Cleaning device and liquid dispensing device

Abstract

To provide a cleaning device that can be made smaller. [Solution] The cleaning device 9 cleans both the liquid discharge head 32 that discharges liquid onto the sheet and the roller 34 that moves while in contact with the surface of the sheet.

Description

Technical Field

[0001] The present invention relates to a cleaning device and a liquid ejection device.

Background Art

[0002] In some liquid ejection devices such as inkjet image forming devices, there is a cleaning device for cleaning a liquid ejection head that ejects liquid onto a sheet.

[0003] By the way, in Patent Document 1 (Japanese Patent Application Laid-Open No. 2019-25668), as a liquid ejection device, there is proposed one including a leveling part that contacts the sheet to level the surface of the sheet in order to suppress the fluffing of the sheet, and a cleaning part that cleans the leveling part.

[0004] By providing a cleaning part for cleaning the leveling part as in Patent Document 1, it is possible to remove the dirt adhering to the leveling part. However, in order to clean the leveling part, there is a problem that the entire device becomes larger when a dedicated cleaning device (cleaning part) is additionally provided.

Summary of the Invention

Problems to be Solved by the Invention

[0005] Therefore, an object of the present invention is to provide a cleaning device that can be miniaturized.

Means for Solving the Problems

[0006] In order to solve the above problems, the cleaning device according to the present invention is characterized by cleaning both a liquid ejection head that ejects liquid onto a sheet and a roller that moves while contacting the surface of the sheet.

Effects of the Invention

[0007] According to the present invention, the device can be miniaturized.

Brief Description of the Drawings

[0008] [Figure 1] This is a plan view showing the overall configuration of an image forming apparatus according to the first embodiment of the present invention. [Figure 2] This is a front view showing the operation of the leveling process in an image forming apparatus according to the first embodiment of the present invention. [Figure 3] This is a front view showing the operation of the pretreatment solution application step in an image forming apparatus according to the first embodiment of the present invention. [Figure 4] This is a front view of an image forming apparatus equipped with a height detection sensor. [Figure 5] This is a diagram illustrating the method of height detection using a height detection sensor. [Figure 6] This is a diagram illustrating the method of height detection using a height detection sensor. [Figure 7] This figure shows examples of other height detection sensors. [Figure 8] This diagram shows how a leveling roller performs the leveling process while avoiding the protrusions on the sheet. [Figure 9] This is a schematic diagram showing the basic configuration of a maintenance unit according to the first embodiment of the present invention. [Figure 10] This is a block diagram showing the configuration of a control unit included in an image forming apparatus according to a first embodiment of the present invention. [Figure 11] This figure shows the configuration and cleaning operation of a pre-treatment maintenance unit according to the first embodiment of the present invention. [Figure 12] This figure shows the configuration and cleaning operation of a pre-treatment maintenance unit according to the first embodiment of the present invention. [Figure 13] This is a flowchart showing the cleaning operation of the pre-treatment maintenance unit according to the first embodiment of the present invention. [Figure 14] This figure shows the configuration and cleaning operation of a pre-treatment maintenance unit according to a second embodiment of the present invention. [Figure 15] This is a flowchart showing the cleaning operation of the pre-treatment maintenance unit according to the second embodiment of the present invention. [Figure 16] This diagram shows the positional relationship between the position where the cleaning solution is applied to the leveling roller and the contact position where the wiping member makes contact. [Figure 17] It is a flowchart showing the cleaning operation of the pretreatment maintenance unit according to the third embodiment of the present invention. [Figure 18] It is a diagram showing the configuration and cleaning operation of the pretreatment maintenance unit according to the third embodiment of the present invention. [Figure 19] It is a flowchart showing an example of the cleaning timing for cleaning the leveling roller.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, the present invention will be described based on the accompanying drawings. In each drawing for explaining the present invention, components such as members and components having the same function or shape are given the same reference numerals as far as possible to be distinguishable, and the description thereof will be omitted after being explained once.

[0010] First, the configuration of the liquid ejection device according to the first embodiment of the present invention will be described by taking an inkjet type image forming apparatus as an example.

[0011] <Overall Configuration of the Image Forming Apparatus> FIG. 1 is a plan view showing the overall configuration of an image forming apparatus 100 according to the first embodiment of the present invention.

[0012] Here, the X direction, Y direction, and Z direction in FIG. 1 are arbitrarily defined as the respective directions of the three-dimensional coordinate axes of the image forming apparatus 100 according to the first embodiment of the present invention. Specifically, the X direction indicates the horizontal direction when the image forming apparatus 100 is viewed from above, and the Y direction indicates the vertical direction orthogonal to the X direction (horizontal direction) when the image forming apparatus 100 is viewed from above. The Z direction indicates the direction orthogonal to each of the X direction and Y direction when the image forming apparatus 100 is viewed from above (for example, the vertically upward direction when the image forming apparatus 100 is placed on a plane). In other drawings, the X direction, Y direction, and Z direction also indicate the same directions as those in FIG. 1, respectively.

[0013] As shown in FIG. 1, an image forming apparatus 100 according to a first embodiment of the present invention includes a sheet conveyance unit 1, an image forming unit 2, a preprocessing unit 3, an image forming maintenance unit 4, and a preprocessing maintenance unit 5.

[0014] The sheet conveyance unit 1 includes a placement portion 11 on which a sheet S as a recording medium is placed, and a guide rail 12 that guides the placement portion 11 in the Y direction and the opposite direction. The upper surface of the placement portion 11 is a plane defined in the X direction and the Y direction, and is a placement surface on which the sheet S is placed. Further, as shown in FIG. 2 when the image forming apparatus 100 is viewed in the Y direction, the placement portion 11 is supported on a support base 13 that functions as a driving unit, and is configured to be reciprocally movable in the Z direction by the lifting drive of the support base 13.

[0015] As the sheet S, in addition to plain paper, glossy paper, special paper, etc., building materials such as wallpaper, floor materials, tiles, cloth for clothing such as T-shirts, textiles, leather, etc. are used. Further, ceramics, glass, metal, etc. may be used as the sheet S. Also, it is possible to use a non-permeable substrate as the sheet S. A non-permeable substrate is a substrate having a surface with low water permeability and absorbency, and includes materials that have a large number of cavities inside but do not open to the outside. More quantitatively, in the Bristow method, the water absorption amount from the start of contact to 30 msec1 / 2 is 10 mL / m

[0016] , , The following is the substrate referred to. Specifically, examples of non-permeable substrates include plastic films such as vinyl chloride resin films, polyethylene terephthalate (PET) films, polypropylene, polyethylene, and polycarbonate films.

[0016] The image forming unit 2 includes a carriage 21 that can reciprocate along a guide rail 23 extending in the X direction, and an ink ejection head 22 that serves as a liquid ejection head for ejecting liquid ink onto the sheet S. The ink ejection head 22 is mounted on the carriage 21 and is configured to reciprocate along the guide rail 23 in the X direction together with the carriage 21. In this case, the ink ejection head 22 consists of multiple ink ejection heads 22 that eject ink (liquid) of different colors, such as yellow, magenta, cyan, and black. The number of ink ejection heads 22 and the colors of the ink ejected can be changed as appropriate.

[0017] The pre-processing unit 3 includes a carriage 31 that can reciprocate along a guide rail 33 extending in the X direction, a pre-processing liquid discharge head 32 which serves as a liquid discharge head for discharging pre-processing liquid onto the sheet S, and a leveling roller 34 which serves as a leveling member. The pre-processing liquid discharge head 32 and the leveling roller 34 are mounted on the carriage 31 and are configured to reciprocate along the guide rail 33 in the X direction together with the carriage 31. Furthermore, the leveling roller 34 can also reciprocate in the Z direction, which is perpendicular or intersecting to the surface (image forming surface) of the sheet S, by being driven by a lifting drive unit 35 which serves as a drive unit as shown in Figure 2. Note that the leveling member is not limited to the leveling roller 34, but may be a leveling blade or the like. Also, the number of pre-processing liquid discharge heads 32 is not limited to multiple units, but may be one unit.

[0018] The image formation maintenance unit 4 is a maintenance unit for maintaining or restoring the condition of the ink ejection head 22. If the ink ejection head 22 is left unused for a long period of time, the ink remaining in the nozzle of the ink ejection head 22 may thicken due to drying, and the thickened residual ink may clog the nozzle, potentially reducing ink ejection performance. In addition, if foreign matter such as dust adheres to the nozzle surface, ink ejection performance may also be reduced. Therefore, when the ink ejection head 22 is not in use, the image formation maintenance unit 4 is used to suppress the drying of the nozzle of the ink ejection head 22 and remove foreign matter adhering to the nozzle surface of the ink ejection head 22, thereby maintaining or restoring the ejection performance of the ink ejection head 22.

[0019] The pre-processing maintenance unit 5 is a maintenance unit for maintaining or restoring the condition of the pre-processing liquid discharge head 32. In the pre-processing liquid discharge head 32, if residual liquid in the nozzle dries out or foreign matter adheres to the nozzle surface, the pre-processing liquid discharge performance deteriorates. Therefore, the pre-processing maintenance unit 5 is used to maintain or restore the discharge performance of the pre-processing liquid discharge head 32. The detailed configuration of the pre-processing maintenance unit 5 and the image forming maintenance unit 4 will be described later.

[0020] <Image Formation Process> Next, the image forming operation of the image forming apparatus 100 according to the first embodiment of the present invention will be described.

[0021] As shown in Figure 1, with the sheet S placed on the mounting unit 11, when the mounting unit 11 moves in the direction of arrow A from the position indicated by the dashed line in the figure, the sheet S is transported toward the pre-processing unit 3.

[0022] The sheet S is transported to the pre-processing unit 3, and when the leading edge of the sheet S reaches the movement range of the pre-processing unit 3, the transport of the sheet S is temporarily stopped. Then, the sheet S undergoes a leveling process by the leveling roller 34 and a pre-processing liquid application process by the pre-processing liquid discharge head 32.

[0023] Specifically, first, as shown in Figure 2, the leveling roller 34 descends and comes into contact with the surface (top surface) of the sheet S. Next, with the leveling roller 34 in contact with the sheet S, the carriage 31 moves back and forth along the guide rail 33. As a result, the leveling roller 34 rotates and moves back and forth while in contact with the surface (top surface) of the sheet S. At this time, the surface of the sheet S is pressed by the reciprocating leveling roller 34, which suppresses fuzzing and other issues on the surface of the sheet S, and the surface of the sheet S is leveled.

[0024] Next, as shown in Figure 3, the leveling roller 34 rises and moves to a retracted position where it is moved away from the surface of the sheet S. With the leveling roller 34 in the retracted position, the carriage 31 moves back and forth along the guide rail 33, and the pretreatment liquid is discharged from the pretreatment liquid discharge head 32 toward the sheet S. This applies the pretreatment liquid to the leveled surface of the sheet S.

[0025] After the pre-treatment process, which includes the leveling process and the pre-treatment liquid application process described above, is completed, the movement of the mounting section 11 is resumed, and the sheet S is transported toward the image forming unit 2. When the leading edge of the sheet S reaches the movement range of the image forming unit 2, the transport of the sheet S is temporarily stopped again, and the image forming process is performed by the image forming unit 2. Specifically, the carriage 21, which is equipped with the ink ejection head 22, moves back and forth along the guide rail 23, and ink is ejected from the ink ejection head 22 onto the sheet S. As a result, ink is applied to the surface of the sheet S and an image is formed. The image formed on the sheet S may be an image with meaning, such as characters and figures, or an image without meaning, such as a pattern.

[0026] Furthermore, as described above, when the leading edge of the sheet S reaches the movement range of the image forming unit 2 as the sheet S is transported, another portion of the sheet S that has not yet undergone pre-processing reaches the pre-processing unit 3, which is upstream of the image forming unit 2 in the sheet transport direction A. Therefore, in the pre-processing unit 3, when the image forming process is performed by the image forming unit 2, the same pre-processing steps (leveling step and pre-processing liquid application step) as described above are performed on the newly reached portion of the sheet S.

[0027] Similarly, the sheet S is transported intermittently, and the pre-processing step by the pre-processing unit 3 and the image forming step by the image forming unit 2 are repeated. As a result, the leveling step and the pre-processing solution application step are performed over the entire image forming area of ​​the sheet S, and an image is formed in the image forming area of ​​the sheet S that has undergone the leveling step and the pre-processing solution application step.

[0028] Subsequently, the mounting unit 11 is moved to a predetermined home position, and the sheet S is removed from the mounting unit 11, thereby obtaining a sheet S on which the desired image has been formed.

[0029] As described above, in the image forming apparatus 100 according to the first embodiment of the present invention, the quality of the image formed on the sheet S can be improved by performing a leveling process on the sheet S before the image is formed. That is, since the pretreatment liquid and ink are sequentially applied to the flat surface of the sheet S after the leveling process, the pretreatment liquid and ink can be applied uniformly to the surface of the sheet S, and color unevenness, bleeding, etc. can be suppressed.

[0030] Furthermore, as in the first embodiment of the present invention, when the image forming unit 2 performs the image forming configuration, the pre-processing steps (leveling steps, or both leveling steps and pre-processing solution application steps) are performed simultaneously on the new portion that reaches the movement range of the pre-processing unit 3, thereby shortening the processing time compared to when these steps are performed at different times.

[0031] Furthermore, the leveling process is not limited to being performed before the pretreatment liquid application process, but may also be performed after the pretreatment liquid application process. In that case, as in the configuration of the first embodiment of the present invention, the leveling roller 34 is provided on the carriage 31 having the pretreatment liquid discharge head 32, so that the leveling process can be performed quickly after the pretreatment liquid is applied to the sheet S and before the pretreatment liquid on the sheet S dries.

[0032] Furthermore, as shown in Figure 4, the image forming apparatus 100 may be equipped with a height detection sensor 6 that detects the height of the image forming surface (top surface) of the sheet S. The height detection sensor 6 is, for example, a pair of optical sensors 61 and 62, which are arranged at both ends of the mounting section 11 so as to sandwich the sheet S. Since the mounting section 11 is configured to be able to move up and down in the Z direction, as the mounting section 11 moves up and down, the height of the object to be detected on the mounting section 11 is detected as the object passes between the optical sensors. For example, as shown in Figure 5, when a protrusion 8 on the sheet S reaches the detection position 60 of the height detection sensor 6, or as shown in Figure 6, when the image forming surface of the sheet S reaches the detection position 60 of the height detection sensor 6, the height detection sensor 6 detects the height of the protrusion 8 or the height of the image forming surface. The height information detected by the height detection sensor 6 is stored in the storage unit 7.

[0033] Alternatively, as shown in Figure 7, a distance sensor 63 that detects the distance to an object may be used as the height detection sensor 6. In this case, the height detection sensor 6 (distance sensor 63) is provided on the carriage 31 and detects the height (distance) of the image forming surface or protrusion 8 of the sheet S while the carriage 31 is moving.

[0034] In the image forming apparatus 100 equipped with the height detection sensor 6 described above, the presence or absence of protrusions 8 on the sheet S can be determined from the detected height information, so as shown in Figure 8, the leveling roller 34 can move while avoiding the protrusions 8 on the sheet S. In this case, when the leveling roller 34 reaches the position just before the protrusions 8, the leveling roller 34 is raised to avoid contact with the protrusions 8, and when the leveling roller 34 has passed the protrusions 8, the leveling roller 34 is lowered to make contact with the sheet S. This makes it possible to perform the leveling process on parts of the sheet S other than the protrusions 8, and to suppress fuzzing and other issues.

[0035] <Maintenance Unit Configuration> Next, the configurations of the image forming maintenance unit 4 and the pre-processing maintenance unit 5 according to the first embodiment of the present invention will be described. Since the image forming maintenance unit 4 and the pre-processing maintenance unit 5 according to the first embodiment of the present invention have the same basic configuration, in the following description, the image forming maintenance unit 4 and the pre-processing maintenance unit 5 will be collectively referred to as "maintenance units 4 and 5," and their basic configurations will be described accordingly. In addition, the ink ejection head 22 and the pre-processing liquid ejection head 32, which are the targets of maintenance, will be collectively referred to as "ejection heads 22 and 32" in the description.

[0036] Figure 9 is a schematic diagram showing the basic configuration of maintenance units 4 and 5 according to the first embodiment of the present invention.

[0037] As shown in Figure 9, the maintenance units 4 and 5 according to the first embodiment of the present invention include a cap member 71 that covers the nozzle surfaces 22n and 32n of the discharge heads 22 and 32, and a cleaning device 9 that cleans the nozzle surfaces 22n and 32n of the discharge heads 22 and 32.

[0038] The cap member 71 is a component that covers the nozzle surfaces 22n and 32n of the discharge heads 22 and 32 to provide moisture retention and suction to the nozzles. When the discharge heads 22 and 32 are not in use, they are moved to a home position facing the cap member 71, and capping is performed by the cap member 71. That is, as the cap member 71 approaches the nozzle surfaces 22n and 32n of the discharge heads 22 and 32 that have moved to the home position, the nozzle surfaces 22n and 32n are covered by the cap member 71. This suppresses the drying of liquid (ink) remaining on the nozzle surfaces 22n and 32n and the liquid (ink) inside the nozzles, thereby preventing nozzle clogging due to drying and solidification of residual liquid. In addition, it prevents foreign matter from adhering to the nozzle surfaces 22n and 32n, so that the discharge performance of the discharge heads 22 and 32 can be maintained.

[0039] Furthermore, the cap member 71 is connected to the suction pump 220, which is a suction means, via the flexible tube 219. By driving the suction pump 220 with the nozzle surfaces 22n and 32n capped by the cap member 71, the nozzle is sucked, and any liquid remaining in the nozzle is sucked out and removed. This prevents the residual liquid from solidifying inside the nozzle. The sucked-out liquid is discharged to the waste liquid tank 301 via the flexible tube 219.

[0040] The cleaning device 9 includes a wiping member 73 for wiping the nozzle surfaces 22n and 32n of the discharge heads 22 and 32.

[0041] The wiping member 73 is configured to move in a direction perpendicular to or intersecting the direction of movement of the discharge heads 22 and 32. When wiping the nozzle surfaces 22n and 32n with the wiping member 73, the wiping member 73 is first moved to a nozzle surface wiping position (height) where it can contact the nozzle surfaces 22n and 32n. In this state, the carriages 21 and 31 are moved to move the discharge heads 22 and 32 to a position facing the wiping member 73. When the discharge heads 22 and 32 reach the position facing the wiping member 73, the wiping member 73 comes into contact with the nozzle surfaces 22n and 32n, and as the discharge heads 22 and 32 move further, the wiping member 73 slides along the nozzle surfaces 22n and 32n. As a result, the nozzle surfaces 22n and 32n are wiped, and residual liquid and foreign matter adhering to the nozzle surfaces 22n and 32n are removed. Any residual liquid removed by the wiping member 73 is collected by a collection container 302 located below the wiping member 73.

[0042] In addition to the wiping member 73, the cleaning device 9 also includes a cleaning liquid application means 74 for applying cleaning liquid to the wiping member 73, and a scraper 75 for removing liquid and other substances adhering to the wiping member 73.

[0043] If foreign matter such as residual liquid removed by the wiping operation adheres to the wiping member 73, there is a risk that this foreign matter may adhere from the wiping member 73 to the nozzle surfaces 22n and 32n during subsequent wiping operations. Therefore, if foreign matter is attached to the wiping member 73, the scraper 75 can be pressed against the wiping member 73, and the wiping member 73 can be moved in that state to remove the foreign matter attached to the wiping member 73. By removing the foreign matter attached to the wiping member 73 in this way, the adhesion of residual liquid from the wiping member 73 to the nozzle surfaces 22n and 32n can be prevented, improving cleanability.

[0044] Furthermore, if the wiping member 73 is dirty, cleaning fluid may be applied to the wiping member 73 by the cleaning fluid application means 74. The cleaning fluid application means 74 is connected to the cleaning fluid supply pump 213 and the cleaning fluid storage tank 215 via the cleaning fluid supply tube 214, and is configured to supply cleaning fluid 216 from the cleaning fluid storage tank 215 when the cleaning fluid supply pump 213 is driven. In addition, a filter 92 is provided upstream of the cleaning fluid supply pump 213, and a check valve 91 is provided downstream of the cleaning fluid supply pump 213. The discharge pressure of the cleaning fluid supply pump 213 is controlled based on the pressure detected by the pressure sensor 93.

[0045] When cleaning the wiping member 73, the wiping member 73 is moved to a position facing the cleaning liquid nozzle 74a of the cleaning liquid supply means 74. Then, the cleaning liquid supply pump 213 is driven to supply cleaning liquid 216 from the cleaning liquid storage tank 215 to the cleaning liquid supply means 74. As a result, the cleaning liquid 216 is sprayed from the cleaning liquid nozzle 74a toward the wiping member 73, and the cleaning liquid 216 is applied to the wiping member 73. In this way, by applying the cleaning liquid 216 to the wiping member 73, the dirt on the wiping member 73 is washed away, and the wiping function of the wiping member 73 can be restored. The cleaning liquid that flows out of the wiping member 73 is collected by the recovery container 302. The collection container 302 is equipped with a liquid level detection sensor 94 that detects the liquid level of the collected cleaning liquid. When the liquid level detection sensor 94 detects the liquid level of the cleaning liquid, the waste liquid pump 218 is activated, and the cleaning liquid in the collection container 302 is discharged to the waste liquid tank 301 through the cleaning liquid waste tube 217.

[0046] The cleaning solution 216 is preferably a liquid containing a solvent with extremely low volatility (also called a wet solution), such as glycerin or polyethylene glycol. The solvent can be selected from well-known organic solvents depending on the purpose. The cleaning solution 216 may also consist only of a solvent, or only of water (purified water, high-purity water, etc.). Furthermore, the cleaning solution 216 may contain any surfactant. If the cleaning solution 216 contains a surfactant, the surface tension on the nozzle surface can be adjusted, improving the cleaning effect.

[0047] <Configuration of the control unit> Figure 10 is a block diagram showing the configuration of the control unit 500 included in the image forming apparatus 100 according to the first embodiment of the present invention.

[0048] As shown in Figure 10, the image forming apparatus 100 according to the first embodiment of the present invention includes a control unit 500 that controls the overall operation of the image forming apparatus 100.

[0049] The control unit 500 includes a CPU (Central Processing Unit) 501, ROM (Read Only Memory) 502, RAM (Random Access Memory) 503, NVRAM (Non-Volatile Random Access Memory) 504, an external device connection interface 505, a network interface 506, a bus line 507, and the like.

[0050] The CPU 501 controls the overall operation of the image forming apparatus 100. The ROM 502 stores programs used to drive the CPU 501, such as IPL. The RAM 503 is used as the work area for the CPU 501. The NVRAM 504 stores various data, such as programs, and can retain various data even when the power to the image forming apparatus 100 is cut off.

[0051] The external device connection interface 505 is connected to a PC (Personal Computer) via a USB (Universal Serial Bus) cable, etc., and communicates control signals and image data with the PC. The network interface 506 is an interface for data communication using a communication network such as the Internet. The bus line 507 is an address bus and data bus for electrically connecting various components such as the CPU 501.

[0052] Furthermore, the control unit 500 includes a main scanning driver 508, an ejection head driver 509, a leveling roller driver 510, and a maintenance unit driver 511.

[0053] The main scanning driver 508 controls the movement of the carriages 21 and 31 in the main scanning direction (reciprocating movement in the X direction). The discharge head driver 509 is a driver for controlling the discharge operation of the discharge heads 22 and 32. The leveling roller driver 510 controls the lifting and lowering operation of the leveling roller 34 (reciprocating movement in the Z direction) and the rotational drive of the leveling roller 34. The maintenance unit driver 511 controls the driving of the wiping member 73, the cleaning fluid supply pump 213, and the suction pump 220, which are provided in the maintenance units 4 and 5.

[0054] Furthermore, the control unit 500 is configured to acquire information input by the operation panel 600, time information counted by the elapsed time counting unit 601, and main scan count information counted by the main scan counting unit 602.

[0055] The control panel 600 is an input unit, such as a touch panel, provided on the main body of the image forming apparatus. When the user operates the control panel 600 to input printing conditions such as image information, the control unit 500 generates an image forming signal according to the input printing conditions, and the ejection head driver 509 controls the ink ejection head 22 based on the generated image forming signal. As a result, the desired image is formed on the sheet.

[0056] The elapsed time counting unit 601 counts the elapsed time starting from a predetermined timing. The control unit 500 manages the timing of maintenance operations by the maintenance units 4 and 5 based on the time counted by the elapsed time counting unit 601.

[0057] The main scan count unit 602 counts the number of times the carriages 21 and 32 move in the main scan direction. The control unit 500 manages the timing of maintenance operations by the maintenance units 4 and 5 based on the counts recorded by the main scan count unit 602.

[0058] <Challenges related to cleaning leveling rollers> However, in a configuration such as the first embodiment of the present invention, which includes a leveling roller 34 for leveling the surface of the sheet S, foreign matter such as fibers from the sheet S, dust, and pre-treatment liquid may adhere to the surface of the leveling roller 34 when the leveling process is performed. If the next leveling process is performed with foreign matter adhering to the surface of the leveling roller 34, the foreign matter on the leveling roller 34 may adhere to the sheet S, potentially degrading the quality of the image formed on the sheet S.

[0059] Therefore, it is necessary to clean the leveling roller 34 to prevent foreign matter from remaining attached to its surface. However, adding a dedicated cleaning device for cleaning the leveling roller 34 presents challenges such as increasing the overall size and cost of the equipment.

[0060] Therefore, in order to solve the above problems, the first embodiment of the present invention proposes the following configuration of a cleaning device. The configuration of the cleaning device according to the first embodiment of the present invention will be described below.

[0061] <Configuration of the cleaning device> Figures 11 and 12 show the configuration and cleaning operation of the pre-treatment maintenance unit 5 according to the first embodiment of the present invention.

[0062] As shown in Figures 11 and 12, the cleaning device 9 of the pre-treatment maintenance unit 5 includes a wiping member 73 that wipes the nozzle surface 32n of the pre-treatment liquid discharge head 32, and a cleaning liquid application means 74 that applies cleaning liquid to the wiping member 73.

[0063] Furthermore, the cleaning device 9 includes a wiping member drive unit 76 that reciprocates the wiping member 73 in the Z direction. As a result, the wiping member 73 is configured to move between a cleaning position (shown in Figure 11) facing the cleaning liquid nozzle 74a of the cleaning liquid application means 74 and a retracted position (shown in Figure 12) that is moved away from the cleaning position.

[0064] Here, the cleaning device 9 is configured to clean the nozzle surface 32n of the pretreatment liquid discharge head 32, as well as the surface of the leveling roller 34. In the first embodiment of the present invention, the cleaning device 9 applies the cleaning liquid 216 to the leveling roller 34 using the cleaning liquid application means 74. For this reason, the leveling roller 34 is configured to be movable from the retracted position shown in Figure 11 to a cleaning position (the position shown in Figure 12) facing the cleaning liquid nozzle 74a of the cleaning liquid application means 74 by the drive of the lifting drive unit 35.

[0065] <Cleaning operation> Next, referring to the flowchart in Figure 13, the operation of the pre-treatment maintenance unit 5 (cleaning device 9) when cleaning the leveling roller 34 in the first embodiment of the present invention will be described.

[0066] When the cleaning operation begins, first the carriage 31, which is equipped with the leveling roller 34, starts moving along the guide rail 33, moving the leveling roller 34 to a predetermined position for cleaning (Step 1 in Figure 13). When the carriage 31 has moved to the predetermined position, as shown in Figure 11, the leveling roller 34 is positioned in a retracted position, away from the cleaning liquid nozzle 74a of the cleaning liquid application means 74. To clean the leveling roller 34, it is necessary to lower the leveling roller 34 and move it to a cleaning position facing the cleaning liquid nozzle 74a. However, if the wiping member 73 is in a cleaning position facing the cleaning liquid nozzle 74a (see Figure 11), then, as shown in Figure 12, the wiping member 73 is lowered and moved to a retracted position that does not face the cleaning liquid nozzle 74a (Step 2 in Figure 13). Next, as shown in Figure 12, the leveling roller 34 is lowered and moved to the cleaning position (Step 3 in Figure 13).

[0067] Subsequently, the cleaning liquid 216 is sprayed from the cleaning liquid nozzle 74a of the cleaning liquid application means 74 to begin applying the cleaning liquid 216 to the leveling roller 34 (Step 4 in Figure 13). At this time, by rotating the leveling roller 34 while applying the cleaning liquid 216 to it (Step 5 in Figure 13), the cleaning liquid 216 is applied to the entire surface in the direction of rotation of the leveling roller 34, so that foreign matter adhering to the surface of the leveling roller 34 can be effectively washed away. Alternatively, the leveling roller 34 may be controlled not to rotate while the cleaning liquid 216 is being applied to it.

[0068] Then, the cleaning solution 216 is applied to the leveling roller 34 for a predetermined time, and after the predetermined time has elapsed (Step 6 in Figure 13), the application of the cleaning solution 216 is stopped (Step 7 in Figure 13). At this point, the rotation of the leveling roller 34 may be stopped at the same time as the application of the cleaning solution 216 is stopped, but in the first embodiment of the present invention, the rotation of the leveling roller 34 is continued for a predetermined time even after the application of the cleaning solution 216 is stopped, and after the predetermined time has elapsed (Step 8 in Figure 13), the rotation of the leveling roller 34 is stopped (Step 9 in Figure 13). In this way, by continuing to rotate the leveling roller 34 for a predetermined time even after the application of the cleaning solution 216 is stopped, excess cleaning solution 216 adhering to the leveling roller 34 can be removed. This prevents excess cleaning solution 216 on the leveling roller 34 from adhering to the sheet S during the subsequent leveling process. Furthermore, the timing for stopping the rotation of the leveling roller 34 may be determined by counting the rotation time of the leveling roller 34, or by counting the number of rotations of the leveling roller 34.

[0069] After stopping the spraying of the cleaning solution 216 and the rotation of the leveling roller 34, the leveling roller 34 is raised and moved to the retracted position shown in Figure 11 (Step 10 in Figure 13). This completes the series of cleaning operations.

[0070] As described above, in the first embodiment of the present invention, by cleaning the leveling roller 34 using the cleaning device 9 mounted on the pre-processing maintenance unit 5, foreign matter adhering to the surface of the leveling roller 34 can be removed without the user having to clean it manually. This reduces the workload for the user and other personnel, and also maintains a clean surface condition for the leveling roller 34, thereby preventing a decrease in image quality due to foreign matter adhering from the leveling roller 34 to the sheet S.

[0071] Furthermore, according to the first embodiment of the present invention, by using the cleaning device 9 that cleans the pretreatment liquid discharge head 32 to clean the leveling roller 34, the overall size and cost of the device can be reduced. In other words, by using the existing cleaning device 9 that cleans the pretreatment liquid discharge head 32 as a shared cleaning device that cleans both the pretreatment liquid discharge head 32 and the leveling roller 34, it becomes unnecessary to add a dedicated cleaning device for cleaning the leveling roller 34, thus avoiding an increase in the size and cost of the overall cleaning device.

[0072] Next, other embodiments of the present invention will be described. In the following description, we will mainly describe parts that differ from the first embodiment of the present invention, and descriptions of the same parts will be omitted as appropriate.

[0073] <Second Embodiment of the Present Invention> Figure 14 shows the configuration and cleaning operation of the pre-treatment maintenance unit 5 according to the second embodiment of the present invention.

[0074] As shown in Figure 14, in the second embodiment of the present invention, when the cleaning liquid application means 74 applies the cleaning liquid 216 to the leveling roller 34, the wiping member 73 is further brought into contact with the leveling roller 34. Otherwise, it is basically the same as the first embodiment of the present invention.

[0075] Thus, in the second embodiment of the present invention, when the cleaning liquid application means 74 applies the cleaning liquid 216 to the leveling roller 34, the wiping member 73 is brought into contact with the leveling roller 34, and the cleaning liquid 216 is applied while the leveling roller 34 is rotated in this state. This allows foreign matter adhering to the surface of the leveling roller 34 to be scraped off by the wiping member 73 and washed away by the cleaning liquid 216. As a result, foreign matter adhering to the surface of the leveling roller 34 can be removed more effectively.

[0076] Figure 15 is a flowchart showing the cleaning operation of the pre-treatment maintenance unit 5 according to the second embodiment of the present invention.

[0077] In this case, when the cleaning operation is started, the carriage 31 moves to move the leveling roller 34 to a predetermined cleaning position, just as in the first embodiment of the present invention described above (Step 1 in Figure 15). Next, the wiping member 73 is moved to a retracted position that does not face the cleaning liquid nozzle 74a (Step 2 in Figure 15), and the leveling roller 34 is lowered to move to a cleaning position that faces the cleaning liquid nozzle 74a (Step 3 in Figure 15).

[0078] Then, the wiping member 73 is raised and moved to a wiping position where it contacts the surface of the leveling roller 34, as shown in Figure 14 (Step 4 in Figure 15).

[0079] Subsequently, the cleaning liquid 216 is applied from the cleaning liquid application means 74 to the leveling roller 34 (Step 5 in Figure 15), and the rotation of the leveling roller 34 is started (Step 6 in Figure 15). As a result, the cleaning liquid 216 is applied while the leveling roller 34 rotates, with the wiping member 73 in contact with the leveling roller 34. This wipes the surface of the leveling roller 34, effectively removing any foreign matter adhering to its surface.

[0080] Then, after a predetermined time has elapsed (Step 7 in Figure 15), the application of the cleaning liquid 216 is stopped (Step 8 in Figure 15). In the second embodiment of the present invention, as in the first embodiment, the rotation of the leveling roller 34 is stopped after a predetermined time has elapsed after the application of the cleaning liquid 216 has stopped (Step 9 in Figure 15) (Step 10 in Figure 15), thereby removing excess cleaning liquid 216 adhering to the leveling roller 34. In the second embodiment of the present invention, after the application of the cleaning liquid 216 is stopped, the wiping member 73 is in contact with the surface of the leveling roller 34, and the leveling roller 34 continues to rotate for a predetermined time, so that excess cleaning liquid 216 adhering to the leveling roller 34 is effectively removed by the wiping member 73. This makes it possible to more reliably prevent excess cleaning liquid 216 on the leveling roller 34 from adhering to the sheet S.

[0081] Subsequently, the wiping member 73 is moved to a retracted position where it does not come into contact with the leveling roller 34 (Step 11 in Figure 15), and the leveling roller 34 is raised to a retracted position where it does not face the cleaning liquid nozzle 74a (Step 12 in Figure 15). This completes the cleaning operation in the second embodiment of the present invention.

[0082] Figure 16 shows the positional relationship between the cleaning fluid application position B on the leveling roller 34 and the contact position C where the wiping member 73 makes contact.

[0083] As shown in Figure 16, the cleaning fluid application position B, where the cleaning fluid 216 is applied to the leveling roller 34 from the cleaning fluid application means 74, is preferably higher than the contact position C where the wiping member 73 contacts the leveling roller 34, i.e., higher in the direction of gravity.

[0084] Thus, because the cleaning liquid application position B is higher than the contact position C of the wiping member 73, when the cleaning liquid 216 is applied to the leveling roller 34, the cleaning liquid 216 flows down along the surface of the leveling roller 34 to the contact position C of the wiping member 73, allowing the foreign matter removed by the wiping member 73 to be washed away by the cleaning liquid 216. This effectively removes the foreign matter 10 on the leveling roller 34.

[0085] Furthermore, as shown in Figure 16, it is preferable that the cleaning fluid application position B is located upstream of the contact position C of the wiping member 73 in the rotational direction of the leveling roller 34. More specifically, as shown in Figure 16, it is preferable that the cleaning fluid application position B is located upstream or above the contact position C of the wiping member 73 in the rotational direction of the leveling roller 34 within the range H from the uppermost position 34a on the surface of the leveling roller 34 to the lowermost position 34b on the downstream side in the rotational direction.

[0086] In this way, by positioning the cleaning fluid application position B upstream of the leveling roller 34 in the direction of rotation from the contact position C of the wiping member 73, the cleaning fluid 216 applied to the leveling roller 34 can easily move to the contact position C of the wiping member 73, which is downstream in the direction of rotation, as the leveling roller 34 rotates. As a result, foreign matter removed by the wiping member 73 can be more reliably washed away by the cleaning fluid 216.

[0087] <Third Embodiment of the Invention> Figure 17 is a flowchart showing the cleaning operation of the pre-treatment maintenance unit 5 according to the third embodiment of the present invention. Figure 18 is a diagram showing the configuration and cleaning operation of the pre-treatment maintenance unit 5 according to the third embodiment of the present invention.

[0088] In the third embodiment of the present invention, Steps 1 to 10 in Figure 17 are the same as Steps 1 to 10 in Figure 15 in the second embodiment of the present invention. Therefore, in the third embodiment of the present invention, as in the second embodiment of the present invention, the leveling roller 34 can be effectively cleaned by applying the cleaning liquid 216 while bringing the wiping member 73 into contact with the rotating leveling roller 34 (see Figure 14).

[0089] Subsequently, when the rotation of the leveling roller 34 is stopped (Step 10 in Figure 17), in the third embodiment of the present invention, as shown in Figure 18, the leveling roller 34 is raised and moved to a retracted position that does not face the cleaning liquid nozzle 74a (Step 11 in Figure 17). Next, the wiping member 73 is raised and moved to a cleaning position that faces the cleaning liquid nozzle 74a (Step 12 in Figure 17).

[0090] Then, with the wiping member 73 in the cleaning position, the cleaning liquid 216 is sprayed from the cleaning liquid nozzle 74a toward the wiping member 73, applying the cleaning liquid 216 to the wiping member 73 (Step 13 in Figure 17). After that, the application of the cleaning liquid 216 is stopped (Step 14 in Figure 17), and the wiping member 73 is moved to a retracted position that does not face the cleaning liquid nozzle 74a (Step 15 in Figure 17), thereby completing the cleaning operation.

[0091] Thus, in the third embodiment of the present invention, by cleaning the wiping member 73 after cleaning the leveling roller 34, foreign matter adhering to the wiping member 73 can be removed. This prevents foreign matter from adhering from the wiping member 73 to the nozzle surface 32n, and enables effective cleaning of the nozzle surface 32n.

[0092] <Timing for cleaning the leveling roller> Next, we will explain the cleaning timing for the leveling roller 34.

[0093] The cleaning timing for the leveling roller 34 may be different from the cleaning timing for the nozzle surface 32n of the pretreatment liquid discharge head 32. For example, the number of times the leveling process has been performed may be counted, and when that number reaches a predetermined number, the cleaning device 9 may perform a cleaning operation on the leveling roller 34.

[0094] Figure 19 is a flowchart showing an example of the cleaning timing for cleaning the leveling roller 34.

[0095] In the example shown in Figure 19, once the image forming operation is started (Step 1 in Figure 19), the number of times the leveling process has been performed is counted (Step 2 in Figure 19). The number of times the leveling process has been performed can be determined, for example, by counting the number of times the carriage 31 moves in the main scanning direction during the leveling process using the main scan count unit 602 in Figure 10. The information counted by the main scan count unit 602 is stored in a storage unit such as the ROM 502 of the control unit 500.

[0096] Then, after the image forming operation is completed (Step 3 in Figure 19), if the counted number of leveling steps has reached a predetermined number (if "YES" is shown in Step 4 in Figure 19), the cleaning device 9 performs a cleaning operation on the leveling roller 34 (Step 5 in Figure 19). On the other hand, if the counted number of leveling steps has not reached a predetermined number (if "NO" is shown in Step 4 in Figure 19), the cleaning operation on the leveling roller 34 by the cleaning device 9 is not performed and the process ends (Step 6 in Figure 19).

[0097] In this way, by determining whether or not to clean the leveling roller 34 based on the counted number of leveling processes, cleaning can be performed at the necessary timing, thus avoiding unnecessary cleaning operations and reducing unnecessary consumption of cleaning fluid and wear and tear on parts.

[0098] Furthermore, the decision of whether or not to clean the leveling roller 34 may be made based on the number of times the leveling process has been performed, as well as the elapsed time since the last cleaning. The elapsed time since the last cleaning is counted, for example, by the elapsed time counting unit 601 in Figure 10, and the counted time information is stored in a storage unit such as the ROM 502. In this case as well, the leveling roller 34 can be cleaned at the necessary timing, reducing the consumption of unnecessary cleaning fluid and wear and tear on parts.

[0099] Furthermore, the cleaning operation by the cleaning device 9 may be changed depending on the number of counted leveling steps or the counted elapsed time. For example, at one cleaning timing, a cleaning operation may be performed by applying only the cleaning fluid 216 as shown in Figure 12, while at another cleaning timing, a cleaning operation may be performed that includes both applying the cleaning fluid 216 and wiping with the wiping member 73 as shown in Figure 14. While a cleaning operation that includes both applying the cleaning fluid and wiping can clean the leveling roller 34 more effectively than a cleaning operation that includes only applying the cleaning fluid, there is a concern that it may accelerate wear due to contact (sliding) between the wiping member 73 and the leveling roller 34. For this reason, by selectively performing a cleaning operation that includes both applying the cleaning fluid and wiping at the necessary timing depending on the number of counted leveling steps or the counted elapsed time, wear due to contact between the wiping member 73 and the leveling roller 34 can be suppressed.

[0100] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and the design can be modified as appropriate without departing from the spirit of the invention.

[0101] For example, the cleaning device for cleaning the leveling roller may be a cleaning device that cleans the pretreatment liquid discharge head that discharges the pretreatment liquid, or a cleaning device that cleans the discharge head that discharges liquids other than the pretreatment liquid.

[0102] Furthermore, the rollers cleaned by the cleaning device according to the present invention may be leveling rollers, or rollers that come into contact with the surface of the sheet for purposes other than leveling.

[0103] Furthermore, the liquid ejection device according to the present invention may be an image forming device that ejects ink onto a sheet to form an image, or it may be a device that ejects liquid onto a sheet for purposes other than image formation. For example, the liquid ejection device according to the present invention may be a device that ejects liquids such as solutions, suspensions, and emulsions containing water, solvents such as organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functional materials such as surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium, and edible materials such as natural pigments. These liquids are used not only for inkjet inks, but also for surface treatment liquids, components of electronic elements and light-emitting elements, liquids for forming electronic circuit resist patterns, and material liquids for 3D molding.

[0104] Furthermore, the liquid dispensing device according to the present invention may include means for feeding, conveying, and dispensing sheets, as well as a pre-treatment device and the like.

[0105] To summarize the embodiments of the present invention described above, the present invention includes at least the following embodiments.

[0106] [First aspect] The first embodiment is a cleaning device that cleans both a liquid dispensing head that dispenses liquid onto a sheet and a roller that moves while in contact with the surface of the sheet.

[0107] [Second aspect] The second embodiment is a cleaning device comprising, in the first embodiment, a wiping member for wiping the nozzle surface of the liquid discharge head, and a cleaning liquid application means for applying cleaning liquid to the wiping member and the roller.

[0108] [Third aspect] A third embodiment is the second embodiment, wherein the cleaning fluid dispensing means dispenses the cleaning fluid to the roller while the roller is rotating.

[0109] [Fourth aspect] A fourth embodiment is that, in the second or third embodiment, the wiping member is movable between a nozzle surface wiping position for wiping the nozzle surface and a cleaning position for which cleaning liquid is applied by the cleaning liquid application means.

[0110] [Fifth aspect] The fifth embodiment is one of the second to fourth embodiments in which, while the roller is rotating, the wiping member comes into contact with the roller and the cleaning fluid dispensing means dispenses cleaning fluid.

[0111] [Sixth aspect] In the sixth embodiment, in the fifth embodiment, the position at which the cleaning liquid is applied to the roller from the cleaning liquid application means is higher than the position at which the wiping member contacts the roller.

[0112] [Seventh aspect] The seventh embodiment is that, in the fifth or sixth embodiment, the position at which the cleaning liquid is applied to the roller from the cleaning liquid application means is upstream of the position at which the wiping member contacts the roller in the direction of rotation of the roller.

[0113] [Eighth aspect] The eighth aspect is, in the third aspect, after stopping the application of cleaning fluid from the cleaning fluid application means to the roller, the rotation of the roller is continued for a predetermined time and then stopped.

[0114] [Ninth aspect] The ninth embodiment is one of the second to eighth embodiments in which the wiping member comes into contact with the roller and the cleaning liquid dispensing means dispenses cleaning liquid, and then the cleaning liquid dispensing means dispenses cleaning liquid to the wiping member.

[0115] [Tenth aspect] In the tenth embodiment, in any one of the first to ninth embodiments, the roller is movable in a direction intersecting the surface of the sheet.

[0116] [The 11th aspect] The eleventh embodiment is a liquid dispensing device comprising a liquid dispensing head for dispensing liquid onto a sheet, a roller that moves while in contact with the surface of the sheet, and a cleaning device of any one of the first to tenth embodiments for cleaning both the liquid dispensing head and the roller. [Explanation of symbols]

[0117] 9 Cleaning equipment 32 Pre-treatment liquid dispensing head (liquid dispensing head) 32n nozzle surface 34. Leveling roller (roller) 73 Wiping material 74 Washing solution dispensing means 100 Image forming device (liquid ejection device) S Seat [Prior art documents] [Patent Documents]

[0118] [Patent Document 1] Japanese Patent Publication No. 2019-25668

Claims

1. A cleaning device characterized by cleaning both a liquid dispensing head that dispenses liquid onto a sheet and a roller that moves while in contact with the surface of the sheet.

2. A wiping member for wiping the nozzle surface of the liquid discharge head, A cleaning liquid application means for applying cleaning liquid to the wiping member and the roller, The cleaning device according to claim 1, comprising:

3. The cleaning apparatus according to claim 2, wherein the cleaning liquid application means applies cleaning liquid to the roller while the roller is rotating.

4. The cleaning device according to claim 2, wherein the wiping member is movable between a nozzle surface wiping position for wiping the nozzle surface and a cleaning position for which cleaning liquid is applied by the cleaning liquid application means.

5. The cleaning device according to claim 2, wherein the wiping member contacts the roller while the roller is rotating and the cleaning liquid application means applies cleaning liquid.

6. The cleaning device according to claim 5, wherein the position at which the cleaning liquid is applied to the roller from the cleaning liquid application means is higher than the position at which the wiping member contacts the roller.

7. The cleaning device according to claim 5, wherein the position at which the cleaning liquid is applied to the roller from the cleaning liquid application means is upstream in the rotational direction of the roller from the position at which the wiping member contacts the roller.

8. The cleaning device according to claim 3, wherein, after stopping the application of cleaning fluid from the cleaning fluid application means to the roller, the rotation of the roller is continued for a predetermined time and then stopped.

9. After the wiping member comes into contact with the roller and the cleaning liquid dispensing means dispenses the cleaning liquid, The cleaning apparatus according to claim 2, wherein the cleaning liquid application means applies cleaning liquid to the wiping member.

10. The cleaning device according to claim 1, wherein the roller is movable in a direction intersecting the surface of the sheet.

11. A liquid dispensing head that dispenses liquid onto the sheet, A roller that moves while in contact with the surface of the sheet, A cleaning device according to claim 1, which cleans both the liquid discharge head and the roller, A liquid dispensing device characterized by comprising the following features.

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