Inkjet recording device

Abstract

By enabling the print head to be cleaned without removing it from the production line, the usability of the inkjet recording device is improved. [Solution] The inkjet recording device I comprises a print head 1 that houses a nozzle 12, a charging electrode 13, a deflection electrode 15, and a gutter 16 inside and ejects ink; a controller 100 that supplies ink to the print head 1 and sends control signals to the print head 1 to control the nozzle 12, the charging electrode 13, and the deflection electrode 15; and a connecting cable 1000 that fluidly and electrically connects the print head 1 and the controller 100. The print head 1 or the controller 100 is equipped with a solvent supply unit 105 which serves as a liquid supply unit that supplies a liquid to dissolve the ink to the print head 1, and the print head 1 has a diffusion means 18 that diffuses the liquid supplied to the print head 1 from the solvent supply unit 105 and ejected or sprayed within the print head 1.

Description

Technical Field

[0001] The present disclosure relates to an inkjet recording apparatus.

Background Art

[0002] Patent Document 1 discloses an example of a continuous inkjet recording apparatus. Specifically, Patent Document 1 discloses an inkjet recording system including a printing head that houses various components inside, and a cleaning placement unit on which the printing head is placed when cleaning the printing head using a solvent.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the case of a general continuous inkjet recording apparatus, the internal space of the printing head allows ink particles to continue to fly. Therefore, dirt tends to accumulate inside the printing head.

[0005] Generally, electrodes for deflection or charging are built into the printing head. When dirt accumulates on such electrodes, there is a possibility that ink particles may not land at a desired position on the workpiece, or that the ink particles may come into contact with the dirt attached to the electrodes, causing printing irregularities. Therefore, the printing head needs to be cleaned regularly inside.

[0006] So far, the printing head has been cleaned (head cleaning) by the user spraying a solvent into the printing head himself / herself, or by automatically discharging the solvent from a cleaning nozzle provided inside the printing head after placing the printing head on the cleaning placement unit as is known.

[0007] However, all of the head cleaning methods mentioned above require removing the print head from the production line. For example, if the user performs the cleaning manually, after removing the print head, it is necessary to move it to a location where a solvent tray is placed.

[0008] On the other hand, with automatic cleaning that automatically dispenses solvent, after removing the print head, it is necessary to move the print head to a location where a platform for receiving the solvent (also called a cleaning platform, cleaning platform, or cleaning station) is located.

[0009] Thus, the process of removing the print head from the production line, moving it to the cleaning area, and then reinstalling it in its original position after cleaning was not only time-consuming but also carried the risk of dropping the print head during the process. Furthermore, reinstalling the print head was not always easy, and there was a possibility that the printing position would shift each time print head 1 was installed. In addition, frequently stopping the production line could lead to increased downtime. Increased downtime is undesirable because it leads to a decrease in production volume. Concerns had also been raised about securing personnel for the print head installation process and training each person in charge.

[0010] This disclosure has been made in view of the above, and its purpose is to improve the usability of inkjet recording devices by enabling the print head to be cleaned without removing it from the production line. [Means for solving the problem]

[0011] A first aspect of this disclosure relates to an inkjet recording apparatus comprising: a nozzle for ejecting particulate ink; a charging electrode for charging the particulate ink ejected from the nozzle; a deflection electrode for deflecting the flight direction of the ink charged by the charging electrode; and a gutter for collecting the ink that has been made undeflected by the deflection electrode, and a print head for ejecting the ink deflected by the deflection electrode to the outside; a controller for supplying ink to the print head and sending control signals to the print head for controlling the nozzle, the charging electrode, and the deflection electrode; and a connecting cable for fluidically and electrically connecting the print head and the controller.

[0012] According to the first embodiment, the print head or the controller is provided with a liquid supply unit that supplies a liquid for dissolving the ink to the print head, and the print head has a diffusion means for diffusing the liquid supplied from the liquid supply unit to the print head and discharged or sprayed within the print head.

[0013] According to the first embodiment described above, a liquid such as a solvent is diffused into the print head by a diffusion means. This reduces the amount of liquid sprayed when cleaning the print head. Reducing the amount of liquid sprayed suppresses liquid leakage from the print head. By suppressing liquid leakage, it becomes possible to clean the print head with liquid without using a liquid tray, a dedicated stand, etc. This makes it possible to clean the print head without removing it from the production line.

[0014] Alternatively, instead of removing and moving the print head, it might be possible to temporarily place a liquid tray directly beneath the print head. However, moving the tray requires that the tray be readily available. Furthermore, there is a risk of the liquid overflowing from the tray and contaminating the production line. The first embodiment described above eliminates the need for such a tray, thereby improving user convenience.

[0015] Furthermore, according to a second aspect of this disclosure, the diffusion means may diffuse the liquid by crossing the substance with respect to the flight axis of the liquid discharged or sprayed in the print head.

[0016] According to the second embodiment, by intersecting the material with respect to the flight axis of the liquid, it becomes possible to cause the material to collide with the liquid flowing along that flight axis. By causing the material to collide, the liquid can be diffused into the print head.

[0017] Furthermore, according to a third aspect of this disclosure, the diffusion means may cause the substance to cross the flight axis by adjusting at least one of the timing of discharging or spraying the liquid within the print head and the timing of causing the substance to cross the flight axis.

[0018] According to the third embodiment, adjusting at least one of the timing of discharging or spraying liquid within the print head and the timing of intersecting the material with respect to the flight axis is advantageous in causing the material to collide with the liquid flowing along the flight axis. This contributes to the diffusion of the liquid within the print head.

[0019] Furthermore, according to a fourth aspect of this disclosure, the diffusion means may cause the substance to cross the flight axis by adjusting both the timing of discharging or spraying the liquid within the print head and the timing of causing the substance to cross the flight axis.

[0020] According to the fourth embodiment, by adjusting both the timing of discharging or spraying liquid within the print head and the timing of intersecting the material with respect to the flight axis, it becomes possible to more reliably collide the material with the liquid flowing along the flight axis. This contributes to the diffusion of the liquid within the print head.

[0021] Further, according to a fifth aspect of the present disclosure, the diffusion means may have a fluid injection section in the print head for injecting the fluid as the substance, and diffuses the liquid by intersecting the fluid injected from the fluid injection section with respect to the flight axis.

[0022] According to the fifth aspect, by using a fluid as the substance to collide with the liquid, the liquid discharged or injected into the print head can be guided to components in the print head based on the flow direction of the fluid. By guiding the liquid to the components, the dirt adhering to the components becomes easier to fall off. As a result, it is possible to exhibit a sufficient cleaning effect while reducing the injection amount of the liquid.

[0023] [ Further, according to a sixth aspect of the present disclosure, the fluid injection section may inject air as the fluid.

[0024] According to the sixth aspect, by using air as the fluid to collide with the liquid, the liquid discharged or injected into the print head can be sprayed onto components in the print head by the flow of air. By spraying the liquid onto the components, the dirt adhering to the components becomes easier to fall off. As a result, it is possible to exhibit a sufficient cleaning effect while reducing the injection amount of the liquid.

[0025] Further, according to a seventh aspect of the present disclosure, the diffusion means may atomize the liquid by applying the air injected from the fluid injection section to the liquid.

[0026] According to the seventh aspect, the liquid discharged or injected into the print head can be atomized by air and then sprayed onto components in the print head. Atomization of the solvent contributes to an expansion of the cleaning area of the components. As a result, it is possible to exhibit a sufficient cleaning effect while reducing the consumption amount of the liquid.

[0027] Also, by atomizing the solvent, leakage of the liquid can be suppressed regardless of the posture of the printing head. Even when the printing head is not set in a specific posture during cleaning, leakage of the liquid from inside the printing head is suppressed. This is advantageous for cleaning the printing head with the liquid while the printing head is mounted on the production line.

[0028] Furthermore, since leakage of the liquid is suppressed regardless of the posture of the printing head, the degree of freedom in installing the printing head can be increased. This can improve the usability of the inkjet recording apparatus.

[0029] Also, according to the eighth aspect of the present disclosure, the fluid ejection unit may be arranged to eject the air toward the deflection electrode and to interpose the flight axis therebetween and the deflection electrode.

[0030] Generally, dirt caused by ink gradually accumulates on the deflection electrode as the inkjet recording apparatus is repeatedly used. In contrast, according to the eighth aspect, the deflection electrode can be sprayed with the liquid, and the dirt adhering to the deflection electrode is likely to fall off. This is advantageous for achieving a sufficient cleaning effect while reducing the consumption amount of the liquid.

[0031] Also, according to the ninth aspect of the present disclosure, the deflection electrode may be constituted by a grounded first electrode plate and a second electrode plate facing the first electrode plate, and the fluid ejection unit may be arranged on the first electrode plate so as to eject the air toward the second electrode plate.

[0032] According to the ninth aspect, by arranging the fluid ejection unit on the first electrode plate, the fluid ejection unit and the flight axis of the liquid can be made as close as possible. This is advantageous for more surely realizing spraying of the solvent and achieving a sufficient cleaning effect while reducing the consumption amount of the liquid.

[0033] Furthermore, generally, a high voltage is applied to the second electrode plate, which is not grounded. In that case, charged ink will be attracted to the second electrode plate more than to the first electrode plate, which is grounded. The second electrode plate is more prone to accumulating dirt than the first electrode plate.

[0034] In contrast, according to the ninth embodiment, the fluid injection unit sprays liquid toward the second electrode plate during diffusion by the diffusion means. This makes it possible to more reliably clean the second electrode plate, which is assumed to be prone to dirt accumulation.

[0035] Furthermore, according to a tenth aspect of the present disclosure, the second electrode plate may have an inclined surface that is tilted away from the flight axis, and a bent surface that extends from the tip of the inclined surface and is more steeply curved than the inclined surface in the direction away from the flight axis.

[0036] According to the tenth embodiment, by providing a curved surface on the second electrode plate, the solvent sprayed onto the second electrode plate and the ink stains dissolved in the solvent can be guided away from the solvent flowing along the flight axis. This suppresses leakage of solvent and ink stains from the print head and, consequently, improves the usability of the inkjet recording device.

[0037] Furthermore, according to an eleventh aspect of this disclosure, the controller may have an air generating unit that generates air to be injected from the fluid injection unit, and the diffusion means may have a control valve in the print head for controlling the injection of air generated by the air generating unit.

[0038] According to the 11th embodiment described above, by arranging the control valve on the print head and the air generation unit on the controller, the print head can be made more compact by removing the air generation unit from the print head. This improves the convenience of the inkjet recording device.

[0039] Furthermore, according to a twelfth aspect of the present disclosure, the fluid injection unit may include a first injection unit that injects air as the fluid, and a second injection unit that injects auxiliary air to change the injection direction of the air injected from the first injection unit.

[0040] According to the 12th embodiment, the direction of liquid diffusion can be controlled by changing the direction of air injection using auxiliary air. This allows the liquid to be sprayed over a wider area. As a result, the cleaning area within the print head can be expanded, and sufficient cleaning effect can be achieved while reducing liquid consumption.

[0041] Furthermore, according to a thirteenth aspect of this disclosure, the fluid injection unit may inject the liquid as the fluid.

[0042] According to the 13th embodiment, the diffusion means causes the liquid to collide with the liquid being sprayed within the print head. The diffusion direction of the former liquid can be controlled by adjusting the flow rate or velocity of the latter liquid. This allows the liquid to be sprayed over a wider area. As a result, the cleaning area within the print head can be expanded, and sufficient cleaning effect can be achieved while reducing the amount of liquid consumed.

[0043] Furthermore, according to a 14th aspect of this disclosure, the controller may have a cleaning management unit that manages the amount of liquid used during cleaning so that an amount of the liquid corresponding to the fluid sprayed from the fluid injection unit is supplied.

[0044] According to the 14th embodiment described above, the cleaning management unit manages the amount of liquid used. This, combined with the diffusion of the liquid by the diffusion means, can further reduce the amount of liquid consumed.

[0045] Furthermore, according to a 15th aspect of this disclosure, the diffusion means may comprise a movable member that can move to a position intersecting the flight axis of the liquid discharged or sprayed in the print head, and a first moving mechanism that moves the movable member to the position intersecting the flight axis.

[0046] According to the 15th embodiment, by intersecting the moving member with the flight axis of the liquid, it becomes possible to cause the moving member, as a material, to collide with the liquid flowing along that flight axis. By causing the moving member to collide, the liquid can be diffused into the print head.

[0047] Furthermore, according to a sixteenth aspect of this disclosure, the charging electrode or the deflection electrode may be configured to be movable to a position intersecting the flight axis of the liquid discharged or sprayed in the print head, and the diffusion means may consist of the charging electrode or the deflection electrode movable to a position intersecting the flight axis, and a second moving mechanism for moving the charging electrode or the deflection electrode to a position intersecting the flight axis.

[0048] According to the 16th embodiment, by crossing the charged electrode or deflection electrode with respect to the flight axis of the liquid, it becomes possible to cause the charged electrode or deflection electrode, as a material, to collide with the liquid flowing along that flight axis. By causing the charged electrode or deflection electrode to collide, the liquid can be diffused into the print head.

[0049] Furthermore, according to a 17th aspect of this disclosure, the print head may discharge or spray the liquid from at least one of the nozzle and a separate dedicated nozzle.

[0050] Furthermore, according to the 18th aspect of this disclosure, the print head may be equipped with a detachable part that can be attached to and detached from a production line for an object to be printed by the print head.

[0051] Furthermore, according to a 19th aspect of this disclosure, the diffusion means may diffuse the liquid by crossing the material with respect to the flight axis of the liquid discharged or sprayed within the print head while the print head is mounted on the production line by the attachment portion.

[0052] According to the 19th embodiment described above, the print head is subjected to liquid diffusion by the diffusion means while it is mounted on the production line. This eliminates the need to remove the print head from the production line, move it to a cleaning location, and then reinstall it in its original position after cleaning. This not only saves time and effort but also helps to prevent the print head from falling during removal and to prevent a decrease in print cycle time.

[0053] Furthermore, according to a 20th aspect of this disclosure, the liquid supply unit may supply the ink solvent as the liquid to the print head.

[0054] According to the 20th embodiment, a cleaning liquid is not required. This improves the usability of the inkjet recording device. [Effects of the Invention]

[0055] As explained above, this disclosure makes it possible to improve the usability of an inkjet recording device by enabling the print head to be cleaned without removing it from the production line. [Brief explanation of the drawing]

[0056] [Figure 1] Figure 1 is a diagram illustrating the overall configuration of an inkjet recording system. [Figure 2] Figure 2 is a block diagram illustrating the schematic configuration of an inkjet recording device. [Figure 3] Figure 3 is a diagram illustrating the schematic configuration of a print head. [Figure 4A] Figure 4A is a diagram illustrating the schematic configuration of a print head. [Figure 4B]Figure 4B is a diagram illustrating the schematic configuration of the print head. [Figure 5] Figure 5 illustrates the pathways of ink and solvent in an inkjet recording device. [Figure 6] Figure 6 illustrates the overall configuration of the diffusion module. [Figure 7] Figure 7 is a perspective view illustrating the internal structure of a print head. [Figure 8] Figure 8 is a flowchart illustrating the process for determining whether or not head cleaning is necessary. [Figure 9] Figure 9 is a flowchart illustrating the process for determining whether or not head cleaning is necessary. [Figure 10] Figure 10 is a flowchart illustrating the specific process of head cleaning. [Figure 11] Figure 11 is a graph illustrating the relationship between air flow rate and solvent ejection timing. [Figure 12A] Figure 12A is a diagram corresponding to Figure 4A, showing a second embodiment of the inkjet recording device. [Figure 12B] Figure 12B is a diagram corresponding to Figure 4B showing the second embodiment. [Figure 13] Figure 13 is a diagram illustrating the internal structure of the print head according to the second embodiment. [Figure 14A] Figure 14A is a diagram corresponding to Figure 4A, showing a third embodiment of the inkjet recording device. [Figure 14B] Figure 14B is a diagram corresponding to Figure 4B showing the third embodiment. [Figure 15] Figure 15 is a diagram corresponding to Figure 5 showing the third embodiment. [Figure 16] Figure 16 illustrates the control of the diffusion direction in the third embodiment. [Figure 17] Figure 17 is a flowchart illustrating the specific head cleaning process in the third embodiment. [Figure 18A] Figure 18A is a diagram corresponding to Figure 4A, showing a fourth embodiment of the inkjet recording device. [Figure 18B] Figure 18B is a diagram corresponding to Figure 4B showing the fourth embodiment. [Figure 19] Figure 19 is a corresponding diagram to Figure 5 showing the fourth embodiment. [Figure 20] Figure 20 illustrates the control of the diffusion direction in the fourth embodiment. [Figure 21] Figure 21 is a flowchart illustrating the specific head cleaning process in the fourth embodiment. [Figure 22A] Figure 22A is a diagram corresponding to Figure 4A showing a fifth embodiment of the inkjet recording device. [Figure 22B] Figure 22B is a diagram corresponding to Figure 4B showing the fifth embodiment. [Figure 23] Figure 23 is a corresponding diagram to Figure 5 showing the fifth embodiment. [Figure 24] Figure 24 illustrates the control of the diffusion direction in the fifth embodiment. [Figure 25] Figure 25 is a flowchart illustrating the specific head cleaning process in the fifth embodiment. [Figure 26A] Figure 26A is a diagram corresponding to Figure 4A, showing a sixth embodiment of the inkjet recording device. [Figure 26B] Figure 26B is a diagram corresponding to Figure 4B showing the sixth embodiment. [Figure 26C] Figure 26C is a diagram corresponding to Figure 4B showing the sixth embodiment. [Figure 27] Figure 27 is a diagram corresponding to Figure 5 showing the sixth embodiment. [Figure 28] Figure 28 is a flowchart illustrating the specific head cleaning process in the sixth embodiment. [Figure 29] Figure 29 is a side view illustrating the mounting section of the print head. [Figure 30] Figure 30 is a diagram illustrating the diffusion method related to this disclosure. [Figure 31] Figure 31 is a flow path diagram extracted from Figure 5, showing the elements related to print head cleaning. [Modes for carrying out the invention]

[0057] [First Embodiment] Hereinafter, each embodiment of this disclosure will be described in order, starting with the first embodiment, with reference to the drawings. Note that the following description is illustrative. The term "first embodiment" may sometimes be simply referred to as "embodiment."

[0058] In this specification, an industrial inkjet printer is described as an example of an inkjet recording device. However, the technology disclosed herein can be applied to general devices configured to eject particulate ink and land it on a workpiece or other object to be printed on, regardless of whether they are called an inkjet recording device or an industrial inkjet printer.

[0059] Furthermore, this specification describes printing using an inkjet recording device, but the term "printing" as used herein includes all processing processes that utilize inkjet technology, such as printing characters and marking graphics.

[0060] <Overall Structure> Figure 1 is a diagram illustrating the overall configuration of the inkjet recording system S. Figure 2 is a diagram illustrating the schematic configuration of the inkjet recording device I, and Figures 3, 4A, and 4B illustrate the schematic configuration of the print head 1 in the inkjet recording device I. Figure 5 is a diagram illustrating the ink and solvent pathways in the inkjet recording device I. Figure 29 is a side view illustrating the attachment / detachment section 9 of the print head.

[0061] The inkjet recording system S illustrated in Figure 1 is installed, for example, on a transport line L in a factory, and is configured to sequentially print on each object W to be printed as it flows along the transport line L. However, the application of this disclosure is not limited to the inkjet recording system S. It can be applied to printing systems using methods other than automation. The transport line L can be, for example, a belt conveyor. Note that the term "object to be printed" may also be referred to as "object to be printed" in the following description.

[0062] Specifically, the inkjet recording system S comprises an inkjet recording device I that prints by depositing particulate ink (ink droplets) onto a printing surface W, and an operating terminal 800 and external equipment 900 connected to the inkjet recording device I. Note that the operating terminal 800 and external equipment 900 are not mandatory.

[0063] The inkjet recording device I illustrated in Figures 1 to 3 comprises a print head 1 that ejects ink droplets from a nozzle 12 and deposits the ink droplets onto a printing surface W, a controller 100 that supplies control signals, ink, and solvent to the print head 1, and a connecting cable 1000 that connects the print head 1 and the controller 100. The controller 100 controls the trajectory of the ink droplets by supplying control signals to the print head 1. This adjusts the landing position of the ink droplets on the printing surface W, thereby achieving the desired printing. The print head 1 is fixed in a predetermined position by a support member 2 or the like.

[0064] Inkjet printer I is a continuous inkjet printer (CIJ). That is, to prevent clogging caused by ink evaporation (especially clogging of nozzle 12), ink is constantly circulating inside inkjet printer I even when printing is not in progress, as long as inkjet printer I is operating. By adopting a continuous system, it becomes possible to use fast-drying ink without causing ink clogging.

[0065] Furthermore, the inkjet recording apparatus I according to this embodiment is capable of adjusting the ink concentration (viscosity) by mixing the solvent and the ink.

[0066] Furthermore, in this embodiment, the inkjet recording apparatus I supplies a liquid that dissolves the ink from the controller 100 to the print head 1 during the cleaning process described later. This liquid is used for cleaning the inside of the print head 1. In this embodiment, the solvent used to adjust the ink concentration (viscosity) is used in the liquid that dissolves the ink and is used for cleaning the inside of the print head 1.

[0067] When a solvent is used in the liquid, the solvent used to clean the print head 1 can be recovered as needed and reused to adjust the ink concentration (viscosity) or reused for further cleaning of the print head 1.

[0068] It is not essential to use a solvent to adjust the ink's concentration (viscosity) in the cleaning solution. Any liquid capable of dissolving ink, such as ethanol or other organic solvents, can be used for the cleaning process.

[0069] To achieve ink circulation, the print head 1 is equipped with a gutter 16 that recovers the ink or solvent discharged from the nozzle 12, in addition to the nozzle 12 (see Figure 3). The ink or solvent sent from the controller 100 to the print head 1 is discharged from the nozzle 12 and recovered by the gutter 16. The recovered ink or solvent is then sent back to the controller 100 for reuse. By repeating this process, the ink can be circulated.

[0070] On the other hand, the operating terminal 800 has, for example, a central processing unit (CPU) and a memory device, and is connected to the controller 100. This operating terminal 800 functions as a terminal for setting print settings and displaying print-related information to the user.

[0071] The print settings configured by the operating terminal 800 are output to the controller 100 and stored in its storage unit 102. In addition to, or instead of, the operating terminal 800 may store the print settings in the storage unit 102 of the controller 100.

[0072] In addition to the content of the string to be printed, the print settings according to this embodiment may also include conditions and parameters related to head cleaning, as described later.

[0073] The operating terminal 800 can be integrated into, for example, the controller 100. In this case, the term "operating terminal" would not be used; instead, a term such as "control unit" would be used.

[0074] External devices 900 are connected to the controller 100 as needed. In the example shown in Figures 1 and 2, the external devices 900 include a work detection sensor 901, a transport speed sensor 902, and a programmable logic controller (PLC) 903.

[0075] Specifically, the workpiece detection sensor 901 detects the presence or absence of the object to be printed W on the transport line L and outputs a signal (detection signal) indicating the detection result to the controller 100. The detection signal output from the workpiece detection sensor 901 functions as a trigger (print trigger) to start printing.

[0076] The transport speed sensor 902 is composed of, for example, a rotary encoder and can detect the transport speed of the object to be printed W. The transport speed sensor 902 outputs a signal (detection signal) indicating the detection result to the controller 100. Based on the detection signal input from the transport speed sensor 902, the controller 100 controls the timing of ink droplet ejection from the print head 1, etc.

[0077] Furthermore, as illustrated in Figure 2, the PLC903 is electrically connected to the controller 100. The PLC903 is used to control the inkjet recording system S according to a predetermined sequence.

[0078] In addition to the devices and equipment described above, the inkjet recording device I may also be connected to devices for operation and control, computers for various other processing tasks, storage devices, peripheral devices, etc. The connection method may be either wired or wireless.

[0079] <Controller 100> The controller 100 is configured to supply ink to the print head 1 and to send control signals to the print head 1 for controlling the components of the print head 1. Here, the components of the print head 1 include the nozzle 12, the charging electrode 13, and the deflection electrode 15, which will be described later. The controller 100 also supplies the print head 1 with a solvent for diluting the ink, in addition to the ink for printing.

[0080] Specifically, the controller 100 according to this embodiment includes, as components related to electrical control, a storage unit 102 for storing the aforementioned print settings, a control unit 101 for controlling each part of the controller 100 and the print head 1, an operation display unit 103 for receiving user operations and displaying information to the user, and a power supply unit 121 for guiding power supplied from an external source to the control unit 101.

[0081] The controller 100 also includes components related to the supply of ink, etc., such as an ink supply unit 104, a solvent supply unit 105, and an ink tank 106. These components are fluidly connected to the print head 1 directly or indirectly. In this embodiment at least, the controller 100 houses the ink supply unit 104, the solvent supply unit 105, and the control unit 101 internally.

[0082] The ink supply unit 104 has an ink reservoir 42 that removably receives an ink cartridge 41 in which ink is contained. The ink supply unit 104 supplies ink to the print head 1.

[0083] On the other hand, the solvent supply unit 105 has a solvent reservoir 52 that detachably receives a solvent cartridge 51 containing the solvent. The solvent supply unit 105 supplies the solvent to the print head 1.

[0084] Furthermore, during the cleaning process described below, the solvent supply unit 105 supplies the print head 1 with a liquid (solvent in this embodiment) that dissolves the ink. The solvent supply unit 105 is an example of a "liquid supply unit" according to this embodiment.

[0085] It is not essential that the solvent supply unit 105 also functions as a liquid supply unit. The liquid supply unit can be located on the print head 1 or the controller 100. For example, a module capable of supplying solvent (liquid) may be located on the print head separately from the solvent supply unit 105. In that case, the module located on the print head 1 would function as the liquid supply unit in that example.

[0086] If a liquid supply unit is provided separately from the solvent supply unit 105, the liquid supply unit may supply the same solvent to the print head 1 as the solvent supplied by the solvent supply unit 105, or it may supply a different liquid to the print head 1 than the solvent supplied by the solvent supply unit 105.

[0087] Furthermore, it is not essential to place the liquid supply unit within the controller 100, as is the case with the solvent supply unit 105. A module capable of supplying solvent (liquid) may be configured to be mounted on the outer surface of the print head 1 or the controller 100.

[0088] In other words, it is not necessary for the liquid supply unit to be an element of the print head 1 and controller 100. The liquid supply unit may be an independent element from the print head 1 and controller 100.

[0089] Furthermore, the ink tank 106 stores the ink from the ink cartridge 41 received in the ink reservoir 42 and the solvent from the solvent cartridge 51 received in the solvent reservoir 52 as printing ink. Here, "printing ink" refers to a mixture of solvent and ink (for example, ink whose concentration has been adjusted by the solvent).

[0090] The print head 1 then prints using printing ink from the ink tank 106. The print head 1 also cleans the nozzles 12 and other parts inside the print head 1 with solvent supplied from the solvent supply unit 105, bypassing the ink tank 106.

[0091] In addition, the controller 100 according to this embodiment has an air generating unit 108 as an element related to the cleaning process within the print head 1. The air generating unit 108 is housed, for example, inside the controller 100. Details of the air generating unit 108 will be described later. Note that it is not essential to place the air generating unit 108 inside the controller 100.

[0092] Furthermore, the cleaning process of the print head 1 referred to here means supplying the liquid (in this embodiment, a solvent for concentration adjustment) from the solvent supply unit 105, which acts as a liquid supply unit, to the print head 1, and spraying and diffusing the liquid within the print head 1. Hereinafter, this cleaning process will also be referred to as "head cleaning." By performing head cleaning, the inside of the print head 1, in particular, the components housed inside the print head 1 can be cleaned.

[0093] During head cleaning, the solvent supplied to the print head 1 is diffused by the diffusion module 70 of the inkjet recording device I. The diffusion module 70 according to this embodiment consists of the air generating unit 108 and the diffusion means 18 of the print head 1. Details of the diffusion means 18 will be described later, similar to the details of the air generating unit 108.

[0094] The control unit 101, the ink supply unit 104, and the solvent supply unit 105 may be configured as separate units. The storage unit 102 may also be configured as a separate unit from the ink supply unit 104 and the solvent supply unit 105. The operation display unit 103 may also be configured as a separate unit from the ink supply unit 104 and the solvent supply unit 105. In these cases as well, the components can be combined to form the controller 100.

[0095] Furthermore, considering the ink supply unit 104 and the ink tank 106 as independent components is merely a classification for convenience. From the perspective of being related to ink supply, the ink tank 106 could also be considered an element of the ink supply unit 104.

[0096] (Storage unit 102) The storage unit 102 stores the print settings set via the operation display unit 103 (described later) or the operation terminal 800, and is configured to output the stored print settings to the control unit 101 based on an external control signal. The storage unit 102 may also store information related to head cleaning. The information related to head cleaning includes information related to the processing performed by the cleaning control unit 101a. The information related to the processing performed by the cleaning control unit 101a includes the cleaning pattern for head cleaning and the cleaning time for head cleaning.

[0097] Specifically, the storage unit 102 is configured using volatile memory, non-volatile memory, SSD (Solid State Drive), HDD (Hard Disk Drive), etc., and can temporarily or continuously store information indicating print settings. If the operation terminal 800 is incorporated into the controller 100, the operation terminal 800 may also function as the storage unit 102.

[0098] (Control Unit 101) The control unit 101 is a processing unit that controls the supply of ink from the ink supply unit 104 to the print head 1, as well as the supply of solvent from the solvent supply unit 105 to the print head 1.

[0099] In detail, the control unit 101 controls at least the ink supply unit 104 and solvent supply unit 105 in the controller 100, and the nozzle 12, charging electrode 13, and deflection electrode 15 in the print head 1, based on the print settings stored in the memory unit 102. By controlling each part, the control unit 101 ensures that printing on the object W is performed at a predetermined timing.

[0100] More specifically, the control unit 101 includes, for example, a CPU, memory, and input / output bus, and generates control signals based on signals indicating information input via the operation display unit 103 or the operation terminal 800, and signals indicating print settings read from the storage unit 102. The control unit 101 controls printing on the object to be printed W by outputting the generated control signals to the controller 100 and the respective parts of the inkjet recording device I.

[0101] For example, when printing on the object W, the control unit 101 reads the printing content stored in the memory unit 102 and generates a control signal based on that printing content. The control unit 101 then outputs this control signal to the charged electrode 13 to set the flight direction of the ink droplets so that the landing position corresponds to the printing content.

[0102] -Other functional elements in the control unit 101- In addition, the control unit 101 according to this embodiment includes a cleaning control unit 101a, as illustrated in Figure 2, as a functional element for performing head cleaning processes. Details of the cleaning control unit 101a will be described later.

[0103] (Operation display section 103) As shown in Figure 1, the operation display unit 103 comprises a display unit 103a that displays information to the user and an operation unit 103b that receives operations from the user. The operation display unit 103 can be provided, for example, in the housing that constitutes the controller 100, but it may also be configured separately from the housing and set in a different location from the housing. Furthermore, if an operation terminal 800 is incorporated into the controller 100, the operation terminal 800 may also serve as the operation display unit 103.

[0104] The display unit 103a displays various information related to the inkjet recording device I. The display unit 103a is composed of, for example, a liquid crystal display panel or an organic EL display panel, and changes its display mode in response to control signals from the control unit 101. The display unit 103a can display user interfaces for operating various parts of the inkjet recording system S, display user interfaces for setting print settings, and display user interfaces related to head cleaning.

[0105] The operation unit 103b is composed of, for example, a touch-sensitive control panel, buttons, switches, etc. When a user operates the operation unit 103b, information corresponding to that operation input (operation information) is input to the control unit 101, and the control unit 101 can detect what kind of operation was performed. For example, by operating the operation unit 103b, the user can switch the power of the inkjet recording device I on or off, perform various settings, input information, etc.

[0106] The operation display unit 103 can also be used to set print settings, similar to the operation terminal 800 mentioned above. The print settings set by the operation display unit 103 are output to the controller 100 and stored in its memory unit 102. The following description assumes that the user operates the operation display unit 103, but the operation terminal 800 can also be used instead of the operation display unit 103.

[0107] (Ink supply unit 104) The ink supply unit 104 supplies ink from the ink cartridge 41 to the nozzles 12 of the print head 1 as printing ink. At that time, the ink from the ink supply unit 104 is supplied to the print head 1 via the ink tank 106.

[0108] Specifically, the ink supply unit 104 according to this embodiment has, as its main components, the aforementioned ink cartridge 41 and ink reservoir 42, an ink hollow needle 43 as a hollow needle, and an ink supply pipe 44. The ink hollow needle 43 fluidly connects the ink cartridge 41 and the ink supply pipe 44. The ink supply pipe 44 fluidly connects the ink cartridge 41 and the print head 1 via the ink hollow needle 43 and a connecting cable 1000. An ink tank 106 is located in the middle of the ink supply pipe 44 from the ink hollow needle 43 to the print head 1.

[0109] Of these, the ink cartridge 41 contains ink. The ink reservoir 42 removably receives this ink cartridge 41. By replacing the ink cartridge 41 in the ink reservoir 42, the ink can be replenished in the ink tank 106. In other words, the inkjet recording device I according to this embodiment is configured as a so-called "cartridge type" inkjet printer.

[0110] As shown only in Figure 5, the ink reservoir 42 is equipped with a first mounting sensor SW1 that detects when an ink cartridge 41 or a solvent cartridge 51 is attached to the ink reservoir 42.

[0111] The hollow needle 43 for ink accesses the ink in the ink cartridge 41 when the ink reservoir 42 accepts the ink cartridge 41 (when the ink cartridge 41 is installed in the ink reservoir 42).

[0112] The ink supply pipe 44, together with the connection cable 1000 described later, forms a path for supplying printing ink to the print head 1. The path formed by the ink supply pipe 44 allows ink to be circulated between the print head 1 and the controller 100.

[0113] Furthermore, as described later, the ink supply pipe 44 is equipped with a plurality of on-off valves, including the first valve V1, and a plurality of pumps, including the first pump P1. Each of these on-off valves is composed of a solenoid valve. Each on-off valve can open and close in response to a control signal output from the control unit 101, thereby controlling the flow of ink. On the other hand, each pump can pump ink under pressure in response to a control signal output from the control unit 101, and in the same way as the on-off valves, it can control the flow of ink. Note that at least some of the on-off valves (for example, the first valve V1, the eighth valve V8, the eleventh valve V11, and the eighteenth valve V18 in Figure 5) may be manual cocks instead of solenoid valves.

[0114] (Solvent supply unit 105) The solvent supply unit 105 either supplies the solvent from the solvent cartridge 51 to the ink tank 106 in the same way as the ink, or supplies the solvent alone to the nozzle 12. The former solvent, by adjusting the concentration of the ink, is supplied to the print head 1 together with the ink to form the printing ink.

[0115] Here, when the solvent is combined with the ink to form printing ink (i.e., when printing is performed on the print head 1), the solvent from the solvent supply unit 105 is guided to the nozzle 12 via the ink tank 106. On the other hand, when the solvent is supplied by itself (for example, when performing the head cleaning described later), the solvent from the solvent supply unit 105 is guided to the nozzle 12 without going through the ink tank 106.

[0116] Of these, the solvent cartridge 51 contains the solvent. The solvent reservoir 52 removably receives this solvent cartridge 51. By replacing the solvent cartridge 51 in the solvent reservoir 52, the solvent for concentration adjustment and the solvent for cleaning can be replenished. In other words, the inkjet recording device I according to this embodiment is configured as an inkjet printer with a "cartridge type" solvent as well.

[0117] Specifically, the solvent supply unit 105 according to this embodiment has, as its main components, the aforementioned solvent cartridge 51 and solvent reservoir 52, a hollow solvent needle 53, and a solvent supply pipe 54. The hollow solvent needle 53 fluidically connects the solvent cartridge 51 and the solvent supply pipe 54. The solvent supply pipe 54 fluidly connects the solvent cartridge 51 and the print head 1, and the solvent cartridge 51 and the ink tank 106, respectively, via the hollow solvent needle 53 and the connecting cable 1000.

[0118] Of these, the solvent cartridge 51 contains the solvent. The solvent reservoir 52 removably receives this solvent cartridge 51. By replacing the solvent cartridge 51 in the solvent reservoir 52, the solvent for concentration adjustment and the solvent for cleaning can be replenished. In other words, the inkjet recording device I according to this embodiment is configured as an inkjet printer with a "cartridge type" solvent as well.

[0119] As shown only in Figure 5, the solvent reservoir 52 is equipped with a second mounting sensor SW2 that detects when a solvent cartridge 51 or an ink cartridge 41 is attached to the solvent reservoir 52.

[0120] The hollow needle 53 for the solvent accesses the solvent in the solvent cartridge 51 when the solvent reservoir 52 accepts the solvent cartridge 51 (when the solvent cartridge 51 is installed in the solvent reservoir 52).

[0121] The solvent supply pipe 54, together with the connecting cable 1000 described later, constitutes a path for supplying solvent to the ink tank 106 and supplying solvent to the print head 1 without the ink tank 106 present. Through these paths, printing ink can be generated from the ink and solvent, and the print head 1 can be cleaned with the solvent.

[0122] It should be noted that the classification of ink supply pipe 44 and solvent supply pipe 54 is merely a convenient classification made for the sake of brevity in the explanation. The ink supply pipe 44 and solvent supply pipe 54 are practically inseparable, as they are either connected to each other or one serves the other.

[0123] As described below, the solvent supply pipe 54 is equipped with multiple on-off valves, including the 12th valve V12, and multiple pumps, including the 2nd pump P2. Each of these on-off valves is a solenoid valve. Each on-off valve opens and closes in response to a control signal output from the control unit 101, thereby controlling the flow of the solvent. On the other hand, each pump pumps the solvent under pressure in response to a control signal output from the control unit 101, and can control the flow of the solvent in the same way as the solenoid valves. As mentioned above, manual cocks may be used instead of solenoid valves.

[0124] (Ink Tank 106) The ink tank 106 is configured to store ink from the ink cartridge 41 and solvent from the solvent cartridge 51. More specifically, the ink tank 106 consists of a container that holds ink whose concentration (viscosity) has been adjusted by the solvent, i.e., a mixture of ink and solvent.

[0125] The printing ink supplied from the ink tank 106 to the nozzle 12 lands on the surface of the object to be printed W when printing is in progress, while when not printing, it is collected by the gutter 16 and sent back to the ink tank 106. This enables the circulation of the printing ink.

[0126] Furthermore, the solvent supplied to the nozzle 12 for cleaning can also be collected by the gutter 16 and then sent to the ink tank 106 via, for example, a solvent-dedicated conditioning tank (not shown) for reuse in adjusting the ink concentration.

[0127] Furthermore, the ink tank 106 is equipped with a storage sensor 106a for detecting the liquid level (so-called liquid surface level) inside the tank. The storage sensor 106a is electrically connected to the control unit 101 and inputs its detection signal to the controller 100. The storage sensor 106a may be configured as an electrode-type level sensor, a float-type level sensor, or a capacitive-type level sensor.

[0128] (Power supply section 121) The power supply unit 121 is interposed between the commercial power supply 700 and the control unit 101, and can relay the power supplied from the commercial power supply 700 and supply it to the control unit 101.

[0129] <Connection Cable 1000> The connecting cable 1000 fluidly and electrically connects the print head 1 and the controller 100. The connecting cable 1000 is flexible and is connected to the upper end of the print head 1 (see Figure 1). One end of the connecting cable 1000 is connected to the print head 1, and the other end is connected to the controller 100.

[0130] In detail, the connection cable 1000 is composed of a power supply cable for sending and receiving control signals between the print head 1 and the controller 100, an ink tube 1001 for sending and receiving ink between the two, and a solvent tube 1002 for sending and receiving solvent between the two (see Figure 3).

[0131] More specifically, the ink tube 1001 for sending and receiving ink between the print head 1 and the controller 100 is continuous with the ink supply pipe 44. The solvent tube 1002 for sending and receiving ink between the print head 1 and the controller 100 is continuous with the solvent supply pipe 54.

[0132] <Print head 1> The print head 1 ejects ink (printing ink) whose concentration has been adjusted based on the control signals, ink, and solvent supplied from the controller 100, in the form of particulate ink (hereinafter also referred to as "ink particles"). The print head 1 deflects the flight direction of the ejected ink particles and causes the deflected ink particles to land on the surface of the object to be printed W, thereby enabling printing on the object W. The details of the printing at that time follow the printing settings described above. The print head 1 can sequentially print on each of the objects to be printed W according to the printing settings.

[0133] Specifically, as shown in Figure 3, the print head 1 according to this embodiment includes a pressurizer 11, a nozzle 12, a charging electrode 13, a deflection electrode 15, a gutter 16, a cleaning nozzle 17, a shutter 21, a suction device 22, a filter 23, and an attitude sensor 24. The pressurizer 11 pressurizes the printing ink, turning it into particulate ink. The nozzle 12 discharges the particulate ink. The charging electrode 13 charges the particulate ink discharged from the nozzle 12. The deflection electrode 15 deflects the flight deflection of the printing ink charged by the charging electrode 13. The gutter 16 collects the printing ink that has been de-deflected by the deflection electrode 15, or the solvent discharged from the nozzle 12. Note that the shutter 21, suction device 22, filter 23, and attitude sensor 24 are not essential.

[0134] In addition, as elements related to the acquisition of various parameter values, the print head 1 is equipped with a charge detection sensor 14 that monitors the charge state of the printing ink, and a gutter sensor 16b that detects whether or not ink is in the gutter 16.

[0135] The print head 1 houses a pressurizer 11, a nozzle 12, a charging electrode 13, a charge detection sensor 14, a deflection electrode 15, a gutter 16, and a cleaning nozzle 17, and ejects printing ink deflected by the deflection electrode 15 to the outside. The inkjet recording device I according to this embodiment prints by causing the ink deflected by the deflection electrode 15 to land on the object to be printed.

[0136] In detail, the print head 1 houses a pressurizer 11, a nozzle 12, a charging electrode 13, a charge detection sensor 14, a deflection electrode 15, a gutter 16, a gutter sensor 16b, and a cleaning nozzle 17, and includes a housing 10 that partitions the space S1 in which ink particles fly. This print head 1 can eject ink particles deflected by the deflection electrode 15 to the outside of the housing 10 via the space S1.

[0137] As illustrated in Figure 3, the housing 10 extends in the vertical direction of the paper. In the following description, the longitudinal direction of the housing 10 will be simply referred to as the "vertical direction," while the two directions perpendicular to this vertical direction will be referred to as the "front-back direction" and the "left-right direction," respectively. In other figures as well, the directions corresponding to these will be referred to as the "vertical direction," the "front-back direction," and the "left-right direction," respectively.

[0138] Here, "top" refers to the upper part of the page in Figure 3, and "bottom" refers to the lower part of the page. Similarly, "front" refers to the front part of the page in Figure 3 (specifically, the front left), "back" refers to the back part of the page (specifically, the back right), "left" refers to the left side of the page (specifically, the upper left), and "right" refers to the right side of the page (specifically, the lower right). In other figures as well, the corresponding areas are called "top," "bottom," "front," "back," "left," and "right," respectively.

[0139] Furthermore, the print head 1 is not necessarily oriented vertically (in the direction of gravity). The print head 1 can also be oriented horizontally.

[0140] In the following explanation, "up and down" will be tentatively defined as referring to the vertical direction or approximately vertical direction. For example, the top of the page in Figure 3 corresponds to "upward along the vertical direction" or "upward along approximately vertical direction," and the bottom of the page in the same figure corresponds to "downward along the vertical direction" or "downward along approximately vertical direction."

[0141] Furthermore, the print head 1 has an ink outlet 10a for ejecting ink deflected by the deflection electrode 15 to the outside. As shown in Figure 3, this ink outlet 10a opens to the lower surface of the housing 10 which forms the outer shape of the print head 1. Hereafter, the ink outlet 10a will also be simply referred to as the outlet 10a. The ink droplets are ejected from this outlet 10a toward the bottom of the housing 10.

[0142] As shown in Figure 1, the print head 1 during printing is supported, for example, by a support member 2. When the print head 1 is supported by the support member 2, its ejection port 10a is positioned to face the printing surface of the object W from above. This is an example of the installation location of the print head 1 when printing is performed by the inkjet recording device I.

[0143] In detail, the print head 1 is equipped with a detachable part 9 that is attached to and detached from the support member 2 (see Figure 29). As shown in Figure 29, this detachable part 9 is located on the back (rear) side of the housing 10. The print head 1 is supported by the support member 2 via the detachable part 9.

[0144] On the other hand, as shown in Figure 1, the support member 2 in this embodiment has a fixed relative position to the production line (conveyor line L) of the object to be printed W by the print head 1. Therefore, the attachment / detachment part 9 is attached to and detached from the support member 2, and through the support member 2, it is attached to and detached from the production line (conveyor line L) of the object to be printed W.

[0145] The following describes each part of print head 1 in order.

[0146] (Pressurizer 11) As illustrated in Figure 3, the pressurizer 11 is positioned near the upper end of the housing 10 in the flight space S1. Printing ink is supplied to this pressurizer 11 from the ink tank 106 of the controller 100 via a connecting cable 1000.

[0147] The pressurizer 11 pressurizes the ink liquid supplied from the ink tank 106. The pressurized ink from the pressurizer 11 is supplied to the nozzle 12. Although not shown in the figures, the pressurizer 11 in this embodiment is grounded.

[0148] (Nozzle 12) The nozzle 12 is connected to the lower end of the pressurizer 11 and is positioned with its opening end (printing ink) facing downwards. The nozzle 12 has a piezoelectric element (e.g., a piezo element) that imparts vertical vibrations to the ink, and after the pressurizer 11 pressurizes the ink, it is discharged from the discharge port (opening end). Due to these vibrations, the ink liquid discharged from the nozzle 12 is atomized after a predetermined time from the discharge timing.

[0149] Here, the printing ink ejected from the nozzle 12 without vibration (without excitation) flows as an axial "ink shaft". On the other hand, the printing ink ejected from the nozzle 12 after vibration (excitation) is axial immediately after ejection from the nozzle 12, but becomes granular as it moves away from the nozzle 12. The granular printing ink falls as so-called "ink droplets". Regardless of whether it is an ink shaft or ink droplets, the printing ink passes through the charged electrode 13. Note that by ejecting the solvent alone from the nozzle 12, the solvent can be made to flow in an axial manner. Hereafter, such an axial solvent will also be called a "solvent shaft". The central axes of the ink shaft and the solvent shaft are as shown by the dashed line Ax in Figure 4A.

[0150] The central axis Ax of the ink axis and solvent axis can be rephrased as the "flight axis" of the ink and solvent, respectively. The flight axis Ax of the ink and solvent extends to connect the nozzle 12 and the gutter 16. More specifically, the flight axis Ax extends vertically along the longitudinal direction of the print head 1. This flight axis Ax is an example of the "liquid flight axis" in this embodiment.

[0151] Furthermore, if the nozzle 12 is equipped with a piezoelectric element, the atomization of the ink can be controlled through the voltage (piezoelectric voltage) applied to the piezoelectric element. In this embodiment, the controller 100 is configured to apply a controllable piezoelectric voltage to the piezoelectric element of the nozzle 12.

[0152] The solvent supplied to clean the inside of the print head 1 passes through the pressurizer 11 and the nozzle 12 in sequence, and is ejected from the tip of the nozzle 12. The ejected solvent then flows axially along the flight axis Ax and passes through the charged electrode 13.

[0153] Furthermore, a suction path 47, shown in Figure 5, is connected to the nozzle 12, for example, as a return path to release pressure inside the print head 1 when the inkjet recording device I is shut down. Solvents can also be drawn out of the nozzle 12 through this suction path 47.

[0154] (Charged electrode 13) As illustrated in Figure 3, the charging electrode 13 is composed of a pair of electrically conductive metal plates and is positioned below the nozzle 12. Here, the pair of metal plates constituting the charging electrode 13 are fixed to the housing 10 in a position where their respective longitudinal directions are aligned vertically and they face each other horizontally. The distance between the pair of metal plates is set to be greater than the particle size of the ink ejected from the nozzle 12, so that the printing ink ejected from the nozzle 12 passes between the pair of metal plates. Note that the metal plates constituting the charging electrode 13 do not necessarily have to be a pair.

[0155] A potential (positive potential) is applied to the charging electrode 13 at least when the printing operation is performed. This creates a potential difference between the pressurizer 11 and the charging electrode 13, making it possible to charge the ink particles passing through the charging electrode 13. In order to charge each ink particle, the charging electrode 13 according to this embodiment is positioned near the breakpoint where the printing ink ejected from the nozzle 12 becomes a particle.

[0156] In detail, a pulse potential controllable by the controller 100 is applied to the charging electrode 13. When a relatively high voltage is applied to the charging electrode 13, the amount of charge (magnitude of negative charge) of each ink particle becomes larger compared to when a lower voltage is applied. When the amount of charge of each ink particle is large, it is deflected more by the deflection electrode 15 compared to when the charge is small. The amount of deflection of the ink particles can be controlled by adjusting the magnitude of the pulse potential of the controller 100. The ink particles charged by the charging electrode 13 reach the deflection electrode 15, which has passed to the side of the charge detection sensor 14.

[0157] Furthermore, the solvent discharged from the nozzle 12 passes to the side of the charge detection sensor 14 without being charged, and reaches the deflection electrode 15.

[0158] (Static charge detection sensor 14) As illustrated in Figure 3, the charge detection sensor 14 is positioned below the charging electrode 13. More specifically, the charge detection sensor 14 is positioned below the metal plate constituting the charging electrode 13 (the metal plate on the right side of the page in the example figure) so as not to intersect with the trajectory of the flying ink droplets. By positioning the charge detection sensor 14 in this way, it is possible to avoid collisions between the ink droplets and the charge detection sensor 14.

[0159] Furthermore, the charge detection sensor 14 according to this embodiment is connected to a circuit board provided inside the housing 10. The charge detection sensor 14 can detect the charge state of ink droplets passing to its side (in particular, the amount of charge of each ink droplet). The detection result from the charge detection sensor 14 is output to the control unit 101 as a detection signal. Based on this detection signal, the control unit 101 can determine whether each ink droplet is properly charged or not.

[0160] (Deflection electrode 15) As illustrated in Figure 3, the deflection electrode 15 is composed of a pair of electrically conductive metal plates (so-called "counter electrodes") and is positioned below the charging electrode 13 and the charge detection sensor 14. Here, the pair of metal plates are fixed to the housing 10 in a position where their respective longitudinal directions are aligned approximately vertically and they face each other horizontally. Ink particles that pass between the pair of metal plates constituting the charging electrode 13 will pass between the pair of metal plates constituting the deflection electrode 15.

[0161] A voltage controllable by the controller 100 (hereinafter also referred to as the "deflection voltage") is applied to the deflection electrode 15. This creates a potential difference between the pair of metal plates constituting the deflection electrode 15, corresponding to the deflection voltage. This potential difference allows the flight direction of the ink particles to be deflected according to the amount of charge each ink particle has. The flight direction of the ink particles can be deflected along the direction in which the pair of metal plates constituting the deflection electrode 15 are aligned.

[0162] In other words, the flight direction of the ink droplets can be controlled via the deflection voltage applied to the charging electrode 13 and the deflection electrode 15, respectively. The ink droplets whose flight direction is controlled in this way include those deflected by the deflection electrode 15 and those not deflected by the deflection electrode 15 (undeflected). Of these, the ink droplets deflected by the deflection electrode 15 are involved in printing on the object W. The ink droplets deflected by the deflection electrode 15 are ejected from the discharge port 10a provided on the lower surface of the housing 10 and land on the object W.

[0163] On the other hand, ink particles that are not deflected by the deflection electrode 15 do not participate in printing on the object W to be printed. These ink particles, or axial printing ink that is not atomized in the first place, reach the gutter 16, as illustrated by the dashed line in Figure 3. Similarly, solvents used to clean the nozzles 12, etc., in the print head 1 that have passed through the deflection electrode 15 also reach the gutter 16.

[0164] -Details of the deflection electrode 15- Specifically, the deflection electrode 15 according to this embodiment is composed of a first electrode plate 151 and a second electrode plate 152 facing the first electrode plate 151. The first electrode plate 151 is grounded. The first electrode plate 151 can also be called a ground electrode. A high voltage is applied to the second electrode plate 152.

[0165] The first electrode plate 151 faces the second electrode plate 152 with a gap between them. The first electrode plate 151 has a first opposing surface 151a. The first opposing surface 151a extends in the vertical direction and faces the second electrode plate 152.

[0166] On the other hand, the second electrode plate 152 has a second opposing surface 152a, an inclined surface 152b, and a bent surface 152c. The second opposing surface 152a and the inclined surface 152b are continuous in the vertical direction from the nozzle 12 side to the discharge port 10a side. The inclined surface 152b and the bent surface 152c are continuous in the vertical direction from the nozzle 12 side to the discharge port 10a side.

[0167] The second opposing surface 152a extends straight along the vertical direction. The second opposing surface 152a extends parallel to the first opposing surface 151a.

[0168] The inclined surface 152b is inclined in a direction away from the flight axis Ax as described above (see Figure 4A). More specifically, the inclined surface 152b extends from the tip on the discharge port 10a side of the second opposing surface 152a, and extends in a direction away from the flight axis Ax (to the left of the page in Figure 4A) as it goes from the upper side downwards in the vertical direction.

[0169] The bent surface 152c extends from the tip of the inclined surface 152b and is more steeply curved than the inclined surface 152b in a direction away from the flight axis Ax. More specifically, the bent surface 152c extends from the tip of the inclined surface 152b on the discharge port 10a side and extends more steeply than the bent surface 152c in a direction away from the flight axis Ax as it moves from the upper side downwards in the vertical direction.

[0170] More specifically, the extension line El extending from the tip of the bent surface 152c (particularly the tip on the discharge port 10a side) does not intersect with the discharge port 10a, but rather with the side wall portion 10s of the housing 10 around the discharge port 10a, as shown in Figure 4A.

[0171] (Gutter 16) As illustrated in Figure 3, the gutter 16 is composed of a curved tube with its opening 16a facing upward and is positioned below the deflection electrode 15. The gutter 16 according to this embodiment can recover printing ink that is not involved in printing on the object W to be printed, and solvent that has passed through the nozzle 12 (specifically, solvent discharged from the nozzle 12).

[0172] In this embodiment, the opening 16a of the gutter 16 and the opening end of the nozzle 12 are positioned facing each other, with the opening end of the nozzle 12 located directly above the opening 16a of the gutter 16. This arrangement makes it possible to receive fluid flowing vertically from the opening end of the nozzle 12, as well as fluid that has flown, through the opening 16a of the gutter 16.

[0173] The gutter 16 is equipped with an electric or thermistor-type gutter sensor 16b (see Figure 3). The gutter sensor 16b detects whether or not printing ink is present in the gutter 16. If printing ink is present in the gutter 16, it determines that the adjustment of the ink shaft is complete. If printing ink is not present in the gutter 16, it determines that the adjustment of the ink shaft is not complete. The gutter sensor 16b is connected to the control unit 101 of the controller 100 and is configured to output a signal to the control unit 101.

[0174] The printing ink or solvent recovered by the gutter 16 is sent back to the controller 100 via the connecting cable 1000, ink supply pipe 44, solvent supply pipe 54, etc., and stored in the ink tank 106.

[0175] (Cleaning nozzle 17) As illustrated in Figure 3, the cleaning nozzle 17 is located within the print head 1. The cleaning nozzle 17 functions as a so-called solvent spray unit. The cleaning nozzle 17 is a nozzle for cleaning the nozzle 12, charging electrode 13, deflection electrode 15, etc., in the print head 1 by discharging or spraying a solvent onto them, and is capable of spraying a solvent that can dissolve ink. The solvent sprayed from the cleaning nozzle 17 is supplied from a solvent supply unit 105, for example, a solvent cartridge 51.

[0176] In this embodiment, as illustrated by reference numeral L1 in Figure 4B, the solvent sprayed from the cleaning nozzle 17 is sprayed onto at least the nozzle 12. This allows the nozzle 12 to be cleaned. By cleaning the nozzle 12, the solvent can be smoothly discharged from the nozzle 12 during head cleaning.

[0177] (Shutter 21) The shutter 21 opens and closes the discharge port 10a. The shutter 21 is electrically connected to the control unit 101 and opens and closes in response to a control signal from the control unit 101. By closing the discharge port 10a with the shutter 21, leakage of solvent from the discharge port 10a can be suppressed, for example, during head cleaning. Alternatively, instead of closing the discharge port 10a with the shutter 21, the discharge port 10a may be closed with a cap or the like.

[0178] (Suction device 22) The suction unit 22 sucks air from the internal space of the print head 1, particularly from the flight space, and exhausts it to the external space of the print head 1. The suction unit 22 is electrically connected to the control unit 101 and operates in response to control signals from the control unit 101. When the suction unit 22 operates, it is possible to suck in and exhaust air from the internal space of the print head 1. The suction unit 22 is an example of the "suction unit" and "drying unit" in this embodiment.

[0179] (Filter 23) The filter 23 filters the air drawn in by the suction device 22. By filtering the air with the filter 23, solvents (especially volatile solvents) contained in the air, as well as odors inside the print head 1, can be removed.

[0180] (Posture sensor 24) The attitude sensor 24 detects the orientation of the print head 1. The attitude sensor 24 is, for example, an acceleration sensor or a gravity sensor. As shown in Figure 3, the attitude sensor 24 is attached to the print head 1. The attitude sensor 24 is electrically connected to the control unit 101 and inputs a detection signal to the control unit 101.

[0181] (Diffusion means 18) Figure 30 is a table illustrating the diffusion methods related to this disclosure.

[0182] As illustrated in Figure 3, the print head 1 further includes the aforementioned diffusion means 18. In this embodiment (first embodiment), this diffusion means 18, together with the air generation unit 108, constitutes a diffusion module 70.

[0183] The diffusion means 18 according to this disclosure diffuses the solvent (liquid) supplied to the print head 1 from the solvent supply unit 105, which serves as a liquid supply unit, and discharged or sprayed within the print head 1 during the aforementioned head cleaning.

[0184] The diffusion means 18 can clean the components inside the print head 1 by diffusing the solvent. The components to be cleaned include at least one of the gutter 16, the nozzle 12, and the deflection electrode 15.

[0185] Furthermore, the diffusion means 18 according to this disclosure diffuses the solvent (liquid) into the print head 1 by crossing the substance 200 with respect to the flight axis Ax of the solvent (liquid) discharged or sprayed within the print head 1.

[0186] Here, the "diffusion" in this disclosure includes at least "Type 1 diffusion," "Type 2 diffusion," and "Type 3 diffusion," as shown in Figure 30. Type 1 diffusion is diffusion using a fluid for substance 200, and using air for that fluid. Type 2 diffusion is diffusion using a fluid for substance 200, and using a solvent for that fluid. Type 3 diffusion is diffusion using a machine part for the solid substance 200. These names are merely convenient concepts for the sake of brevity in the explanation and do not prescribe any priority or order of each type of diffusion.

[0187] In other words, both Type 1 and Type 2 diffusion refer to the diffusion of a solvent (liquid) by having the diffusion means 18 intersect the fluid substance 200 with respect to the flight axis Ax of the solvent (liquid) discharged or sprayed within the print head 1.

[0188] For example, the diffusion means 18 according to this embodiment performs a first type of diffusion using air for the fluid. In this case, the diffusion means 18 diffuses the solvent by crossing the air with respect to the flight axis Ax of the solvent discharged or sprayed in the print head 1.

[0189] The configuration for the first type of diffusion is illustrated in this embodiment (first embodiment), and in the second and third embodiments described later, as shown in Figure 30. The configuration for the second type of diffusion is illustrated in the fourth modified form. The configuration for the third type of diffusion is illustrated in the fifth and sixth embodiments.

[0190] The first and second types of diffusion are closely related to the solvent flow path from the solvent supply unit 105 to the print head 1. Therefore, before describing the diffusion means 18 in detail, the configuration of the ink and solvent flow paths in the inkjet recording device I, specifically the configuration of the ink supply pipe 44 and the solvent supply pipe 54, will be described with reference to Figure 5.

[0191] <Distribution channels for inks and solvents> As described above, the ink supply pipe 44 supplies ink from the ink cartridge 41 to the ink tank 106, and also supplies printing ink from the ink tank 106 to the print head 1 via the connecting cable 1000. On the other hand, the solvent supply pipe 54 supplies solvent from the solvent cartridge 51 to the ink tank 106, or to the print head 1 via the connecting cable 1000.

[0192] -First Route R1- The ink supply pipe 44 constitutes, for example, a path (first path R1) for supplying ink (ink before density adjustment) from the ink cartridge 41 to the ink tank 106.

[0193] As shown in Figure 5, the first path R1 in this embodiment is composed of a first ink tube 44a, a second ink tube 44b, and a third ink tube 44c, which serve as ink flow tubes. In this embodiment, the first ink tube 44a, the second ink tube 44b, and the third ink tube 44c are all located within the controller 100.

[0194] The first ink tube 44a has one end connected to the hollow ink needle 43 and the other end branching to the second ink tube 44b and the third ink tube 44c (see branching point B1 in Figure 5). As an ink flow tube, the first ink tube 44a connects the hollow ink needle 43 and the ink tank 106 via the second ink tube 44b and the third ink tube 44c, and flows ink from the hollow ink needle 43 to the ink tank 106. In this embodiment, ink is introduced to the ink tank 106 via the third ink tube 44c, but it may also be introduced via, for example, the second ink tube 44b. In this case, the ink is introduced to the ink tank 106 without passing through the viscometer 46.

[0195] It should be noted that the classification of the first ink tube 44a, the second ink tube 44b, and the third ink tube 44c is merely for convenience. For example, the first ink tube 44a and the second ink tube 44b may be considered as a single ink flow tube. In that case, the ink flow tube composed of the first ink tube 44a and the second ink tube 44b would be directly connected to the hollow ink needle 43 and the ink tank 106.

[0196] Furthermore, a first pump P1 is positioned in the middle of the first ink tube 44a. This first pump P1 is a suction pump that creates a flow from the hollow needle 43 for ink towards the first ink tube 44a.

[0197] Furthermore, a confluence section 45 is provided in the first ink tube 44a between the hollow needle 43 for the ink and the first pump P1. This confluence section 45 is configured to combine the solvent or ink in the first ink tube 44a. In particular, the confluence section 45 illustrated in Figure 5 is connected to the third solvent tube 54c of the solvent supply tube 54 and is configured to combine the solvent with the ink flowing through the first ink tube 44a. The ink combined in the first ink tube 44a may be printing ink.

[0198] Furthermore, an eighth valve V8 is located in the first ink tube 44a between the confluence section 45 and the first pump P1. This eighth valve V8 is an on / off valve that opens and closes the flow path of the first ink tube 44a.

[0199] The second ink tube 44b connects the other end (branch section B1) of the first ink tube 44a to the ink tank 106. A first valve V1 is located in the middle of the second ink tube 44b. This first valve V1 is an on / off valve that opens and closes the flow path of the second ink tube 44b.

[0200] The third ink tube 44c connects the other end (branch section B1) of the first ink tube 44a to the ink tank 106. An eleventh valve V11 is located in the middle of the third ink tube 44c. This eleventh valve V11 is an on / off valve that opens and closes the flow path of the third ink tube 44c.

[0201] Furthermore, a viscometer 46 is positioned in the third ink tube 44c between the 11th valve V11 and the ink tank 106. This viscometer 46 detects the flow rate of ink or printing ink flowing through the third ink tube 44c and measures the viscosity based on that flow rate. The viscometer 46 inputs a detection signal corresponding to the measurement result to the control unit 101. In this embodiment, a viscometer 46 based on the principle of detecting ink flow rate is used, but the present invention is not limited to this, and for example, a viscometer 46 that repeatedly fills and discharges ink and measures the viscosity based on the time of ink discharge may be used.

[0202] Ink from the ink cartridge 41 is supplied to the ink tank 106 by passing sequentially through the hollow ink needle 43, ink reservoir 42, first ink tube 44a, second ink tube 44b, and third ink tube 44c, based on the operating status of the first pump P1 and the open / closed status of the first valve V1, fifth valve V5, and eighth valve V8.

[0203] -Second route R2- On the other hand, the solvent supply pipe 54, together with some elements of the ink supply pipe 44, constitutes a path (second path R2) for supplying solvent from the solvent cartridge 51 to the ink tank 106.

[0204] As shown in Figure 5, the second path R2 according to this embodiment is composed of the first solvent pipe 54a of the solvent supply pipe 54, a part of the first ink pipe 44a (the part from the connection part B2 to the branching part B1 in Figure 5), and the entirety of the second ink pipe 44b and the third ink pipe 44c. In this embodiment, the first solvent pipe 54a is located inside the controller 100.

[0205] As mentioned above, the names "ink supply pipe 44" and "solvent supply pipe 54" are merely for convenience, based on a view of a part of each flow pipe. The first ink pipe 44a, second ink pipe 44b, and third ink pipe 44c may serve both ink and solvent distribution purposes. Each flow pipe may contribute to the configuration of one or more pathways.

[0206] The first solvent pipe 54a has one end connected to the hollow needle 43 for ink and the other end (connection part B2) connected to the first ink pipe 44a. A 13th valve V13 is located in the middle of the first solvent pipe 54a in the solvent supply pipe 54. This 13th valve V13 is an on / off valve that opens and closes the flow path of the first solvent pipe 54a.

[0207] The solvent from the solvent cartridge 51 is supplied to a mid-section of the first ink tube 44a (see connection point B2 in Figure 5) by sequentially passing through the solvent hollow needle 53, solvent reservoir 52, and first solvent tube 54a, depending on the operating status of the first pump P1 and the opening / closing status of the 13th valve V13. The solvent supplied to this section is then supplied to the ink tank 106 by sequentially passing through the first ink tube 44a, second ink tube 44b, and third ink tube 44c, depending on the opening / closing status of the first valve V1 and the 11th valve V11.

[0208] The ink supplied through the first pathway R1 is concentrated by the solvent supplied through the second pathway R2. As a result, printing ink is stored in the ink tank 106.

[0209] -Third Route R3- Returning to the explanation regarding the ink supply pipe 44, this ink supply pipe 44 also constitutes a path (third path R3) for circulating and stirring the contents (printing ink) of the ink tank 106 within the controller 100.

[0210] As shown in Figure 5, the third path R3 in this embodiment is composed of the fourth ink tube 44d and the fifth ink tube 44e of the ink supply pipe 44, a part of the first ink tube 44a (the part from the connection part B2 to the branching part B1 in Figure 5), and the entirety of the second ink tube 44b and the third ink tube 44c. In this embodiment, both the fourth ink tube 44d and the fifth ink tube 44e are located inside the controller 100.

[0211] The fourth ink tube 44d has one end connected to the ink tank 106 and the other end (connection part B2) connected to the first ink tube 44a. A ninth valve V9 is located in the middle of the fourth ink tube 44d. This ninth valve V9 is an on / off valve that opens and closes the flow path of the fourth ink tube 44d.

[0212] The fifth ink tube 44e has one end connected to the ink tank 106 and the other end (connection part B2) connected to the first ink tube 44a. A fifth valve V5 is located in the middle of the fifth ink tube 44e. This fifth valve V5 is an on / off valve that opens and closes the flow path of the fifth ink tube 44e.

[0213] Furthermore, the connection position between the fourth ink tube 44d and the ink tank 106 (the position where the fourth ink tube 44d draws printing ink) is positioned higher in the height direction of the ink tank 106 than the connection position between the fifth ink tube 44e and the ink tank 106 (the position where the fifth ink tube 44e draws printing ink).

[0214] The printing ink in the ink tank 106 is drawn out by the fourth ink tube 44d or the fifth ink tube 44e based on the operating status of the first pump P1 and the opening and closing status of the first valve V1, fifth valve V5, ninth valve V9, and eleventh valve V11. It then passes sequentially through a portion of the first ink tube 44a (the portion from connection point B2 to branch point B1 in Figure 5), the second ink tube 44b, and the third ink tube 44c before being sent back to the ink tank 106. This causes the printing ink to circulate within the controller 100.

[0215] Furthermore, by configuring the system to not only circulate the ink within the controller 100 but also to draw the printing ink from two locations at different heights, the printing ink can be agitated within the ink tank 106. This allows the printing ink to remain in a liquid state. This configuration is particularly effective when using pigment ink.

[0216] -Fourth Route R4- The ink supply pipe 44 further constitutes a path (fourth path R4) for supplying printing ink from the ink tank 106 to the nozzle 12 and for supplying printing ink back to the ink tank 106 from the gutter 16. This fourth path R4 is composed of the ink supply pipe 44 and the ink tube 1001 of the connecting cable 1000.

[0217] As shown in Figure 5, the fourth path R4 according to this embodiment consists of the ink tube 1001 and the sixth ink tube 44f and the seventh ink tube 44g of the ink supply pipe 44. Both the sixth ink tube 44f and the seventh ink tube 44g, together with the ink tube 1001, are connected to the controller 100 and the print head 1.

[0218] The sixth ink tube 44f has one end connected to the ink tank 106 and the other end connected to the nozzle 12 via the ink tube 1001. A third pump P3 is positioned in the middle of the sixth ink tube 44f. This third pump P3 is a suction pump that draws in ink to create a flow from the ink tank 106 toward the sixth ink tube 44f.

[0219] Furthermore, a 14th valve V14 is located in the 6th ink tube 44f between the 3rd pump P3 and the nozzle 12. This 14th valve V14 is an on / off valve that opens and closes the flow path of the 6th ink tube 44f.

[0220] The seventh ink tube 44g has one end connected to the gutter 16 via the ink tube 1001 and the other end connected to the ink tank 106. A fourth pump P4 is positioned in the middle of the seventh ink tube 44g. This fourth pump P4 is a suction pump that creates a flow from the gutter 16 towards the seventh ink tube 44g.

[0221] Furthermore, the 10th valve V10 is located in the 7th ink tube 44g between the gutter 16 and the 4th pump P4. This 10th valve V10 is an on / off valve that opens and closes the flow path of the 7th ink tube 44g.

[0222] The printing ink in the ink tank 106 is drawn out by the sixth ink tube 44f according to the operating status of the third pump P3 and the opening / closing status of the 14th valve V14, and discharged from the nozzle 12. The printing ink discharged from the nozzle 12 lands on the surface of the object to be printed W when printing is in progress, and is collected by the gutter 16 when not printing. The latter printing ink is drawn out by the seventh ink tube 44g according to the operating status of the fourth pump P4 and the opening / closing status of the 10th valve V10, and sent back to the ink tank 106. This causes the printing ink to circulate between the controller 100 and the print head 1.

[0223] -Route 5 R5- Meanwhile, the solvent supply pipe 54, together with some elements of the ink supply pipe 44, constitutes a path (fifth path R5) for supplying cleaning solvent from the solvent cartridge 51 to the nozzle 12. This fifth path R5 is composed of the ink supply pipe 44 and the solvent tube 1002 of the connecting cable 1000.

[0224] As shown in Figure 5, the fifth path R5 according to this embodiment is composed of a solvent tube 1002, a part of the first solvent tube 54a (the upstream end including the connection to the hollow solvent needle 53) and a second solvent tube 54b in the solvent supply pipe 54, and a part of the sixth ink tube 44f (the downstream end including the connection to the nozzle 12). The second solvent tube 54b, together with the solvent tube 1002, connects the controller 100 and the print head 1.

[0225] The second solvent pipe 54b has one end connected to the first solvent pipe 54a between the solvent hollow needle 53 and the 13th valve V13, and the other end connected to the 6th ink pipe 44f between the 14th valve V14 and the nozzle 12 via the solvent tube 1002. A second pump P2 is located in the middle of the second solvent pipe 54b in the solvent supply pipe 54. This second pump P2 is a suction pump for drawing in fluid from the solvent hollow needle 53 toward the solvent supply pipe 54 (particularly the second solvent pipe 54b).

[0226] Furthermore, a 12th valve V12 is located in the second solvent pipe 54b between the second pump P2 and the nozzle 12. This 12th valve V12 is an on / off valve that opens and closes the flow path of the second solvent pipe 54b in the solvent supply pipe 54.

[0227] The solvent from the solvent cartridge 51 passes sequentially through the solvent hollow needle 53, solvent reservoir 52, first solvent pipe 54a, and second solvent pipe 54b, depending on the operation status of the second pump P2 and the opening / closing status of the 12th valve V12, and is supplied to an intermediate part of the 6th ink pipe 44f (the part between the 14th valve V14 and the nozzle 12). The solvent supplied to this part is discharged from the nozzle 12. This solvent cleans the print head 1.

[0228] A cleaning nozzle 17 is connected to the second solvent pipe 54b. As described above, the cleaning nozzle 17 can discharge or spray a solvent as a cleaning liquid. A 15th valve V15 is provided between the cleaning nozzle 17 and the second solvent pipe 54b to control the supply of solvent to the cleaning nozzle 17.

[0229] -Route 6 R6- The solvent supply pipe 54 further constitutes a path (sixth path R6) for supplying solvent from the solvent cartridge 51 to the ink supply pipe 44 and the hollow ink needle 43 via the confluence section 45.

[0230] As shown in Figure 5, the sixth path R6 according to this embodiment is composed of a part of the first solvent pipe 54a, a part of the second solvent pipe 54b, and a third solvent pipe 54c in the solvent supply pipe 54. Here, "a part of the first solvent pipe 54a" refers to the portion from the hollow solvent needle 53 to the connection point B3 between the first solvent pipe 54a and the second solvent pipe 54b. Here, "a part of the second solvent pipe 54b" refers to the portion from the connection point B3 between the first solvent pipe 54a and the second solvent pipe 54b to the position between the second pump P2 and the 12th valve V12 (see connection point B4 in Figure 5). The sixth path R6 branches off from the fifth path R5 downstream of the second pump P2. In this embodiment, the third solvent pipe 54c is located inside the controller 100.

[0231] The third solvent pipe 54c has one end connected to the second solvent pipe 54b between the second pump P2 and the 12th valve V12, and the other end connected to the junction 45.

[0232] The third solvent pipe 54c, together with the aforementioned portion of the first solvent pipe 54a and the aforementioned portion of the second solvent pipe 54b, constitutes the "solvent flow pipe" in this embodiment. When the solvent reservoir 52 receives the solvent cartridge 51, the third solvent pipe 54c allows the solvent in the solvent cartridge 51 to flow through the first solvent pipe 54a and the second solvent pipe 54b to the confluence section 45.

[0233] Here, the aforementioned second pump P2 is positioned in the middle of the second solvent pipe 54b that constitutes the solvent flow pipe. This second pump P2 can also be considered as a solvent pump that operates to generate a flow from the second solvent pipe 54b towards the hollow needle 43 for ink via the confluence section 45 and the first ink pipe 44a.

[0234] Furthermore, a 18th valve V18 is located in the second solvent pipe 54b between the confluence section 45 and the second pump P2. This 18th valve V18 is a second on-off valve that opens and closes the flow path of the second solvent pipe 54b.

[0235] -Pathways related to ink suction- The controller 100 also has a path related to ink suction. For example, the controller 100 has a suction path 47 connected to the nozzle 12. A sixth valve V6 is provided in the suction path 47. For example, when not printing, by operating the first pump P1 with this sixth valve V6 open, ink can be drawn in through the suction path 47 and sent back to the controller 100.

[0236] <Diffusion Module 70> Figure 6 is a diagram illustrating the overall configuration of the diffusion module 70. Figure 7 is a perspective view illustrating the internal configuration of the print head 1.

[0237] As already explained, the diffusion module 3A according to this embodiment consists of an air generation unit 108 housed in the controller 100 and a diffusion means 18 of the print head 1.

[0238] As described with reference to Figure 30, the diffusion means 18 according to this embodiment performs a first type of diffusion of the substance 200 using a fluid. To perform the first type of diffusion, the diffusion means 18 has a fluid injection unit 18c that injects a fluid as the substance 200 into the print head 1. This fluid injection unit 18c is composed of a fluid injection unit 18c that injects air as the fluid.

[0239] In this embodiment, air is discharged from the fluid injection unit 18c, but the present invention is not limited to this. For example, a separate drying air outlet may be provided that generates air with a higher airflow rate and lower pressure than the air discharged from the fluid injection unit 18c and injects it. In this case, the drying time can be shortened by switching the use of the drying air outlet with a solenoid valve.

[0240] Meanwhile, the air generation unit 108 supplies the fluid used by the diffusion means 18 to the diffusion means 18. In this embodiment, the air generation unit 108 generates air as a fluid and supplies it to the diffusion means 18.

[0241] (Air generating unit 108) The air generation unit 108 generates air that is injected from the fluid injection unit 18c of the diffusion means 18. The air generation unit 108 supplies the generated air to the diffusion means 18 of the print head 1. The air generation unit 108 is an example of the "air generation unit" in this embodiment.

[0242] The air generating unit 108 is used when the diffusion means 18 performs type 1 diffusion. When the diffusion means 18 performs type 2 or type 3 diffusion, the air generating unit 108 is not essential.

[0243] The air generated by the air generation unit 108 and injected from the fluid injection unit 18c may be, for example, high-pressure air. More specifically, high-pressure air is air with a pressure of 100 kPa or more and 300 kPa, and more specifically, air with a pressure of 150 kPa or more and 250 kPa or less. As an example, the fluid injection unit 18c according to this embodiment is configured to inject high-pressure air of slightly less than 200 kPa.

[0244] Furthermore, the air generation unit 108 may also generate so-called dry air. For example, in this embodiment, the air generation unit 108 generates dry air, and the fluid injection unit 18c is configured to pressurize and inject the dry air.

[0245] Specifically, as shown in Figure 5, the air generation unit 108 according to this embodiment includes a first fluid conduit 108a, an air filter 108b, an air pump 108c, a cooler 108d, a water separator 108e, a first pressure gauge 108f, an air dryer 108g, a second pressure gauge 108h, and a flow meter 108i.

[0246] The first fluid conduit 108a is a path through which air flows. The first fluid conduit 108a is equipped with, in order from upstream, an air filter 108b, an air pump 108c, a cooler 108d, a water separator 108e, a first pressure gauge 108f, an air dryer 108g, a second pressure gauge 108h, and a flow meter 108i.

[0247] The upstream end of the first fluid conduit 108a is connected to air tanks located inside and outside the controller 100. The downstream end of the first fluid conduit 108a is connected to the diffusion means 18 via an umbilical cable 71. The umbilical cable 71, along with the other conduits, is bundled with the connecting cable 1000.

[0248] The air filter 108b is a filter that removes foreign matter from the air. The air that has passed through the air filter 108b then proceeds to the air pump 108c.

[0249] The air pump 108c is a diaphragm-type air pump, for example, built into the controller 100. The air pump 108c draws in air that has passed through the air filter 108b and sends it to the print head 1 via the cooler 108d, water separator 108e, etc. The air pump 108c is electrically connected to the control unit 101 and operates by receiving control signals from the control unit 101.

[0250] The cooler 108d cools the air whose temperature has risen due to the suction of the air pump 108c. The water separator 108e separates the water produced by condensation caused by the suction of the air pump 108c from the air. The cooler 108d is electrically connected to the control unit 101 and operates by receiving control signals from the control unit 101.

[0251] The air dryer 108g is, for example, a hollow fiber membrane type air dryer built into the controller 100. The air dryer 108g generates dry air by drying the air after it passes through the water separator 108e. By incorporating the air dryer 108g into the controller 100, the printing head 1 can be made more compact.

[0252] The first pressure gauge 108f is disposed at a position between the water separator 108e and the air dryer 108g in the first fluid pipeline 108a. The first pressure gauge 108f detects the pressure of the air at that position. The first pressure gauge 108f is electrically connected to the control unit 101 and inputs a detection signal to the control unit 101. Based on the detection signal of the first pressure gauge 108f, the control unit 101 determines the blockage or narrowing of the first fluid pipeline 108a upstream of the air dryer 108g.

[0253] The second pressure gauge 108h is disposed at a position downstream of the air dryer 108g in the first fluid pipeline 108a. The second pressure gauge 108h detects the pressure of the air at that position. The second pressure gauge 108h is electrically connected to the control unit 101 and inputs a detection signal to the control unit 101. Based on the detection signal of the second pressure gauge 108h, the control unit 101 determines the blockage or narrowing of the first fluid pipeline 108a, the umbilical cable 71, the air path (second fluid pipeline 18a) of the diffusion means 18, and the fluid injection part 18c, etc., downstream of the air dryer 108g.

[0254] The second pressure gauge 108h is disposed on the way from the air dryer 108g to the diffusion means 18, and exemplifies the "pressure sensor" in the present embodiment in that it can detect the blockage of air.

[0255] In addition, the first pressure gauge 108f and the second pressure gauge 108h can also be used to determine the pressure of the air when the pressure of the air ejected from the diffusion means 18 increases.

[0256] The flowmeter 108i is disposed at a position between the second pressure gauge 108h in the first fluid pipeline 108a and the upstream end of the umbilical cable 71. The flowmeter 108i detects the air flow rate (air flow) at this position. The flowmeter 108i is electrically connected to the control unit 101 and inputs a detection signal to the control unit 101. The control unit 101 controls the ejection of air from the fluid ejection unit 118c based on the detection signal of the flowmeter 108i.

[0257] (Diffusion means 18) The diffusion means 18 ejects the dry air generated by the air generation unit 108. The diffusion means 18 according to the present embodiment is configured to be suitable for implementing the first type of diffusion. The same applies to the second embodiment described later. When implementing the first type of diffusion, the configuration and structure of the diffusion means 18 will be changed as in the second and third modification examples described later.

[0258] Specifically, as shown in FIG. 5, the diffusion means 18 according to the present embodiment includes a second fluid pipeline 18a, a fluid control valve 18b, and a fluid ejection unit 18c. The fluid control valve 18b according to the present embodiment corresponds to the "second valve V22" in FIG. 5.

[0259] The second fluid pipeline 18a is a path through which the fluid (air) supplied from the air generation unit 108 flows. In the second fluid pipeline 18a, the fluid control valve 18b and the fluid ejection unit 18c are arranged in order from the upstream side.

[0260] The upstream end of the second fluid pipeline 18a is connected to the downstream end of the umbilical cable 71. The dry air generated by the air generation unit 108 flows into the second fluid pipeline 18a through the umbilical cable 71.

[0261] The fluid control valve 18b is a control valve for controlling the injection of air generated by the air generation unit 108. The fluid control valve 18b is composed of a solenoid valve electrically connected to the control unit 101. The fluid control valve 18b operates in response to a control signal from the control unit 101. When the fluid control valve 18b operates, the second fluid pipeline 18a, particularly the second fluid pipeline 18a upstream of the fluid injection unit 18c, is opened and closed.

[0262] The fluid injection unit 18c injects a fluid, which is the substance 200, into the print head 1. More specifically, the fluid injection unit 18c according to this embodiment injects air, which is the fluid, into the print head 1.

[0263] For example, as shown in Figure 6, the fluid injection unit 18c according to this embodiment is an air nozzle that injects dry air generated by the air generation unit 108. The fluid injection unit 18c, as an air nozzle, has an openable and closable orifice 18d. This orifice 18d is electrically connected to the control unit 101 and opens and closes in response to a control signal from the control unit 101.

[0264] Furthermore, the fluid injection unit 18c according to this embodiment is configured to inject air toward the deflection electrode 15 and to interpose the aforementioned flight axis Ax between it and the deflection electrode 15.

[0265] More specifically, as shown in Figures 4A, 4B, and 7, the fluid injection unit 18c according to this embodiment is positioned on the first electrode plate 151 to inject air toward the second electrode plate 152. The fluid injection unit 18c is embedded within the first electrode plate 151 and opens toward the first opposing surface 151a. The opening of the fluid injection unit 18c faces toward the second electrode plate 152.

[0266] More specifically, the air injection axis Aa in the fluid injection section 18c extends toward the second electrode plate 152 of the deflection electrode 15, as illustrated in Figure 4A. In other words, the air injection axis Aa intersects with the second electrode plate 152, as illustrated in Figure 4A. This injection axis Aa may intersect with the second opposing surface 152a, as shown in the example, or it may intersect with the inclined surface 152b, as shown in the example.

[0267] In this context, "air injection axis Aa" refers to the central axis of the air injected from the fluid injection unit 18c. That is, the fact that the air injection axis Aa extends toward the second electrode plate 152 indicates that the fluid injection unit 18c in this embodiment injects air toward the deflection electrode 15, particularly toward the second electrode plate 152.

[0268] More specifically, the air injection axis Aa in the fluid injection unit 18c intersects with the flight axis Ax, as illustrated in Figure 4A. In other words, in this embodiment, the fluid injection unit 18c is positioned such that the flight axis Ax of the solvent ejected from the nozzle 12 is interposed between the fluid injection unit 18c and the deflection electrode 15, particularly the second electrode plate 152.

[0269] During head cleaning, the control unit 101 operates the air pump 108c with the fluid control valve 18b or orifice 18d closed. This allows the drying air to be pressurized. By opening the fluid control valve 18b or orifice 18d while the drying air is pressurized, the drying air is injected from the fluid injection unit 18c.

[0270] Here, as illustrated by reference numeral M1 in Figure 4B, the diffusion means 18 intersects the substance 200 or air as a fluid with respect to the flight axis Ax of the solvent discharged or sprayed within the print head 1. By intersecting the air with respect to the flight axis Ax, the diffusion means 18 diffuses the solvent within the print head 1.

[0271] Specifically, in the examples shown in Figures 4A and 4B, the flight axis Ax of the solvent discharged or ejected from the nozzle 12 is interposed between the fluid injection unit 18c and the second electrode plate 152, and the flight axis Ax intersects with the air injection axis Aa.

[0272] Therefore, as shown by reference numeral M1 in Figure 4B, the diffusion means 18 according to this embodiment can apply dry air ejected along the injection axis Aa to an axial solvent ejected from the nozzle 12 along the flight axis Ax, or to a droplet-shaped solvent ejected from the nozzle 12.

[0273] Furthermore, the diffusion means 18 according to this embodiment atomizes the solvent as shown by reference numeral M1 in Figure 4B by directing the air (dry air) sprayed from the fluid injection unit 18c onto the liquid (solvent) supplied from the solvent supply unit 105, which acts as a liquid supply unit.

[0274] The misting of the solvent is achieved, for example, by increasing the pressure of the air. The high-pressure air then strikes the solvent ejected along the flight axis Ax and collides with the second electrode plate 152. By making the air collide with the second electrode plate 152, dirt adhering to the second electrode plate 152 becomes easier to remove. Furthermore, by misting the solvent, the area of ​​the component that can be cleaned by the solvent is expanded compared to when the solvent is not misted.

[0275] By applying the solvent, which has been atomized by collision with dry air, to the second electrode plate 152, the second electrode plate 152 and other components within the print head 1 can be cleaned. This cleaning is particularly effective against, for example, ink-related stains.

[0276] As a functional element for controlling head cleaning by the solvent supply unit 105 and the diffusion means 18, the control unit 101 has a cleaning control unit 101a. The cleaning control unit 101a is an example of a "cleaning management unit" in this embodiment.

[0277] By the control performed by the cleaning control unit 101a, the diffusion means 18 adjusts at least one of the timing of discharging or injecting the solvent as a liquid in the printing head 1 and the timing of crossing the substance 200 with respect to the flight axis Ax. By this adjustment, the diffusion means 18 crosses the substance 200 with respect to the flight axis Ax.

[0278] Specifically, by the control performed by the cleaning control unit 101a, the diffusion means 18 adjusts both the timing of discharging or injecting the solvent as a liquid in the printing head 1 and the timing of crossing the substance 200 with respect to the flight axis Ax. By this adjustment, the diffusion means 18 crosses the substance 200 with respect to the flight axis Ax.

[0279] Here, the cleaning control unit 101a can control the timing of discharging or injecting the solvent in the printing head 1 through the opening timing of the 12th valve V12 as a solvent control valve. The cleaning control unit 101a can also adjust the timing of crossing the substance 200 with respect to the flight axis Ax through the opening timing of the fluid control valve 18b.

[0280] Also, the cleaning control unit 101a as a cleaning management unit manages the amount of solvent used during head cleaning so that an amount of solvent corresponding to the fluid (for example, air) ejected from the fluid ejection unit 18c is supplied.

[0281] Specifically, the cleaning control unit 101a as a cleaning management unit manages the amount of solvent used during head cleaning so that an amount of solvent corresponding to the air ejected from the fluid ejection unit 18c is supplied and leakage of the solvent from the discharge port 10a is suppressed. Details of the processing regarding the amount of solvent used will be described later. Note that the processing regarding the amount of solvent used in the cleaning control unit 101a is also applicable in various modifications described later.

[0282] Furthermore, the cleaning control unit 101a can change the head cleaning sequence based on the detection signal from the attitude sensor 24. The sequence can be changed, for example, by adjusting the amount of solvent supplied from the solvent supply unit 105. This suppresses solvent leakage from the print head 1, particularly from its housing 10.

[0283] Furthermore, the cleaning control unit 101a operates the shutter 21 to close the discharge port 10a when assisting the diffusion means 18. This suppresses solvent leakage from the print head 1, particularly from its housing 10.

[0284] Furthermore, when the discharge port 10a is closed by the shutter 21 during assistance, the cleaning control unit 101a activates the suction device 22 to draw air from inside the print head 1 and exhaust it. This dries the inside of the print head 1 and causes any solvent adhering to the inside of the print head 1 to volatilize. This suppresses solvent leakage from the print head 1, especially from its housing 10.

[0285] The following describes in detail the processing performed by the control unit 101 in this embodiment.

[0286] <Specific example of processing> (Determining whether head cleaning is necessary) Figures 8 and 9 are flowcharts illustrating the process for determining whether or not head cleaning is necessary. The processes shown in Figures 8 and 9 are performed by the control unit 101, for example, when the inkjet recording device I recovers from an error state (error recovery) and when a head cleaning execution instruction is input via the operation display unit 103. In addition, in the processes shown in Figures 8 and 9, the orifice 18d may be opened or closed instead of, or in addition to, the fluid control valve 18b.

[0287] First, in step SB1, the cleaning control unit 101a determines whether the inkjet recording device I is in a printable state. A printable state means that the inkjet recording device I is powered on and ink is circulating inside the inkjet recording device I. The determination in step SB1 can be made, for example, based on the detection signal from the gutter sensor 16b.

[0288] If the determination in step SB1 is YES, the cleaning control unit 101a proceeds to step SB2 of the control process. On the other hand, if the determination in step SB1 is NO, the cleaning control unit 101a proceeds to step SB3 of the control process.

[0289] In step SB2, the cleaning control unit 101a stops the ink circulation by stopping the ink supply from the controller 100 to the print head 1. This also stops the ejection of ink from the nozzle 12. This process is performed, for example, by closing the 14th valve V14 in Figure 5.

[0290] In step SB3, the cleaning control unit 101a supplies solvent from the controller 100 to the print head 1, thereby instructing the nozzle 12 to eject (spray) the solvent. The process in step SB3 is performed, for example, by opening the 12th valve V12 shown in Figures 5 and 6, and activating the second pump P2, which acts as a solvent pump in the same figures.

[0291] If nozzle 12 is functioning correctly, the solvent ejected from nozzle 12 by step SB3 is recovered by gutter 16. On the other hand, if nozzle 12 is malfunctioning (for example, if nozzle 12 is clogged with ink), the solvent ejected from nozzle 12 by step SB3 is not recovered by gutter 16.

[0292] Therefore, in step SB4, which follows step SB3, the cleaning control unit 101a determines whether or not the solvent ejected in step SB3 has passed through the gutter 16. The determination in step SB3 can be made, for example, based on the detection signal from the gutter sensor 16b.

[0293] If the determination in step SB4 is YES, the cleaning control unit 101a proceeds to step SB9 of the control process. On the other hand, if the determination in step SB4 is NO, the cleaning control unit 101a proceeds to step SB5 of the control process.

[0294] In step SB5, the cleaning control unit 101a performs a recovery operation for the nozzle 12. In this recovery operation, the cleaning control unit 101a sprays solvent from the cleaning nozzle 17. This process is performed, for example, by opening the 15th valve V15 in Figure 5. As explained with reference to the reference numeral L1 in Figure 4B, the solvent sprayed from the cleaning nozzle 17 is blown onto at least the nozzle 12. The nozzle 12 is cleaned by the solvent sprayed onto it. During the recovery operation, the 22nd valve V22 in Figure 5 is temporarily closed.

[0295] Furthermore, in the subsequent step SB6, the cleaning control unit 101a counts up the number of attempts at the recovery operation. The count of attempts is reset to zero each time the flow shown in Figure 8 is started. For example, at the time of the initial determination in step SB4, the number of attempts is zero.

[0296] In the subsequent step SB7, the cleaning control unit 101a determines whether the number of trials counted in step SB6 exceeds a predetermined threshold (N). The threshold N for the number of trials is stored in the controller 100 beforehand. This threshold N value can be set in advance by loading a configuration file or changed by user operation.

[0297] If the determination in step SB7 is NO, the cleaning control unit 101a returns the control process to step SB3. In step SB3, the cleaning control unit 101a instructs the solvent to be ejected again. If the abnormality of the nozzle 12 has been resolved by the recovery operation in step SB5, the determination in the subsequent step SB4 will be YES. On the other hand, if the determination in step SB7 is YES, the cleaning control unit 101a proceeds the control process to step SB8 in Figure 9.

[0298] In other words, the cleaning control unit 101a repeatedly performs the recovery operation of step SB5 until the determination of step SB4 is YES, that is, until the solvent passes through the gutter 16.

[0299] If the number of attempts to recover the nozzle 12 reaches N without the abnormality being resolved, the cleaning control unit 101a proceeds to step SB8 of the control process. On the other hand, if the abnormality of the nozzle 12 is resolved before the number of attempts to recover the nozzle 12 reaches N, the cleaning control unit 101a proceeds to step SB9 of the control process.

[0300] If the process proceeds to step SB8 as in the former case, the cleaning control unit 101a determines that the head cleaning cannot be performed normally and makes an "error determination." To eliminate the cause of the error, it displays instructions for cleaning the components of the print head 1 and controller 100 on the operation display unit 103.

[0301] For example, if the process proceeds from the determination in step SB7 to step SB8, there is concern about abnormalities in the components of the print head 1, such as the nozzle 12, gutter 16, and cleaning nozzle 17. In this case, the cleaning control unit 101a instructs the user via the operation display unit 103 to check the inside of the print head 1.

[0302] Meanwhile, in step SB9, the cleaning control unit 101a stops the discharge of solvent from the nozzle 12. The process in step SB9 is performed, for example, by closing the 12th valve V12 shown in Figures 5 and 6.

[0303] By performing steps SB3, SB4, and SB9 consecutively, the solvent is filled up to the solvent supply pipe 54 upstream of the 12th valve V12, while the solvent is discharged from the solvent supply pipe 54 downstream of the 12th valve V12. This controls the amount of solvent used during head cleaning. In other words, it becomes possible to use a constant amount of solvent as much as possible during head cleaning. This suppresses solvent leakage from the discharge port 10a during head cleaning.

[0304] The time interval between the completion of step SB3 and the start of step SB9 following step SB4 may be set to, for example, a range of 50 msec to 150 msec.

[0305] In the following step SB10, the cleaning control unit 101a activates the air pump 108c (air pump: ON). In the subsequent step SB11, the cleaning control unit 101a closes the fluid control valve 18b (solenoid valve: open → closed) and reads the pressure of the air generated by the air generation unit 108. The air pressure read here can be, for example, the detected pressure of the first pressure gauge 108f.

[0306] In the subsequent step SB12, the cleaning control unit 101a determines whether the aforementioned air pressure is normal based on the information read in step SB11. This determination can be made based on whether the detected air pressure exceeds a predetermined reference value.

[0307] If the determination in step SB12 is YES, the cleaning control unit 101a proceeds to step SB14 in Figure 9. On the other hand, if the determination in step SB12 is NO, the cleaning control unit 101a proceeds to step SB8 in Figure 9. The processing in step SB8 is as described above.

[0308] For example, if the process proceeds from the determination in step SB16 to step SB8, there is concern about an abnormality related to the diffusion module 70, such as clogging of the air filter 108b. In this case, the cleaning control unit 101a instructs the user via the operation display unit 103 to check each part of the diffusion module 70.

[0309] In step SB14, the cleaning control unit 101a checks the air flow rate in the diffusion module 70. The air flow rate is checked, for example, based on the detection signal from the flow meter 108i.

[0310] In the following step SB15, the cleaning control unit 101a stops the air pump 108c (air pump: OFF). Note that the air pump 108c may be stopped, for example, when the detected pressure of the second pressure gauge 108h reaches a predetermined specified pressure.

[0311] In the following step SB16, the cleaning control unit 101a determines whether the air flow rate is normal. This determination can be made by comparing the air flow rate confirmed in step SB14 with the air flow rate newly confirmed in step SB16 after the air pump 108c has been stopped.

[0312] If the determination in step SB16 is YES, the cleaning control unit 101a proceeds to step SB17 in Figure 9. On the other hand, if the determination in step SB16 is NO, the cleaning control unit 101a proceeds to step SB8 in Figure 9. The processing in step SB8 is as described above.

[0313] For example, if the process proceeds from the determination in step SB16 to step SB8, there is concern about abnormalities related to the diffusion module 70, such as an abnormal operation of the air pump 10c or an abnormal opening / closing of the fluid control valve 18b. In this case, the cleaning control unit 101a instructs the user via the operation display unit 103 to check each part of the diffusion module 70.

[0314] In step SB17, the cleaning control unit 101a authorizes the execution of head cleaning. Upon receiving this authorization, the head cleaning described below is permitted.

[0315] (German process for head cleaning) Figure 10 is a flowchart illustrating the specific process of head cleaning. The process shown in Figure 10 is performed, for example, immediately after the process in step SB17 in Figure 8 has been executed.

[0316] In the process shown in Figure 10, instead of opening and closing the fluid control valve 18b, or in addition to opening and closing the fluid control valve 18b, the orifice 18d may also be opened and closed. Furthermore, instead of automatically opening and closing the shutter 21 as in steps SC1 and SC13 described later, the discharge port 10a may be configured to be opened and closed manually by the shutter 21 or a cap similar to the shutter 21.

[0317] First, in step SC1, the cleaning control unit 101a operates the shutter 21 to close the discharge port 10a before the diffusion means 18 provides assistance.

[0318] In the subsequent step SC2, the cleaning control unit 101a closes the 12th valve V12, which acts as a solvent control valve, and activates the 2nd pump P2, which acts as a solvent pump. As a result, the solvent reaches the solvent supply pipe 54 directly upstream of the 12th valve V12.

[0319] In the subsequent step SC3, the cleaning control unit 101a waits for a predetermined time to allow the solvent pressure to rise.

[0320] In the subsequent step SC4, the cleaning control unit 101a closes the fluid control valve 18b. If the fluid control valve 18b was already closed when the process transitioned to step SC4, the cleaning control unit 101a maintains the fluid control valve 18b in the closed state.

[0321] In the subsequent step SC5, the cleaning control unit 101a activates the air pump 108c. This allows the dry air, as a fluid, to reach the second fluid pipeline 18a directly upstream of the fluid control valve 18b.

[0322] In the subsequent step SC6, the cleaning control unit 101a waits for a predetermined time with the fluid control valve 18b closed in order to wait for the pressure of the drying air to rise.

[0323] In the following step SC7, the cleaning control unit 101a opens the fluid control valve 18b. As a result, the dry air that had reached the second fluid pipeline 18a directly upstream of the fluid control valve 18b is injected from the fluid injection unit 18c.

[0324] At that time, the dry air is injected towards the second electrode plate 152 along the injection axis Aa in Figure 4A. The dry air forms an airflow along the injection axis Aa.

[0325] In the subsequent step SC8, the cleaning control unit 101a temporarily opens the 12th valve V12, which acts as a solvent control valve, for a predetermined period of time (temporarily open). As a result, solvent is ejected from the nozzle 12 for the predetermined period of time.

[0326] The solvent supplied from the nozzle 12 into the print head 1 flows along the flight axis Ax. This flight axis Ax intersects with the injection axis Aa, as described above. Therefore, the dry air sprayed from the fluid injection unit 18c along the injection axis Aa collides with the solvent flowing along the flight axis Ax. The collision of the dry air atomizes the solvent, and the atomized solvent diffuses into the print head 1. By pressurizing the dry air at this time, the solvent that collides with the dry air is atomized more reliably.

[0327] The atomized solvent strikes the second electrode plate 152. The second electrode plate 152 is then cleaned by the solvent. Even if the solvent that strikes the second electrode plate 152 were to form droplets, the droplets would be guided away from the discharge port 10a by the bent surface 152c. This suppresses leakage of the solvent from the discharge port 10a.

[0328] Furthermore, ink stains dissolved in the solvent flow through the housing 10 along the curved surface 152c, and are transported to locations that do not interfere with printing, such as corners inside the housing 10 along the extension line El (see the enclosed area Dp in Figure 4B).

[0329] Furthermore, as suggested by the order of steps SC7 and SC8, by ejecting the solvent after the spraying of dry air, the solvent can be sprayed towards the airflow that has already been formed by the dry air. This allows for more reliable atomization of the solvent. This is advantageous in ensuring controllability during solvent atomization.

[0330] Figure 11 is graph G1, which illustrates the relationship between air flow rate and solvent ejection timing. The horizontal axis of graph G1 shows the elapsed time since the air pump 108c was activated in step SC5. The vertical axis of Figure 11 shows the change in air flow rate based on the detection signal of the flow meter 108i.

[0331] In graph G1, time t0 represents the opening timing of the fluid control valve 18b, that is, the execution timing of step SC7. As shown in graph G1, when the fluid control valve 18b is opened at time ts, the flow rate of air injected from the fluid injection unit 18c decreases slightly from the peak value Pv, and then reaches a steady state (a state that is approximately constant over time).

[0332] Then, the cleaning control unit 101a according to this embodiment opens the 12th valve V12, which acts as a solvent control valve, at a timing after the air flow rate reaches its peak value Pv (for example, at any of time t0, t1, or t2 in Figure 11).

[0333] The 12th valve V12 may be open for a predetermined period of time, as indicated by the double arrow Ts connecting time t1 to time t2. By opening the 12th valve V12 for a predetermined period of time, the atomized solvent can be sprayed (scanned) over a wide area of ​​the second electrode plate 152.

[0334] It is not essential to spray the solvent after spraying the drying air. By reversing the order of steps SC7 and SC8, the system may be configured to spray the drying air after the solvent is sprayed.

[0335] The opening time of the 12th valve V12 in step SC8 is changed, for example, based on the detection signal from the attitude sensor 24. Changing the opening time based on the detection signal from the attitude sensor 24 is an example of "changing the cleaning sequence" in this embodiment.

[0336] For example, if the print head 1 has its discharge port 10a pointed downward along the vertical direction, the dry air and solvent can be brought into contact more reliably. In this case, the solvent is atomized more reliably, allowing for the atomization of a larger amount of solvent. Therefore, the opening time of the 12th valve V12 becomes relatively longer.

[0337] On the other hand, if the print head 1 has its discharge port 10a oriented horizontally or vertically upward, it becomes inconvenient for the drying air and solvent to collide. In this case, the atomization of the solvent is suppressed. Since the atomization of the solvent is suppressed, a smaller amount of solvent needs to be atomized, allowing for efficient use of the solvent. Therefore, the opening time of the 12th valve V12 becomes relatively shorter.

[0338] Before proceeding from step SC8 to step SC9, the solvent supply is stopped by closing the 12th valve V12. The cessation of the solvent supply means that the cleaning process (head cleaning) is stopped.

[0339] Therefore, in step SC9, the cleaning control unit 101a executes a solvent drying process. In this drying process, only the injection of drying air from the fluid injection unit 18c is performed. By injecting drying air without the presence of solvent, the second electrode plate 152 can be dried.

[0340] In the following step SC10, the cleaning control unit 101a closes the fluid control valve 18b. As a result, the injection of drying air from the fluid injection unit 118c is also temporarily stopped.

[0341] It is not mandatory to spray drying air in step SC9. The cleaning control unit 101a may wait for a predetermined time without spraying drying air. Even if it waits without spraying drying air, the inside of the print head 1 can be dried by the evaporation of the solvent. By reversing the execution order of steps SC9 and SC10 in Figure 10, a drying process without spraying drying air can be realized.

[0342] In the following step SC11, the cleaning control unit 101a determines whether the number of head cleaning operations, in which the components housed inside the print head 1 (e.g., the second electrode plate 152) are cleaned with solvent supplied from the solvent supply unit 105, has reached a predetermined number of repetitions. If the determination is NO, the cleaning control unit 101a returns the control process to step SC6. If the determination is YES, the cleaning control unit 101a proceeds the control process to step SC12. The number of repetitions may be stored in the control unit 101 in advance.

[0343] In other words, the cleaning control unit 101a according to this embodiment repeatedly performs the ejection of solvent from the solvent supply unit 105 and the diffusion of solvent by the diffusion means 18 until a predetermined number of repetitions is reached.

[0344] In the following step SC12, the cleaning control unit 101a stops the air pump 108c (air pump: OFF). In the following step SC13, the cleaning control unit 101a activates the suction device 22. The operation of the suction device 22 ventilates the inside of the print head 1, causing it to dry. This drying causes the solvent to evaporate. Activating the suction device 22 with the discharge port 10a closed by the shutter 21 contributes to drying the inside of the print head 1.

[0345] In other words, the cleaning control unit 101a according to this embodiment is configured to dry the inside of the print head 1 with the suction device 22 when the discharge port 10a is closed by the shutter 21.

[0346] Note that the process in step SC12 is not mandatory. Alternatively, instead of or in addition to the process in step SC12, a drying process using dry air, as in step SC9, may be performed after step SC11.

[0347] In the subsequent step SC14, the cleaning control unit 101a opens the shutter 21. This completes the control process illustrated in Figure 10.

[0348] <Significance of diffusion method 18> As described above, according to the embodiment, the diffusion means 18 diffuses the solvent as a liquid into the print head 1 (see Figure 4B). This reduces the amount of solvent sprayed when cleaning the print head 1. Reducing the amount of solvent sprayed suppresses solvent leakage from the print head 1. By suppressing solvent leakage, it becomes possible to clean the print head with solvent without using a solvent tray, a dedicated stand, etc. This makes it possible to clean the print head 1 without removing it from the production line.

[0349] Alternatively, instead of removing and moving the print head 1, it is conceivable to temporarily place the aforementioned solvent tray directly beneath the print head 1. However, this method requires the tray to be readily available. Furthermore, there is a risk of the solvent overflowing from the tray and contaminating the production line. By using the diffusion means 18 described above, such a tray becomes unnecessary. This improves user convenience.

[0350] Furthermore, as illustrated in Figure 4B, by intersecting the fluid as substance 200 with the flight axis Ax of the solvent, it becomes possible to collide the fluid with the solvent flowing along that flight axis Ax. By colliding the substances, the solvent can be diffused into the print head 1.

[0351] Furthermore, as explained with reference to Figure 11, by adjusting at least one (in this embodiment, both) of the timing of discharging or spraying the solvent within the print head 1 and the timing of crossing the flight axis Ax, it becomes possible to more reliably collide the fluid with the solvent flowing along the flight axis Ax. This contributes to the diffusion of the solvent within the print head 1.

[0352] Furthermore, as illustrated in Figures 4B and 6, by using a fluid as the substance to collide with the solvent, the solvent discharged or sprayed into the print head 1 can be guided to the components within the print head 1 based on the direction of fluid flow. Guiding the solvent to the components makes it easier to remove dirt attached to those components. This makes it possible to achieve a sufficient cleaning effect while reducing the amount of solvent sprayed.

[0353] Furthermore, as illustrated in Figures 4B and 6, by using a solvent as the fluid to collide with the solvent, the solvent discharged or sprayed into the print head 1 can be blown onto the components inside the print head 1 by the airflow. By blowing the solvent onto the components, the dirt attached to those components becomes easier to remove. This makes it possible to achieve a sufficient cleaning effect while reducing the amount of solvent sprayed.

[0354] Furthermore, as explained with reference to the symbol M1 in Figure 4B, the solvent discharged or sprayed into the print head 1 can be atomized with air and then sprayed onto the components inside the print head 1. Atomizing the solvent contributes to expanding the cleaning area of ​​the components. This makes it possible to achieve a sufficient cleaning effect while reducing solvent consumption.

[0355] Furthermore, by atomizing the solvent, leakage of the solvent can be suppressed regardless of the orientation of the print head 1. Even without positioning the print head 1 in a specific orientation during head cleaning, leakage of the solvent from within the print head 1 is suppressed. This suppression of solvent leakage regardless of the orientation of the print head 1 is advantageous when cleaning the print head 1 with a solvent while it is installed on the production line.

[0356] Furthermore, by suppressing solvent leakage regardless of the orientation of the print head 1, the flexibility in positioning the print head 1 can be increased. This improves the usability of the inkjet recording device I.

[0357] Furthermore, generally, as the inkjet recording device I is used repeatedly, ink-related dirt will gradually accumulate on the deflection electrode 15. In response to this, as illustrated in Figure 4B, by spraying dry air towards the deflection electrode 15, a solvent can be sprayed onto the deflection electrode 15. This makes it easier to remove the dirt adhering to the deflection electrode 15, which is advantageous in achieving a sufficient cleaning effect while reducing the amount of solvent consumed.

[0358] Furthermore, as illustrated in Figure 3, by positioning the fluid injection unit 18c on the first electrode plate 151 of the deflection electrode 15, the fluid injection unit 18c and the solvent flight axis Ax can be brought as close as possible. This is advantageous in ensuring more reliable solvent spraying and achieving sufficient cleaning effect while reducing solvent consumption.

[0359] Furthermore, generally, a high voltage is applied to the second electrode plate 152, which is not grounded. In that case, the charged ink will be attracted to the second electrode plate 152 more than to the grounded first electrode plate 151. The second electrode plate 152 is more prone to accumulating dirt than the first electrode plate 151.

[0360] In contrast, the fluid injection unit 18c according to this embodiment sprays air and solvent toward the second electrode plate 152 during diffusion by the diffusion means 18. This makes it possible to more reliably clean the second electrode plate 152, which is expected to accumulate dirt easily.

[0361] Furthermore, as illustrated in Figure 3, by providing a bent surface 152c on the second electrode plate 152, the solvent sprayed onto the second electrode plate 152 and the ink stains dissolved in that solvent can be guided away from the solvent flowing along the flight axis Ax. This suppresses the leakage of solvent and ink stains from the print head 1, and consequently improves the usability of the inkjet recording device I.

[0362] Furthermore, as illustrated in Figure 6, by arranging the fluid control valve 18b on the print head 1 and the air generation unit 108 on the controller 100, the print head 1 can be made more compact by removing the air generation unit 108 from the print head 1. This improves the usability of the inkjet recording device I.

[0363] Furthermore, as explained with reference to Figures 8 and 9, the cleaning control unit 101a, acting as a cleaning management unit, manages the amount of solvent used. This, combined with the diffusion of the solvent by the diffusion means 18, can further reduce solvent consumption.

[0364] Furthermore, as illustrated in Figure 29, the solvent is diffused by the diffusion means 18 while the print head 1 is mounted on the transport line L via the attachment / detachment part 9. This eliminates the need to remove the print head 1 from the transport line L, move it to a cleaning location, and then reinstall it in its original position after cleaning. This not only saves time and effort but also helps to prevent the print head 1 from falling during removal and to prevent a decrease in print cycle time.

[0365] Furthermore, by using an ink dilution solvent as the solvent diffused within the print head 1, a separate cleaning solvent becomes unnecessary. This improves the usability of the inkjet recording device I.

[0366] [Second Embodiment] Figure 12A is a diagram corresponding to Figure 4A showing a second embodiment of the inkjet recording device I. Figure 12B is a diagram corresponding to Figure 4B showing a second embodiment of the inkjet recording device I. Figure 13 is a diagram illustrating the internal structure of the print head 1 according to the second embodiment. In Figures 12A, 12B, and 13, elements having the same configuration and structure as in the previous embodiment are denoted by the same reference numerals as in that embodiment.

[0367] The inkjet recording apparatus I according to the second embodiment, like the first embodiment, is equipped with a diffusion module 70A that performs a first type of diffusion using air on a fluid as substance 200. This diffusion module 70A has a diffusion means 118 according to the second embodiment.

[0368] Furthermore, the diffusion means 118 according to the second embodiment, like the diffusion means 18 according to the first embodiment, can diffuse the solvent supplied to the print head 1 from the solvent supply unit 105, which acts as a liquid supply unit, and the solvent discharged or sprayed within the print head 1.

[0369] The diffusion means 118 according to the second embodiment has a fluid injection unit 118c that injects air, similar to the embodiment, but differs from the embodiment in terms of the configuration and arrangement of the fluid injection unit 118c.

[0370] In the second embodiment, the fluid injection unit 118c is composed of a separate component from the first electrode plate 151. Specifically, as shown in Figures 12A and 13, the fluid injection unit 118c is located between the gutter 16 and the first electrode plate 151 in the vertical direction. In the horizontal direction, the fluid injection unit 118c is positioned approximately at the same location as the tip of the gutter 16 (ink or solvent inlet) and the first electrode plate 151.

[0371] More specifically, the air injection axis Aa' in the fluid injection unit 118c extends toward the inclined surface 152b of the second electrode plate 152 in the deflection electrode 15, as illustrated in Figures 12A and 12B. In other words, the fluid injection unit 118c according to the second embodiment injects air toward the deflection electrode 15, particularly toward the inclined surface 152b of the second electrode plate 152.

[0372] More specifically, the air injection axis Aa' in the fluid injection unit 118c extends diagonally upward, as illustrated in Figure 12A, and intersects with the flight axis Ax. That is, in the fluid injection unit 118c according to the second embodiment, similar to the embodiment described above, the flight axis Ax of the solvent discharged from the nozzle 12 is interposed between the fluid injection unit 118c and the deflection electrode 15, particularly the second electrode plate 152.

[0373] The control unit 101 operates the air pump 108c with the fluid control valve 18b or orifice 18d closed. This allows the dry air to be pressurized. When the dry air is pressurized, opening the fluid control valve 18b or orifice 18d causes the dry air to be injected from the fluid injection unit 118c.

[0374] As illustrated by reference numeral M2 in Figure 12B, the diffusion means 118 directs air (dry air) sprayed from the fluid injection unit 118c onto the solvent supplied from the solvent supply unit 105. By directing the dry air onto the solvent, the solvent is diffused.

[0375] The configuration and process for atomizing the solvent with dry air are the same as in the above embodiment. The configuration of the cleaning control unit 101a, which performs various processes, is also the same as in the above embodiment.

[0376] [Third Embodiment] Figure 14A is a diagram corresponding to Figure 4A showing a third embodiment of the inkjet recording device I. Figure 14B is a diagram corresponding to Figure 4B showing the third embodiment. Figure 15 is a diagram corresponding to Figure 5 showing the third embodiment. Figure 16 is a diagram illustrating the control of the diffusion direction in the third embodiment. In Figures 14A, 14B, and 15, elements having the same configuration and structure as in the previous embodiments are denoted by the same reference numerals as in those embodiments.

[0377] The inkjet recording apparatus I according to the third embodiment is equipped with a diffusion module 207 that performs a first type of diffusion using air on a fluid as substance 200, similar to the embodiment described above. This diffusion module 207 has a diffusion means 218 according to the third embodiment.

[0378] The diffusion means 218 according to the third embodiment, like the diffusion means 18 and 118 according to the first and second embodiments, can diffuse the solvent supplied to the print head 1 from the solvent supply unit 105, which serves as a liquid supply unit, and the solvent discharged or sprayed within the print head 1.

[0379] Furthermore, as shown in Figures 14A and 14B, the fluid injection unit according to the third embodiment has a first injection unit 218c and a second injection unit 218d. The first injection unit 218c is arranged on the first electrode plate 151, as is the fluid injection unit 18c in the above embodiment (first embodiment). The second injection unit 218d is composed of a separate component from the first electrode plate 151, as is the fluid injection unit 118c in the second embodiment.

[0380] The first injection unit 218c injects air as a fluid. The air injection axis Ab in the first injection unit 218c extends toward the second opposing surface 152a of the second electrode plate 152 in the deflection electrode 15, as shown, for example, in Figures 14A and 14B. That is, the first injection unit 218c injects air toward the deflection electrode 15, in particular toward the second opposing surface 152a of the second electrode plate 152.

[0381] More specifically, the air injection axis (hereinafter referred to as the "first injection axis") Ab in the first injection section 218c extends diagonally upward, as illustrated in Figure 14A, and intersects with the flight axis Ax. That is, the first injection section 218c is positioned such that the flight axis Ax of the solvent discharged from the nozzle 12 is interposed between the first injection section 218c and the deflection electrode 15, particularly the second electrode plate 152.

[0382] The second injection unit 218d injects auxiliary air, so to speak, to change the direction of the air injected from the first injection unit 218c. The air injection axis Ab' of the second injection unit 218d extends toward the inclined surface 152b of the second electrode plate 152 in the deflection electrode 15, as shown, for example, in Figures 14A and 14B. That is, the second injection unit 218d injects air toward the deflection electrode 15, in particular toward the inclined surface 152b of the second electrode plate 152.

[0383] More specifically, the air injection axis Ab' of the second injection unit 218d (hereinafter referred to as the "second injection axis") extends diagonally upward, as illustrated in Figure 14A, and intersects with the flight axis Ax. In other words, the second injection unit 218d is positioned such that the flight axis Ax of the solvent discharged from the nozzle 12 is interposed between the second injection unit 218d and the deflection electrode 15, particularly the second electrode plate 152.

[0384] Here, as shown in Figure 14A, the orientation of the first injection axis Ab is different from the orientation of the second injection axis Ab'. The first injection axis Aa and the second injection axis Aa' intersect each other. The intersection point Pc of the first injection axis Aa and the second injection axis Aa' is located between the first electrode plate 151 and the second electrode plate 152. As shown in Figure 14A, the flight axis Ax is interposed between the second electrode plate 152 and the intersection point Pc of the first injection axis Aa and the second injection axis Aa'.

[0385] Furthermore, as shown in Figure 15, the diffusion means 218 according to the third embodiment includes, in addition to the second fluid conduit 18a and fluid control valve 18b similar to those in the previous embodiment, a third fluid conduit 18e branched from the second fluid conduit 18a and a second fluid control valve 18f located in the third fluid conduit 18e. The second fluid control valve 18f corresponds to the "23rd valve V23" in Figure 15. The configuration of the air generation unit 108 connected to the second fluid conduit 18a is the same as in the previous embodiment.

[0386] The third fluid conduit 18e is the path through which the fluid (air) supplied from the air generation unit 108 flows. The upstream end of the third fluid conduit 18e is connected to an intermediate point in the second fluid conduit 18a. The downstream end of the third fluid conduit 18e is connected to the second injection unit 218d.

[0387] The second fluid control valve 18f is a control valve for controlling the injection of air generated by the air generation unit 108. The second fluid control valve 18f is composed of a solenoid valve electrically connected to the control unit 101. The second fluid control valve 18f operates by receiving a control signal from the control unit 101. When the second fluid control valve 18f operates, the third fluid pipeline 18e is opened and closed.

[0388] The control unit 101 can open both the fluid control valve 18b and the second fluid control valve 18f, close both the fluid control valve 18b and the second fluid control valve 18f, or selectively open one of the fluid control valve 18b or the second fluid control valve 18f. By appropriately controlling which valve to open, the direction of the airflow that collides with the solvent flowing along the flight axis Ax can be changed.

[0389] For example, as shown in Figure 16, when both the fluid control valve 18b and the second fluid control valve 18f are opened, an airflow C3 is generated, which is a combination of the airflow C1 from the first injection unit 218c along the first injection axis Aa and the airflow C2 from the second injection unit 218d along the second injection axis Aa'.

[0390] As shown in Figure 16, the flow direction of this combined airflow C3 differs from the flow direction of the airflow C1 produced by the air injected from the first injection unit 218c alone, and the flow direction of the airflow C2 produced by the air injected from the second injection unit 218d alone.

[0391] In this way, by using different methods—opening both the fluid control valve 18b and the second fluid control valve 18f, opening the fluid control valve 18b and closing the second fluid control valve 18f, and closing the fluid control valve 18b and opening the second fluid control valve 18f—the direction of the airflow generated by the air can be changed.

[0392] By changing the direction of the airflow, the direction of the mist (atomized solvent) Cm, which is generated when the airflow collides with the solvent flow (solvent flow Cy) along the flight axis Ax, can also be changed. The direction of the mist Cm can be selectively used by opening and closing the fluid control valve 18b and the second fluid control valve 18f. This enables cleaning over a wider area.

[0393] Alternatively, by using a control valve with adjustable opening, the flow velocity or flow rate of the air injected from the first injection unit 218c and the flow velocity or flow rate of the air injected from the second injection unit 218d can be controlled individually. This makes it possible to control the direction in which the mist flows more precisely.

[0394] Figure 17 is a flowchart illustrating the specific head cleaning process in the third embodiment. The processes in steps SD1, SD2, SD3, SD5, SD19, SD20, SD21, and SD22 in Figure 17 are substantially the same as the processes in steps SC1, SC2, SC3, SC5, SC11, SC12, SC13, and SC14 in Figure 10, respectively.

[0395] Furthermore, the process in step SD4 is substantially the same as the process in step SC4 in Figure 10, except that both the fluid control valve 18b and the second fluid control valve 18f are closed, as in the third embodiment, or only the fluid control valve 18b is closed, as in the first and second embodiments.

[0396] In the third embodiment, the flow in Figure 17 differs from the flow in Figure 10 in terms of the processing performed from step SD6 to step SD11.

[0397] Specifically, in step SD5, which is configured similarly to step SC5 in Figure 10, the cleaning control unit 101a activates the air pump 108c. As a result, dry air as a fluid reaches the second fluid conduit 18a directly upstream of the fluid control valve 18b and the third fluid conduit 18e in the direct flow of the second fluid control valve 18f.

[0398] In the subsequent step SD6, the cleaning control unit 101a waits for a predetermined time with both the fluid control valve 18b and the second fluid control valve 18f closed in order to wait for the pressure of the drying air to rise.

[0399] In the subsequent step SD7, the cleaning control unit 101a opens both the fluid control valve 18b and the second fluid control valve 18f. As a result, the dry air that had reached the second fluid conduit 18a directly upstream of the fluid control valve 18b is injected from the first injection unit 218c. In parallel with this, the dry air that had reached the third fluid conduit 18e directly upstream of the second fluid control valve 18f is injected from the second injection unit 218d.

[0400] At that time, the airflow C1 of dry air injected from the first injection unit 218c and the airflow C2 of dry air injected from the second injection unit 218d combine to form an airflow C3 for atomizing the solvent (see the lower part of Figure 16).

[0401] In the subsequent step SD8, the cleaning control unit 101a temporarily opens the 12th valve V12, which acts as a solvent control valve, for a predetermined period of time (temporarily open). As a result, solvent is ejected from the nozzle 12 for the predetermined period of time.

[0402] The solvent supplied from the nozzle 12 into the print head 1 flows along the flight axis Ax. This flight axis Ax intersects with the injection axis Aa, as described above. Therefore, the dry air sprayed from the first injection section 218c and the second injection section 218d along the injection axis Aa collides with the solvent flowing along the flight axis Ax. The collision of the dry air atomizes the solvent, and the atomized solvent diffuses into the print head 1. At this time, the atomization of the solvent is promoted by pressurizing the dry air.

[0403] Here, the atomized solvent (mist Cm) flows in a direction corresponding to the flow direction of the synthesized airflow C3, as shown in the lower part of Figure 16.

[0404] The atomized solvent comes into contact with the second electrode plate 152. The second electrode plate 152 is then cleaned by this solvent. As mentioned above, even if the solvent that comes into contact with the second electrode plate 152 forms droplets, the leakage of the solvent from the discharge port 10a is suppressed because it is guided by the bent surface 152c.

[0405] In the subsequent step SD9, the cleaning control unit 101a closes both the fluid control valve 18b and the second fluid control valve 18f. As a result, the first injection unit 218c and the injection of drying air from the first injection unit 218c are temporarily stopped.

[0406] In the subsequent step SD10, the cleaning control unit 101a, similar to step SD6, waits for a predetermined time with both the fluid control valve 18b and the second fluid control valve 18f closed in order to wait for the pressure of the drying air to rise.

[0407] In the subsequent step SD11, the cleaning control unit 101a opens the fluid control valve 18b while maintaining the second fluid control valve 18f in a closed state. As a result, the dry air that had reached the second fluid pipeline 18a directly upstream of the fluid control valve 18b is injected from the first injection unit 218c.

[0408] At that time, the dry air sprayed from the first injection unit 218c forms an airflow C1 for atomizing the solvent (see upper part of Figure 16). The direction in which this airflow C1 flows is different from that of the airflow C3 formed in step SD7.

[0409] In the subsequent step SD12, the cleaning control unit 101a temporarily opens the 12th valve V12, which acts as a solvent control valve, for a predetermined period of time (temporarily open). As a result, solvent is ejected from the nozzle 12 for the predetermined period of time.

[0410] The solvent supplied from the nozzle 12 into the print head 1 flows along the flight axis Ax. This flight axis Ax intersects with the injection axis Aa, as described above. Therefore, the dry air sprayed from the first injection unit 218c along the injection axis Aa collides with the solvent flowing along the flight axis Ax. The collision of the dry air atomizes the solvent, and the atomized solvent diffuses into the print head 1. At this time, the atomization of the dry air is promoted by pressurizing the dry air.

[0411] Here, the atomized solvent (mist Cm) flows in the direction corresponding to the flow direction of the airflow C1, as shown in the upper part of Figure 16.

[0412] The atomized solvent comes into contact with a different part of the second electrode plate 152 than the part in step SD8. The second electrode plate 152 is then cleaned by this solvent. As mentioned above, even if the solvent that comes into contact with the second electrode plate 152 forms droplets, the leakage of the solvent from the discharge port 10a is suppressed because it is guided by the bent surface 152c.

[0413] In the subsequent step SD13, the cleaning control unit 101a closes the fluid control valve 18b while keeping the second fluid control valve 18f closed. As a result, the injection of drying air from the first injection unit 218c is also temporarily stopped.

[0414] In the subsequent step SD14, the cleaning control unit 101a, similar to steps SD6 and SD9, waits for a predetermined time with both the fluid control valve 18b and the second fluid control valve 18f closed in order to wait for the dry air pressure to rise.

[0415] In the subsequent step SD15, the cleaning control unit 101a opens the second fluid control valve 18f while maintaining the fluid control valve 18b in a closed state. As a result, the dry air that had reached the third fluid pipeline 18e directly upstream of the second fluid control valve 18f is injected from the second injection unit 218d.

[0416] At that time, the dry air sprayed from the second injection unit 218d forms an airflow C2 for atomizing the solvent (see the middle section of Figure 16). The direction in which this airflow C2 flows is different from the airflows C1 and C3 formed in steps SD7 and SD11.

[0417] In the subsequent step SD16, the cleaning control unit 101a temporarily opens the 12th valve V12, which acts as a solvent control valve, for a predetermined period of time (temporarily open). As a result, solvent is ejected from the nozzle 12 for the predetermined period of time.

[0418] The solvent supplied from the nozzle 12 into the print head 1 flows along the flight axis Ax. This flight axis Ax intersects with the injection axis Aa, as described above. Therefore, the dry air sprayed from the second injection unit 218d along the injection axis Aa collides with the solvent flowing along the flight axis Ax. The collision of the dry air atomizes the solvent, and the atomized solvent diffuses into the print head 1. By pressurizing the dry air at this time, the solvent that collides with the dry air is atomized more reliably.

[0419] Here, the atomized solvent (mist Cm) flows in a direction corresponding to the flow direction of the airflow C2, as shown in the middle section of Figure 16.

[0420] The atomized solvent comes into contact with a different part of the second electrode plate 152 than the area covered by steps SD8 and SD12. The second electrode plate 152 is then cleaned by this solvent. As mentioned above, even if the solvent that comes into contact with the second electrode plate 152 forms droplets, the leakage of the solvent from the discharge port 10a is suppressed because it is guided by the bent surface 152c.

[0421] In the subsequent step SD17, the cleaning control unit 101a closes the second fluid control valve 18f while keeping the fluid control valve 18b closed. As a result, the injection of drying air from the first injection unit 218c is also temporarily stopped.

[0422] In the subsequent step SD18, the cleaning control unit 101a performs a drying process similar to that in step SC9 of Figure 10. Drying air may be used during this drying process as appropriate.

[0423] As illustrated in Figures 14A and 14B above, the fluid injection unit according to the second embodiment includes a first injection unit 218c that injects air as a fluid, and a second injection unit 218d that injects auxiliary air to change the injection direction of the air injected from the first injection unit 218c.

[0424] This configuration allows the direction of air spray to be changed by auxiliary air. This enables control over the diffusion direction of the solvent as a liquid. As a result, the solvent can be sprayed over a wider area. This expands the cleaning area within the print head 1, making it possible to achieve sufficient cleaning effect while reducing solvent consumption.

[0425] [Fourth Embodiment] Figure 18A is a diagram corresponding to Figure 4A showing a fourth embodiment of the inkjet recording device I. Figure 18B is a diagram corresponding to Figure 4B showing the fourth embodiment. Figure 19 is a diagram corresponding to Figure 5 showing the fourth embodiment. Figure 20 is a diagram illustrating the control of the diffusion direction in the fourth embodiment. In Figures 18A, 18B, and 19, elements having the same configuration and structure as in the previous embodiments are denoted by the same reference numerals as in those embodiments.

[0426] The inkjet recording apparatus I according to the fourth embodiment includes a diffusion module 70C that performs a second type of diffusion using a solvent as the fluid substance 200. This diffusion module 70B has a diffusion means 318 according to the fourth embodiment.

[0427] Furthermore, the diffusion means 318 according to the fourth embodiment, similar to the diffusion means 18 according to the first embodiment, can diffuse the solvent supplied from the solvent supply unit 105, which acts as a liquid supply unit, to the print head 1 and discharged or sprayed within the print head 1.

[0428] Unlike the first, second, and third embodiments, the diffusion means 318 according to the fourth embodiment has a fluid injection unit 318c that injects a solvent as a fluid.

[0429] The fluid injection unit 318c according to the fourth embodiment may be composed of a separate component from the first electrode plate 151, as in the second embodiment, or it may be placed on the first electrode plate 151, as illustrated in Figures 18A and 18B.

[0430] Furthermore, the solvent injection axis Ac in the fluid injection unit 318c extends toward the second opposing surface 152a of the second electrode plate 152 of the deflection electrode 15, as illustrated in Figures 18A and 18B. In other words, the fluid injection unit 318c according to the fourth embodiment injects the solvent toward the deflection electrode 15, particularly toward the second opposing surface 152a of the second electrode plate 152.

[0431] More specifically, the solvent injection axis Ac in the fluid injection unit 318c extends diagonally upward, as illustrated in Figure 18A, and intersects with the flight axis Ax. That is, in the fourth embodiment, the fluid injection unit 318c is arranged such that the flight axis Ax of the solvent discharged from the nozzle 12 is interposed between the fluid injection unit 318c and the deflection electrode 15, particularly the second electrode plate 152, similar to the first embodiment.

[0432] Furthermore, as shown in Figure 19, the diffusion means 318 according to the fourth embodiment includes, in addition to the fluid injection unit 318c, a branch pipe 318a branched from the second solvent pipe 54b, a fifth pump P5 acting as an air pump located in the branch pipe 318a, and a fluid control valve 318b also located in the branch pipe 318a. The fluid control valve 318b corresponds to the "22nd valve V22" in Figure 19.

[0433] The branch pipe 318a is the path through which the fluid (solvent) supplied from the solvent supply unit 105 flows. The branch pipe 318a has an upstream end that is connected to a point along the route from the upstream end (connection part B3) of the second solvent pipe 54b to the second pump P2, and a downstream end that is connected to the fluid injection unit 318c. The fifth pump P5 and the fluid control valve 318b are arranged in the branch pipe 318a in order from the upstream side.

[0434] The fluid control valve 318b is a control valve for controlling the injection of air generated by the air generation unit 108. The fluid control valve 318b is composed of a solenoid valve electrically connected to the control unit 101. The fluid control valve 318b operates in response to a control signal from the control unit 101. When the fluid control valve 318b operates, the branch pipeline 318a, particularly the branch pipeline 318a upstream of the fluid injection unit 318c, is opened and closed.

[0435] The fifth pump P5 is a suction pump that draws solvent from the solvent hollow needle 53 to the fluid control valve 318b via the solvent supply pipe 54 (particularly the second solvent pipe 54b) and the branch pipe 318a, thereby creating a flow. The fifth pump P5 is electrically connected to the control unit 101 and operates by receiving control signals from the control unit 101.

[0436] The control unit 101 operates the fifth pump P5 with the fluid control valve 318b closed. This allows the solvent to be pressurized. When the fluid control valve 318b is opened while the solvent is pressurized, the solvent is injected from the fluid injection unit 318c.

[0437] As illustrated by reference numeral M4 in Figure 18B, the diffusion means 318 directs the solvent discharged or sprayed from the fluid injection unit 318c onto the solvent supplied from the solvent supply unit 105 and ejected from the nozzle 12. By colliding the two types of solvents, a solvent flow (combined flow Cn in Figure 20) is formed by these solvents. Depending on the direction (orientation) of this solvent flow, the solvent is diffused into the print head 1.

[0438] Here, the fluid injection unit 318c changes the flow rate or velocity of the solvent injected from the fluid injection unit 318c according to the pressure of the solvent pressurized by the fifth pump P5, the time spent pressurizing, etc. This makes it possible to change the direction of the solvent flow generated by the collision of the solvent injected from the fluid injection unit 318c with the solvent ejected from the nozzle 12 (solvent flowing along the flight axis Ax).

[0439] Figure 20 illustrates the combined solvent flow (hereinafter also referred to as the "combined flow") Cn, which is produced by the collision of the solvent flow along the flight axis Ax (first solvent flow Cv) and the solvent flow along the injection axis Ac injected from the fluid injection unit 318c (second solvent flow Cw). The direction of the arrows indicating each flow indicates the direction of that flow, and the length of the arrows indicates the flow velocity or flow rate of that flow.

[0440] As shown in Figure 20, the flow direction of the combined flow Cn changes with increases or decreases in the flow velocity or flow rate of the second solvent flow Cw. For example, when the flow velocity or flow rate of the second solvent flow Cw is high, the flow direction of the combined flow Cn is more influenced by the flow direction of the second solvent flow Cw than when the flow velocity or flow rate is low. The greater the influence of the flow direction of the second solvent flow Cw, the closer the flow direction of the combined flow Cn will be to the flow direction of the second solvent flow Cw.

[0441] In this way, by changing the flow velocity or flow rate of the second solvent flow Cw, the flow direction of the combined flow Cn, which is generated by the collision of the second solvent flow Cw with the first solvent flow Cv) along the flight axis Ax, can be changed. The flow direction of the combined flow Cn can be selectively controlled through the flow velocity or flow rate of the second solvent flow Cw. This enables cleaning over a wider area.

[0442] Note that the example in Figure 20 shows the flow direction of the combined solvent flow Cn along the up-down and left-right directions, based on the positional relationship in Figures 18A and 18B. In reality, by causing the first solvent flow Cv and the second solvent flow Cw to collide, the solvent can be diffused not only in the up-down and left-right directions, but also in the front-to-back direction perpendicular to the plane of the paper in Figures 18A, 18B, and 20 (as illustrated in Figure 29). This enables cleaning over a wider area.

[0443] Figure 21 is a flowchart illustrating the specific head cleaning process in the fourth embodiment. The processes of steps SE1, SE2, SE3, SE4, SE8, SE9, SE10, SE11, SE13, and SE14 in Figure 21 are substantially the same as the processes of steps SC1, SC2, SC3, SC4, SC8, SC9, SC10, SC13, and SC14 in Figure 10, respectively.

[0444] Furthermore, the processes in steps SE5 and SE12 are substantially the same as those in steps SC5 and SC12 of Figure 10, except that they involve either activating or stopping the fifth pump P5 for dispensing the solvent, as in the fourth embodiment, or activating or stopping the air pump 108c for dispensing air, as in the first embodiment.

[0445] Furthermore, the processes in steps SE6 and SE7 are substantially the same as those in steps SE6 and SE7 of Figure 10, except that, as in the fourth embodiment, the solvent is ejected from the fluid injection unit 318c by opening the fluid control valve 318b after waiting for the solvent pressure to rise, or, as in the first embodiment, the dry air is ejected from the fluid injection unit 18c by opening the fluid control valve 18b after waiting for the dry air pressure to rise.

[0446] As described above, the diffusion means 318 according to the fourth embodiment causes the solvent to collide with the solvent being sprayed in the print head 1 as a fluid. The diffusion direction of the former solvent can be controlled by adjusting the flow rate or velocity of the latter solvent. This allows the solvent to be sprayed over a wider area. As a result, the cleaning area within the print head 1 can be expanded, and sufficient cleaning effect can be achieved while reducing solvent consumption.

[0447] [Fifth Embodiment] Figure 22A is a diagram corresponding to Figure 4A showing a fifth embodiment of the inkjet recording device I. Figure 22B is a diagram corresponding to Figure 4B showing the fifth embodiment. Figure 23 is a diagram corresponding to Figure 5 showing the fifth embodiment. Figure 24 is a diagram illustrating the control of the diffusion direction in the fifth embodiment. In Figures 22A, 22B, and 23, elements having the same configuration and structure as in the previous embodiments are denoted by the same reference numerals as in those embodiments.

[0448] The inkjet recording apparatus I according to the fifth embodiment includes a diffusion module 70D that performs a third type of diffusion using mechanical parts on a solid as a substance 200. This diffusion module 70D has a diffusion means 418 according to the fifth embodiment.

[0449] The diffusion means 418 according to the fifth embodiment, as shown in Figures 22A, 22B, and 23, is composed of a movable member 418a that can move to a position that intersects with the flight axis Ax of the liquid discharged or sprayed in the print head 1 (hereinafter referred to as the "intersection position"), and a first moving mechanism 418b that moves the movable member 418a to the intersection position. The first moving mechanism 418b is shown only in Figure 23. The movable member 418a is exemplified by a solid (machine part) as the substance 200 for diffusing the solvent in the fifth embodiment.

[0450] More specifically, the movable member 418a is a plate-shaped member that can rotate around a predetermined rotation axis Or. The movable member 418a can move between a retracted position that does not intersect the flight axis Ax, as illustrated in Figure 22A, and an intersecting position that intersects the flight axis Ax, as illustrated in Figure 22B. The retracted position is used during printing operations. The intersecting position is used during head cleaning.

[0451] Meanwhile, the first moving mechanism 418b moves the moving member 418a between the retracted position and the intersection position, and also rotates the moving member 418a around the rotation axis Or. The first moving mechanism 418b is composed of, for example, one or more stepping motors electrically connected to the control unit 101. The control unit 101 moves and rotates the moving member 418a via the first moving mechanism 418b by inputting control signals to one or more stepping motors.

[0452] Here, the rotation axis Or extends in a direction perpendicular to both the direction in which the flight axis Ax extends (up and down direction) and the direction in which the first electrode plate 151 and the second electrode plate 152 are aligned (left and right direction) (front and back direction).

[0453] The diffusion means 418 directs the solvent supplied from the solvent supply unit 105 and ejected from the nozzle 12 onto the movable member 418a, which has been moved to an intersection position. This deflects the direction of the solvent flow relative to the flight axis Ax. Furthermore, by rotating the movable member 418a, the solvent is diffused into the print head 1 according to the angle of rotation.

[0454] Here, the up-down, left-right, and right directions in Figure 24 are the same as the up-down, left-right, and right directions in Figure 20. As shown in Figure 24, by setting the rotation angle of the moving member 418a to +45° or -45°, it is possible to generate a solvent flow (solvent flow Co) to the left as viewed from the moving member 418a, i.e., to the second electrode plate 152, or to generate a solvent flow Co to the right as viewed from the moving member 418a, i.e., to the first electrode plate 151.

[0455] Furthermore, as shown in the middle section of Figure 24, by setting the rotation angle of the moving member 418a to 0°, it is possible to generate solvent flow Co that reaches both the left and right sides from the perspective of the moving member 418a, that is, both the second electrode plate 152 and the first electrode plate 151.

[0456] In this way, the direction of solvent diffusion can be controlled by appropriately changing the rotation angle of the movable member 418a. This allows for cleaning of a wider area by the solvent diffused by the movable member 418a.

[0457] Figure 25 is a flowchart illustrating the specific head cleaning process in the fifth embodiment. The processes in steps SF1, SF2, SF3, SF6, SF7, SF8, SF10, and SF11 in Figure 26 are substantially the same as the processes in steps SC1, SC2, SC3, SC4, SC8, SC9, SC11, SC13, and SC14 in Figure 10, respectively.

[0458] Here, in step SF4, the cleaning control unit 101a activates the first moving mechanism 418b to move the moving member 418a from the retracted position in Figure 22A to the intersection position in Figure 22B.

[0459] In the subsequent step SF5, the cleaning control unit 101a activates the first moving mechanism 418b to rotate the moving member 418a to a predetermined angular position around the rotation axis Or. Note that the process in step SF5 may be performed after step SF6.

[0460] Furthermore, in step SF6, instead of spraying the solvent from the nozzle 12 over a predetermined period of time as in step SC8 of Figure 10, the solvent may be sprayed continuously. As long as NO is determined in step SF8, the solvent will be sprayed continuously. In this case, the moving member 418a will change its angular position while intersecting with the solvent sprayed from the nozzle 12.

[0461] Subsequently, in step SF9, the cleaning control unit 101a activates the first moving mechanism 418b to move the moving member 418a from the intersection position in Figure 22B to the retracted position in Figure 22A.

[0462] As described above, according to the fifth embodiment, the moving member 418a is positioned to intersect with the flight axis Ax of the solvent. This makes it possible to cause the moving member 418a, as substance 200, to collide with the solvent flowing along the flight axis Ax. By causing the moving member 418a to collide with the solvent, the solvent can be diffused into the print head 1.

[0463] [Sixth Embodiment] Figure 26A is a diagram corresponding to Figure 4A showing a sixth embodiment of the inkjet recording device I. Figures 26B and 26C are diagrams corresponding to Figure 4B showing the sixth embodiment, respectively. Figure 27 is a diagram corresponding to Figure 5 showing the sixth embodiment. In Figures 26A, 26B, 26C, and 27, elements having the same configuration and structure as those in the previous embodiments are denoted by the same reference numerals as in those embodiments.

[0464] The inkjet recording apparatus I according to the sixth embodiment includes a diffusion module 70E that performs a third type of diffusion using mechanical parts on a solid as a substance 200. This diffusion module 70E has a diffusion means 518 according to the sixth embodiment.

[0465] Here, the charging electrode 13 or deflection electrode 15 according to the sixth embodiment is configured to be movable to a position that intersects with the flight axis Ax of the liquid ejected or sprayed within the print head 1 (hereinafter referred to as the "intersection position" as in the fifth embodiment).

[0466] Furthermore, as shown in Figures 26A, 26B, 26C, and 27, the diffusion means 518 according to the sixth embodiment consists of a charge electrode 13 or deflection electrode 15 that can move to an intersection position, and a second moving mechanism 518b that moves the charge electrode 13 or deflection electrode 15 to the intersection position. The second moving mechanism 518b is shown only in Figure 27.

[0467] In this embodiment, the second electrode plate 152 of the charging electrode 13 and deflection electrode 15 is movable to the intersection position. This second electrode plate 152, together with the second moving mechanism 518b, constitutes the diffusion means 518. The second electrode plate 152 exemplifies a solid (machine part) as the substance 200 for which the solvent is diffused in the sixth embodiment.

[0468] It is not essential to use the second electrode plate 152 as the substance 200 for diffusing the solvent. The first electrode plate 151 or the charged electrode 13 may be used instead.

[0469] More specifically, the second electrode plate 152 according to the sixth embodiment is a plate-shaped member that can rotate around a predetermined rotation axis Or', as shown in Figures 26B and 26C. The second electrode plate 152 can move between a retracted position that does not intersect the flight axis Ax, as illustrated in Figure 26A, and an intersecting position that intersects the flight axis Ax, as illustrated in Figures 26B and 26C. The retracted position is used during printing operations. The intersecting position is used during head cleaning.

[0470] Meanwhile, the second moving mechanism 518b moves the second electrode plate 152 between the retracted position and the crossing position, and rotates the second electrode plate 152 around the rotation axis Or'. The second moving mechanism 518b is composed of, for example, one or more stepping motors electrically connected to the control unit 101. The control unit 101 moves and rotates the second electrode plate 152 via the second moving mechanism 518b by inputting control signals to one or more stepping motors.

[0471] Here, the rotation axis Or' extends in a direction perpendicular to both the direction in which the flight axis Ax extends (up and down direction) and the direction in which the first electrode plate 151 and the second electrode plate 152 are aligned (left and right direction) (front and back direction).

[0472] The diffusion means 518 applies the solvent supplied from the solvent supply unit 105 and ejected from the nozzle 12 to the second electrode plate 152, which has been moved to the intersection position. This deflects the direction of the solvent flow relative to the flight axis Ax, and at the same time, the second electrode plate 152 is directly cleaned by the solvent. Furthermore, by rotating the second electrode plate 152, the solvent is diffused into the print head 1 according to the angle of rotation.

[0473] Here, the direction of solvent diffusion can be controlled by appropriately changing the rotation angle of the second electrode plate 152. In this way, a wider area can be cleaned by the solvent diffused by the second electrode plate 152.

[0474] Figure 28 is a flowchart illustrating the specific head cleaning process in the sixth embodiment. The processes in steps SG1, SG2, SG3, SG6, SG7, SG8, ​​SG10, and SG11 in Figure 28 are substantially the same as the processes in steps SC1, SC2, SC3, SC4, SC8, SC9, SC11, SC13, and SC14 in Figure 10, respectively.

[0475] Here, in step SG4, the cleaning control unit 101a activates the second moving mechanism 518b to move the second electrode plate 152 from the retracted position in Figure 26A to the crossing position in Figure 26B.

[0476] In the subsequent step SG5, the cleaning control unit 101a activates the second moving mechanism 518b to rotate the second electrode plate 152 to a predetermined angular position around the rotation axis Or', as shown in Figure 26C. Note that the process in step SG5 may be performed after step SG6.

[0477] Furthermore, in step SG6, instead of ejecting the solvent from the nozzle 12 over a predetermined period of time as in step SC8 of Figure 10, the solvent may be ejected continuously. As long as NO is determined in step SG8, ​​the solvent will be ejected continuously. In this case, the moving second electrode plate 152 will change its angular position while intersecting with the solvent ejected from the nozzle 12.

[0478] Subsequently, in step SG9, the cleaning control unit 101a activates the second moving mechanism 518b to move the second electrode plate 152 from the intersection position shown in Figures 26B and 26C to the retracted position shown in Figure 26AB.

[0479] As described above, according to the sixth embodiment, the charged electrode 13 or the deflection electrode 15 is crossed with respect to the flight axis Ax of the solvent. This makes it possible to cause the charged electrode 13 or the deflection electrode 15, as substance 200, to collide with the solvent flowing along the flight axis Ax. By causing the charged electrode 13 or the deflection electrode 15 to collide, the solvent can be diffused into the print head 1.

[0480] [Other Embodiments] In the third embodiment described above, it is not essential to open and close the fluid control valve 18b and the second fluid control valve 18f individually. The system may be configured to simultaneously open and close the fluid control valve 18b and the second fluid control valve 18f to inject dry air from the first injection unit 218c and the second injection unit 218d at the same time.

[0481] Furthermore, in the embodiments described above, the liquid diffused by the diffusion means was configured to be ejected from the nozzle 12 of the print head 1, but this disclosure is not limited to such configurations. The liquid to be diffused may be ejected from the cleaning nozzle 17 shown in Figure 3, or the liquid may be discharged or ejected from dedicated nozzles that are different from both the nozzle 12 and the cleaning nozzle 17.

[0482] In other words, the print head 1 according to this disclosure only needs to discharge or spray liquid from at least one of a nozzle 12 and a dedicated nozzle separate from the nozzle 12.

[0483] Figure 5 and the corresponding diagrams in each embodiment illustrate the ink and solvent pathways. Figure 31 shows a flow path diagram extracted from these diagrams that focuses on the elements related to cleaning the print head 1. In the flow path diagram shown in Figure 31, the controller 100 has an ink tank 106, which is a source of viscosity-adjusted ink. This ink tank 106 contains fast-drying ink. The ink tank 106 can also be called the "main tank." The ink in the ink tank 106 is supplied to the print head 1 by a third pump (ink pump) P3.

[0484] The controller 100 also has a solvent cartridge 51, which is a solvent supply source. This solvent cartridge 51 contains, for example, methyl ethyl ketone (MEK). The solvent in the solvent cartridge 51 is supplied to the print head 1 by a second pump (solvent pump) P2. Downstream of this second pump P2 is an open / close solvent solenoid valve V16 (not shown in Figure 5). When it is not necessary to supply solvent to the print head 1, the solvent solenoid valve V16 is closed.

[0485] The controller 100 has a first pump (suction pump or circulation pump) P1 that collects the ink liquid dropped into the gutter and returns it to the ink tank 106. When cleaning the print head 1 during the down-pressure process, the first pump P1 is activated to collect the cleaning liquid (solvent) from the print head 1 to the ink tank 106. Instead of collecting this cleaning liquid in the ink tank 106, the cleaning liquid may be collected in a conventionally known conditioning tank (not shown) installed separately in the controller 100.

[0486] The print head 1 has an ink line 360 ​​that receives ink from an ink tank 106 and a solvent line 362 that receives cleaning fluid (solvent) from a solvent cartridge 51. A 14th valve V14 is interposed in the ink line 360. A 12th valve V12 is interposed in the solvent line 362. The ink line 360 ​​and the solvent line 362 merge at their downstream ends to form a supply path 350. Reference numeral P in the figure indicates the merging point. This supply path 350 reaches the discharge port 12a of the nozzle 12. The nozzle discharge port 12a also communicates with a suction path 352, which is connected to the first pump P1 described above.

[0487] By opening the 14th valve V14, the ink liquid in the ink tank 106 is supplied to the supply path 350. On the other hand, by opening the 12th valve V12, the solvent (cleaning fluid) in the solvent cartridge 51 is supplied to the supply path 350.

[0488] The supply path 350 and the suction path 352 are composed of tubes, excluding the nozzle 12. These tubes may be made of PTFE tubes as in the conventional method, but it is preferable to use PFA tubes with the same diameter as conventional tubes. PFA tubes have a smoother surface and superior water repellency compared to PTFE tubes. This characteristic makes it easier for the cleaning solution to form a film inside the PFA tube.

[0489] A sixth valve V6 is installed in the suction path 352 (suction path 47), and by opening this sixth valve V6, the ink liquid and solvent in the print head 1 are recovered into the ink tank 106 by the first pump P1.

[0490] The print head 1 has a cleaning nozzle 17 for cleaning the nozzle 12 of the print head 1. As previously described, the cleaning nozzle 17 is used to clean the nozzle outlet 12a, etc., by spraying a cleaning liquid (solvent) from the cleaning nozzle 17. Specifically, the cleaning nozzle 17 may be positioned inside the print head 1 facing the nozzle outlet 12a, or it may be positioned facing the charging electrode 13 or the deflection electrode 15. This cleaning nozzle 17 is in communication with a solvent cartridge 51 via an openable and closable 15th valve V15. When cleaning the nozzle 12, the 12th valve V12 is opened and the 15th valve V15 is opened, and the solvent supplied from the solvent cartridge 51 is sprayed from the cleaning nozzle 17.

[0491] Alternatively, air may be drawn in from the cleaning nozzle 17 to dry the nozzle 12. Specifically, air may be supplied as shown by the arrow in Figure 31 by closing the solvent solenoid valve V16 and the 14th valve V14, opening the 12th valve V12 and the 6th valve V6, and operating the first pump P1. This can speed up the drying of the nozzle 12. Thus, the cleaning nozzle 17 may have both a solvent discharge function and an air intake function.

[0492] Furthermore, in a head structure or head control method that prevents cleaning fluid (solvent) from leaking outside the print head 1, various methods can be considered for removing and recovering the cleaning fluid (solvent) from inside the print head 1 after cleaning. For example, the cleaning fluid may be removed by supplying gas (increasing the internal pressure of the print head 1), or the internal pressure on the controller 100 side may be lowered to suck out and remove the cleaning fluid, or a path may be provided to recover the cleaning fluid in liquid form to the controller 100. Several of these methods may be combined.

[0493] In addition, the PLC903, acting as an external device 900, may perform control or commands related to head cleaning. For example, triggered by a cleaning command from the external device 900, the inkjet recording device I may display an indication that it is not in a printable state or send a response to the outside, or it may perform a cleaning operation combining the nozzle 12 and the cleaning nozzle 17, or it may move the cleaning liquid to nozzles other than nozzle 12, or it may move solvent from the solvent cartridge 51 or solvent reservoir 52 to the print head 1. [Explanation of Symbols]

[0494] S Inkjet Recording System I. Inkjet recording device 1. Print head 12 nozzles 13 Charged electrodes 15 Deflection electrode 151 1st electrode plate 151a 1st facing surface 152 Second electrode plate 152a 2nd facing surface 152b Slope 152c folded surface 16 Gutter 70 Diffusion Modules 18 Diffusion means 18b Fluid control valve 18c Fluid injection part 21 shutters 22 Aspirator 24. Attitude sensors 70A Diffusion Module 118 Dispersion means 118c Fluid injection part 70B Diffusion Module 218 Dispersion means 218c 1st injection part (fluid injection part) 218d 2nd injection part (fluid injection part) 70C Diffusion Module 318 Dispersion means 318c Fluid injection part 70D Diffusion Module 418 Dispersion means 418a Movable member 418b First moving mechanism 70E Diffusion Module 518 Dispersion means 518b Second moving mechanism 100 controllers 101 Control Unit 101a Cleaning Control Unit (Cleaning Management Unit) 104 Ink supply unit 105 Solvent supply unit (liquid supply unit) 108 Air generation unit 108g Air Dryer 108h Second pressure gauge 108i flow meter 1000 connection cables W Printing target Ax Flight axis (Liquid flight axis)

Claims

1. A print head comprising a nozzle for ejecting particulate ink, a charging electrode for charging the particulate ink ejected from the nozzle, a deflection electrode for deflecting the flight direction of the ink charged by the charging electrode, and a gutter for collecting the ink that has been made undeflected by the deflection electrode, and ejecting the ink deflected by the deflection electrode to the outside, A controller that supplies ink to the print head and sends control signals to the print head for controlling the nozzle, the charging electrode, and the deflection electrode, An inkjet recording apparatus comprising a connecting cable that fluidly and electrically connects the print head and the controller, The print head or the controller is provided with a liquid supply unit that supplies a liquid for dissolving the ink to the print head. The print head has a diffusion means for diffusing the liquid supplied from the liquid supply unit to the print head and discharged or sprayed within the print head. Inkjet recording device.

2. In the inkjet recording apparatus described in claim 1, The diffusion means diffuses the liquid by crossing the material with respect to the flight axis of the liquid discharged or sprayed within the print head. Inkjet recording device.

3. In the inkjet recording apparatus described in claim 2, The diffusion means adjusts at least one of the timing of discharging or spraying the liquid within the print head and the timing of crossing the material with respect to the flight axis, thereby causing the material to cross with respect to the flight axis. Inkjet recording device.

4. In the inkjet recording apparatus described in claim 3, The diffusion means adjusts both the timing of discharging or spraying the liquid within the print head and the timing of crossing the material with respect to the flight axis, thereby causing the material to cross with respect to the flight axis. Inkjet recording device.

5. In the inkjet recording apparatus described in claim 2, The diffusion means has a fluid injection unit that injects the fluid as the substance into the print head, and diffuses the liquid by making the fluid injected from the fluid injection unit cross the flight axis. Inkjet recording device.

6. In the inkjet recording apparatus described in claim 5, The fluid injection unit injects air as the fluid. Inkjet recording device.

7. In the inkjet recording apparatus described in claim 6, The diffusion means atomizes the liquid by directing the air sprayed from the fluid injection unit onto the liquid. Inkjet recording device.

8. In the inkjet recording apparatus described in claim 6, The fluid injection unit is arranged to inject the air toward the deflection electrode and to interpose the flight axis between itself and the deflection electrode. Inkjet recording device.

9. In the inkjet recording apparatus described in claim 8, The deflection electrode is composed of a grounded first electrode plate and a second electrode plate facing the first electrode plate. The fluid injection unit is positioned on the first electrode plate so as to inject the air toward the second electrode plate. Inkjet recording device.

10. In the inkjet recording apparatus described in claim 9, The second electrode plate is An inclined surface tilted in a direction away from the aforementioned flight axis, Extending from the tip of the inclined surface, and having a bent surface that is more steeply curved than the inclined surface in a direction away from the flight axis, Inkjet recording device.

11. In the inkjet recording apparatus described in claim 6, The controller has an air generating unit that generates the air to be injected from the fluid injection unit, The diffusion means includes a control valve within the print head for controlling the injection of air generated by the air generation unit. Inkjet recording device.

12. In the inkjet recording apparatus described in claim 6, The fluid injection unit is A first injection unit that injects air as the aforementioned fluid, The device includes a second injection unit that injects auxiliary air to change the injection direction of the air injected from the first injection unit, Inkjet recording device.

13. In the inkjet recording apparatus described in claim 5, The fluid injection unit injects the liquid as the fluid. Inkjet recording device.

14. In the inkjet recording apparatus described in claim 5, The controller has a cleaning management unit that manages the amount of liquid used during cleaning so that an amount of the liquid corresponding to the fluid sprayed from the fluid injection unit is supplied. Inkjet recording device.

15. In the inkjet recording apparatus described in claim 2, The diffusion means comprises a movable member that can move to a position intersecting the flight axis of the liquid discharged or sprayed in the print head, and a first moving mechanism that moves the movable member to the position intersecting the flight axis. Inkjet recording device.

16. In the inkjet recording apparatus described in claim 2, The charging electrode or the deflection electrode is configured to be movable to a position that intersects the flight axis of the liquid ejected or sprayed within the print head. The diffusion means comprises a charging electrode or deflection electrode that is movable to a position intersecting the flight axis, and a second moving mechanism that moves the charging electrode or deflection electrode to a position intersecting the flight axis. Inkjet recording device.

17. In the inkjet recording apparatus described in claim 1, The print head discharges or sprays the liquid from at least one of the nozzle and a separate dedicated nozzle. Inkjet recording device.

18. In the inkjet recording apparatus described in claim 1, The print head is equipped with a detachable part that is attached to and detached from the production line of the object to be printed by the print head. Inkjet recording device.

19. In the inkjet recording apparatus described in claim 18, The diffusion means diffuses the liquid by crossing the flight axis of the liquid discharged or sprayed within the print head while the print head is mounted on the production line by the attachment / detachment part. Inkjet recording device.

20. In the inkjet recording apparatus described in claim 1, The liquid supply unit supplies the ink solvent as a liquid to the print head. Inkjet recording device.

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