Inkjet recording system

Abstract

To provide an inkjet recording system, which is configured to prevent a printing head not placed on a cleaning placement part from being cleaned, so that a surrounding environment is not polluted.SOLUTION: An inkjet recording system comprises a placement detection part that detects that a printing head 1 is placed on a cleaning placement part 200, which is configured to send a signal based on a confirmation of the placement of the printing head 1 to a controller connected to the printing head 1 placed on the cleaning placement part 200, when detecting that the printing head 1 is placed thereon.SELECTED DRAWING: Figure 15

Description

[Technical field]

[0001] The present disclosure relates to inkjet recording systems. [Background technology]

[0002] 2. Description of the Related Art Inkjet recording devices for printing on a workpiece are known.

[0003] For example, Patent Document 1 discloses a so-called continuous inkjet recording device that circulates ink inside the device even when it is not printing on a workpiece. This inkjet recording device is equipped with a print head for ejecting ink droplets and a controller connected to the print head. This inkjet recording device also includes a cleaning table, and these components constitute an inkjet recording system.

[0004] The print head contains a print nozzle that ejects ink or solvent, a charging electrode that charges the particulate ink (ink particles) ejected from the print nozzle, and a deflection electrode that deflects the flight direction (travel direction) of the ink charged by the charging electrode, and is configured to eject the ink deflected by the deflection electrode to the outside to perform printing. Ink particles not used for printing are collected from the gutter of the print head.

[0005] The controller also includes an ink supply unit that includes an ink supply path for supplying ink to the print nozzles, and a control unit that controls each unit.

[0006] When the inkjet recording device of Patent Document 1 transitions from a state in which the ink circulation has stopped to an operating state, a start-up process is executed in which the ink supply unit is controlled to eject pressurized ink from the print nozzles to make the device ready for printing. During this start-up process, the print head is placed on a cleaning stand, and cleaning liquid is sprayed toward the print nozzles from cleaning nozzles provided separately from the print nozzles in the print head, automatically cleaning the print nozzles and their surroundings, thereby removing solid ink particles adhering to the print nozzle holes and gutter openings. During cleaning, cleaning liquid leaks out of the print head, but this leaked cleaning liquid is collected on the cleaning stand. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2015-136934 A Summary of the Invention [Problem to be solved by the invention]

[0008] Incidentally, there are cases where a site where printing is performed has multiple inkjet recording devices installed, such as a first inkjet recording device, a second inkjet recording device, etc. Since each inkjet recording device has a print head, a controller, and a cleaning table, there are a first print head, a second print head, etc. as print heads, a first controller, a second controller, etc. as controllers, and a first cleaning table, a second cleaning table, etc. as cleaning tables.

[0009] In such a situation, there is a possibility that automatic cleaning of the print head may be performed by mistake. That is, if a user intends to place a first print head connected to a first controller on the first cleaning stand to clean it, but mistakenly places a second print head connected to a second controller on the first cleaning stand, the first print head may not be placed on the cleaning stand. If automatic cleaning is performed in this state, there is nothing to receive the cleaning liquid leaking from the first print head, and the cleaning liquid may contaminate the surrounding environment or evaporate, creating an undesirable environment.

[0010] The present invention has been made in consideration of these points, and its object is to prevent contamination of the surrounding environment by cleaning liquid by preventing print heads that are not placed on the cleaning platform from being cleaned. [Means for solving the problem]

[0011] In order to achieve the above object, a first aspect of the present disclosure provides a print head that houses a nozzle for ejecting ink, a charging electrode for charging particulate ink ejected from the nozzle, and a deflection electrode for deflecting the flying direction of the ink charged by the charging electrode, and ejects the ink deflected by the deflection electrode to the outside, and a controller having an ink supply unit connected to the print head and supplying ink to the print head, a solvent supply unit connected to the print head and supplying solvent to the print head, and a control unit that controls the supply of ink from the ink supply unit to the print head and controls the supply of solvent from the solvent supply unit to the print head. and a cleaning placement unit that is arranged at a location different from the installation location of the print head when printing is performed by the inkjet recording device, and on which the print head is placed when cleaning the print head with solvent supplied from the solvent supply unit, wherein the inkjet recording system is characterized in that it further comprises a placement detection unit that is configured to detect that the print head has been placed on the cleaning placement unit, and that, when it detects that the print head has been placed, sends a signal based on confirmation of placement of the print head to the control unit that is connected to the print head placed on the cleaning placement unit.

[0012] According to this configuration, when the print head is placed on the cleaning platform, the placement detection unit detects that the print head has been placed. When the placement detection unit detects that the print head has been placed, a signal based on confirmation of placement of the print head is sent to a control unit connected to the print head placed on the cleaning platform. This allows the control unit to confirm that the print head connected to it is placed on the cleaning platform, and therefore determines that the print head is in a state in which it can be cleaned. Therefore, the print head placed on the cleaning platform can be cleaned, and the cleaning platform can receive any solvent leaking from the print head, preventing contamination of the surrounding environment.

[0013] Here, assuming a site where multiple inkjet recording devices, i.e., a first inkjet recording device and a second inkjet recording device, are installed, it is conceivable that, while intending to clean the first print head connected to the first controller, in reality the second print head connected to the second controller is placed on the first cleaning placement section. In this case, since the first print head is not placed on the first cleaning placement section, a signal based on confirmation of placement of the first print head is not sent to the control section of the first controller. As a result, the first controller can determine that the first print head connected to itself is not placed on the cleaning placement section, and therefore can prevent the first print head from being cleaned and the cleaning liquid from leaking from the first print head.

[0014] The placement detection unit may be provided in the print head or in the cleaning placement unit. The signal based on confirmation of placement of the print head may be a signal indicating that the print head has been placed on the cleaning placement unit, or may be a signal indicating that the placed print head is connected to the controller. The determination of whether the print head is placed on the cleaning placement unit may be performed by the controller.

[0015] The placement detection section can also be constructed from various sensors, or it can be constructed from detection means such as contacts or electrical terminals provided on the print head and cleaning placement section, respectively, so that electricity is supplied only when the print head is placed on the cleaning placement section; in this case, it can be detected that the print head has been placed on the cleaning placement section by the passage of electricity between the contacts.

[0016] A second aspect of the present disclosure is characterized in that the controller includes a cleaning operation unit that performs a cleaning operation of the print head placed on the cleaning placement unit when the control unit receives a signal based on confirmation of placement of the print head sent by the placement detection unit, and the placement detection unit sends the signal based on confirmation of placement of the print head to the control unit as an authorization signal for authorizing the cleaning operation by the cleaning operation unit.

[0017] According to this configuration, when a signal based on confirmation that the print head is placed is received, cleaning of the print head can be performed automatically.

[0018] A third aspect of the present disclosure is characterized in that the placement detection unit sends a signal based on confirmation of placement of the print head to the control unit as a disallowance signal for disallowing printing on the work by the print head and the control unit.

[0019] A fourth aspect of the present disclosure is characterized in that the cleaning operation unit is configured to prohibit cleaning operation of the print head when a signal based on confirmation of placement of the print head is not received.

[0020] In other words, not receiving a signal based on confirmation that the print head is placed on the cleaning platform means that the print head is not placed on the cleaning platform, and in this case the cleaning operation of the print head is prohibited, preventing a print head that is not placed on the cleaning platform from being mistakenly cleaned.

[0021] A fifth aspect of the present disclosure is characterized in that the placement detection unit is configured to send a signal based on confirmation of placement of the print head to the control unit via a cable connecting the print head and the controller.

[0022] With this configuration, the control signal from the controller is sent to the print head via the cable to control the print head. This cable can also be used as a means for sending a signal based on confirmation of print head placement, making it possible to simplify the system configuration.

[0023] A sixth aspect of the present disclosure is characterized in that the print head and the controller are connected by a cable, and the controller and the cleaning placement unit are connected by a wired or wireless signal line different from the cable, and the placement detection unit is configured to send a signal based on confirmation of placement of the print head to the control unit via the signal line.

[0024] A seventh aspect of the present disclosure is characterized in that the controller and the cleaning platform are connected by a wired or wireless signal line capable of transmitting identification information held by the controller to the cleaning platform, and configured to send a signal based on confirmation of placement of the print head and identification information of the controller previously obtained via the signal line to the control unit.

[0025] According to this configuration, the identification information of the controller can be obtained in advance. By sending this identification information of the controller to the control unit, the control unit can determine whether the sent identification information matches its own identification information, and if they match, it can determine that the print head is connected to itself, and if they do not match, it can determine that the print head is not connected to itself. This makes it possible to more accurately determine whether or not to perform the cleaning operation.

[0026] The identification information held by the controller can be information unique to the controller, such as the controller's serial number, and can be composed of, for example, numbers, letters, symbols, etc., and may be composed of any one of numbers, letters, symbols, etc., or a combination of any two or more of them. The controller identification information and the signal based on confirmation of print head placement may be sent simultaneously, or may be sent at different times.

[0027] An eighth aspect of the present disclosure is configured to send a signal based on confirmation of placement of the print head and identification information of the controller to the control unit via the signal line.

[0028] According to this configuration, a signal based on confirmation of head placement and the controller identification information can be sent to the control unit using a signal line for acquiring the controller identification information, thereby simplifying the system configuration.

[0029] A ninth aspect of the present disclosure is configured to obtain identification information of the print head placed on the cleaning placement section, and when sending a signal based on confirmation of the placement of the print head, also send the identification information of the print head to the control section.

[0030] With this configuration, identification information of the print head placed on the cleaning mount is sent to the control unit, making it possible to determine whether the print head and controller are connected to each other, thereby enabling a more accurate determination of whether or not a cleaning operation can be performed.

[0031] The identification information held by the print head can be information unique to the print head, such as the print head's serial number, and can be composed of, for example, numbers, letters, symbols, etc., and may be composed of any one of numbers, letters, symbols, etc., or a combination of any two or more of them. The print head identification information and the signal based on confirmation of print head placement may be sent simultaneously, or may be sent at different times.

[0032] A tenth aspect of the present disclosure is configured such that the control unit and the cleaning platform are communicatively connected, the cleaning platform and the print head are communicatively connected, and the print head and the control unit are communicatively connected, the control unit transmits authentication information to the cleaning platform, the cleaning platform transmits the authentication information transmitted from the control unit to the print head, the print head transmits the authentication information transmitted from the cleaning platform to the control unit, and the control unit is configured to perform authentication processing to determine whether or not the print head is connected to the control unit based on the authentication information transmitted to the cleaning platform and the authentication information received from the print head.

[0033] According to this configuration, if the controller, cleaning platform, and print head are a valid combination, the authentication information sent by the controller is sent to the control unit via the cleaning platform and print head, and the print head is authenticated as being connected to the controller in the authentication process. On the other hand, if the combination is not valid, the authentication information may not be received at all, and in the authentication process, a discrepancy may occur between the authentication information sent by the control unit and the authentication information received from the print head. This makes it possible to determine that the combination is not valid, and therefore makes it possible to more accurately determine whether or not the cleaning operation can be performed.

[0034] The authentication information may be, for example, the serial number of the controller, a random number, or date and time information. Effect of the Invention

[0035] As described above, according to the inkjet recording system, it is possible to prevent print heads that are not placed on the cleaning mount from being cleaned, thereby making it possible to prevent contamination of the surrounding environment by solvents. [Brief description of the drawings]

[0036] [Figure 1] FIG. 1 is a diagram illustrating an example of the overall configuration of an inkjet recording system. [Diagram 2] FIG. 2 is a block diagram illustrating a schematic configuration of the inkjet recording apparatus. [Diagram 3] FIG. 3 is a diagram illustrating a schematic configuration of a print head. [Figure 4] FIG. 4 is a diagram illustrating an example of the paths of ink and solvent in an inkjet recording apparatus. [Diagram 5] FIG. 5 is a perspective view of the print head as seen from below. [Figure 6] FIG. 6 is a flow chart illustrating the basic operation of the inkjet recording apparatus. [Figure 7]FIG. 7 is a flowchart illustrating the start-up process of the inkjet recording apparatus. [Figure 8] FIG. 8 is a diagram for explaining step A in the start-up treatment. [Figure 9] FIG. 9 is a diagram for explaining step B in the start-up treatment. [Figure 10] FIG. 10 is a diagram for explaining step C in the start-up treatment. [Figure 11] FIG. 11 is a flow chart illustrating a shutdown process of the inkjet recording apparatus. [Figure 12] FIG. 12 is a diagram for explaining step D in the cool-down treatment. [Figure 13] FIG. 13 is a diagram for explaining step E in the cool-down treatment. [Figure 14] FIG. 14 is a diagram for explaining step F in the cool-down treatment. [Figure 15] FIG. 15 is a perspective view showing the print head placed on the cleaning platform. [Figure 16] FIG. 16 is a perspective view of the cleaning platform. [Figure 17] FIG. 17 is an enlarged view of the upper part of the cleaning platform. [Figure 18] FIG. 18 is an enlarged view of the rear surface of the print head. [Figure 19] FIG. 19 is a vertical cross-sectional view showing a portion of the cleaning platform and the print head seated in the correct position. [Figure 20] FIG. 20 is a simplified block diagram of the controller, print head, and cleaning station. [Figure 21] FIG. 21 is a view corresponding to FIG. 15, illustrating another method for discharging the cleaning liquid received in the cleaning placement section. [Figure 22] FIG. 22 is a perspective view of the cleaning mount part, showing a state before the collection container is held by the holding part. [Diagram 23] FIG. 23 is a perspective view of the cleaning platform from the rear side, showing the state before the collection container is raised. [Figure 24] FIG. 24 is a vertical cross-sectional view of the state shown in FIG. [Diagram 25] FIG. 25 is a plan view of the cleaning platform. [Figure 26] FIG. 26 is a vertical cross-sectional view of the collection container attached. [Figure 27] FIG. 27 is a cross-sectional view of the collection container when it is full. [Figure 28] FIG. 28 is a flowchart illustrating the maintenance execution process. [Figure 29] FIG. 29 is a diagram for explaining a case where, at a site where multiple automatic printing systems have been installed, the print head is placed on the cleaning placement section of another system. [Diagram 30] FIG. 30 is a flowchart illustrating a process for checking the connection of a print head. [Diagram 31] FIG. 31 is a flowchart illustrating a process for checking whether or not maintenance can be performed. [Diagram 32] FIG. 32 is a view corresponding to FIG. 20 according to the first modified example. [Diagram 33] FIG. 33 is a view corresponding to FIG. 30 according to the first modified example. [Diagram 34] FIG. 34 is a view according to the second modification, which corresponds to FIG. [Diagram 35] FIG. 35 is a view corresponding to FIG. 30 according to the second modification. [Diagram 36] FIG. 36 is a view corresponding to FIG. 20 according to the third modified example. [Figure 37] FIG. 37 is a view corresponding to FIG. 30 according to the third modified example. [Figure 38] FIG. 38 is a view corresponding to FIG. 20 according to the fourth modified example. [Figure 39] FIG. 39 is a view corresponding to FIG. 30 according to the fourth modified example. [Diagram 40] FIG. 40 is a view corresponding to FIG. 20 according to the fifth modified example. [Diagram 41] FIG. 41 is a view corresponding to FIG. 30 according to the fifth modified example. [Diagram 42] FIG. 42 is a flowchart showing an example of the operation in the sleep mode. [Diagram 43]FIG. 43 is a diagram showing an example of a maintenance user interface. [Diagram 44] FIG. 44 is a diagram showing an example of a status display user interface. [Diagram 45] FIG. 45 is a flow chart for operating the sleep mode while checking for abnormalities on the cleaning placement unit side. [Figure 46] FIG. 46 is a timing chart showing a case where an abnormality is detected during start-up processing. [Figure 47] FIG. 47 is a diagram corresponding to FIG. 45, showing a process according to a modified example of the sleep mode. [Figure 48] FIG. 48 is a diagram showing an example of a period selection user interface displayed at the time of shutdown. [Figure 49] FIG. 49 is a flowchart showing an example of the sleep mode transition determination process. [Figure 50] FIG. 50 is a flowchart showing an example of the automatic sleep mode transition determination process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. Note that the following description of the preferred embodiments is merely illustrative in nature and is not intended to limit the present invention, its applications, or its uses.

[0038] In other words, in this specification, an industrial inkjet printer will be described as an example of an inkjet recording device, but the technology disclosed herein can be applied to general equipment that uses an inkjet to propel ink particles to land on a workpiece, regardless of whether it is called an inkjet recording device or an industrial inkjet printer.

[0039] Furthermore, in this specification, printing by an inkjet recording device will be described, but "printing" here includes all processing using inkjet technology, such as printing characters and marking figures.

[0040] <Overall composition> FIG. 1 is a diagram illustrating an example of the overall configuration of an inkjet recording system S. FIG. 2 is a diagram illustrating a schematic configuration of an inkjet recording apparatus I, and FIG. 3 is a diagram illustrating a schematic configuration of a print head 1 in the inkjet recording apparatus I. And FIG. 4 is a diagram illustrating the paths of ink and solvent in the inkjet recording apparatus I. The automatic printing system S illustrated in FIG. 1 is installed on a conveying line L in a factory or the like, for example, and is configured to print on each work W flowing along the conveying line L in order. Note that the application of the present disclosure is not limited to the automatic printing system S. It can also be applied to a printing system using a method other than automatic. The conveying line L can be configured, for example, by a belt conveyor.

[0041] Specifically, the automatic printing system S includes an inkjet recording device I that performs printing by causing particulate ink (ink grains) to land on a workpiece W, an operation terminal 800 and an external device 900 that are connected to the inkjet recording device I, and a cleaning placement unit 200 that is connected to the inkjet recording device I and cleans the print head 1. Note that the operation terminal 800 and the external device 900 are not essential.

[0042] The inkjet recording device I illustrated in Figures 1 to 3 includes a print head 1 that ejects ink droplets from a nozzle 12 and causes the ink droplets to land on a workpiece W, and a controller 100 that supplies a control signal, ink, and solvent to the print head 1. The controller 100 supplies a control signal to the print head 1, thereby controlling the trajectory of the ink droplets. This adjusts the landing position of the ink droplets on the workpiece W, thereby achieving the desired printing.

[0043] In particular, the inkjet recording apparatus I according to this embodiment is configured as a so-called continuous ink jet printer (CIJ). That is, in order to prevent clogging (particularly clogging of the nozzles 12) caused by the volatilization of ink, ink is constantly circulating inside the inkjet recording apparatus I even when printing is not being performed, as long as the inkjet recording apparatus I is in operation. By employing the continuous method, it becomes possible to use quick-drying ink without inviting clogging due to ink.

[0044] Furthermore, the inkjet recording apparatus I according to this embodiment is capable of cleaning each part of the print head 1, such as the nozzles 12, by sending a solvent to the print head 1. The solvent used for cleaning can be recovered as necessary and reused to adjust the concentration (viscosity) of the ink.

[0045] To achieve ink circulation, the print head 1 is equipped with nozzles 12 that eject ink or solvent, as well as a gutter 16 that collects the ink or solvent ejected from the nozzles 12 (see FIG. 3). The ink or solvent sent from the controller 100 to the print head 1 is ejected from the nozzles 12 and collected by the gutter 16. The ink or solvent thus collected is sent back to the controller 100 and reused. By repeating these steps, the ink can be circulated.

[0046] The operation terminal 800 has, for example, a central processing unit (CPU) and a storage device, and is connected to the controller 100. This operation terminal 800 functions as a terminal for setting processing conditions for printing and for displaying information related to printing to the user.

[0047] The processing conditions set by the operation terminal 800 are output to the controller 100 and stored in its storage unit 102. In addition to the storage unit 102 of the controller 100, or instead of the storage unit 102, the operation terminal 800 may store the processing conditions.

[0048] The processing conditions according to this embodiment include the contents of the character string to be printed, as well as conditions and parameters related to the start-up process (hereinafter, also referred to as "cleaning settings"), which will be described later.

[0049] The operation terminal 800 can be integrated into the controller 100, for example. In this case, the term "operation terminal" is not used, but rather a term such as a control unit is used.

[0050] The external device 900 is connected to the controller 100 as necessary. In the example shown in Figures 1 and 2, a work detection sensor 901, a conveying speed sensor 902, and a programmable logic controller (PLC) 903 are provided as the external device 900.

[0051] Specifically, the workpiece detection sensor 901 detects the presence or absence of the workpiece W on the conveying 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 (printing trigger) for starting printing.

[0052] The conveying speed sensor 902 is composed of, for example, a rotary encoder, and can detect the conveying speed of the workpiece W. The conveying speed sensor 902 outputs a signal (detection signal) indicating the detection result to the controller 100. The controller 100 controls the timing of ejecting ink particles from the print head 1 based on the detection signal input from the conveying speed sensor 902.

[0053] 2, the PLC 903 is electrically connected to the controller 100. The PLC 903 is used to control the inkjet recording system S in accordance with a predetermined sequence.

[0054] In addition to the above-mentioned devices and apparatuses, the inkjet recording apparatus I can also be connected to a device for performing operation and control, a computer for performing various other processes, a storage device, peripheral devices, and the like. In this case, the connection may be, for example, a serial connection such as IEEE1394, RS-232, RS-422, and USB, or a parallel connection. Alternatively, an electrical, magnetic, or optical connection may be adopted via a network such as 10BASE-T, 100BASE-TX, or 1000BASE-T. In addition to a wired connection, a wireless connection using a wireless LAN such as IEEE802, or radio waves, infrared rays, optical communication, and the like such as Bluetooth (registered trademark) may also be adopted. Furthermore, as a storage medium used in a storage device for exchanging data and saving various settings, for example, various memory cards, magnetic disks, magneto-optical disks, semiconductor memories, hard disks, and the like can be used.

[0055] <Controller 100> The controller 100 is configured to electrically control the print head 1 and to be able to supply the print head 1 with ink for printing and a solvent for diluting the ink.

[0056] Specifically, the controller 100 of this embodiment includes, as components related to electrical control, a memory unit 102 that stores the above-mentioned processing conditions, a control unit 101 that controls each part of the controller 100 and the print head 1, an operation display unit 103 that accepts operations by the user and displays information to the user, and a power supply unit 121 that directs power supplied from outside to the control unit 101.

[0057] The controller 100 also includes components related to the supply of ink, etc., such as an ink supply unit 104 that supplies ink to the nozzles 12 of the print head 1, and a solvent supply unit 105 that supplies solvent to the nozzles 12 and the ink supply unit 104.

[0058] The control unit 101 may be configured as a separate unit from the ink supply unit 104 and the solvent supply unit 105. 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, the components can be combined to form the controller 100.

[0059] (Storage unit 102) The memory unit 102 is configured to store processing conditions set via the operation display unit 103 described below or the operation terminal 800, and to output the stored processing conditions to the control unit 101 based on a control signal from outside.

[0060] Specifically, the storage unit 102 is configured using a volatile memory, a non-volatile memory, a hard disk drive (HDD), a solid state drive (SSD), etc., and can temporarily or continuously store information indicating processing conditions. When the operation terminal 800 is incorporated in the controller 100, the operation terminal 800 may also function as the storage unit 102.

[0061] (Control unit 101) The control unit 101 controls at least the ink supply unit 104 and the solvent supply unit 105 in the controller 100, and the nozzle 12, the charging electrode 13, and the deflection electrode 15 in the print head 1, based on the processing conditions stored in the memory unit 102. The control unit 101 controls each unit, so that printing on the workpiece W is performed at a predetermined timing.

[0062] Specifically, the control unit 101 has, for example, a CPU, a memory, an input / output bus, etc., and generates a control signal based on a signal indicating information input via the operation display unit 103 or the operation terminal 800 and a signal indicating processing conditions read from the storage unit 102. The control unit 101 outputs the generated control signal to the controller 100 and each unit of the inkjet recording apparatus I, thereby controlling printing on the workpiece W.

[0063] For example, when printing on the workpiece W, the control unit 101 reads the contents to be printed on the workpiece W stored in the memory unit 102 and generates a control signal based on the contents to be printed. Then, the control unit 101 outputs the control signal to the charging electrode 13, thereby setting the flight direction of the ink particles so as to realize the landing position corresponding to the contents to be printed.

[0064] (Operation display section 103) 1, the operation display unit 103 can be provided in, for example, a housing constituting the controller 100, but may also be configured separately from the housing and installed in a location different from the housing. The operation display unit 103 includes a display unit 103a that displays various information related to the inkjet recording apparatus I, and an operation unit 103b that is, for example, a touch-type operation panel, buttons, switches, etc. The display unit 103a is, for example, configured as a liquid crystal display panel or an organic EL display panel, and is controlled by the control unit 101, and is configured to be able to display a user interface, etc., as described later.

[0065] When a user operates the operation unit 103b of the operation display unit 103, the operation information is input to the control unit 101, and the control unit 101 can detect what operation has been performed. For example, by operating the operation unit 103b, it is possible to switch the power of the inkjet recording apparatus I on / off, perform various settings, input information, and the like. Note that, when the operation terminal 800 is incorporated in the controller 100, the operation terminal 800 may also function as the operation display unit 103. The display unit 103a of the operation display unit 103 is a notification unit that notifies the user of various information, and the operation unit 103b is an input unit that allows various information to be input.

[0066] This operation and display unit 103 can also set processing conditions for printing, similar to the above-mentioned operation terminal 800. The processing conditions set by the operation and display unit 103 are output to the controller 100 and stored in its memory unit 102. In the following description, it is assumed that the user operates the operation and display unit 103, but the operation terminal 800 can also be used in place of the operation and display unit 103.

[0067] (Ink supply unit 104) The ink supply unit 104 has, as its main components, an ink cartridge 104a that contains refill ink, a main tank 104b to which ink is supplied from the ink cartridge 104a, and an ink flow path 104c. The ink cartridge 104a, the main tank 104b, and the print head 1 are fluidly connected via the ink flow path 104c.

[0068] Of these, the ink cartridge 104a is configured to be detachable from the controller 100, and by replacing it, the main tank 104b can be replenished with ink.

[0069] In this way, the inkjet recording apparatus I according to this embodiment is configured as a so-called "cartridge type" inkjet printer, but is not limited to this configuration. For example, it may be configured to have a tank that can be opened and closed manually, and to refill the tank with ink.

[0070] The main tank 104b is a container that stores ink to be supplied to the nozzles 12, and is specifically configured to store ink whose concentration (viscosity) is adjusted by a solvent. To realize such a configuration, a solvent supply path is connected to the path from the ink cartridge 104a to the main tank 104b.

[0071] Furthermore, the ink flow path 104c is a path for supplying ink to the print head 1, and includes, for example, a path for sending ink to the nozzles 12, and a path for sending ink back from the gutter 16. The path for sending ink to the nozzles 12 connects the ink cartridge 104a, the main tank 104b, and the nozzles 12. The path for sending ink back from the gutter 16 connects the gutter 16 and the main tank 104b. Ink can be circulated between the print head 1 and the controller 100 by these paths.

[0072] As described below, the ink flow path 104c is provided with a plurality of solenoid valves including a first valve V1, and a plurality of pumps including an ink pump P1. Of these, each solenoid valve is capable of controlling the flow of ink by opening and closing in response to a control signal output from the control unit 101. Meanwhile, each pump is capable of pumping ink in response to a control signal output from the control unit 101, and of controlling the flow of ink in the same manner as the solenoid valves.

[0073] (Solvent supply unit 105) The solvent supply unit 105 has, as its main components, a solvent cartridge 105a that contains replenishment solvent, a conditioning tank 105b that stores the solvent used for cleaning, and a solvent flow path 105c. The solvent cartridge 105a, the conditioning tank 105b, and the print head 1 are fluidly connected via the solvent flow path 105c. The solvent flow path 105c through which the solvent flows is made up of multiple paths, some of which are also used as paths for returning ink from the gutter 16.

[0074] The solvent cartridge 105a is configured to be detachable from the controller 100. By replacing the solvent cartridge 105a, the controller 100 can be replenished with solvent. A solvent tank may be provided instead of the solvent cartridge 105a. The solvent supply unit 105 has a function of detecting whether the solvent in the solvent cartridge 105a has run out or whether there is little solvent remaining. The solvent contained in the solvent cartridge 105a is used to adjust the concentration of the ink, and is also used as a cleaning agent for cleaning the paths through which the ink flows.

[0075] The conditioning tank 105b is configured to store the solvent used for cleaning. As described above, the solvent discharged from the nozzles 12 is collected by the gutter 16 in the same manner as the ink. Therefore, the path for returning the ink from the gutter 16 also serves as the path for returning the solvent.

[0076] The solvent flow path 105c also includes paths for supplying the solvent to the print head 1, the main tank 104b, etc., and has, for example, a path for feeding the solvent to the nozzle 12, and a path for feeding the solvent back from the gutter 16. The path for feeding the solvent to the nozzle 12 connects the solvent cartridge 105a and the nozzle 12. As described above, the path for feeding the solvent back from the gutter 16 also serves as a path for feeding the ink back.

[0077] As described below, the solvent flow path 105c is provided with a plurality of solenoid valves including a sixteenth valve V16, and a plurality of pumps including a solvent pump P2. Of these, each solenoid valve is opened and closed in response to a control signal output from the control unit 101, and is capable of controlling the flow of the solvent. Meanwhile, each pump is configured to pump the solvent in response to a control signal output from the control unit 101, and is capable of controlling the flow of the solvent in the same manner as the solenoid valves.

[0078] The classification of the solvent flow path 105c and the ink flow path 104c described above is merely a convenient classification made for the sake of simplicity of explanation. The solvent flow path 105c and the ink flow path 104c are substantially inseparable because they are connected to each other or one serves the other.

[0079] (Power supply section 121) The power supply unit 121 is interposed between the commercial power source 700 and the control unit 101, and is capable of relaying power supplied from the commercial power source 700 and supplying it to the control unit 101.

[0080] (Other components) The controller 100 is provided with a connection cable 107 which is a bundle of covered electrical wiring for sending and receiving control signals, tubes for sending and receiving ink (specifically, tubes defining the ink flow path 104c), and tubes for sending and receiving solvent (specifically, tubes defining the solvent flow path 105c). This connection cable 107 is flexible, and is connected to the upper end of the print head 1 (see FIG. 1). The controller 100 and the print head 1 are electrically and fluidly connected via this connection cable 107.

[0081] <Print head 1> The print head 1 ejects ink as particulate ink droplets, the concentration of which has been adjusted based on the ink and solvent, and a control signal supplied from the controller 100. The print head 1 deflects the flight direction of the ejected ink droplets, and causes the deflected ink droplets to land on the surface of the workpiece W, thereby executing printing on the workpiece W.

[0082] Specifically, as shown in FIG. 3, the print head 1 of this embodiment includes a vibrator 11 that vibrates the ink, a nozzle 12 that ejects the ink vibrated by the vibrator 11, a charging electrode 13 that charges the particulate ink ejected from the nozzle 12, a charge detection sensor 14 that monitors the charged state of the ink, a deflection electrode 15 that deflects the flight direction of the ink charged by the charging electrode 13, and a gutter 16 that collects the ink that has been undeflected by the deflection electrode 15 or the solvent ejected from the nozzle 12.

[0083] The print head 1 includes a housing 10 that accommodates a vibrator 11, a nozzle 12, a charging electrode 13, a charge detection sensor 14, a deflection electrode 15, and a gutter 16, and defines a flight space S1 for the ink droplets. This print head 1 can eject the ink droplets deflected by the deflection electrode 15 to the outside of the housing 10 through the flight space S1.

[0084] 5, an ejection port A is opened on the bottom surface of the housing 10 that forms the outer shape of the print head 1, for ejecting ink deflected by the deflection electrode 15 to the outside. The ink is ejected from the ejection port A toward the bottom of the housing 10.

[0085] As shown in Fig. 1, during printing, print head 1 is supported, for example, by a support member 2. When print head 1 is supported by support member 2, it is positioned so that its ejection holes A face from above the printing surface of workpiece W. This is an example of a location where print head 1 is installed when printing is performed by inkjet recording device I.

[0086] Below, each part of the print head 1 will be explained in order. In the following description, the "upward direction" refers to the direction along the vertical direction. For example, the upper side of the paper in Fig. 3 corresponds to the "upward direction", and the lower side of the paper in the same figure corresponds to the "downward direction". In other figures, the corresponding direction is also called the "upward direction".

[0087] (Vibrator 11) 3, the vibrator 11 is disposed near the upper end of the flight space S1 of the housing 10. The vibrator 11 according to this embodiment has a built-in device (e.g., a piezoelectric element) for applying vertical vibrations (exciting) to the ink. The vibrator 11 is configured so that ink is supplied via a connection cable 107, and is capable of vibrating the ink thus supplied. The ink vibrated by the vibrator 11 is supplied to the nozzle 12.

[0088] Although not shown in the figure, the vibrator 11 according to this embodiment is grounded.

[0089] (Nozzle 12) As shown in Fig. 3, the nozzle 12 is connected to the lower end of the vibrator 11, and is disposed with its open end (ink ejection port) facing downward. Ink vibrated by the vibrator 11 can be ejected from the open end of the nozzle 12. A suction path 27 that functions as a return path for releasing pressure inside the print head 1 during start-up, for example, is connected to the nozzle 12 (see Fig. 4). In addition, a solvent can be sucked from the nozzle 12 through the suction path 27.

[0090] Here, the ink discharged from the nozzle 12 without being vibrated by the vibrator 11 flows as an axial so-called "ink axis." On the other hand, the vibrated ink is atomized immediately after being discharged from the nozzle 12, becoming so-called "ink particles." The ink discharged from the nozzle 12 is axially shaped immediately after being discharged from the nozzle 12, but becomes particle-shaped as it moves away from the nozzle 12. The position where the ink becomes particle-shaped is called the breakpoint. The ink discharged from the nozzle 12 (ink particles) passes through the charging electrode 13, which will be described later.

[0091] The solvent supplied to clean the print head 1 passes through the vibrator 11 and the nozzle 12 in that order, and is discharged from the tip of the nozzle 12. The discharged solvent flows axially and passes through the charged electrode 13.

[0092] (Charged electrode 13) 3, the charging electrode 13 is composed of a pair of conductive metal plates, and is disposed below the nozzle 12. Here, the pair of metal plates constituting the charging electrode 13 are fixed to the housing 10 in a position in which their respective longitudinal directions are aligned in the up-down direction and in a position in which they face each other in the horizontal direction. The distance between the pair of metal plates is set to be larger than the particle diameter of the ink ejected from the nozzle 12, so that the ink ejected from the nozzle 12 passes between the pair of metal plates.

[0093] A potential (positive potential) is applied to the charging electrode 13 according to this embodiment at least when a printing operation is performed. This generates a potential difference between the vibrator 11 and the charging electrode 13, making it possible to charge the ink droplets passing through the charging electrode 13. In order to charge each ink droplet, the charging electrode 13 according to this embodiment is disposed near a breakpoint where the ink ejected from the nozzle 12 breaks into particles.

[0094] A pulse potential that can be controlled by the controller 100 is applied to the charging electrode 13. When a relatively high voltage is applied to the charging electrode 13, the charge amount (magnitude of negative charge) of each ink particle is larger than when a lower voltage is applied. When the charge amount of each ink particle is large, it is deflected by the deflection electrode 15 to a greater extent than when the charge amount is small. The controller 100 adjusts the magnitude of the pulse potential to control the deflection amount of the ink particle. The ink particle charged by the charging electrode 13 reaches the deflection electrode 15 after passing by the side of the charge detection sensor 14.

[0095] Moreover, the solvent discharged from the nozzle 12 passes beside the charge detection sensor 14 and reaches the deflection electrode 15 without being charged.

[0096] (Charge detection sensor 14) 3, the charge detection sensor 14 is disposed below the charging electrode 13. More specifically, the charge detection sensor 14 is disposed below the metal plate (the metal plate on the right side of the paper in the example shown in FIG. 3) constituting the charging electrode 13 so as not to intersect with the trajectory of the flying ink particle. By disposing the charge detection sensor 14 in this manner, it is possible to avoid collision between the ink particle and the charge detection sensor 14.

[0097] Moreover, 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 particles passing by its side. The detection result by 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 or not each ink particle is appropriately charged.

[0098] (Deflection electrode 15) 3, the deflection electrode 15 is composed of a pair of conductive metal plates (so-called "counter electrodes"), and is disposed 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 in which their respective longitudinal directions are aligned substantially in the vertical direction and in a position in which they face each other in the horizontal direction. The ink particles that pass between the pair of metal plates that constitute the charging electrode 13 pass between the pair of metal plates that constitute the deflection electrode 15.

[0099] A voltage that can be controlled by the controller 100 is applied to the deflection electrode 15. This generates a potential difference between the pair of metal plates that make up the deflection electrode 15. This potential difference makes it possible to deflect the flight direction of an ink particle according to the charge of the ink particle. The flight direction of the ink particle can be deflected along the arrangement direction of the pair of metal plates that make up the deflection electrode 15.

[0100] That is, the flight direction of the ink particles can be controlled via the voltages applied to the charged electrode 13 and the deflection electrode 15, respectively. The ink particles 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 (non-deflected). Of these, the ink particles deflected by the deflection electrode 15 participate in printing on the workpiece W. The ink particles deflected by the deflection electrode 15 are ejected from the ejection port A provided on the bottom surface of the housing 10, and land on the workpiece W.

[0101] On the other hand, ink particles that are not deflected by the deflection electrode 15 do not participate in printing on the workpiece W. Such ink particles, or axial ink that is not particulated in the first place, reach the inside of the gutter 16, as shown by the dashed line in Fig. 3. Similarly, the solvent used to wash the nozzles 12, etc. in the print head 1 and that has passed through the deflection electrode 15 also reaches the inside of the gutter 16.

[0102] (Gutter 16) 3, the gutter 16 is configured by a curved tube with its open end facing upward, and is disposed below the deflection electrode 15. The gutter 16 according to this embodiment can collect ink that is not involved in printing on the workpiece W and the solvent that has passed through the nozzle 12 (specifically, the solvent ejected from the nozzle 12).

[0103] More specifically, in this embodiment, the open end (upstream end) of the gutter 16 and the open end of the nozzle 12 are disposed to face each other, and the open end of the nozzle 12 is located directly above the open end of the gutter 16. By disposing them in this manner, it becomes possible for the fluid that flows vertically from the open end of the nozzle 12 to be received from the open end of the gutter 16.

[0104] The ink or solvent collected by the gutter 16 is returned to the controller 100 via the ink flow path 104c, the solvent flow path 105c, etc., and is stored in the main tank 104b or the conditioning tank 105b.

[0105] In the following, in order to provide a detailed explanation of the recovery of ink or solvent by the gutter 16, the configuration of the ink flow path 104c and the solvent flow path 105c will be described with reference to Fig. 4. Note that the component marked with the reference symbol F in Fig. 4 is an example of a filter. In the following description, a description of the arrangement, configuration, etc. of the filter F will be omitted.

[0106] <Ink and solvent routes> As described above, the controller 100 according to this embodiment includes an ink flow path 104c for supplying ink to the print head 1, and a solvent flow path 105c for supplying solvent to the print head 1 and the main tank 104b, etc.

[0107] Specifically, the ink flow path 104c has, as paths related to the supply of ink to the nozzle 12, a first ink path 21 connecting the ink cartridge 104a and the first branch portion 51, a sixth ink path 26 connecting the first branch portion 51 (more specifically, a midway portion of the second ink path 22) and the second branch portion 52, an eighth ink path 28 connecting the second branch portion 52 and the main tank 104b, and a fourth ink path 24 connecting the main tank 104b and the nozzle 12. Here, the sixth ink path 26 according to this embodiment is connected to the second branch portion 52 via a fifth ink path 25 described later.

[0108] In addition, the ink flow path 104c has, as a path related to viscosity measurement by the viscometer 53, a second ink path 22 that connects the first branch portion 51 and the main tank 104b and has the viscometer 53 interposed therein, and a third ink path 23 that is provided independently of the second ink path 22 and connects the main tank 104b and the first branch portion 51.

[0109] Furthermore, the ink flow path 104c has a fifth ink path 25, which is a path related to the recovery of ink by the gutter 16, connecting the gutter 16 and the main tank 104b.

[0110] Here, the second ink path 22 is provided with, in that order, a circulation pump P4, an eleventh valve V11, and a viscometer 53. The fourth ink path 24 is provided with, in that order, an ink pump P1, a pressure reducing valve, a pressure gauge, and a fourteenth valve V14. The fifth ink path 25 is provided with, in that order, a tenth valve V10, a gutter pump P3, and a second branch section 52.

[0111] On the other hand, the solvent flow path 105c has a first solvent path 31 that connects the solvent cartridge 105a and the nozzle 12 as a path related to the supply of the solvent to the nozzle 12.

[0112] In addition, the solvent flow path 105c may have a second solvent path 32 connecting a midpoint in the first solvent path 31 and the first branch portion 51 as a path related to adjusting the concentration (viscosity) of the ink using the solvent contained in the solvent cartridge 105a (a part of the path connecting the solvent cartridge 105a and the main tank 104b).

[0113] In addition, the solvent flow path 105c may have a third solvent path 33 connecting the first branch portion 51 and the conditioning tank 105b as a path related to concentration adjustment using the solvent stored in the conditioning tank 105b (a part of the path connecting the main tank 104b and the conditioning tank 105b).

[0114] It should be noted that the fifth ink path 25 exemplified as the ink flow path 104c is related to the recovery of the solvent by the gutter 16. As described above, the classification of "ink flow path 104c" and "solvent flow path 105c" is merely a classification for convenience.

[0115] Here, the first solvent path 31 is provided in this order with an optical empty detection mechanism 44, a solvent pump P2, a sixteenth valve V16, and a twelfth valve V12. A cleaning nozzle 19 is connected to the first solvent path 31 as a solvent spraying unit. The cleaning nozzle 19 is a nozzle for spraying a solvent onto the vibrator 11, the tip of the nozzle 12, the charging electrode 13, the deflection electrode 15, etc. in the print head 1 to clean them, and can spray a solvent as a cleaning liquid. A fifteenth valve V15 is provided on the way from the cleaning nozzle 19 to the first solvent path 31.

[0116] Here, the first branch section 51 has a fifth valve V5 that opens and closes between the third ink path 23 and the second ink path 22, an eighth valve V8 that opens and closes between the first ink path 21 and the second ink path 22, a ninth valve V9 that opens and closes between the third solvent path 33 and the second ink path 22, and a thirteenth valve V13 that opens and closes between the second solvent path 32 and the second ink path.

[0117] The second branch section 52 also has a first valve V1 that opens and closes between the sixth ink path 26 and the eighth ink path 28, a third valve V3 that opens and closes between the sixth ink path 26 and the conditioning tank 105b, and a fourth valve V4 that opens and closes between the sixth ink path 26 and the waste liquid tank (shown as "waste liquid" in Figure 4).

[0118] The control unit 101 can configure a desired flow path within the controller 100 by outputting control signals to valves provided in each path, such as the eleventh valve V11, and by outputting control signals to each valve constituting the first branch section 51 and the second branch section 52.

[0119] For example, by opening the eighth valve V8 and the first valve V1, it becomes possible to refill the main tank 104b with ink from the ink cartridge 104a. Also, although this is not an original circulation operation, by opening the fifth valve V5 and the eleventh valve V11, it becomes possible to circulate ink between the second ink path 22, the main tank, and the third ink path 23, and to measure the viscosity of the ink with the viscometer 53.

[0120] The same is true for paths related to the solvent. For example, by opening the thirteenth valve V13 and the first valve V1, the solvent contained in the solvent cartridge 105a is supplied to the main tank 104b, and the concentration of the ink stored in the tank can be adjusted. Also, by opening the ninth valve V9 and the first valve V1, the solvent mixed with ink stored in the conditioning tank 105b passes through the third solvent path 33, the first branch 51, the sixth ink path 26, the second branch 52, and the eighth ink path 28 and is supplied to the main tank 105a.

[0121] The controller 100 also has paths related to air circulation. For example, a first exhaust pipe 41 leading to an exhaust port (not shown) is connected to the main tank 104b. Similarly, a second exhaust pipe 42 leading to the exhaust port is connected to the conditioning tank 105b.

[0122] As another example of a path related to air circulation, the controller 100 has a suction path 27 that connects the nozzle 12 and the first branch portion 51. A sixth valve V6 is provided in the suction path 27, and by opening this sixth valve V6 and the above-mentioned fifth valve V5, the nozzle 12 can be communicated with the atmosphere via the suction path 27, the first branch portion 51, the sixth ink path 26, the second branch portion 52, the eighth ink path 28, the main tank 104b, and the first exhaust pipe 41. This makes it possible to adjust the ejection pressure of ink droplets ejected from the nozzle 12.

[0123] Furthermore, when printing is performed, the fourteenth valve V14 is opened to supply ink from the main tank 104b via the fourth ink path 24. The ink thus supplied is ejected from the nozzle 12 in the form of ink particles.

[0124] Here, of the ink (ink droplets) ejected from the nozzles 12, the ink involved in printing is ejected from the print head 1 as described with reference to Fig. 3. On the other hand, the ink not involved in printing and the solvent used to wash the nozzles 12 etc. are collected in the gutter 16 and sent back to the controller 100 through the fifth ink path 25.

[0125] In this case, the ink to be returned to the main tank 104b is supplied to the main tank 104b from the first branch portion 51 via the sixth ink path 26, the first valve V1 in the second branch portion 52, and the eighth ink path 28. On the other hand, the solvent to be returned to the conditioning tank 105b is supplied to the conditioning tank 105b from the fifth path 25 via the third valve V3 in the second branch portion 52.

[0126] The recovery of ink or solvent by the gutter 16 is carried out, for example, in association with the start-up process and the shut-down process of the inkjet recording apparatus I. Here, "start-up process" refers to the process executed before the start of printing when the power to the inkjet recording apparatus I is turned on. On the other hand, "shut-down process" refers to the process executed before the operation of the inkjet recording apparatus I is stopped when the power to the inkjet recording apparatus I is turned off.

[0127] More specifically, the inkjet recording apparatus I according to this embodiment does not immediately start printing even when the power switch is turned on. Before starting printing, the inkjet recording apparatus I executes a predetermined start-up process. In this start-up process, the print head 1 is cleaned using a solvent, and then ink ejection is started. The ink ejected immediately after the start-up process begins forms the ink axis described above, and is collected by the gutter 16.

[0128] Similarly, the inkjet recording apparatus I according to this embodiment does not immediately stop its operation when the power switch is turned off. Before stopping its operation, the inkjet recording apparatus I executes a predetermined shutdown process including nozzle cleaning. In this shutdown process, a solvent is ejected from the nozzle 12 to clean and recover the ink remaining therein. The ink discharged from the nozzle 12 as the solvent is ejected is recovered by the gutter 16, similar to the ink shaft in the startup process.

[0129] In this embodiment, the "power switch" includes not only a physical push button but also switches configured with a touch-type operation panel displayed on the operation display unit 103, etc. The power switch OFF operation refers to not only the operation of physically pressing a push button, etc., but also a shutdown operation instructed via the operation terminal 800, the operation display unit 103, etc. The same applies to the power switch ON operation.

[0130] The start-up process and the shut-down process of the inkjet recording apparatus I will be described in detail below.

[0131] <Basic operation of inkjet recording device I> 6 is a flowchart illustrating the basic operation of the inkjet recording apparatus I. This flowchart illustrates the basic operation of the inkjet recording apparatus I, including the start-up process.

[0132] First, in step SA1 in FIG. 6, the power switch of the inkjet recording apparatus I is turned from OFF to ON, and the inkjet recording apparatus I is powered on.

[0133] In step SA2 following step SA1, the control unit 101 executes a start-up process.

[0134] Fig. 7 is a flowchart illustrating the start-up process of the inkjet recording apparatus I. This flowchart illustrates the details of step SA2 in Fig. 6. That is, four steps SB1, SB2, SB3, and SB4 in Fig. 7 constitute step SA2 in Fig. 6.

[0135] Moreover, FIG. 8 is a diagram for explaining step A in the start-up treatment, FIG. 9 is a diagram for explaining step B in the start-up treatment, and FIG. 10 is a diagram for explaining step C in the start-up treatment.

[0136] In step SB1, the control unit 101 executes process A to increase the pressure in the ink and solvent paths in the inkjet recording apparatus I. In this process A, in order to prepare the solvent, the control unit 101 keeps the sixteenth valve V16 open and the twelfth valve V12 closed while waiting. In this state, the solvent pump P2 operates, so that the solvent contained in the solvent cartridge 105a is supplied to the vicinity of the twelfth valve V12 via the first solvent path 31 (see the thick line in FIG. 8).

[0137] Furthermore, in order to prepare the ink, the control unit 101 keeps the fourteenth valve V14 in a closed state and on standby. In this state, the ink pump P1 operates, and the ink pressure in the fourth ink path 24 increases (see the thick line in FIG. 8).

[0138] Furthermore, to prepare the gutter 16, the control unit 101 keeps the tenth valve V10 and the first valve V1 open and on standby. In this state, the gutter pump P3 operates to send the ink or solvent collected by the gutter 16 back to the main tank 104b via the fifth ink path 25 and the second branch portion 52 (see the bold line in FIG. 8).

[0139] In step A, a detection signal from the pressure gauge is input to the control unit 101. Based on the detection signal, the control unit 101 waits until the pressure in the fourth ink path 24 becomes equal to or greater than a specified value.

[0140] In step SA2, which follows step SA1, the control unit 101 executes step B and ejects the solvent from the nozzle 12. In this step B, the control unit 101 opens the twelfth valve V12, so that the solvent is sucked out and ejected from the nozzle 12. The ejected solvent is collected by the gutter 16. This step B is executed for a short period of less than one second, so a small amount of solvent is ejected compared to the other steps. Therefore, the solvent ejected in step B is sent back to the main tank 104b from the fifth ink path 25 via the first valve V1 (see the thick line in FIG. 9).

[0141] When a large amount of solvent is sprayed in the process B, the third valve V3 is opened instead of the first valve V1, and the solvent is returned from the fifth ink path 25 to the conditioning tank 105b.

[0142] In step SA3, which follows step SA2, the control unit 101 executes step C to eject ink from the nozzle 12. In this step C, in order to eject ink, the control unit 101 closes the twelfth valve V12 and opens the fourteenth valve V14. This causes ink in a shaft shape (ink shaft) to be ejected from the nozzle 12. The ejected ink is collected by the gutter 16. The collected ink is sent back to the main tank 104b from the fifth ink path 25 via the first valve V1 (see the thick line in FIG. 10).

[0143] In step SA4, which follows step SA3, the control unit 101 starts vibrating the ink ejected from the nozzle 12 and applying voltage to the charging electrode 13 and the deflection electrode 15. This makes it possible to atomize the ink, charge it, and deflect it.

[0144] When the process shown in step SA4 is completed, a return is made, and the control process shown in Fig. 7 returns to the control process shown in Fig. 6. Then, the control unit 101 executes step SA3 following step SA2.

[0145] In step SA3, the control unit 101 performs printing on the workpiece W by causing particulate ink (ink grains) to land on the workpiece W.

[0146] When the printing operation on the workpiece W is started, as shown in Fig. 3, ink vibrated by the vibrator 11 is ejected from the nozzle 12. This ink is supplied appropriately from the ink supply unit 104 of the controller 100. The ink ejected from the nozzle 12 starts to be atomized immediately after ejection, and is charged by the charging electrode 13 at the particulate stage. The ink particles charged by the charging electrode 13 pass through the deflection electrode 15 after the charged state is detected by the charge detection sensor 14.

[0147] Then, the ink particles, whose flight direction has been deflected by the deflection electrode 15, pass through a flight section S1 inside the housing 10 and are ejected outside the print head 1. The ink particles ejected from the print head 1 land on the surface of the workpiece W to form characters or figures, as shown in Figure 1. Here, the landing position of the ink particles is controlled via the charge amount of each ink particle and the voltage applied to the deflection electrode 15.

[0148] As described above, the inkjet recording apparatus I according to this embodiment is configured as a continuous type inkjet printer, so that in a printable state after start-up processing (operating state of the inkjet recording apparatus I), ink continues to be ejected from the nozzles 12 even when printing is not being performed. The ink ejected at this time is not deflected by the deflection electrode 15 (in other words, it is "non-deflected"). The non-deflected ink does not participate in printing, but is collected by the gutter 16, circulated inside the apparatus, and reused.

[0149] Here, consider the case where printing is completed smoothly and inkjet recording apparatus I is normally shut down. Specifically, assume that in step SA3, the power switch of inkjet recording apparatus I is about to be switched from ON to OFF.

[0150] In this case, in step SA4, the control unit 101 executes a fall process. This fall process is an example of a "cleaning operation" in this embodiment. The cleaning operation is executed by the cleaning operation unit 101a of the control unit 101.

[0151] Fig. 11 is a flowchart illustrating the shut-down process of the inkjet recording apparatus I. This flowchart illustrates the details of step SA4 in Fig. 6. That is, five steps SC1 to SC5 in Fig. 11 constitute step SA4 in Fig. 6.

[0152] Moreover, FIG. 12 is a diagram for explaining step D in the falling-down treatment, FIG. 13 is a diagram for explaining step E in the falling-down treatment, and FIG. 14 is a diagram for explaining step F in the falling-down treatment.

[0153] In step SC1, the control unit 101 stops vibration of the ink ejected from the nozzle 12 and application of voltage to the charging electrode 13 and the deflection electrode 15 (ink atomization, charging, deflection: ON→OFF). This stops the ink atomization, charging, and deflection, and an axial ink shaft is ejected from the nozzle 12.

[0154] In step SC2, which follows step SC1, the control unit 101 stops the ejection of the ink shaft (stopping the ejection of ink). Specifically, in this step SC2, in order to stop the ejection of ink, the control unit 101 closes the fourteenth valve V14. This stops the ink from being ejected from the nozzle 12.

[0155] In step SC3 following step SC2, the control unit 101 executes intermittent ejection of the solvent (intermittent ejection of the solvent). Specifically, in order to eject the solvent intermittently, the control unit 101 alternately executes step D illustrated in Fig. 12 and step E illustrated in Fig. 13. By ejecting the solvent intermittently, it is possible to clean the inkjet recording device I, in particular the nozzles 12 constituting the print head 1. Hereinafter, this operation will be referred to as "intermittent ejection operation."

[0156] 12, the control unit 101 opens the sixteenth valve V16, the twelfth valve (also called the solvent injection valve) V12, the tenth valve V10, and the first valve V1. In this state, the solvent pump P2 and the gutter pump P3 are operated, so that the solvent contained in the solvent cartridge 105a is discharged from the nozzle 12 via the first solvent path 31 and collected by the gutter 16. The solvent collected by the gutter 16 is sent back to the main tank 104b via the fifth ink path 25 and the second branch portion 52 (see the thick line in FIG. 12).

[0157] Immediately after starting the process shown in FIG. 11, it is believed that a large amount of ink remains in the fifth ink path 25, so the solvent in step D shown in FIG. 12 is sent back to the main tank 104b rather than to the conditioning tank 105b.

[0158] 13, the control unit 101 closes the twelfth valve V12 and opens the sixth valve V6. Then, due to the negative pressure applied by the circulation pump P4, the solvent remaining in the nozzle 12 is sucked into the main tank 104b via the suction path 27, the first branch part 51, the sixth ink path 26, the first valve V1, and the eighth ink path 28 (see the thick line in FIG. 13).

[0159] 13, the twelfth valve V12 may be left open instead of being closed. In that case, while the solvent is being supplied from the solvent cartridge 105a to the nozzle 12, the supplied solvent is directly sucked through the suction path 27. This improves the flow rate of the solvent flowing through the sixth valve V6, enabling more thorough cleaning.

[0160] Step D shown in Fig. 12 and step E shown in Fig. 13 are repeated multiple times (for example, several sets). Here, the time for performing step D in step SC3 (for example, less than one second) is shorter than the time for performing step E (for example, about several seconds).

[0161] Moreover, the solvent is intermittently sprayed by closing the twelfth valve V12 in step E and then opening the twelfth valve V12 in step D. The twelfth valve V12 may be closed for several seconds when transitioning from step D to step E. This makes it possible to increase the pressure of the solvent in the vicinity of the twelfth valve V12, and to forcefully eject the solvent when the twelfth valve V12 is opened.

[0162] In step SC4, which follows step SC3, the control unit 101 executes only step D shown in Fig. 12 and ejects the solvent from the nozzle 12. The time for executing step D in step SC4 is, for example, about 30 seconds, which is longer than the time for executing step D in step SC3. By executing step SC4, it is possible to mainly clean the fifth ink path 25 leading to the gutter 16. Hereinafter, this operation will be referred to as the "gutter cleaning operation."

[0163] In step SC5, which follows step SC4, the control unit 101 executes step F shown in Fig. 14 to recover the solvent from the print head 1. Specifically, in this step F, the control unit 101 opens the tenth valve V10 and the third valve V3. In this state, the gutter pump P3 operates to suck the solvent remaining in the nozzles 12 into the conditioning tank 105b via the fifth ink path 25 and the second branch portion 52 (see the thick line in Fig. 14). By executing this step S65, the solvent used for cleaning can be recovered.

[0164] Because the solvent was discharged in step SC4 before step SC5 was performed, it is considered that a relatively large amount of solvent remains in the fifth ink path 25. For that reason, the solvent in process F is sent back to the conditioning tank 105b, not to the main tank 104b.

[0165] When the process shown in step SC5 is completed, a return is made, and the control process returns from that shown in Fig. 11 to that shown in Fig. 6. Then, in step SA5 following step SA4, the power supply to the inkjet recording apparatus I is cut off, and the inkjet recording apparatus I stops its operation.

[0166] <Cleaning placement unit 200> As shown in Fig. 1, the cleaning mount 200 is disposed in a location different from the location where the print head 1 is placed when printing is performed by the inkjet recording apparatus I. As shown in Fig. 15, the cleaning mount 200 is configured so that the print head 1 is placed thereon when the print head 1 is cleaned using a cleaning liquid. The cleaning liquid may be a liquid other than a solvent.

[0167] The cleaning mount unit 200 and the print head 1 are connected to be able to communicate with each other, and the connection may be wired or wireless. The print head 1 and the controller 100 are connected to be able to communicate with each other, and the connection may be wired or wireless. The controller 100 and the cleaning mount unit 200 are connected to be able to communicate with each other, and the connection may be wired or wireless. As an example of these connection forms, a signal line capable of transmitting and receiving signals can be used.

[0168] When the installation location of the print head 1 when printing with the inkjet recording apparatus I is specified as shown in Fig. 1, the cleaning mount unit 200 is installed at a location away from that installation location. The cleaning mount unit 200 can be installed away from the controller 100, but it may also be installed at the same location as the controller 100. The cleaning mount unit 200 is a unit that cleans the print head 1 with the print head 1 mounted thereon, and can also be called, for example, a cleaning station, a cleaning dock, a cleaning mount device, a cleaning unit, etc.

[0169] As shown in FIG. 16, the cleaning placement section 200 includes a main body section 210 and a collection container 300 for collecting cleaning liquid from the print head 1. The main body section 210 includes a back plate section 211 extending in the vertical direction. A guide support member 230 for guiding and supporting the print head 1 is provided on the upper portion of the back plate section 211. As shown in FIG. 17, the guide support member 230 includes a pair of left and right rail sections 230a, 230a, and a support section 230b. The rail sections 230a, 230a are provided at intervals from each other in the horizontal direction, both extend in the vertical direction, and are arranged so as to protrude forward from the front surface of the back plate section 211. The upper ends of the rail sections 230a, 230a are open. The support section 230b is a section that supports the print head 1 placed in the correct position, and is composed of a protruding section that protrudes forward from between the rail sections 230a, 230a. The support portion 230b can also be called a stopper portion.

[0170] On the other hand, as shown in Fig. 18, a guided member 18 is provided at the vertical intermediate portion on the rear surface of the housing 10 of the print head 1. The guided member 18 is made of a plate material or the like arranged so as to protrude from the rear surface of the housing 10. On the left side of the guided member 18, a guided portion 18a formed to fit into the left rail portion 230a of the cleaning mount portion 200 is formed so as to protrude leftward. On the right side of the guided member 18, a guided portion 18a formed to fit into the right rail portion 230a of the cleaning mount portion 200 is formed so as to protrude rightward.

[0171] The left and right guided portions 18a, 18a extend in the vertical direction and are formed so that they can be inserted into the rail portions 230a, 230a from the upper ends of the rail portions 230a, 230a of the cleaning platform 200. When inserted into the rail portions 230a, 230a, the guided portions 18a, 18a are guided in the vertical direction by the rail portions 230a, 230a. At this time, the movement direction of the print head 1 is restricted only to the vertical direction and is not allowed to move in the left-right or front-back directions relative to the cleaning platform 200.

[0172] The lower end surface of the guided member 18 is a contact surface 18b that contacts the upper surface of the support portion 230b provided on the guide support member 230 of the cleaning mount 200. The print head 1 can be moved downward with respect to the cleaning mount 200 until the contact surface 18b contacts the upper surface of the support portion 230b shown in FIG. 17. In other words, the height of the print head 1 placed on the cleaning mount 200 can be set by the height of the contact surface 18b of the guided member 18 or the height of the upper surface of the support portion 230b. In this embodiment, the height of the print head 1 placed on the cleaning mount 200 is set as shown in FIG. 15, and this position is the correct position. Although not shown, a rail portion may be provided on the print head 1, and the guided member may be provided on the cleaning mount 200. The structure for positioning the print head 1 at the correct position is not limited to the above-mentioned structure, and any structure may be used as long as the print head 1 can be supported at the correct position by a part of the main body 210.

[0173] As shown in FIG. 16 and FIG. 19, a magnet 211a is provided inside the back plate 211 of the cleaning placement unit 200. The magnet 211a is arranged so that the magnetic force passes through the back plate 211 and acts forward. As shown in FIG. 19, a substrate 211b is provided inside the back plate 211, and a light-emitting element 211c that emits infrared light for infrared communication is mounted on the substrate 211b. As shown in FIG. 20, the light-emitting element 211c is connected to the control unit 101 of the controller 100 and is controlled by the control unit 101. As shown in FIG. 19, the light-emitting surface of the light-emitting element 211c faces forward. The back plate 211 is provided with a transparent member 211d that transmits the infrared light of the light-emitting element 211c. The infrared light irradiated from the light-emitting element 211c passes through the transparent member 211d and is irradiated toward the front of the back plate 211.

[0174] Meanwhile, a substrate 10a is provided inside the housing 10 of the print head 1. A magnetic sensor 10b and a light receiving element 10c for infrared communication are mounted on the substrate 10a. The magnetic sensor 10b is a non-contact magnetic sensor configured to convert a magnetic force equal to or greater than a predetermined threshold value into an electric signal and output the signal, and can be configured, for example, as a Hall element. The magnetic sensor 10b is positioned so as to be at approximately the same height as the magnet 211a of the cleaning placement unit 200 when the print head 10 is in the normal position. The magnetic force is strongest at the same height as the magnet 211a in front of the magnet 211a, and the magnetic sensor 10b is configured to output a magnetic force detection signal only when the print head 10 is in this position. Therefore, for example, if the print sensor 1 is placed above the normal position, the distance between the magnetic sensor 10b and the magnet 211a becomes greater, and the magnetic sensor 10b does not output a magnetic force detection signal. This can be used to detect whether the print head 1 is placed on the cleaning platform 200 and whether it is placed in the correct position. The magnetic sensor 10b is connected to the control unit 101 of the controller 100, and is configured to output a signal to the control unit 101. The control unit 101 may determine whether the print head 1 is placed on the cleaning platform 200 and whether it is placed in the correct position.

[0175] The light receiving element 10c has a light receiving surface facing rearward so as to be able to receive infrared light emitted from the light emitting element 211c of the cleaning placement section 200. The height of the light receiving element 10c is set so that the light receiving element 10c can receive infrared light from the light emitting element 211c only when the print head 10 is in the correct position. The directivity of the infrared light from the light emitting element 211c is narrowed so as not to be diffused over a wide area, and the directivity of the light receiving element 10c is also narrowed so that the light receiving element 10c can receive infrared light from the light emitting element 211c only when the print head 10 is in the correct position. Based on whether or not this communication is established, it is possible to detect whether or not the print head 1 is placed on the cleaning placement section 200 and whether or not it is placed in the correct position. The light receiving element 10c is connected to the control section 101 of the controller 100 and is configured to output a signal to the control section 101. The determination as to whether the print head 1 is placed on the cleaning placement section 200 and whether it is placed in the correct position may be made by the control section 101 based on whether communication is established. The housing 10 is provided with a window section 10d that transmits infrared light from the light emitting element 211c.

[0176] The positions of the light-emitting element 211c and the light-receiving element 10c are not limited to those shown in the figure, but may be in any positional relationship in which the light-receiving element 10c can receive the infrared light irradiated from the light-emitting element 211c only when the print head 1 is placed in the correct position. Similarly, the positions of the magnet 211a and the magnetic sensor 10b are not limited to those shown in the figure, but may be in any positional relationship in which the magnetic sensor 10b outputs a magnetic force detection signal only when the print head 1 is placed in the correct position.

[0177] As described above, magnetic sensor 10b does not output a magnetic force detection signal unless print head 1 is placed on cleaning placement section 200, and therefore magnetic sensor 10b corresponds to a placement detection section that detects that print head 1 has been placed on cleaning placement section 200. Furthermore, magnetic sensor 10b does not output a magnetic force detection signal unless print head 1 is placed in the correct position relative to cleaning placement section 200, and therefore magnetic sensor 10b can also detect that print head 1 has been placed in the correct position relative to cleaning placement section 200. The magnetic force detection signal is a signal based on confirmation that print head 1 has been placed.

[0178] Furthermore, since the light receiving element 10c cannot receive the infrared light irradiated from the light emitting element 211c unless the print head 1 is placed on the cleaning placement section 200, the light receiving element 10c corresponds to a placement detection section that detects that the print head 1 is placed on the cleaning placement section 200. Furthermore, since the light receiving element 10c cannot receive the infrared light irradiated from the light emitting element 211c unless the print head 1 is placed in the correct position with respect to the cleaning placement section 200, the light receiving element 10c can also detect that the print head 1 is placed in the correct position with respect to the cleaning placement section 200. Furthermore, since it can be presumed that the print head 1 is not placed if the light emitting element 211c and the light receiving element 10c cannot perform infrared communication, the control section 101 can detect that the print head 1 is placed on the cleaning placement section 200 when infrared communication is possible, based on the output of the light receiving element 10c. Similarly, if the print head 1 is not placed in the correct position with respect to the cleaning platform 200, infrared communication cannot be performed between the light emitting element 211c and the light receiving element 10c, and therefore the control unit 101 can detect that the print head 1 is placed in the correct position with respect to the cleaning platform 200 when infrared communication is possible based on the output of the light receiving element 10c. The infrared communication signal acquired by the light receiving element 10c is a signal based on confirmation that the print head 1 is placed.

[0179] The magnetic force detection signal output from the magnetic sensor 10b and the infrared communication signal acquired by the light receiving element 10c are sent from the print head 1 to the control unit 101 of the controller 100 via a connection cable 107.

[0180] The placement detection unit may be, other than those using magnetic detection signals or infrared communication, a proximity sensor, a photoelectric sensor, a laser sensor, etc. When using these sensors, when the distance between the print head 1 and the cleaning placement unit 200 becomes equal to or less than a predetermined distance, it can detect that the print head 1 has been placed on the cleaning placement unit 200 or that it has been placed in the correct position.

[0181] In this embodiment, both a magnetic force detection signal and infrared communication are configured to be output as signals based on confirmation of placement of the print head 1, but it may be configured to output only one of these. By outputting two or more types of signals based on confirmation of placement of the print head 1, it is possible to improve detection accuracy.

[0182] As shown in FIG. 16, the back plate 211 is provided with a bottom wall 212 extending forward from a vertical middle portion, and a peripheral wall 213 extending upward from the bottom wall 212, forming a cup shape with the bottom wall 212 and the peripheral wall 213. As shown by imaginary lines in FIG. 24, the lower side of the print head 1 placed in the correct position is inserted into the peripheral wall 213. In this state, the upper side of the print head 1 protrudes upward from the upper end of the peripheral wall 213. The bottom wall 212 is located below and away from the discharge port A (shown in FIG. 5) of the print head 1. The solvent used when cleaning the print head 1 mainly leaks out from the discharge port A of the print head 1, but the solvent leaking out from the discharge port A can be received by the bottom wall 212 and the peripheral wall 213. For the purposes of explanation, the bottom wall portion 212 and the peripheral wall portion 213 are shown as separate, but they may also be integrated with an indistinguishable boundary; in short, they need only be formed into a bottomed cylindrical shape capable of accommodating the underside of the print head 1.

[0183] <Attachment structure of collection container 300> As shown in FIG. 16, a collection container 300 for collecting the cleaning agent of the print head 1 is attached to the bottom wall 212. The collection container 300 can be made of, for example, a resin bottle, and can be one that is translucent so that the amount of cleaning liquid inside can be known from the outside, or one that has a scale. As shown in a modified example in FIG. 21, instead of directly attaching the collection container 300 to the bottom wall 212, a tube 350 made of, for example, a hose or a piping member can be attached to the bottom wall 212, and the cleaning liquid can be collected in another collection container (not shown) through the tube 350. In this case, the collection container can be provided in the controller 100. The tube 350 may be a member that constitutes a part of the collection container, or may be a member that constitutes a part of the cleaning placement unit 200. The attachment structure of the collection container 300 to the bottom wall 212 and the attachment structure of the tube 350 to the bottom wall 212 may be different or the same. The attachment structure of the collection container 300 to the bottom wall 212 will be described in detail below.

[0184] 22, a cylindrical mouth portion 301 is provided at the upper portion of the collection container 300. A screw thread 301a is formed on the outer circumferential surface of the mouth portion 301. A flange portion 301b is formed below the screw thread 301a on the outer circumferential surface of the mouth portion 301. The collection container 300 can be a member that constitutes a part of the cleaning mount portion 200.

[0185] 24, a cylindrical portion 212a protruding downward is formed on the bottom wall portion 212. The outer diameter of the cylindrical portion 212a is set to be smaller than the inner diameter of the mouth portion 301 of the collection container 300. The lower end portion of the cylindrical portion 212a is inserted into the inside of the collection container 300 in a state in which the collection container 300 is attached to the bottom wall portion 212 as shown in FIG. 26, and reaches below the lower end portion of the mouth portion 301.

[0186] 24, a through hole 212b through which the cleaning liquid for the print head 1 passes is formed to extend in the vertical direction within the cylindrical portion 212a. The upper end of the through hole 212b opens at a portion near the front of the upper surface of the bottom wall portion 212. The lower end of the through hole 212b opens at the lower end of the cylindrical portion 212a.

[0187] 25, a receiving member 214 made of a conductive metal plate is provided on the upper surface of the bottom wall portion 212. The receiving member 214 is a member that receives ink leaking from the print head 1 and is connected to an equipotential line. The ink leaking from the print head 1 may be charged by the charging electrode 13 or the deflection electrode 15. When the charged ink comes into contact with the receiving member 214, the charge of the ink can be released, thereby making it possible to suppress the accumulation of charge.

[0188] The receiving member 214 is disposed so as to face the ejection hole A of the print head 1. As shown in Fig. 24, the receiving member 214 is inclined so that it is positioned lower as it approaches the front side. This allows the cleaning liquid received by the receiving member 214 to be guided by the receiving member 214 toward the front side of the bottom wall portion 212 and flow toward the upper end opening of the passing hole 212b.

[0189] A protruding plate portion 214a protruding upward is formed at the front end portion and the middle portion in the front-rear direction of the receiving member 214. An opening portion 214b is also formed in the receiving member 214. The protruding plate portion 214a and the opening portion 214b are not essential.

[0190] The mounting tube portion 215 is formed on the lower surface of the bottom wall portion 212 so as to protrude downward. The mounting tube portion 215 has a larger diameter than the cylindrical portion 212a so as to surround the cylindrical portion 212a. The lower end of the mounting tube portion 215 is located above the lower end of the cylindrical portion 212a. A screw groove 215a is formed on the inner peripheral surface of the mounting tube portion 215. The screw thread 301a of the collection container 300 is screwed into the screw groove 215a. By screwing the screw thread 301a of the collection container 300 into the screw groove 215a, the collection container 300 can be attached to the bottom wall portion 212 without liquid leakage. As shown in FIG. 26, in the attached state of the collection container 300, the mouth portion 301 enters the mounting tube portion 215, and the lower end of the cylindrical portion 212a is disposed in the collection container 300. The pipe 350 shown in FIG. 21 can also be attached by a screw.

[0191] 16 and 22, the cleaning placement section 200 includes a container holder 220. The container holder 220 is attached to a portion of the back plate section 211 of the main body section 210 that is lower than the bottom wall section 212 so as to be slidable in the up and down direction. The container holder 220 has a pair of left and right engagement protrusions 221, 221 that are provided so as to protrude forward. A gap is formed between the engagement protrusions 221, 221 into which the mouth section 301 of the collection container 300 can be inserted laterally. The left-right separation distance between the engaging protrusions 221, 221 is set shorter than the outer diameter dimension of the flange portion 301b of the mouth portion 301, so that by inserting the mouth portion 301 of the collection container 300 between the engaging protrusions 221, 221 laterally (in the direction indicated by arrow X in Figure 22), the flange portion 301b of the mouth portion 301 can be hooked and held from above against the engaging protrusions 221, 221.

[0192] Container holder 220 can be switched between a non-attached position shown in Figures 22 to 24 and a completed attachment position shown in Figures 15, 16, 26, etc. Container holder 220 can be stopped from moving downward from the non-attached position by a well-known locking mechanism, stopper, etc., and the user can easily switch it from the non-attached position to the completed attachment position. Cleaning placement unit 200 may be provided with a biasing member such as a spring that biases container holder 220 downward.

[0193] The non-attached position is the lower end position of the container holder 220, and is the position where the collection container 300 is removed from the cleaning placement unit 200. In the non-attached position, the mouth 301 of the collection container 300 can be inserted between the engagement protrusions 221, 221, and the mouth 301 inserted between the engagement protrusions 221, 221 can be removed. The container holder 220 in the non-attached position can be switched to the attachment completion position by moving it upward, i.e., vertically. In this attachment completion position, the container holder 220 is in the upper end position, and the mouth 301 of the collection container 300 cannot be inserted between the engagement protrusions 221, 221. Since the mouth 301 of the collection container 300 held by the container holder 220 in the attachment completion position is inserted into the mounting tube portion 215, the collection container 300 cannot be moved horizontally.

[0194] After container holder 220 is placed in the mounting position while holding container holder 220, collection container 300 is rotated in a direction in which thread 301a of opening 301 is screwed into thread groove 215a of mounting tube 215, so that collection container 300 can be attached to bottom wall 212 by screwing thread 301a into thread groove 215a. In the process of screwing thread 301a into thread groove 215a, collection container 300 gradually moves upward. As collection container 300 moves upward, container holder 220 is pushed upward by collection container 300, and reaches the mounting completion position shown in FIG. 26. In this state, the lower end opening of passage hole 212b formed in bottom wall 212 is positioned to face inside collection container 300, so that the entire amount of cleaning liquid leaking from print head 1 can be collected by collection container 300.

[0195] When removing the collection container 300, the collection container 300 is rotated in the opposite direction to that at the time of attachment to separate the mouth portion 301 from the attachment tube portion 215. Thereafter, the container holder 220 is switched to the non-attached position, and the collection container 300 is moved laterally to remove the mouth portion 301 from between the engagement protrusions 221, 221.

[0196] The mounting structure of collection container 300 is not limited to the above-mentioned structure, and may be, for example, a structure in which mouth portion 301 of collection container 300 is press-fitted into mounting tube portion 215. Pipe 350 shown in Fig. 21 may also be a structure in which it is press-fitted into mounting tube portion 215. Furthermore, container holder 220 may be configured to be attached to collection container 300 and guided by main body portion 210. Furthermore, container holder 220 may be omitted.

[0197] <Container detection sensor 235> As shown in FIG. 24, the cleaning placement unit 200 includes a container detection sensor 235 as a container detection unit that detects that the collection container 300 is attached. A non-contact magnetic sensor can be used as the container detection sensor 235, and it can be configured with, for example, a Hall element. That is, the container holder 220 is provided with a magnet 231. The magnet 231 is disposed so that a magnetic force acts upward. On the other hand, the container detection sensor 235 is provided, for example, inside the bottom wall portion 212, and disposed directly above the magnet 231. When the container holder 220 is in the non-attached position, the magnet 231 and the container detection sensor 235 are the farthest apart, and the container detection sensor 235 cannot detect the magnetic force of the magnet 231, and therefore the container detection sensor 235 does not output a magnetic force detection signal. As shown in Fig. 26, when the screw thread 301a of the mouth portion 301 is screwed into the screw groove 215a of the mounting tube portion 215 and the container holder 220 is in the mounting completion position, the container holder 220 is in the mounting completion position, so that the magnet 231 and the container detection sensor 235 are closest to each other. Only at this time, the container detection sensor 235 is configured to output a magnetic force detection signal. In other words, even if the collection container 300 is held by the container holder 220, if the mouth portion 301 is not connected to the mounting tube portion 215, the container detection sensor 235 is configured not to output a magnetic force detection signal. The container detection sensor 235 is connected to the control unit 101 of the controller 100 and configured to output a signal to the control unit 101.

[0198] Although not shown, the magnet may be provided on the collection container 300. In this case as well, the container detection sensor 235 turns ON only when the collection container 300 reaches the installation completion position, so that the container detection sensor 235 can detect that the collection container 300 has been attached. When the container holder 220 is omitted, a magnet can be provided on the collection container 300 to detect that the collection container 300 has been attached.

[0199] The container detection unit may be, for example, a proximity sensor, a photoelectric sensor, a laser sensor, or the above-mentioned infrared communication, other than the one using the magnetic detection signal. When a proximity sensor, a photoelectric sensor, or a laser sensor is used, when the distance between the collection container 300 and the bottom wall 212 becomes equal to or less than a predetermined distance, it can detect that the collection container 300 has been attached to the bottom wall 212. In the case of infrared communication, a light-emitting element is provided on one of the collection container 300 and the bottom wall 212, and a light-receiving element is provided on the other, and it can be determined that the collection container 300 has been attached to the bottom wall 212 based on whether communication between the light-emitting element and the light-receiving element is possible.

[0200] When a biasing member that biases the container holder 200 downward is provided, it is possible to prevent the container holder 200 from being placed at the upper end position alone without the collection container 300 attached, thereby preventing erroneous detection by the container detection sensor 235.

[0201] <Liquid volume sensor 240> As shown in FIG. 23 and FIG. 27, the cleaning placement unit 200 includes a liquid level sensor 240 that detects the amount of liquid in the collection container 300. The liquid level sensor 240 includes two electrodes. These electrodes protrude downward from the lower surface of the bottom wall portion 212, and are formed so as to reach below the mouth portion 301 of the collection container 300 in the attached state. The measurement principle of the liquid level sensor 240 utilizes the fact that the cleaning liquid containing ink is a conductor, and can measure the impedance between the two electrodes and detect whether the liquid amount is equal to or greater than a predetermined amount based on the change in impedance. For example, the positions of the lower ends of both electrodes can be set so that they come into contact with the cleaning liquid when the liquid level of the cleaning liquid reaches the vicinity of the mouth portion 301 in the collection container 300. In this case, if the impedance between the two electrodes suddenly changes, it means that the cleaning liquid is full, and the liquid level sensor 240 can be used as a sensor that detects the full amount. The liquid level sensor 240 can also be called an overflow detection sensor that detects the state immediately before the cleaning liquid overflows. The liquid level sensor 240 is connected to the control unit 101 of the controller 100 and is configured to output a signal to the control unit 101 .

[0202] When the pure cleaning liquid is non-conductive, ink can be always contained in the cleaning liquid in the collection container 300 by controlling the ejection of a small amount of ink from the nozzle 12 before the cleaning operation. This makes it possible to utilize the above-mentioned detection method.

[0203] The configuration of the liquid level sensor 240 is not limited to the above-mentioned configuration, and any sensor may be used as long as it can directly or indirectly obtain the level of the cleaning liquid in the collection container 300 and the amount and weight of the cleaning liquid in the collection container 300. An example of a sensor that obtains the level of the cleaning liquid is a displacement sensor. When the displacement sensor detects the liquid level, the presence or absence of the collection container 300 can also be detected by the displacement sensor.

[0204] Furthermore, the liquid level sensor 240 may be, for example, a float sensor, a capacitance type level sensor, a photoelectric sensor, or the like.

[0205] <Maintenance execution process> FIG. 28 is a flow chart illustrating the process performed when performing maintenance. Maintenance is, for example, a cleaning operation. The following judgments and controls can be performed by the control unit 101 of the controller 100. When the user sets the print head 1 on the cleaning platform 200, in step SE1 it is judged whether the print head 1 has been placed in the correct position with respect to the cleaning platform 200. For this judgment, the output signal of the magnetic sensor 10b can be used. If a magnetic force detection signal is output from the magnetic sensor 10b, the print head 1 is placed in the correct position on the cleaning platform 200, so a YES judgment is made, whereas if a magnetic force detection signal is not output from the magnetic sensor 10b, the print head 1 is not placed in the correct position on the cleaning platform 200, so a NO judgment is made. In step SE1, the determination can also be made based on whether infrared communication between the light-emitting element 211c and the light-receiving element 10c has been established. In this case, if infrared communication between the light-emitting element 211c and the light-receiving element 10c is established, the determination is YES, whereas if infrared communication between the light-emitting element 211c and the light-receiving element 10c is not established, the determination is NO. In addition, in step SE1, the determination can also be made based on both the signal of the magnetic sensor 10b and the infrared communication. If the magnetic force detection signal is not output from the magnetic sensor 10b or infrared communication is not established, the determination is NO. If the determination is YES in step SE1, the process proceeds to step SE4.

[0206] On the other hand, if the determination in step SE1 is NO and the process proceeds to step SE2, a message is issued to place the print head 1 in the correct position. The message can be displayed, for example, on display unit 103a shown in FIG. 2. This makes it possible to prompt the user to check the position of the print head 1. The process then proceeds to step SE3, where a determination similar to that in step SE1 is made, and if the determination is NO, the process proceeds to step SE2 and the message is issued again. If the determination in step SE3 is YES and the print head 1 is placed in the correct position, the process proceeds to step SE4.

[0207] In step SE4, it is determined whether the container detection sensor 235 is ON, that is, whether the collection container 300 is attached. When the collection container 300 is attached, the container detection sensor 235 outputs a magnetic force detection signal (the container detection sensor 235 turns ON), so in this case, it is determined as YES and the process proceeds to step SE7. On the other hand, when the collection container 300 is not attached, it is determined as NO in step SE4 and the process proceeds to step SE5, where a message is issued to attach the collection container 300. The message can be displayed, for example, on the display unit 103a shown in FIG. 2. This makes it possible to prompt the user to attach the collection container 300. Thereafter, it proceeds to step SE6, where a determination similar to that in step SE4 is made, and if it is determined as NO, it proceeds to step SE5 and the message is issued again. When it is determined as YES in step SE6 and the collection container 300 is attached, it proceeds to step SE7.

[0208] In step SE7, it is determined whether the liquid level sensor is ON, that is, whether the collection container 300 is full or nearly full. If the collection container 300 is not full or nearly full, the liquid level sensor 240 is OFF, so in this case, it is determined as YES and the process proceeds to step SE10. On the other hand, if the collection container 300 is full or nearly full, it is determined as NO in step SE7 and the process proceeds to step SE8, where a message is issued to discard the cleaning liquid in the collection container 300. The message can be displayed, for example, on the display unit 103a shown in FIG. 2. This makes it possible to prompt the user to discard the liquid in the collection container 300. Thereafter, it proceeds to step SE9, where a determination similar to that in step SE7 is made, and if it is determined as NO, it proceeds to step SE8 and a message is issued again. If it is determined as YES in step SE9 and the liquid is discarded, it proceeds to step SE10. In step SE10, a cleaning operation permission signal is output to enable various maintenance operations to be performed.

[0209] In this example, if the cleaning operation unit 101a of the controller 100 receives a signal (magnetic force detection signal) based on confirmation of placement of the print head 1 sent from the magnetic sensor 10b, which is the placement detection unit, in step SE1 or SE3, it performs a cleaning operation of the print head 1 placed on the cleaning placement unit 200, and prohibits the cleaning operation in other cases. Also, if the cleaning operation unit 101a of the controller 100 receives an infrared communication signal (signal based on confirmation of placement of the print head 1) acquired by the light receiving element 10c in step SE1 or SE3, it performs a cleaning operation of the print head 1 placed on the cleaning placement unit 200, and prohibits the cleaning operation in other cases. In other words, in step SE1 or SE3, when the cleaning operation unit 101a does not receive a signal based on confirmation of placement of the print head 1, it can prohibit the cleaning operation of the print head 1.

[0210] <Connection confirmation process> In the processing of the flowchart shown in Figure 28 described above, when a signal based on confirmation of the placement of the print head 1 is received, the collection container 300 and the liquid volume are detected, and if there are no problems, the cleaning operation unit 101a performs the operation of cleaning the print head 1. If only one automatic printing system S has been installed at a site, the print head 1 placed on the cleaning placement stage 200 belongs to that automatic printing system S, so no particular problems will arise in the processing of the flowchart shown in Figure 28.

[0211] However, as shown in Fig. 29, there are cases where multiple automatic printing systems S are installed at one site. In this example, one automatic printing system S is made up of a first controller A, a first print head A, and a first cleaning platform A, and another automatic printing system S is made up of a second controller B, a second print head B, and a second cleaning platform B. The first and second print heads A and B have the same structure and shape, and the first and second cleaning platform A and B also have the same structure and shape. Therefore, as shown in Fig. 29, if a user intends to place the first print head A connected to the first controller A on the first cleaning platform A to clean it, but mistakenly places the second print head B connected to the second controller B on the first cleaning platform A, the first print head A will not be placed on either of the cleaning platform parts A or B. If automatic cleaning were to be performed in this state, there would be nothing to receive the cleaning liquid leaking from the first print head A, and so the cleaning liquid could contaminate the surrounding environment or evaporate, creating an undesirable environment. In other words, in the process of the flowchart shown in Figure 28, cleaning of the print head 1 may be performed even if it has been placed incorrectly.

[0212] In this case, the process of the flowchart shown in Figure 30 can be performed. In step SF1, placement of the print head 1 on the cleaning placement section 200 is detected. This can be detected based on a magnetic force detection signal output from the magnetic sensor 10b or an infrared communication signal acquired by the light receiving element 10c. Then, in step SF2, the cleaning operation section 101a of the controller 100 confirms that the print head 1 has been placed.

[0213] In step SF3, the serial number, which is identification information possessed by the controller 100, is transmitted to the cleaning placement section 200. The identification information possessed by the controller 100 is not limited to the serial number, but may be information unique to the controller 100, and may be composed of, for example, numbers, letters, symbols, etc., and may be composed of any one of numbers, letters, symbols, etc., or may be composed of any two or more of them in combination. The identification information possessed by the controller 100 may be a random number.

[0214] In step SF4, the cleaning placement unit 200 receives the serial number transmitted from the controller 100. In step SF5, the cleaning placement unit 200 transmits the serial number transmitted from the controller 100 to the print head 1. At this time, the transmission can be performed by infrared communication using the light emitting element 211c and the light receiving element 10c. In step SF6, the print head 1 receives the serial number of the controller 100 transmitted from the cleaning placement unit 200. In step SF7, the serial number of the controller 100 transmitted from the cleaning placement unit 200 is transmitted to the controller 100. In step SF8, the controller 100 receives the serial number transmitted from the print head 1. In step SF9, the control unit 101 of the controller 100 determines whether the serial number of the controller 100 transmitted from the print head 1 matches the serial number transmitted by the controller 100 in step SF3. This process is an authentication process to determine whether the print head 1 placed on the cleaning mount section 200 is the one connected to the controller 100. If the two do not match, it means that the print head 1 is not connected to this controller 100, so the process does not proceed to the following step, but returns to step SF3, and the processes of steps SF3 to SF9 are repeated. If it is determined in step SF9 that there is a mismatch even after a predetermined number of repetitions, this flow is interrupted and a notification is given to the user, or an error message is displayed.

[0215] On the other hand, if it is determined in step SF9 that the serial number of the controller 100 transmitted from the print head 1 matches the serial number transmitted by the controller 100 in step SF3, the process proceeds to step SF10. In step SF10, a request for output of a sensor state is made to the cleaning placement unit 200. In step SF11, the cleaning placement unit 200 transmits the sensor state, i.e., the state of the container detection sensor 235 and the liquid volume sensor 240, to the cleaning operation unit 101a of the controller 100. In step SF12, the cleaning operation unit 101a receives the sensor state. In step SF13, it is confirmed whether maintenance can be performed.

[0216] The flow chart for checking is shown in Fig. 31. After starting to check the sensor state, in step SG1, the state of magnetic sensor 10b is checked. If magnetic sensor 10b is ON, i.e., outputs a magnetic force detection signal, the process proceeds to step SG2, whereas if magnetic sensor 10b is OFF, i.e., does not output a magnetic force detection signal, the process proceeds to step SG4. Instead of magnetic sensor 10b, an infrared communication signal acquired by light receiving element 10c can be used.

[0217] In step SG2, the state of the container detection sensor 235 is confirmed. If the container detection sensor 235 is ON, that is, if the collection container 300 is attached, the process proceeds to step SG3, whereas if the container detection sensor 235 is OFF, that is, if the collection container 300 is not attached, the process proceeds to step SG4. In step SG3, the state of the liquid level sensor 240 is confirmed. If the liquid level sensor 240 is OFF, that is, if the amount of cleaning agent in the collection container 300 is less than full, the process returns to the first step and maintenance can be performed, whereas if the liquid level sensor 240 is ON, that is, if the amount of cleaning agent in the collection container 300 is full, the process proceeds to step SG4. In step SG4, maintenance is prohibited, so the cleaning operation unit 101a does not permit the cleaning operation. Unless the process proceeds to step SG4, the cleaning operation unit 101a permits the cleaning operation. Therefore, in step SF13 of the flowchart shown in FIG. 30, the determination is made as "possible" and the process proceeds to step SF14. When the process proceeds to step SG4 in the flowchart shown in FIG. 31, it is determined that "impossible" in step SF13 in the flowchart shown in FIG. 30, and the process returns to step SF10.

[0218] In step SF14, the cleaning operation unit 101a performs maintenance. Specifically, the solvent pump P2 of the controller 100 is operated and the solvent injection valve is opened. During the cleaning operation, the flowchart shown in Fig. 31 is repeatedly executed, and when the process proceeds to step SG4, the cleaning operation unit 101a stops the cleaning operation.

[0219] The print head 1 is configured to send a signal based on confirmation of placement of the print head 1 in step SF1, and to send the identification information of the controller 100 previously acquired via a signal line to the controller 100 in step SF7. Therefore, the cleaning operation is not performed simply by placing the print head 1, and the cleaning operation is not performed unless the identification information of the controller 100 matches in step SF9. For example, as shown in FIG. 29, when the second print head B is placed on the first cleaning placement part A, the identification information sent from the first controller A is received by the second controller B, and as a result, it is not sent to the first controller A, so that the first controller A does not perform the cleaning operation. This makes it possible to prevent the cleaning liquid from leaking from the first print head A.

[0220] It is also possible to configure so that when sending a signal based on confirmation of the placement of the print head 1 in step SF1, identification information of the print head 1 is also sent to the controller 100. If identification information consisting of a unique identification number or the like is given to the print head 1 connected to the controller 100, it is possible to confirm whether or not it is the print head 1 connected to the controller 100 by checking the identification information of the print head 1 with the controller 100. The cleaning operation unit 101a can be configured so that when confirmation of the placement of the print head 1 has been performed and it has been confirmed that it is the print head 1 connected to the controller 100, the cleaning operation of the print head 1 is permitted.

[0221] <Variation 1> FIG. 32 is a simplified block diagram according to a first modified example of the embodiment. In the first modified example, the print head 1 is provided with a magnet 10e and a light-emitting element 10f, and the light-emitting element 10f is controlled by the control unit 101 of the controller 100. The mounting and cleaning unit 200 is provided with a magnetic sensor 200a and a light-receiving element 200b. The magnetic sensor 200a of the mounting and cleaning unit 200 is capable of detecting the magnetic force of the magnet 10e of the print head 1. The light-receiving element 200b of the mounting and cleaning unit 200 is capable of receiving infrared light emitted by the light-emitting element 10f of the print head 1. The magnetic sensor 200a and the light-receiving element 200b are connected to the control unit 101 of the controller 100. In the first modified example, the mounting of the print head 10 can be confirmed and whether or not it is in the correct position can be accurately determined based on the results of detection by the infrared communication and the magnetic sensor 200a.

[0222] 33 is a flowchart illustrating a process according to the first modification of the embodiment. In step SH1, the cleaning placement unit 200 detects that the print head 1 has been placed on the cleaning placement unit 200. This can be detected based on a magnetic force detection signal output from the magnetic sensor 200a or an infrared communication signal acquired by the light receiving element 200b. Then, in step SH2, the cleaning operation unit 101a of the controller 100 confirms that the print head 1 has been placed.

[0223] In step SH3, the serial number, which is identification information possessed by the controller 100, is transmitted to the print head 1. In step SH4, the print head 1 receives the serial number transmitted from the controller 100. In step SH5, the print head 1 transmits the serial number transmitted from the controller 100 to the cleaning platform 200. At this time, the transmission can be performed by infrared communication using the light emitting element 10f and the light receiving element 200b. In step SH6, the cleaning platform 200 receives the serial number of the controller 100 transmitted from the print head 1. In step SH7, the serial number of the controller 100 transmitted from the print head 1 is transmitted to the controller 100. In step SH8, the controller 100 receives the serial number transmitted from the cleaning platform 200. Steps SH9 to SH16 are the same as steps SF9 to SF16, respectively, in the flowchart shown in FIG. 30. As a result, if the serial numbers do not match in step SH9, the cleaning operation is not carried out, so the first print head A will not be cleaned in the state shown in FIG.

[0224] <Variation 2> FIG. 34 is a simplified block diagram according to a second modification of the embodiment. In the second modification, the print head 1 is provided with not only the light receiving element 10c but also the light emitting element 10f. The light emitting element 10f is controlled by the control unit 101 of the controller 100. The cleaning placement unit 200 is provided with not only the light emitting element 211c but also the light receiving element 200b. Furthermore, the cleaning placement unit 200 is provided with the control unit 200c. The container detection sensor 235, the liquid level sensor 240, the light receiving element 200b, and the light emitting element 211c are connected to the control unit 200c. The detection results of the container detection sensor 235 and the liquid level sensor 240 and the information received by the light receiving element 200b are processed by the control unit 200c, and then transmitted to the print head 1 side by the light emitting element 211c and received by the light receiving element 10c. The information received by the print head 1 is transmitted to the control unit 101 of the controller 100. In this second modification, the controller 100 only supplies power to the washing platform 200, and there is no direct communication between the controller 100 and the washing platform 200. The washing platform 200 may include a built-in battery.

[0225] 35 is a flow chart illustrating a process according to the second modification of the embodiment. In step SI1, the print head 1 detects that it has been placed on the cleaning placement unit 200. This can be detected based on a magnetic force detection signal output from the magnetic sensor 10b or an infrared communication signal acquired by the light receiving element 10c. Then, in step SI2, the cleaning operation unit 101a of the controller 100 confirms that the print head 1 has been placed.

[0226] In step SI3, a sensor status output request is made to the print head 1. In step SI4, the print head 1 makes a sensor status output request to the cleaning platform 200. In step SI5, the cleaning platform 200 receives the sensor status output request sent from the print head 1. In step SI6, the cleaning platform 200 sends the status of the container detection sensor 235 and the liquid volume sensor 240 to the print head 1. In step SI7, the print head 1 receives the status of the container detection sensor 235 and the liquid volume sensor 240 sent from the cleaning platform 200.

[0227] In step SI8, the status of the container detection sensor 235 and the liquid level sensor 240 is received to check whether maintenance can be performed. If "possible", the process proceeds to step SI9, and then to steps SI10 and SI11, where the cleaning operation is performed. If "not possible", the process returns to step SI13.

[0228] In this variant example 2, the states of the container detection sensor 235 and the liquid level sensor 240 can be obtained via the print head 1, so that even in the case of incorrect placement as shown in Figure 29, control can be performed based on the states of the container detection sensor 235 and the liquid level sensor 240, ensuring safety.

[0229] <Modification 3> 36 is a simplified block diagram according to a third modification of the embodiment. In the third modification, the cleaning placement unit 200 is provided with a control unit 200c. The control unit 200c is connected to a magnetic sensor 211a, a container detection sensor 235, a liquid level sensor 240, and a light-emitting element 211c. The detection results of the magnetic sensor 211a, the container detection sensor 235, and the liquid level sensor 240 are processed by the control unit 200c, and then transmitted to the print head 1 side by the light-emitting element 211c, and received by the light-receiving element 10c. The information received by the print head 1 is transmitted to the control unit 101 of the controller 100. In the third modification, the controller 100 only supplies power to the cleaning placement unit 200, and no direct communication is performed between the controller 100 and the cleaning placement unit 200.

[0230] 37 is a flow chart illustrating a process according to the third modification of the embodiment. In step SJ1, the cleaning platform 200 detects that the print head 1 has been placed on the cleaning platform 200. This can be detected based on a magnetic force detection signal output from the magnetic sensor 211a. Then, in step SJ2, the cleaning platform 200 transmits the states of the container detection sensor 235 and the liquid volume sensor 240 to the print head 1. In step SJ3, the print head 1 transmits the sensor states transmitted from the cleaning platform 200 to the controller 100.

[0231] In step SJ4, the status of the container detection sensor 235 and the liquid level sensor 240 is received to check whether maintenance can be performed. If "possible," the process proceeds to step SJ5, and then to steps SJ6 and SJ7, where the cleaning operation is performed. If "not possible," the flow ends.

[0232] In the third modification, when the cleaning placement unit 200 detects placement, it outputs the sensor state in a one-way manner, instead of using a command response method from the controller 100. This allows the infrared communication unit to be configured for one-way communication, thereby reducing the number of light emitting elements and light receiving elements.

[0233] <Modification 4> FIG. 38 is a simplified block diagram according to the fourth modification of the embodiment. In the fourth modification, the cleaning placement unit 200 is provided with a cleaning agent nozzle 200d and a cleaning agent pump P5, and also with a control unit 200c. A cleaning agent tank or a cleaning agent cartridge (not shown) is connected to the cleaning agent pump P5. The control unit 200c is connected with a magnetic sensor 211a, a container detection sensor 235, a liquid level sensor 240, and a light emitting element 211c. The detection results of the magnetic sensor 211a, the container detection sensor 235, and the liquid level sensor 240 are processed by the control unit 200c, and the control unit 200c controls the solenoid valve (cleaning agent injection valve) of the cleaning agent nozzle 200d and the cleaning agent pump P5 to perform a cleaning operation. The cleaning agent nozzle 200d can be arranged as the cleaning agent nozzle 360 ​​shown in FIG. 24. In this fourth modification, since it is not necessary to use the solvent in the controller 100 as a cleaning agent, water or a water-soluble cleaning agent can be used.

[0234] 39 is a flowchart illustrating a process according to the third modification of the embodiment. In step SK1, the cleaning placement unit 200 detects that the print head 1 has been placed on the cleaning placement unit 200. This can be detected based on a magnetic force detection signal output from the magnetic sensor 211a. Then, in step SK2, the cleaning operation unit 101a of the controller 100 confirms that the print head 1 has been placed.

[0235] In step SK3, the serial number, which is the identification information possessed by the controller 100, is transmitted to the cleaning placement unit 200. In step SK4, the cleaning placement unit 200 receives the serial number transmitted from the controller 100. In step SK5, the cleaning placement unit 200 transmits the serial number transmitted from the controller 100 to the print head 1. In step SK6, the print head 1 receives the serial number of the controller 100 transmitted from the cleaning placement unit 200. In step SK7, the serial number of the controller 100 transmitted from the cleaning placement unit 200 is transmitted to the controller 100. In step SK8, the controller 100 receives the serial number transmitted from the print head 1. In step SK9, it is determined whether the serial number of the controller 100 transmitted from the print head 1 matches the serial number transmitted by the controller 100 in step SK3. If they do not match, the process returns to step SK3.

[0236] On the other hand, if it is determined in step SK9 that the serial number of the controller 100 transmitted from the print head 1 matches the serial number transmitted by the controller 100 in step SK3, the process proceeds to step SK10. In step SK10, a maintenance execution request is transmitted to the cleaning placement unit 200. In step SK11, the states of the container detection sensor 235 and the liquid level sensor 240 are transmitted to the control unit 200c. In step SK12, the control unit 200c determines whether or not maintenance can be performed based on the states of the container detection sensor 235 and the liquid level sensor 240. If it is "impossible," the process returns to step SK10. If it is "possible," the process proceeds to step SK13, and then the pump P5 is operated in step SK14, and the cleaning agent injection valve is opened in step SK15.

[0237] <Variation 5> 40 is a simplified block diagram according to a fifth modification of the embodiment. In the fifth modification, the print head 1 has an AND circuit, which can control the solenoid valve of the cleaning nozzle 19. A control signal from the control unit 101 and an output signal from the magnetic sensor 10b are input to the AND circuit. When the control signal from the control unit 101 is a cleaning operation permission signal and a magnetic force detection signal from the magnetic sensor 10b is input, the solenoid valve of the cleaning nozzle 19 can be switched from closed to open to perform the cleaning operation.

[0238] 41 is a flow chart illustrating a process according to the third modified example of the embodiment. In step SL1, the controller 100 transmits a serial number to the cleaning platform 200. In step SL2, the cleaning platform 200 receives the serial number transmitted from the controller 100. In step SL3, the cleaning platform 200 transmits the serial number received from the controller 100 to the print head 1. In step SL4, the print head 1 receives the serial number transmitted from the cleaning platform 200. In step SL5, the print head 1 transmits the serial number received from the cleaning platform 200 to the controller 100. In step SL6, the controller 100 receives the serial number transmitted from the print head 1.

[0239] In step SL7, it is determined whether the serial number of the controller 100 transmitted from the print head 1 matches the serial number transmitted by the controller 100 in step SL1. If they do not match, the process returns to step SL1. If they match, the process proceeds to step SL8, where a request to output the sensor status is made to the cleaning placement unit 200. In step SL9, the cleaning placement unit 200 transmits the status of the container detection sensor 235 and the liquid volume sensor 240 to the controller 100. In step SL10, the status of the container detection sensor 235 and the liquid volume sensor 240 is received, and in step SL11, it is confirmed whether maintenance can be performed. If it is "not possible," the process proceeds to step SL8, and if it is "possible," the process proceeds to step SL12 to perform maintenance. In this case, the pump is operated in step SL14. On the other hand, the print head 1 obtains the result of the placement detection of the print head 1 based on the output signal of the magnetic sensor 10b, and only when the AND condition between this placement detection signal and the maintenance execution permission signal is satisfied, the process proceeds to step SL15 to open the solvent injection valve.

[0240] In this modification 5, the valve can be controlled by the AND of the signals from the container detection sensor 235, the liquid volume sensor 240, and the placement detection, and the placement detection signal is not transmitted to the control unit 101. The cleaning control unit of this modification 5 can be configured to include an AND circuit for the print head 1.

[0241] <Sleep mode> In this embodiment, when the automatic printing system S is out of operation for a long period of time, the system is configured to be able to execute a sleep mode in which automatic cleaning is performed periodically to prevent problems caused by ink adhesion. As shown in FIG. 2, the control unit 101 of the controller 100 includes a mode operation unit 101b. The mode operation unit 101b is a part that operates a sleep mode for automatically performing a cleaning operation of the print head 1 at a predetermined interval during the outage of the inkjet recording apparatus I to which external power is supplied, when the placement detection unit (magnetic sensor 10b, light receiving element 10c, etc.) detects that the print head 1 has been placed on the cleaning placement unit 200. To operate the sleep mode, power is supplied to the inkjet recording apparatus I from, for example, a commercial power source 700, as shown in FIG. 2.

[0242] FIG. 42 is a flow chart showing an example of the operation of the sleep mode. This flow starts when it is detected that the print head 1 is placed on the cleaning placement unit 200 after power-down. When the flow starts, the mode operation unit 101b generates a maintenance user interface 400 shown in FIG. 43 and displays it on the display unit 103a shown in FIG. 2. The maintenance start user interface 400 is provided with a start button 400a that is operated when starting the sleep mode, and a display area 400b that displays an explanatory text and an explanatory diagram related to the sleep mode. When the start button 400a is pressed in step SM1 of FIG. 42, the mode operation unit 101b detects this and operates the sleep mode. In addition, the mode operation unit 101b generates a status display user interface 401 shown in FIG. 44 and displays it on the display unit 103a shown in FIG. 2. The status display user interface 401 is provided with a release button 401a that is operated when releasing (ending) the sleep mode, a status display area 401b that displays the remaining ink amount, etc., and a display area 401c that displays explanatory text and diagrams. During the sleep mode, the status display user interface 401 can be kept displayed.

[0243] Step SM2 in FIG. 42 shows a case where the inkjet recording apparatus I is left for a long period of time, from several weeks to several months. During this time, the cleaning operation unit 101a automatically starts up the inkjet recording apparatus I and performs a cleaning operation in which the solvent is supplied to the nozzle 12 by the solvent supply unit 105 and ejected from the nozzle 12. The cleaning operation may be, for example, a cleaning operation in which the solvent is sprayed from the cleaning nozzle 19, or a cleaning operation in which ink is supplied from the ink supply unit 104 to the nozzle and ejected from the nozzle. Two or more of these multiple cleaning operations may be performed. The nozzle for cleaning is not limited to the cleaning nozzle 19, and may be, for example, a cleaning agent nozzle 360 ​​provided on the cleaning placement unit 200, as shown by the virtual line in FIG. 24. The cleaning agent can be supplied to the cleaning agent nozzle 360 ​​from the controller 100 in the same manner as the cleaning nozzle 19. The cleaning agent nozzle 360 ​​can spray the cleaning agent onto the nozzle 12, the charging electrode 13, and the like.

[0244] 2, the control unit 101 of the controller 100 includes a time measurement unit 101c that measures the time during which the inkjet recording apparatus I is in the sleep mode operation. This time measurement unit 101c is a so-called timer, and can be configured to start timing when the start button 400a of the maintenance user interface 400 shown in FIG. 43 is pressed, or can be configured to start timing when the mode operation unit 101b operates the sleep mode.

[0245] When the cleaning operation unit 101a detects that the mode operation unit 101b has operated the sleep mode, the cleaning operation unit 101a acquires the time during the sleep mode operation measured by the time measurement unit 101c. When the time during the sleep mode operation measured by the time measurement unit 101c reaches a predetermined time, the cleaning operation unit 101a performs the cleaning operation.

[0246] In step SM3 shown in Fig. 42, when the release button 401a of the status display user interface 401 shown in Fig. 44 is pressed, the mode operation unit 101b detects this and releases the sleep mode. When the control unit 101 detects that the mode operation unit 101b has released the sleep mode, it executes the start-up process of step SM4, and then executes the print process of step SM5.

[0247] In the above example, a case has been described in which the sleep mode is operated without checking for any abnormalities on the cleaning placement section 200 side, but this is not limited to the above, and the sleep mode can also be operated while checking for any abnormalities on the cleaning placement section 200 side.

[0248] Fig. 45 is a flow chart for operating the sleep mode while checking for any abnormality on the cleaning placement unit 200 side. When the start button 400a shown in Fig. 43 is pressed in step SN1, the mode operation unit 101b detects this and activates the sleep mode. In step SN2, the time measurement unit 101c starts timing, and performs a process of adding "7 days" to the date and time when the inkjet recording apparatus I was shut down. This "7 days" is a period during which it is determined that a cleaning operation is necessary, and is not limited to "7 days". A process of adding time instead of the number of days may also be performed.

[0249] After waiting in step SN3, the process proceeds to step SN4, where it is determined whether or not a predetermined time has passed (the above-mentioned seven days in this example). If the determination in step SN4 is NO and seven days have not passed, the process proceeds to step SN3 and the process proceeds to step SN4 again. If the determination in step SN4 is YES and seven days have passed since the inkjet recording apparatus I was shut down, the process proceeds to step SN5, where an error release process is performed. Errors will be described later.

[0250] Then, the process proceeds to step SN6, where an abnormality detection determination is performed. Abnormality detection can be performed according to the flowchart shown in FIG. 31. That is, when the magnetic sensor 10b, which is the placement detection unit, is OFF, this means that the print head 1 is not in the correct position, and an abnormality is detected in step SN6 of FIG. 45. Also, when the container detection sensor 235 is OFF, this means that the collection container 300 is not attached, and an abnormality is detected in step SN6 of FIG. 45. Furthermore, when the liquid level sensor 240 is ON, this means that the cleaning agent in the collection container 300 is full or nearly full, and an abnormality is detected in step SN6 of FIG. 45.

[0251] The cleaning operation unit 101a is configured to execute a placement confirmation process in step SN6 to confirm whether or not the placement detection unit has detected that the print head 1 has been placed on the cleaning placement section 200 when the time during sleep mode operation has reached a predetermined time and before performing the cleaning operation.

[0252] If any one of the above multiple abnormalities is detected, the result is "abnormal" in step SN6, and the process proceeds to step SN7. In step SN7, an alert is output, an error screen is displayed on the display unit 103a or the like, and the error is recorded. In other words, the cleaning operation unit 101a is configured to output an error in step SN7 if it is determined that the placement detection unit has not detected that the print head 1 has been placed on the cleaning placement unit 200 as a result of the placement confirmation process in step SN6. The error output may be in the form of an error display on the display unit 103a, an error sound being generated from a speaker or the like (not shown), or an error signal being output to an external device.

[0253] If it is determined to be "normal" in step SN6, the process proceeds to step SN8, where the cleaning operation unit 101a performs the cleaning operation, thereby increasing the success rate of start-up.

[0254] Once the cleaning operation has started, the process proceeds to step SN9, where an abnormality detection determination is made similar to that of step SN6. In this step SN9, the cleaning operation unit 101a executes a placement confirmation process to confirm whether or not the placement detection unit has detected that the print head 1 has been placed on the cleaning placement unit 200 during the cleaning operation. If an "abnormality" is determined in step SN9, the process proceeds to step SN20, where the cleaning operation is urgently stopped, and then the process proceeds to step SN19. Therefore, the cleaning operation unit 101a is configured to stop the cleaning operation if it is determined, based on the result of the placement confirmation process in step SN9, that the placement detection unit has not detected that the print head 1 has been placed on the cleaning placement unit 200.

[0255] For example, as shown in FIG. 46, if the print head 1 is removed during the cleaning operation, the magnetic sensor 10b turns OFF and the cleaning operation is stopped urgently. Also, if the liquid level sensor 240 detects that cleaning agent has overflowed from the collection container 300 during the cleaning operation, the cleaning operation is stopped urgently. Also, if the container detection sensor 235 detects that the collection container 300 has been removed during the cleaning operation, the cleaning operation is stopped urgently.

[0256] If the result of the determination in step SN9 is "normal," the process proceeds to step SN10, where it is determined whether or not the cleaning operation has been completed. If the result of the determination in step SN10 is NO, where the cleaning operation has not been completed, the cleaning operation is continued. If the result of the determination in step SN10 is YES, where the cleaning operation has been completed, the process proceeds to step SN11, where the start-up process is executed. After the start-up process is executed, the process proceeds to step SN12, where an abnormality detection determination is performed similar to that in step SN6. If the result of the determination in step SN12 is "abnormal," the process proceeds to step SN18, where the stop-down process is executed immediately. If the result of the determination in step SN12 is "normal," the process proceeds to step SN13, where it is determined whether or not the start-up process has been completed. If the result of the determination in step SN13 is NO, where the start-up process has not been completed, the start-up process is continued. If the result of the determination in step SN13 is YES, where the start-up process has been completed, the process proceeds to step SN14, where the time measurement unit 101c starts measuring time anew, and a process of adding "7 days" to the current date and time is executed.

[0257] Thereafter, the process proceeds to step SN15, where the ink is circulated and the ink viscosity is adjusted to prevent ink adhesion. Next, the process proceeds to step SN16, where an abnormality detection determination is made similar to that of step SN6. If an "abnormal" is determined in step SN16, the process proceeds to step SN18, where the shutdown process is immediately executed. If a "normal" is determined in step SN16, the process proceeds to step SN17, where a determination is made as to whether or not a predetermined ink adjustment time has elapsed. If the adjustment time has not elapsed, step SN15 is continued.

[0258] If step SN17 returns YES and the ink adjustment time has elapsed, the process proceeds to step SN18, where a start-up process is executed. After that, the process proceeds to step SN19, where the inkjet recording apparatus I is stopped, and then the process proceeds to step SN3. In step SN5 that follows, the above-mentioned error is cleared.

[0259] <Sleep mode variation> Fig. 47 is a flowchart showing a modified sleep mode, which differs from the process shown in Fig. 45 in that this modified example can reduce the consumption of cleaning agent. Steps SP1 to SP7 are the same as steps SN1 to SN7 in the flowchart shown in Fig. 45. In step SP8, start-up processing is performed, and the process proceeds to step SP9. In step SP9, an abnormality detection determination is performed similarly to step SN6 in Fig. 45. Then, if an "abnormality" is determined in step SP9, the process proceeds to step SP21, where the start-up processing is urgently stopped, and then the process proceeds to step SP20.

[0260] If the result of step SP9 is "normal," the process proceeds to step SP10, where it is determined whether an error has been detected. This error is different from an error resulting from abnormality detection, and is an error that occurs when, for example, the nozzle 12 becomes clogged. If the result of step SP10 is "normal," the process proceeds to step SP11, where it is determined whether the start-up process has ended. If the result of step SP11 is NO, indicating that the start-up process has not ended, the start-up process continues.

[0261] On the other hand, if it is determined to be "abnormal" in step SP10, this means that there is a blockage in the nozzle 12, etc., and the cleaning operation is highly necessary, so the process proceeds to step SP12 and the cleaning operation is performed. In other words, in this modified example, the cleaning operation is performed only when it is determined that the cleaning operation is highly necessary, so that the consumption of cleaning agent can be reduced.

[0262] When the process proceeds from step SP12 to step SP13, an abnormality detection determination is performed in the same manner as in step SP9. If an "abnormal" is determined in step SP13, the process proceeds to step SP21, where the cleaning operation is stopped urgently, and then the process proceeds to step SP20. If a "normal" is determined in step SP13, the process proceeds to step SP14, where it is determined whether or not the cleaning operation has ended. If the determination in step SP14 is NO and the cleaning operation has not ended, the cleaning operation continues.

[0263] If the determination in step SP14 is YES and the cleaning operation is completed, the process proceeds to step SP15, where the timer unit 101c starts measuring time anew and adds "7 days" to the current date and time.

[0264] Thereafter, the process proceeds to step SP16, where the ink is circulated and the viscosity of the ink is adjusted. Next, the process proceeds to step SP17, where an abnormality detection determination is performed similar to that of step SP9. If the determination is "abnormal" in step SP17, the process proceeds to step SP19, where the tamping down process is immediately performed. If the determination is "normal" in step SP17, the process proceeds to step SP18, where it is determined whether the viscosity of the ink is within the normal viscosity range. If the determination is NO in step SP18, the viscosity is adjusted until the viscosity of the ink is within the normal viscosity range. If the determination is YES in step SN18, the process proceeds to step SN19, where the tamping down process is performed. Thereafter, the process proceeds to step SP20, where the inkjet recording apparatus I is stopped, and then the process proceeds to step SP3.

[0265] <Sleep mode transition judgment> The transition to the sleep mode may be made automatically after the falling edge processing, or after the falling edge processing, the mode operation unit 101b may generate a period selection user interface 402 shown in FIG. 48 and display this on the display unit 103a shown in FIG. 2, and whether or not to transition may be determined depending on the period selection result.

[0266] The user interface 402 for period selection shown in FIG. 48 is provided with an input section 402a for inputting information on the period from the stop of operation of the inkjet recording apparatus I to the next operation before the stop of operation, an OK button 402b, and a cancel button 402c. The input section 402a is provided with selection buttons for 6 days or less, 7 days or more, and 21 days or more as the period from the stop of operation of the inkjet recording apparatus I to the next operation, and the above period can be input by operating the selection button. Note that the number of days from the stop of operation of the inkjet recording apparatus I to the next operation may be input, in which case the input number of days becomes information on the period from the stop of operation to the next operation. Also, the date of the next operation may be input from, for example, a calendar, in which case the input date becomes information on the period from the stop of operation to the next operation. In either case, the period until the next operation can be obtained.

[0267] 49 is a flowchart showing an example of a sleep mode transition determination process. This flow starts with the start of a shutdown process after the printing process is completed by the inkjet recording apparatus I. The start of the shutdown process can be detected by the user's operation of a shutdown process start button (not shown).

[0268] In step SQ1, the period is determined based on information about the period entered in input section 402a of period selection user interface 402 shown in Fig. 48. If it is within six days, the process proceeds to step SQ2, where normal shutdown processing is performed. If it is seven days or more, the process proceeds to step SQ3, where long-term shutdown processing is performed. In long-term shutdown processing, the cleaning agent discharge time is set longer than in normal shutdown processing, the cleaning agent discharge amount is set to be larger, or the cleaning agent is discharged more frequently.

[0269] If the result of the period determination in step SQ1 is 21 days or more, the process proceeds to step SQ4. In step SQ4, a communication check is performed between the controller 100 and the cleaning mount unit 200. If the check results in that the controller 100 and the cleaning mount unit 200 are not connected, the process proceeds to step SQ3. If the controller 100 and the cleaning mount unit 200 are connected, the process proceeds to step SQ5, where the maintenance user interface 400 shown in FIG. 43 is displayed on the display unit 103a shown in FIG. 2. If the start button 400a is pressed in step SQ6, the mode operation unit 101b detects this, activates the sleep mode, and proceeds to step SQ7. In step SQ7, a placement check process is performed to check whether the placement detection unit has detected that the print head 1 has been placed on the cleaning mount unit 200.

[0270] If the determination in step SQ7 is "not placed" and the print head 1 is not placed on the cleaning placement section 200, the process proceeds to step SQ8, where an alert is output and displayed on the display section 103a. On the other hand, if the determination in step SQ7 is "placed", the process proceeds to step SQ9, where a shutdown process is performed, and then the mode operation section 101b activates the sleep mode. Therefore, the mode operation section 101b is configured to determine in step SQ1 whether the period until the next operation is a predetermined period or more based on information regarding the period input to the input section 402a of the period selection user interface 402 shown in FIG. 48, and to activate the sleep mode after proceeding to steps SQ4 to SQ7 and SQ7 if it is determined that the period until the next operation is the predetermined period or more, so that maintenance according to the operation suspension period can be automatically performed. On the other hand, if it is determined that the period until the next operation is less than the predetermined period, the process proceeds to step SQ2 or SQ3, and the mode operation section 101b does not activate the sleep mode.

[0271] <Automatic sleep mode transition> FIG. 50 is a flow chart showing an example of a sleep mode automatic transition determination process. This flow starts when it is detected that the print head 1 has been placed on the cleaning placement section 200. In step SR1, it is determined whether or not each pump of the controller 100 is stopped. If the determination in step SR1 is NO, it is considered that the pump is in operation, so the process proceeds to step SR2, where the operation date and time are updated and stored. If the pump is operating during operation, that is, when a printing process is being performed, the operation date and time are updated and rewritten as necessary. On the other hand, if the determination in step SR1 is YES, the process proceeds to step SR3, where the unused period is calculated. The unused period is obtained by subtracting the operation date and time from the current date and time.

[0272] In step SR4, the mode operation unit 101b judges whether the unused period is longer than a specified number of days. The specified number of days can be set to, for example, several weeks, but in this embodiment, it is set to 21 days. If the result of step SR4 is NO and the unused period does not reach the specified number of days, the process returns to step SR1, whereas if the result of step SR4 is YES and the unused period is longer than the specified number of days, the mode operation unit 101b operates the sleep mode.

[0273] In this example, the inkjet recording system S automatically determines whether or not to enter sleep mode based on the period of time the inkjet recording system S has been left unused, without displaying the period selection user interface 402 shown in FIG. 48, and enters sleep mode if necessary. Therefore, even if the user forgets to set the system to sleep mode, a cleaning operation can be performed.

[0274] (Effects of the embodiment) As described above, according to this embodiment, when the print head 1 is placed on the cleaning platform 200, it can be detected that the print head 1 has been placed on the cleaning platform 200. A signal based on confirmation that the print head 1 has been placed on the cleaning platform 200 is then sent to the controller 100 which is connected to the print head 1 placed on the cleaning platform 200. As a result, the controller 100 can confirm that the print head 1 connected to it is placed on the cleaning platform 200, and can determine that the print head 1 is in a state where it can be cleaned. Therefore, the print head 1 placed on the cleaning platform 200 can be cleaned, and cleaning liquid leaking from the print head 1 can be received by the cleaning platform 200, preventing contamination of the surrounding environment.

[0275] Furthermore, the mode operation unit 101b can operate the sleep mode while the inkjet recording apparatus I is out of operation. When the time during operation in the sleep mode reaches a predetermined time, the cleaning operation unit 101a automatically starts up the inkjet recording apparatus I and performs a cleaning operation. This makes it less likely that problems caused by ink adhesion will occur when the inkjet recording apparatus I is expected to be stored for a long period of time before being restarted.

[0276] The above-described embodiment is merely illustrative in all respects and should not be construed as limiting. Furthermore, all modifications and variations within the scope of the claims are within the scope of the present invention. [Industrial Applicability]

[0277] As described above, the present invention can be used, for example, when printing on various types of workpieces. [Explanation of symbols]

[0278] 1 Print Head 10b Magnetic sensor 10c Photodetector 12 Nozzles 13 Charged electrode 15 Deflection electrode 100 Controller 101 Control section 101a Cleaning operation unit 101b Mode operation section 101c Time measurement section 104 Ink supply unit 105 Solvent supply section 200 Cleaning placement section 211a magnet 211c Light emitting element 212 Bottom wall 212b Passing hole 213 Peripheral wall section 235 Container detection sensor 240 Liquid level sensor 300 Collection container I Inkjet recording device S Inkjet recording system

Claims

1. a continuous ink jet recording device having a controller and a print head that is electrically and fluidly connected to the controller via a connection cable and that is installed outside the controller; a cleaning platform on which the print head is set when the print head is cleaned with a solvent; and a recovery container attached to the cleaning placement portion for recovering a solvent; a container detection unit that detects that the collection container is attached to the cleaning placement unit and outputs a signal to the controller; a cleaning operation unit that is provided in the controller of the inkjet recording device, automatically performs a cleaning operation of the print head, and stops the cleaning operation when the container detection unit detects that the collection container has been removed during the cleaning operation based on a signal output by the container detection unit; having The cleaning operation unit performs, as the cleaning operation, a first cleaning operation that is started in response to a user's operation input, and a second cleaning operation that is started based on a determination of a period during which the inkjet recording device is stopped.

2. 2. The inkjet recording system according to claim 1, wherein the cleaning operation unit automatically performs the cleaning operation of the print head when the attachment of the collection container to the cleaning mount unit is detected by the container detection unit.

3. The inkjet recording apparatus further comprises: an operation display unit that is provided in the controller and that receives operation inputs from a user and displays various information; 3. The inkjet recording system according to claim 1, wherein the operation display unit displays an error screen when the container detection unit detects removal of the collection container during the cleaning operation by the cleaning operation unit.

4. the operation display unit accepts an input of a number of days from a user; The inkjet recording system according to claim 3 , wherein the cleaning operation unit automatically performs a cleaning operation of the print head during a period when the inkjet recording device is not in operation, in accordance with the number of days that have elapsed that are received via the operation display unit.

5. The inkjet recording apparatus further comprises: a mode operation unit that operates a sleep mode in which the cleaning operation unit automatically performs a cleaning operation of the print head while the inkjet recording device is not in operation, 5. The inkjet printing system according to claim 3, wherein the mode operation unit activates the sleep mode based on an operation input from a user received by the operation display unit.

6. 6. The inkjet printing system according to claim 5, wherein the operation display unit displays an explanatory text about the sleep mode during operation in the sleep mode, and receives an operation input for canceling the sleep mode.

7. 7. The inkjet recording system according to claim 1, wherein the container detection section is provided on the cleaning mount section and has a magnetic sensor that detects the attachment of the collection container by magnetic force.

8. The cleaning operation unit performs the following as a cleaning operation for the print head:

8. The inkjet recording system according to claim 1, further comprising at least one of a first operation of ejecting a solvent from a nozzle, a second operation of ejecting a solvent from a cleaning nozzle that is different from the nozzle and is provided on the print head or the cleaning placement section, and a third operation of ejecting ink from the nozzle.

9. The inkjet recording system further comprises:

9. The ink jet recording system according to claim 1, further comprising a liquid amount detector that detects the amount of liquid in the recovery container.

10. 10. The ink jet recording system according to claim 9, wherein the liquid amount detection unit has a float sensor that detects the height of the liquid surface in the recovery container.

11. The inkjet recording system further comprises:

11. The inkjet recording system according to claim 1, further comprising a placement detector that detects that the print head is placed on the cleaning placement section.

12. the print head comprises a nozzle for ejecting ink, a charging electrode for charging ink droplets ejected from the nozzle, a deflection electrode for deflecting the ink droplets charged by the charging electrode, and a gutter for collecting the ink droplets not deflected by the deflection electrode; the controller has an ink supply unit that supplies ink to the print head and a solvent supply unit that supplies a solvent to the print head; 2. The inkjet recording system according to claim 1, wherein the cleaning operation unit automatically performs a cleaning operation of the print head using the solvent supplied from the solvent supply unit.

Images