Cleaning device and recording device

Abstract

To provide a cleaning device which can accurately detect a density of an ink mixed into a cleaning liquid to discharge the cleaning liquid properly, and to provide a recording device.SOLUTION: A cleaning device includes: a storage part which stores a cleaning liquid for cleaning a conveyor belt for conveying a medium; an optical sensor which detects an ink density of a dye ink mixed into the cleaning liquid stored in the storage part; and a control unit which performs control to discharge the cleaning liquid from the storage part. The optical sensor has: a light emitting part which emits light; and a light reception part which receives the light emitted from the light emitting part. The control unit performs control so as to discharge the cleaning liquid from the storage part based on a detection result of the optical sensor. The light emitted by the light emitting part includes light having a wave length of 400 nm or shorter.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a cleaning apparatus and a recording apparatus. [Background technology]

[0002] Patent Document 1 describes a cleaning device that uses cleaning liquid to clean a transport belt that transports a medium. In the cleaning device, ink becomes mixed into the cleaning liquid as the transport belt is cleaned. The cleaning device detects the concentration of ink mixed into the cleaning liquid based on the amount of light transmitted through the cleaning liquid. If the ink concentration is high, the cleaning device discharges the cleaning liquid. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-213394 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in such a cleaning device, it is not easy to accurately detect the ink concentration based on the amount of light transmitted through the cleaning liquid for ink that has been dissolved in the cleaning liquid and does not contain particles. Thus, it is desired to accurately detect the ink concentration that has mixed into the cleaning liquid and to appropriately discharge the cleaning liquid. [Means for solving the problem]

[0005] A cleaning device that solves the above problem includes a storage section that stores cleaning liquid used to clean a conveyor belt that transports a medium, an optical sensor that detects the ink concentration of dye ink mixed into the cleaning liquid stored in the storage section, and a control section that controls the cleaning liquid to be discharged from the storage section, wherein the optical sensor has an emitter that emits light and a light receiver that receives the light emitted from the emitter, and the control section controls the cleaning liquid to be discharged from the storage section based on the detection result by the optical sensor, and the light emitted by the light emitter includes light with a wavelength of 400 nm or less.

[0006] A recording apparatus that solves the above problem includes the above cleaning device, a transport unit having the transport belt, and a recording unit that performs recording by ejecting dye ink onto a medium transported by the transport unit. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram showing a recording apparatus equipped with a cleaning device according to a first embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing a detection unit in the first embodiment. [Diagram 3] FIG. 3 is a graph showing the wavelength of light and the transmittance of dye ink in the first embodiment. [Figure 4] FIG. 4 is a graph showing the wavelength of light and the transmittance of dye ink in the first embodiment. [Diagram 5] FIG. 5 is a graph showing the relationship between ink density and output level in the first embodiment. [Figure 6] FIG. 6 is a graph showing the relationship between ink density and output level in the first embodiment. [Figure 7] FIG. 7 is a graph showing the relationship between the transmittance of the dye ink and the coefficient of determination, and the relationship between the transmittance of the dye ink and the gradient of the ink density of the dye ink in the first embodiment. [Figure 8] FIG. 8 is a graph showing the relationship between ink density and output level in the first embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] [First embodiment] An embodiment of a recording apparatus equipped with a cleaning device will be described below. <Configuration of Recording Device 11> As shown in FIG. 1, the recording device 11 is an inkjet printer that records an image by ejecting a liquid onto a medium. The medium may be, for example, fabric, paper, etc. The image may be text, a photograph, etc. The liquid may be, for example, a dye ink. The liquid may include a reactive dye ink. The liquid may include, for example, an acid dye ink. That is, the liquid may include a reactive dye ink or an acid dye ink.

[0009] Dye inks are inks that contain dye in a solvent. Dye inks include inks that dissolve in the cleaning fluid to eliminate the presence of particles in the cleaning fluid. Dye inks may include, for example, black, cyan, yellow, magenta, red, orange, green, light black, and other inks.

[0010] <Configuration of recording unit 12> The recording device 11 includes a recording unit 12. The recording unit 12 is configured to eject liquid onto a medium 99. The recording unit 12 is configured to eject liquid onto a medium 99 transported by a transport unit 21, which will be described in detail later. In this way, the recording unit 12 records an image on the medium 99. The recording unit 12 is a head. The recording unit 12 has a nozzle surface 14 in which one or more nozzles 13 are opened. The recording unit 12 ejects liquid from the nozzles 13. The recording unit 12 may be a serial head that scans the medium 99. The recording unit 12 may be a line head that can eject liquid simultaneously across the width of the medium 99.

[0011] <Configuration of the conveying unit 21> The recording device 11 includes a transport unit 21. The transport unit 21 is configured to transport a medium 99. In the process in which the transport unit 21 transports the medium 99, liquid is ejected from the recording unit 12 onto the medium 99.

[0012] The transport unit 21 is configured to transport the medium 99 in the transport direction A1. The transport unit 21 has a plurality of transport rollers. In one example, the transport unit 21 has a first transport roller 22 and a second transport roller 23. The first transport roller 22 is located upstream of the recording unit 12 in the transport direction A1. The second transport roller 23 is located downstream of the recording unit 12 in the transport direction A1.

[0013] The transport unit 21 has a driving source 24. The driving source 24 is, for example, a motor. The driving source 24 is connected to at least one of the multiple transport rollers. In one example, the driving source 24 is connected to the first transport roller 22. The first transport roller 22 is rotated by the driving source 24.

[0014] The transport unit 21 has a transport belt 25. The transport belt 25 is wound around a plurality of transport rollers. In one example, the transport belt 25 is wound around a first transport roller 22 and a second transport roller 23. The drive source 24 rotates the first transport roller 22, so that the transport belt 25 rotates along the first transport roller 22 and the second transport roller 23. In FIG. 1, the transport belt 25 rotates counterclockwise. As a result, the transport belt 25 transports the medium 99. The transport belt 25 supports the medium 99 on which an image is recorded by the recording unit 12.

[0015] The conveyor belt 25 includes a portion that moves in the conveying direction A1 and a portion that moves in an opposite direction A2 opposite to the conveying direction A1. The conveyor belt 25 conveys the medium 99 by the portion that moves in the conveying direction A1. The portion that moves in the opposite direction A2 is cleaned by a cleaning device 31, which will be described later.

[0016] The transport belt 25 has an inner circumferential surface 26 and an outer circumferential surface 27. The inner circumferential surface 26 is a surface that contacts a plurality of transport rollers. In one example, the inner circumferential surface 26 contacts the first transport roller 22 and the second transport roller 23. The outer circumferential surface 27 is a surface that contacts the medium 99. The outer circumferential surface 27 is a surface that supports the medium 99. The outer circumferential surface 27 faces the nozzle surface 14.

[0017] The conveyor belt 25 is configured to be capable of adhering the medium 99. More specifically, the medium 99 is adhered to the outer peripheral surface 27. This allows the medium 99 to be conveyed in a stable position. In one example, the conveyor belt 25 is an adhesive belt to which an adhesive is applied. The adhesive is applied to the outer peripheral surface 27. In this case, the medium 99 is adhered to the outer peripheral surface 27 by the adhesive. The medium 99 may be adhered to the outer peripheral surface 27 by, for example, suction force, electrostatic force, intermolecular force, etc., without being limited to the adhesive. After an image is recorded on the medium 99 by the recording unit 12, the medium 99 is peeled off from the outer peripheral surface 27 by, for example, being pulled by another device. The conveyor unit 21 may have a peeling unit that peels off the medium 99 from the outer peripheral surface 27. In this case, the peeling unit is, for example, a roller around which the medium 99 is wound.

[0018] The transport unit 21 may have a pressing unit 28. The pressing unit 28 is configured to press the medium 99 against the transport belt 25. In one example, the pressing unit 28 is a roller. The pressing unit 28 presses the medium 99 against the transport belt 25, so that the medium 99 is adhered to the outer circumferential surface 27.

[0019] In the conveyor belt 25, as the recording unit 12 records an image on the medium 99, the dye ink discharged as a liquid may adhere to the outer peripheral surface 27. If the conveyor belt 25 continues to convey the medium 99 with the dye ink adhering to the outer peripheral surface 27, the medium 99 may become soiled.

[0020] <Configuration of the recording control unit 15> The recording device 11 includes a recording control unit 15. The recording control unit 15 may control the recording unit 12. The recording control unit 15 may control the transport unit 21. The recording control unit 15 may be configured with one or more processors. The processor executes various processes according to a computer program. The recording control unit 15 may be configured with one or more dedicated hardware circuits. The recording control unit 15 may include an application specific integrated circuit that executes at least a part of the various processes. The recording control unit 15 may be configured with a circuit including a combination of a processor and a hardware circuit. The processor includes a CPU and a memory such as a RAM and a ROM. The memory stores program code or instructions configured to cause the CPU to execute a process. The memory, i.e., a computer-readable medium, includes any readable medium that can be accessed by a general-purpose or dedicated computer.

[0021] <Configuration of cleaning device 31> The recording device 11 includes a cleaning device 31. The cleaning device 31 is configured to clean the conveyor belt 25 with a cleaning liquid. More specifically, the cleaning device 31 cleans the outer peripheral surface 27 with the cleaning liquid. The cleaning device 31 removes dye ink adhering to the outer peripheral surface 27 with the cleaning liquid. The cleaning liquid makes it easier for the dye ink to fall off from the conveyor belt 25. In this way, the cleaning liquid is a liquid for cleaning the conveyor belt 25. In one example, the cleaning liquid is water.

[0022] <Configuration of cleaning unit 32> The cleaning device 31 has a cleaning unit 32. The cleaning unit 32 cleans the conveyor belt 25 with a cleaning liquid. The cleaning unit 32 cleans the conveyor belt 25 by contacting the conveyor belt 25. More specifically, the cleaning unit 32 contacts the outer circumferential surface 27. The cleaning unit 32 contacts a portion of the conveyor belt 25 that is located in the opposite direction A2. That is, the cleaning unit 32 contacts the conveyor belt 25 after the medium 99 has been peeled off.

[0023] The cleaning unit 32 has one or more cleaning rollers 33. In one example, the cleaning unit 32 has three cleaning rollers 33. The cleaning rollers 33 come into contact with the conveyor belt 25 while rotating. The cleaning rollers 33 may rotate in a driven manner relative to the conveyor belt 25. That is, the cleaning rollers 33 may rotate in a driven manner clockwise in FIG. 1. The cleaning rollers 33 may rotate in a driven manner against the rotation of the conveyor belt 25. That is, the cleaning rollers 33 may rotate in a counterclockwise manner in FIG. 1. In this case, the contact resistance between the cleaning rollers 33 and the conveyor belt 25 increases. This makes it easier to remove the dye ink from the conveyor belt 25.

[0024] The cleaning roller 33 comes into contact with the transport belt 25 while wet with the cleaning liquid. This causes the transport belt 25 to become wet with the cleaning liquid. This makes it easier to remove the dye ink from the transport belt 25. The cleaning roller 33 is, for example, a brush roller. The cleaning roller 33 may also be a sponge roller.

[0025] The cleaning unit 32 has one or more cleaning blades 34. In one example, the cleaning unit 32 has three cleaning blades 34. The cleaning blade 34 contacts the conveyor belt 25 wet with the cleaning liquid. The cleaning blade 34 contacts the outer circumferential surface 27 wet with the cleaning liquid. The cleaning blade 34 scrapes off the dye ink together with the cleaning liquid adhering to the conveyor belt 25. The cleaning blade 34 contacts the conveyor belt 25 after the cleaning roller 33 contacts it. Therefore, the cleaning blade 34 is located in the opposite direction A2 from the cleaning roller 33.

[0026] <Configuration of storage section 35> The cleaning device 31 includes a storage section 35. The storage section 35 is configured to store a cleaning liquid. The storage section 35 holds the cleaning section 32. The storage section 35 is configured to store a cleaning liquid to be supplied to the cleaning section 32. The cleaning section 32 cleans the conveyor belt 25 by using the cleaning liquid stored in the storage section 35. The cleaning liquid stored in the storage section 35 gradually becomes dirty as the cleaning section 32 cleans the conveyor belt 25. That is, the cleaning liquid stored in the storage section 35 may be mixed with dye ink attached to the conveyor belt 25. As a result, the storage section 35 may store cleaning liquid mixed with dye ink. For this reason, the cleaning device 31 needs to appropriately replace the cleaning liquid stored in the storage section 35.

[0027] The storage unit 35 has a cleaning tank 36. The cleaning tank 36 is a tank that stores cleaning liquid. The cleaning tank 36 is located so as to face the outer circumferential surface 27. The cleaning tank 36 holds the cleaning unit 32. As the cleaning roller 33 cleans the conveyor belt 25, the dye ink flows into the cleaning tank 36. In other words, the cleaning tank 36 stores the cleaning liquid used by the cleaning unit 32.

[0028] The cleaning tank 36 has an immersion tank 37. The immersion tank 37 is a tank that stores a predetermined amount of cleaning liquid. The immersion tank 37 holds the cleaning roller 33. The immersion tank 37 holds the cleaning roller 33 so that the cleaning roller 33 is immersed in the stored cleaning liquid. In other words, the cleaning tank 36 is a tank that immerses the cleaning unit 32 in the stored cleaning liquid. As the cleaning roller 33 cleans the conveyor belt 25, the dye ink flows into the immersion tank 37. In other words, the immersion tank 37 stores the cleaning liquid used by the cleaning unit 32.

[0029] The cleaning tank 36 has a support tank 38. The support tank 38 supports the immersion tank 37. More specifically, the support tank 38 accommodates the immersion tank 37. The support tank 38 receives the cleaning liquid that overflows from the immersion tank 37.

[0030] The support tank 38 supports the cleaning blade 34. The support tank 38 receives the cleaning liquid that flows down the cleaning blade 34. As the cleaning blade 34 cleans the transport belt 25, the dye ink flows into the support tank 38.

[0031] The storage unit 35 has a storage tank 39. The storage tank 39 is a tank connected to the cleaning tank 36. The storage tank 39 is a tank for collecting the cleaning liquid from the cleaning tank 36. The storage tank 39 may be a tank for circulating the cleaning liquid stored in the cleaning tank 36. The storage tank 39 stores the cleaning liquid after use by the cleaning unit 32. The storage tank 39 may store the cleaning liquid after use by the cleaning unit 32.

[0032] The storage section 35 has a connection flow path. The storage section 35 may have a plurality of connection flow paths. In one example, the storage section 35 has a first connection flow path 40 and a second connection flow path 41. The first connection flow path 40 and the second connection flow path 41 are connection flow paths connected to the cleaning tank 36 and the storage tank 39. In detail, the first connection flow path 40 is connected to the support tank 38 and the storage tank 39. The second connection flow path 41 is connected to the immersion tank 37 and the storage tank 39.

[0033] The cleaning liquid flows from the cleaning tank 36 to the storage tank 39 through the first connection flow path 40. More specifically, the cleaning liquid flows from the support tank 38 to the storage tank 39 through the first connection flow path 40. The cleaning liquid flows from the storage tank 39 to the cleaning tank 36 through the second connection flow path 41. More specifically, the cleaning liquid flows from the storage tank 39 to the immersion tank 37 through the second connection flow path 41. In this way, in the storage section 35, the cleaning liquid circulates between the cleaning tank 36 and the storage tank 39. This makes it easier for the concentration of dye ink contained in the cleaning liquid to be uniform.

[0034] The cleaning device 31 may include one or more filters. The cleaning device 31 includes a cleaning filter 42 and a storage filter 43. The filters collect dust, fluff, and the like in the cleaning liquid. The cleaning filter 42 is attached to the first connection flow path 40. More specifically, the cleaning filter 42 is located at an end of the first connection flow path 40 that is connected to the cleaning tank 36. The cleaning filter 42 collects foreign matter from the cleaning liquid flowing from the cleaning tank 36 to the storage tank 39. The storage filter 43 is attached to the first connection flow path 40. More specifically, the storage filter 43 is located at an end of the first connection flow path 40 that is connected to the storage tank 39. The storage filter 43 collects foreign matter from the cleaning liquid flowing from the cleaning tank 36 to the storage tank 39.

[0035] The cleaning device 31 includes a first on-off valve 44. The first on-off valve 44 is, for example, a solenoid valve. The first on-off valve 44 is located in the first connection flow path 40. When the first on-off valve 44 is opened, the cleaning liquid can flow from the cleaning tank 36 to the storage tank 39.

[0036] The cleaning device 31 includes a pump 45. The pump 45 circulates the cleaning liquid in the storage section 35. The pump 45 circulates the cleaning liquid between the cleaning tank 36 and the storage tank 39 through the first connection flow path 40 and the second connection flow path 41. In this manner, the storage tank 39, the second connection flow path 41, and the pump 45 function as an example of a circulation section. In one example, the pump 45 is located in the second connection flow path 41. The pump 45 may be located in the first connection flow path 40.

[0037] The cleaning device 31 includes a flowmeter 46. The flowmeter 46 measures the flow rate of the cleaning liquid flowing in the storage section 35. The flowmeter 46 measures the flow rate of the cleaning liquid circulating between the cleaning tank 36 and the storage tank 39. The cleaning device 31 controls the pump 45 based on the measurement result of the flowmeter 46. In one example, the flowmeter 46 is located in the second connection flow path 41. More specifically, the flowmeter 46 is located in the second connection flow path 41 between the pump 45 and the storage tank 39. The flowmeter 46 may be located in the first connection flow path 40.

[0038] The cleaning device 31 includes a constant flow valve 47. The constant flow valve 47 is configured to maintain a constant flow rate of the cleaning liquid flowing in the storage section 35. The constant flow valve 47 is a so-called throttle valve. The constant flow valve 47 maintains a constant flow rate of the cleaning liquid circulating between the cleaning tank 36 and the storage tank 39. In one example, the constant flow valve 47 is located in the second connection flow path 41. More specifically, the constant flow valve 47 is located in the second connection flow path 41 between the pump 45 and the cleaning tank 36. The constant flow valve 47 may be located in the first connection flow path 40.

[0039] The cleaning device 31 includes a supply flow path 48. The supply flow path 48 is a flow path through which the cleaning liquid is supplied. New cleaning liquid is supplied to the cleaning device 31 through the supply flow path 48. The supply flow path 48 is connected to the storage unit 35. In one example, the supply flow path 48 is connected to the storage tank 39. The supply flow path 48 is connected to, for example, a water supply. When the amount of cleaning liquid in the storage unit 35 decreases due to evaporation of the cleaning liquid, discharge of the cleaning liquid, or the like, the cleaning liquid is supplied from the supply flow path 48 to the storage unit 35.

[0040] The cleaning device 31 includes a second on-off valve 49. The second on-off valve 49 is, for example, a solenoid valve. The second on-off valve 49 is located in the supply flow path 48. When the second on-off valve 49 is opened, the cleaning liquid is supplied to the storage section 35.

[0041] The cleaning device 31 includes a discharge flow path 50. The discharge flow path 50 is a flow path through which the cleaning liquid is discharged. The cleaning liquid is discharged from the cleaning device 31 through the discharge flow path 50. In one example, the discharge flow path 50 is connected to the storage tank 39. The discharge flow path 50 is connected to, for example, a processing device that processes waste liquid, a waste liquid tank that stores waste liquid, or the like. When the cleaning liquid becomes contaminated by dye ink, the cleaning liquid is discharged from the storage unit 35 through the discharge flow path 50.

[0042] The cleaning device 31 includes a third on-off valve 51. The third on-off valve 51 is, for example, a solenoid valve. The third on-off valve 51 is located in the discharge flow path 50. When the third on-off valve 51 is opened, the cleaning liquid is discharged from the reservoir 35.

[0043] The cleaning device 31 may include a liquid volume sensor 52. The liquid volume sensor 52 is a sensor that measures the amount of cleaning liquid stored in the storage section 35. In one example, the liquid volume sensor 52 measures the amount of cleaning liquid stored in the storage tank 39. The cleaning device 31 can maintain the amount of cleaning liquid stored in the storage section 35 at a constant amount by using the liquid volume sensor 52. For example, when the amount of cleaning liquid stored in the storage tank 39 is large, the cleaning device 31 discharges the cleaning liquid through the discharge flow path 50. When the amount of cleaning liquid stored in the storage tank 39 is small, the cleaning device 31 supplies the cleaning liquid through the supply flow path 48.

[0044] The cleaning device 31 includes a detection unit 53. The detection unit 53 is configured to detect the ink concentration of dye ink mixed in the cleaning liquid stored in the storage unit 35. The detection unit 53 is provided in the first connection flow path 40. The detection unit 53 may be provided in the second connection flow path 41. In other words, the detection unit 53 is provided in the connection flow path. Hereinafter, the ink concentration of dye ink mixed in the cleaning liquid stored in the storage unit 35 will be simply referred to as the ink concentration of dye ink.

[0045] The cleaning device 31 includes a cleaning control unit 54. The cleaning control unit 54 controls the cleaning device 31. The cleaning control unit 54 receives output results from the flow meter 46, the liquid volume sensor 52, and the detection unit 53. The cleaning control unit 54 controls the first on-off valve 44, the pump 45, the constant flow valve 47, the second on-off valve 49, and the third on-off valve 51.

[0046] The cleaning control unit 54, like the recording control unit 15, may be configured with a processor, may be configured with a hardware circuit, or may be configured with a circuit including a combination thereof. The cleaning control unit 54 corresponds to an example of a control unit. The cleaning device 31 may be controlled by the recording control unit 15. In such a case, the recording control unit 15 corresponds to an example of a control unit.

[0047] The cleaning control unit 54 controls so as to discharge the cleaning liquid from the storage unit 35. The cleaning control unit 54 controls so as to discharge the cleaning liquid from the storage unit 35 by controlling so as to open the first on-off valve 44 and the third on-off valve 51.

[0048] In particular, the cleaning control unit 54 controls the cleaning liquid to be discharged from the storage unit 35 based on the detection result by the detection unit 53. The cleaning control unit 54 discharges the cleaning liquid when the ink concentration of the dye ink contained in the cleaning liquid stored in the storage unit 35 is high. When the ink concentration of the dye ink contained in the liquid stored in the storage unit 35 becomes high, the cleaning ability of the cleaning device 31 decreases. By discharging the cleaning liquid when the ink concentration of the dye ink contained in the liquid stored in the storage unit 35 is high, the amount of cleaning liquid used is reduced compared to a configuration in which the cleaning liquid is constantly supplied.

[0049] <Configuration of detection unit 53> Here, the configuration of the detection unit 53 will be described with reference to FIG. As shown in Fig. 2, the detection unit 53 includes an optical sensor. That is, the cleaning device 31 is equipped with an optical sensor. The detection unit 53 is equipped with a light-emitting unit 61 and a light-receiving unit 62. That is, the optical sensor is equipped with the light-emitting unit 61 and the light-receiving unit 62. The detection unit 53 may be equipped with a substrate 63. The substrate 63 is equipped with an installation surface 64. The installation surface 64 is a surface facing the first connection flow path 40. The light-emitting unit 61 and the light-receiving unit 62 are installed on the installation surface 64. That is, the light-emitting unit 61 and the light-receiving unit 62 are provided so as to face the same direction.

[0050] The light emitting unit 61 includes an element that emits light. The light emitting unit 61 includes, for example, an LED. The light emitting unit 61 emits light of a predetermined wavelength. In this manner, the light emitting unit 61 is configured to emit light.

[0051] The light receiving unit 62 includes an element that receives light and outputs a signal. The light receiving unit 62 includes, for example, a photodiode. In this manner, the light receiving unit 62 is configured to receive the light emitted from the light emitting unit 61.

[0052] The first connection flow path 40 includes a reflecting section 65. That is, the cleaning device 31 includes a reflecting section 65. The reflecting section 65 is provided in the first connection flow path 40. The reflecting section 65 is provided at a position facing the detecting section 53. The reflecting section 65 is provided at a position facing the installation surface 64. That is, the reflecting section 65 is provided at a position facing the light emitting section 61 and the light receiving section 62. The reflecting section 65 is configured to reflect light.

[0053] The first connection flow path 40 has at least light-transmitting properties between the light-emitting section 61 and the light-receiving section 62 and the reflecting section 65. Thus, the reflecting section 65 is configured to reflect light from the light-emitting section 61 to the light-receiving section 62. The light-emitting section 61 emits light toward the first connection flow path 40. After being reflected by the reflecting section 65, the light enters the light-receiving section 62. Thus, the detecting section 53 detects the transmitted light.

[0054] The reflecting unit 65 may include a reflecting sheet 66 and an installation member 67. The reflecting sheet 66 is a sheet that reflects light. The reflecting sheet 66 is attached to the installation member 67. The reflecting sheet 66 is provided on an opposing surface 68 of the installation member 67. The opposing surface 68 is a side surface. The opposing surface 68 is a surface that faces the detection unit 53. In other words, the reflecting sheet 66 is provided on the detection unit 53 side of the installation member 67.

[0055] The reflective sheet 66 is provided at a position that is a predetermined distance from the detection unit 53. The predetermined distance may be any distance that is determined so as to sufficiently reflect the light from the light-emitting unit 61 to the light-receiving unit 62. The predetermined distance may be any distance that is determined depending on the type of the detection unit 53.

[0056] The reflecting portion 65 eliminates the need for the light-emitting portion 61 and the light-receiving portion 62 to be positioned opposite each other across the first connection flow path 40. In other words, the light-emitting portion 61 and the light-receiving portion 62 do not have to be positioned to sandwich the first connection flow path 40. In one example, the light-emitting portion 61 and the light-receiving portion 62 are aligned along the first connection flow path 40. In this way, the reflecting portion 65 improves the degree of freedom regarding the positions of the light-emitting portion 61 and the light-receiving portion 62.

[0057] The dye that constitutes the dye ink dissolves in the cleaning liquid in the storage unit 35. The detection unit 53 detects the ink concentration of the dye ink by detecting the dye dissolved in the cleaning liquid. The detection unit 53 optically detects the dye contained in the cleaning liquid.

[0058] The method of optically detecting the dye contained in the cleaning solution includes a transmission method. The transmission method detects the dye based on the amount of light transmitted through the cleaning solution. In other words, the transmission method utilizes the light absorption by the dye.

[0059] In this manner, the light receiving unit 62 receives the light from the light emitting unit 61. The light receiving unit 62 receives the light from the light emitting unit 61 by reflection by the reflecting unit 65. The light receiving unit 62 receives the light from the light emitting unit 61 via the liquid in the first connection flow path 40.

[0060] The detection unit 53 can detect the ink concentration of the dye ink by evaluating the liquid stored in the first connection flow path 40. That is, the detection unit 53 detects the ink concentration of the dye ink of the liquid flowing through the first connection flow path 40.

[0061] The detection unit 53 detects the ink density of the dye ink using light with a wavelength of 400 nm or less. In particular, the detection unit 53 preferably uses light with a wavelength of 340 nm to 380 nm, and optimally uses light with a wavelength of 360 nm.

[0062] Thus, the light emitted by the light emitting section 61 includes light with a wavelength of 400 nm or less, preferably includes light with a wavelength of 340 nm or more and 380 nm or less, and optimally includes light with a wavelength of 360 nm.

[0063] The detection unit 53 may include an optical filter. The optical filter is a filter that blocks light in a predetermined frequency band. As a specific example, the optical filter may be a filter that transmits light with a wavelength of 400 nm or less and blocks light with a wavelength longer than 400 nm. The optical filter may be a filter that transmits light with a wavelength of 340 nm to 380 nm and blocks light with wavelengths other than that.

[0064] The optical filter may be disposed so as to block light of a predetermined frequency band from the light received by the light receiving unit 62. In such a case, the light receiving unit 62 may be configured to be able to receive light having a wavelength of 400 nm or less. In other words, the light receiving unit 62 may be configured to receive at least light having a wavelength of 400 nm or less.

[0065] The optical filter may be disposed so as to block light of a predetermined frequency band from the light emitted by the light-emitting unit 61. In such a case, the light-emitting unit 61 may be configured to be capable of emitting light having a wavelength of 400 nm or less. In other words, the light-emitting unit 61 may be configured to emit light having at least a wavelength of 400 nm or less.

[0066] <Characteristics of dye ink> Next, the characteristics of the dye ink will be described with reference to FIGS. 3 and 4 are graphs showing the wavelength of light and the transmittance of dye ink. In particular, FIG. 3 and FIG. 4 are graphs showing the transmittance when a liquid containing a single-color reactive dye ink and a cleaning liquid is irradiated with light. Examples of single-color reactive dye inks are black, gray, cyan, orange, yellow, red, and blue. Graphs 80 to 83 in FIG. 3 are graphs in which black, gray, cyan, and orange reactive dye inks are evaluated, respectively. Graphs 84 to 86 in FIG. 4 are graphs in which yellow, red, and blue reactive dye inks are evaluated, respectively. A liquid in which the ink concentration of a single-color reactive dye ink is 0.5% is evaluated.

[0067] 5 and 6 are graphs showing the relationship between the ink concentration of a single-color reactive dye ink and the output level. The output level is a level indicated by the amount of light received by the light receiving unit 62. Examples of single-color reactive dye ink include blue, gray, cyan, and orange. Graphs 87 to 90 in FIG. 5 and FIG. 6 are graphs that evaluate single-color blue, single-color gray, single-color cyan, and single-color orange reactive dye inks, respectively. FIG. 5 is a graph showing the output level when irradiated with light having a wavelength of 525 nm. FIG. 6 is a graph showing the output level when irradiated with light having a wavelength of 660 nm.

[0068] FIG. 7 is a graph showing the relationship between the transmittance of reactive dye ink and the coefficient of determination, and the relationship between the transmittance of reactive dye ink and the slope of the ink concentration of reactive dye ink. The slope of the ink concentration of reactive dye ink indicates the slope between the ink concentration of reactive dye ink and the output belt. Graph 91 in FIG. 7 is a graph showing the relationship between the transmittance of reactive dye ink and the coefficient of determination. Graph 92 in FIG. 7 is a graph showing the relationship between the transmittance of reactive dye ink and the slope of the ink concentration of reactive dye ink.

[0069] Fig. 8 is a graph showing the relationship between ink density and output level. Fig. 8 is a graph when the coefficient of determination is set to 1. Graph 93 in Fig. 8 is a graph in which a black monochromatic reactive dye ink is evaluated. Graph 94 in Fig. 8 is a graph in which a cyan monochromatic reactive dye ink is evaluated.

[0070] 3 and 4, in reactive dye ink, the transmittance to the wavelength of light differs depending on the color of the reactive dye ink. In other words, in dye ink, the absorbency to the wavelength of light differs depending on the color of the dye ink.

[0071] 5 and 6, in the case of reactive dye ink, the ink concentration of the reactive dye ink and the output level are inversely proportional to each other. In other words, the higher the ink concentration of the reactive dye ink, the lower the output level. Thus, the higher the ink concentration of the dye ink, the smaller the amount of light received by the light receiving unit 62.

[0072] In particular, the greater the ink concentration of the reactive dye ink, the greater the linearity of the graph. As the linearity of the graph increases, the error in the relationship between the ink concentration of the dye ink and the output level decreases. Therefore, as the linearity of the graph increases, the accuracy of detecting the ink concentration of the dye ink based on the output level increases.

[0073] In addition, the output level for the ink density of the reactive dye ink differs depending on the color of the reactive dye ink, and when the wavelength of the light irradiated onto the liquid containing the reactive dye ink and the cleaning agent differs, the output level for the ink density of the reactive dye ink differs.

[0074] As shown in FIG. 7, in order to improve the detection accuracy of the ink concentration, it is appropriate to satisfy both the first criterion and the second criterion. The first criterion is that the coefficient of determination is 0.8 or more. The second criterion is that the slope of the ink concentration is 80 or more. The second criterion corresponds to the slope of the ink concentration where the output level decreases by 40% when the ink concentration is 0.5%. In such a case, an appropriate condition for the ink transmittance is 8% to 50%. In other words, an appropriate condition for the ink transmittance ratio is 0.08 to 0.5.

[0075] 3 and 4, there is a tendency that there is less variation in the ink transmittance ratio for each color of ink if the light has a wavelength of 340 nm or more and 380 nm or less. For this reason, it is optimal for the light emitted by the light-emitting unit 61 to include light with a wavelength of 340 nm or more and 380 nm or less. The light emitted by the light-emitting unit 61 may include ultraviolet light, such as light with a wavelength of 400 nm or less. The light emitted by the light-emitting unit 61 may also include purple visible light, such as light with a wavelength of 380 nm or more and 430 nm or less.

[0076] As shown in Fig. 8, when light with a wavelength of 360 nm is used, the linearity of both graphs 93 and 94 is high. Graph 93 is a monochrome reactive dye ink, which is an example that tends to have a low transmittance. Graph 94 is a monochrome reactive dye ink, which is an example that tends to have a low transmittance. In this way, the linearity of the graphs is high for dye inks of each color.

[0077] For this reason, the detection unit 53 detects the amount of light received by the light receiving unit 62 using light with a wavelength of 400 nm or less. This makes it possible to detect the ink concentration of the dye ink. In particular, it is optimal for the detection unit 53 to use light with a wavelength of 360 nm, and it is preferable to use light with a wavelength of 340 nm to 380 nm, which is an allowable range centered around 360 nm.

[0078] <Control by cleaning control unit 54> The cleaning control unit 54 compares the detection result of the detection unit 53 with a threshold value to determine whether or not to drain the cleaning liquid. When the ink concentration of the dye ink is equal to or higher than the threshold value, the cleaning control unit 54 drains the cleaning liquid from the storage unit 35. At this time, the cleaning control unit 54 opens the first on-off valve 44 and the third on-off valve 51 to drain the cleaning liquid from the storage unit 35. After completing the drainage of the cleaning liquid, the cleaning control unit 54 closes the third on-off valve 51 and opens the second on-off valve 49 to supply the cleaning liquid to the storage unit 35. This replaces the cleaning liquid.

[0079] When discharging the cleaning liquid, the cleaning control unit 54 may determine whether the recording device 11 is recording or not. The cleaning control unit 54 may determine whether the recording device 11 is recording or not by communicating with the recording control unit 15. The cleaning control unit 54 may determine whether the recording device 11 is recording or not by receiving an operation from a user. When the recording device 11 is recording, it is preferable that the cleaning liquid is stored in the cleaning tank 36. Therefore, when the recording device 11 is recording, the cleaning control unit 54 discharges the cleaning liquid from the storage tank 39 by opening the second opening / closing valve 49 with the first opening / closing valve 44 closed. As a result, the cleaning liquid is retained in the cleaning tank 36, while the cleaning liquid is replaced in the storage tank 39.

[0080] <Actions and Effects of the First Embodiment> The operation and effects of the first embodiment will be described. (1) The cleaning control unit 54 controls the cleaning liquid to be discharged from the storage unit 35 based on the detection result by the detection unit 53. The light emitted by the light-emitting unit 61 includes light with a wavelength of 400 nm or less. With this configuration, even when dye ink is the target, it is possible to improve the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid by using light with a wavelength that satisfies appropriate conditions. Therefore, by accurately detecting the concentration of the ink mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0081] (2) The wavelength of the light emitted by the light-emitting unit 61 includes light having a wavelength of 340 nm or more and 380 nm or less. With this configuration, even when dye ink is the target, the accuracy of detecting the ink concentration of the dye ink mixed into the cleaning liquid can be further improved by using light having a wavelength that satisfies the optimal conditions. Therefore, by accurately detecting the concentration of the ink mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0082] (3) The cleaning device 31 may include a reflecting section 65 provided on an opposing surface 68 that faces an installation surface 64 on which the light-emitting section 61 and the light-receiving section 62 are installed. With this configuration, the arrangement of the light-emitting section 61 and the light-receiving section 62 can be adjusted by the reflecting section 65. This makes it possible to further improve the detection accuracy of the ink concentration of dye ink mixed into the cleaning liquid, even when dye ink is used as the target. Therefore, by accurately detecting the concentration of ink mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0083] (4) Furthermore, the light-receiving unit 62 can receive the light from the light-emitting unit 61 even if the light-emitting unit 61 and the light-receiving unit 62 are not opposed to each other. This allows the light-emitting unit 61 and the light-receiving unit 62 to be arranged together. This allows the cleaning device 31 to be made smaller.

[0084] (5) The storage unit 35 includes a cleaning tank 36, a storage tank 39, and a first connection flow path 40. The cleaning tank 36 is a tank in which the cleaning unit 32 is immersed in the stored cleaning liquid. The first connection flow path 40 is provided to connect the cleaning tank 36 and the storage tank 39. The detection unit 53 is provided in the first connection flow path 40. With this configuration, the ink concentration of the dye ink can be detected in the first connection flow path 40, which tends to have a smaller diameter than the cleaning tank 36 and the storage tank 39. This makes it possible to further improve the detection accuracy of the ink concentration of the dye ink mixed in the cleaning liquid, even when the dye ink is the subject. Therefore, by accurately detecting the ink concentration mixed in the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0085] (6) The cleaning device 31 includes a pump 45 that circulates the cleaning liquid between the cleaning tank 36 and the storage tank 39 through the first connection flow path 40 and the second connection flow path 41. With this configuration, the ink concentration of the dye ink contained in the cleaning liquid is more likely to become uniform by circulating the cleaning liquid between the cleaning tank 36 and the storage tank 39. This makes it possible to further improve the accuracy of detecting the ink concentration of the dye ink mixed into the cleaning liquid, even when the dye ink is the target. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0086] [Example of change] This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction.

[0087] The detection unit 53 may be provided in the storage unit 35. The detection unit 53 may also be provided in the storage tank 39. The detection unit 53 may also be provided in the cleaning tank 36. In this case, it is possible to detect the ink concentration of the dye ink in the cleaning tank 36 in which the cleaning unit 32 is immersed in the cleaning liquid. This makes it possible to further improve the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid, even when the dye ink is the subject of the detection. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0088] When the detection unit 53 is provided in the cleaning tank 36, the cleaning device 31 does not need to include the storage tank 39. In this case, the cleaning device 31 may be configured so that the discharge flow path 50 is directly connected to the cleaning tank 36. This allows the cleaning device 31 to configure the storage unit 35 with a minimum of functions. This allows the cleaning device 31 to be made smaller and less expensive.

[0089] The reflecting unit 65 does not have to be configured to have the reflecting sheet 66 attached to the installation member 67 as long as it can reflect the light from the light-emitting unit 61 to the light-receiving unit 62. The reflecting unit 65 may have the reflecting sheet 66 and the installation member 67 integrally configured as long as it can reflect the light from the light-emitting unit 61 to the light-receiving unit 62.

[0090] The diameter of the first connection flow path 40 may be reduced in the region where the detection unit 53 is provided. The light emitter 61 and the light receiver 62 may be provided at positions sandwiching the first connection flow path 40. In this case, the cleaning device 31 does not need to include the reflector 65.

[0091] The present invention can be applied not only to the cleaning device 31 but also to a recording device 11 having the functions of the cleaning device 31. The recording device 11 may have some of the functions of the cleaning device 31, or may have all of the functions of the cleaning device 31.

[0092] The term "at least any" as used herein means one or more of the desired options. As an example, the term "at least any" as used herein means only one option or both options if the number of options is two. As another example, the term "at least any" as used herein means only one option or any combination of two or more options if the number of options is three or more.

[0093] [Note] The technical ideas and their effects that can be understood from the above-mentioned embodiment and modified examples will be described below. The technical ideas and their effects can be combined with each other to the extent that there is no technical contradiction.

[0094] (A) A cleaning device includes a storage section that stores cleaning liquid used to clean a conveyor belt that transports a medium, an optical sensor that detects the ink concentration of dye ink mixed into the cleaning liquid stored in the storage section, and a control section that controls the cleaning liquid to be discharged from the storage section, wherein the optical sensor has an emitter that emits light and a light receiver that receives the light emitted from the emitter, and the control section controls the cleaning liquid to be discharged from the storage section based on the detection result by the optical sensor, and the light emitted by the light emitter includes light with a wavelength of 400 nm or less.

[0095] According to this configuration, even when dye ink is used, it is possible to improve the accuracy of detecting the ink concentration of the dye ink mixed into the cleaning liquid by using light of a wavelength that satisfies appropriate conditions. Therefore, by detecting the ink concentration of the ink mixed into the cleaning liquid with high accuracy, the cleaning liquid can be appropriately discharged.

[0096] (B) In the above cleaning device, the wavelength of the light emitted by the light emitting section may include light with a wavelength of 340 nm or more and 380 nm or less. With this configuration, even when dye ink is used, the ink concentration of the dye ink mixed into the cleaning liquid can be detected with even greater accuracy by using light with a wavelength that satisfies optimal conditions. Therefore, by detecting the ink concentration of the dye ink mixed into the cleaning liquid with high accuracy, the cleaning liquid can be appropriately discharged.

[0097] (C) The cleaning device may further include a reflecting section provided on an opposing surface that faces an installation surface on which the light-emitting section and the light-receiving section are installed. According to this configuration, the position of the light emitting unit and the light receiving unit can be adjusted by the reflecting unit. This makes it possible to further improve the accuracy of detecting the ink concentration of the dye ink mixed into the cleaning liquid, even when the dye ink is used as the target. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0098] In addition, the light receiving section can receive the light from the light emitting section even if the light emitting section and the light receiving section are not opposed to each other. This allows the light emitting section and the light receiving section to be arranged together, which contributes to the miniaturization of the cleaning device.

[0099] (D) The above-mentioned cleaning device includes a cleaning section that cleans the conveying belt with cleaning liquid, the storage section including a cleaning tank, a storage tank, and a connecting flow path, the cleaning tank being a tank in which the cleaning section is immersed in the stored cleaning liquid, the connecting flow path being arranged to connect the cleaning tank and the storage tank, and the optical sensor being provided in the connecting flow path.

[0100] According to this configuration, the ink concentration of the dye ink can be detected in the connecting flow path, which tends to have a smaller diameter than the cleaning tank and the storage tank. This makes it possible to further improve the accuracy of detecting the ink concentration of the dye ink mixed into the cleaning liquid, even when the dye ink is the target. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0101] (E) The above-mentioned cleaning device may include a cleaning section that cleans the conveying belt with cleaning liquid, the storage section including a cleaning tank that stores the cleaning liquid, the cleaning tank being a tank in which the cleaning section is immersed in the stored cleaning liquid, and the optical sensor may be provided in the cleaning tank.

[0102] According to this configuration, an optical sensor can be provided in the cleaning tank in which the cleaning unit is immersed in the cleaning liquid. This can further improve the accuracy of detecting the ink concentration of the dye ink mixed into the cleaning liquid, even when the dye ink is used as the target. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0103] (F) A recording device includes the above-mentioned cleaning device, a conveying unit having the conveying belt, and a recording unit that performs recording by ejecting dye ink onto a medium conveyed by the conveying unit. With this configuration, the same effect as (A) can be achieved. [Explanation of symbols]

[0104] A1...conveying direction, A2...opposite direction, 11...recording device, 12...recording section, 13...nozzle, 14...nozzle surface, 15...recording control section, 21...conveying section, 22...first conveying roller, 23...second conveying roller, 24...driving source, 25...conveying belt, 26...inner circumferential surface, 27...outer circumferential surface, 28...pressing section, 31...cleaning device, 32...cleaning section, 33...cleaning roller, 34...cleaning blade, 35...storage section, 36...cleaning tank, 37...immersion tank, 38...support tank, 39...storage tank, 40...first connection Flow path, 41...second connecting flow path, 42...cleaning filter, 43...storage filter, 44...first on-off valve, 45...pump, 46...flow meter, 47...constant flow rate valve, 48...supply flow path, 49...second on-off valve, 50...discharge flow path, 51...third on-off valve, 52...liquid level sensor, 53...detection unit, 54...cleaning control unit, 61...light emitting unit, 62...light receiving unit, 63...substrate, 64...mounting surface, 65...reflecting unit, 66...reflective sheet, 67...mounting member, 68...opposing surface, 80-93...graph, 99...medium.

Claims

1. a reservoir for storing a cleaning liquid for cleaning a conveyor belt that conveys a medium; an optical sensor for detecting an ink concentration of the dye ink mixed in the cleaning liquid stored in the storage section; A control unit that controls the cleaning liquid to be discharged from the storage unit; Equipped with The optical sensor includes a light emitting unit that emits light and a light receiving unit that receives the light emitted from the light emitting unit, The control unit controls the cleaning liquid to be discharged from the storage unit based on a detection result by the optical sensor, The light emitted by the light emitting unit includes light with a wavelength of 400 nm or less. A cleaning device characterized by:

2. 2. The cleaning apparatus according to claim 1, The wavelength of the light emitted by the light emitting unit includes light with a wavelength of 340 nm or more and 380 nm or less. A cleaning device characterized by:

3. 2. The cleaning apparatus according to claim 1, a reflector provided on an opposing surface facing an installation surface on which the light emitting unit and the light receiving unit are installed, A cleaning device characterized by:

4. 2. The cleaning apparatus according to claim 1, a cleaning unit that cleans the conveyor belt with a cleaning liquid; The reservoir includes a cleaning tank, a storage tank, and a connecting flow path; The cleaning tank is a tank in which the cleaning unit is immersed in a cleaning liquid stored therein, the connection flow path is provided to connect the cleaning tank and the storage tank, The optical sensor is provided in the connecting flow path. A cleaning device characterized by:

5. 2. The cleaning apparatus according to claim 1, a cleaning unit that cleans the conveyor belt with a cleaning liquid; the storage unit includes a cleaning tank that stores a cleaning liquid, The cleaning tank is a tank in which the cleaning unit is immersed in a cleaning liquid stored therein, The optical sensor is provided in the cleaning tank. A cleaning device characterized by:

6. A cleaning device according to any one of claims 1 to 5, A conveying section having the conveying belt; a recording unit that performs recording by ejecting dye ink onto the medium transported by the transport unit; Equipped with A recording apparatus comprising:

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