Liquid Dispensing System

Abstract

To provide a liquid discharge system that can enhance productivity when cleaning a plurality of heads oriented in different directions.SOLUTION: A liquid discharge system includes: a first nozzle face having a nozzle, from which a liquid is to be discharged; a first head having the first nozzle face; a second nozzle face having a nozzle, from which a liquid is to be discharged, where the second nozzle face is oriented in a direction different from the first nozzle face; a second head having the second nozzle face; a head holder holding the first head and the second head; a first sealer forming a first sealing portion for the first nozzle face; a second sealer forming a second sealing portion for the second nozzle face; a first cleaner configured to clean the first nozzle face in a state where the first sealing portion is formed; and a second cleaner configured to clean the second nozzle face in a state where the second sealing portion is formed.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection system. [Background technology]

[0002] Patent Document 1 discloses a fluid ejection device that includes a fluid ejection head having a nozzle forming surface on which nozzles are formed, a cap member that is in close contact with the nozzle forming surface while leaving a space in the area facing the nozzles, and a cleaning liquid ejection port that is positioned inside the space and ejects cleaning liquid toward the nozzle forming surface, thereby enabling efficient maintenance of the fluid ejection head and cap member. Summary of the Invention [Problem to be solved by the invention]

[0003] In conventional technology, the heads can only be attached in one direction, and it is not possible to clean multiple heads attached in different directions, which reduces productivity during cleaning. [Means for solving the problem]

[0004] The present invention is characterized by comprising a first nozzle surface on which nozzles for ejecting liquid are formed, a first head having the first nozzle surface, a second nozzle surface on which nozzles for ejecting liquid are formed and which is oriented in a direction different from the first nozzle surface, a second head having the second nozzle surface, a head holding member equipped with the first head and the second head, a first contact member that forms a first contact portion with the first nozzle surface, a second contact member that forms a second contact portion with the second nozzle surface, a first cleaning device that cleans the first nozzle surface with the first contact portion formed, and a second cleaning device that cleans the second nozzle surface with the second contact portion formed. [Effects of the Invention]

[0005] According to the present invention, it is possible to provide a liquid ejection system that can improve productivity in cleaning a plurality of heads in different directions. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is an overall schematic view of a liquid ejection system according to an embodiment of the present invention. [Figure 2] FIG. 2 is an overall perspective view showing an example of a head. [Figure 3] FIG. 4 is an explanatory diagram showing an example of a valve mechanism; [Figure 4] FIG. 10 is an explanatory diagram showing the state of nozzle contamination. [Figure 5] FIG. [Figure 6] FIG. 2 is an explanatory diagram showing an example of the configuration of a cleaning station. [Figure 7] FIG. 1 is an overall perspective view showing an example of a head unit. [Figure 8] 10A and 10B are explanatory diagrams showing an example of an operation for forming a contact portion. [Figure 9] FIG. 10 is an explanatory diagram showing a modified example of the configuration of the cleaning station. [Figure 10] FIG. 10 is an explanatory diagram showing a modified example of the configuration of the cleaning station. [Figure 11] FIG. 2 is a block diagram showing an example of a schematic configuration of the hardware of a painting robot. [Figure 12] 10 is a flowchart showing an example of a cleaning operation. [Figure 13] 10 is a flowchart showing an example of a cleaning operation. [Figure 14] 10 is a flowchart showing an example of a paint changing operation. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated explanations will be omitted.

[0008] <Outline of the liquid ejection system> First, an outline of a liquid ejection system will be described with reference to Fig. 1. Fig. 1 is an overall schematic diagram of a liquid ejection system according to an embodiment of the present invention. The liquid ejection system illustrated here is a painting system for painting automobile bodies and the like.

[0009] 1, a painting system 3000 includes a painting robot 1000 and a cleaning station 2000, and the painting system 3000 is installed in a predetermined painting booth 1. The painting robot 1000 is, for example, an articulated robot, and includes a head unit 100 at the tip of the robot arm. The painting robot 1000 can freely move the head unit 100 relative to an object 5000 such as a car body, and can accurately position a head (described later) included in the head unit 100 at a position on the object 5000 where painting is to be performed.

[0010] For example, a painting robot 1000 includes a robot body 10, an articulated arm device 20, and a head unit 100. The robot body 10 is fixed to the floor of a painting booth 1 and supports the articulated arm device 20. The robot body 10 also includes a robot control unit 70 therein, which will be described later.

[0011] The articulated arm device 20 includes a first arm 21a, a second arm 21b, a third arm 21c, a fourth arm 21d, a first joint 22a, a second joint 22b, and a third joint 22c. One end of the first arm 21a is supported by the robot body 10 so as to be rotatable (swivelable) in the direction of the dotted arrow r1, and the other end is connected to one end of the second arm 21b via the first joint 22a. The second arm 21b has one end connected to the first arm 21a via the first joint 22a, and is therefore rotatable in the direction of the dotted arrow r2.

[0012] The other end of second arm 21b is connected to one end of third arm 21c via second joint 22b. One end of third arm 21c is connected to second arm 21b via second joint 22b, and therefore is rotatable in the direction of dotted arrow r3. The other end of third arm 21c is connected to one end of fourth arm 21d via third joint 22c. One end of fourth arm 21d is connected to third arm 21c via third joint 22c, and therefore is rotatable in the direction of dotted arrow r4. The head unit 100 is supported on the other end of fourth arm 21d.

[0013] The rotational movement of each of the arms 21a to 21d is performed by controlling the drive motors provided in each of the joints 22a to 22c by the robot control unit 70. This enables the head unit 100 to move in the vertical direction (up and down) and horizontal direction (left and right) relative to the target object 5000.

[0014] The head placed at the painting position ejects ink, which is an example of a liquid, toward the object 5000 to paint the object 5000. A cleaning station 2000 is installed within the area reachable by the robot arm of the painting robot 1000, and when ink ejection is complete or a predetermined time has elapsed, the painting robot 1000 moves the head unit 100 to the cleaning station 2000. The cleaning station 2000 is equipped with a cleaning device for cleaning the head, and performs a cleaning process on the head provided in the head unit 100.

[0015] <Head configuration> Next, the schematic configuration of the head will be described with reference to Fig. 2. Fig. 2 is an overall perspective view showing an example of the head.

[0016] 2, head 300 is a head that employs an inkjet method. Head 300 mainly comprises nozzle surface 301, nozzles 302, and housing 303. Nozzle surface 301 is provided on one surface of housing 303 and comprises nozzles 302 for ejecting liquid. Nozzles 302 are tiny openings that can be opened and closed by a valve mechanism described below, and when nozzles 302 are in an open state, liquid is ejected from nozzles 302. Housing 303 incorporates a valve mechanism and the like that opens and closes nozzles 302.

[0017] Note that the nozzle surface 301 including the nozzles 302 may be a separate member such as a nozzle plate, and the nozzle plate may be held by the housing 303. Also, the number and arrangement of the nozzles 302 are not limited to the configuration shown in the figure. The number of nozzles 302 may be more than 18, or may be one instead of multiple nozzles. Also, the nozzles 302 may be arranged in a single row instead of multiple rows.

[0018] <Valve mechanism configuration> Next, the configuration of the valve mechanism will be explained using Figure 3. Figure 3 is an explanatory diagram showing the operation of an example of a valve mechanism, with Figure 3(a) showing the state in which the nozzle is closed and Figure 3(b) showing the state in which the nozzle is open.

[0019] The housing 303 of the head 300 shown in Fig. 2 incorporates a valve mechanism 304 as shown in Fig. 3. The valve mechanism 304 is provided so that one valve mechanism 304 is provided for one nozzle 302.

[0020] The valve mechanism 304 includes a valve 305, a liquid supply port 306, and a valve holding member 307. The valve holding member 307 has a space 307a that is hollow in cross section, and includes a liquid supply port 306 near the nozzle 302. The liquid supply port 306 receives liquid that is supplied in an externally pressurized state into the valve holding member 307, and supplies the liquid to the rear portion of the nozzle surface 301. The valve 305 is disposed in the space 307a provided in the valve holding member 307, and is held by the valve holding member 307 via a bearing 308 so as to be axially movable.

[0021] In the above configuration, when the tip of valve 305 is in close contact with nozzle 302 as shown in FIG. 3(a), nozzle 302 is closed, and liquid supplied from liquid supply port 306 is not ejected from nozzle 302. When voltage is applied to valve 305, valve 305 moves in the direction of arrow A as shown in FIG. 3(b), and nozzle 302 opens. This places liquid supply port 306 and nozzle 302 in communication, and liquid is ejected from nozzle 302 as droplets D. Note that valve 305 opens and closes nozzle 302 at high speed at a frequency of several kHz, making it possible to eject liquid drop by drop.

[0022] Here, the dirt on the nozzle part of the head will be explained using Figure 4. Figure 4 is an explanatory diagram showing the state of nozzle dirt.

[0023] When liquid ejection from the nozzle 302 is complete, as shown in Figure 4(a) or 4(b), thickened liquid La may remain on the nozzle 302 and nozzle surface 301. Furthermore, mist generated when liquid is ejected from the nozzle 302 may adhere to the periphery of the nozzle 302 on the nozzle surface 301 as shown in Figure 4(c), and may remain as solidified matter Lb.

[0024] The thickened liquid La and the solidified matter Lb act as resistance when the liquid is ejected from the nozzle 302, causing the liquid to be ejected in a deviated manner (the liquid cannot be ejected correctly to the target position). Furthermore, if the viscosity of the liquid La increases significantly, this may cause ejection failure (the liquid cannot be ejected from the nozzle 302). Therefore, in order to maintain ejection quality, it is necessary to remove the thickened liquid La and the solidified matter Lb.

[0025] <Outline of nozzle cleaning> Next, an overview of nozzle cleaning will be explained using Figure 5. Figure 5 is a schematic explanatory diagram of nozzle cleaning, where Figure 5(a) is a schematic diagram of the head and cleaning device, and Figure 5(b) is an enlarged view of part A in Figure 5(a).

[0026] As described above, the presence of thickened liquid La or solidified matter Lb around the nozzle 302 can cause deflected ejection or ejection failure. Therefore, in this embodiment, the nozzle surface 301 and the nozzle 302 are cleaned by spraying pressurized cleaning liquid Lc onto the nozzle surface 301 using the cleaning nozzle 201. When cleaning the nozzle 302, as shown in FIG. 5(b), the tip of the valve 305 is brought into close contact with the nozzle 302, and the cleaning liquid Lc is sprayed from the cleaning nozzle 201 with the nozzle 302 closed. This makes it possible to wash away foreign matter such as liquid La and solidified matter Lb adhering to the nozzle surface 301 and nozzle 302, thereby maintaining the ejection quality of the head 300.

[0027] <Outline of cleaning station configuration> Next, the schematic configuration of the cleaning station will be described with reference to Fig. 6. Fig. 6 is an explanatory diagram showing an example of the configuration of the cleaning station.

[0028] The cleaning station 2000 is installed in the painting booth 1 as described above, and when the painting robot 1000 moves the head unit 100 to the cleaning station 2000, the cleaning station 2000 cleans the head 300. The cleaning station 2000 includes a cleaning nozzle 201, a tube 202 connected to the cleaning nozzle 201, a nozzle holder 203 that holds the cleaning nozzle 201 at one end, and a main body housing 204 that holds the other end of the nozzle holder 203.

[0029] An opening having an area smaller than the area of ​​the nozzle surface 301 of the head 300 is formed in a part of the main body housing 204, and a contact member 205 is provided around (on the edge of) the opening. When a cleaning process is performed on the head 300, the nozzle surface 301 is pressed against the contact member 205, thereby forming a space (hereinafter referred to as a contact portion) 206 in contact between the head 300 and the cleaning station 2000.

[0030] In the above configuration, when cleaning the head 300, the tip of the valve 305 is brought into close contact with the nozzle 302 to close the nozzle 302, and a contact portion 206 is formed between the head 300 and the cleaning station 2000. In this state, pressurized cleaning liquid Lc is sent to the cleaning nozzle 201 by the tube 202, and the cleaning nozzle 201 sprays the cleaning liquid Lc toward the nozzle surface 301.

[0031] When the cleaning liquid Lc is sprayed onto the nozzle surface 301, if the contact member 205 and the nozzle surface 301 are not in close contact, the cleaning liquid Lc and the like will splash out of the cleaning station 2000 through the gap between the nozzle surface 301 and the contact member 205. The cleaning liquid Lc and the like that splashes out of the cleaning station 2000 will soil the painting booth 1 or fall on the object 5000, leading to deterioration in the quality of the object 5000. Furthermore, if the cleaning liquid Lc splashes on the electrical components of the head 300 or the painting robot 1000, it may cause a malfunction. Therefore, it is necessary to ensure that the nozzle surface 301 and the contact member 205 are in close contact during the cleaning process.

[0032] <Head unit configuration> Next, the schematic configuration of the head unit will be described with reference to Fig. 7. Fig. 7 is an overall perspective view showing an example of a head unit.

[0033] The shapes of objects that can be painted or printed on using inkjet heads are not limited to flat media such as paper, boards, and cloth, but are becoming more diverse, including automobile bodies and building walls, making it necessary to eject liquid onto complex shapes.

[0034] In this embodiment, in order to accommodate liquid ejection onto complex shapes, the head unit 100 is equipped with multiple heads 300A and 300B so that they can be used according to the shape of the target. Head 300A and head 300B are mounted on the head holding member 101 with their respective nozzle surfaces 301A and 301B facing in different directions. In this embodiment, nozzle surface 301A and nozzle surface 301B are installed so that they are offset by 90 degrees.

[0035] The head unit 100 having the above configuration is attached to a painting robot 1000, and the head unit 100 is moved relative to the object 5000 while selectively using the heads 300A and 300B, thereby enabling painting of complex shapes. Note that the number and arrangement of the nozzles 302A and 302B in the heads 300A and 300B are not limited to the configuration shown in the figure. Here, the head 300A is an example of a "first head," and the head 300B is an example of a "second head." The nozzle surface 301A of the head 300A is an example of a "first nozzle surface," and the nozzle surface 301B of the head 300B is an example of a "second nozzle surface."

[0036] <Hardware configuration> Next, the schematic configuration of the hardware of the painting robot according to the embodiment will be described with reference to Fig. 11. Note that components may be added or deleted from the hardware configuration shown in Fig. 11 as needed. Fig. 11 is a block diagram showing an example of the schematic configuration of the hardware of the painting robot 1000.

[0037] The painting robot 1000 has a robot control unit 70 inside the robot body 10. The robot control unit 70 may be provided outside the robot body 10, or may be provided as a device separate from the painting robot 1000.

[0038] The robot control unit 70 includes a CPU (Central Processing Unit) 701, a ROM (Read Only Memory) 702, a RAM (Random Access Memory) 703, and an I / F (Interface) 704.

[0039] The CPU 701 controls the entire painting robot 1000. The CPU 701 is a computing device that implements each function of the painting robot 1000 by reading programs or data stored in the ROM 702 or the storage unit 705, etc., onto the RAM 703 and executing the processing.

[0040] The ROM 702 is a non-volatile memory that can retain programs or data even when the power is turned off. The RAM 703 is a volatile memory used as a work area for the CPU 701. The I / F 704 is an interface for inputting and outputting characters, numbers, various instructions, etc. to and from various external devices. The I / F 704 controls the display of various information such as a cursor, menu, window, characters, or images on a display unit 706 such as an LCD (Liquid Crystal Display). The storage unit 705 stores various data such as programs.

[0041] The display unit 706 displays various types of information such as a cursor, menus, windows, characters, images, etc. The operation panel 707 is a type of input means for inputting characters, numerical values, various instructions, etc., selecting or executing various instructions, selecting a processing target, moving the cursor, etc.

[0042] Furthermore, the robot control unit 70 is connected to the first head 300A, the second head 300B, a cleaning station driving unit 708, and a joint driving motor 709. The first head 300A and the second head 300B perform liquid ejection operations onto the target object 5000 based on commands from the CPU 701. When cleaning the nozzle surface 301A of the head 300A, the cleaning station driving unit 708 performs movement of the head 300A relative to the contact member 205A of the cleaning station 2000 based on commands from the CPU 701. The joint driving motor 709 drives each of the joints 22a to 22c of the articulated arm device 20 of the painting robot 1000 to perform rotational operations of each of the arms 21a to 21d based on commands from the CPU 701.

[0043] However, when the nozzle faces of multiple heads face in different directions, as in head unit 100, the configuration shown in Fig. 6 alone does not allow for simultaneous formation of contact portions 206 on multiple nozzle faces 301A and 301B. Therefore, with the configuration shown in Fig. 6, for example, it is necessary to perform contact and cleaning on head 300A, and then perform contact and cleaning on head 300B, resulting in the problem that the head cleaning process takes a long time. The present invention makes it possible to simultaneously perform cleaning processes on nozzle faces facing different directions, and the details of this are described below.

[0044] <Operation of the embodiment> The operation of forming the contact portion for the two heads provided in the head unit will be described with reference to Fig. 8. Fig. 8 is an explanatory diagram showing an example of the operation of forming the contact portion.

[0045] In this embodiment, a contact area is formed between two heads 300A and 300B, in which nozzle surfaces 301A and 301B face in different directions, making it possible to simultaneously clean nozzle surfaces 301A and 301B, thereby improving the productivity of the cleaning process.

[0046] 8, the head unit 100 is attached to the tip of a robot arm of a painting robot 1000. As shown in FIG. 8(a), a contact member 205A for contacting the nozzle surface 301A of the head 300A is provided in the main body housing 204 of the cleaning station 2000. Furthermore, a power cylinder 207 for moving the contact member 205B back and forth (moving it left and right in the figure) relative to the nozzle surface 301B of the head 300B is provided in the main body housing 204. Note that the state shown in FIG. 8(a) is a state in which the head 300A and the head 300B are not in contact with each other.

[0047] 8(b), the head 300A is moved toward the contact member 205A (in the direction of the arrow a) and the nozzle surface 301A is pressed against the contact member 205A, thereby forming a contact portion 206A between the head 300A and the cleaning station 2000.

[0048] The cleaning nozzle 201A is positioned so that it can spray cleaning liquid onto the nozzle surface 301A when the contact portion 206A is formed. The head 300A is moved toward the contact member 205A by the coating robot 1000. The nozzle surface 301A is pressed against the contact member 205A by the force of the coating robot 1000 holding the head unit 100. In the state shown in FIG. 8(b), the head 300A is in contact and the head 300B is not in contact.

[0049] Once the head 300A is in close contact, the painting robot 1000 ends its operation with the head 300A in close contact and stops there. Next, air is input into the power cylinder 207 in the direction of pushing the cylinder, and as shown in Figure 8(c), the cylinder moves the contact member 205B toward the head 300B (in the direction of arrow b) and presses the contact member 205B against the nozzle surface 301B. This forms a contact area 206B between the head 300B and the cleaning station 2000.

[0050] In this embodiment, the contact portion 206B is formed by tightly contacting the nozzle surface 301B with a cleaning nozzle holding member 208B attached to the cylinder of the power cylinder 207 using a contact member 205B. The cleaning nozzle 201B is disposed within the cleaning nozzle holding member 208B so that cleaning liquid can be sprayed onto the nozzle surface 301B when the contact portion 206B is formed.

[0051] Here, the contact portion 206A is an example of a "first contact portion," and the contact member 205A is an example of a "first contact member." Furthermore, the contact portion 206B is an example of a "second contact portion," and the contact member 205B is an example of a "second contact member." Furthermore, the cleaning nozzle 201A is an example of a "first cleaning device," and the cleaning nozzle 201B is an example of a "second cleaning device." Furthermore, the painting robot 1000 is an example of a "first moving means," and the power cylinder 207 is an example of a "second moving means."

[0052] In this way, the nozzle surface 301A and the contact member 205A are pressed together by driving the coating robot 1000, and the nozzle surface 301B and the contact member 205B are pressed together by driving the power cylinder 207, thereby making it possible to simultaneously form the contact portions 206A and 206B on the nozzle surfaces 301A and 301B facing in different directions. As a result, cleaning liquid can be simultaneously sprayed from the cleaning nozzles 201A and 201B installed in the contact portions 206A and 206B, respectively, making it possible to improve the productivity of the cleaning process.

[0053] Once cleaning of heads 300A and 300B is complete, the contact is released in the reverse order of the procedure used to form the contact area. The power cylinder 207 stops inputting air in the direction of pushing the cylinder out and starts inputting air in the direction of pulling the cylinder in, releasing the contact of head 300B. After the contact of head 300B is released, the painting robot 1000 moves in the direction opposite to the arrow a in Figure 8(b), releasing the contact of head 300A.

[0054] As described above, this embodiment includes a nozzle surface 301A on which nozzles 302A that eject liquid are formed, a head 300A having the nozzle surface 301A, a nozzle surface 301B on which nozzles 302B that eject liquid are formed and which is oriented in a different direction from the nozzle surface 301A, a head 300B having the nozzle surface 301B, a head holding member 101 that includes the head 300A and the head 300B, a contact member 205A that forms a contact portion 206A with the nozzle surface 301A, a contact member 205B that forms a contact portion 206B with the nozzle surface 301B, a cleaning nozzle 201A that cleans the nozzle surface 301A with the contact portion 206A formed, and a cleaning nozzle 201B that cleans the nozzle surface 301B with the contact portion 206B formed.

[0055] This provides a liquid ejection system that can improve productivity in cleaning multiple heads 300A and 300B in different directions. Here, for example, a configuration is conceivable in which two painting robots are provided, one equipped with head 300A on a robot arm and the other equipped with head 300B on a robot arm, are used to paint the target object 5000. However, in this case, the positional accuracy of the target object 5000 deteriorates due to accuracy errors inherent in the painting robots. Furthermore, as the number of painting robots increases, production costs increase, and the payload also increases, which raises the problem of increasing the installation costs of the painting robots. The configuration of this embodiment, in which multiple heads are provided on a single robot arm, is advantageous in addressing these problems.

[0056] As described above, providing separate moving means for creating a contact state for nozzle faces with different orientations can improve the productivity of the cleaning process. In this embodiment, the power cylinder 207 is used as the drive source for the moving means for pressing the nozzle face 301B against the contact member 205B, but the drive source is not limited to this. For example, the contact member 205B may be moved toward the nozzle face 301B by a motor. However, if the ink, paint, or cleaning solution contains a solvent and the coating booth 1 is designated as an explosion-proof area, the use of electrical equipment may violate explosion-proof standards. Therefore, from an explosion-proof perspective, it is considered advantageous to use an air cylinder, which uses air, as the drive source among power cylinders.

[0057] Furthermore, in this embodiment, the painting robot 1000 is used as the driving source for the moving means that presses the nozzle surface 301A against the contact member 205A, but the driving source is not limited to this. To simultaneously clean the nozzle surfaces 301A and 301B, which are facing different directions, each head only needs to be equipped with a separate driving source, and power cylinders may be used for both heads. However, if both driving sources are power cylinders, the cleaning station 2000 must be provided with two power cylinder mounting locations. Therefore, using the painting robot 1000 as one of the driving sources is advantageous in terms of simplifying the configuration of the cleaning station 2000, and it becomes possible to achieve space-saving and cost-effectiveness for the cleaning station 2000.

[0058] As described above, this embodiment includes the painting robot 1000 that moves the nozzle surface 301A and the contact member 205A relatively, and the power cylinder 207 that moves the nozzle surface 301B and the contact member 205B relatively.

[0059] As described above, the painting robot 1000 and the power cylinder 207 have different driving sources.

[0060] As described above, the driving directions of the painting robot 1000 and the power cylinder 207 are different.

[0061] As a result, the cleaning station 2000 can be made smaller in size and at lower cost.

[0062] As described above, at least one of the painting robot 1000 and the power cylinder 207 is connected to an air-driven drive mechanism.

[0063] This makes it possible to accommodate a wide variety of liquids, including liquids containing solvents.

[0064] As shown in FIG. 7 , the head 300A is larger than the head 300B. The larger the nozzle surface area, the greater the force required to bring the head 300A into contact with the contact member 205A. Therefore, in this embodiment, the coating robot 1000 is used as the driving source of the moving means that presses the head 300A, which has a larger nozzle surface area, against the contact member 205A. By using a robot as the driving source for the head that requires a greater force for contact, the driving source of the moving means provided in the cleaning station 2000 only needs to exert a small pressing force. Furthermore, since the driving source of the moving means provided in the cleaning station 2000 can be made smaller, the cleaning station 2000 can be made smaller in size, thereby reducing the space and cost required for the cleaning station 2000.

[0065] As described above, in this embodiment, the painting system 3000 includes a painting robot 1000 that moves the head holding member 101, and at least one of the first moving means that moves the nozzle surface 301A and the adhesion member 205A relatively and the second moving means that moves the nozzle surface 301B and the adhesion member 205B relatively is connected to the painting robot 1000.

[0066] Furthermore, as described above, the nozzle surface 301A has a larger area than the nozzle surface 301B, and the force required to press the contact member 205A against the nozzle surface 301A is greater than the force required to press the contact member 205B against the nozzle surface 301B.

[0067] This allows the painting robot 1000 to press the head that requires a larger force to adhere to the adhesion member (head 300A in this embodiment, which has a larger nozzle surface area) against the adhesion member 205A with a larger force, ensuring reliable adhesion.

[0068] Furthermore, the order in which the two heads 300A and 300B are pressed against the contact members 205A and 205B is such that the head 300A, which has the larger nozzle surface area, is pressed against the contact member 205A first. By contacting the head 300A, which requires a larger force for contact, first, the stability of the two heads 300A and 300B when they are in contact with each other is increased.

[0069] If head 300B, which requires a smaller force for adhesion, is attached first, and then head 300A, which requires a larger force for adhesion, is attached afterwards, head 300B, which was attached first, may be unable to withstand the force that attaches head 300A, causing misalignment. If this misalignment causes heads 300A, 300B and contact members 205A, 205B to lose contact, cleaning liquid may splash around. Therefore, it is desirable to attach heads that require a larger force for adhesion first.

[0070] As described above, in this embodiment, after the close contact portion 206A is formed between the nozzle surface 301A and the contact member 205A, the operation of forming the close contact portion 206B between the nozzle surface 301B and the contact member 205B is started.

[0071] This prevents the contact member from shifting in position relative to the nozzle surfaces during the operation of forming the contact portions, and allows the contact portions to be reliably formed.

[0072] As described above, the head unit 100 of the coating system 3000 includes the head holding member 101 that holds the first nozzle surface 301A of the head 300A and the second nozzle surface 301B of the head 300B. The coating system 3000 also includes a robot arm as a moving means that moves the head holding member 101 of the head unit 100 relative to the first contact member 205A and the second contact member 205B.

[0073] The robot arm integrally moves first nozzle surface 301A of head 300A and second nozzle surface 301B of head 300B, which are held by head holding member 101. The robot arm also has the function of moving head unit 100 relative to object 5000, such as a car body, and accurately positioning head 300A and head 300B provided on head unit 100 at positions on object 5000 where painting will be performed.

[0074] The cleaning station 2000 is provided with a first contact member 205A and a second contact member 205B so that when the head holding member 101 is moved by a robot arm, the first nozzle surface 301A faces the first contact member 205A and the second nozzle surface 301B faces the second contact member 205B.

[0075] This configuration of the robot arm and cleaning station 2000 makes it possible to move two heads facing different directions to positions facing their respective contact members 205A and 205B with a single movement operation of the head holding member 101, without having to move the first nozzle face 301A of head 300A and the second nozzle face 301B of head 300B separately. After the first nozzle face 301A and the second nozzle face 301B are moved to the cleaning station 2000, the first nozzle face 301A and the second nozzle face 301B can be efficiently brought into contact with each other. Furthermore, by providing a first cleaning device that cleans the first nozzle face 301A and a second cleaning device that cleans the second nozzle face 301B, the two nozzle faces can be cleaned simultaneously.

[0076] An example of the flow of the cleaning operation in this embodiment will now be described with reference to Figures 12 to 14. Figure 12 is a flow chart showing an example of the cleaning operation.

[0077] When the cleaning operation for heads 300A and 300B is started, the robot arm moves from the home position for the painting operation to the home position for the cleaning operation (Step S1). When the robot arm reaches the cleaning home position, the robot control unit 70 determines whether the valves 305 of heads 300A and 300B are closed (whether nozzles 302A and 302B are closed) (Step S2). If it is determined in Step S2 that the valves 305 are not closed (No), the valves 305 are closed, and the nozzles 302A and 302B are closed (Step S3).

[0078] Once the valve 305 is closed, the heads 300A, 300B are brought into contact with the contact members 205A, 205B to form contact areas 206A, 206B between the heads 300A, 300B and the cleaning station 2000 (step S4). Once the contact areas 206A, 206B are formed, the cleaning nozzles 201A, 201B installed in the contact areas 206A, 206B eject (spray) cleaning liquid to clean the nozzle surfaces 301A, 301B (step S5).

[0079] In addition to the cleaning nozzles 201A and 201B, air nozzles capable of injecting air may be provided at the contact portions 206A and 206B, and in this case, the air nozzles inject air onto the nozzle surfaces 301A and 301B to which the cleaning liquid has adhered (step S6). Next, the heads 300A and 300B are separated from the contact members 205A and 205B by a predetermined distance, and the contact portions 206A and 206B are released (step S7).

[0080] After the contact portions 206A, 206B are released in step S7, air is again sprayed onto the nozzle surfaces 301A, 301B by the air nozzles (step S8). This second air spray makes it possible to blow away, from the nozzle surfaces 301A, 301B, any foreign matter such as dirt that was pushed into the contact areas between the nozzle surfaces 301A, 301B and the contact members 205A, 205B during the first air spray. After the second air spray is completed, the robot arm moves to the home position, and the cleaning operation is completed (step S9).

[0081] Figure 13 is a flowchart showing another example of a cleaning operation. The flowchart shown in Figure 13 differs from the flowchart shown in Figure 12 in that a paint change operation has been added between steps S1 and S2. Therefore, the same processes or operations as those in the flow shown in Figure 12 are given the same reference numerals, and their explanations will be omitted.

[0082] In the flow shown in Fig. 13, after step S1, the robot control unit 70 determines whether to change the paint used for painting (step S10). If it is determined in step S10 that the paint will not be changed (No), the process proceeds to step S2, and thereafter, the same processing or operation as in the flow shown in Fig. 12 is executed. If it is determined in step S10 that the paint will be changed (Yes), the paint change operation is carried out (step S11).

[0083] The paint changing operation is performed, for example, based on the flow shown in FIG. 14. First, the robot control unit 70 causes the heads 300A and 300B to eject the paint before the change (step S111). Next, it is determined whether the tubes that supply the paint to the heads 300A and 300B should be cleaned (step S112). If it is determined in step S112 that the tubes should not be cleaned (No), the new paint is supplied to the heads 300A and 300B, and the paint changing operation is completed (step S114). If it is determined in step S112 that the tubes should be cleaned (Yes), the tubes are cleaned (step S113), and then step S114 is performed. Once the paint changing operation is completed, the process proceeds to step S2, and thereafter, the same processing or operation as in the flow of FIG. 12 is performed.

[0084] <Modification> Next, a modified example of the cleaning station will be described with reference to Fig. 9. Fig. 9 is an explanatory diagram showing a modified example of the configuration of the cleaning station.

[0085] 6, the contact member 205 is provided on the main body housing 204, whereas in this modified example, the contact member 205 is provided on the main body housing 204 via an elastic member 210.

[0086] To ensure that the nozzle surface 301 is tightly attached, it is necessary to press the nozzle surface 301 parallel to the contact member 205. However, there is a possibility that the nozzle surface 301 may become tilted with respect to the contact member 205 due to a movement error of the painting robot 1000 or the like. Furthermore, as described above, the head 300A is brought into close contact by the driving of the painting robot 1000, but the head 300B is brought into close contact by the driving of the power cylinder 207 attached to the cleaning station 2000. Therefore, an attachment error of the power cylinder 207 is also one of the factors that may cause the nozzle surface 301 to tilt with respect to the contact member 205.

[0087] In order to eliminate such inclination of the contact member 205 with respect to the nozzle surface 301, it is preferable to install the contact member 205 via an elastic member 210 as in this modified example. The contact member 205 is held by a contact member holding member 209, and one end of an elastic member 210 such as a spring is hung on the contact member holding member 209 that holds the contact member 205. The other end of the elastic member 210 is hung on the main body housing 204.

[0088] With the above configuration, even if the nozzle surface 301 is tilted relative to the main body housing 204 as shown in Figure 9(b), the elastic member 210 absorbs the tilt when pressing the nozzle surface 301 against the contact member 205, and the position of the contact member 205 is maintained parallel to the nozzle surface 301, thereby improving contact.

[0089] This modified example can be applied to both cases where the paint robot 1000 is used for contact and where the power cylinder 207 is used for contact, and by providing the contacting member 205 with elasticity, it is possible to improve contact even when the posture of the head 300 is slightly tilted. Note that the other end of the elastic member 210 may be configured to be hooked on a separate member such as a base plate provided separately from the main body housing 204, rather than being hooked directly on the main body housing 204.

[0090] 9 may be configured as an elastic member 310 provided on the head 300 side as shown in Fig. 10. In the modification shown in Fig. 10, in order to eliminate the inclination of the nozzle surface 301 with respect to the contact member 205, a member 309 that abuts against the contact member 205 is installed on the head 300 via the elastic member 310. The contact member 205 is fixed to the main body housing 204.

[0091] With the above configuration, even if the nozzle surface 301 is tilted relative to the main body housing 204 as shown in Figure 10(b), the elastic member 310 absorbs the tilt when pressing the nozzle surface 301 against the contact member 205, and the orientation of the member 309 is maintained parallel to the contact member 205, thereby improving contact.

[0092] As described above, in this embodiment, at least one of the contact members 205A and 205B is supported so that the inclination of the nozzle surface 301 pressed by the contact member can be changed.

[0093] As described above, at least one of the contact members 205A and 205B is supported so as to be able to follow the inclination of the nozzle surface 301 pressed by the contact member.

[0094] As a result, even if the nozzle surface 301 is tilted relative to the main body housing 204, the orientation of the contact member 205 can be maintained parallel to the nozzle surface 301, thereby improving contact.

[0095] Furthermore, in the configuration of this modified example, if the painting robot 1000 or the power cylinder 207 drives at a constant high speed and suddenly stops after pressing the head 300 against the contact member 205, the action of the elastic member 210 may cause vibrations in the contact member 205. When the contact member 205 vibrates, the contact force between the nozzle surface 301 and the contact member 205 weakens, and if a cleaning process is performed in this state, there is a possibility that the cleaning liquid will splash outside the cleaning station 2000. Furthermore, there is a possibility that the contact member 205 will not stop at an appropriate position relative to the nozzle surface 301, making it impossible to properly clean the nozzle surface 301.

[0096] Therefore, the speed of the pressing operation of the painting robot 1000 or the power cylinder 207 may be variably set. For example, by gradually slowing down the speed of the pressing operation of the painting robot 1000 or the power cylinder 207 as the nozzle face 301 approaches the contact member 205, it becomes possible to suppress vibration of the contact member 205 caused by the elastic member 210. By gradually slowing down the speed of the painting robot 1000 or the power cylinder 207 as it approaches the contact member 205, pressing the nozzle face 301 and the contact member 205 together at a speed that does not cause vibration of the elastic member 210 and stopping the head 300, it is possible to reliably bring the nozzle face 301 and the contact member 205 into close contact at an appropriate position.

[0097] As described above, in this embodiment, the speed of the movement operation of the painting robot 1000 and the power cylinder 207 can be variably set.

[0098] As described above, the speed of the movement operation of the painting robot 1000 and the power cylinder 207 slows as the nozzle surface 301A and the nozzle surface 301B approach the contacting member 205A and the contacting member 205B.

[0099] This suppresses vibration of the contact member 205 caused by the elastic member 210, and allows the nozzle surfaces 301A, 301B and the contact members 205A, 205B to be reliably brought into close contact at appropriate positions.

[0100] <Supplementary information> In the present invention, the liquid may be a solution, suspension, emulsion, or the like containing a solvent such as water or an organic solvent, a colorant such as a dye or a pigment, a polymerizable compound, a resin, a surfactant, or the like, a functionalizing material such as DNA, an amino acid, a protein, or calcium, an edible material such as a natural colorant, or the like. The liquid may also contain fine powders such as metal powder. These liquids can be used, for example, as inkjet inks, coating materials, surface treatment solutions, liquids for forming components of electronic devices or light-emitting devices, liquids for forming electronic circuit resist patterns, and liquid materials for 3D modeling.

[0101] The above description is merely an example, and the present invention provides unique effects for each of the following aspects.

[0102] The first aspect includes a first nozzle surface (for example, nozzle surface 301A) on which nozzles for ejecting liquid are formed, a first head (for example, head 300A) having the first nozzle surface, a second nozzle surface (for example, nozzle surface 301B) on which nozzles for ejecting liquid are formed and which is provided facing a direction different from that of the first nozzle surface, a second head (for example, head 300B) having the second nozzle surface, a head holding member (for example, head holding member 101) having the first head and the second head, and a head holding member (for example, head holding member 102) having the first nozzle surface. The nozzle face cleaning device is characterized by comprising a first contact member (e.g., contact member 205A) that forms a first contact portion (e.g., contact portion 206A) on the nozzle face, a second contact member (e.g., contact member 205B) that forms a second contact portion (e.g., contact portion 206B) on the second nozzle face, a first cleaning device (e.g., cleaning nozzle 201A) that cleans the first nozzle face with the first contact portion formed, and a second cleaning device (e.g., cleaning nozzle 201B) that cleans the second nozzle face with the second contact portion formed.

[0103] According to the first aspect, it is possible to provide a liquid ejection system that can improve productivity in cleaning a plurality of heads in different directions.

[0104] The second aspect is characterized in that the first aspect is provided with a first moving means (e.g., a painting robot 1000) that moves the first nozzle surface (e.g., nozzle surface 301A) and the first contact member (e.g., contact member 205A) relatively, and a second moving means (e.g., a power cylinder 207) that moves the second nozzle surface (e.g., nozzle surface 301B) and the second contact member (e.g., contact member 205B) relatively.

[0105] The third aspect is the second aspect, characterized in that the first moving means (for example, the painting robot 1000) and the second moving means (for example, the power cylinder 207) have different driving sources.

[0106] The fourth aspect is characterized in that in the second or third aspect, the driving directions of the first moving means (e.g., painting robot 1000) and the second moving means (e.g., power cylinder 207) are different.

[0107] According to the second to fourth aspects, it is possible to achieve space saving and cost reduction of the cleaning station.

[0108] The fifth aspect is characterized in that, in any of the second to fourth aspects, at least one of the first moving means (e.g., the painting robot 1000) and the second moving means (e.g., the power cylinder 207) is connected to an air-based drive mechanism.

[0109] According to the fifth aspect, it is possible to make it possible to handle a variety of liquids, such as liquids containing solvents.

[0110] A sixth aspect is characterized in that, in any of the second to fifth aspects, the liquid ejection system (e.g., the painting system 3000) includes a robot (e.g., the painting robot 1000) that moves the head holding member (e.g., the head holding member 101), and at least one movement stage of the first movement means and the second movement means is connected to the robot.

[0111] The seventh aspect is characterized in that, in any of the second to sixth aspects, the first nozzle surface (e.g., nozzle surface 301A) has a larger area than the second nozzle surface (e.g., nozzle surface 301B), and the force required to press the first contact member (e.g., contact member 205A) against the first nozzle surface is greater than the force required to press the second contact member (e.g., contact member 205B) against the second nozzle surface.

[0112] According to the sixth and seventh aspects, it is possible to achieve reliable contact with a head that requires a large force when being brought into contact with the contact member.

[0113] The eighth aspect is characterized in that in the seventh aspect, after forming a first contact portion (e.g., contact portion 206A) between the first nozzle surface (e.g., nozzle surface 301A) and the first contact member (e.g., contact member 205A), an operation to form a second contact portion (e.g., contact portion 206B) between the second nozzle surface (e.g., nozzle surface 301B) and the second contact member (e.g., contact member 205B) is started.

[0114] According to the eighth aspect, in the operation for forming the contact portions, the contact member does not become misaligned with respect to the plurality of nozzle faces, and the contact portions can be reliably formed.

[0115] The ninth aspect is characterized in that, in any of the first to eighth aspects, at least one of the first contact member (e.g., contact member 205A) and the second contact member (e.g., contact member 205B) is supported so that its inclination can be changed depending on the inclination of the nozzle surface pressed by the contact member.

[0116] The tenth aspect is characterized in that, in any of the first to eighth aspects, at least one of the first contact member (e.g., contact member 205A) and the second contact member (e.g., contact member 205B) is supported so as to be able to follow the inclination of the nozzle surface pressed by the contact member.

[0117] According to the ninth and tenth aspects, even if the nozzle surface is tilted relative to the main body housing, the orientation of the contact member can be maintained parallel to the nozzle surface, thereby improving contact.

[0118] The eleventh aspect is characterized in that, in any of the second to tenth aspects, the speed of the movement operation by the first movement means (e.g., painting robot 1000) and the second movement stage (e.g., power cylinder 207) can be variably set.

[0119] The 12th aspect is characterized in that, in the 11th aspect, the speed of the movement movement by the first moving stage (e.g., the painting robot 1000) and the second moving stage (e.g., the power cylinder 207) slows down as the first nozzle surface (e.g., the nozzle surface 301A) and the second nozzle surface (e.g., the nozzle surface 301B) approach the first contact member (e.g., the contact member 205A) and the second contact member (e.g., the contact member 205B).

[0120] According to the eleventh and twelfth aspects, vibration of the contact member during the pressing operation is suppressed, and the nozzle surface and the contact member can be reliably brought into contact with each other at an appropriate position. [Explanation of symbols]

[0121] 3000 Painting System 1000 Painting Robots 100 head unit 300 head 301, 301A, 301B nozzle surface 302, 302A, 302B nozzles 2000 Cleaning Station 201, 201A, 201B cleaning nozzle 205, 205A, 205B Adhesion members 206, 206A, 206B Adhesion part 5000 objects [Prior art documents] [Patent documents]

[0122] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-144003

Claims

1. a first nozzle surface in which nozzles for ejecting liquid are formed; a first head having the first nozzle surface; a second nozzle surface, in which nozzles for ejecting liquid are formed and which faces in a direction different from that of the first nozzle surface; a second head having the second nozzle surface; a head holding member including the first head and the second head; a first contact member that forms a first contact portion with the first nozzle surface; a second contact member that forms a second contact portion with the second nozzle surface; a first cleaning device that cleans the first nozzle surface in a state where the first contact portion is formed; a second cleaning device that cleans the second nozzle surface in a state in which the second contact portion is formed; A liquid ejection system comprising:

2. 2. A liquid ejection system according to claim 1, further comprising: a first moving means for moving the first nozzle surface and the first contact member relative to each other; and a second moving means for moving the second nozzle surface and the second contact member relative to each other.

3. 3. The liquid ejection system according to claim 2, wherein the first moving means and the second moving means have different driving sources.

4. 4. The liquid ejection system according to claim 2, wherein the first moving means and the second moving means are driven in different directions.

5. 5. The liquid ejection system according to claim 2, wherein at least one of the first moving means and the second moving means is connected to a driving mechanism that uses air.

6. The liquid ejection system according to any one of claims 2 to 5, characterized in that the liquid ejection system includes a robot that moves the head holding member, and at least one of the first moving means and the second moving means is connected to the robot.

7. A liquid ejection system described in any one of claims 2 to 6, characterized in that the first nozzle surface has a larger area than the second nozzle surface, and the force required to press the first contact member against the first nozzle surface is greater than the force required to press the second contact member against the second nozzle surface.

8. A liquid ejection system according to claim 7, characterized in that after forming a first contact portion between the first nozzle surface and the first contact member, an operation of forming a second contact portion between the second nozzle surface and the second contact member is started.

9. 9. The liquid ejection system according to claim 1, wherein at least one of the first contact member and the second contact member is supported so as to be changeable in accordance with the inclination of the nozzle surface pressed by the contact member.

10. 9. The liquid ejection system according to claim 1, wherein at least one of the first contact member and the second contact member is supported so as to be able to follow the inclination of the nozzle surface pressed by the contact member.

11. 11. The liquid ejection system according to claim 2, wherein the speed of the movement operation by the first movement means and the second movement means can be variably set.

12. 12. A liquid ejection system according to claim 11, wherein the speed of the movement operation by the first moving means and the second moving means slows as the first nozzle face and the second nozzle face approach the first contact member and the second contact member.

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