a of the absorbing member 321 is referred to as a wiping operation.
Note that instead of moving the entire cleaning unit 30 up and down in the Z direction, the cleaning roller 32 may be moved up and down in the Z direction within the cleaning unit 30.

The aperture rod 33 is a cylindrical member disposed on the upstream side of the contact position with the ink ejection surface 21a with respect to the rotating direction of the absorbing member 321 in FIG. The aperture rod 33 is made of a material harder than the absorbing member 321, such as hard rubber or stainless steel.
The squeeze rod 33 presses the outer circumferential surface of the absorbent member 321 in the radial direction, thereby squeezing out the liquid impregnated in the absorbent member 321 into the cleaning liquid reservoir 31 . Here, the liquid impregnated into the absorbing member 321 includes at least one of the cleaning liquid 90 and the ink wiped off from the ink ejection surface 21a. The aperture rod 33 is movable by a aperture rod moving section 38 (see FIG. 3), and by this movement, the distance between the cleaning roller 32 and the roller shaft 322 can be changed. By adjusting the distance between the squeeze rod 33 and the roller shaft 322, the amount of liquid squeezed out of the absorption member 321 by the squeeze rod 33, that is, the amount of liquid impregnated in the absorption member 321, can be adjusted to a desired value. . In the following, the position of the aperture rod 33 when the aperture rod 33 presses the absorption member 321 to squeeze out liquid from the absorption member 321 is referred to as the "pressing position", and the position of the aperture rod 33 when the aperture rod 33 is not in contact with the absorption member 321 is referred to as the "pressing position". The position is described as the "non-pressed position."

Note that the aperture rod 33 is not limited to a cylindrical member, and may be a spatula-shaped plate member, for example.
Further, the aperture rod 33 may be rotatable around a rotation axis extending in the X direction. In this case, by following the rotation of the absorbing member 321 and pressing the absorbing member 321 while rotating, the liquid is squeezed out from the absorbing member 321 and the amount of impregnation is adjusted. By using the rotatable aperture rod 33, wear due to friction between the absorbing member 321 and the aperture rod 33 can be reduced.

The liquid amount detection unit 36 detects the height of the liquid level of the cleaning liquid 90 in the cleaning liquid storage unit 31, and transmits the detection result to the control unit 40 (see FIG. 3).

FIG. 3 is a block diagram showing the functional configuration of the inkjet recording apparatus 1. As shown in FIG.
The inkjet recording apparatus 1 includes a control section 40, an image recording section 20 having an ink ejection head 21 and a head control section 23, a cleaning liquid supply pump 34, a cleaning liquid discharge valve 35, a liquid amount detection section 36, a roller drive section 37, and an aperture. It includes a cleaning unit 30 having a rod moving section 38, a carriage moving section 51, a cleaning unit moving section 52, a transport control section 53, an operation display section 54, a communication section 55, etc., and each of these sections is connected to a bus 56. are connected so that signals can be sent and received via the In the following, description of the components already described will be omitted.

The control unit 40 centrally controls the entire operation of the inkjet recording apparatus 1. The control unit 40 includes a CPU 41 (Central Processing Unit), a RAM 42 (Random Access Memory), a storage unit 43, and the like.

The CPU 41 reads out a control program stored in the storage unit 43 and performs various control processes related to image recording, its settings, and the like.
The RAM 42 provides a working memory space for the CPU 41 and stores temporary data.
The storage unit 43 includes a nonvolatile memory that stores control programs, setting data, and the like. Further, the storage unit 43 may include a DRAM or the like that temporarily stores settings related to image recording commands (print jobs) acquired from the outside via the communication unit 55, image data of recorded images, and the like.

The head control unit 23 causes the nozzles 211 to eject ink in an amount corresponding to the pixel value of the image data by supplying a drive signal to the piezoelectric element of the ink ejection head 21 at an appropriate timing according to the image data. .

The cleaning liquid supply pump 34 of the cleaning unit 30 feeds the cleaning liquid 90 to the cleaning liquid storage section 31 in response to a control signal supplied from the control section 40 .

The cleaning liquid discharge valve 35 opens and closes in response to a control signal supplied from the control unit 40. The control unit 40 discharges a desired amount of the cleaning liquid 90 from the cleaning liquid storage unit 31 by adjusting the opening time of the cleaning liquid discharge valve 35 .

The roller drive unit 37 operates a motor that rotates the cleaning roller 32 based on the control signal supplied from the control unit 40, thereby rotating the cleaning roller 32 at an appropriate speed and rotation direction.

The aperture rod moving unit 38 outputs a drive signal to the motor of the movement mechanism that moves the aperture rod 33 based on the control signal supplied from the control unit 40, and moves the aperture rod 33 to the above-mentioned pressed position and non-pressed position. Move between.

The carriage moving unit 51 outputs a drive signal to the motor and brake of the moving mechanism that moves the carriage 22 in the X direction based on the control signal supplied from the control unit 40, and controls the movement of the carriage 22 related to the above-mentioned main scanning. The carriage 22 is moved between the image recording position A1 and the maintenance position A2.

The cleaning unit moving unit 52 moves the cleaning unit 30 by outputting a drive signal to the motor and brake of the movement mechanism that moves the cleaning unit 30 in the X direction and the Y direction based on the control signal supplied from the control unit 40. let That is, the cleaning unit moving section 52 relatively moves the cleaning roller 32 of the maintenance device 100 and the ink ejection head 21 in the direction along the ink ejection surface 21a. Further, the cleaning unit moving section 52 outputs a drive signal to the motor and brake of the moving mechanism that moves the cleaning unit 30 in the Z direction based on the control signal supplied from the control section 40 to move the cleaning unit 30 up and down. and move between the above-mentioned contact position and retracted position. The control section 40 functions as a movement control section that controls the cleaning unit movement section 52.

The conveyance control unit 53 operates a motor that rotates the conveyance roller 11 to rotate the conveyance roller 11 at an appropriate speed and timing. This transport control section 53 may have a common configuration with the control section 40.

The operation display unit 54 displays status information, menus, etc. related to image recording, and accepts input operations from the user. The operation display unit 54 includes, for example, a display screen using a liquid crystal panel, a driver for the liquid crystal panel, and a touch panel provided on top of the liquid crystal screen, and displays a display screen according to the position where a touch operation is performed by the user and the type of operation. The operation detection signal is output to the control section 40.

The communication unit 55 transmits and receives data to and from external devices according to a predetermined communication standard. The communication unit 55 includes a connection terminal related to the communication standard to be used, driver hardware (network card) related to communication connection, and the like.

Next, a maintenance operation of the ink ejection head 21 by the maintenance device 100 included in the inkjet recording apparatus 1 will be explained.
When the nozzles 211 of the ink ejection head 21 eject ink, some of the ejected ink may adhere to the ink ejection surface 21a. In particular, after a purge operation is performed to eject a large amount of ink from the nozzle 211 in order to prevent clogging of the nozzle 211, ink may adhere in the form of icicles to the ink ejection surface 21a. Further, foreign matter other than ink may also adhere to the ink ejection surface 21a. A maintenance operation is performed by the maintenance device 100 in order to remove these inks and foreign substances from the ink ejection surface 21a.

As described above, when performing maintenance operations on the ink ejection head 21, the carriage 22 is moved to the maintenance position A2, and the cleaning unit 30 is moved while the rotating cleaning roller 32 of the cleaning unit 30 is in contact with the ink ejection surface 21a. Move in the +Y direction or -Y direction. As a result, the cleaning roller 32 performs a wiping operation, and the ink and foreign matter adhering to the ink ejection surface 21a are wiped off and cleaned.

As shown in FIG. 2, by immersing the absorbing member 321 in the cleaning liquid 90 and performing the wiping operation while squeezing out the liquid (here, the cleaning liquid 90) inside the absorbing member 321 with the squeeze rod 33, ink can be effectively discharged. The surface 21a can be wiped away. That is, in this method, a predetermined amount of the cleaning liquid 90 impregnated in the absorbing member 321 is squeezed out by the squeezing rod 33 according to the rotation of the cleaning roller 32, and then the outer peripheral surface 321a of the absorbing member 321 is applied to the ink ejection surface 21a. Since the ink is wiped off, the ink on the ink ejection surface 21a can be efficiently absorbed by the absorbing member 321 and removed. The portion of the absorbing member 321 that has absorbed the ink is immersed in the cleaning liquid 90 as the cleaning roller 32 rotates. As a result, the ink inside the absorbing member 321 is washed away, and the absorbing member 321 is again impregnated with the cleaning liquid 90. By repeating this cycle, the ink on the ink ejection surface 21a can be effectively wiped away.

However, in this method, bubbles may be generated and remain in the cleaning liquid storage section 31 as described below.
After the absorbing member 321 is pressed by the squeeze rod 33 and the cleaning liquid 90 is squeezed out, the absorbing member 321 takes in air when it restores its shape. As a result, the next time the cleaning liquid 90 is squeezed out by the squeezing rod 33, the air taken in is discharged together with the cleaning liquid 90, and becomes bubbles B (see FIG. 2) and stays on the surface of the cleaning liquid 90 in the cleaning liquid storage section 31. .
This bubble B poses no problem if it is in a small amount, but if a large amount stays in the cleaning liquid reservoir 31, it may adhere to the ink ejection surface 21a either directly or via the cleaning roller 32. If the bubbles B adhere to the ink ejection surface 21a, this will lead to ink ejection failure from the nozzle 211.

On the other hand, by performing the wiping operation with the squeezing rod 33 moved to the non-pressing position, the cleaning liquid 90 is no longer squeezed out by the squeezing rod 33, so generation of bubbles B can be suppressed. However, in this method, the portion of the absorbing member 321 that comes into contact with the ink ejection surface 21a is impregnated with a large amount of the cleaning liquid 90, so the absorbing member 321 cannot absorb ink, and the cleaning efficiency decreases. Ink remains after wiping.

Therefore, in this embodiment, by performing the first wiping operation and the second wiping operation in this order on one ink ejection surface 21a, the ink ejection surface can be effectively wiped while suppressing problems caused by bubbles. Wipe out 21a.
Among these, the first wiping operation is performed in a state where foaming of the cleaning liquid 90 is suppressed. In other words, when performing the first wiping operation, the control unit 40 also performs suppression control for suppressing foaming of the cleaning liquid. For example, by moving the squeeze rod 33 to a non-pressing position, foaming of the cleaning liquid 90 is suppressed. The ink that could not be completely wiped away by this first wiping operation is wiped away by the subsequent second wiping operation.
The second wiping operation is performed while squeezing out the liquid impregnated in the absorbing member 321 with the squeezing rod 33, and from the ink ejection surface 21a to the liquid level of the cleaning liquid 90 in the cleaning liquid storage section 31 compared to the first wiping operation. The distance (hereinafter referred to as liquid level separation distance) is large. By increasing the liquid level separation distance, the problem of bubbles adhering to the ink ejection surface 21a is suppressed.
Hereinafter, the first wiping operation and the second wiping operation will be explained in detail.

FIG. 4 is a diagram illustrating the first wiping operation.
As shown in FIG. 4, the first wiping operation is performed with a portion of the absorbing member 321 immersed in the cleaning liquid 90 in the cleaning liquid storage section 31. In the following, the liquid level separation distance during the first wiping operation will be referred to as d1.
Further, the squeeze rod 33 moves to the non-pressing position, and the liquid in the absorption member 321 is not squeezed out by the squeeze rod 33.

Further, in the first wiping operation, the cleaning roller 32 is rotated at a rotation speed Vr1, and the cleaning unit 30 is moved in the +Y direction at a speed Vm1. The rotational speed Vr1 is slower than the rotational speed Vr2 during a second wiping operation, which will be described later. By slowing down the rotational speed Vr1 in this way, it is also possible to suppress foaming of the cleaning liquid 90.
The rotation direction of the cleaning roller 32 is clockwise when viewed from the +X direction. In other words, the rotation direction is such that the outer circumferential surface 321a of the absorbing member 321 faces the aperture rod 33 and then moves toward the top in the vertical direction. Hereinafter, this rotation direction will be referred to as a normal rotation direction.

As the cleaning unit 30 moves in the +Y direction, the rotating absorbing member 321 wipes the ink ejection surface 21a. Here, the ink on the ink ejection surface 21a is mainly scraped off (swept out) in the +Y direction by the outer peripheral surface 321a of the absorbing member 321, thereby removing ink from the ink ejection surface 21a. This is because, as described above, when the cleaning liquid 90 of the absorbing member 321 is not squeezed out by the squeezing rod 33, almost no ink is absorbed by the absorbing member 321. Since ink is difficult to be absorbed by the absorbing member 321 in this way, ink that could not be wiped off may remain on the ink ejection surface 21a at the end of the first wiping operation.

FIG. 5 is a diagram illustrating the second wiping operation.
When the second wiping operation is performed, the cleaning liquid 90 is discharged from the cleaning liquid storage section 31. In the example of FIG. 5, the cleaning liquid 90 is discharged until the entire absorbing member 321 is not immersed in the cleaning liquid 90. As a result, the second wiping operation is performed in a state where the liquid level separation distance d2 is larger than the liquid level separation distance d1 during the first wiping operation.
Although FIG. 5 shows a state in which some of the cleaning liquid 90 remains in the cleaning liquid storage section 31, all of the cleaning liquid 90 may be discharged from the cleaning liquid storage section 31.

Further, when the second wiping operation is performed, the aperture rod 33 moves to the pressing position. Therefore, in the second wiping operation, the liquid inside the absorbing member 321 is squeezed out by the squeezing rod 33.

In the second wiping operation, the cleaning roller 32 is rotated at a rotation speed Vr2, and the cleaning unit 30 is moved in the -Y direction at a speed Vm2. Here, the rotational speed Vr2 is faster than the rotational speed Vr1 during the first wiping operation. By increasing the rotational speed Vr2 of the cleaning roller 32, the total area of the outer circumferential surface 321a of the absorbing member 321 that comes into contact with each part of the ink ejection surface 21a per unit time can be increased. This allows the absorbing member 321 to absorb and remove ink more efficiently.
Furthermore, the moving speed Vm2 of the cleaning unit 30 is slower than the moving speed Vm1 during the first wiping operation. By slowing down the moving speed Vm2 of the cleaning unit 30, the total area of the outer circumferential surface 321a of the absorbing member 321 that comes into contact with each part of the ink ejection surface 21a per unit time is increased, thereby improving the ink wiping efficiency. I can do it.
The rotation direction of the cleaning roller 32 is the forward rotation direction as in the first wiping operation.

As the cleaning unit 30 moves in the -Y direction, the rotating absorbing member 321 wipes the ink ejection surface 21a. Here, the ink on the ink ejection surface 21a is mainly absorbed by the absorption member 321, thereby removing ink from the ink ejection surface 21a. This is because the liquid impregnated in the absorbing member 321 (absorbed ink here) is squeezed out by the aperture rod 33 immediately before the absorbing member 321 contacts the ink ejection surface 21a, and the liquid can be efficiently absorbed. This is because the absorbing member 321 comes into contact with the ink ejection surface 21a in this state. As a result, ink that could not be wiped away in the first wiping operation is effectively wiped off.

In the second wiping operation, bubbles may be generated when ink is squeezed out from the cleaning roller 32 by the squeezing rod 33, but a large liquid level separation distance d2 from the ink ejection surface 21a to the cleaning liquid 90 is ensured. Therefore, it is possible to suppress the occurrence of problems such as bubbles coming into contact with the ink ejection surface 21a. In other words, the liquid level separation distance d2 is set to be greater than or equal to the lower limit of the distance range in which generated bubbles do not reach the ink ejection surface 21a.

FIG. 6 is a flowchart showing a control procedure by the control unit 40 of maintenance processing for executing maintenance operations.
The maintenance process is started when predetermined maintenance start conditions are met. Here, the maintenance start condition is not particularly limited, but for example, the cumulative time of image recording operations by the image recording unit 20 exceeds a predetermined value, or the number of times of image recording exceeds a predetermined value, etc.

When the maintenance process is started, the control unit 40 transmits a control signal to the carriage moving unit 51 to move the carriage 22 to the maintenance position A2 (step S101). Thereby, the cleaning roller 32 of the cleaning unit 30 is in a state facing the ink ejection surface 21a of the one ink ejection head 21.

The control unit 40 operates the cleaning liquid supply pump 34 to supply the cleaning liquid 90 to the cleaning liquid storage unit 31 (step S102). Here, the control unit 40 refers to the detection result by the liquid amount detection unit 36, and when the amount of the cleaning liquid 90 in the cleaning liquid storage unit 31 reaches a predetermined first storage amount, the cleaning liquid supply pump 34 sends the liquid. Stop the operation. The first storage amount is such that the distance from the ink ejection surface 21a to the surface of the cleaning liquid 90 becomes the liquid surface separation distance d1 in FIG. 4. As a result, a portion of the absorbing member 321 is immersed in the cleaning liquid 90.

The control unit 40 sends a control signal to the aperture rod moving unit 38 to move the aperture rod 33 to the non-pressing position (step S103). The control by which the control unit 40 moves the squeezing rod 33 to the non-pressing position is a "suppression control" for suppressing foaming of the cleaning liquid 90 in the cleaning liquid storage section 31, and the squeezing rod 33 squeezes the cleaning liquid 90 from the absorption member 321. This corresponds to "inhibitory control" that prevents this from happening. Furthermore, step S103 corresponds to a "suppression step" that performs suppression control.

The control unit 40 sends a control signal to the roller drive unit 37 to start rotating the cleaning roller 32 (step S104). Here, the control unit 40 rotates the cleaning roller 32 in the normal rotation direction at a rotation speed Vr1 that is a set value during the first wiping operation. The control by which the control unit 40 rotates the cleaning roller 32 at a rotational speed Vr1 is a "suppression control" for suppressing foaming of the cleaning liquid 90 in the cleaning liquid storage part 31, and the rotational speed Vr1 of the cleaning roller 32 is controlled by a second wiping control. This corresponds to "inhibition control" in which the rotational speed in operation is made slower than Vr2, and step S104 corresponds to a "restraint step" in which inhibition control is performed.

The control unit 40 transmits a control signal to the cleaning unit moving unit 52 to move (raise) the cleaning unit 30 to the contact position, and also moves the cleaning unit 30 in the +Y direction to cause the cleaning roller 32 to 1 wiping operation is performed (step S105: first wiping step). That is, the control unit 40 causes the cleaning roller 32 to perform the first wiping operation while a portion of the absorbing member 321 is immersed in the cleaning liquid 90 in the cleaning liquid storage unit 31.

When the first wiping operation is completed, the control unit 40 opens the cleaning liquid discharge valve 35 to discharge the cleaning liquid 90 from the cleaning liquid reservoir 31 (step S106). Here, the control unit 40 refers to the detection result by the liquid amount detection unit 36 and closes the cleaning liquid discharge valve 35 when the amount of cleaning liquid 90 in the cleaning liquid storage unit 31 has decreased to a predetermined second storage amount. Then, the discharge of the cleaning liquid 90 is stopped. The second storage amount is such that the distance from the ink ejection surface 21a to the liquid level of the cleaning liquid 90 becomes the liquid level separation distance d2 in FIG. 5. As a result, the absorbing member 321 is not immersed in the cleaning liquid 90.

The control unit 40 sends a control signal to the aperture rod moving unit 38 to move the aperture rod 33 to the pressing position (step S107).

The control unit 40 sends a control signal to the roller drive unit 37 to adjust the rotation speed so that the cleaning roller 32 rotates at the rotation speed Vr2 (step S108).

The control unit 40 transmits a control signal to the cleaning unit moving unit 52 to move the cleaning unit 30 in the -Y direction, thereby causing the cleaning roller 32 to perform the second wiping operation (step S109: the second wiping operation). Wiping step). That is, the control unit 40 causes the cleaning roller 32 to remove the second wiping liquid while squeezing out the liquid impregnated in the absorbing member 321 using the squeezing rod 33 and in a state where the liquid level separation distance is larger than that during the first wiping operation. The wiping operation is performed. Further, the control unit 40 causes the cleaning roller 32 to perform a second wiping operation with the amount of cleaning liquid 90 in the cleaning liquid storage unit 31 being reduced compared to the first wiping operation. Here, the control unit 40 determines that the moving speed Vm2 of the cleaning roller 32 in the second wiping operation (speed of relative movement between the cleaning roller 32 and the ink ejection head 21) is slower than the moving speed Vm1 in the first wiping operation. The cleaning unit moving section 52 is controlled so that

When the second wiping operation is completed, the control unit 40 operates the cleaning liquid supply pump 34 to supply the cleaning liquid 90 to the cleaning liquid storage unit 31 until the amount of cleaning liquid 90 in the cleaning liquid storage unit 31 reaches the first storage amount. is supplied (step S110). That is, the control unit 40 immerses the absorbent member 321 in the cleaning liquid 90. As a result, the ink adhering to the absorbing member 321 is washed away by the cleaning liquid 90 and cleaned.

The control unit 40 determines whether cleaning of all ink ejection heads 21 has been completed (step S111). If it is determined that cleaning of any ink ejection head 21 has not been completed (“NO” in step S111), the control unit 40 returns the process to step S103 and cleans the next ink ejection head 21. and performs a first wiping operation and a second wiping operation.

If it is determined that cleaning of all the ink ejection heads 21 has been completed (“YES” in step S111), the control unit 40 sends a control signal to the cleaning unit moving unit 52 to move the cleaning unit 30 to the evacuation position. The cleaning roller 32 is moved (lowered) to evacuate. Further, the control unit 40 sends a control signal to the carriage moving unit 51 to move the carriage 22 to the image recording position A1 (step S112).
When the process of step S112 ends, the control unit 40 ends the maintenance process.

(Modification 1)
Next, a first modification of the above embodiment will be described.
In the above embodiment, the second wiping operation is performed with the absorbing member 321 not immersed in the cleaning liquid 90, but in this modification, the second wiping operation is performed with a part of the absorbing member 321 immersed in the cleaning liquid 90. perform an action. Other points are similar to the above embodiment. Below, differences from the above embodiment will be explained.

FIG. 7 is a diagram illustrating a second wiping operation according to Modification 1.
As shown in FIG. 7, in this modification, when the second wiping operation is performed, the cleaning liquid 90 is discharged from the cleaning liquid storage part 31 within the amount of liquid in which a part of the absorbing member 321 is immersed in the cleaning liquid 90. let Therefore, in this modification, the liquid level separation distance d3 when the second wiping operation is performed is smaller than the liquid level separation distance d2 of the above embodiment, and larger than the liquid level separation distance d1. Similar to the liquid level separation distance d2, the liquid level separation distance d3 is set to be equal to or greater than the lower limit of the distance range in which generated bubbles do not reach the ink ejection surface 21a.

By moving the cleaning unit 30 in the −Y direction in the state shown in FIG. 7 and performing a second wiping operation, the portion of the absorbing member 321 that has absorbed ink is immersed in the cleaning liquid 90 and cleaned. At this time, the absorbing member 321 is impregnated with the cleaning liquid 90, but it is squeezed out by the squeezing rod 33 as it rotates, so that it is in a state where it can absorb ink again when it comes into contact with the ink ejection surface 21a. In this manner, in this modification, ink can be absorbed by the absorbing member 321 while cleaning the absorbing member 321 with the cleaning liquid 90, so that the ink ejection surface 21a can be wiped and cleaned more efficiently.
In addition, bubbles may be generated when the cleaning liquid 90 is squeezed out from the absorbing member 321 by the squeezing rod 33, but since the liquid level separation distance d3 is ensured to be large, the occurrence of a problem in which the bubbles come into contact with the ink ejection surface 21a is prevented. It can be suppressed.

(Modification 2)
Next, a second modification of the above embodiment will be described.
The first wiping operation in the above embodiment was performed by moving the squeeze rod 33 to the non-pressing position and not squeezing out the liquid from the absorbing member 321. However, in this modification, the squeeze rod 33 moves the liquid inside the absorbing member 321. The first wiping operation is performed while squeezing out the liquid. Other points are similar to the above embodiment. Below, differences from the above embodiment will be explained.

FIG. 8 is a diagram illustrating a first wiping operation according to modification 2.
As shown in FIG. 8, in this modification, the position of the aperture rod 33 is adjusted so that the aperture rod 33 slightly presses the absorbing member 321 when the first wiping operation is performed. Specifically, the control unit 40 adjusts the position of the aperture rod 33 so that the amount of liquid that the aperture rod 33 squeezes out from the absorption member 321 per unit time is equal to or less than a predetermined reference amount. Control that adjusts the amount of liquid that the squeeze rod 33 squeezes out from the absorption member 321 per unit time to a reference amount or less is one form of "suppression control."
Here, the above-mentioned reference amount is set below the upper limit of the range in which bubbles generated by squeezing out the liquid by the squeezing rod 33 do not reach the ink ejection surface 21a. Further, the above reference amount is set within a range smaller than the amount of liquid that the squeeze rod 33 squeezes out from the absorbing member 321 per unit time during the second wiping operation.

In this manner, by squeezing out a portion of the liquid in the absorbing member 321 with the squeeze rod 33, the absorbing member 321 can partially absorb the ink on the ink ejection surface 21a. Therefore, in the first wiping operation, ink can be efficiently removed from the ink ejection surface 21a while suppressing bubbling.
Furthermore, if the amount of liquid squeezed out by the squeezing rod 33 is suppressed to a reference amount or less, the ink on the ink ejection surface 21a may not be sufficiently wiped away by the first wiping operation alone; however, the second wiping operation may be further performed. Therefore, the ink on the ink ejection surface 21a can be wiped away more reliably.

(Modification 3)
Next, a third modification of the above embodiment will be described.
In this modification, the aperture rod moving section 38 is not provided, and the position of the aperture rod 33 is fixed. Furthermore, in the first wiping operation, foaming of the cleaning liquid 90 is suppressed by suppressing control in which the rotation direction of the cleaning roller 32 is reversed, instead of suppressing control in which the squeeze rod 33 is moved to the non-pressing position. This modification differs from the embodiment described above in these points, and is similar to the embodiment described above in other respects. Below, differences from the above embodiment will be explained.

FIG. 9 is a diagram illustrating a first wiping operation according to modification 3.
As shown in FIG. 9, in this modification, when the first wiping operation is performed, the position of the aperture rod 33 remains fixed at the pressing position. On the other hand, the control unit 40 rotates the cleaning roller 32 in a reverse direction that is opposite to the rotation direction in the second wiping operation. This reverse direction is a direction in which the portion of the outer circumferential surface 321a of the absorbing member 321 that contacts the aperture rod 33 subsequently moves toward the bottom in the vertical direction. Therefore, the portion of the absorbing member 321 from which the liquid has been squeezed out by the squeezing rod 33 moves downward. Therefore, when the portion of the absorbing member 321 restores its shape, it absorbs the liquid immediately after being squeezed out again, and becomes impregnated with the liquid without taking in much air. Therefore, the next time the liquid is squeezed out by the squeezing rod 33, less air is expelled, making it difficult for bubbles to form.
In this modification, the control to rotate the cleaning roller 32 in the reverse direction is a form of "suppression control" for suppressing foaming of the cleaning liquid 90 in the cleaning liquid storage section 31.

By rotating the cleaning roller 32 in the reverse direction in this manner, even if the aperture rod 33 is fixed, foaming of the cleaning liquid 90 can be suppressed in the first wiping operation.
Further, when the cleaning roller 32 is rotated in the reverse direction, when the absorbing member 321 comes into contact with the ink ejection surface 21a, the absorbing member 321 is impregnated with a large amount of the cleaning liquid 90, so that the ink cannot be absorbed and the ink is ejected. Although there are cases where the ink on the surface 21a cannot be sufficiently wiped, by further performing the second wiping operation, the ink on the ink ejection surface 21a can be wiped more reliably.

(Modification 4)
Next, a fourth modification of the above embodiment will be described.
This modification differs from the above embodiment in that the first wiping operation and the second wiping operation are performed by separate units included in the cleaning unit 30, and is otherwise similar to the above embodiment. Below, differences from the above embodiment will be explained.

FIG. 10 is a diagram illustrating the configuration and maintenance operation of the cleaning unit 30 according to Modification 4.
The cleaning unit 30 of this modification includes a first unit UA and a second unit UB provided at a position adjacent to the first unit UA in the -Y direction. The first unit UA includes a first cleaning liquid reservoir 31A, a first cleaning roller 32A, and a first squeeze rod 33A. Further, the second unit UB includes a second cleaning liquid reservoir 31B, a second cleaning roller 32B, and a second aperture rod 33B. Therefore, the first unit UA and the second unit UB each have the same configuration as the cleaning unit 30 of the above embodiment.

The first unit UA performs the same operation as the cleaning unit 30 when performing the first wiping operation in the above embodiment. That is, in the first unit UA, the absorbing member 321 is immersed in the cleaning liquid 90, the first squeezing rod 33A has moved to the non-pressing position, and the first cleaning roller 32A is rotating normally. direction at a rotational speed Vr1.

The second unit UB performs the same operation as the cleaning unit 30 when performing the second wiping operation in the above embodiment. That is, in the second unit UB, the absorbing member 321 is not immersed in the cleaning liquid 90, the second squeezing rod 33B is moved to the pressing position, and the second cleaning roller 32B is rotated in the normal rotation direction. It rotates at a rotational speed Vr2.

The control unit 40 causes the first cleaning roller 32A of the first unit UA to perform the first wiping operation by moving the first unit UA and second unit UB configured as described above in the +Y direction. Then, the second cleaning roller 32B of the second unit UB performs a second wiping operation. Thereby, the ink ejection surface 21a can be effectively wiped and cleaned in a short time while suppressing the occurrence of problems due to bubbles in each of the first unit UA and the second unit UB.

Note that when cleaning one ink ejection head 21 by moving the first unit UA and the second unit UB in the +Y direction, and then cleaning another ink ejection head 21, the first unit UA and the second unit UB can be moved in the +Y direction. The wiping operation may be performed by moving the first unit UA and the second unit UB in the -Y direction, or by returning the first unit UA and the second unit UB to the left side in FIG. A wiping motion in the direction may also be performed. - When performing a wiping operation in the Y direction, the first wiping operation is performed by the second unit UB on the leading side in the traveling direction, and the second wiping operation is performed by the first unit UA on the rear side in the traveling direction. That's fine.
When the first unit UA performs only the first wiping operation, such as when always performing the wiping operation in the +Y direction, the first aperture rod 33A of the first unit UA may be omitted.

As described above, the maintenance device 100 for the ink ejection head 21 according to the present embodiment has the cleaning liquid storage section 31 that stores the cleaning liquid 90 and the outer circumferential surface 321a that can be impregnated with liquid, and the ink ejection head 21 that moves relatively. A cleaning roller 32 that performs a wiping operation of wiping the ink ejection surface 21a with a rotating outer peripheral surface 321a, a squeeze rod 33 that squeezes out the liquid impregnated in the cleaning roller 32 into the cleaning liquid storage section 31, and a control section 40. In preparation, the control unit 40 causes the cleaning roller 32 to perform a first wiping operation while a part of the cleaning roller 32 is immersed in the cleaning liquid 90 in the cleaning liquid storage unit 31, and after the first wiping operation is completed, the control unit 40 performs the cleaning operation. While squeezing out the liquid impregnated in the roller 32 with the squeezing rod 33, the liquid level deviation distance (distance from the ink ejection surface 21a to the liquid level of the cleaning liquid 90 in the cleaning liquid storage section 31) is greater than during the first wiping operation. When the second wiping operation is performed by the cleaning roller 32 and the first wiping operation is performed in a state where the cleaning roller 32 is large, suppression control is performed to suppress bubbling of the cleaning liquid 90 in the cleaning liquid storage section 31.
According to this, after a certain amount of ink on the ink ejection surface 21a is removed by the first wiping operation, the second wiping operation, which is performed while squeezing out the liquid from the absorption member 321 of the cleaning roller 32 with the squeezing rod 33, removes the ink from the ink ejection surface 21a. Ink left behind by the wiping operation can be absorbed by the absorbing member 321 and can be effectively wiped away.
Further, since suppression control is performed in the first wiping operation, foaming of the cleaning liquid 90 can be suppressed. In addition, in the second wiping operation, by making the liquid level separation distance larger than that in the first wiping operation, it is possible to prevent bubbles generated in the cleaning liquid storage section 31 from adhering to the ink ejection surface 21a. . Therefore, in both the first wiping operation and the second wiping operation, it is possible to suppress the occurrence of ink ejection failure due to bubbles adhering to the ink ejection surface 21a.
Therefore, according to the above configuration, since the ink ejection surface 21a can be effectively wiped while suppressing problems caused by bubbles, maintenance of the ink ejection head 21 can be performed more reliably and appropriately.
Further, since the first wiping operation and the second wiping operation can be performed using one cleaning roller 32, the first wiping operation can be performed using a separate member (for example, a blade) from the cleaning roller 32. The configuration of the maintenance device 100 can be simplified and an increase in manufacturing costs can be suppressed.
Furthermore, even if an antifoaming agent is not added to the cleaning liquid 90 (or even if the amount of antifoaming agent to be added is suppressed), it is possible to suppress the occurrence of problems such as bubbles adhering to the ink ejection surface 21a. 100% running cost can be reduced.

Further, the control unit 40 causes the cleaning roller 32 to perform a second wiping operation with the amount of cleaning liquid 90 in the cleaning liquid storage unit 31 being reduced compared to the first wiping operation. According to this, the liquid level separation distance can be increased by a simple method of discharging the cleaning liquid 90 from inside the cleaning liquid storage section 31.

Further, the control unit 40 causes the cleaning roller 32 to perform the second wiping operation while the cleaning roller 32 is not immersed in the cleaning liquid 90 in the cleaning liquid storage unit 31 . According to this, since the absorbing member 321 of the cleaning roller 32 is not impregnated with the cleaning liquid 90, the amount of liquid squeezed out from the absorbing member 321 by the squeezing rod 33 in the second wiping operation is reduced, and the generation of bubbles is effectively suppressed. can be suppressed.

Further, when the cleaning roller 32 performs the first wiping operation, the control unit 40 performs suppression control to adjust the amount of liquid that the squeeze rod 33 squeezes out of the cleaning roller 32 per unit time to a predetermined reference amount or less. (Modification 2). According to this, the amount of liquid squeezed out from the absorbing member 321 of the cleaning roller 32 by the squeeze rod 33 in the first wiping operation can be reduced, thereby suppressing the generation of bubbles.

Furthermore, when the cleaning roller 32 performs the first wiping operation, the control unit 40 performs suppression control to prevent the squeezing rod 33 from squeezing out the liquid from the cleaning roller 32 . According to this, it is possible to more effectively suppress the generation of bubbles during the first wiping operation.

Further, when causing the cleaning roller 32 to perform the first wiping operation, the control unit 40 performs suppression control to make the rotational speed Vr1 of the cleaning roller 32 slower than the rotational speed Vr2 in the second wiping operation. In the first wiping operation, by slowing down and increasing the rotational speed Vr1 of the cleaning roller 32, it is possible to suppress bubbling caused by the cleaning roller 32 disturbing the surface of the cleaning liquid 90. In addition, when the liquid is squeezed out from the absorbing member 321 by the squeeze rod 33 in the first wiping operation as in Modification 2, the amount of liquid and air squeezed out per unit time can be reduced. Foaming caused by the discharged liquid can be suppressed. Further, wear of the ink ejection surface 21a caused by the cleaning roller 32 can be suppressed.

Further, when the cleaning roller 32 performs the second wiping operation, the control unit 40 controls the cleaning roller 32 so that the portion of the cleaning roller 32 that comes into contact with the aperture rod 33 is rotated in a rotation direction (normal rotation direction) toward the top in the vertical direction. When the cleaning roller 32 is rotated and the cleaning roller 32 performs the first wiping operation, suppression control is performed to rotate the cleaning roller 32 in the opposite direction (reverse direction) to the rotation direction in the second wiping operation. (Modification 3). According to this, in the first wiping operation, the portion of the absorbing member 321 of the cleaning roller 32 from which the liquid has been squeezed out by the squeezing rod 33 moves downward. Therefore, when the portion of the absorbing member 321 restores its shape, it absorbs the liquid immediately after being squeezed out again, and becomes impregnated with the liquid without taking in much air. Therefore, the next time the liquid is squeezed out by the squeezing rod 33, less air is expelled, making it difficult for bubbles to form. By rotating the cleaning roller 32 in the reverse direction in this way, even if the aperture rod 33 is fixed, generation of bubbles during the first wiping operation can be suppressed.

Furthermore, the maintenance device 100 according to the fourth modification includes a first unit UA having a first cleaning liquid storage section 31A, a first cleaning roller 32A, and a first squeezing rod 33A, and a second cleaning liquid storage section 31B. , a second cleaning roller 32B, and a second unit UB having a second aperture rod 33B, and the control unit 40 causes the first cleaning roller 32A of the first unit UA to perform the first wiping operation. and causes the second cleaning roller 32B of the second unit UB to perform a second wiping operation. According to this, the ink ejection surface 21a can be effectively wiped and cleaned in a short time.

Further, by using pure water as the cleaning liquid 90, the ink ejection surface 21a can be efficiently and effectively cleaned.

Further, the cleaning liquid 90 includes at least a portion of a pH adjuster, a low volatile component, and an antifoaming agent. When the cleaning liquid 90 contains a pH adjuster, it is possible to promote redissolution and redispersion of acidic resins and the like contained in the ink to be wiped. Further, since the cleaning liquid 90 contains a low volatile component, drying of the cleaning liquid 90 can be suppressed. Further, since the cleaning liquid 90 contains an antifoaming agent, the cleaning liquid 90 can be made less likely to generate bubbles.

Further, the control unit 40 immerses the cleaning roller 32 in the cleaning liquid 90 in the cleaning liquid storage unit 31 after the second wiping operation is completed. According to this, the ink adhering to the absorbing member 321 of the cleaning roller 32 can be washed away with the cleaning liquid 90 and cleaned.

Furthermore, the inkjet recording apparatus 1 of the present embodiment relatively moves the inkjet head 21, the maintenance device 100, the cleaning roller 32 of the maintenance device 100, and the inkjet head 21 in the direction along the inkjet surface 21a. A cleaning unit moving section 52 is provided. According to this, the ink ejection surface 21a can be effectively wiped while suppressing problems caused by bubbles, so that maintenance of the ink ejection head 21 can be performed more reliably and appropriately.

The control unit 40 also controls the cleaning unit moving unit 52 so that the speed of relative movement in the second wiping operation (moving speed Vm2) is slower than the speed of relative movement in the first wiping operation (moving speed Vm1). control (movement control unit). By slowing the movement speed Vm2 in this manner, the total area of the outer circumferential surface 321a of the absorbing member 321 that contacts each part of the ink ejection surface 21a per unit time is increased, and the ink wiping efficiency in the second wiping operation is increased. can be improved. Further, by making the moving speed Vm1 in the first wiping operation relatively fast, the time required for the maintenance operation can be shortened.

Further, the maintenance method for the ink ejection head 21 according to the present embodiment includes a first wiping operation performed by the cleaning roller 32 while a part of the cleaning roller 32 is immersed in the cleaning liquid 90 in the cleaning liquid storage section 31. After the wiping step and the first wiping operation are completed, while squeezing out the liquid impregnated in the cleaning roller 32 with the squeezing rod 33, the cleaning liquid reservoir 31 is further removed from the ink ejection surface 21a than during the first wiping operation. A second wiping step in which the cleaning roller 32 performs a second wiping operation while the distance to the surface of the cleaning liquid 90 is large; and a second wiping step in which the cleaning roller 32 performs a second wiping operation when the distance to the surface of the cleaning liquid 90 is large; and a suppressing step of performing suppression control to suppress bubbling. According to such a method, the ink ejection surface 21a can be effectively wiped while suppressing problems caused by bubbles, so that maintenance of the ink ejection head 21 can be performed more reliably and appropriately.

Note that the present invention is not limited to the above embodiments, and various changes are possible.
For example, in the above embodiment, the rotational speed Vr1 of the cleaning roller 32 in the first wiping operation is different from the rotational speed Vr2 of the cleaning roller 32 in the second wiping operation, but the invention is not limited to this. The rotational speed of the cleaning roller 32 may be made the same in the wiping operation and the second wiping operation.
Further, although the moving speed Vm1 of the cleaning unit 30 in the first wiping operation and the moving speed Vm2 of the cleaning unit 30 in the second wiping operation are different, the present invention is not limited to this. The moving speed of the cleaning unit 30 may be made the same in the wiping operation.

Further, in the above embodiment, when performing the first wiping operation, the wiping control is performed so that the aperture rod 33 is moved to a non-pressing position to prevent the aperture rod 33 from squeezing out the liquid from the absorption member 321, and the cleaning roller Although the explanation has been given using an example in which wiping control is performed such that the rotational speed Vr1 of No. 32 is slower than the rotational speed Vr2 during the second wiping operation, one of these two controls may be omitted.

Further, in the above embodiment, when performing the second wiping operation, the cleaning liquid 90 is discharged from the cleaning liquid storage section 31 to increase the liquid level separation distance. do not have. For example, the liquid level separation distance may be increased by moving only the cleaning liquid reservoir 31 vertically downward while maintaining the height of the cleaning roller 32.

Further, in the above embodiment, the cleaning unit 30 is moved in the +Y direction in the first wiping operation, and the cleaning unit 30 is moved in the -Y direction in the second wiping operation, but the present invention is not limited to this. For example, after the first wiping operation in the +Y direction, the cleaning unit 30 is returned to its original position, and in the second wiping operation, the cleaning unit 30 is moved in the same direction as the first wiping operation (+Y direction). Good too.

Further, at least one of the first wiping operation and the second wiping operation may be performed for one ink ejection head 21 two or more times.

Further, in the above embodiment, the first wiping operation and the second wiping operation are performed by fixing the ink ejection head 21 and moving the cleaning unit 30, but the invention is not limited to this, and the cleaning unit 30 is fixed. The first wiping operation and the second wiping operation may be performed by moving the ink ejection head 21 (carriage 22). In this case, the carriage moving section 51 corresponds to a "moving section" that moves the cleaning roller 32 and the ink ejection head 21 relative to each other.

Further, in the above embodiment, the rotation axis of the cleaning roller 32 is perpendicular to the longitudinal direction of the ink ejection surface 21a, but the invention is not limited to this. The cleaning roller 32 may be arranged so as to be parallel to the longitudinal direction (in the example of FIG. 1, the rotation axis of the cleaning roller 32 is parallel to the Y direction). In this case, by making the width of the cleaning roller 32 in the rotation axis direction larger than the length in the longitudinal direction of the ink ejection surface, the entire ink ejection surface 21a can be wiped by one movement of the cleaning unit 30. can.

Further, in the above embodiment, the explanation has been given using an example in which the control section 40 of the inkjet recording apparatus 1 controls the operation of each section of the cleaning unit 30, but the invention is not limited to this, and a separate control section may be provided within the cleaning unit 30. The operation of each part of the cleaning unit 30 may be controlled by this control section.

Although the explanation has been given using an example in which the inkjet recording apparatus 1 includes the maintenance apparatus 100, the maintenance apparatus 100 may be provided separately from the inkjet recording apparatus 1.

Further, in the above embodiment, the inkjet recording apparatus 1 which main-scans the ink ejection head 21 together with the carriage 22 to record an image has been described as an example, but the invention is not limited to this, and the width direction of the recording medium S is The present invention is applied to a single-pass inkjet recording device that records an image without moving the inkjet head using an inkjet head (line head) in which a nozzle row is provided over the recording width of the image. You may do so.

Although several embodiments of the present invention have been described, the scope of the present invention is not limited to the above-described embodiments, but includes the scope of the invention described in the claims and equivalents thereof. .

1 Inkjet recording device 10 Transport section 20 Image recording section 21 Ink discharge head 21a Ink discharge surface 211 Nozzle 22 Carriage 23 Head control section 30 Cleaning unit 31 Cleaning liquid storage section 31A First cleaning liquid storage section 31B Second cleaning liquid storage section 32 Cleaning Roller (wiping member)
32A First cleaning roller (first wiping member)
32B Second cleaning roller (second wiping member)
321 Absorbing member 321a Outer peripheral surface 322 Roller shaft 33 Squeezing rod (squeezing part)
33A First aperture rod (first aperture part)
33B Second aperture rod (second aperture part)
34 Cleaning liquid supply pump 35 Cleaning liquid discharge valve 36 Liquid amount detection section 37 Roller drive section 38 Squeezing rod moving section 40 Control section (movement control section)
41 CPU
42 RAM
43 Storage unit 51 Carriage moving unit 52 Cleaning unit moving unit (moving unit)
53 Transport control section 54 Operation display section 55 Communication section 56 Bus 90 Cleaning liquid 100 Maintenance device S Recording medium UA First unit UB Second unit

Claims (14)

a cleaning liquid storage section that stores cleaning liquid;
a wiping member having an outer circumferential surface that can be impregnated with a liquid and performing a wiping operation of wiping an ink ejection surface of an ink ejection head that moves relatively with the rotating outer circumferential surface;
a squeezing portion that squeezes the liquid impregnated into the wiping member into the cleaning liquid storage portion;
a control unit;
Equipped with
The control unit includes:
performing the first wiping operation with the wiping member while a part of the wiping member is immersed in the cleaning liquid in the cleaning liquid reservoir;
After the first wiping operation is completed, while the liquid impregnated in the wiping member is squeezed out by the squeezing portion, the cleaning liquid in the cleaning liquid storage portion is further removed from the ink ejection surface than during the first wiping operation. performing the second wiping operation with the wiping member while the distance to the liquid level is large;
An ink ejection head maintenance device characterized in that when performing the first wiping operation, suppression control is performed to suppress bubbling of the cleaning liquid in the cleaning liquid storage section. 1 . The control unit causes the wiping member to perform the second wiping operation in a state where the amount of the cleaning liquid in the cleaning liquid storage portion is reduced from that during the first wiping operation. The ink ejection head maintenance device described in . 3. The control unit causes the wiping member to perform the second wiping operation in a state where the wiping member is not immersed in the cleaning liquid in the cleaning liquid storage unit. Ink ejection head maintenance device. The control unit may perform the suppression control to adjust the amount of liquid squeezed out from the wiping member per unit time by the squeezing unit to a predetermined reference amount or less when the wiping member performs the first wiping operation. 4. The ink ejection head maintenance device according to claim 1, wherein the ink ejection head maintenance device performs maintenance on an ink ejection head. 1 . The control unit performs the suppression control to prevent the squeezing unit from squeezing out the liquid from the wiping member when the wiping member performs the first wiping operation. 3. The ink ejection head maintenance device according to any one of items 3 to 3. The control unit is characterized in that, when causing the wiping member to perform the first wiping operation, the control unit performs the suppression control to make the rotational speed of the wiping member slower than the rotational speed in the second wiping operation. The ink ejection head maintenance device according to any one of claims 1 to 5. The control unit includes:
When causing the second wiping operation to be performed by the wiping member, rotating the wiping member in a rotation direction in which a portion of the wiping member that abuts the constriction portion is directed toward the top in the vertical direction;
Claim characterized in that, when the wiping member performs the first wiping operation, the suppression control is performed to rotate the wiping member in a direction opposite to the rotation direction in the second wiping operation. 7. The ink ejection head maintenance device according to any one of 1 to 6. a first unit including a first cleaning liquid storage section, a first wiping member, and a first constriction section;
a second unit including a second cleaning liquid storage section, a second wiping member, and a second constriction section;
Equipped with
The control section causes the first wiping member of the first unit to perform the first wiping operation, and causes the second wiping member of the second unit to perform the second wiping operation. The ink ejection head maintenance device according to any one of claims 1 to 7. The ink ejection head maintenance device according to claim 1, wherein the cleaning liquid is pure water. The ink ejection head maintenance device according to any one of claims 1 to 8, wherein the cleaning liquid contains at least a portion of a pH adjuster, a low volatile component, and an antifoaming agent. The ink ejection head according to any one of claims 1 to 10, wherein the control unit immerses the wiping member in the cleaning liquid in the cleaning liquid storage unit after the second wiping operation is completed. maintenance equipment. the ink ejection head;
The ink ejection head maintenance device according to any one of claims 1 to 11,
a moving unit that relatively moves the wiping member of the maintenance device and the ink ejection head in a direction along the ink ejection surface;
An inkjet recording device comprising: Claim 12, further comprising a movement control unit that controls the moving unit so that the speed of the relative movement in the second wiping operation is slower than the speed of the relative movement in the first wiping operation. The inkjet recording device described in . a cleaning liquid reservoir for storing a cleaning liquid; a wiping member having an outer circumferential surface that can be impregnated with liquid and performing a wiping operation of wiping an ink ejection surface of an ink ejection head that moves relatively with the rotating outer circumferential surface; and the wiping member. A method for maintaining an ink ejection head using a maintenance device comprising: a squeezing portion for squeezing liquid impregnated into the member into the cleaning liquid storage portion;
a first wiping step of causing the wiping member to perform the first wiping operation in a state where a portion of the wiping member is immersed in the cleaning liquid in the cleaning liquid reservoir;
After the first wiping operation is completed, while the liquid impregnated in the wiping member is squeezed out by the squeezing portion, the cleaning liquid in the cleaning liquid storage portion is further removed from the ink ejection surface than during the first wiping operation. a second wiping step in which the wiping member performs the second wiping operation while the distance to the liquid surface is large;
a suppressing step of performing suppression control to suppress bubbling of the cleaning liquid in the cleaning liquid storage section when performing the first wiping operation;
A method for maintaining an ink ejection head, the method comprising:

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