Printing apparatus, control method therefor, and storage medium

Abstract

To provide a recording device capable of appropriately cleaning a cap with a cleaning liquid.SOLUTION: The inkjet recording apparatus includes a cap for capping a recording head for ejecting liquid, a discharge part for discharging the liquid from the recording head to the cap, a supply part for supplying cleaning liquid for cleaning the liquid in the cap to the cap, and a control part for controlling the supply amount of the cleaning liquid to the cap by the supply part according to the discharge amount of the liquid from the recording head to the cap.SELECTED DRAWING: Figure 14

Description

[Technical Field]

[0001] The present invention relates to a recording device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there is known a liquid ejection device that includes a waste liquid flow path that serves as a flow path for ink sucked from a nozzle, and that cleans the cap by supplying cleaning liquid to the cap through the waste liquid flow path.

[0003] Patent Document 1 discloses a device that controls a cleaning unit so that the amount of cleaning liquid supplied varies depending on the time that has elapsed since the ink suction operation was performed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-130812 Summary of the Invention [Problem to be solved by the invention]

[0005] However, conventional recording devices have the following problems.

[0006] When ink is sucked from the nozzles by applying negative pressure to the cap, the amount of ink sucked from the nozzles varies depending on the negative pressure reached during suction, the suction time, and other factors.

[0007] The amount of cleaning fluid required to clean the cap varies depending on the amount of ink discharged into the cap, so if the cap cleaning operation is performed under the same conditions, a small amount of cleaning fluid will lead to ink solidification in the waste fluid flow path, while a large amount of cleaning fluid will lead to excessive consumption of cleaning fluid.

[0008] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a recording device that can properly clean a cap with a cleaning liquid. [Means for solving the problem]

[0009] The recording device according to the present invention is characterized by comprising a cap for capping a recording head that ejects liquid, a discharge means for discharging liquid from the recording head into the cap, a supply means for supplying cleaning liquid to the cap for cleaning the liquid in the cap, and a control means for controlling the amount of cleaning liquid supplied to the cap by the supply means in accordance with the amount of liquid discharged from the recording head to the cap. [Effects of the Invention]

[0010] According to the present invention, it is possible to properly clean the cap with the cleaning liquid. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of an inkjet recording apparatus according to a first embodiment. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. [Figure 5] FIG. 4 is a diagram showing the configuration of a flow path to a maintenance unit. [Figure 6] FIG. 4 is a perspective view showing the arrangement of a cleaning liquid and negative pressure supply unit. [Figure 7] FIG. 2 is a perspective view showing the configuration of a cleaning liquid and negative pressure supply unit. [Figure 8] FIG. 2 is a perspective view showing the cleaning liquid and negative pressure supply unit and the surrounding configuration. [Figure 9] FIG. 4 is a perspective view showing a cleaning liquid supply channel of the cap tray. [Figure 10] FIG. 10 is a perspective view of a three-way valve upstream of the cap in the cleaning liquid supply channel. [Figure 11] FIG. 10 is a front view showing the arrangement of the cap upstream three-way valve. [Figure 12] 10 is a flowchart showing a suction operation when goods arrive. [Figure 13] 10 is a flowchart showing a suction operation during maintenance. [Figure 14] 10 is a flowchart showing the operation of cleaning a cap. [Figure 15] 10 is a flowchart showing an operation of counting accumulated preliminary ejection. [Figure 16] 10 is a flowchart showing the operation of counting the evaporation rate in the cap. [Figure 17] Parameter table of count values ​​for evaporation rate inside the cap. [Figure 18] 10 is a flowchart showing the operation of determining whether to clean a cap. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0013] (First embodiment) First, as a definition of directions, the top of the device in FIG. 1 is defined as the upward direction (+z direction), right to left as the longitudinal direction (-x direction), and the direction from the front to the back of the page perpendicular to the sheet transport direction as the sheet width direction (+y direction). The front side of the page is the front side of the device, and the back side of the page is the rear side of the device. Note that in the following embodiments, a specific configuration of the recording head and recording device will be described, but the present invention is not limited to this. For example, the present invention is not limited to line head printers, but can also be applied to serial head printers. Furthermore, the present invention is not limited to sheet-fed recording devices, but can also be applied to reel-type recording devices.

[0014] 1 is a schematic diagram showing the general configuration of an inkjet recording apparatus 1 (hereinafter also referred to as recording apparatus 1) according to this embodiment. This inkjet recording apparatus 1 is a sheet-fed inkjet recording apparatus that produces a recorded matter by forming an ink image on a sheet S using two liquids, a reaction liquid and ink.

[0015] The inkjet recording apparatus 1 of this embodiment includes a paper feed module 1000, a print module 2000, a drying module 3000, a fixing module 4000, a cooling module 5000, a reversing module 6000, and a discharge stacking module 7000.

[0016] A cut sheet S supplied from the paper feed module 1000 is conveyed along a conveyance path, processed in each module, and discharged to the discharge stacking module 7000.

[0017] The paper feed module 1000 is provided with three storage cabinets 1100a to 1100c for storing sheets S, and the storage cabinets 1100a to 1100c are configured to be able to be pulled out toward the front of the device. The sheets S are fed one by one in each storage cabinet 1100a to 1100c by a separation belt and a transport roller, and are transported to the print module 2000. The number of storage cabinets 1100a to 1100c is not limited to three, and the configuration may include one, two, four or more.

[0018] The print module 2000 has a pre-imaging registration correction unit (not shown), a print belt unit 2200, and a recording unit 2300. The pre-imaging registration correction unit corrects the tilt and position of the sheet S transported from the paper feed module 1000, and the sheet is then transported to the print belt unit 2200. The recording unit 2300 is disposed on the transport path at a position opposite the print belt unit 2200. The recording unit 2300 is a sheet processing unit that performs recording processing (printing) on ​​the transported sheet S from above using a recording head 22 (see FIG. 2) to form an image.

[0019] The sheet S is attracted and transported by the print belt unit 2200, ensuring clearance with the recording heads. A plurality of recording heads 22 are arranged in a line along the transport direction. In this example, there are a total of five line-type recording heads corresponding to four colors, Y (yellow), M (magenta), C (cyan), and Bk (black), as well as P (reaction liquid). Note that the number of colors and the number of recording heads 22 are not limited to five.

[0020] The inkjet method can employ a method using a heating element, a method using a piezoelectric element, a method using an electrostatic element, a method using a MEMS element, or the like. Ink of each color is supplied to the recording head 22 from an ink tank (not shown) via an ink tube. The sheet S printed by the recording unit 2300 is transported by the print belt unit 2200. An in-line scanner (not shown) arranged downstream in the transport direction of the recording unit 2300 can detect misalignment and color density of the image formed on the sheet S and correct the printed image.

[0021] The drying module 3000 has a decoupling section 3200, a drying belt unit 3300, and a hot air blowing section 3400, and is a unit that reduces the liquid content contained in the ink applied onto the sheet S by the recording section 2300 and improves the fixation of the ink to the sheet S. The sheet S printed by the recording section 2300 of the print module 2000 is transported to the decoupling section 3200 arranged within the drying module 3000.

[0022] In the decoupling section 3200, the sheet S is transported by air pressure from above and friction of the belt. By loosely holding and transporting the sheet S on the belt, the sheet S on the print belt unit 2200, where the ink image is formed, is prevented from shifting.

[0023] The sheet S conveyed from the decoupling section 3200 is attracted and conveyed by the drying belt unit 3300, and at the same time, hot air is blown from the hot air blowing section 3400 arranged above the belt to dry the ink-applied surface of the sheet S. As a drying method, in addition to the method of blowing hot air, a method of irradiating the surface of the sheet S with electromagnetic waves (ultraviolet rays, infrared rays, etc.) or a conductive heat transfer method by contact with a heating element can be used in combination.

[0024] The fixing module 4000 has a fixing belt unit 4100, and fixes the ink onto the sheet S by passing the sheet S conveyed from the drying module 3000 between a heated upper belt unit and a heated lower belt unit.

[0025] The cooling module 5000 has multiple cooling units 5100, which cool the high-temperature sheet S transported from the fixing module 4000. The cooling units 5100 use a fan to draw outside air into a cooling box, increase the pressure inside the cooling box, and then spray the air from nozzles formed in the transport guide. The sheet S can be cooled by blowing this sprayed air onto it. The cooling units 5100 are arranged on both sides of the transport path, and can cool the sheet S from both sides.

[0026] A transport path switching unit is also provided within the cooling module 5000. The transport path switching unit can switch the transport path of the sheet S depending on whether the sheet S is transported to the inversion module 6000 or to a duplex transport path used for duplex printing. During duplex printing, the sheet S is transported to a transport path below the cooling module 5000 and further transported along a duplex transport path through the fixing module 4000, drying module 3000, print module 2000, and paper feed module 1000. The sheet S is then transported again to the pre-image registration correction unit of the print module 2000, the print belt unit 2200, and the recording unit 2300, where it is printed. A first inversion unit 4200 that inverts the sheet S is provided in the duplex transport section of the fixing module 4000.

[0027] The reversing module 6000 has a second reversing unit 6400 and can reverse the front and back of the conveyed sheet S. This allows the front and back orientation of the discharged sheet S to be freely changed.

[0028] The discharge stacking module 7000 has a top tray 7200 and a stacking section 7500, and aligns and stacks the sheets S conveyed from the reversing module 6000.

[0029] The maintenance unit 17 is a unit equipped with a mechanism for restoring the ejection performance of the recording head 22. Examples of such mechanisms include a capping mechanism that provides capping to protect the ink ejection surface of the recording head 22, a wiper mechanism that wipes the ink ejection surface, and a suction mechanism that negatively pressure-sucks ink from the recording head 22 through the ink ejection surface. The maintenance unit 17 is also equipped with a drive mechanism and rails (not shown), and is capable of reciprocating horizontally along the rails. The maintenance unit 17 moves to a position directly below the recording head 22 when maintenance is performed on the recording head 22, and moves to a position away from directly below the recording head when maintenance is not performed.

[0030] (Recording head configuration) 2 is a perspective view of the recording head 22. As shown in Fig. 2, the recording head 22 has a nozzle plate 223 with a plurality of nozzles that eject ink aligned in the longitudinal direction of the recording head 22 (the sheet width direction, the y direction). In addition, positioning portions 221 are provided on both ends of the recording head 22. Specifically, a first contact portion 221a consisting of a recess with a conical slope is provided on the front side of the head in the longitudinal direction, a second contact portion 221b consisting of a groove with two V-shaped flat surfaces is provided on the back side of the head in the longitudinal direction, and a third contact portion 221c consisting of a flat surface are provided.

[0031] (Maintenance Department Configuration) Next, the configuration of the maintenance unit 17 of the recording device 1 will be described with reference to FIGS.

[0032] In this embodiment, the maintenance unit 17 is divided into a cap tray 18 on which a cap mechanism 181 (see FIG. 3) is arranged, and a cleaning tray 19 on which a cleaning mechanism 191 (see FIG. 4) is arranged. The cap tray 18 and the cleaning tray 19 are configured to be movable in the longitudinal direction of the device (x direction) by a drive motor (not shown) and rails provided on the housing.

[0033] 3, each cap mechanism 181 in the cap tray 18 has a plurality of spherical head positioning members 182 facing the recording head 22 in order to position the recording head 22. The head positioning members 182 are arranged at the front and rear of the cap mechanism 181 in the sheet width direction (y direction). Three head positioning members 182 are required to position one recording head 22 relative to the cap mechanism 181, with one arranged at the front side and two arranged at the back side of the cap mechanism 181.

[0034] The recording head 22 and the cap mechanism 181 are positioned by positioning portions 221 provided on both ends of the recording head 22 coming into contact with head positioning members 182 of the cap mechanism 181. By being positioned with the recording head 22, the cap mechanism 181 can protect a nozzle plate 223 of the recording head 22 and perform negative pressure suction using a negative pressure suction mechanism described later.

[0035] 4, the cleaning tray 19 is provided with a plurality of spherical head positioning members 192 facing the recording heads 22 in order to position the plurality of recording heads 22. The head positioning members 192 are arranged at the front and rear of the sheet width direction (y direction) inside the cleaning tray 19, respectively, and are held by beam members 193a and 193b arranged across the sheet conveyance direction. Three head positioning members 192 are required to position one recording head 22 relative to the cleaning tray 19; one is arranged on the front beam member 193a inside the cleaning tray 19, and two are arranged on the rear beam members 193b. The recording heads 22 and cleaning tray 19 are positioned when positioning portions 221 provided on both ends of the recording heads 22 abut against the head positioning members 192 of the cleaning tray 19.

[0036] The positioning configuration is not limited to a configuration using a spherical positioning member, and other configurations may be used, such as a configuration in which a part of the recording head 22 is pressed against the inside of the cleaning tray 19, or a configuration in which positioning is performed using holes and pins provided in the cleaning tray 19 and the recording head 22.

[0037] The cleaning mechanism 191 has a cleaning liquid application unit 50 that applies cleaning liquid to the nozzle plate 223 of the recording head 22, and a liquid removal unit 60 that removes ink, paper dust, and cleaning liquid adhering to the recording head 22. It also has a negative pressure application unit 70 that applies negative pressure to the nozzle plate 223 of the recording head 22 to remove ink that has solidified in the nozzle portion and remove bubbles in the ink flow path.

[0038] 4, the cleaning tray 19 has a moving mechanism (not shown) that moves the cleaning mechanism 191 along a wiping direction D that is perpendicular to the sheet conveying direction. The cleaning mechanism 191 removes ink and dust from the nozzle surface of the recording head 22 by combining a cleaning liquid applying unit 50, a liquid removing unit 60, and a negative pressure applying unit 70.

[0039] (Flow path configuration) Next, the cleaning liquid supply channel, the negative pressure suction channel, and the waste liquid channel will be described with reference to FIG.

[0040] The cleaning liquid is sent from a cleaning liquid pack 101 to a cleaning liquid sub-tank 103 by a pump 102. Furthermore, the cleaning liquid can be sent from the cleaning liquid sub-tank 103 to the capping mechanism 181, the cleaning liquid deposition unit 50, and the negative pressure application unit 70 by a cleaning liquid supply pump 104 provided in a cleaning liquid and negative pressure supply unit 500 (Y, M, C, Bk, P) corresponding to each head. Furthermore, the timing of supplying the cleaning liquid to the capping mechanism 181, the cleaning liquid deposition unit 50, and the negative pressure application unit 70 can be controlled by each of the opening and closing valves 105 to 107.

[0041] Negative pressure is applied to the capping mechanism 181 and the negative pressure applying unit 70 by a suction pump 206 connected to a negative pressure tank 205. Negative pressure can be applied to the capping mechanism 181 and the negative pressure applying unit 70 from the negative pressure tank 205 through each of the on-off valves 207 to 209.

[0042] When negative pressure is applied by the cap mechanism 181 and the negative pressure applying unit 70, waste liquid is sucked from the recording head 22 from the negative pressure tank 205 to the drain sub-tank 203 by the pump 204, and is further stored in the waste liquid tank 201 by the pump 202.

[0043] A recovery tray 300 is provided for recovering the cleaning liquid overflowing from the cleaning liquid deposition unit 50 , and the overflowing cleaning liquid is sent to a drain sub-tank 203 by a pump 210 .

[0044] When the capacity of the waste liquid tank 201 approaches its upper limit, this is detected by a waste liquid tank detection sensor (not shown), and the user is prompted to replace the waste liquid tank 201.

[0045] The waste liquid from the head of the reaction liquid (P) is collected in a drain sub-tank 303 for the reaction liquid by a pump 304, separate from the waste liquid flow paths from the color ink heads (Y to Bk), and is further stored in a waste liquid tank 301 for the reaction liquid by a pump 302. Therefore, the reaction liquid (P) and the color inks (Y to Bk) do not mix in the waste liquid flow path, and it is possible to prevent the inks from solidifying in the flow path and clogging the flow path.

[0046] As explained above, the cleaning liquid and negative pressure supply unit 500 (Y, M, C, Bk, P) corresponding to each head is provided with a cleaning liquid supply pump 104 and on-off valves 105-107 for controlling the supply of cleaning liquid to each flow path. Furthermore, a negative pressure tank 205, a suction pump 206 for negative pressure suction, and on-off valves 207-209 for controlling the application of negative pressure to each part are also provided. In this way, in this embodiment, the electrical devices and on-off valves required for each cleaning liquid and negative pressure supply unit 500 (Y, M, C, Bk, P) corresponding to each head are unitized.

[0047] The inkjet recording apparatus 1 includes a CPU (Central Control Unit) 150, and each block shown in Fig. 5 is controlled by the CPU 150 executing a control program stored in a memory 151. The operations of the flowcharts shown below are realized by the CPU 150 executing the control program stored in the memory 151.

[0048] Next, the configuration of the cleaning liquid and negative pressure supply unit in this embodiment will be described with reference to FIGS.

[0049] Fig. 6 is a view of the print module 2000 of Fig. 1 as seen from the rear side of the apparatus. As shown in Fig. 6, a cleaning liquid and negative pressure supply unit 500 (Y, M, C, Bk, P) is disposed below the rear side of the print module 2000. In addition, a cleaning liquid sub-tank 103 and pump 102, a drain sub-tank 203 and pumps 202, 204, 210, and a reaction liquid drain sub-tank 303 and pumps 302, 304, 310 are disposed side by side in the longitudinal direction (x direction).

[0050] Between the cleaning liquid and negative pressure supply units 500P (for reaction liquid) and 500Y (for yellow ink), a space 500X is provided in which an additional cleaning liquid and negative pressure supply unit can be placed when the number of colors or the number of recording heads 22 is greater than in this embodiment. Also, below these cleaning liquid and negative pressure supply units 500 (Y, M, C, Bk, P), a space is provided in which a double-sided conveying path 2500 (FIG. 1) is placed, along which the sheet S is conveyed during double-sided printing.

[0051] 7 is a perspective view showing the arrangement of the negative pressure tank 205 and various pumps arranged inside the cleaning liquid and negative pressure supply unit 500. As shown in Fig. 7, in each cleaning liquid and negative pressure supply unit 500, the negative pressure tank 205 is arranged below the unit, and the cleaning liquid supply pump 104, the negative pressure suction pump 206, and the on-off valves 105-107, 207-209 are arranged above the negative pressure tank 205. Therefore, even if a liquid leak occurs from the negative pressure tank 205 that stores ink or reaction liquid, it is possible to reduce the risk of ink or reaction liquid getting on electrical components such as the cleaning liquid supply pump 104 and the negative pressure suction pump 206, which are electrical components, and causing them to break down.

[0052] FIG. 8 is a diagram showing a state in which the cleaning liquid and negative pressure supply unit 500Y is disposed inside the apparatus main body, and the adjacent cleaning liquid and negative pressure supply units 500M and 500C are removed.

[0053] A liquid tube 520 connected to the cleaning liquid and negative pressure supply unit 500Y runs from a side surface (521) of the cleaning liquid and negative pressure supply unit 500Y through a rear surface (522) thereof to a connection destination. Furthermore, an electric cable 530 for connecting to the electric components of the cleaning liquid and negative pressure supply unit 500Y is connected to the apparatus body via electric connectors 532 and 533 on the upper surface (531) of the cleaning liquid and negative pressure supply unit 500Y.

[0054] When removing the cleaning liquid and negative pressure supply unit 500Y from the apparatus body, the tube joints 523 and 524 are removed from the side surface (521) of the cleaning liquid and negative pressure supply unit 500Y. Also, the electrical connectors 532 and 533 are removed from the top surface (531) of the cleaning liquid and negative pressure supply unit 500Y. This easily releases the ink liquid and electrical connections between the cleaning liquid and negative pressure supply unit 500Y and the apparatus body.

[0055] Furthermore, the screws 600 that secure the cleaning liquid and negative pressure supply unit 500Y to the apparatus body are removed from the front side of the cleaning liquid and negative pressure supply unit 500Y. Then, the cleaning liquid and negative pressure supply unit 500Y can be removed from the apparatus body by pulling out the attachment / detachment handle 610 in the direction of arrow E.

[0056] In this case, the liquid tubes 520 and the electric cables 530 connected to the cleaning liquid and negative pressure supply unit 500Y are arranged on the rear surface (522) and top surface (531) of the unit, which do not hinder removal in the direction of removal (arrow E) of the cleaning liquid and negative pressure supply unit 500. Therefore, the cleaning liquid and negative pressure supply unit 500 can be easily removed without being hindered from being removed. Note that a liquid leakage prevention tray 510 is arranged below the cleaning liquid and negative pressure supply unit 500, and a leakage detection sensor (not shown) is arranged in the liquid leakage prevention tray 510.

[0057] Even if a liquid leak occurs from the negative pressure tank 205 that stores ink or reaction liquid, the leaked ink or reaction liquid is collected in the liquid leakage prevention tray 510 because the liquid leakage prevention tray 510 is provided to cover the entire underside of the cleaning liquid and negative pressure supply unit 500. Furthermore, since the liquid in the liquid leakage prevention tray 510 can be detected by a leakage detection sensor (not shown), appropriate measures can be taken, such as immediately stopping the device, if liquid is detected. This makes it possible to prevent ink or reaction liquid from leaking into the duplex conveying path 2500, which is located below the placement section of the cleaning liquid and negative pressure supply unit 500.

[0058] The paths of the liquid tube 520 and the electric wires 530 are not limited to the rear surface and the top surface of the cleaning liquid and negative pressure supply unit 500, but may also be arranged on the rear surface, top surface, bottom surface, etc. This allows the cleaning liquid and negative pressure supply unit 500 to be easily removed without being hindered from being removed, as described above.

[0059] As described above, in the recording apparatus 1 of this embodiment, the cleaning liquid and negative pressure supply unit 500 includes, as a unit, the cleaning liquid supply pump 104 corresponding to the cleaning configuration of each head, the on-off valves 105 to 107 for controlling the supply of cleaning liquid to each flow path, the negative pressure tank 205, the suction pump 206 for negative pressure suction, and the on-off valves 207 to 209 for controlling the application of negative pressure to each part. Therefore, the parts corresponding to the cleaning configuration of each head can be easily removed for replacement or maintenance work.

[0060] Furthermore, the liquid tubes 520 and the electric cables 530 connected to the cleaning liquid and negative pressure supply unit 500 are arranged on the rear, upper and lower surfaces of the unit in the removal direction (arrow E) of the cleaning liquid and negative pressure supply unit 500, where they do not hinder removal. Therefore, the cleaning liquid and negative pressure supply unit 500 can be easily removed without hindering removal.

[0061] (Configuration of three-way valve in cleaning liquid supply flow path) Next, the configuration of the three-way valve of the cleaning liquid supply flow path that supplies the cleaning liquid to the capping mechanism 181 in this embodiment will be described with reference to FIGS.

[0062] 9 is a perspective view of the cleaning liquid supply flow path 183 in the cap tray 18. As shown in Fig. 9, the cleaning liquid supply flow path 183 of the cap mechanism 181 corresponding to each recording head 22 is equipped with a plurality of cap upstream three-way valves 184, and has a three-way valve upstream flow path 183a and a three-way valve downstream flow path 183b. The plurality of cap upstream three-way valves 184 are supported by a three-way valve support member 185 by a fixing method (not shown).

[0063] 10 is a perspective view of the cap upstream three-way valve 184. As shown in FIG. 10, the cap upstream three-way valve 184 has a three-way valve inlet 184a, a three-way valve supply outlet 184b, and a three-way valve atmosphere-communication port 184c. The three-way valve inlet 184a is connected to a three-way valve upstream flow path 183a, and the three-way valve supply outlet 184b is connected to a three-way valve downstream flow path 183b. The cap upstream three-way valve 184 is switchable between an atmosphere-disconnected state in which the three-way valve inlet 184a and the three-way valve supply outlet 184b are connected and the three-way valve atmosphere-communication port 184c is closed, and an atmosphere-communication state in which the three-way valve inlet 184a is closed and the three-way valve supply outlet 184b and the three-way valve atmosphere-communication port 184c are connected.

[0064] In the atmosphere non-communication state, the three-way valve upstream flow path 183a and the three-way valve downstream flow path 183b are connected, so that the cleaning liquid can be supplied from the cleaning liquid supply pump 104 to the capping mechanism 181. In the atmosphere-communication state, the three-way valve downstream flow path 183b and the three-way valve atmosphere communication port 184c are connected, so that the inside of the capping mechanism 181 can be opened to the atmosphere. As a result, after the recording head 22 is negatively pressure-sucked by the capping mechanism 181 and the negative pressure applying unit 70, the negative pressure inside the capping mechanism 181 can be released. Therefore, the load of the operation of separating the capping mechanism 181 from the recording head 22 can be reduced.

[0065] 11 is a front view showing the arrangement of the cap upstream three-way valve 184 and the three-way valve support member 185. As shown in FIGS. 3 and 11, the three-way valve support member 185 is arranged at the end of the cap tray 18 on the right side in the longitudinal direction of the device (+x direction). This makes it possible to attach and detach the three-way valve support member 185 and perform maintenance work on the cap upstream three-way valve 184 when the recording head 22 is in a capped state by the cap mechanism 181. In addition, by moving the cleaning tray 19 to the right side of the device using the device longitudinal direction (x direction) movement means for the cleaning tray 19, maintenance work on the cleaning mechanism 191 is also possible.

[0066] 11, the cap upstream three-way valve 184 is disposed so that the three-way valve atmosphere communication port 184c is positioned higher than the surface of the capping mechanism 181 that caps the recording head 22. This makes it possible to prevent ink or cleaning liquid remaining in the three-way valve downstream flow path 183b from spilling out of the three-way valve atmosphere communication port 184c when the negative pressure inside the capping mechanism 181 is released through the three-way valve atmosphere communication port 184c.

[0067] In this embodiment, the three-way valve support member 185 is located at the end of the cap tray 18 on the right side of the longitudinal direction of the device (+x direction), but it may also be located at the end of the cap tray 18 on the front side of the device (-y direction). In this case, the cap tray 18 needs to be enlarged in the front direction of the device, but it is possible to reduce the size of the cap tray 18 on the right side of the device (+x direction).

[0068] During the negative pressure suction operation by the capping mechanism 181, the rotation speed and drive time of the suction pump are changed depending on the purpose. Specifically, when the recording apparatus is delivered, the rotation speed is set to be fast and the drive time is set to be long to fill the recording head 22 with ink. On the other hand, when the negative pressure suction operation is performed as part of routine maintenance to remove dirt, paper dust, and the like adhering to the recording head, the rotation speed is set to be slow and the drive time is set to be short. Therefore, when the recording apparatus 1 is delivered, the amount of ink discharged from the recording head is large, but during routine maintenance (such as a preliminary ejection operation), the amount of ink discharged is small. It is also known that the amount of cleaning liquid required to clean the capping mechanism 181 varies depending on the amount of ink discharged. Therefore, the cap cleaning operation is changed depending on the negative pressure suction operation, as described below.

[0069] FIG. 12 is a diagram showing the suction sequence when the recording apparatus 1 arrives.

[0070] The suction pump 206 is driven at a rotation speed of S1 [rpm] for 60 seconds (S8001).

[0071] The three-way valve atmosphere communication port 184c is switched to the atmosphere communication state, and the cap mechanism 181 is connected to the atmosphere (S8002).

[0072] Thereafter, the idle suction operation is performed (S8003). The idle suction is a process of sucking ink discharged into the capping mechanism 181 using the suction pump 206 while the capping mechanism 181 is in communication with the atmosphere.

[0073] Finally, the cap cleaning operation is executed with the repetition count set to five (S8004). Details of the cap cleaning operation will be described later with reference to Fig. 14. In the suction sequence when the recording apparatus 1 arrives, a large amount of ink is discharged from the recording head 22, so by repeatedly executing the cap cleaning operation five times, it is possible to prevent the ink remaining in the cap mechanism 181 from solidifying.

[0074] FIG. 13 is a diagram showing a suction sequence during routine maintenance.

[0075] Drive the suction pump 206 at a rotational speed S2 [rpm] (S2 < S1) for 10 seconds (S8011).

[0076] Switch the three-way valve atmosphere communication port 184c to the atmosphere communication state, and communicate the cap mechanism 181 with the atmosphere (S8012). Then, perform an air suction operation (S8013).

[0077] Finally, set the number of repetitions of the cap cleaning operation to 1 and execute it (S8014). In the suction sequence performed during routine maintenance, since the amount of ink discharged from the recording head 22 is small, by performing the cap cleaning operation once, it is possible to prevent the ink remaining in the cap mechanism 181 from sticking.

[0078] FIG. 14 is a diagram showing a cap cleaning sequence.

[0079] When performing the cap cleaning operation in the sequences of FIGS. 12 and 13, set the parameter of the number of repetitions (S8021). For example, as described in FIGS. 12 and 13, when the recording apparatus 1 is loaded, set the number of repetitions to 5, and when performing routine maintenance, set the number of repetitions to 1.

[0080] Subsequently, perform cap opening (separate the cap mechanism 181 from the recording head 22) (S8022).

[0081] Next, switch the three-way valve atmosphere communication port 184c to the non-atmosphere communication state (S8023). Then, drive the cleaning liquid supply pump at a rotational speed S3 [rpm] for 30 seconds to supply the cleaning liquid to the cap mechanism 181 (S8024).

[0082] Thereafter, drive the suction pump 206 at S4 [rpm] (S3 < S4) for 30 seconds to discharge the cleaning liquid including the ink from the cap mechanism 181 (S8025).

[0083] Next, 1 is added to the number of cap cleaning operations i (S8026), which is a variable for managing how many times the cap cleaning operation has been performed.

[0084] Finally, it is determined whether the cap cleaning operation has reached the number of repetitions set in S8021 (S8027). If the number of cap cleaning operations i has not reached the number of repetitions, the operations (S8024 to S8026) after driving the cleaning liquid supply pump 104 are repeated. If the number of cap cleaning operations i has reached the number of repetitions, the three-way valve atmosphere communication port 184c is switched to the atmosphere communication state (S8028), and the sequence ends.

[0085] In this way, by changing the amount of cleaning liquid supplied depending on the amount of ink discharged into the capping mechanism 181, it is possible to prevent ink from adhering to the capping mechanism 181 or the waste liquid flow path while suppressing the use of excessive cleaning liquid in each usage state.

[0086] In this embodiment, the cleaning liquid supply operation and the cleaning liquid discharge operation are repeatedly performed as a set, and the amount of cleaning liquid supplied is changed depending on the number of repetitions. However, the amount of cleaning liquid supplied may also be changed by changing the drive time of the cleaning liquid supply pump during one cleaning liquid supply operation.

[0087] (Second embodiment) In this embodiment, a cap cleaning operation when ink is discharged to the cap mechanism 181 by preliminary ejection will be described.

[0088] The number of preliminary ejections varies depending on the purpose. Here, it is assumed that preliminary ejection A is one preliminary ejection and preliminary ejection B is 100 preliminary ejections. Even in preliminary ejection B, which has a large number of ejections (number of ejections), the amount of ink discharged into the cap mechanism 181 is small compared to the suction sequence described in the first embodiment, so there is no need to perform a cap cleaning operation after each ejection. Therefore, the cumulative number of preliminary ejections (cumulative amount of liquid ejected) is counted to determine the timing of the cap cleaning operation.

[0089] 15 is a diagram showing the cumulative preliminary ejection count sequence. When preliminary ejection A or preliminary ejection B is performed, the cumulative number of preliminary ejections N is counted up (S8031).

[0090] Next, it is determined whether the cumulative number of preliminary ejections N is equal to or greater than a threshold value (1000 in this embodiment). If the cumulative number of preliminary ejections N is equal to or greater than the threshold value, the answer is determined as Yes, and the cap cleaning operation (repeated number of times=1) is immediately performed (S8033). On the other hand, if the cumulative number of preliminary ejections N is less than the threshold value, the cap cleaning operation is not performed.

[0091] In this way, by changing the timing of the cap cleaning operation depending on the amount of ink discharged into the cap mechanism 181 by preliminary ejection, it is possible to prevent ink from adhering to the cap mechanism 181 or the waste liquid flow path while suppressing the use of excessive cleaning liquid in each usage state.

[0092] (Third embodiment) Ink and cleaning fluids usually contain moisturizing components such as water and solvents and moisturizing agents, causing a vapor pressure drop of water. The vapor pressure drop of water is determined by the molar fraction, and the vapor pressure of water in ink and cleaning fluids, i.e., the partial pressure of water vapor, can be calculated using the following formula (1): (1) Water vapor partial pressure in ink = saturated water vapor pressure at that temperature × water mole fraction in ink (%) On the other hand, humidity generally refers to relative humidity (%), which is the partial pressure of water vapor in the air at a certain temperature divided by the saturated water vapor pressure at that temperature. In other words, it can be expressed as follows (2). (2) Partial pressure of water vapor in the atmosphere = saturated water vapor pressure at that temperature × relative humidity (%) The ink and cleaning solution evaporate or absorb moisture to reach equilibrium, filling the difference between the partial pressure of water vapor in the ink or cleaning solution and the partial pressure of water vapor at that temperature and humidity, and the evaporation rate and moisture absorption rate are the difference between the above equations (1) and (2). In other words, it is known to be proportional to the following equation (3). (3) Mole fraction of water in ink and cleaning solution (%) - Relative humidity (%) If the molar fraction of water in the ink or cleaning solution is higher than the relative humidity, the water in the ink or cleaning solution evaporates. If the molar fraction of water in the ink or cleaning solution is lower than the relative humidity, the water in the ink or cleaning solution absorbs water from the atmosphere, and the process progresses until equation (3) becomes 0, reaching equilibrium.

[0093] As shown in FIG. 14, the suction pump 206 discharges the cleaning liquid during the cap cleaning operation, but some cleaning liquid remains in the capping mechanism 181. Since the cap remains open during the printing operation after the cap cleaning operation, the moisture in the cleaning liquid remaining in the capping mechanism 181 evaporates. As the moisture in the cleaning liquid continues to evaporate, the moisture molar fraction in the remaining cleaning liquid becomes lower than the moisture molar fraction in the ink. Therefore, after the printing operation is completed, while the cap is closed (the print head 22 is closed with the capping mechanism 181), the moisture in the ink contained in the nozzles moves to the cleaning liquid remaining in the capping mechanism 181 until an equilibrium state is reached in the cap space. This leads to an increase in the viscosity of the ink in the nozzles, which can lead to ejection defects.

[0094] Therefore, in this embodiment, a method for determining the timing of the cap cleaning operation by estimating the water evaporation rate of the cleaning liquid when the cap is open will be described.

[0095] FIG. 16 is a diagram showing a count sequence of the evaporation rate in the cap.

[0096] First, the current count value Vc of the evaporation rate in the cap is acquired (S8041). The evaporation rate in the cap is a parameter that controls the progress of evaporation of the water from the cleaning liquid remaining in the cap mechanism 181.

[0097] Next, the temperature and humidity of the installation environment of the inkjet recording apparatus 1 are acquired (S8042). The inkjet recording apparatus 1 is equipped with a thermo-hygrometer, and is capable of acquiring the temperature and humidity of the installation environment of the recording apparatus at any timing.

[0098] Next, the evaporation rate coefficient corresponding to the acquired temperature and humidity is derived (S8043). Fig. 17 is a diagram showing an evaporation rate coefficient table corresponding to temperature and humidity. The evaporation rate coefficient is determined from the temperature and humidity at that time.

[0099] After deriving the evaporation rate coefficient, the cap open time between the previous counting process of the evaporation rate in the cap and the current counting process of the evaporation rate in the cap is obtained (S8044).

[0100] After obtaining the cap open time, multiply the evaporation rate coefficient by the cap open time and add the result to the evaporation rate count value inside the cap (S8045). It is determined whether the cap evaporation rate count value is equal to or greater than a predetermined threshold value (75,600 or greater in this example) (S8046). If it is determined that the cap evaporation rate count value is equal to or greater than the threshold value, the cap cleaning operation (repeated count = 1) is executed (S8047). On the other hand, if the cap evaporation rate count value is less than the threshold value, the sequence ends.

[0101] In this way, in this embodiment, the evaporation rate of the cleaning liquid remaining in the capping mechanism 181 is counted to determine the timing of the cap cleaning operation. This makes it possible to prevent excessive evaporation of the cleaning liquid remaining in the capping mechanism 181, which would otherwise cause moisture to migrate from the nozzles, while also suppressing the use of excessive cleaning liquid.

[0102] (Fourth embodiment) In the second embodiment, the timing of the cap cleaning operation is determined based on the cumulative number of preliminary ejections. In the third embodiment, the timing of the cap cleaning operation is determined based on the evaporation rate in the cap. In contrast, in the fourth embodiment, the timing of the cap cleaning operation is determined based on both the cumulative number of preliminary ejections and the evaporation rate in the cap.

[0103] 18 is a diagram showing the cap cleaning determination sequence. The process up to the addition to the cap evaporation rate count value Vc is the same as in FIG. 16 (S8051 to 8055). Thereafter, the cap evaporation rate V is calculated by the following formula (S8056).

[0104] V = evaporation rate count value in the cap Vc ÷ 151200 151200 is a parameter for calculating the evaporation rate, and is a parameter that defines the amount of cleaning liquid remaining in the cap mechanism based on experimental values. If the evaporation rate in the cap V increases too much, the ink will rapidly thicken and will not be able to be sufficiently washed off by the subsequent cap cleaning operation, so the evaporation rate in the cap V is calculated.

[0105] Next, the cumulative number of preliminary ejections N is obtained (S8057). Then, the preliminary ejection ratio Y is calculated using the following formula (S8058). Y = N ÷ (20000 × (1-V)) 20000 is a parameter for comparing the amount of cleaning liquid remaining in the capping mechanism 181 with the amount discharged by preliminary ejection. The ratio of the ink amount by preliminary ejection to the amount of cleaning liquid after evaporation is calculated by subtracting the water evaporation rate V that evaporates while the cap is open from the amount of cleaning liquid remaining in the capping mechanism 181 immediately after the cap cleaning operation. If the ratio of the ink amount by preliminary ejection to the amount of cleaning liquid after evaporation increases too much, the ink will thicken rapidly and will not be able to be sufficiently cleaned by the subsequent cap cleaning operation, so the preliminary ejection ratio Y is calculated.

[0106] After that, it is determined whether the evaporation rate V in the cap exceeds 0.5 (S8059). If it exceeds 0.5, the process proceeds to cap cleaning operation (S8061), and if it does not exceed 0.5, it is determined whether the preliminary discharge ratio Y, which is the next process, exceeds 0.05 (S8060). If it exceeds 0.05, the process proceeds to cap cleaning operation, and if it does not exceed 0.05, the sequence ends. Both thresholds are parameters defined based on experimental values.

[0107] In this embodiment, the timing of the cap cleaning operation is determined by counting the evaporation rate of the cleaning liquid remaining in the capping mechanism 181. This makes it possible to prevent excessive evaporation of the cleaning liquid remaining in the capping mechanism 181, which would otherwise cause moisture to migrate from the nozzles, while also suppressing the use of excessive cleaning liquid.

[0108] The timing of the cap cleaning operation is also determined by calculating the ratio of the amount of cleaning liquid to the cumulative amount of preliminary ejection, taking into consideration the evaporation rate of the cleaning liquid. This makes it possible to prevent ink from adhering to the cap mechanism 181 and the waste liquid flow path, while also suppressing the use of excessive cleaning liquid.

[0109] (Other embodiments) The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0110] The disclosure of this specification includes the following recording device, its control method, program, and storage medium.

[0111] (Item 1) a cap for capping a recording head that ejects liquid; a discharge means for discharging liquid from the recording head into the cap; a supply means for supplying a cleaning liquid to the cap for cleaning the liquid in the cap; a control unit that controls the amount of cleaning liquid supplied to the cap by the supply unit in accordance with the amount of liquid discharged from the recording head to the cap; A recording device comprising:

[0112] (Item 2) 2. The recording apparatus according to item 1, wherein the control means increases the amount of the cleaning liquid supplied to the cap by the supply means as the amount of the liquid discharged from the recording head to the cap increases.

[0113] (Item 3) The recording device described in item 1 or 2, characterized in that the control means performs an operation of supplying the cleaning liquid to the cap and an operation of discharging the cleaning liquid from the cap, and changes the amount of cleaning liquid supplied to the cap by changing the number of times the supply operation and the discharge operation are repeated.

[0114] (Item 4) 4. The recording apparatus according to any one of items 1 to 3, further comprising a suction unit that sucks the liquid from the recording head, and the liquid is discharged from the recording head to the cap by the suction unit.

[0115] (Item 5) 4. The recording apparatus according to any one of items 1 to 3, wherein the liquid is discharged from the recording head to the cap by the recording head ejecting the liquid onto the cap.

[0116] (Item 6) Item 6. The recording apparatus according to item 5, further comprising a counting means for counting the number of times the recording head ejects the liquid onto the cap, wherein the control means controls the supply of cleaning liquid to the cap when the number of times the liquid is ejected counted by the counting means exceeds a threshold value, thereby controlling the amount of cleaning liquid supplied to the cap.

[0117] (Item 7) 7. The recording apparatus according to item 6, wherein the counting means counts the number of preliminary ejection operations from the recording head to the cap.

[0118] (Item 8) 8. The recording device according to any one of items 1 to 7, further comprising an estimation unit that estimates an evaporation rate of the cleaning liquid in the cap while the cap is not capping the recording head, and the control unit supplies the cleaning liquid to the cap when the evaporation rate of the cleaning liquid exceeds a predetermined value.

[0119] (Item 9) 9. The recording apparatus according to item 8, wherein the estimation means estimates the evaporation rate of the cleaning liquid based on an evaporation rate coefficient corresponding to the temperature and humidity in the recording apparatus.

[0120] (Item 10) 10. The recording device described in any one of items 6 to 9, further comprising: a counting means for counting the number of times the recording head ejects the liquid onto the cap; and a second estimation means for estimating the ratio of the liquid contained in the cleaning liquid in the cap by dividing the cumulative liquid ejection amount based on the count by the counting means by the evaporation rate of the cleaning liquid, wherein the control means supplies the cleaning liquid to the cap when the ratio of the liquid exceeds a predetermined threshold.

[0121] (Item 11) A method for controlling a recording apparatus including a cap for capping a recording head that ejects liquid, a discharge unit for discharging liquid from the recording head into the cap, and a supply unit for supplying a cleaning liquid to the cap for cleaning the liquid in the cap, the method comprising: A control method for a recording apparatus, comprising: a control step of controlling the amount of cleaning liquid supplied to the cap by the supply means in accordance with the amount of liquid discharged from the recording head to the cap.

[0122] (Item 12) Item 12. A program for causing a computer to execute the control method according to Item 11.

[0123] (Item 13) A computer-readable storage medium storing a program for causing a computer to execute the control method described in item 11.

[0124] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0125] 1: inkjet recording device, 17: maintenance unit, 18: cap tray, 19: cleaning tray, 22: recording head, 1000: paper feed module, 2000: print module, 3000: drying module, 4000: fixing module, 5000: cooling module, 6000: reversing module, 7000: paper discharge module

Claims

1. a cap for capping a recording head that ejects liquid; a discharge means for discharging liquid from the recording head into the cap; a supply means for supplying a cleaning liquid to the cap for cleaning the liquid in the cap; a control unit that controls the amount of cleaning liquid supplied to the cap by the supply unit in accordance with the amount of liquid discharged from the recording head to the cap; A recording device comprising:

2. 2. The recording apparatus according to claim 1, wherein the control means increases the amount of the cleaning liquid supplied to the cap by the supply means as the amount of the liquid discharged from the recording head to the cap increases.

3. The recording device according to claim 1, characterized in that the control means performs an operation of supplying the cleaning liquid to the cap and an operation of discharging the cleaning liquid from the cap, and changes the amount of cleaning liquid supplied to the cap by changing the number of times the supply operation and the discharge operation are repeated.

4. 2. The recording apparatus according to claim 1, further comprising a suction means for sucking the liquid from the recording head, wherein the liquid is discharged from the recording head to the cap by the suction means.

5. 2. The recording apparatus according to claim 1, wherein the liquid is discharged from the recording head to the cap by the recording head ejecting the liquid onto the cap.

6. The recording apparatus according to claim 5, further comprising a counting means for counting the number of times the liquid is ejected onto the cap by the recording head, and the control means controls the amount of cleaning liquid supplied to the cap by controlling the supply of cleaning liquid to the cap when the number of times the liquid is ejected counted by the counting means exceeds a threshold value.

7. 7. The recording apparatus according to claim 6, wherein said counting means counts the number of preliminary ejection operations from said recording head to said cap.

8. The recording apparatus according to claim 1, further comprising an estimation means for estimating an evaporation rate of the cleaning liquid in the cap while the cap is not capping the recording head, and the control means supplies the cleaning liquid to the cap when the evaporation rate of the cleaning liquid exceeds a predetermined value.

9. 9. The recording apparatus according to claim 8, wherein the estimating means estimates the evaporation rate of the cleaning liquid based on an evaporation rate coefficient corresponding to the temperature and humidity in the recording apparatus.

10. The recording device described in claim 6 further comprises a counting means for counting the number of times the liquid is ejected onto the cap by the recording head, and a second estimation means for estimating the ratio of the liquid contained in the cleaning liquid in the cap by dividing the cumulative liquid ejection amount based on the count by the counting means by the evaporation rate of the cleaning liquid, and the control means supplies the cleaning liquid to the cap when the ratio of the liquid exceeds a predetermined threshold.

11. A method for controlling a recording apparatus including a cap for capping a recording head that ejects liquid, a discharge unit for discharging liquid from the recording head into the cap, and a supply unit for supplying a cleaning liquid to the cap for cleaning the liquid in the cap, the method comprising: A control method for a recording apparatus, comprising: a control step of controlling the amount of cleaning liquid supplied to the cap by the supply means in accordance with the amount of liquid discharged from the recording head to the cap.

12. A program for causing a computer to execute the control method according to claim 11.

13. A computer-readable storage medium storing a program for causing a computer to execute the control method according to claim 11.

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