Cleaning apparatus and recording apparatus

Abstract

The invention provides a cleaning device and a recording device which can accurately detect the concentration of ink mixed in cleaning liquid so as to appropriately discharge the cleaning liquid. The cleaning device is provided with: a storage unit that stores a cleaning liquid that cleans a conveyor belt that conveys a medium; an optical sensor that detects the ink concentration of the dye ink mixed in the cleaning liquid stored in the storage unit; and a control unit that performs control so as to discharge the cleaning liquid from the storage unit. The optical sensor has a light-emitting unit that emits light, and a light-receiving unit that receives light emitted from the light-emitting unit. The control unit performs control such that the cleaning liquid is discharged from the storage unit on the basis of a detection result obtained by the optical sensor. The light emitted by the light-emitting unit includes light having a wavelength of 400 nm or less.

Description

Technical Field

[0001] The present invention relates to a cleaning device and a recording device. Background Art

[0002] In Patent Document 1, a cleaning device for cleaning a conveyor belt that conveys a medium with a cleaning liquid is described. In the cleaning device, ink is mixed into the cleaning liquid during the process of cleaning the conveyor belt. The cleaning device detects the ink concentration of the ink mixed into the cleaning liquid based on the light transmittance of the cleaning liquid. When the ink concentration is high, the cleaning device discharges the cleaning liquid.

[0003] However, in such a cleaning device, it is not easy to accurately detect the ink concentration based on the light transmittance of the cleaning liquid for ink that does not have particles in the cleaning liquid due to dissolution. Thus, it is desired to appropriately discharge the cleaning liquid by accurately detecting the ink concentration mixed into the cleaning liquid.

[0004] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2008 - 213394 Summary of the Invention

[0005] The cleaning device for solving the above problems includes: a storage unit that stores a cleaning liquid for cleaning a conveyor belt that conveys a medium; an optical sensor that detects the ink concentration of dye ink mixed into the cleaning liquid stored in the storage unit; a control unit that controls to discharge the cleaning liquid from the storage unit. The optical sensor has 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 to discharge the cleaning liquid from the storage unit based on the detection result obtained by the optical sensor. The light emitted from the light emitting unit includes light having a wavelength of 400 nm or less.

[0006] The recording device for solving the above problems includes: the above cleaning device; a conveying unit that has the conveyor belt; and a recording unit that performs recording by ejecting dye ink onto a medium conveyed by the conveying unit. Brief Description of the Drawings

[0007] Figure 1 A schematic diagram showing a recording device including the cleaning device in the first embodiment.

[0008] Figure 2 A schematic diagram showing the detection unit in the first embodiment.

[0009] Figure 3 A graph showing the wavelength of light and the permeability of dye ink in the first embodiment.

[0010] Figure 4 A chart showing the wavelength of light and the permeability of the dye ink in the first embodiment.

[0011] Figure 5 A chart showing the relationship between the ink concentration and the output level in the first embodiment.

[0012] Figure 6 A chart showing the relationship between the ink concentration and the output level in the first embodiment.

[0013] Figure 7 A chart 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 slope of the ink concentration of the dye ink in the first embodiment.

[0014] Figure 8 A chart showing the relationship between the ink concentration and the output level in the first embodiment. Detailed implementation mode

[0015] First embodiment

[0016] Hereinafter, an embodiment of a recording apparatus including a cleaning device will be described.

[0017] Structure of the recording apparatus 11

[0018] As Figure 1 shown, the recording apparatus 11 is an inkjet printer that records an image by ejecting a liquid onto a medium. The medium can be, for example, cloth, paper, etc. The image can also be text, a photo, etc. The liquid can be, for example, a dye ink. The liquid can also include a reactive dye ink. The liquid can also include an acid dye ink. That is, the liquid can include a reactive dye ink or an acid dye ink.

[0019] The dye ink is an ink containing a dye in a solvent. The dye ink includes an ink that causes no particles to exist in the cleaning liquid due to dissolution in the cleaning liquid. The dye ink can include, for example, inks such as black, blue - green, yellow, magenta, red, orange, green, light black, etc.

[0020] Structure of the recording unit 12

[0021] The recording device 11 includes a recording unit 12. The recording unit 12 is configured to eject liquid onto the medium 99. The recording unit 12 is configured to eject liquid onto the medium 99 conveyed by the conveying unit 21, which will be described in detail later. Thus, 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 with one or more nozzles 13 opened thereon. The recording unit 12 ejects liquid from the nozzles 13. The recording unit 12 may be a serial head that scans relative to the medium 99. The recording unit 12 may also be a line head that can eject liquid over the entire width of the medium 99 at once.

[0022] Structure of the conveying unit 21

[0023] The recording device 11 includes a conveying unit 21. The conveying unit 21 is configured to convey the medium 99. During the conveyance of the medium 99 by the conveying unit 21, liquid is ejected from the recording unit 12 onto the medium 99.

[0024] The conveying unit 21 is configured to convey the medium 99 in the conveying direction A1. The conveying unit 21 has a plurality of conveying rollers. In one example, the conveying unit 21 has a first conveying roller 22 and a second conveying roller 23. The first conveying roller 22 is located upstream of the recording unit 12 in the conveying direction A1. The second conveying roller 23 is located downstream of the recording unit 12 in the conveying direction A1.

[0025] The conveying unit 21 has a drive source 24. The drive source 24 is, for example, an electric motor. The drive source 24 is connected to at least one of the plurality of conveying rollers. In one example, the drive source 24 is connected to the first conveying roller 22. By the drive source 24, the first conveying roller 22 is rotated.

[0026] The conveying unit 21 has a conveyor belt 25. The conveyor belt 25 is wound around the plurality of conveying rollers. In one example, the conveyor belt 25 is wound around the first conveying roller 22 and the second conveying roller 23. The conveyor belt 25 rotates along the first conveying roller 22 and the second conveying roller 23 by the first conveying roller 22 being rotated by the drive source 24. In Figure 1 this case, the conveyor belt 25 rotates counterclockwise. Thus, the conveyor belt 25 conveys the medium 99. The conveyor belt 25 supports the medium 99 on which an image has been recorded by the recording unit 12.

[0027] The conveyor belt 25 includes a portion that moves in the conveying direction A1 and a portion that moves in the opposite direction A2 opposite to the conveying direction A1. The conveyor belt 25 conveys the medium 99 through the portion that moves in the conveying direction A1. The portion that moves in the opposite direction A2 is cleaned by the cleaning device 31 described later.

[0028] The conveyor belt 25 has an inner circumferential surface 26 and an outer circumferential surface 27. The inner circumferential surface 26 is the surface that contacts a plurality of conveyor rollers. In one example, the inner circumferential surface 26 contacts the first conveyor roller 22 and the second conveyor roller 23. The outer circumferential surface 27 is the surface that contacts the medium 99. The outer circumferential surface 27 is the surface that supports the medium 99. The outer circumferential surface 27 faces the nozzle surface 14.

[0029] The conveyor belt 25 is configured to enable the medium 99 to adhere to the conveyor belt 25. Specifically, the medium 99 adheres to the outer circumferential surface 27. Thereby, the medium 99 is conveyed in a stable posture. In one example, the conveyor belt 25 is an adhesive tape coated with an adhesive. The adhesive is coated on the outer circumferential surface 27. In this case, the medium 99 adheres to the outer circumferential surface 27 through the adhesive. It is not limited to the adhesive. For example, the medium 99 can also be adhered to the outer circumferential surface 27 by suction force, electrostatic force, intermolecular force, etc. After the medium 99 is recorded with an image by the recording unit 12, the medium 99 is peeled off from the outer circumferential surface 27, for example, by being pulled by another device. The conveying unit 21 may also have a peeling unit for peeling the medium 99 from the outer circumferential surface 27. In this case, the peeling unit is, for example, a roller around which the medium 99 is wound.

[0030] The conveying unit 21 may also have a pressing unit 28. The pressing unit 28 is configured to press the medium 99 against the conveyor belt 25. In one example, the pressing unit 28 is a roller. By pressing the medium 99 against the conveyor belt 25 by the pressing unit 28, the medium 99 adheres to the outer circumferential surface 27.

[0031] In the conveyor belt 25, there is a situation where, along with the recording unit 12 recording an image on the medium 99, the dye ink ejected as a liquid adheres to the outer circumferential surface 27. If the conveyor belt 25 continues to convey the medium 99 in a state where the dye ink adheres to the outer circumferential surface 27, the medium 99 may get dirty.

[0032] Structure of the recording control unit 15

[0033] 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 conveying unit 21. The recording control unit 15 may be constituted by one or more processors. The processor executes various processes in accordance with a computer program. The recording control unit 15 may be constituted by 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 constituted by a circuit including a combination of a processor and a hardware circuit. The processor includes a CPU and memories such as a RAM and a ROM. The memory stores program codes or instructions configured to cause the CPU to execute processes. The memory, i.e., the computer-readable medium, includes all readable media that can be accessed by a general or dedicated computer.

[0034] Structure of the cleaning device 31

[0035] 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. Specifically, the cleaning device 31 cleans the outer peripheral surface 27 with the cleaning liquid. The cleaning device 31 removes the dye ink attached to the outer peripheral surface 27 with the cleaning liquid. The cleaning liquid makes the dye ink easier to fall off from the conveyor belt 25. Thus, the cleaning liquid is a liquid for cleaning the conveyor belt 25. In one example, the cleaning liquid is water.

[0036] Structure of the cleaning unit 32

[0037] 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. Specifically, the cleaning unit 32 contacts the outer peripheral surface 27. The cleaning unit 32 contacts a portion of the conveyor belt 25 located in the opposite direction A2. That is, the cleaning unit 32 contacts the conveyor belt 25 after the medium 99 is peeled off.

[0038] 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 contact the conveyor belt 25 while rotating. The cleaning rollers 33 may rotate idly relative to the conveyor belt 25. That is, the cleaning rollers 33 may rotate idly clockwise in Figure 1 The cleaning rollers 33 may be driven to rotate in a manner that opposes the rotation of the conveyor belt 25. That is, the cleaning rollers 33 may rotate counterclockwise in Figure 1 In this case, the contact resistance between the cleaning rollers 33 and the conveyor belt 25 increases. Therefore, it becomes easier to remove the dye ink from the conveyor belt 25.

[0039] The cleaning roller 33 contacts the conveyor belt 25 in a state wetted by the cleaning liquid. Thereby, the conveyor belt 25 is wetted by the cleaning liquid. Therefore, it becomes easier to remove the dye ink from the conveyor belt 25. The cleaning roller 33 is, for example, a brush roller. The cleaning roller 33 may also be a sponge roller.

[0040] 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 wetted by the cleaning liquid. The cleaning blade 34 contacts the outer peripheral surface 27 wetted by the cleaning liquid. The cleaning blade 34 scrapes off the dye ink and the cleaning liquid attached to the conveyor belt 25 together. The cleaning blade 34 contacts the conveyor belt 25 after the cleaning roller 33 contacts the conveyor belt 25. Therefore, the cleaning blade 34 is located in the opposite direction A2 compared to the cleaning roller 33.

[0041] Structure of the storage unit 35

[0042] The cleaning device 31 includes a storage unit 35. The storage unit 35 is configured to store the cleaning liquid. The storage unit 35 holds the cleaning unit 32. The storage unit 35 is configured to store the cleaning liquid supplied to the cleaning unit 32. The cleaning unit 32 uses the cleaning liquid stored in the storage unit 35 to clean the conveyor belt 25. The cleaning liquid stored in the storage unit 35 will gradually become dirty as the cleaning unit 32 cleans the conveyor belt 25. That is, in the cleaning liquid stored in the storage unit 35, the dye ink attached to the conveyor belt 25 may sometimes be mixed in. Thus, the storage unit 35 may sometimes store the cleaning liquid mixed with the dye ink. Therefore, the cleaning device 31 needs to appropriately replace the cleaning liquid stored in the storage unit 35.

[0043] The storage unit 35 has a cleaning tank 36. The cleaning tank 36 is a tank for storing the cleaning liquid. The cleaning tank 36 is located at a position opposite to the outer peripheral surface 27. The cleaning tank 36 holds the cleaning unit 32. As the cleaning roller 33 cleans the conveyor belt 25, the dye ink will flow into the cleaning tank 36. That is, the cleaning tank 36 stores the cleaning liquid after being used by the cleaning unit 32.

[0044] The cleaning tank 36 has an immersion tank 37. The immersion tank 37 is a tank for storing a predetermined amount of cleaning liquid. The immersion tank 37 holds the cleaning roller 33. The immersion tank 37 holds the cleaning roller 33 in such a way that the cleaning roller 33 is immersed in the stored cleaning liquid. That is, the cleaning tank 36 is a tank for immersing the cleaning unit 32 in the stored cleaning liquid. As the cleaning roller 33 cleans the conveyor belt 25, the dye ink will flow into the immersion tank 37. That is, the immersion tank 37 stores the cleaning liquid after being used by the cleaning unit 32.

[0045] The cleaning tank 36 has a support tank 38. The support tank 38 supports the dipping tank 37. Specifically, the support tank 38 houses the dipping tank 37. The support tank 38 receives the cleaning liquid that overflows from the dipping tank 37.

[0046] The support tank 38 supports the cleaning blade 34. The support tank 38 receives the cleaning liquid that flows down along the cleaning blade 34. Along with the cleaning of the conveyor belt 25 by the cleaning blade 34, the dye ink flows into the support tank 38.

[0047] The reservoir part 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 recovering the cleaning liquid from the cleaning tank 36. The storage tank 39 can also be a tank for circulating the cleaning liquid stored in the cleaning tank 36. The storage tank 39 stores the cleaning liquid after it is used by the cleaning part 32.

[0048] The reservoir part 35 has connecting channels. The reservoir part 35 can also have a plurality of connecting channels. In one example, the reservoir part 35 has a first connecting channel 40 and a second connecting channel 41. The first connecting channel 40 and the second connecting channel 41 are connecting channels connected to the cleaning tank 36 and the storage tank 39. Specifically, the first connecting channel 40 is connected to the support tank 38 and the storage tank 39. The second connecting channel 41 is connected to the dipping tank 37 and the storage tank 39.

[0049] The cleaning liquid flows from the cleaning tank 36 through the first connecting channel 40 to the storage tank 39. Specifically, the cleaning liquid flows from the support tank 38 through the first connecting channel 40 to the storage tank 39. The cleaning liquid flows from the storage tank 39 through the second connecting channel 41 to the cleaning tank 36. Specifically, the cleaning liquid flows from the storage tank 39 through the second connecting channel 41 to the dipping tank 37. Thus, in the reservoir part 35, the cleaning liquid circulates between the cleaning tank 36 and the storage tank 39. Thereby, it is easy to make the concentration of the dye ink contained in the cleaning liquid uniform.

[0050] The cleaning device 31 can also be provided with one or more filters. The cleaning device 31 is provided with a cleaning filter 42 and a storage filter 43. The filters trap dust, fine hairs, etc. in the cleaning liquid. The cleaning filter 42 is installed on the first connecting channel 40. Specifically, the cleaning filter 42 is located at the end of the first connecting channel 40 that is connected to the cleaning tank 36. The cleaning filter 42 traps foreign substances from the cleaning liquid flowing from the cleaning tank 36 to the storage tank 39. The storage filter 43 is installed on the first connecting channel 40. Specifically, the storage filter 43 is located at the end of the first connecting channel 40 that is connected to the storage tank 39. The storage filter 43 traps foreign substances from the cleaning liquid flowing from the cleaning tank 36 to the storage tank 39.

[0051] The cleaning device 31 is provided with a first on-off valve 44. The first on-off valve 44 is, for example, an electromagnetic valve. The first on-off valve 44 is located on the first connection flow path 40. By opening the first on-off valve 44, the cleaning liquid can flow from the cleaning tank 36 to the storage tank 39.

[0052] The cleaning device 31 is provided with a pump 45. The pump 45 circulates the cleaning liquid in the storage section 35. The pump 45 circulates the cleaning liquid through the first connection flow path 40 and the second connection flow path 41 in the cleaning tank 36 and the storage tank 39. In this way, 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 on the second connection flow path 41. The pump 45 may also be located on the first connection flow path 40.

[0053] The cleaning device 31 is provided with 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 in 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 on the second connection flow path 41. Specifically, the flowmeter 46 is located between the pump 45 and the storage tank 39 in the second connection flow path 41. The flowmeter 46 may also be located on the first connection flow path 40.

[0054] The cleaning device 31 is provided with a constant flow valve 47. The constant flow valve 47 is configured to maintain the flow rate of the cleaning liquid flowing in the storage section 35 as constant. The constant flow valve 47 is a so-called choke valve. The constant flow valve 47 maintains the flow rate of the cleaning liquid circulating in the cleaning tank 36 and the storage tank 39 as constant. In one example, the constant flow valve 47 is located on the second connection flow path 41. Specifically, the constant flow valve 47 is located between the pump 45 and the cleaning tank 36 in the second connection flow path 41. The constant flow valve 47 may also be located on the first connection flow path 40.

[0055] The cleaning device 31 is provided with a supply flow path 48. The supply flow path 48 is a flow path for supplying the cleaning liquid. 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 section 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 pipe. When the cleaning liquid in the storage section 35 decreases due to evaporation of the cleaning liquid, discharge of the cleaning liquid, etc., the cleaning liquid is supplied from the supply flow path 48 to the storage section 35.

[0056] The cleaning device 31 is provided with a second on-off valve 49. The second on-off valve 49 is, for example, an electromagnetic valve. The second on-off valve 49 is located in the supply flow path 48. By opening the second on-off valve 49, the cleaning liquid is supplied to the storage section 35.

[0057] The cleaning device 31 is provided with a discharge channel 50. The discharge channel 50 is a channel for discharging the cleaning liquid. The cleaning liquid is discharged from the cleaning device 31 through the discharge channel 50. In one example, the discharge channel 50 is connected to the storage tank 39. The discharge channel 50 is connected, for example, to a processing device for treating waste liquid, a waste liquid tank for storing waste liquid, etc. When the cleaning liquid becomes dirty due to dye ink, the cleaning liquid is discharged from the storage part 35 through the discharge channel 50.

[0058] The cleaning device 31 is provided with a third on-off valve 51. The third on-off valve 51 is, for example, an electromagnetic valve. The third on-off valve 51 is located on the discharge channel 50. By opening the third on-off valve 51, the cleaning liquid is discharged from the storage part 35.

[0059] The cleaning device 31 may also be provided with a liquid volume sensor 52. The liquid volume sensor 52 is a sensor for measuring the amount of cleaning liquid stored in the storage part 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 part 35 at a constant amount through 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 channel 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 channel 48.

[0060] The cleaning device 31 is provided with a detection part 53. The detection part 53 is configured to detect the ink concentration of the dye ink mixed into the cleaning liquid stored in the storage part 35. The detection part 53 is provided on the first connection channel 40. The detection part 53 may also be provided on the second connection channel 41. That is, the detection part 53 is provided in the connection channel. Hereinafter, the ink concentration of the dye ink mixed into the cleaning liquid stored in the storage part 35 is only expressed as the ink concentration of the dye ink.

[0061] The cleaning device 31 is provided with a cleaning control part 54. The cleaning control part 54 controls the cleaning device 31. The cleaning control part 54 receives the output results from the flow meter 46, the liquid volume sensor 52, and the detection part 53. The cleaning control part 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.

[0062] The cleaning control unit 54 can be constituted by a processor in the same manner as the recording control unit 15, can be constituted by a hardware circuit, or can be constituted by a circuit including a combination of these structures. The cleaning control unit 54 corresponds to an example of the control unit. The cleaning device 31 can also be controlled by the recording control unit 15. In such a case, the recording control unit 15 corresponds to an example of the control unit.

[0063] The cleaning control unit 54 controls the cleaning liquid to be discharged from the storage unit 35. The cleaning control unit 54 controls the cleaning liquid to be discharged from the storage unit 35 by implementing control to open the first on-off valve 44 and the third on-off valve 51.

[0064] In particular, the cleaning control unit 54 controls the cleaning liquid to be discharged from the storage unit 35 based on the detection result obtained 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 large. If the ink concentration of the dye ink contained in the liquid stored in the storage unit 35 becomes large, the cleaning ability of the cleaning device 31 will decrease. By discharging the cleaning liquid when the ink concentration of the dye ink contained in the liquid stored in the storage unit 35 is large, the amount of cleaning liquid used can be reduced compared to a structure that continuously supplies the cleaning liquid without interruption.

[0065] Structure of the detection unit 53

[0066] Here, refer to Figure 2 to describe the structure of the detection unit 53.

[0067] As Figure 2 shown, the detection unit 53 includes an optical sensor. That is, the cleaning device 31 is provided with an optical sensor. The detection unit 53 includes a light emitting unit 61 and a light receiving unit 62. That is, the optical sensor includes a light emitting unit 61 and a light receiving unit 62. The detection unit 53 may include a substrate 63. The substrate 63 has a setting surface 64. The setting surface 64 is a surface facing the first connection flow path 40. The light emitting unit 61 and the light receiving unit 62 are provided on the setting surface 64. That is, the light emitting unit 61 and the light receiving unit 62 are provided in a manner facing the same direction.

[0068] The light emitting unit 61 includes an element that emits light. The light emitting unit 61 includes, for example, an LED (light emitting diode). The light emitting unit 61 emits light of a predetermined wavelength. In this way, the light emitting unit 61 is constituted to emit light.

[0069] The light-receiving unit 62 includes an element that receives light to output a signal. The light-receiving unit 62 includes, for example, a photodiode. Thus, the light-receiving unit 62 is configured to receive the light emitted from the light-emitting unit 61.

[0070] The first connection channel 40 has a reflection portion 65. That is, the cleaning device 31 has a reflection portion 65. The reflection portion 65 is provided in the first connection channel 40. The reflection portion 65 is provided at a position facing the detection unit 53. The reflection portion 65 is provided at a position facing the setting surface 64. That is, the reflection portion 65 is provided at a position facing the light-emitting unit 61 and the light-receiving unit 62. The reflection portion 65 is configured to reflect light.

[0071] The first connection channel 40 is at least translucent between the light-emitting unit 61 and the light-receiving unit 62 and the reflection portion 65. Thus, the reflection portion 65 is configured to reflect the light from the light-emitting unit 61 toward the light-receiving unit 62. The light-emitting unit 61 emits light toward the first connection channel 40. After the light is reflected by the reflection portion 65, it enters the light-receiving unit 62. Thus, the detection unit 53 detects the transmitted light.

[0072] The reflection portion 65 may include a reflection sheet 66 and a setting member 67. The reflection sheet 66 is a sheet that reflects light. The reflection sheet 66 is mounted on the setting member 67. The reflection sheet 66 is provided on the opposing surface 68 of the setting member 67. The opposing surface 68 is a surface facing the detection unit 53. That is, the reflection sheet 66 is provided on the detection unit 53 side of the setting member 67.

[0073] The reflection sheet 66 is provided at a position that is a predetermined distance from the detection unit 53. The predetermined distance only needs to be a distance determined in such a way that the light from the light-emitting unit 61 can be sufficiently reflected toward the light-receiving unit 62. The predetermined distance only needs to be a distance determined according to the type of the detection unit 53.

[0074] With the reflection portion 65, the light-emitting unit 61 and the light-receiving unit 62 may not be provided at positions facing each other across the first connection channel 40. That is, the light-emitting unit 61 and the light-receiving unit 62 may not be provided at positions sandwiching the first connection channel 40. In one example, the light-emitting unit 61 and the light-receiving unit 62 are arranged along the first connection channel 40. Thus, with the reflection portion 65, the degree of freedom related to the positions of the light-emitting unit 61 and the light-receiving unit 62 can be increased.

[0075] In the storage portion 35, a dye constituting the dye ink is dissolved in the cleaning liquid. 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.

[0076] In the method of optically detecting the dye contained in the cleaning liquid, there is a transmission method. The transmission method is a method of detecting the dye based on the amount of transmitted light through the cleaning liquid. That is, the transmission method is a method that utilizes the absorption of light by the dye.

[0077] In this way, 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 through the reflection of the reflection 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.

[0078] The detection unit 53 can detect the ink concentration of the dye ink with the liquid retained in the first connection flow path 40 as the evaluation object. That is, the detection unit 53 detects the ink concentration of the dye ink in the liquid flowing through the first connection flow path 40.

[0079] The detection unit 53 uses light with a wavelength of 400 nm or less to detect the ink concentration of the dye ink. In particular, the detection unit 53 preferably uses light with a wavelength of 340 nm to 380 nm, and most preferably uses light with a wavelength of 360 nm.

[0080] In this way, the light emitted by the light emitting unit 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 most preferably includes light with a wavelength of 360 nm.

[0081] The detection unit 53 may also include a filter. The filter is a filter that blocks light in a predetermined frequency band. If a specific example is listed, the filter may also be a filter that allows light with a wavelength of 400 nm or less to pass through and blocks light with a wavelength greater than 400 nm. The filter may also be a filter that allows light with a wavelength of 340 nm to 380 nm to pass through and blocks light with other wavelengths.

[0082] The filter may also be arranged to block light in a predetermined frequency band from the light received by the light receiving unit 62. In this case, the light receiving unit 62 may also be configured to be able to receive light with a wavelength of 400 nm or less. That is, the light receiving unit 62 may also be configured to receive at least light with a wavelength of 400 nm or less.

[0083] The filter may also be arranged to block light in a predetermined frequency band from the light emitted by the light emitting unit 61. In this case, the light emitting unit 61 may also be configured to be able to emit light with a wavelength of 400 nm or less. That is, the light emitting unit 61 may also be configured to emit at least light with a wavelength of 400 nm or less.

[0084] Properties of Dye Inks

[0085] Next, the properties of the dye inks will be described with reference to Figures 3 to 8 the following.

[0086] Figure 3 and Figure 4 are graphs showing the wavelength of light and the transmittance of the dye inks. In particular, Figure 3 and Figure 4 are graphs showing the transmittance when light is irradiated onto a liquid containing a monochromatic reactive dye ink and a cleaning liquid. As an example of the monochromatic reactive dye ink, black, gray, cyan, orange, yellow, red, and blue can be cited. Figure 3 Graphs 80 to 83 of Figure 4 are graphs with the monochromatic reactive dye inks of black, gray, cyan, and orange as evaluation objects in sequence. The liquid with an ink concentration of 0.5% of the monochromatic reactive dye ink is set as the evaluation object.

[0087] Figure 5 and Figure 6 are graphs showing the relationship between the ink concentration of the monochromatic reactive dye ink and the output level. The output level is the level represented by the amount of light received by the light receiving unit 62. As an example of the monochromatic reactive dye ink, it includes blue, gray, cyan, and orange. Figure 5 and Figure 6 Graphs 87 to 90 of Figure 5 are graphs with the monochromatic reactive dye inks of blue, gray, cyan, and orange as evaluation objects in sequence. Figure 6 is a graph showing the output level when light with a wavelength of 525 nm is irradiated.

[0088] Figure 7 is a graph showing the relationship between the transmittance of the reactive dye ink and the coefficient of determination, and the relationship between the transmittance of the reactive dye ink and the slope of the ink concentration of the reactive dye ink. The slope of the ink concentration of the reactive dye ink represents the slope of the ink concentration of the reactive dye ink and the output level. Figure 7 Graph 91 of Figure 7 is a graph showing the relationship between the transmittance of the reactive dye ink and the coefficient of determination.

[0089] Figure 8A graph showing the relationship between ink concentration and output level. Figure 8 A graph when the coefficient of determination is set to 1. Figure 8 The curve graph 93 is a curve graph with the reactive dye ink in black monochrome as the evaluation object. Figure 8 The curve graph 94 is a curve graph with the reactive dye ink in blue - green monochrome as the evaluation object.

[0090] As Figure 3 and Figure 4 shown, in the reactive dye ink, according to the color of the reactive dye ink, the light transmittance with respect to the wavelength of light is different. That is to say, in the dye ink, according to the color of the dye ink, the light absorbance with respect to the wavelength of light is different.

[0091] As Figure 5 and Figure 6 shown, in the reactive dye ink, the ink concentration and the output level of the reactive dye ink are in an inverse relationship. That is to say, the greater the ink concentration of the reactive dye ink, the smaller the output level. Thus, the greater the ink concentration of the dye ink, the smaller the amount of light received by the light - receiving part 62.

[0092] In particular, the greater the ink concentration of the reactive dye ink, the higher the linearity of the curve. When the linearity of the curve becomes higher, the error of the relationship between the ink concentration and the output level of the dye ink becomes smaller. Therefore, when the linearity of the curve becomes higher, the detection accuracy of the ink concentration of the dye ink based on the output level becomes higher.

[0093] In addition, according to the color of the reactive dye ink, the output level with respect to the ink concentration of the reactive dye ink is different. In addition, when the wavelength of the light irradiated on the liquid containing the reactive dye ink and the cleaning liquid is different, the output level with respect to the ink concentration of the reactive dye ink is different.

[0094] As Figure 7 shown, in order to improve the detection accuracy of the ink concentration, meeting both the first criterion and the second criterion will be appropriate conditions. The first criterion is a criterion such that the coefficient of determination is 0.8 or more. The second criterion is a criterion such that the slope of the ink concentration is 80 or more. The second criterion is equivalent to the slope of the ink concentration at which the output level decreases by 40% when the ink concentration is 0.5%. In such a case, it is an appropriate condition that the light transmittance of the ink is 8% to 50%. That is to say, as the light transmittance ratio of the ink, 0.08 to 0.5 is an appropriate condition.

[0095] As Figure 3 and Figure 4As shown, there is a tendency that, as the light transmittance of the ink, when the light has a wavelength of 340 nm or more and 380 nm or less, the deviation is less in the inks of each color. Therefore, the light emitted from the light emitting unit 61 most preferably includes light having a wavelength of 340 nm or more and 380 nm or less. In addition, the light emitted from the light emitting unit 61 only needs to include ultraviolet light such as light having a wavelength of 400 nm or less. The light emitted from the light emitting unit 61 may also include visible purple light such as light having a wavelength of 380 nm or more and 430 nm or less.

[0096] As Figure 8 shown, when light having a wavelength of 360 nm is used, the linearity of the curves in the graphs 93 and 94 becomes higher. The graph 93 is a black monochromatic reactive dye ink as an example where there is a tendency for the transmittance to be small. The graph 94 is a blue-green monochromatic reactive dye ink as an example where there is a tendency for the transmittance to be small. Thus, in the dye inks of each color, the linearity of the graph becomes higher.

[0097] Accordingly, the detection unit 53 uses light having a wavelength of 400 nm or less to detect the amount of light received by the light receiving unit 62. Thereby, the ink concentration of the dye ink can be detected. In particular, the detection unit 53 most preferably uses light having a wavelength of 360 nm, and preferably uses light in the range of 340 nm to 380 nm with a center wavelength of 360 nm.

[0098] The control implemented by the cleaning control unit 54

[0099] The cleaning control unit 54 determines whether to discharge the cleaning liquid by comparing the detection result of the detection unit 53 with a threshold value. When the ink concentration of the dye ink is equal to or higher than the threshold value, the cleaning control unit 54 discharges the cleaning liquid from the storage unit 35. At this time, the cleaning control unit 54 discharges the cleaning liquid from the storage unit 35 by opening the first on-off valve 44 and the third on-off valve 51. After the discharge of the cleaning liquid is completed, 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. Thereby, the cleaning liquid can be replaced.

[0100] When the cleaning control unit 54 is to discharge the cleaning liquid, it can also determine whether the recording device 11 is in the recording state. The cleaning control unit 54 can also determine whether the recording device 11 is in the recording state by communicating with the recording control unit 15. The cleaning control unit 54 can also determine whether the recording device 11 is in the recording state by receiving an operation from the user. When the recording device 11 is in the recording state, it is preferable that the cleaning liquid is stored in the cleaning tank 36. Therefore, when the recording device 11 is in the recording state, the cleaning control unit 54 opens the second on-off valve 49 while closing the first on-off valve 44, thereby discharging the cleaning liquid from the storage tank 39. Thus, while the cleaning liquid can be held in the cleaning tank 36, the cleaning liquid can be replaced in the storage tank 39.

[0101] Functions and effects of the first embodiment

[0102] The functions and effects of the first embodiment will be described.

[0103] (1) Based on the detection result obtained by the detection unit 53, the cleaning control unit 54 controls to discharge the cleaning liquid from the storage unit 35. The light emitted by the light emitting unit 61 includes light with a wavelength of 400 nm or less. According to this structure, even for dye inks, it is possible to use light with a wavelength that satisfies appropriate conditions to improve the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be discharged appropriately.

[0104] (2) The wavelength of the light emitted by the light emitting unit 61 includes light with a wavelength of 340 nm or more and 380 nm or less. According to this structure, even for dye inks, light with a wavelength that satisfies the most preferable conditions will be used, so that the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid can be further improved. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be discharged appropriately.

[0105] (3) The cleaning device 31 may also include a reflection unit 65 provided on the opposing surface 68 that opposes the installation surface 64 where the light emitting unit 61 and the light receiving unit 62 are installed. According to this structure, the arrangement of the light emitting unit 61 and the light receiving unit 62 can be adjusted by the reflection unit 65. Thus, even for dye inks, the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid can be further improved. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be discharged appropriately.

[0106] (4) Further, even if the light-emitting unit 61 and the light-receiving unit 62 are not opposed to each other, the light-receiving unit 62 can receive the light from the light-emitting unit 61. Thus, the light-emitting unit 61 and the light-receiving unit 62 can be collectively arranged. Therefore, miniaturization of the cleaning device 31 can be achieved.

[0107] (5) The storage unit 35 includes a cleaning tank 36, a storage tank 39, and a first connecting 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 connecting flow path 40 is provided so as to connect the cleaning tank 36 and the storage tank 39. The detection unit 53 is provided on the first connecting flow path 40. According to this structure, in the first connecting flow path 40 which tends to have a smaller diameter compared with the cleaning tank 36 and the storage tank 39, the ink concentration of the dye ink can be detected. Thus, even for the dye ink, the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid can be further improved. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0108] (6) The cleaning device 31 includes a pump 45 that circulates the cleaning liquid through the first connecting flow path 40 and the second connecting flow path 41 between the cleaning tank 36 and the storage tank 39. According to this structure, by circulating the cleaning liquid between the cleaning tank 36 and the storage tank 39, it becomes easier to make the ink concentration of the dye ink contained in the cleaning liquid uniform. Thus, even for the dye ink, the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid can be further improved. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0109] Modification example

[0110] This embodiment can be modified and implemented as follows. This embodiment and the following modification examples can be implemented in combination with each other within a technically non-contradictory range.

[0111] · The detection unit 53 only needs to be provided in the storage unit 35. The detection unit 53 can also be provided on the storage tank 39. The detection unit 53 can also be provided on the cleaning tank 36. In this case, the ink concentration of the dye ink in the cleaning tank 36 in which the cleaning unit 32 is immersed in the cleaning liquid can be detected. Thus, even for the dye ink, the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid can be further improved. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0112] · When the detection unit 53 is provided on the cleaning tank 36, the cleaning device 31 may not have the storage tank 39. In this case, the cleaning device 31 may be configured such that the discharge flow path 50 is directly connected to the cleaning tank 36. Thus, the cleaning device 31 can be configured with a minimum of functions for the storage unit 35. Therefore, miniaturization and cost reduction of the cleaning device 31 can be achieved.

[0113] · The reflecting unit 65 may not be configured to mount the reflecting sheet 66 on the setting member 67 as long as it can reflect the light from the light emitting unit 61 toward the light receiving unit 62. The reflecting unit 65 may be configured such that the reflecting sheet 66 and the setting member 67 are integrally formed as long as it can reflect the light from the light emitting unit 61 toward the light receiving unit 62.

[0114] · In the region where the detection unit 53 is provided, the diameter of the first connection flow path 40 may be reduced. The light emitting unit 61 and the light receiving unit 62 may be provided at positions sandwiching the first connection flow path 40. In this case, the cleaning device 31 may not have the reflecting unit 65.

[0115] · As an object of the applied invention, not only the cleaning device 31 but also the recording device 11 having the functions of the cleaning device 31 may be used. In addition, the recording device 11 may have a part of the functions of the cleaning device 31 or may have all of the functions of the cleaning device 31.

[0116] · The expression "at least any one" used in this specification means one or more of the desired options. As an example, if the number of options is two, the expression "at least any one" used in this specification means only one option or both of the two options. As another example, if the number of options is three or more, the expression "at least any one" used in this specification means only one option or any combination of two or more of the options.

[0117] Supplementary Note

[0118] Hereinafter, the technical idea and its effects grasped from the above-described embodiments and modification examples will be described. The technical idea and its effects of the present technology can be combined with each other within a technically non-contradictory range.

[0119] (A) The cleaning device includes: a storage unit that stores the cleaning liquid for the cleaning conveyor belt, and the conveyor belt conveys the medium; an optical sensor that detects the ink concentration of the dye ink mixed in the cleaning liquid stored in the storage unit; a control unit that controls the discharge of the cleaning liquid from the storage unit. The optical sensor has 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 discharge of the cleaning liquid from the storage unit based on the detection result obtained by the optical sensor. The light emitted from the light-emitting unit includes light with a wavelength of 400 nm or less.

[0120] According to this structure, even for dye ink, light with a wavelength that meets appropriate conditions is used, so that the detection accuracy of the ink concentration of the dye ink mixed in the cleaning liquid can be improved. Therefore, by accurately detecting the ink concentration mixed in the cleaning liquid, the cleaning liquid can be discharged appropriately.

[0121] (B) It can also be set that, in the above cleaning device, the wavelength of the light emitted from the light-emitting unit includes light with a wavelength of 340 nm or more and 380 nm or less.

[0122] According to this structure, even for dye ink, light with a wavelength that meets the most preferred conditions is used, so that the detection accuracy of the ink concentration of the dye ink mixed in the cleaning liquid can be further improved. Therefore, by accurately detecting the ink concentration mixed in the cleaning liquid, the cleaning liquid can be discharged appropriately.

[0123] (C) It can also be set that the above cleaning device includes a reflection unit, and the reflection unit is provided on the opposing surface that is opposed to the installation surface where the light-emitting unit and the light-receiving unit are installed.

[0124] According to this structure, the configuration of the light-emitting unit and the light-receiving unit can be adjusted by the reflection unit. Thus, even for dye ink, the detection accuracy of the ink concentration of the dye ink mixed in the cleaning liquid can be further improved. Therefore, by accurately detecting the ink concentration mixed in the cleaning liquid, the cleaning liquid can be discharged appropriately.

[0125] In addition, even if the light-emitting unit and the light-receiving unit are not opposed to each other, the light-receiving unit can receive the light from the light-emitting unit. Thus, the light-emitting unit and the light-receiving unit can be configured in a centralized manner. Therefore, miniaturization of the cleaning device can be achieved.

[0126] (D) It can also be set that the above cleaning device is provided with a cleaning part, and the cleaning part cleans the conveyor belt with a cleaning liquid. The storage part includes a cleaning tank, a storage tank, and a connecting flow path. The cleaning tank is a tank in which the cleaning part is immersed in the stored cleaning liquid. The connecting flow path is provided in a manner of connecting the cleaning tank and the storage tank, and the optical sensor is provided on the connecting flow path.

[0127] According to this structure, it is possible to detect the ink concentration of the dye ink in the connecting flow path that tends to have a smaller diameter compared to the cleaning tank and the storage tank. Thus, even for dye ink, it is possible to further improve the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0128] (E) It can also be set that the above cleaning device is provided with a cleaning part, and the cleaning part cleans the conveyor belt with a cleaning liquid. The storage part includes a cleaning tank, and the cleaning tank stores the cleaning liquid. The cleaning tank is a tank in which the cleaning part is immersed in the stored cleaning liquid, and the optical sensor is provided on the cleaning tank.

[0129] According to this structure, it is possible to provide an optical sensor on the cleaning tank in which the cleaning part is immersed in the cleaning liquid. Thus, even for dye ink, it is possible to further improve the detection accuracy of the ink concentration of the dye ink mixed into the cleaning liquid. Therefore, by accurately detecting the ink concentration mixed into the cleaning liquid, the cleaning liquid can be appropriately discharged.

[0130] (F) The recording device includes: the above cleaning device; a conveying part having the conveyor belt; and a recording part that performs recording by ejecting dye ink onto a medium conveyed by the conveying part. According to this structure, the same effect as that of (A) can be achieved.

[0131] Symbol Explanation

[0132] A1…Transport direction; A2…Opposite direction; 11…Recording device; 12…Recording unit; 13…Nozzle; 14…Nozzle surface; 15…Recording control unit; 21…Transport unit; 22…First transport roller; 23…Second transport roller; 24…Drive source; 25…Conveyor belt; 26…Inner circumferential surface; 27…Outer circumferential surface; 28…Pressing part; 31…Cleaning device; 32…Cleaning unit; 33…Cleaning roller; 34…Cleaning blade; 35…Retention part; 36…Cleaning tank; 37…Immersion tank; 38…Supporting tank; 39…Storage tank; 40…First connecting flow path; 41…Second connecting flow path; 42…Cleaning filter; 43…Storage filter; 44…First on-off valve; 45…Pump; 46…Flowmeter; 47…Constant flow valve; 48…Supply flow path; 49…Second on-off valve; 50…Discharge flow path; 51…Third on-off valve; 52…Liquid amount sensor; 53…Detection unit; 54…Cleaning control unit; 61…Light emitting part; 62…Light receiving part; 63…Substrate; 64…Setting surface; 65…Reflection part; 66…Reflection sheet; 67…Setting member; 68…Opposing surface; 80 to 93…Graphs; 99…Medium.

Claims

1. A cleaning device, characterized in that: have: A storage unit for storing a cleaning liquid for cleaning a conveyor belt, wherein the conveyor belt transports the medium; an optical sensor for detecting the ink concentration of the dye ink mixed into the cleaning liquid stored in the storage portion; a control unit configured to control the cleaning liquid to be discharged from the storage unit, 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 performs control based on the detection result obtained by the optical sensor so as to discharge the cleaning liquid from the storage unit. The light emitted by the light emitting unit includes light having a wavelength of 400 nm or less.

2. The cleaning device according to claim 1, characterized in that: The wavelength of light emitted by the light emitting unit includes light with a wavelength of 340 nm to 380 nm.

3. The cleaning device according to claim 1, characterized in that: A reflecting portion is provided, and the reflecting portion is provided on a surface facing a surface on which the light emitting portion and the light receiving portion are provided.

4. The cleaning device according to claim 1, characterized in that: A cleaning unit is provided, wherein the cleaning unit cleans the conveyor belt with a cleaning liquid. The storage portion includes a cleaning tank, a storage tank, and a connecting flow channel. The cleaning tank is a tank in which the cleaning part is immersed in the stored cleaning liquid. The connecting channel is provided in a manner to connect the cleaning tank and the storage tank. The optical sensor is disposed on the connecting flow channel.

5. The cleaning device according to claim 1, characterized in that: A cleaning unit is provided, wherein the cleaning unit cleans the conveyor belt with a cleaning liquid. The storage unit includes a cleaning tank, and the cleaning tank stores the cleaning liquid. The cleaning tank is a tank in which the cleaning part is immersed in the stored cleaning liquid. The optical sensor is disposed on the cleaning tank.

6. A recording device, characterized in that: have: The cleaning device according to any one of claims 1 to 5; a conveying portion, which has the conveying belt; The recording unit performs recording by ejecting dye ink onto the medium transported by the transport unit.

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