Liquid processing device, control device and program

Abstract

To provide a liquid circulation device, a control device and a program that can improve printing efficiency.SOLUTION: A liquid circulation device includes: a circuit which is communicated to a liquid discharge head for discharging liquid and through which the liquid flows; and a controller for stopping circulation operation of circulating the liquid when the pressure of the circuit is outside the normal range.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] An embodiment of the present invention relates to a liquid treatment device, a control device, and a program. [Background technology]

[0002] A liquid ejection device is known that includes a liquid ejection head that ejects liquid, and a liquid processing device such as a liquid circulation device that circulates the liquid in a circulation path including the liquid ejection head. In such a liquid ejection device, the pressure in the circulation path is detected and pressure adjustment is performed to maintain the meniscus of the nozzle.

[0003] In such a liquid processing apparatus, if a problem occurs in the pressure control, the connected liquid ejection head cannot eject and print properly, resulting in poor images and reduced printing efficiency. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 11-188864 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a liquid treatment device, a control device, and a program that can improve printing efficiency. [Means for solving the problem]

[0006] A liquid treatment device according to an embodiment includes a flow path through which liquid flows that is connected to a liquid ejection head that ejects liquid, and a control unit that stops the flow of the liquid when the pressure in the flow path is outside the normal range.

[0007] A control device according to another embodiment includes a control unit that is in communication with a liquid ejection head that ejects liquid and that stops the operation of flowing the liquid when the pressure in a flow path through which the liquid flows is outside a normal range.

[0008] A program according to another embodiment enables a computer used in a liquid processing device having a flow path through which liquid flows and connected to a liquid ejection head to realize the function of stopping the flow of liquid when the pressure value of the flow path is not within a normal range. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is an explanatory diagram showing the configuration of an inkjet recording apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a block diagram showing the configuration of a control system of the inkjet printing apparatus. [Diagram 3] 4 is a flowchart showing a control method of the inkjet recording apparatus. [Figure 4] FIG. 4 is an explanatory diagram showing a display example of a part of a screen of a display device of the inkjet recording apparatus. [Diagram 5] FIG. 4 is an explanatory diagram showing a display example of a part of a screen of a display device of the inkjet recording apparatus. [Figure 6] FIG. 11 is an explanatory diagram showing the configuration of an inkjet recording apparatus according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [First embodiment] An inkjet recording apparatus 1 as a printing apparatus and a liquid ejection apparatus 10 as a liquid circulation apparatus (liquid processing apparatus) according to a first embodiment will be described below with reference to Figs. 1 to 5. In each drawing, the configuration is enlarged, reduced or omitted as appropriate for the purpose of explanation. Fig. 1 is an explanatory diagram showing the configuration of the inkjet recording apparatus 1. Fig. 2 is a block diagram showing the configuration of a control unit of the inkjet recording apparatus 1. Fig. 3 is a flowchart showing a control method of the inkjet recording apparatus 1, and Figs. 4 and 5 are explanatory diagrams showing examples of displays on the display screen of a display device 16 of the inkjet recording apparatus 1.

[0011] 1 includes a liquid ejection device 10, a host control unit 13 (control device) connected to the liquid ejection device 10, a power source 14, an input device 15, a display device 16, and a buzzer 17. The inkjet recording device 1 also includes a head support mechanism that movably supports the liquid ejection device 10, and a medium support mechanism that movably supports a recording medium S.

[0012] The liquid ejection device 10 includes a liquid ejection head 20 and a circulation device 30 serving as a liquid treatment device. The liquid ejection device 10 ejects a liquid, such as ink I, from the liquid ejection head 20 to form a desired image on a recording medium S disposed opposite the liquid ejection head 20.

[0013] For example, one or more liquid ejection devices 10 may be provided. As an example, multiple liquid ejection devices having the same configuration may be provided. The multiple liquid ejection devices 10 eject ink of different colors, such as cyan ink, magenta ink, yellow ink, black ink, and white ink, onto the medium S to form a desired image. Note that the colors or characteristics of the inks used are not limited.

[0014] The liquid ejection head 20 is an inkjet head equipped with a plurality of nozzles 21 and a manifold 22 that forms a predetermined ink flow path having a plurality of ink pressure chambers that communicate with the plurality of nozzles 21. The plurality of ink pressure chambers are provided with actuators that are connected to a drive circuit. The liquid ejection head 20 ejects liquid from the corresponding nozzles 21 by the actuators deforming in response to a voltage.

[0015] The circulation device 30 includes a circulation path 31, which is a predetermined ink path configured to allow liquid to circulate through the liquid ejection head 20, and a cartridge 32, a first pump 33, a first tank 34, a bypass tank 35, a second tank 36, a second pump 37, and a module control unit 38 (control device), which are provided in this circulation path 31 in this order. For example, the circulation device 30 is configured by connecting the cartridge 32 to a circulation head 300 that contains the first pump 33, the first tank 34, the bypass tank 35, the second tank 36, the second pump 37, and the module control unit 38 in a case 301 and configures a circulation flow path therein.

[0016] The circulation path 31 is a flow path that communicates with the liquid ejection head 20 and through which liquid flows. The circulation path 31 is configured, for example, by a pipe made of a metal or resin material, or a tube covering the outer surface of the pipe, and forms a predetermined flow path inside. The circulation path 31 has an upstream first flow path 311 that passes from the cartridge 32 through an upstream first tank 34 to a supply port 201 of the liquid ejection head 20, a downstream second flow path 312 that passes from a recovery port 202 of the liquid ejection head 20 through a second tank 36 to the cartridge 32, and a bypass flow path 313 that connects the first flow path 311 and the second flow path 312.

[0017] The bypass flow path 313 is a flow path that connects the first flow path 311 and the second flow path 312. The bypass flow path 313 short-circuits the primary side of the liquid ejection head 20 in the circulation path 31 and the secondary side of the liquid ejection head 20 without passing through the liquid ejection head 20. The bypass tank 35 is connected to the bypass flow path 313. That is, the bypass flow path 313 includes a first bypass flow path 3131 that connects the bypass tank 35 and the first flow path 311, and a second bypass flow path 3132 that connects the bypass tank 35 and the second flow path 312.

[0018] The cartridge 32 is configured to be capable of holding the ink I. An air chamber formed inside the cartridge 32 is open to the atmosphere. The cartridge 32 is connected to a first tank 34 via a first flow path 311 in which a first pump 33 is provided.

[0019] The first pump 33 is provided in a first flow path 311 that is a flow path between the cartridge 32 and the first tank , and sends the ink I held in the cartridge 32 toward the first tank .

[0020] The first tank 34 is configured to be able to store liquid. The first tank 34 is connected to the primary side of the liquid ejection head 20 by the circulation path 31. For example, the first tank 34 is provided with a liquid level sensor 54 that detects the liquid level position in the first tank 34. The liquid level sensor 54 detects the amount of ink in the first tank 34 and sends the detected data to the module control unit 38.

[0021] The bypass tank 35 is provided in the bypass flow path 313. The bypass tank 35 has a flow path cross-sectional area larger than the flow path cross-sectional area of ​​the bypass flow path 313, and is configured to be able to store liquid. The bypass tank 35 has, for example, an upper wall, a lower wall, a rear wall, a front wall, and a pair of left and right side walls, and is configured in a rectangular box shape that forms a storage chamber for storing liquid therein. The bypass flow paths 313 are connected to the pair of side walls of the bypass tank 35, respectively.

[0022] Ink flowing through the bypass flow path 313 is disposed in a lower region of the storage chamber in the bypass tank 35, and an air chamber is formed in an upper region of the storage chamber. The bypass tank 35 is capable of storing a predetermined amount of liquid and air. In this embodiment, for example, the connection position of the first bypass flow path 3131 on the inflow side to the bypass tank 35 and the connection position of the second bypass flow path 3132 on the outflow side to the bypass tank 35 are set at the same height.

[0023] An on-off valve 41 configured to be able to be opened to the atmosphere is connected to the air chamber of the bypass tank 35. That is, a connecting pipe 355 extending upward is provided on the upper wall of the bypass tank 35, and the on-off valve 41 for opening and closing the flow path in the connecting pipe 355 is provided on the other end of the connecting pipe 355.

[0024] As an example, in this embodiment, the bypass tank 35 is provided at the midpoint of the bypass flow path 313, and the first bypass flow path 3131 and the second bypass flow path 3132 have the same pipe length and pipe diameter. In addition, in the circulation path 31, the distance from the branching point where the bypass flow path 313 of the first flow path 311 branches to the supply port 201 of the liquid ejection head 20 is the same as the distance from the recovery port 202 of the liquid ejection head 20 to the junction point with the second bypass flow path 3132 of the second flow path 312. The pressure in the circulation path 31 is higher on the primary side, i.e., the inflow side, of the liquid ejection head 20 than on the secondary side, i.e., the outflow side, of the liquid ejection head 20 due to pressure loss caused by the resistance of the liquid ejection head 20. Therefore, in the circulation path 31 and the bypass flow path 313, the liquid flows from the primary side, which has a higher pressure, to the secondary side, which has a lower pressure.

[0025] The second tank 36 is configured to be able to store liquid. The second tank 36 is connected to the secondary side of the liquid ejection head 20 by the circulation path 31. For example, the second tank 36 is provided with a liquid level sensor 55 that detects the liquid level position in the second tank 36. The liquid level sensor 55 detects the amount of ink in the second tank 36 and sends the detected data to the module control unit 38.

[0026] The second pump 37 is provided in the second flow path 312 and is a recovery pump that sends the liquid to the cartridge 32 side.

[0027] The second pump 37 is provided in the second flow path 312 of the circulation path 31. The second pump 37 pumps the liquid from the second tank 36 toward the cartridge 32.

[0028] The second pump 37 and the first pump 33 are configured by, for example, a piezoelectric pump. Note that, for example, a tube pump, a diaphragm pump, or a piston pump may be used as the second pump 37 and the first pump 33. For example, the first pump 33 and the second pump 37 are a pressure adjustment mechanism that adjusts the pressure in the circulation path 31 and adjusts the ink pressure in the nozzles 21.

[0029] The pressure sensor 39 is a pressure detection unit (pressure detector) that detects the pressure of the circulation path 31. For example, the pressure sensor 39 is provided in one of the circulation paths 31 and detects the pressure in the circulation path 31. For example, in this embodiment, the pressure sensor 39 is provided in the bypass tank 35 and detects the pressure of an air chamber (air chamber) in the bypass tank 35. The pressure sensor 39 may detect the pressure of other parts of the circulation path 31, and may detect the pressure in each part of the circulation path 31, for example, various tanks including the cartridge, flow paths, or in the liquid ejection head 20. The pressure sensor 39 outputs the pressure as an electric signal using, for example, a semiconductor piezoresistance pressure sensor. The semiconductor piezoresistance pressure sensor includes a diaphragm that receives pressure from the outside and a semiconductor strain gauge formed on the surface of the diaphragm. The semiconductor piezoresistance pressure sensor detects the pressure by converting the change in electrical resistance caused by the piezoresistance effect that occurs in the strain gauge as the diaphragm deforms due to the pressure from the outside into an electric signal, and sends the detected data to the module control unit 38.

[0030] The on-off valve 41 is configured to be able to open and close the air chamber of the bypass tank 35 to the atmosphere. The on-off valve 41 is opened when the pressure sensor 39 connected to the bypass tank 35 is calibrated.

[0031] The input device 15 is an input device that includes function keys such as a power key, a paper feed key, an error release key, etc. For example, the input device 15 is a keyboard and a touch panel provided on a computer terminal having the host control unit 13.

[0032] The display device 16 has a display unit that displays various information about the image printing device. The display device 16 is a display provided in a computer terminal having the host control unit 13.

[0033] The buzzer 17 generates a sound. The buzzer 17 is, for example, a piezoelectric buzzer that is mounted on a control board of the module control unit 38 and generates a sound when a voltage is applied thereto.

[0034] In addition, in the circulation device 30, a filter that removes impurities from the ink I is provided at a predetermined position in the circulation path 31. In addition, in the circulation device 30, a heater device 43 that adjusts the temperature of the ink I is provided at a predetermined position in the circulation path 31.

[0035] The circulation device 30 may further include, as an adjustment mechanism, an opening / closing mechanism for opening / closing the air chambers in the first tank 34 and the second tank 36 to the atmosphere, and an adjustment mechanism for pressurizing and depressurizing the first tank 34 and the second tank 36. The adjustment mechanism adjusts the pressure in the circulation path 31 and the ink pressure in the nozzles 21 by opening the first tank 34 and the second tank 36 to the atmosphere and pressurizing and depressurizing the second tank 36 under the control of the host control unit 13 and the module control unit 38.

[0036] Next, a control system for controlling the operation of the inkjet recording apparatus 1 will be described with reference to Fig. 2. The control system of the inkjet recording apparatus 1 according to this embodiment includes a host control unit 13 (control device) and a module control unit 38 (control device).

[0037] The host control unit 13 of the inkjet recording apparatus 1 is connected to a power source 14, an input device 15, and a display device 16. The host control unit 13 is provided in a computer terminal (computer) 130 equipped with the display device 16 and the input device 15, for example.

[0038] The host control unit 13 includes a CPU 131 (control unit), a drive circuit for driving each element, a storage unit 132 for storing various data, and a communication unit 133 for communication.

[0039] The CPU 131 corresponds to the core of the host control unit 13. The CPU 131 has a processing circuit that controls each unit to realize various functions of the liquid ejection device according to various programs including an operating system and application programs. The CPU 131 detects input information input to the input device 15 as an instruction.

[0040] The CPU 131 instructs the module control unit 38 on control programs and operating conditions by sending operating conditions to the module control unit 38 in accordance with various operating conditions and various programs input by the user to the input device 15 or pre-stored in the memory unit 132.

[0041] In other words, by the processor executing control processing based on the control program, the host control unit 13, with the processor as its central part, functions as a printing means, a moving means, a display means, an instruction means, and a pressure adjustment means that control the printing operation, the moving operation, the display operation, the instruction operation, and the pressure adjustment operation.

[0042] The storage unit 132 includes, for example, a program memory and a RAM. Application programs and various setting values ​​are stored in the storage unit 132. For example, as control data used for pressure control, the storage unit 132 stores a calculation formula for calculating the ink pressure of the nozzles 21, and various setting values ​​such as a target pressure value, a normal range, an abnormal pressure value, and an adjusted maximum value for each pump.

[0043] For example, one of the programs stored in the storage unit 132 includes a program that causes the computer to realize a function of stopping a circulating operation that circulates liquid when the pressure value of the circulation path 31 is not within a normal range. The circulating operation is an operation of causing liquid to flow.

[0044] The communication unit 133 performs data communication with the module control unit 38 via a signal line such as a USB cable or via wireless LAN. The communication unit 133 has a communication interface for performing data communication. For example, the communication interface is a network interface.

[0045] The module control unit 38 includes a control board 70 mounted on the circulation device 30, a CPU 71 (control unit), a memory unit 72 that stores drive circuits for driving each element and various data, and a communication unit 73 for communicating with the host control unit 13 provided externally. The memory unit 72 is configured to include, for example, a program memory and a RAM. In addition, a buzzer 17 is mounted on the control board 70 of the module control unit 38.

[0046] The module control unit 38, while connected to the host control unit 13 via the communication unit 73, communicates with the host control unit 13 to receive various information such as operating conditions.

[0047] An input operation by a user or an instruction from the host control unit 13 of the inkjet recording apparatus 1 is transmitted to the CPU 71 of the module control unit 38 by the communication unit 73. In addition, various information acquired by the module control unit 38 is transmitted to the PC application or the host control unit 13 of the inkjet recording apparatus 1 via the communication unit 73.

[0048] The CPU 71 corresponds to the central portion of the module control unit 38. The CPU 71 has a processing circuit that controls each unit to realize various functions of the liquid ejection device according to an operating system and application programs.

[0049] The CPU 71 is connected to drive circuits 751, 752, 753, 754 for the first pump 33, second pump 37 and opening / closing valve 41 of the circulation device 30, the pressure sensor 39, a drive circuit 755 for the liquid ejection head 20, and a drive circuit 756 for the buzzer 17.

[0050] For example, the CPU 71 controls the operations of the first pump 33 and the second pump 37 based on commands from the host control unit 13, thereby functioning as a circulation unit that circulates the ink.

[0051] In addition, the CPU 71 functions as a supply unit that supplies ink from the cartridge 32 to the circulation path 31 by controlling the operations of the first pump 33 and the second pump 37 based on commands from the host control unit 13 .

[0052] Furthermore, the CPU 71 functions as a pressure adjusting means for adjusting the pressure of the ink in the nozzles 21 by controlling the operation of each pump 33, 37 based on information detected by the pressure sensor 39 or based on commands from the host control unit 13.

[0053] The storage unit 72 includes, for example, a program memory and a RAM. Various programs and various setting values ​​are stored in the storage unit 72. For example, as control data used for pressure control, the storage unit 72 stores a calculation formula for calculating the ink pressure of the nozzles 21, and various setting values ​​such as a target pressure value, a normal range, an abnormal pressure value, and an adjusted maximum value for each pump.

[0054] The communication unit 73 performs data communication with the host control unit 13 via a signal line such as a USB cable or via a wireless LAN. The communication unit 73 has a communication interface for performing data communication. For example, the communication interface is a network interface.

[0055] The control process and control program of the liquid ejection device 10 according to this embodiment will be described below with reference to the flowchart in Fig. 3. For example, the host control unit 13 and the module control unit 38 as control devices execute the control process of the terminal by operating according to various programs stored in the storage unit 132. For example, the inkjet recording device 1 performs liquid ejection process including the ink circulation operation in the circulation device 30, the liquid ejection operation in the liquid ejection head 20, and the medium transport operation.

[0056] For example, one of the various programs stored in the storage units 132, 72 includes a control program for causing the circulation device 30 to perform processing for stopping the circulation operation and processing for issuing a notification when the pressure in the circulation path 31 is outside the normal range.

[0057] For example, in this embodiment, as an example, an example is shown in which the circulation device 30 has both a host control unit 13 and a module control unit 38, and the module control unit 38 controls the circulation device 30 based on a signal sent from the host control unit 13, which is provided outside the circulation device 30, to the module control unit 38 of the circulation device 30. However, this is not limited to this, and the circulation device 30 may be controlled by only one of the two units.

[0058] When the CPU 131 detects an instruction to start circulation in Act 1 (Yes in Act 1), it starts the circulation process (Act 2). As a specific example, a print start button is displayed on the first display unit 161, which is part of the display screen of the display device 16, and the user inputs a command to start printing by operating the input device 15 while viewing the first display unit 161. Then, when the CPU 131 detects that the user has input an instruction to start printing (Yes in Act 1), it starts a liquid ejection process including an ink circulation operation in the circulation device 30, a liquid ejection operation in the liquid ejection head 20, and a medium transport operation. Specifically, the CPU 131 sends a command to the module control unit 38 to start the liquid ejection process including the ink circulation operation, the liquid ejection operation, and the medium transport operation.

[0059] When the CPU 71 receives a command from the CPU 131, it drives the first pump 33 and the second pump 37 to start the ink circulation operation in the circulation path 31. The CPU 71 also sends an image signal corresponding to the image data to the drive circuit 755 of the liquid ejection head 20, and selectively drives the actuators of the liquid ejection head 20 to eject ink droplets from the nozzles 21 onto the recording medium S. The CPU 71 also performs a printing operation to form an image on the recording medium S by performing an ink ejection operation while moving the liquid ejection device 10 back and forth in a direction perpendicular to the transport direction of the recording medium S.

[0060] Here, the ink I in the first flow path 311 is distributed to the liquid flowing to the liquid ejection head 20 and the liquid flowing to the bypass tank 35 via the bypass flow path 313 in a distribution according to the pipe resistance of the bypass flow path 313 and the bypass tank 35. That is, a part of the ink I circulates from the first tank 34 through the first flow path 311 to the liquid ejection head 20, through the second flow path 312 to the second tank 36, and flows back into the first tank 34. The remaining part of the ink I is sent from the first flow path 311 through the bypass flow path 313 and the bypass tank 35 to the second flow path 312 without passing through the liquid ejection head 20, and flows back into the first tank 34 through the second tank 36. By this circulation operation, impurities contained in the ink I are removed by a filter provided in the circulation path 31.

[0061] During printing operation, the CPU 131 drives the pumps 33, 37 and other pressure adjustment mechanisms to maintain the ink pressure Pn of the nozzle 21 at an appropriate value, thereby maintaining a negative pressure that prevents ink I from leaking from the nozzle 21 of the liquid ejection head 20 and prevents air bubbles from being sucked into the nozzle 21, thereby maintaining the meniscus.

[0062] The CPU 131, 71 may adjust the liquid level during the circulation process. For example, the CPU 131, 71 controls the first pump 33 and the second pump 37 based on the detection results of the liquid level sensors 54, 55 to supply ink from the cartridge 32 and adjust the liquid level position to an appropriate range. The CPU 131, 71 may also adjust the temperature by controlling the heater device 43 during the circulation process.

[0063] During circulation, the CPU 131 detects the ink pressure of the nozzle 21 at a predetermined timing based on the detection value from the pressure sensor 39 (Act 3). Specifically, based on the pressure data of the bypass tank 35 transmitted from the pressure sensor 39, the CPU 131 calculates the ink pressure of the nozzle 21 using a predetermined arithmetic expression.

[0064] For example, since the pressure detected in the bypass tank 35 is the average value of the ink pressure value Ph in the first flow path 311 and the ink pressure value Pl in the second flow path 312, the ink pressure Pn in the nozzle 21 can be obtained by adding the pressure ρgh generated by the water head difference between the height of the pressure measurement point and the height of the nozzle face to this pressure value in the bypass tank 35. Here, ρ is the density of the ink, g is the acceleration of gravity, and h is the distance in the height direction between the pressure measurement point and the nozzle face.

[0065] For example, the CPU 131 executes a control program to determine whether the calculated ink pressure Pn of the nozzle 21 is abnormal. For example, the CPU 131 determines whether the pressure value of the nozzle 21 calculated from the pressure value is within a predetermined or set normal range (Act 4). If the pressure value is an abnormal value that is outside the preset normal range (Yes in Act 4), the CPU 131 controls the pumps 33, 37, the opening / closing valve 41, etc. to stop the circulation operation (Act 6) and perform a notification process (Act 7).

[0066] For example, the CPU 131 waits for a predetermined time or until a predetermined condition is satisfied in Act 5, and then performs stop control and notification processing. That is, for example, after the start of circulation or when the target pressure is changed, the CPU 131 waits until a predetermined time has passed, or until the pressure reaches a value close to the target pressure value, for example, the target ±0.01 kPa, when the target pressure value is changed. Then, after the predetermined time has passed, and the pressure is in a stable state, the CPU 131 performs stop control in Act 6 or notification processing in Act 7. That is, the CPU 131 does not perform stop control or notification processing for a predetermined time after the start of circulation or a predetermined time after the target pressure is changed.

[0067] For example, the abnormal pressure value is determined by the target pressure value. FIG. 4 is an example of a screen of the display device 16. As shown in FIG. 4, the first display unit 161 having a setting screen of the display device 16 displays various conditions of one or more liquid ejection devices 10, operation buttons, status, etc. For example, the first display unit 161 displays various information such as the actual measurement value of the pressure sensor 39 and the pressure of the nozzle 21 calculated from the actual measurement value on the same screen as the target pressure. For example, the user operates the input device 15 while viewing the first display unit 161 of the display device 16 to input instructions for various operations, input and set the target pressure and various conditions. Then, the CPU 131 performs various controls according to the input. For example, a range for the target pressure is set in advance, and the CPU 131 determines a normal range of pressure control based on the input and set target value and based on the preset range, and treats pressure outside the normal range as an abnormal pressure value as an error target. For example, CPU 131 determines a range where the difference from the target value is within a predetermined value as the normal range, and sets a pressure value outside this normal range as an abnormal pressure value where some abnormality has occurred in the pressure control. As a specific example, when the target pressure is set to -1.00 kPa as shown in Fig. 4, if the range is set to plus or minus 0.1 kPa, the range from -1.1 kPa to -0.9 Pa is the normal range, and values ​​less than -1.1 kPa or greater than -0.9 kPa are determined to be abnormal pressure values.

[0068] For example, the pressure value becomes abnormal when there is a malfunction in pressure control if ink circulation is started with incomplete ink filling, if ink is consumed and the cartridge becomes empty, if the target pressure is set to an extremely negative pressure and air flows in from the nozzle 21, if ink becomes clogged somewhere in the circulation path 31, if ink leaks somewhere in the circulation path 31, etc. Therefore, when the pressure value during ink circulation becomes abnormal, the CPU 131 determines that a malfunction has occurred in the pressure control, automatically stops the ink circulation and performs a notification process.

[0069] In other words, the CPU 131 defines a pressure value within a certain range from the target pressure as a normal pressure value, and defines a range in which the difference from the target pressure is greater than a predetermined value as an abnormal pressure value.If the nozzle pressure value calculated by actual measurement falls outside the normal range and becomes an abnormal value (Yes in Act 4), the circulation operation is stopped (Act 6) and the device is put into standby mode.

[0070] As the circulation stop processing of Act 6, the CPU 131 outputs a command to the module control unit 38 to stop the first pump 33 and the second pump 37 and turn off (close) the opening and closing valve 41. Then, when the CPU 71 of the module control unit 38 receives a circulation stop command from the host control unit 13, it stops the circulation processing. For example, the circulation stop control is an infinite loop until a command to cancel the circulation command is received. In other words, the CPU 71 stops the circulation until a command to cancel the circulation command is received from the host control unit 13.

[0071] Furthermore, the CPU 131 performs a notification process during the infinite loop of the circulatory stop (Act 7). For example, as the notification process, the CPU 131 outputs a command to the module control unit 38 to perform the notification process.

[0072] When the CPU 71 receives a command for notification processing, it applies a voltage to the buzzer 17 to generate a buzzer sound and displays a message on the display device 16 to notify the user visually and audibly, thereby urging them to take action such as maintenance.

[0073] As an example of control of the notification process in the CPU 71, for example, the buzzer task does not sleep, but continues to run in cycles of 500 us or 100 ms, and when it receives a buzzer-on command from the host control unit 13, it waits for 500 μs, then inverts the buzzer port output and sounds the buzzer. At this time, for example, the frequency is set to a pleasant tone that is not harsh to the ear. On the other hand, if there is no buzzer-on command from the host control unit 13, it waits for the command in cycles of 100 ms.

[0074] Furthermore, as a display process in the notification process, the CPU 71 displays a message box including a message for the user on the second display unit 162, which is a part of the display screen, as shown in Fig. 5. For example, the CPU 71 also displays, in the message box, the identification of the liquid ejection device 10 in which an abnormality has occurred, such as "Ink1" in Fig. 5. For example, the CPU 71 displays, in the message box, the message "Circulation has been stopped as an abnormality has been detected," along with an "OK" button.

[0075] Thereafter, the CPU 71 continues the notification process until it detects a command to end the notification process (Act 8). For example, the user inputs the notification end command by operating the input device 15 to click the "OK" button in a message box on the second display unit 162 of the display screen. When the CPU 131 detects the command to end the notification process, it outputs a command to end the notification to the module control unit 38 (Act 9). Then, when the CPU 71 receives the command to end the notification process, it stops the buzzer 17 and ends the display on the display box 151, thereby ending the notification process.

[0076] Thereafter, the CPU 131 performs feedback control from Act 2 to Act 9 until it detects a command to end the circulation. When the CPU 131 detects the command to end the circulation, it outputs a command to end the process to the module control unit 38, and the module control unit 38 ends the circulation operation in response to the command from the host control unit 13.

[0077] The liquid ejection device 10 configured as described above can ensure safety and improve printing efficiency. In other words, if a problem occurs in the pressure control in the ink circulation device, the connected liquid ejection head cannot eject and print properly, resulting in poor images, but if the pressure value is within a specified error range, a message box and a buzzer sound, as well as visual and audible warnings, can be used to alert the user. Therefore, by encouraging maintenance, safety can be ensured.

[0078] In addition, a function is provided to notify the user of an abnormality in pressure control and to prompt the user to take measures such as maintenance by displaying a message box and sounding a buzzer. Furthermore, if there is a problem with the pressure control, continuing to print will waste material and the time spent printing, especially with large media; however, by noticing a problem with the pressure control early and stopping continued printing, printing efficiency can be improved.

[0079] Furthermore, the liquid ejection device 10 of the above embodiment judges whether there is a pressure abnormality after a predetermined time has elapsed, thereby suppressing false detections when the pressure is unstable and avoiding the user from frequently changing the target pressure and blocking the stop control. For example, by judging whether there is a pressure abnormality a predetermined time after the start of circulation, or until the pressure reaches the target ±0.01 kPa when the target pressure is changed, or after a predetermined time (e.g., 10 seconds) has elapsed, false detections when the pressure is unstable can be prevented.

[0080] In addition, in the above embodiment, various notification processes can be performed, such as by generating a sound from the buzzer 17 in the circulation device 30 or displaying on the display device 16, so that the user can be notified even if he or she is in a location away from the circulation device 30.

[0081] The configurations of the liquid circulation device and the liquid ejection device of the above-described embodiments are not limited. For example, as the first embodiment, the configuration in which the first tank 34 and the second tank 36 are provided in the first flow path 311 and the second flow path 312 are exemplified, but the present invention is not limited to this. For example, as another embodiment, the liquid ejection device 101 may be configured without the bypass flow path 313 and the bypass tank 35, as in the inkjet recording device 2 shown in FIG. 6. The liquid ejection device 101 is provided with a pressure sensor 44 in the first flow path 311 and a pressure sensor 45 in the second flow path 312, and the CPU 131 calculates the pressure of the nozzle 21 from the detection values ​​of the multiple pressure sensors 44 and 45. For example, the average value of the pressure value of the first flow path 311 detected by the pressure sensor 44 and the pressure value of the second flow path 312 detected by the pressure sensor 45 is calculated as the pressure of the nozzle 21. In such a liquid ejection device 101, the same effect as that of the liquid ejection device 10 according to the first embodiment can be obtained.

[0082] In the first embodiment and other embodiments, the abnormality determination is performed based on the pressure value, but the abnormality determination process is not limited to the above embodiments, and for example, in addition to the abnormality determination based on the pressure value, control for determining the cause of the error may be performed. For example, the CPU 131 determines the cause of the error based on conditions including at least one of the pressure, frequency, pulse width, output value, number of outputs, and temperature.

[0083] For example, when an error occurs in Act 4, the CPU 131 further determines the cause of the malfunction based on the output of the first pump 33, which is a push pump, and the second pump 37, which is a pull pump. For example, based on the minimum value of the pulse width of the first pump 33, which is a push pump, within a certain period of time, the malfunction occurring due to an inability to adjust when the ink in the liquid ejection head 20 runs out and nozzle pulling begins, or an inability to adjust due to ink clogging downstream, is determined as the first error cause. As an example, the CPU 131 determines that the first error cause has occurred when the pulse width of the first pump 33 becomes the minimum value (e.g., 200) five or more times within 100 ms. In this case, which is unlikely to occur in normal operation, if a heater for heating ink is provided, a circulation stop process is immediately performed to prevent dry heating.

[0084] Furthermore, the CPU 131 determines that a malfunction due to upstream ink clogging has occurred as a second error factor, for example, when ink is consumed and the ink bottle becomes empty, based on the output of the pulse width of the second pump 37, which is a pull pump, within a certain period of time. For example, the CPU 131 determines that a second error factor has occurred when the pulse width of the pull pump becomes 400 or less 800 times or more within 1000 ms. Here, with regard to the pulse width, the second error factor assumes upstream ink clogging, but the threshold value takes into consideration that when upstream ink clogging occurs, the second pump 37, which is a pull pump, attempts to match the nozzle surface pressure with a small pulse width.

[0085] In this case, since this phenomenon is similar to that when a large droplet ejection head is used, the circulation process is controlled to wait until a predetermined time (for example, 1000 ms) has elapsed before stopping, so as not to mistake it for large droplet ejection. According to this embodiment, the cause of the error is determined based on the output of the pumps 33 and 37, and the cause can be identified and more appropriate measures can be taken. In addition to the first and second error causes, other causes may be identified, such as when the target pressure is set to an extremely negative pressure and air flows in from the nozzle 21, when ink is clogged somewhere in the circulation path 31, when ink leaks somewhere in the circulation path 31, etc.

[0086] In addition, in each of the above embodiments, an example has been shown in which the second display unit 162 having a message is displayed on the display device 16 provided in the terminal of the host control unit 13, and a sound is generated by the buzzer 17 of the module control unit 38, but the present invention is not limited to this. For example, a notification process may be performed by another external terminal connected by wire or wirelessly. In the above embodiment, the liquid circulation device 30 that circulates the liquid in a circulation path performs the process of stopping the circulation operation and the process of notifying the user as an example of a liquid processing device that flows the liquid in a flow path, but the present invention is not limited to this. For example, in a non-circulation type inkjet head, not limited to a circulation type, the operation of flowing the liquid may be stopped or a notification may be issued when the pressure in the flow path is outside the normal range. In the non-circulation type, the liquid flows from a tank that stores the liquid to the liquid ejection head through a flow path, and the pressure in the flow path is detected by a pressure sensor provided in the flow path.

[0087] For example, the liquid ejected by the liquid ejection device 10 is not limited to ink, and liquids other than ink can also be ejected. An example of a liquid ejection device that ejects liquids other than ink may be a device that ejects liquid containing conductive particles for forming a wiring pattern on a printed wiring board.

[0088] As the second pump 37 and the first pump 33, instead of the piezoelectric pump, for example, a tube pump, a diaphragm pump, a piston pump, or the like may be used.

[0089] Although an example in which multiple ink systems are used has been shown, a configuration including only one liquid ejection device 10 may also be used.

[0090] In addition to the above, the liquid ejection head 20 may have a structure in which ink droplets are ejected by deforming a vibration plate using static electricity, or a structure in which ink droplets are ejected from the nozzles 21 using thermal energy from a heater or the like.

[0091] The configuration of the control system can also be modified as appropriate. For example, in the above embodiment, an example was shown in which a command is output from the host control unit 13 to the module control unit 38 and executed by the module control unit 38, but this is not limited to the above. For example, instead of outputting a command from the host control unit 13 to the module control unit 38, a signal may be output from the module control unit 38 to the host control unit 13, and the host control unit 13 may control the circulation device 30 based on a command from the module control unit 38. For example, the notification process includes driving each unit in the circulation device 30 to display a message or generate a warning sound, as well as outputting a command to perform these processes.

[0092] For example, the control program executed by the host control unit 13 or the module control unit 38 may be provided as a file in an installable or executable format recorded on a recording medium readable by various computers. The control program executed by the host control unit 13 or the module control unit 38 may be configured to be stored in a computer connected to a network such as the Internet and to be provided by downloading it via the network. The program of the embodiment may be configured to be provided or distributed via a network such as the Internet. The control program executed by the host control unit 13 or the module control unit 38 may be configured to be provided by being pre-installed in a ROM or the like. For example, the control method of the above embodiment is performed as an application program of the host control unit 13, and a command is sent to the module control unit 38, but the present invention is not limited to this. For example, the module control unit 38 may be equipped with circuits for circulation control and pump operation stop control, and the above control processing may be performed in the module control unit 38.

[0093] In the above embodiments, the control unit and the control device are provided with a CPU, and the CPU executes a predetermined program to realize the functions of each unit. However, the present invention is not limited to this. For example, LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), GPU ( The above-mentioned processes can be performed using a graphics processing unit (GPS) or other hardware, or the above-mentioned processes can be performed by a combination of software and hardware.

[0094] In addition, in the above embodiment, an example was shown in which the liquid ejection device is used in an inkjet recording device 1, but this is not limited to this, and the liquid ejection device can also be used in, for example, 3D printers, industrial manufacturing machines, and medical applications, enabling miniaturization, weight reduction, and cost reduction.

[0095] Although the embodiment of the present invention has been described, the embodiment is presented as an example and is not intended to limit the scope of the invention. This novel embodiment can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. This embodiment and its modifications are included in the scope and spirit of the invention, and are included in the invention and its equivalents described in the claims. [Explanation of symbols]

[0096] 1...inkjet recording apparatus, 2...inkjet recording apparatus, 10...liquid ejection apparatus, 13...host control unit, 14...power supply, 15...input device, 16...display device, 17...buzzer, 20...liquid ejection head, 21...nozzle, 22...manifold, 30...circulation device, 31...circulation path, 32...cartridge, 33...pump, 34...tank, 35...bypass tank, 36...tank, 37...pump, 38...module control unit, 39...pressure sensor, 41...opening / closing valve, 43...heater device, 44...pressure sensor, 45...pressure sensor, 54...liquid level sensor, 55...liquid level sensor, 70...control board, 71...CPU, 72...memory unit, 73...communication unit, 101...liquid ejection device, 130...computer terminal, 131...CPU, 132...memory unit, 133...communication unit, 151...display box, 161...display unit, 162...display unit, 201...supply port, 202...recovery port, 300...circulation head, 301...case, 311...first flow path, 312...second flow path, 313...bypass flow path, 355...connecting pipe, 751-756...drive circuit, 3131...first bypass flow path, 3132...second bypass flow path.

Claims

1. a flow path through which the liquid flows and which communicates with a liquid ejection head that ejects the liquid; a control unit that stops the operation of flowing the liquid when the pressure in the flow path is outside a normal range.

2. The normal range is set based on a target pressure; The liquid treatment device according to claim 1 , wherein, when the pressure value in the flow path is outside a normal range, the control unit waits until a predetermined time has elapsed or until a predetermined condition is satisfied, and then performs the process of stopping the operation.

3. The liquid treatment device according to claim 1 , wherein the control unit performs a notification process when the pressure is outside the normal range.

4. A control device comprising: a control unit that stops an operation of flowing liquid when a pressure in a flow path through which the liquid flows and that is in communication with a liquid ejection head that ejects the liquid is outside a normal range.

5. A computer used in a liquid processing device having a flow path through which liquid flows and communicates with a liquid ejection head that ejects liquid, A program that realizes a function of stopping the operation of flowing the liquid when the pressure value of the flow path is not within a normal range.

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