JP7624868B2 - Wiper Cleaning Device - Google Patents

Description

The present invention relates to a wiper cleaning device having a cleaning liquid tank that stores cleaning liquid for cleaning the wipers.

Conventionally, inkjet printing devices have been proposed that print by ejecting ink from an inkjet head onto print media such as paper and film.

In inkjet printing devices, ink can stick to the ink ejection openings of the nozzles, or dirt such as paper dust from the paper can adhere to them. If ink sticks to the ink ejection openings of the nozzles or paper dust accumulates, ejection problems such as misalignment of the ink ejection direction from the nozzles or failure to eject ink can occur.

To reduce such ejection defects, a series of operations is known in which ink is forcibly ejected from the nozzles of the inkjet head, a process known as purging, and then the ink ejection openings of the nozzles are wiped with a wiper.

For example, Patent Document 1 proposes an inkjet printing device in which a wiper is immersed in a cleaning liquid tank that stores cleaning liquid, and then the wiper is used to wipe the inkjet head. As described in Patent Document 1, dirt on the wiper can be removed by immersing the wiper directly in the cleaning liquid.

JP 2013-154490 A JP 2019-1028 A

The cleaning solution stored in the cleaning solution tank described above is composed of 60% to 90% water, and if it is left in the air, the water evaporates and the viscosity increases. For example, if the water content is reduced by 40%, the viscosity will increase by about 2.5 times.

When the viscosity of the cleaning liquid stored in the cleaning liquid tank becomes high in this way, there is a problem that the drainage path may become clogged when the cleaning liquid is discharged from the cleaning liquid tank, for example when replacing the cleaning liquid.

Patent document 2 proposes a method of periodically draining the cleaning solution at a preset timing to prevent clogging of the drainage path of the cleaning solution tank.

However, even with the method described in Patent Document 2, the viscosity of the cleaning liquid increases due to evaporation of water within a fixed period of time, reducing the ability to drain the cleaning liquid. Furthermore, with the device described in Patent Document 2, if the device body cannot be turned on for an extended period of time, for example due to a power outage, the drain path will become clogged when the cleaning liquid is drained the next time the power is turned on unless all of the cleaning liquid is drained from the cleaning liquid tank. Furthermore, draining all of the cleaning liquid from the cleaning liquid tank is time-consuming.

The present invention aims to provide a wiper cleaning device that can prevent clogging of the drainage path of the cleaning liquid tank.

The wiper cleaning device of the present invention includes a cleaning liquid tank that stores a cleaning liquid for cleaning a wiper that wipes the outlet of a discharge unit having an outlet that discharges liquid, a storage section that stores a liquid different from the cleaning liquid, which reduces the viscosity of the cleaning liquid in the cleaning liquid tank and prevents clogging of the cleaning liquid discharge path of the cleaning liquid tank, and a supply section that supplies the liquid stored in the storage section to the cleaning liquid tank.

The wiper cleaning device of the present invention is provided with a storage section that stores a liquid that is different from the cleaning liquid and that reduces the viscosity of the cleaning liquid in the cleaning liquid tank and prevents clogging of the cleaning liquid drainage path of the cleaning liquid tank, and a supply section that supplies the liquid stored in the storage section to the cleaning liquid tank. By supplying the liquid into the cleaning liquid tank, the viscosity of the cleaning liquid can be reduced and clogging of the drainage path of the cleaning liquid tank can be prevented.

FIG. 1 is a schematic diagram showing the configuration of an inkjet printing apparatus using an embodiment of a wiper cleaning device of the present invention FIG. 2 is a view of the inkjet printing apparatus shown in FIG. 1 from the direction of the arrow A. FIG. 1 is a diagram showing a schematic configuration of an example of a head unit; FIG. 2 is a perspective view showing a schematic configuration of a wiping unit; 5 is a cross-sectional view of the wiping unit shown in FIG. 4 along line B-B. A block diagram showing the configuration of a control system of an inkjet printing device. A flowchart for explaining a water supply operation of a wiping unit. FIG. 11 is a block diagram showing the configuration of a control system of an inkjet printing apparatus using another embodiment of the wiper cleaning device of the present invention.

The following describes in detail an inkjet printing device using one embodiment of the wiper cleaning device of the present invention with reference to the drawings. The inkjet printing device of this embodiment is characterized by the configuration of a wiping unit that corresponds to the wiper cleaning device of the present invention, but first, the configuration of the entire inkjet printing device will be described. Figure 1 is a schematic diagram of the inkjet printing device 1 of this embodiment. Also, Figure 2 is a view of the inkjet printing device 1 shown in Figure 1 as seen from the direction of arrow A. In the following description of the embodiment, the up, down, left, right, front, back, and rear indicated by the arrows in Figure 1 are the up, down, left, right, front, and rear directions of the inkjet printing device 1.

As shown in FIG. 1, the inkjet printing device 1 of this embodiment includes a base 2, a foot stand 3, a platen 4, a rail section 5, a head unit 10, and a wiping unit 20.

The bases 2 are columnar members extending in the front-rear direction and arranged in parallel with a gap in the left-right direction. Two wheels 2a are provided on the bottom surface of each of the two bases 2.

A stand 3 is erected on each base 2. A platen 4 is supported on the upper surfaces of the two opposing stand 3.

Front paper guide 4a and rear paper guide 4b are formed in an arc shape and extend from the front and rear of platen 4. In addition, as shown in FIG. 2, a vacuum chamber 4c in which a fan 4d is installed is provided below platen 4. Note that the vacuum chamber 4c is not shown in FIG. 1.

When the fan 4d in the vacuum chamber 4c rotates, negative pressure is created inside the vacuum chamber 4c, and suction force is generated in the suction holes (not shown) formed in the platen 4. The suction force generated in the suction holes of the platen 4 causes the printing paper P to be attracted to the platen 4.

As shown in FIG. 2, a drive roller 6 and a pressure roller 7 are provided behind the platen 4, facing each other. Note that the drive roller 6 and the pressure roller 7 are omitted from FIG. 1.

The drive roller 6 is a long roller extending in the extension direction of the platen 4, and is rotated by the transport drive motor 61 (see FIG. 6), which will be described later.

The pressure roller 7, like the drive roller 6, is an elongated roller that extends in the extension direction of the platen 4 and is supported so that it can be raised and lowered by a lifting mechanism not shown.

The printing paper P on the rear paper guide 4b is then clamped between the drive roller 6 and the pressure roller 7, and as the drive roller 6 rotates while the pressure roller 7 presses the printing paper P, the printing paper P is sent forward.

A take-up side core holder 8 is provided on the front side of the base 2 of the inkjet printing device 1, which detachably holds the core 8a around which the printing paper P is wound. The take-up side core holder 8 is connected to a take-up drive motor 81 (see FIG. 6) via a torque limiter (not shown), and is configured so that the take-up side core holder 8 rotates due to the take-up drive motor 81.

A supply-side core holder 9 is provided on the rear side of the base 2 of the inkjet printing device 1, which detachably holds a core 9a of rolled paper on which printing paper P is wound in a roll shape. The supply-side core holder 9 is connected to a supply drive motor 91 (see FIG. 6) via a torque limiter (not shown), and is configured so that the supply-side core holder 9 is rotated by the supply drive motor 91.

As shown in FIG. 2, the roll paper (print paper P) held by the supply-side core holder 9 is pulled out and passes through the rear paper guide 4b, between the drive roller 6 and pressure roller 7, over the platen 4, and the front paper guide 4a, before being wound onto the core 8a held by the winding-side core holder 8.

A rail section 5 is mounted on the top of the two legs 3 via a support member (not shown). The rail section 5 includes a rail (not shown) extending in the left-right direction and a main scanning drive motor 54 (see FIG. 6) that moves the head unit 10 back and forth in the left-right direction on the rail.

A wiping unit 20 is provided at one end of the rail portion 5. The head unit 10 is placed inside the wiping unit 20, and wiping is performed by the wiping unit 20. In this embodiment, the wiping unit 20 includes a configuration that corresponds to the wiper cleaning device of the present invention.

Figure 3 is a diagram showing the schematic configuration of the head unit 10. As shown in Figure 3, the head unit 10 of this embodiment is provided with five heads, namely, a first head 11 to a fifth head 15. The first head 11, the second head 12, the third head 13 and the fourth head 14 are inkjet heads that eject ink of different colors, for example, C (cyan), M (magenta), Y (yellow) and K (black).

The fifth head 15 has a similar configuration to the first head 11 to the fourth head 14, but ejects a pretreatment liquid instead of ink. The pretreatment liquid is a liquid that is applied for pretreatment before ink is ejected onto the printing paper P to perform the printing process. As the pretreatment liquid, for example, a liquid that improves the color development and uniform application of the ink is used, but a pretreatment liquid that is already known can be used.

As shown in FIG. 3, the first to fifth heads 11 to 15 are arranged side by side in the direction of movement of the head unit 10 (left and right direction), but the first to fourth heads 11 to 14 and the fifth head 15 are arranged in a staggered manner.

In other words, the first to fourth heads 11 to 14 are arranged at the same position in the direction perpendicular to the movement direction of the head unit 10 (front-to-back direction), but the first to fourth heads 11 to 14 and the fifth head 15 are arranged at different positions in the direction perpendicular to the movement direction of the head unit 10 (front-to-back direction).

Next, the wiping unit 20 of this embodiment will be described. FIG. 4 is a perspective view showing the schematic configuration of the wiping unit 20 of this embodiment. FIG. 5 is a cross-sectional view of the wiping unit 20 shown in FIG. 4 taken along line B-B.

The wiping unit 20 includes a cleaning liquid tank 20a, first to fifth wipers 21a to 21e, first and second belt conveyor rollers 23, 24, and first and second conveyor belts 22, 25.

The first to fourth wipers 21a to 21d correspond to the first to fourth heads 11 to 14, and wipe the ejection surfaces of the first to fourth heads 11 to 14. The ejection surface is the surface on which the ink ejection openings of the nozzles of the inkjet head are arranged.

The fifth wiper 21e is a wiper that corresponds to the fifth head 15 and wipes the ejection surface of the fifth head 15.

The first to fifth wipers 21a to 21e are arranged at intervals equal to the intervals between the first to fifth heads 11 to 15 in the movement direction of the head unit 10.

The first to fourth wipers 21a to 21d are erected at the same positions in the front-to-rear direction on the first conveyor belt 22. The fifth wiper 21e is erected on the second conveyor belt 25.

The first to fifth wipers 21a to 21e are made of flexible rubber or similar material.

The cleaning liquid tank 20a stores the cleaning liquid. The cleaning liquid tank 20a has two recesses, a first cleaning liquid tank 20c and a second cleaning liquid tank 20d, and a partition wall 20b is provided between the first cleaning liquid tank 20c and the second cleaning liquid tank 20d. In other words, the first cleaning liquid tank 20c and the second cleaning liquid tank 20d are formed as completely independent cleaning liquid tanks.

The cleaning liquid is a liquid that has the function of dissolving ink. For example, an aqueous solvent containing water and a surfactant can be used as this cleaning liquid.

Examples of surfactants that can be used include anionic surfactants such as sodium fatty acid, sodium alkylbenzenesulfonate, sodium alkylsulfonate, sodium α-olefinsulfonate, sodium alkyl sulfate, sodium alkyl ether sulfate, sodium α-sulfofatty acid ester, and sodium alkyl phosphate; cationic surfactants such as alkyltrimethylammonium and dialkyldimethylammonium; nonionic surfactants such as sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, sucrose fatty acid ester, polyoxyethylene alkyl ether, and polyoxyethylene alkylphenyl ether; and amphoteric surfactants such as sodium alkylamino fatty acid, alkyl betaine, and alkylamine oxide. Polymer surfactants, silicone surfactants, fluorine surfactants, and acetylene glycol surfactants can also be used. Among these, it is preferable to use polyoxyethylene alkyl ether, and it is more preferable that the HLB value is 11 to 17, the number of carbon atoms in the alkyl group is 8 to 15, and the number of moles of ethylene oxide added is 6 to 25.

It is preferable that the cleaning solution further contains a thickener. As the thickener, a water-soluble polymer-based thickener or a clay mineral-based thickener can be used. As the water-soluble polymer-based thickener, a natural polymer, a semi-synthetic polymer, or a synthetic polymer can be used. As the natural polymer, for example, a plant-based natural polymer such as gum arabic, carrageenan, guar gum, locust bean gum, pectin, tragacanth gum, corn starch, konjac mannan, agar, etc.; a microbial natural polymer such as pullulan, xanthan gum, dextrin, etc.; an animal-based natural polymer such as gelatin, casein, or glue can be used. As the semi-synthetic polymer, for example, a cellulose-based semi-synthetic polymer such as ethyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, or hydroxypropyl methyl cellulose can be used; a starch-based semi-synthetic polymer such as hydroxyethyl starch, sodium carboxymethyl starch, or cyclodextrin; an alginic acid-based semi-synthetic polymer such as sodium alginate or propylene glycol alginate; or sodium hyaluronate can be used. Examples of synthetic polymers that can be used include vinyl synthetic polymers such as polyvinylpyrrolidone, polyvinyl alcohol, polyvinyl methyl ether, poly N-vinylacetamide, and polyacrylamide; polyethylene oxide, polyethyleneimine, and polyurethane. Examples of clay mineral thickeners that can be used include smectite clay minerals such as montmorillonite, hectorite, and saponite. Of these, it is preferable to use hydroxypropyl methylcellulose.

In addition to the above components, the cleaning solution may optionally contain water-soluble organic solvents, pH adjusters, antioxidants, preservatives, etc. The viscosity of the cleaning solution is preferably 3 to 200 mPa·s at 23°C.

The first cleaning liquid tank 20c contains a first conveyor belt 22 with first to fourth wipers 21a to 21d standing on it, and the second cleaning liquid tank 20d contains a second conveyor belt 25 with a fifth wiper 21e standing on it.

In addition, first and second belt conveying rollers 23, 24 are provided in the first cleaning liquid tank 20c and the second cleaning liquid tank 20d. The first and second belt conveying rollers 23, 24 extend in the left-right direction across the first cleaning liquid tank 20c and the second cleaning liquid tank 20d.

The first and second belt conveyor rollers 23, 24 are arranged in parallel with a gap of at least the length of the head unit 10 in the front-to-rear direction, and the first conveyor belt 22 and the second conveyor belt 25 are stretched between the first belt conveyor roller 23 and the second belt conveyor roller 24.

As shown in FIG. 5, the first belt conveyor roller 23 and the second belt conveyor roller 24 are rotated in the direction of arrow C by the belt drive motor 39 (see FIG. 6), thereby moving the first and second conveyor belts 22, 25. This causes the first to fifth wipers 21a to 21e to move in the front-to-back direction (the direction in which the nozzles of the first to fifth heads 11-15 are arranged) and wipe the ejection surfaces of the first to fifth heads 11-15. In this embodiment, the first and second belt conveyor rollers 23, 24, the first and second conveyor belts 22, 25, and the belt drive motor 39 correspond to the wiper conveyor unit of the present invention.

In addition, while FIG. 5 shows only the third head 13 being wiped by the third wiper 21c as a representative example, the first to second and fourth to fifth wipers 21a, 21b, 21d, and 21e wipe the first to second and fourth to fifth heads 11, 12, 14, and 15 in a similar manner. In addition, L in FIG. 5 is cleaning liquid, and cleaning liquid L is stored up to the lower half of the first and second conveyor belts 22 and 25.

As shown in Figs. 4 and 5, a storage section 26 is provided behind the cleaning liquid tank 20a. The storage section 26 includes a water storage tank 26a and a lid section 26b. The water storage tank 26a is a tank that stores water, and the lid section 26b functions as a lid for the water storage tank 26a and suppresses evaporation of water from the water storage tank 26a.

One end of the water supply pipe 28 is connected to the bottom of the water storage tank 26a, and the other end of the water supply pipe 28 is connected to a water supply hole 28a formed in the side wall of the cleaning liquid tank 20a. The water supply hole 28a is formed in each of the first cleaning liquid tank 20c and the second cleaning liquid tank 20d. Between the supply unit 27 described below and the first cleaning liquid tank 20c and the second cleaning liquid tank 20d, the water supply pipe 28 is bifurcated and is connected to the water supply hole 28a formed in the first cleaning liquid tank 20c and the water supply hole 28a formed in the second cleaning liquid tank 20d, respectively.

The water supply pipe 28 is provided with the above-mentioned supply unit 27. The supply unit 27 has a pump, a valve, etc., and supplies the water stored in the water storage tank 26a to each of the first cleaning liquid tank 20c and the second cleaning liquid tank 20d via the water supply pipe 28.

The first cleaning liquid tank 20c and the second cleaning liquid tank 20d are provided with a liquid volume detection unit 30 shown in FIG. 5. The liquid volume detection unit 30 is omitted in FIG. 4. The liquid volume detection unit 30 detects the amount of cleaning liquid stored in the first cleaning liquid tank 20c. The liquid volume detection unit 30 may be configured with a sensor that detects the liquid level of the cleaning liquid, or may be configured with a sensor that directly detects the amount of cleaning liquid. In this embodiment, the first cleaning liquid tank 20c and the second cleaning liquid tank 20d have the same amount of reduced cleaning liquid (amount of water evaporated), so the liquid volume detection unit 30 is provided only in the first cleaning liquid tank 20c, but it may be provided in both the first cleaning liquid tank 20c and the second cleaning liquid tank 20d.

When the liquid volume detection unit 30 detects that the amount of cleaning liquid (liquid surface height) stored in the first cleaning liquid tank 20c is below a preset threshold, the detection signal is output to the print control device 16, which will be described later.

The print control device 16 outputs a control signal to the supply unit 27 based on the input detection signal, and the supply unit 27 drives pumps, valves, etc. in response to the control signal output from the print control device 16 to supply water from the water storage tank 26a to the first cleaning liquid tank 20c and the second cleaning liquid tank 20d.

In this way, by supplying water into the first cleaning liquid tank 20c and the second cleaning liquid tank 20d, the viscosity of the cleaning liquid can be reduced, and clogging of the discharge pipe 29 of the first cleaning liquid tank 20c and the second cleaning liquid tank 20d, which will be described later, can be prevented. In this embodiment, the viscosity of the cleaning liquid is reduced by storing water in the storage section 26 and supplying it to the first and second cleaning liquid tanks 20c and 20d. However, the liquid stored in the storage section 26 is not limited to water, and may be any liquid other than the cleaning liquid that reduces the viscosity of the cleaning liquid in the cleaning liquid tank and prevents clogging of the discharge path of the cleaning liquid in the cleaning liquid tank. For example, as long as the liquid has the above-mentioned function, it is acceptable for the water to contain some impurities such as ink components.

However, by using water as in this embodiment, a higher cleaning effect can be obtained, and compared to using a liquid other than water, costs can be reduced and handling is easy.

After the supply of water has started, if the amount of cleaning liquid (liquid level) stored in the first cleaning liquid tank 20c exceeds a preset threshold, the liquid volume detection unit 30 outputs a detection signal to the print control device 16. In this way, by controlling the start and stop of water supply based on the detection result by the liquid volume detection unit 30, water can be supplied according to the amount of water evaporation from the cleaning liquid.

The print control device 16 then controls the supply unit 27 in response to the input detection signal to stop the water supply.

After stopping the water supply, the print control device 16 rotates the first belt conveyor roller 23 and the second belt conveyor roller 24 in the direction of arrow C to move the first to fifth wipers 21a to 21e and agitate the liquid in the first cleaning liquid tank 20c and the second cleaning liquid tank 20d; this agitation operation will be described in detail later.

In addition, drain holes 29a are provided in the side walls of the first cleaning liquid tank 20c and the second cleaning liquid tank 20d, and drain pipes 29 are connected to the drain holes 29a. When replacing the cleaning liquid L in the cleaning liquid tank 20a, the cleaning liquid is drained from the drain holes 29a to the drain pipe 29. The drain pipe 29 is also provided with a pump and a valve (not shown), which are controlled by the print control device 16 to control the drainage of the cleaning liquid.

Figure 6 is a block diagram showing the configuration of the control system of the inkjet printing device 1 of this embodiment. The inkjet printing device 1 operates each of the controlled parts shown in Figure 6 in response to a control signal from the print control device 16.

The print control device 16 and the inkjet printing device 1 are connected by a communication line such as a LAN (Local Area Network) or an Internet line, and are configured to be able to communicate with each other. The communication line may be wired or wireless.

The print control device 16 is composed of a computer equipped with a CPU (Central Processing Unit), semiconductor memory, a hard disk, etc. Based on an input print job, the print control device 16 executes a print control program stored in advance in a storage medium such as a semiconductor memory or a hard disk, and controls each part shown in FIG. 6 by operating an electric circuit.

Next, the printing operation of the inkjet printing device 1 of this embodiment will be described. Note that here, a case will be described in which pretreatment liquid is ejected from the fifth head 15 to apply it to the printing paper P, and then ink is ejected from the first to fourth heads 11 to 14 to print on the printing paper P to which the pretreatment liquid has been applied.

First, as shown in FIG. 2, a roll of paper is placed on the supply-side core holder 9, and the roll of paper (print paper P) is pulled out and passed through the rear paper guide 4b, between the drive roller 6 and pressure roller 7, over the platen 4, and the front paper guide 4a, before being wound around the core 8a held by the take-up-side core holder 8.

The print control device 16 then rotates the supply side core holding unit 9, the take-up side core holding unit 8, and the drive roller 6 to feed the print paper P, and stops feeding the print paper P when it reaches the initial printing position.

The print control device 16 then operates the main scanning drive motor 54 to move the head unit 10 in a first direction (either left or right) on the rail section 5. As the head unit 10 moves, the print control device 16 then operates the fifth head 15 of the head unit 10 to apply pretreatment liquid to the first scan line. Note that when scanning the first scan line, ink is not ejected from the first to fourth heads 11 to 14.

Next, the print control device 16 advances the print paper P by one scan line so that the first scan line to which the pretreatment liquid is applied is positioned directly below the first to fourth heads 11 to 14.

Then, the print control device 16 moves the head unit 10 on the rail section 5 in a second direction opposite to the first direction, and, as the head unit 10 moves, ejects ink from the first to fourth heads 11 to 14 to print the first scan line. The print control device 16 also prints the first scan line and operates the fifth head 15 to apply pretreatment liquid to the second scan line that follows the first scan line.

The print control device 16 then advances the print paper P by one scan line, positions the second scan line directly below the first to fourth heads 11 to 14, and positions the third scan line, which is the next to the second scan line, directly below the fifth head 15.

The print control device 16 then moves the head unit 10 in the first direction on the rail section 5, and operates the first to fourth heads 11 to 14 and the fifth head 15 in conjunction with the movement, thereby applying pretreatment liquid to the third scan line and printing the second scan line.

Then, the print control device 16, in the same manner as described above, alternates between feeding out one scan line of print paper P and moving the head unit 10 on the rail section 5 in the first direction or the second direction, sequentially applying pretreatment liquid to the (n+1)th scan line and printing on the nth scan line.

Next, the wiping operation of the inkjet printing device 1 of this embodiment will be described.

The wiping operation is performed during a standby period when no printing process is being performed. At this time, the print control device 16 moves the head unit 10 on the rail section 5 and positions it above the wiping unit 20 as shown in FIG. 5.

Then, the print control device 16 moves the first to fifth wipers 21a to 21e, which are immersed in the cleaning liquid in the first and second cleaning liquid tanks 20c and 20d, using the first and second conveyor belts 22 and 25, and positions the tips of the first to fifth wipers 21a to 21e at the front ends of the corresponding first to fifth heads 11 to 15.

The print control device 16 then moves the first to fifth wipers 11 to 15 in this state so that the tips of the first to fifth wipers 21a to 21e are pressed against the ejection surfaces of the first to fifth heads 11 to 15 and are elastically deformed. At this time, the print control device 16 may move the head unit 10 downward or move the wiping unit 20 upward in order to press the tips of the first to fifth wipers 21a to 21e against the ejection surfaces of the first to fifth heads 11 to 15.

Then, while the tips of the first to fifth wipers 21a to 21e are pressed against the ejection surfaces of the first to fifth heads 11 to 15, the print control device 16 further moves the first to fifth wipers 21a to 21e, thereby wiping the ejection surfaces of the first to fifth heads 11 to 15.

Then, the print control device 16 ends wiping by moving the tips of the first to fifth wipers 21a to 21e to the rear ends of the first to fifth heads 11 to 15, and then moves the first to fifth wipers 21a to 21e further, so that they are again immersed in the cleaning liquid in the first cleaning liquid tank 20c and the second cleaning liquid tank 20d.

The wiping operation described above may be performed automatically just before the printing process starts, or in response to a user instruction. It may also be performed at preset intervals or for a preset length of the printing range (amount of printing paper P fed out).

Next, the water supply operation in the wiping unit 20 of the inkjet printing device 1 of this embodiment will be described. The explanation will be given with reference to the flowchart shown in FIG. 7.

First, as described above, the amount of cleaning liquid stored in the first cleaning liquid tank 20c is monitored by the liquid volume detection unit 30 (S10).

Then, when the cleaning liquid stored in the first cleaning liquid tank 20c falls below a preset threshold value (S12, YES), a detection signal is output from the liquid volume detection unit 30 to the print control device 16.

When the print control device 16 receives a detection signal from the liquid volume detection unit 30, it controls the supply unit 27 to supply water from the storage unit 26 to the first cleaning liquid tank 20c and the second cleaning liquid tank 20d when the wiping unit 20 is in a standby state (S14). Note that the wiping unit 20 is in a standby state when the first to fifth wipers 21a to 21e are immersed in the cleaning liquid in the first cleaning liquid tank 20c and the second cleaning liquid tank 20d, not when the wiping operation described above is in progress.

After the water supply has started, if the liquid volume detection unit 30 detects that the amount of cleaning liquid stored in the first cleaning liquid tank 20c has exceeded a preset threshold value (S16, YES), a detection signal is output to the print control device 16, which then controls the supply unit 27 to stop the water supply (S18).

Then, the print control device 16 rotates the first belt conveyor roller 23 and the second belt conveyor roller 24 in the direction of the arrow C, and moves the first to fifth wipers 21a to 21e in the standby state to perform the stirring operation (S20). In this embodiment, the print control device 16 moves the first to fifth wipers 21a to 21e until they return to their original standby positions. That is, the print control device 16 in this embodiment moves the first to fifth wipers 21a to 21e by a distance equal to the length of the first and second conveyor belts 22, 25. This stirs the liquid in the first and second cleaning liquid tanks 20c, 20d, and the cleaning liquid can be mixed with the newly supplied water. In addition, since stirring is performed by moving the first to fifth wipers 21a to 21e, there is no need to provide a new stirring mechanism, which can reduce costs.

The movement speed of the first to fifth wipers 21a to 21e when performing the stirring operation is preferably faster than the movement speed when performing the wiping operation described above. This can improve the stirring performance of the liquid in the first and second cleaning liquid tanks 20c and 20d.

In addition, in this embodiment, the first to fifth wipers 21a to 21e are rotated once during the stirring operation, but this is not limited to this and they may be rotated two or more times.

After the above-mentioned stirring operation, the process returns to S10, and the amount of cleaning liquid is monitored by the liquid volume detection unit 30.

In the above embodiment, water is supplied from one storage section 26 to two cleaning liquid tanks, the first cleaning liquid tank 20c and the second cleaning liquid tank 20d. However, a storage section 26 and a supply section 27 may be provided for each of the first cleaning liquid tank 20c and the second cleaning liquid tank 20d. The supply of water to the first cleaning liquid tank 20c and the second cleaning liquid tank 20d may be controlled independently based on the detection signal of the liquid volume detection section 30 provided in each of the first cleaning liquid tank 20c and the second cleaning liquid tank 20d.

In addition, in the above embodiment, the supply of water is controlled based on the amount of cleaning liquid detected by the liquid amount detection unit 30, but this is not limited to the above. For example, as shown in FIG. 8, a time measurement unit 31 may be provided in the print control device 16, and water may be supplied to the first cleaning liquid tank 20c and the second cleaning liquid tank 20d based on the elapsed time measured by the time measurement unit 31.

Specifically, for example, the time elapsed from the point when all the cleaning liquid is drained from the first cleaning liquid tank 20c and the second cleaning liquid tank 20d and new cleaning liquid is supplied may be measured by the time measurement unit 31, and when the measured elapsed time reaches a preset threshold value, the print control device 16 may control the supply unit 27 to supply a preset amount of water (an amount equivalent to the amount of evaporation of water) to the first cleaning liquid tank 20c and the second cleaning liquid tank 20d. In this way, by controlling the supply and stop of water based on the measurement result of the elapsed time by the time measurement unit 31, the supply of water according to the amount of evaporation of the cleaning liquid can be performed by a simple configuration such as a timer.

In the above embodiment, the first to fifth wipers 21a to 21e are used to agitate the liquid in the first and second cleaning liquid tanks 20c, 20d. However, in addition to the first to fifth wipers 21a to 21e, an agitation mechanism may be provided for the first and second conveyor belts 22, 25, the first belt conveyor roller 23, or the second belt conveyor roller 24, and the agitation operation may be performed by rotating the first and second belt conveyor rollers 23, 24 using the agitation mechanism. This can improve the agitation performance.

The present invention further discloses the following supplementary notes.
(Additional Note)

The wiper cleaning device of the present invention can be provided with a liquid volume detection unit that detects the amount of cleaning liquid stored in the cleaning liquid tank, and the supply unit can supply liquid to the cleaning liquid tank based on the amount of cleaning liquid detected by the liquid volume detection unit.

The wiper cleaning device of the present invention can be provided with a time measurement unit that measures the elapsed time, and the supply unit can supply liquid to the cleaning liquid tank based on the elapsed time measured by the time measurement unit.

The wiper cleaning device of the present invention can be provided with a wiper transport section that moves the wiper to wipe the outlet of the discharge section and immerses the wiper in the cleaning liquid tank after wiping and moves it. When liquid is supplied from the storage section to the cleaning liquid tank, the wiper transport section immerses the wiper in the cleaning liquid tank and moves it, and the wiper can agitate the inside of the cleaning liquid tank.

In the wiper cleaning device of the present invention, the wiper transport section can move the wiper faster when stirring the inside of the cleaning liquid tank than when wiping the outlet of the discharge section.
In the wiper cleaning device of the present invention, the liquid stored in the storage portion is preferably water.

1 Inkjet printing device 2 Base 2a Wheel 3 Foot 4 Platen 4a Front paper guide 4b Rear paper guide 4c Vacuum chamber 4d Fan 5 Rail section 6 Drive roller 7 Pressure roller 8 Take-up side core body holding section 8a Core body 9 Supply side core body holding section 9a Core body 10 Head units 11 to 15 First to fifth heads 16 Print control device 20 Wiping unit 20a Cleaning liquid tank 20b Partition wall 20c First cleaning liquid tank 20d Second cleaning liquid tank 21a to 21e First to fifth wipers 22 First conveyor belt 23 First belt conveyor roller 24 Second belt conveyor roller 26 Storage section 26a Water storage tank 26b Lid section 27 Supply section 28 Water supply pipe 28a Water supply hole 29 Discharge pipe 29 Discharge hole 29a Discharge hole 30 Liquid amount detection section 31 Time measurement section 39 Belt drive motor 54 Main scanning drive motor 61 Transport drive motor 81 Winding drive motor 91 Supply drive motor L Cleaning liquid P Printing paper

Claims (6)

a cleaning liquid tank for storing a cleaning liquid for cleaning a wiper that wipes the discharge port of a discharge unit having a discharge port for discharging a liquid;
a storage section for storing a liquid different from the cleaning liquid, the liquid reducing the viscosity of the cleaning liquid in the cleaning liquid tank and preventing clogging of a drainage path of the cleaning liquid in the cleaning liquid tank;
and a supply section that supplies the liquid stored in the storage section to the cleaning liquid tank when the viscosity of the cleaning liquid in the cleaning liquid tank becomes high . a cleaning liquid tank for storing a cleaning liquid for cleaning a wiper that wipes the discharge port of a discharge unit having a discharge port for discharging a liquid;
a storage section for storing a liquid different from the cleaning liquid, the liquid reducing the viscosity of the cleaning liquid in the cleaning liquid tank and preventing clogging of a drainage path of the cleaning liquid in the cleaning liquid tank;
a supply unit that supplies the liquid stored in the storage unit to the cleaning liquid tank;
a liquid amount detection unit that detects an amount of the cleaning liquid stored in the cleaning liquid tank,
A wiper cleaning device, wherein the supply unit supplies the liquid to the cleaning liquid tank based on the amount of cleaning liquid detected by the liquid amount detection unit. a cleaning liquid tank for storing a cleaning liquid for cleaning a wiper that wipes the discharge port of a discharge unit having a discharge port for discharging a liquid;
a storage section for storing a liquid different from the cleaning liquid, the liquid reducing the viscosity of the cleaning liquid in the cleaning liquid tank and preventing clogging of a drainage path of the cleaning liquid in the cleaning liquid tank;
a supply unit that supplies the liquid stored in the storage unit to the cleaning liquid tank;
a time measurement unit that measures an elapsed time,
A wiper cleaning device, wherein the supply unit supplies the liquid to the cleaning liquid tank based on the elapsed time measured by the time measurement unit. a wiper transport unit that moves the wiper so as to wipe the discharge port of the discharge unit and that transports the wiper after wiping while immersing it in the cleaning liquid tank,
A wiper cleaning device as described in any one of claims 1 to 3, wherein when liquid in the storage section is supplied from the storage section to the cleaning liquid tank, the wiper transport section immerses the wiper in the cleaning liquid tank and moves it, thereby agitating the cleaning liquid tank with the wiper. The wiper cleaning device according to claim 4, wherein the wiper conveying unit moves the wiper faster when stirring the cleaning liquid tank than when wiping the outlet of the discharge unit. A wiper cleaning device according to any one of claims 1 to 5, wherein the liquid stored in the storage section is water.