Coating apparatus and coating system

Abstract

A coating apparatus includes a first head having first nozzles to discharge a liquid from the first nozzles to perform a first coating; a second head having second nozzles to discharge a liquid from the second nozzles to perform a second coating; and a controller configured to determining an order of the first coating and the second coating based on at least one of: a discharge time of each of the first head and the second head; a number of each of the first nozzles and the second nozzles; or a waiting time of one of the first head and the second head when another of the first head and the second head discharges the liquid.

Description

[DESCRIPTION][Title of Invention]COATING APPARATUS AND COATING SYSTEM[Technical Field]

[0001] The present embodiment relates to a coating apparatus and a coating system.[Background Art]

[0002] A coating apparatus that performs coating by discharging a liquid from a head to an object to be coated is known.

[0003] For example, Patent Literature 1 discloses a configuration in which a plurality of heads that discharges liquid in different directions is included, and the discharging heads are selectively used according to the shape of the object.[Summary of Invention][Technical Problem]

[0004] However, in the apparatus of Patent Literature 1, while one head is discharging the liquid to the object, the other heads do not execute the liquid discharge operation. Therefore, when another head performs coating after the coating operation of one head, the cleaning performance of the head may deteriorate due to the progress of drying of the nozzle surface of the one head until the coating by the other head is completed.

[0005] An object of the present embodiment is to suppress deterioration in cleaning performance of a head.[Solution to Problem]

[0006] In an aspect of the present disclosure, a coating apparatus is provided that includes a first head having first nozzles to discharge a liquid from the first nozzles to perform a first coating; a second head having second nozzles to discharge a liquid from the second nozzles to perform a second coating; and a controller configured to determining an order of the first coating and the second coating based on at least one of: a discharge time of each of the first head and the second head; a number of each of the first nozzles and the second nozzles; or a waiting time of one of the first head and the second head when another of the first head and the second head discharges the liquid.[Advantageous Effects of Invention]

[0007] According to the present embodiment, it is possible to suppress deterioration in cleaning performance.[Brief Description of Drawings]

[0008] A more complete appreciation of embodiments of the present disclosure and many of the attendant advantages and features thereof can be readily obtained and understood from the following detailed description with reference to the accompanying drawings.[FIG. 1]FIG. 1 is a diagram illustrating an overall configuration of a coating apparatus according to an embodiment of the present embodiment.[FIG. 2]FIG. 2 is a diagram illustrating a more specific configuration of a liquid supply portion included in the coating apparatus according to an embodiment of the present embodiment. [FIG. 3]FIG. 3 is a cross-sectional view including a plurality of nozzles of a head included in the coating apparatus according to an embodiment of the present embodiment.[FIG. 4A]FIG. 4A is a block diagram illustrating a hardware configuration of the coating apparatus according to an embodiment of the present embodiment.[FIG. 4B]FIG. 4B is a block diagram illustrating a functional configuration of a controller included in the coating apparatus according to an embodiment of the present embodiment.[FIG. 5]FIG. 5 is a view illustrating a first head and a second head included in the coating apparatus according to a first embodiment of the present embodiment.[FIG. 6]FIG. 6 is a view illustrating a configuration example of an object coated by the coating apparatus according to the first embodiment of the present embodiment.[FIG. 7]FIG. 7 is a view illustrating a state of the first head and the second head at the time of maintenance / recovery operation in the coating apparatus according to the first embodiment of the present embodiment.[FIG. 8]FIG. 8 is a view illustrating a state of a maintenance device at the time of the maintenance / recovery operation in the coating apparatus according to the first embodiment of the present embodiment.[FIG. 9 A]FIG. 9A is a block diagram illustrating a functional configuration of a controller included in the coating apparatus according to the first embodiment of the present embodiment.[FIG. 9B]FIG. 9B is a flowchart illustrating an operation of creating a coating route plan by a coating route planning unit included in the coating apparatus according to the first embodiment of the present embodiment.[FIG. 9C]FIG. 9C is a flowchart illustrating an operation of determining a coating order by a coating order determination unit included in the coating apparatus according to the first embodiment of the present embodiment.[FIG. 10]FIG. 10 is a flowchart illustrating a first example of coating and maintenance / recovery operation by the coating apparatus according to the first embodiment of the present embodiment.[FIG. 11]FIG. 11 is a graph illustrating a first example of a relationship between the order of coating by the first head and coating by the second head and the degree of dryness of a liquid adhering to a nozzle surface of each head in the coating apparatus according to the first embodiment of the present embodiment.[FIG. 12]FIG. 12 is a flowchart illustrating a second example of coating and maintenance / recovery operation by the coating apparatus according to the first embodiment of the present embodiment.[FIG. 13]FIG. 13 is a graph illustrating a second example of a relationship between the order of coating by the first head and coating by the second head and the degree of dryness of a liquid adhering to a nozzle surface of each head in the coating apparatus according to the first embodiment of the present embodiment.[FIG. 14]FIG. 14 is a flowchart illustrating a third example of coating and maintenance / recovery operation by the coating apparatus according to the first embodiment of the present embodiment.[FIG. 15 A]FIG. 15A is a first graph illustrating a priority parameter used by the coating apparatus according to the first embodiment of the present embodiment.[FIG. 15B]FIG. 15B is a second graph illustrating a priority parameter used by the coating apparatus according to the first embodiment of the present embodiment.[FIG. 15C]FIG. 15C is a third graph illustrating a priority parameter used by the coating apparatus according to the first embodiment of the present embodiment.[FIG. 15D]FIG. 15D is a fourth diagram illustrating a priority parameter used by the coating apparatus according to the first embodiment of the present embodiment.[FIG. 16]FIG. 16 is a view illustrating a first head and a second head included in a coating apparatus according to a second embodiment of the present embodiment.[FIG. 17A]FIG. 17A is a first diagram illustrating a coating operation by the first head and the second head included in the coating apparatus according to the second embodiment of the present embodiment.[FIG. 17B]FIG. 17B is a second diagram illustrating a coating operation by the first head and the second head included in the coating apparatus according to the second embodiment of the present embodiment.[FIG. 17C]FIG. 17C is a third diagram illustrating a coating operation by the first head and the second head included in the coating apparatus according to the second embodiment of the present embodiment.The accompanying drawings are intended to depict embodiments of the present disclosure and should not be interpreted to limit the scope thereof. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted. Also, identical or similar reference numerals designate identical or similar components throughout the several views. [Description of Embodiments]In describing embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this specification is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that have a similar function, operate in a similar manner, and achieve a similar result.Referring now to the drawings, embodiments of the present disclosure are described below. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0009] A coating apparatus and a coating system according to an embodiment of the present embodiment will be described in detail with reference to the drawings. However, the following embodiments illustrate a coating apparatus and a coating system for embodying the technical idea of the embodiment of the present embodiment, and are not limited to the following.

[0010] The dimensions, materials, shapes, relative arrangements, and the like of the components described in the embodiment of the present embodiment are, unless otherwise specified, notintended to limit the scope of the embodiment of the present embodiment only to such dimensions, materials, shapes, relative arrangements, and the like, and are merely illustrative examples. For example, the size, positional relationship, and the like of the members illustrated in the drawings may be exaggerated for clarity of description. In the following description, like names and like reference signs denote like or equivalent members, and a detailed description thereof may be omitted as appropriate.

[0011] EmbodimentsConfiguration of Coating Apparatus According to Embodiment of Present Embodiment Overall ConfigurationFirst, an overall configuration of a coating apparatus according to an embodiment of the present embodiment will be described with reference to FIG. 1.FIG. 1 is a diagram illustrating an example of an overall configuration of a coating apparatus 100 according to an embodiment of the present embodiment. The coating apparatus 100 applies a liquid to a vehicle body of an automobile that is an object 200 to coat the vehicle body. The object 200 is not limited to the vehicle body of an automobile, but may be a body of an aircraft, a hull of a ship, or other three-dimensional structures.

[0012] The coating apparatus 100 includes four coating robots 2. Each coating robot 2 includes a base portion 10 installed on a floor surface or the like, a first arm 11 provided on the base portion 10, a second arm 12 coupled to the first arm 11, and a head unit 13 provided at a distal end of the second arm 12. The first arm 11 and the second arm 12 of the coating robot 2 are robotic arms rotatably and swingably coupled via joint portions. The first arm 11 and the second arm 12 of the coating robot 2 function as moving mechanisms that are rotationally driven or swingably driven to move the head unit 13 to a desired position. The moving mechanism that moves the head unit 13 may be a linear actuator or the like that linearly moves the head unit 13 in one direction, two directions orthogonal to each other, or three directions, in addition to the robotic arm.

[0013] Specifically, the first arm 11 is provided to be rotatable in a direction of an arrow A in FIG. 1 and to be swingable in a direction of an arrow B with respect to the base portion 10. The second arm 12 is provided to be rotatable in a direction of an arrow C in FIG. 1 and to be swingable in a direction of an arrow D with respect to a distal end of the first arm 11. The head unit 13 is attached to be rotatable in a direction of an arrow E in FIG. 1 and to be swingable in a direction of an arrow F with respect to the distal end of the second arm 12.The number of the coating robots 2 is not limited to four, and may be one, two, three, or five or more.

[0014] The head unit 13 includes a head 1 that discharges liquid, and a position detection portion 3 that detects a position of the object 200. The head 1 includes a plurality of nozzles for discharging liquid. The position detection portion 3 is attached to the distal end of the second arm 12 integrally with the head 1. The position detection portion 3 includes, for example, a stereo camera or the like that detects three-dimensional position information of three or more feature points of the object 200. The stereo camera includes a plurality of cameras. The position detection portion 3 acquires a distance image of the object 200 by a triangulation method based on parallax between images captured by the plurality of cameras.

[0015] The coating apparatus 100 according to the embodiment of the present embodiment includes, in addition to the coating robots 2, a liquid supply portion 4, a maintenance device 40, and a control unit 5.

[0016] The liquid supply portion 4 includes a liquid storage portion 6 and an air supply portion 7. The liquid storage portion 6 is, for example, a tank that stores liquid 8 such as coating material therein. The air supply portion 7 is a compressor or the like that supplies air into the liquid storage portion 6. When air is supplied from the air supply portion 7 to the liquid storage portion 6, the inside of the liquid storage portion 6 is pressurized, so that the liquid 8 in the liquid storage portion 6 is supplied to the head 1 and becomes droplets so as to be discharged from the nozzle of the head 1. The head 1 can also discharge the liquid in the form of threads in addition to droplets. In FIG. 1, only a path for supplying the liquid 8 from the liquid storage portion 6 to one head 1 is illustrated, but the liquid 8 is supplied from the liquid storage portion 6 to all the heads 1 in the same manner. A plurality of liquid storage portions 6 that stores different colors or types of liquid may be prepared, and the color or type of liquid may be switched and supplied to each head 1.

[0017] The maintenance device 40 includes a capping means, a cleaning means, and a wiper blade, which is a wiping member, and the like for maintaining and recovering the function of the head 1. The maintenance device 40 is provided for each of the coating robots 2. In a case where the next coating is not performed for a while after coating, or in a case where the coating is performed by switching the coating liquid to a different color or type, the maintenance device 40 performs the maintenance / recovery operation after the end of the previous coating. Specifically, the nozzle surface of the head 1 is capped, and the residual liquid adhering to the head 1 is washed away by the cleaning liquid. As a result, clogging of the nozzle due to drying of the residual liquid can be prevented, and adhesion of the residual liquid to the object when the coating liquid is switched and applied can be prevented.

[0018] The control unit 5 controls the operation of each coating robot 2 and the discharge operation of each head 1 based on the position information of the object 200 detected by the positiondetection portion 3 in addition to shape data of the object 200, coating data, and the like input in advance. As a result, the head unit 13 is moved along the shape of the object 200, and the coating liquid is applied from the head 1 to the surface of the object 200. The control unit 5 also controls the operation of the maintenance device 40. In FIG. 1, only signal lines from the control unit 5 to one coating robot 2, one head 1, and one maintenance device 40 and a signal line from one position detection portion 3 to the control unit 5 are illustrated, but the control unit 5 controls the operations of all the coating robots 2, all the heads 1, and all the maintenance devices 40, and receives sensing signals from all the position detection portions 3. Examples of the coating data include coating information (color information) corresponding to image data and shape data of the coated state.

[0019] Liquid Supply Portion 4FIG. 2 is a diagram illustrating a more specific configuration of the liquid supply portion 4 included in the coating apparatus 100 according to the embodiment of the present embodiment.

[0020] The liquid supply portion 4 includes a plurality of air regulators 9 in addition to the liquid storage portion 6 and the air supply portion 7. The air regulator 9 is provided in an air flow path 111 connecting the air supply portion 7 and the plurality of liquid storage portions 6. The air regulator 9 adjusts the air pressure sent from the air supply portion 7 to each liquid storage portion 6. The plurality of liquid storage portions 6 is individually connected to each head 1 included in each coating robot 2 via an air flow path 112. Therefore, when the inside of each liquid storage portion 6 is pressurized, the liquid 8 is supplied from each liquid storage portion 6 to each head 1. The liquid storage portion 6 may not be provided for each head 1, but may be one liquid storage portion provided in common for all the heads 1.

[0021] Head 1FIG. 3 is a cross-sectional view including a plurality of nozzles 24 of the head 1 included in the coating apparatus 100 according to an embodiment of the present embodiment.

[0022] A plurality of discharge modules 23 is arranged in a row or a plurality of rows in a housing 20. Each discharge module 23 includes a nozzle plate 25, a nozzle valve 26, a piezoelectric element 27, and a liquid flow path 28. The nozzle plate 25 is provided with the nozzle 24 for discharging liquid for each discharge module 23. The nozzle 24 is openable and closable by the nozzle valve 26. The piezoelectric element 27 is a driving means that expands and contracts when a voltage is applied to open and close the nozzle valve 26. The liquid flow paths 28 communicate with each other between the discharge modules 23 to form a common flow path. The liquid flow paths 28 also communicate with a supply port 21 and a collection port 22.

[0023] In a state where the valve of the collection port 22 is closed, when the liquid is supplied from the supply port 21 into the housing 20, the liquid flows into the liquid flow path 28 and is pressurized. At this time, when no voltage is applied to the piezoelectric element 27, since the nozzle 24 is closed by the nozzle valve 26, no liquid is discharged from the nozzle 24. Even when the nozzle 24 is closed, the liquid can flow through the liquid flow path 28. On the other hand, when a voltage is applied to the piezoelectric element 27, the nozzle valve 26 is driven, and the nozzle 24 is opened, so that the liquid is discharged from the nozzle 24. The liquid that has not been discharged from the nozzle 24 is discharged to the outside through the collection port 22.

[0024] Hardware ConfigurationFIG. 4A is a block diagram illustrating an example of a hardware configuration of the coating apparatus 100 according to the embodiment of the present embodiment.

[0025] As illustrated in FIG. 4A, the coating apparatus 100 includes an input device 700A, a computer 300, a controller 400, a head control device 500, and a robot control device 600 in addition to the plurality of coating robots 2. Here, only two coating robots 2 are illustrated, and the remaining coating robots 2 are omitted.

[0026] Each of the coating robots 2 includes an encoder sensor 16 and a robot drive portion 17. The encoder sensor 16 is an optical sensor or the like that optically detects a slit of an encoder provided in a coupling portion between the base portion 10 and the first arm 11, a coupling portion between the first arm 11 and the second arm 12, and a coupling portion between the second arm 12 and the head unit 13 of the coating robot 2. Since the rotation amount and the swing amount of each of the first arm 11, the second arm 12, and the head unit 13 can be grasped by the detection of the encoder sensor 16, three-dimensional position information of the head unit 13 can be acquired. The robot drive portion 17 is a drive portion that performs a rotation operation and a swing operation of the first arm 11, the second arm 12, and the head unit 13.

[0027] The input device 700A is a device to which information regarding shape data of the object 200, image data of coating, coordinate data, a coating mode, a coating range (coating start position, coating end position), a coating instruction, and the like is input. The input device 700A includes a keyboard, a mouse, a touch panel, and the like for a user or the like to perform an input operation. Various pieces of information input in the input device 700A are sent to the computer 300.

[0028] The computer 300 includes a raster image processor (RIP) unit 301 that performs image processing on image data received from the input device 700A, and a rendering unit 302 that decomposes the image data into coating data for each scan of the head unit 13. The computer 300 receives the shape data of the object 200 from the input device 700A, acquires the actual position information of the object 200 detected by the position detection portion 3, and generates a coating route of the coating robot 2 based on the shape data and the actual position information of the object 200. The computer 300 calculates an incident angle a of the droplet with respect to the object 200 in the generated coating route. The incident angle a is calculated by using any one of shape data of the object 200 received from the input device 700A, position information of the object 200 detected by the position detection portion 3, and three-dimensional position information of the head unit 13 detected by the encoder sensor 16, or these pieces of information.

[0029] The controller 400, the head control device 500, and the robot control device 600 function as the control unit 5 illustrated in FIG. 1 that controls the operation of each coating robot 2 and the discharge operation of each head 1. In this case, one head control device 500 and one robot control device 600 are provided, but the head control device 500 and the robot control device 600 may be individually provided for each coating robot 2.

[0030] The controller 400 receives coating data and an instruction signal from the computer 300 and controls the entire operation of the coating apparatus 100.

[0031] The controller 400 includes a central processing unit (CPU) 401, read only memory (ROM) 402, random access memory (RAM) 403, a hard disk drive / solid state drive (HDD / SSD) 404, and an VF 405.These are communicably connected to each other via a system bus S.

[0032] The CPU 401 executes control processing including various types of arithmetic processing. The ROM 402 stores a program used for driving the CPU 401, such as an initial program loader (IPL). The RAM 403 is used as a work area of the CPU 401. The HDD / SSD 404 stores various types of information such as programs, captured images acquired by the stereo camera, detection information by various sensors such as the encoder sensor 16, and the like. The I / F 405 is an interface for connecting the controller 400 to various external devices. Here, the external devices are the head control device 500, the robot control device 600, and the like. At least a part of the function implemented by the CPU 401 may be implemented by an electric circuit or an electronic circuit.

[0033] The head control device 500 receives a control signal and a discharge cycle signal from the controller 400, and controls the discharge amount and the discharge timing of the head 1based on the received control signal and discharge cycle signal. At this time, by controlling the discharge amount and the discharge timing of the head 1 based on the incident angle a, the amount of droplets to be discharged and a landing interval Px in a moving direction X are controlled to the amount of droplets and the landing interval according to the incident angle a.

[0034] The robot control device 600 receives a control signal from the controller 400, and controls driving of the robot drive portion 17 based on the received synchronization control signal.At this time, the robot drive portion 17 is controlled based on the incident angle a, whereby an inclination P of the nozzle row of the head 1 is controlled, and a landing interval Py in a movement orthogonal direction Y is controlled to a landing interval according to the incident angle a.

[0035] Functional Configuration of Controller in Embodiment of Present EmbodimentFIG. 4B is a block diagram illustrating an example of a functional configuration of the controller 400 included in the coating apparatus 100 according to an embodiment of the present embodiment. FIG. 4A will also be described with appropriate reference.

[0036] The controller 400 includes a system control unit 411, a nozzle valve drive control unit 412, a discharge cycle signal generation unit 413, a memory control unit 414, a data storage unit 415, a robot control signal generation unit 416, and a maintenance / recovery control unit 418.

[0037] Each function of the system control unit 411, the nozzle valve drive control unit 412, the discharge cycle signal generation unit 413, the memory control unit 414, the robot control signal generation unit 416, and the maintenance / recovery control unit 418 is implemented by the CPU 401 executing processing defined in a program stored in a nonvolatile memory such as the ROM 402. The function of the data storage unit 415 is implemented by a nonvolatile memory such as the HDD / SSD 404. The system control unit 411 receives coating data and an instruction signal from the computer 300 and controls the entire operation of the coating apparatus 100. The system control unit 411 may include the functions of the RIP unit 301 and the rendering unit 302 included in the computer 300.

[0038] The nozzle valve drive control unit 412 generates a control signal for controlling the opening / closing drive of the nozzle valve 26 based on the coating data and the incident angle a received from the computer 300. The discharge cycle signal generation unit 413 generates a discharge cycle signal of the head 1 based on an output signal from the encoder sensor 16, and coating data and the incident angle a received from the computer 300. The memory control unit 414 controls the data storage unit 415. The data storage unit 415 stores coating data, coating range data, and the like received from the computer 300. The robot control signal generation unit 416 generates a synchronization control signal for matching the drive ofeach coating robot 2 with a droplet discharge operation on the basis of the coating data and the information of the coating route from the computer 300. The robot control signal generation unit 416 generates a control signal for determining the inclination P of the nozzle row of the head 1 on the basis of the incident angle a calculated by the computer 300. The maintenance / recovery 0 418 controls the operation of the maintenance device 40.

[0039] First EmbodimentConfiguration of Coating Apparatus According to First Embodiment of Present Embodiment First Head 1A and Second Head IBFIG. 5 is a view illustrating an example of a configuration of a first head 1 A and a second head IB included in the coating apparatus 100 according to the first embodiment of the present embodiment. FIG. 6 is a view illustrating an example of a configuration of the object 200 coated by the coating apparatus 100 according to the first embodiment of the present embodiment. In the example illustrated in FIG. 5, for the purpose of indicating that each of the first head 1A and the second head IB includes the head 1 illustrated in FIG. 3, the reference sign of the head 1 is written in parentheses after the reference sign of the first head 1A, and the reference sign of the head 1 is written in parentheses after the reference sign of the second head IB. Hereinafter, reference signs may also be written in parentheses for the same purpose.

[0040] The coating apparatus 100 according to the first embodiment of the present embodiment includes the first head 1A and the second head IB. Each of the first head 1A and the second head IB includes at least one nozzle 24, and discharges liquid from the nozzle 24 to perform coating.

[0041] Here, for example, in a coating apparatus that performs coating by discharging liquid from each of two heads, while one head is discharging the liquid to an object, the other head may not discharge liquid. In a coating apparatus that does not clean the two heads until the discharge from each of the two heads is completed, as the liquid is dried in the head that does not discharge the liquid, the viscosity of the liquid increases, and the component contained in the liquid solidifies, so that the cleaning performance of the head may be deteriorated. For example, in a state where the liquid is not being dried, the liquid adhering to the nozzle can be easily removed by wiping the vicinity of the nozzle with a wiping member, so that the head can be suitably cleaned. On the other hand, in a state where the liquid is dried, the component contained in the liquid adheres to the nozzle, so that the liquid adhering in the vicinity of the nozzle cannot be removed even when the vicinity of the nozzle is wiped, or the time required for the removal increases, so that the cleaning performance of the head is deteriorated.

[0042] In a case where the cleaning of the two heads is not performed until the discharge from each of the two heads is completed, in the head that comes first in the order of coating, the waiting time until the cleaning of the head is performed becomes long, and the liquid is dried, so that the cleaning performance tends to be deteriorated. In a case where a head having a long discharge time among the two heads performs discharge later, cleaning of the head is not performed until the discharge of the head having a long discharge time is completed in the head that has performed discharge earlier and has a short discharge time, so that the liquid is dried and the cleaning performance tends to be deteriorated. Among the two heads, the head having a large number of nozzles has a relatively higher probability that the component of the liquid adheres to the nozzle due to drying than a head having a small number of nozzles (when the number of nozzles is large, the amount of liquid remaining near the nozzle increases, and as a result, the possibility of adhering to the nozzle increases), and thus the cleaning performance of the head tends to be deteriorated.

[0043] The coating apparatus 100 according to the present embodiment determines the order of coating by the first head 1A and coating by the second head IB based on at least one of the liquid discharge time, the number of nozzles 24, and the waiting time of the other head when one head is discharging of each of the first head 1A and the second head IB. For example, when the discharge time of the first head 1A is longer than the discharge time of the second head IB, the coating apparatus 100 determines the order of coating such that coating by the first head 1A is performed before coating by the second head IB. As a result, in the first head 1A, the length of the waiting time until the head is cleaned is substantially the same as the discharge time of the second head IB, and thus the waiting time until the head is cleaned can be shortened as compared with the case where the second head IB performs coating first. By shortening the waiting time until the cleaning of the head is performed, the progress of the drying of the liquid can be suppressed, and the deterioration of the cleaning performance of the head can be suppressed. When the number of nozzles of the first head 1A is smaller than the number of nozzles of the second head IB, the coating apparatus 100 according to the present embodiment determines the order of coating so that the coating by the first head 1A is performed before the coating by the second head IB. As a result, in the second head IB in which the probability that the component of the liquid adheres to the nozzle due to drying is high, the waiting time until the cleaning of the head is performed is shortened, so that the progress of the drying of the liquid can be suppressed, and the deterioration of the cleaning performance of the head can be suppressed. In the present embodiment, since the cleaning is performed at one time after the discharge from all the heads is completed, the cleaning time of the head is shortened as compared with the coating apparatus that sequentially cleans the heads at the timing when the discharge from each of the two heads is completed, and as a result, the productivity of the coating apparatus 100 can be improved.

[0044] There are the following determination methods for determining the order of coating. Here, the method is described for the coating apparatus 100 including two heads (the first head 1A and the second head IB).(1) The order of coating is determined from the liquid discharge time by the first head 1A (including the non-discharge time between the first drop and the next drop) and the liquid discharge time by the second head IB (including the non-discharge time between the first drop and the next drop).In addition to the determination based on the “discharge time” in (1) above, the order of coating may be determined based on the “waiting time”. Specifically,(2) the order of coating may be determined by using the time when the second head is not discharging the liquid as the liquid discharge time by the first head 1A (including the non- discharge time between the first drop and the next drop), that is, by using the “waiting time” of the second head IB, or by using the time when the first head 1A is not discharging the liquid as the liquid discharge time by the second head IB (including the non-discharge time between the first drop and the next drop), that is, by using the “waiting time” of the first head 1A.

[0045] Discharge TimeThe “discharge time” in the first embodiment of the present embodiment will be described. The “discharge time of one droplet” includes the discharge time of the first droplet from a certain nozzle and the non-discharge time to the next droplet. For example, when 1000 droplets are continuously discharged, the “discharge time” is obtained by multiplying the time obtained by adding the discharge time of the first droplet and the non-discharge time to the next droplet by 1000. Even when the liquid has a thread-like shape, when coating is performed in which discharge is continuously performed without switching between the first head 1A and the second head IB, the non-discharge time, which is a time between the threadlike shape and the thread-like shape, is also included in the discharge time.

[0046] A certain period of time when droplets are continuously or intermittently discharged from a head having a plurality of nozzles is defined as a “liquid discharge time” from the head. That is, the liquid discharge time from the first head 1A refers to a time including the non- discharge time between the nozzle droplet and the next droplet from the nozzle of the first head 1A. Similarly, the liquid discharge time from the second head IB refers to a time including the non-discharge time between a droplet from the nozzle and the next droplet from the second head IB.

[0047] At this time, while the first head 1A is performing coating (liquid discharge), the second head IB is not performing coating. Therefore, the “liquid discharge time” of the first head 1 A corresponds to the “time during which no liquid is discharged”, that is, the “waiting time” ofthe second head IB. Therefore, for example, in determining the order of coating in the first embodiment of the present embodiment, the “waiting time of the liquid of the second head IB” may be used instead of the “liquid discharge time of the first head 1 A”. The “discharge time” may be compared with the “waiting time”. For example, the order of coating may be determined by the “liquid discharge time by the first head 1 A” and the “waiting time of the first head 1A”.

[0048] In a head having a plurality of nozzles, when only some of the nozzles are used for coating and most of the other nozzles (however, nozzles that have performed coating at least once) are not used for coating, and the degree of dryness in the vicinity of the nozzles increases during that time, the time may be regarded as the “waiting time”.

[0049] When the head switching time increases, the total time of the coating process increases. Therefore, the number of times of switching of the head in the “total coating time” (= discharge time of the first head 1A (waiting time of the second head IB) + waiting time of the first head 1A (discharge time of the second head IB) + switching time of the head for coating (when the first head 1A is used as a reference)) is preferably small. Therefore, it is preferable to consider reducing the number of times of switching when determining the order of coating. The discharge time is not limited to a future discharge time in a case where the discharge time is planned before the start of coating. For example, when the plan is corrected after the start of coating, the time required for coating may be included. When the plan is corrected after the start of coating, the order of coating may be determined in consideration of the usage status (for example, the coating start time, the waiting time from the first discharge to the next discharge for checking the head operation, and the like) of the head so far.

[0050] Coating TimeThe “total coating time” in the first embodiment of the present embodiment will be described. For example, when a first coating region is coated by the first head 1A and a second coating region is coated by the second head IB, the “total coating time” of the first and second coating regions is “coating time of the first coating region” + “coating time of the second coating region” + “head switching time”. Regarding the “coating time”, for example, the waiting time of the second head IB when the first coating region is coated by the first head 1 A corresponds to the ““non-coating time” of the second head IB”. Similarly, the waiting time of the first head 1A when the second coating region is coated by the second head IB corresponds to the ““non-coating time” of the first head 1 A”.

[0051] The second head IB includes the plurality of heads 1 illustrated in FIG. 3. In the example illustrated in FIG. 5, the second head IB includes 12 heads 1 arranged in a directionorthogonal to the direction in which the nozzles 24 are arranged. The second head IB is supported by the second arm 12 of the coating robot 2. The first head 1A is supported by the second head IB via a supporting member 30 of a single head 1 illustrated in FIG. 3.

[0052] The first head 1A includes a first nozzle surface 15A provided with nozzles. The second head IB includes a second nozzle surface 15B provided with nozzles. The first head 1A and the second head IB are arranged such that the first nozzle surface 15A and the second nozzle surface 15B face different directions from each other in a state where the first head 1A and the second head IB are attached to the second arm 12. In the example illustrated in FIG. 5, the first nozzle surface 15A and the second nozzle surface 15B face directions orthogonal to each other. By arranging the first nozzle surface 15A and the second nozzle surface 15B so as to face different directions from each other, in a case where the object 200 includes a plurality of surfaces intersecting each other, it is possible to coat the plurality of surfaces by reducing the inclination angle of the first head 1A and the second head IB as compared with a case where the first head 1A and the second head IB face the same direction. However, the directions of the first nozzle surface 15A and the second nozzle surface 15B are not limited to the directions orthogonal to each other, and may be intersecting directions other than the orthogonal directions such as the case of being inclined.

[0053] In the coating apparatus 100, since the first head 1A is supported by the supporting member 30, coating can be favorably performed on the object 200 having a complicated structure such as a vehicle body. For example, as illustrated in FIG. 6, a first region 201 can be coated by the second head IB, and a second region 202 having a narrower coating region than the first region 201 can be coated by the first head 1A. That is, since the first head 1A is provided so as to protrude from the distal end of the second arm 12 via the supporting member 30 having a plate shape, the first head 1A can enter a narrow place even when the object 200 has a complicated structure. At the same time, it is possible to cause the first head 1A to approach the object 200 while avoiding interference with the object 200. As a result, it is possible to perform coating well even in a portion of the object 200 where it is difficult to perform coating.

[0054] In the coating apparatus 100, the directions of the first nozzle surface 15A and the second nozzle surface 15B intersect with each other. Therefore, the coating apparatus 100 performs the operation of covering each of the first nozzle surface 15A and the second nozzle surface 15B with caps by the maintenance device 40 at different timings in a state where the second arm 12 of the coating robot 2 is stationary.

[0055] Maintenance device 40A configuration of the maintenance device 40 included in the coating apparatus 100 according to the first embodiment of the present embodiment will be described with reference to FIGS.7 and 8. FIG. 7 is a view illustrating an example of a state of the first head 1A and the second head IB at the time of maintenance / recovery operation in the coating apparatus 100 according to the first embodiment of the present embodiment. FIG. 8 is a diagram illustrating an example of a state of the maintenance device 40 at the time of the maintenance / recovery operation in the coating apparatus 100 according to the first embodiment of the present embodiment.

[0056] The maintenance device 40 includes a cap 41 that covers the nozzles 24 included in the first head 1A and the second head IB. The maintenance device 40 includes a first maintenance device 40A used for the maintenance / recovery operation of the first head 1A and a second maintenance device 40B used for the maintenance / recovery operation of the second head IB larger than the first head 1A. The configuration of the first maintenance device 40A and the configuration of the second maintenance device 40B may be substantially the same.Therefore, in the description of FIG. 8, the first maintenance device 40A will be described as a representative.

[0057] The first maintenance device 40A illustrated in FIG. 8 includes a cleaning portion 42 and a drying portion 43 in addition to the cap 41. The cap 41 includes a cap body 50 formed in a concave shape and a seal portion 51 provided over the entire edge of an opening 50a of the cap body 50. The seal portion 51 is formed of an elastic body such as rubber. In the cap body 50, the cleaning portion 42 and the drying portion 43 are arranged. The cleaning portion 42 includes a cleaning nozzle 52 for discharging a cleaning liquid. The drying portion 43 includes a drying nozzle 53 that blows dry air such as hot air. The dry air is not limited to hot air, but may be cold air. A waste liquid flow path 54 for discharging the cleaning liquid from the inside of the cap body 50 to a waste liquid tank is provided at the bottom of the cap body 50.

[0058] When maintaining / recovering the discharge function of the first head 1A and the second head IB by the maintenance device 40, first, the coating apparatus 100 drives the coating robot 2 to move the second head IB to a position facing the cap 41 of the second maintenance device 40B. Thereafter, the coating apparatus 100 presses the second nozzle surface 15B of the second head IB against and makes contact with the cap 41 as illustrated in FIG. 7. As a result, the second nozzle surface 15B of the second head IB is covered with the cap 41 of the second maintenance device 40B. The cap 41 of the second maintenance device 40B is pressed against the second head IB, and the seal portion 51 (see FIG. 8) of the cap 41 is brought into close contact with the second nozzle surface 15B. As a result, the secondnozzle surface 15B and the cap 41 are sealed. At this time, the first head 1A is arranged at a position facing the cap 41 of the first maintenance device 40A.

[0059] As illustrated in FIG. 8, the coating apparatus 100 moves the cap 41 of the first maintenance device 40A in a Z direction, and presses and contacts the cap 41 against and with the first nozzle surface 15A of the first head 1A. The coating apparatus 100 presses the cap 41 of the first maintenance device 40A against the first head 1 A. As a result, the seal portion 51 of the cap 41 of the first maintenance device 40A comes into close contact with the first nozzle surface 15 A, and the space between the first nozzle surface 15A and the cap 41 of the first maintenance device 40A is sealed. In this state, the coating apparatus 100 can perform the maintenance / recovery operation using the maintenance device 40, that is, clean the first nozzle surface 15A and the second nozzle surface 15B using the cleaning portion 42 and the drying portion 43.

[0060] Functional Configuration of Controller in First Embodiment of Present Embodiment A functional configuration of the controller 400 included in the coating apparatus 100 according to the first embodiment of the present embodiment will be described with reference to FIGS. 9A, 9B, and 9C. FIG. 9A is a block diagram illustrating an example of a functional configuration of the controller 400 included in the coating apparatus 100 according to the first embodiment of the present embodiment.

[0061] The controller 400 illustrated in FIG. 9A is mainly different from the controller 400 illustrated in FIG. 4A in including a coating route planning unit 419 and a coating order determination unit 420. The control unit 5 including the controller 400 illustrated in FIG. 9A corresponds to a control unit that controls liquid discharge by the first head 1A and the second head IB.

[0062] Each function of the coating route planning unit 419 and the coating order determination unit 420 is implemented by the CPU 401 executing processing defined in a program stored in a nonvolatile memory such as the ROM 402. Each function of the coating route planning unit 419 and the coating order determination unit 420 may be implemented by an external device other than the controller 400 such as the computer 300 or may be implemented by distribution processing between the controller 400 and an external device other than the controller 400 such as the computer 300 with the functional configuration of the controller 400 as illustrated in FIG. 4B, for example.

[0063] For example, the coating route planning unit 419 plans a coating route at the start of coating (step SOI). The coating route refers to a path for relatively moving the first head 1A and the second head IB with respect to the object 200 in order to coat the entire coating region of the object 200. The coating route planning unit 419 plans a coating route based on a coatingregion determined from the shape of the coating region in the object 200 and the shapes of the first head 1A and the second head IB that coat the coating region or the arrangement of the nozzles 24. The coating route planning unit 419 plans which of the first region 201 or the second region 202 illustrated in FIG. 6 is coated first and which of the first head 1A or the second head IB is used.

[0064] Regarding creation of the plan of the coating route in FIG. 9B, in a case where information of the coating route is acquired from the computer 300, it can be omitted by using the information. The timing of planning the coating route is not limited to the start of coating. This may be a time point of maintenance / recovery control (capping or the like), a time point when any head performs discharge, or the like.

[0065] FIG. 9B is a flowchart illustrating an example of processing of creating a coating route plan by the coating route planning unit 419 included in the coating apparatus 100 according to the first embodiment of the present embodiment. As an example, the coating route planning unit 419 starts the operation of FIG. 9B at the timing of start of coating (new coating instruction after previous maintenance / recovery operation).

[0066] First, in step Si l, the coating route planning unit 419 acquires coating object shape data.

[0067] Subsequently, in step S12, the coating route planning unit 419 acquires coating region data.

[0068] Subsequently, in step S13, the coating route planning unit 419 acquires head information (head shape data).

[0069] Subsequently, in step S14, the coating route planning unit 419 acquires nozzle arrangement data.

[0070] Subsequently, in step S15, the coating route planning unit 419 creates a coating route plan.

[0071] Subsequently, in step S16, the coating route planning unit 419 acquires or estimates information regarding the coating time from the planned coating route.

[0072] The coating route planning unit 419 provides the planned coating route to a head drive program when it is not a trigger for changing the coating order at the start of coating. When it is set (or instructed) to determine the coating order, the coating order is subsequently determined.

[0073] The order of steps S 11 to S 14 may be changed as appropriate, and each step may be executed in parallel.

[0074] The coating order determination unit 420 determines the order of coating by the first head 1A and coating by the second head IB based on at least one of the liquid discharge time and the number of nozzles 24 of each of the first head 1A and the second head IB.

[0075] FIG. 9C is a flowchart illustrating an example of the coating order determination processing by the coating order determination unit 420 included in the coating apparatus 100 according to the first embodiment of the present embodiment. As an example of the timing at which the coating order determination unit 420 determines the coating order, the first head 1A and the second head IB are in a clean state, that is, at the start of the coating process, or immediately after the first head 1A and the second head IB are cleaned. However, it is not limited to “immediately after”. Planning may be performed during cleaning or it may be during stop of the operation after cleaning. The plan may be revised. For example, in a case where some event occurs, for example, the degree of dryness changes, in a case where one of the plurality of robots is interrupted due to a defect and repair coating is performed, or in a case where repair coating is performed by sensing a coating defect, the plan correction may be performed.

[0076] First, in step S21, the coating order determination unit 420 determines the liquid discharge time by each of the first head 1A and the second head IB in each coating region based on the size of the coating region and the position of the coating region in the coating route planned by the coating route planning unit 419.

[0077] Subsequently, in step S22, the coating order determination unit 420 determines whether or not coating by the first head 1A and coating by the second head IB is sufficient based on the basis of the liquid discharge time. Specifically, when it is determined that the degree of dryness in the vicinity of the nozzles of the first head 1A and the second head IB is equal to or less than a threshold after the lapse of the “coating time” estimated in step S16 (after completion of coating) in a predetermined coating order (for example, coating in the order of the first head 1A and the second head IB) in the planned coating route (step S22, YES), the coating order determination unit 420 ends the processing without changing the coating order. On the other hand, when it is determined in step S22 that the degree of dryness exceeds the threshold (that is, the cleaning performance of the nozzle is deteriorated) (step S22, NO), the order is changed.

[0078] Subsequently, in step S23, the coating order determination unit 420 determines whether or not the discharge time of the first head 1A and the second head IB are the same. When it isdetermined in step S23 that the discharge times are the same (step S23, YES), in step S24, the coating order determination unit 420 changes the order so that one of the first head 1A and the second head IB having the smaller number of nozzles comes first. Thereafter, the coating order determination unit 420 ends the processing. On the other hand, when it is determined in step S23 that the discharge times are not the same (step S23, NO), the coating order determination unit 420 performs the order change so that the coating with the head having the longer discharge time is performed first in step S25.

[0079] Subsequently, in step S26, the coating order determination unit 420 determines whether or not the drying in the vicinity of the nozzle of each head is equal to or less than a threshold, that is, whether or not the liquid is dried. When it is determined in step S26 that the liquid is not dried (step S26, YES), the coating order determination unit 420 determines the coating order at that time, and then ends the processing. When it is determined that the liquid is dried (step S26, NO), the coating order determination unit 420 adds 1 to the number of times of switching of the head in step S27. For example, if the order of coating is perform coating with the second head IB first and then perform coating with the first head 1A, the number of times of head switching is “1”. On the other hand, the number of times of head switching is increased, and a part of the coating process by the second head IB is performed after the coating process by the first head 1A. That is, coating is performed in the order of the second head IB, the first head 1A, and the second head IB. In this case, the number of times of head switching is “2”. As the number of times of head switching increases, the coating time slightly increases, but the order is determined with priority given to suppressing drying of the nozzle. The coating order determination unit 420 can sort by setting the head switching timing to a predetermined condition, for example, setting 1 / 4 of the discharge time to the latter half. Thereafter, the coating order determination unit 420 performs the processing of step S22 and subsequent steps again.

[0080] As described above, the coating order is determined such that the nozzle dryness at the time of completion of coating is equal to or less than the threshold. This makes it possible to suppress deterioration in cleaning performance of the head.

[0081] The order of S23 to S27 in this flowchart is not limited to the order illustrated in FIG. 9C. For example, it is also possible to calculate priority parameters from the “number of nozzles” and the “discharge time” of each head and determine the coating order by comparing the parameters.

[0082] Operation of Coating Apparatus According to First Embodiment of Present Embodiment First ExampleA first example of the operation of the coating apparatus according to the first embodiment of the present embodiment will be described with reference to FIGS. 10 and 11. FIG. 10 is a flowchart illustrating a first example of the maintenance / recovery operation by the coating apparatus 100. FIG. 11 is a diagram illustrating a first example of the relationship between the order of coating by the first head 1A and coating by the second head IB and the degree of dryness of the liquid adhering to the nozzle surface of each head in the coating apparatus 100 according to the first embodiment of the present embodiment. FIG. 11 illustrates an example of a temporal change in the degree of dryness of the liquid on the first nozzle surface 15A on the upper side, and an example of a temporal change in the degree of dryness of the liquid on the second nozzle surface 15B on the lower side.

[0083] For example, the coating apparatus 100 starts the operation of FIG. 10 on condition that the start operation of the maintenance / recovery operation is received via an operation portion included in the coating apparatus 100. However, the start condition of the operation of FIG. 10 is not limited to the reception of the start operation, and can be appropriately set. In the operation illustrated in FIG. 10, the liquid discharge time by the second head IB is longer than the liquid discharge time by the first head 1A. It is assumed that the coating route is planned in advance by the coating route planning unit 419 and the coating order is determined in advance by the coating order determination unit 420.

[0084] First, in step S31, the coating apparatus 100 drives the second arm 12 by the coating robot 2 according to the coating order determined by the coating order determination unit 420, and moves the second head IB to a position facing the first region 201 of the object 200 illustrated in FIG. 6, that is, a coating start position by the second head IB.

[0085] Subsequently, in step S32, the coating apparatus 100 opens the nozzle valve 26 of the second head IB and discharges liquid from the second head IB to coat the first region 201 of the object 200. The coating apparatus 100 performs coating until a coating time T1 illustrated in FIG. 11 elapses.

[0086] Subsequently, in step S33, when the coating by the second head IB is completed, the coating apparatus 100 drives the second arm 12 by the coating robot 2 according to the coating order determined by the coating order determination unit 420. The coating apparatus 100 moves the first head 1A to a position facing the second region 202 of the object 200, that is, a coating start position by the first head 1A by driving the second arm 12.

[0087] Subsequently, in step S34, the coating apparatus 100 opens the nozzle valve 26 of the first head 1A and discharges the liquid from the first head 1A to coat the second region 202 of theobject 200. The coating apparatus 100 performs coating until a coating time T2 illustrated in FIG. 11 elapses.

[0088] Subsequently, in step S35, when the coating by the first head 1 A is completed, the coating apparatus 100 drives the second arm 12 by the coating robot 2, and covers the first nozzle surface 15A and the second nozzle surface 15B with the cap 41. As a result, it is possible to reduce drying of the liquid on each of the first nozzle surface 15A and the second nozzle surface 15B, and it is possible to suppress deterioration in cleaning performance of each of the first nozzle surface 15A and the second nozzle surface 15B. The coating apparatus 100 performs the operation of step S35 in a period T3 illustrated in FIG. 11.

[0089] Subsequently, in step S36, the coating apparatus 100 executes the maintenance / recovery operation of cleaning each of the first nozzle surface 15A and the second nozzle surface 15B using the cleaning portion 42 and the drying portion 43 by the maintenance device 40. The coating apparatus 100 performs the operation of step S36 in a period T4 illustrated in FIG. 11.

[0090] As described above, the coating apparatus 100 can coat the first region 201 and the second region 202 of the object 200.

[0091] In the first example, coating by the second head IB having a long coating time T1 is executed first (S32), and then coating by the first head 1A is executed at the coating time T2 shorter than the coating time T1 (S34). As a result, it is possible to suppress deterioration in cleaning performance of the head due to the progress of drying of the liquid adhering to the second nozzle surface 15B of the second head IB that has discharged the liquid earlier during the execution of the coating by the first head 1A. Since the degree of dryness of the liquid until cleaning can be suppressed, the cleaning time can be shortened as a result.

[0092] In the first example, after the coating by the first head 1A and the second head IB is executed, the first nozzle surface 15A and the second nozzle surface 15B are covered with the cap 41 (S35). As a result, productivity can be improved as compared with the case of performing the operation of covering the first nozzle surface 15A with the cap 41 after execution of coating by the first head 1A, and then covering the second nozzle surface 15B with the cap 41 after execution of coating by the second head IB.

[0093] The heads used in the first example are not limited to the first head 1A and the second head IB illustrated in FIG. 5. For example, the number of heads 1 included in the first head 1A and the number of heads 1 included in the second head IB may be the same, or the number of nozzles 24 included in the first head 1A and the number of nozzles 24 included in the second head IB may be the same. After the execution of step S16 in FIG. 10, coating may befurther performed. At this time, the same operation as in steps S31 to S34 may be executed, or coating may be performed with only one of the first head 1A and the second head IB.

[0094] Second ExampleA second example of the operation of the coating apparatus according to the first embodiment of the present embodiment will be described with reference to FIGS. 12 and 13. FIG. 12 is a flowchart illustrating a second example of the maintenance / recovery operation by the coating apparatus 100. FIG. 13 is a diagram illustrating a second example of the relationship between the order of coating by the first head 1A and coating by the second head IB and the degree of dryness of the liquid adhering to the nozzle surface of each head in the coating apparatus 100 according to the first embodiment of the present embodiment. FIG. 13 illustrates an example of a temporal change in the degree of dryness of the liquid on the first nozzle surface 15A on the upper side, and an example of a temporal change in the degree of dryness of the liquid on the second nozzle surface 15B on the lower side.

[0095] Drying of the first nozzle surface 15A and the second nozzle surface 15B after discharge progresses, and when the first nozzle surface 15A and the second nozzle surface 15B perform discharge again without being cleaned, discharge failure is likely to occur. For this reason, in the coating using the first head 1A and the second head IB, it is desirable to continuously perform the coating at one time and avoid the intermittent coating operation from the viewpoint of coating quality. However, the coating apparatus 100 can also perform a plurality of discontinuous coatings depending on the request of the coating route and the quality conditions. When performing a plurality of discontinuous coatings, the coating apparatus 100 determines the order of coating by the first head 1A and coating by the second head IB based on the discharge time of each of the first head 1A and the second head IB. For example, the order of coating by the first head 1A and coating by the second head IB is determined so that coating with longer discharge time is performed first, and then coating is performed by alternately using the first head 1A and the second head IB. In other words, when the discharge time of the first head 1A is longer than the discharge time of the second head IB, the first head 1A performs coating prior to the second head IB, and the second head IB performs coating after completion of coating by the first head 1A. The first head 1A performs coating again after the second head IB performs coating. By these operations, even when a plurality of discontinuous coatings is performed in accordance with the request of the coating route and the quality conditions, the occurrence of discharge failure can be reduced and the coating quality can be improved. Details of the above operation will be described below.

[0096] For example, the coating apparatus 100 starts the operation of FIG. 12 on condition that the start operation of the maintenance / recovery operation is received via the operation portionincluded in the coating apparatus 100. In the operation illustrated in FIG. 12, the liquid discharge time by the first head 1A is longer than the liquid discharge time by the second head IB. Hereinafter, differences from the operation illustrated in FIG. 10 will be mainly described.

[0097] In step S42, the coating apparatus 100 opens the nozzle valve 26 of the second head IB and discharges the liquid from the second head IB to coat the first region 201 of the object 200. The coating apparatus 100 performs coating until a coating time Tl-1 illustrated in FIG. 13 elapses.

[0098] Subsequently, in step S45, the coating apparatus 100 drives the second arm 12 by the coating robot 2, and moves the second head IB to a position facing the first region 201 of the object 200 illustrated in FIG. 6, that is, a coating start position by the second head IB.

[0099] Subsequently, in step S46, the coating apparatus 100 opens the nozzle valve 26 of the second head IB and discharges the liquid from the second head IB to coat the first region 201 of the object 200. The coating apparatus 100 performs coating until a coating time Tl-2 illustrated in FIG. 13 elapses.

[0100] As described above, the coating apparatus 100 can coat the first region 201 and the second region 202 of the object 200 in a case where a plurality of discontinuous coatings is performed according to the request of the coating route and the quality condition.

[0101] Also in the second example, the same effects as those of the first example can be obtained. The heads used in the second example are not limited to the first head 1A and the second head IB illustrated in FIG. 5. For example, the number of heads 1 included in the first head 1A and the number of heads 1 included in the second head IB may be the same, or the number of nozzles 24 included in the first head 1A and the number of nozzles 24 included in the second head IB may be the same. Further, after the execution of step S48 in FIG. 12, coating may be further performed. At this time, the same operation as in steps S41 to S47 may be executed, or coating may be performed with only one of the first head 1A and the second head IB.

[0102] Third ExampleA third example of the operation of the coating apparatus according to the first embodiment of the present embodiment will be described with reference to FIG. 14. FIG. 14 is a flowchart illustrating a third example of maintenance / recovery operation by the coating apparatus 100 according to the first embodiment of the present embodiment.

[0103] When a head having a larger number of nozzles 24 is used in coating, there is a higher possibility that liquid adheres to the first nozzle surface 15A and the second nozzle surface 15B due to a defect such as non-discharge of liquid from the nozzles 24. When the liquid adheres to the first nozzle surface 15A and the second nozzle surface 15B, cleaning performance is likely to be deteriorated due to drying of the adhering liquid. In the third example, when discharge is performed first from a head with a smaller number of nozzles 24, it is possible to reduce adhesion of the liquid to the first nozzle surface 15A and the second nozzle surface 15B, and to suppress deterioration in cleaning performance of the first head 1A and the second head IB.

[0104] For example, the coating apparatus 100 starts the operation of FIG. 14 on condition that the start operation of the maintenance / recovery operation is received via the operation portion included in the coating apparatus 100. The number of nozzles N1 of the first head 1A is smaller than the number of nozzles N2 of the second head IB. Hereinafter, differences from the operation illustrated in FIG. 10 will be mainly described.

[0105] First, in step S51, the coating apparatus 100 drives the second arm 12 by the coating robot 2 according to the coating order determined by the coating order determination unit 420, and moves the first head 1A to a position facing the second region 202 of the object 200 illustrated in FIG. 6, that is, a coating start position by the first head 1A.

[0106] Subsequently, in step S52, the coating apparatus 100 opens the nozzle valve 26 of the first head 1A and discharges the liquid from the first head 1A to coat the second region 202 of the object 200.

[0107] Subsequently, in step S53, when the coating by the first head 1 A is completed, the coating apparatus 100 drives the second arm 12 by the coating robot 2 according to the coating order determined by the coating order determination unit 420. The coating apparatus 100 moves the second head IB to a position facing the first region 201 of the object 200, that is, a coating start position by the second head IB by driving the second arm 12.

[0108] Subsequently, in step S54, the coating apparatus 100 opens the nozzle valve 26 of the second head IB and discharges the liquid from the second head IB to coat the first region 201 of the object 200.

[0109] As described above, the coating apparatus 100 can coat the first region 201 and the second region 202 of the object 200. By the operation of the third example, it is possible to suppress deterioration of the cleaning performance of the second nozzle surface 15B of the second head IB having a larger number of nozzles N2. In the third example, the waiting time of thefirst head 1A having a smaller number of nozzles N1 is preferably as short as possible, for example, a time during which the degree of dryness of the first head does not increase. Therefore, as long as the degree of dryness of the first head 1A does not increase, the liquid discharge times by the second head IB and the first head 1A may be the same, and the liquid discharge time by the second head IB may be longer than the liquid discharge time by the first head 1A.

[0110] Fourth ExampleA fourth example of the operation of the coating apparatus according to the first embodiment of the present embodiment will be described with reference to FIGS. 15 A to 15D. FIG. 15A is a first graph illustrating a priority parameter used by the coating apparatus according to the first embodiment of the present embodiment. FIG. 15B is a second graph illustrating a priority parameter used by the coating apparatus according to the first embodiment of the present embodiment. FIG. 15C is a third graph illustrating a priority parameter used by the coating apparatus according to the first embodiment of the present embodiment. FIG. 15D is a fourth diagram illustrating a priority parameter used by the coating apparatus according to the first embodiment of the present embodiment.

[0111] The fourth example is different from the first to third examples in that the order of coating by the first head 1A and coating by the second head IB is determined based on both the liquid discharge time and the number of nozzles of each of the first head 1A and the second head IB.

[0112] Specifically, the liquid discharge time is denoted by T, the number of nozzles is denoted by N, the number of nozzles of a certain head n among a plurality of heads including the first head 1A and the second head IB is denoted by Nn, and the discharge time is denoted by Tn. The symbol n is a natural number of 2 or more. The coating apparatus 100 calculates a priority parameter Tn / Nn based on the discharge time Tn and the number of nozzles Nn.

[0113] FIGS. 15 A to 15D illustrate a map of the priority parameter Tn / Nn with the vertical axis representing the discharge time T and the horizontal axis representing the number of nozzles N. The longer the discharge time T and the smaller the number of nozzles N, the higher the priority. Information regarding the priority parameter Tn / Nn such as the map illustrated in FIGS. 15A to 15D is stored in a nonvolatile memory such as the HDD / SSD 404 illustrated in FIG. 4A. The coating order determination unit 420 of the coating apparatus 100 refers to the map stored in the nonvolatile memory and determines the order of coating by the first head 1A and coating by the second head IB so that the head having a larger value of the priority parameter Tn / Nn performs coating first.

[0114] In FIG. 15B, a point 1A-1 indicates the priority parameter Tn / Nn of the first head 1A, and a point IB-1 indicates the priority parameter Tn / Nn of the second head IB. In the example illustrated in FIG. 15B, the liquid discharge time T by the first head 1A is longer than the liquid discharge time by the second head IB, and the number of nozzles N of the first head 1A is smaller than the number of nozzles N of the second head IB. Since the priority parameter Tn / Nn of the first head 1A is higher than Tn / Nn of the second head IB, the coating order determination unit 420 determines the coating order so that coating by the first head 1A is performed first and coating by the second head IB is performed after coating by the first head 1A. The coating apparatus 100 can perform coating according to the flowchart illustrated in FIG. 10.

[0115] FIG. 15C illustrates a case where the liquid discharge time T by the first head 1A and the liquid discharge time T by the second head IB are the same, and the priority parameter Tn / Nn of the first head 1A is larger than the priority parameter Tn / Nn of the second head IB. A point 1A-2 represents the priority parameter Tn / Nn of the first head 1A, and a point IB-2 represents the priority parameter Tn / Nn of the second head IB. Since the priority parameter Tn / Nn of the first head 1A is higher than Tn / Nn of the second head IB, the coating order determination unit 420 determines the coating order so that coating by the first head 1A is performed first and coating by the second head IB is performed after coating by the first head 1A. The coating apparatus 100 can perform coating according to the flowchart illustrated in FIG. 10.

[0116] FIG. 15D illustrates a case where the number of nozzles N of the first head 1A is the same as the number of nozzles N of the second head IB. A point 1A-3 represents the priority parameter Tn / Nn of the first head 1A, and a point IB-3 represents the priority parameter Tn / Nn of the second head IB. Since the priority parameter Tn / Nn of the first head 1A is higher than Tn / Nn of the second head IB, the coating order determination unit 420 determines the coating order so that coating by the first head 1A is performed first and coating by the second head IB is performed after coating by the first head 1A. The coating apparatus 100 can perform coating according to the flowchart illustrated in FIG. 10.

[0117] The coating apparatus 100 can obtain the same effect as that of the first example by performing the operation of the fourth example.

[0118] Second EmbodimentNext, a coating apparatus according to a second embodiment will be described. The same names and reference signs as those of the embodiment described above indicate the same or similar members or configurations, and detailed description thereof will be omitted as appropriate.

[0119] FIG. 16 is a view illustrating an example of the first head 1A and the second head IB included in the coating apparatus according to the second embodiment of the present embodiment. The second embodiment of the present embodiment is different from the first embodiment of the present embodiment in that the first nozzle surface 15 A of the first head 1A and the second nozzle surface 15B of the second head IB face the same direction.

[0120] The coating operation by the first head and the second head included in the coating apparatus according to the second embodiment of the present embodiment will be described with reference to FIGS. 17A to 17C. FIG. 17A is a first diagram illustrating a coating operation by the first head and the second head included in the coating apparatus according to the second embodiment of the present embodiment. FIG. 17B is a second diagram illustrating a coating operation by the first head and the second head included in the coating apparatus according to the second embodiment of the present embodiment. FIG. 17C is a third diagram illustrating a coating operation by the first head and the second head included in the coating apparatus according to the second embodiment of the present embodiment.

[0121] It is assumed that the first head 1A and the second head IB illustrated in FIGS. 17A to 17C discharge liquids of different colors. In FIGS. 17A to 17C, a moving direction 211 represents a direction in which the first head 1A and the second head IB are moved. A width direction 212 represents a direction intersecting the moving direction 211.

[0122] First, as illustrated in FIG. 17A, the coating apparatus 100 discharges the liquid of the first color from the second head IB while moving the first head 1A and the second head IB in the moving direction 211, and coats the object 200 with the first color.

[0123] Subsequently, as illustrated in FIG. 17B, the coating apparatus 100 discharges the liquid of the second color different from the first color from the first head 1A while moving the first head 1A and the second head IB in the moving direction 211, and coats the object 200 with the second color. In the example illustrated in FIG. 17B, the first head 1A and the second head IB are moved in the moving direction 211 in a state of being inclined with respect to the moving direction 211 in order to perform coating in the second color with a width narrower than the width applied in FIG. 17 A in the width direction 212.

[0124] Subsequently, as illustrated in FIG. 17C, the coating apparatus 100 discharges the liquid of the first color from the second head IB while moving the first head 1A and the second head IB in the moving direction 211, and coats the object 200 with the first color.

[0125] In the example illustrated in FIGS. 17A to 17C, two-tone color coating is possible. Also in the second embodiment of the present embodiment, the coating apparatus 100 determines the order of coating by the first head 1A and coating by the second head IB based on at least one of the liquid discharge time and the number of nozzles of each of the first head 1A and the second head IB. As a result, the same effects as those of the coating apparatus according to the first embodiment of the present embodiment can be obtained. The colors of the liquids discharged from the first head 1A and the second head IB are not limited to two colors, but may be three or more colors. The number of types may be two or more. For example, the colors may be the same, but properties such as the degree of dryness may be different. The coating apparatus 100 is not limited to the first head 1A and the second head IB, and may include three or more heads.

[0126] Although the preferred embodiments have been described in detail above, it is not limited to the embodiments of the above-described present embodiment, and various modifications and substitutions can be made to the embodiments of the above-described embodiment without departing from the scope described in the claims.

[0127] An embodiment of the present embodiment includes a coating system. For example, the coating system according to the embodiment of the present embodiment includes the coating apparatus 100 according to the first embodiment of the present embodiment, and the maintenance device 40 including the cap 41 that covers the nozzles 24 included in the first head 1A and the second head IB. The maintenance device 40 covers the nozzles 24 included in each of the first head 1A and the second head IB with the cap 41 after the second head IB performs coating. With this configuration, it is possible to reduce drying of the liquid on each of the first nozzle surface 15A and the second nozzle surface 15B, and it is possible to suppress deterioration in cleaning performance of each of the first nozzle surface 15A and the second nozzle surface 15B. In the coating system, since the coating system includes the maintenance device 40, the coating apparatus 100 does not necessarily include the maintenance device 40.

[0128] The present embodiment is also applicable to coating performed for purposes other than coloring and designing on a vehicle body of an automobile, for example. For example, a coating process for a vehicle body of an automobile includes undercoating aiming to secure adhesion of a coating film on and rust prevention for a base material of a vehicle body, intermediate coating aiming to secure impact resistance and durability, and top coating aiming to coloring and designing, for example. The coating apparatus according to the present embodiment may be used for undercoating or intermediate coating, in addition to top coating. When there is, after the top coating, a coating process for applying a protective layer such as a clear layer aiming to lustering and protection of the coating film, the coating device accordingto the present embodiment may be used in the coating process for applying the protective layer. When a peelable protective layer for protecting the coating surface is coated on an automobile that is shipped or that is in a factory, it is also possible to use the coating apparatus according to the present embodiment for coating the protective layer. The peelable protective layer may be any layer as long as it adheres to a coating surface of a vehicle body to make it possible to chemically or physically protect a coating portion from dust, metal powder, oil, salt, acid, and ultraviolet rays, and is preferably formed to include a material mainly containing an acrylic copolymer agent, for example.

[0129] The present embodiment is also applicable to a droplet discharge device that discharges droplets for purposes other than coating. For example, there is a marking device that discharges droplets to an object to mark a specific portion.A coating apparatus includes: a first head having first nozzles to discharge a liquid from the first nozzles to perform a first coating; a second head having second nozzles to discharge a liquid from the second nozzles to perform a second coating; and a controller configured to determining an order of the first coating and the second coating based on at least one of: a discharge time of each of the first head and the second head; a number of each of the first nozzles and the second nozzles; or a waiting time of one of the first head and the second head when another of the first head and the second head discharges the liquid.The controller controls the first head to perform the first coating before controlling the second head to perform the second coating, and the controller controls the second head to perform the second coating after controlling the first head to complete the first coating, when the discharge time of the first head is longer than the discharge time of the second head; or when the waiting time of the second head is longer than the waiting time of the second head.The controller controls the first head to perform the first coating again after controlling the second head to perform the second coating.The controller controls the first head to perform the first coating before controlling the second head to perform the second coating when the number of the first nozzles is smaller than the number of the second nozzles.The controller configured to control the first head and the second head to respectively discharge the liquid from the first nozzles and the second nozzles. The controller determines the order of the first coating and the second coating based on at least one of: the discharge time; the number of each of the first nozzles and the second nozzles; or the waiting time of one of the first head and the second head when another of the first head and the second head discharges the liquid.The controller determines the discharge time based on a coating time of the first head and the second head, and the controller determines the waiting time based on non-coating time of each of the first head and the second head.The controller determines the order of the first coating and the second coating to control a dryness of the first nozzles and the second nozzles to be equal to or less than a threshold. The first head includes the first nozzles arrayed in a first direction on a first nozzle surface, the second head includes the second nozzles, arrayed in a second direction different from the first direction, on a second nozzle surface.The coating apparatus according includes: a maintenance device including a cap to cover the first nozzles in the first head and the second nozzles in the second head, wherein the maintenance device covers the first nozzles in the first head and the second nozzles in the second head with the cap after the first head completes the first coating and the second head completes the second coating.A coating system includes: the coating apparatus; and a maintenance device including a cap covering the first nozzles in the first head and the second nozzles in the second head, wherein the controller controls the maintenance device to cover the first nozzles in the first head and the second nozzles in the second head with the caps after controlling the first head to complete the first coating and controlling the second head to complete the second coating. The functionality of the elements disclosed herein may be implemented using circuitry or processing circuitry which includes general purpose processors, special purpose processors, integrated circuits, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), and / or combinations thereof which are configured or programmed, using one or more programs stored in one or more memories, to perform the disclosed functionality. Processors are considered processing circuitry or circuitry as they include transistors and other circuitry therein. In the disclosure, the circuitry, units, or means are hardware that carry out or are programmed to perform the recited functionality. The hardware may be any hardware disclosed herein which is programmed or configured to carry out the recited functionality.

[0130] Aspects of the present embodiment are, for example, as follows.Aspect 1According to Aspect 1, a coating apparatus includes: a first head and a second head, each of the first head and the second head including at least one nozzle, the first head and the second head discharging liquid from the nozzle to perform coating, wherein an order of coating by the first head and coating by the second head is determined based on at least one of a liquid discharge time, a number of nozzles, and a waiting time of one head when the other head performs discharge of each of the first head and the second head.Aspect 2According to Aspect 2, in the coating apparatus of Aspect 1, the first head performs coating prior to the second head when the discharge time of the first head or the waiting time of the second head is longer than the discharge time of the second head or the waiting time of the first head, and the second head performs coating after completion of coating by the first head.Aspect 3According to Aspect 3, in the coating apparatus of Aspect 2, the first head performs coating again after the second head performs coating.Aspect 4According to Aspect 4, in the coating apparatus of any one of Aspects 1 to 3, the first head performs coating before the second head in a case where the number of the nozzles of the first head is smaller than the number of the nozzles of the second head.Aspect 5According to Aspect 5, the coating apparatus of any one of Aspects 1 to 4, includes: a control unit configured to control discharge of liquid by each of the first head and the second head, wherein the control unit determines an order of coating by the first head and coating by the second head based on at least one of the discharge time, the number of nozzles, and the waiting time of one head when the other head performs discharge of each of the first head and the second head.Aspect 6According to Aspect 6, in the coating apparatus of any one of Aspects 1 to 5, the discharge time refers to a coating time of each of the first head and the second head, and the waiting time refers to a non-coating time of each of the first head and the second head.Aspect 7According to Aspect 7, in the coating apparatus of Aspect 5, the control unit determines a coating order such that a nozzle dryness is equal to or less than a threshold.Aspect 8According to Aspect 8, in the coating apparatus of any one of Aspects 1 to 7, the first head includes a first nozzle surface on which the nozzle is provided, the second head includes a second nozzle surface on which the nozzle is provided, and the first head and the second head are arranged such that the first nozzle surface and the second nozzle surface face different directions.Aspect 9According to Aspect 9, the coating apparatus of any one of Aspects 1 to 8, includes: a maintenance device configured to include a cap covering the nozzles included in the first head and the second head, wherein the maintenance device covers the nozzles included in each of the first head and the second head with the cap after completion of coating by the first head and the second head.Aspect 10,According to Aspect 10, a coating system includes: the coating apparatus according to any one of Aspects 1 to 8; and a maintenance device configured to include a cap covering the nozzles included in the first head and the second head, wherein the maintenance device covers the nozzles included in each of the first head and the second head with the cap after completion of coating by the first head and the second head.The above-described embodiments are illustrative and do not limit the present invention. Thus, numerous additional modifications and variations are possible in light of the above teachings. For example, elements and / or features of different illustrative embodiments may be combined with each other and / or substituted for each other within the scope of the present invention. Any one of the above-described operations may be performed in various other ways, for example, in an order different from the one described above.This patent application is based on and claims priority to Japanese Patent Application No. 2024-021888, filed on February 16, 2024, in the Japan Patent Office, the entire disclosure of which is hereby incorporated by reference herein.[Reference Signs List]

[0131] 1 Head2 Coating robot3 Position detection portion4 Liquid supply portion5 Control unit6 Liquid storage portion7 Air supply portion8 Liquid9 Air regulator10 Base portion11 First arm12 Second arm13 Head unit16 Encoder sensor17 Robot drive portion20 Housing21 Supply port22 Collection port23 Discharge module24 Nozzle240 Nozzle hole25 Nozzle plate250 Nozzle surface26 Nozzle valve27 Piezoelectric element28 Liquid flow path30 Supporting member40 Maintenance device40A First maintenance device40B Second maintenance device41 Cap100 Coating apparatus200 Object201 First region202 Second region211 Moving direction212 W idth direction300 Computer301 RIP unit302 Rendering unit400 Controller401 CPU402 ROM403 RAM404 HDD / SSD405 I / F411 System control unit412 Nozzle valve drive control unit413 Discharge cycle signal generation unit414 Memory control unit415 Data storage unit416 Robot control signal generation unit418 Maintenance / recovery control unit419 Coating route planning unit420 Coating order determination unit500 Head control device600 Robot control device700 A Input deviceS System bus[Citation List][Patent Literature]

[0132] [PTL 1]Japanese Unexamined Patent Application Publication No. 2023-140457

Claims

[CLAIMS]

1. A coating apparatus comprising: a first head having first nozzles to discharge a liquid from the first nozzles to perform a first coating; a second head having second nozzles to discharge a liquid from the second nozzles to perform a second coating; and a controller configured to determining an order of the first coating and the second coating based on at least one of: a discharge time of each of the first head and the second head; a number of each of the first nozzles and the second nozzles; or a waiting time of one of the first head and the second head when another of the first head and the second head discharges the liquid.

2. The coating apparatus according to claim 1, wherein the controller controls the first head to perform the first coating before controlling the second head to perform the second coating, and the controller controls the second head to perform the second coating after controlling the first head to complete the first coating, when the discharge time of the first head is longer than the discharge time of the second head; or when the waiting time of the second head is longer than the waiting time of the second head.

3. The coating apparatus according to claim 2, wherein the controller controls the first head to perform the first coating again after controlling the second head to perform the second coating.

4. The coating apparatus according to claim 1, wherein the controller controls the first head to perform the first coating before controlling the second head to perform the second coating when the number of the first nozzles is smaller than the number of the second nozzles.

5. The coating apparatus according to claim 1, wherein the controller configured to control the first head and the second head to respectively discharge the liquid from the first nozzles and the second nozzles, wherein the controller determines the order of the first coating and the second coating based on at least one of: the discharge time;the number of each of the first nozzles and the second nozzles; or the waiting time of one of the first head and the second head when another of the first head and the second head discharges the liquid.

6. The coating apparatus according to claim 1, wherein the controller determines the discharge time based on a coating time of the first head and the second head, and the controller determines the waiting time based on non-coating time of each of the first head and the second head.

7. The coating apparatus according to claim 5, wherein the controller determines the order of the first coating and the second coating to control a dryness of the first nozzles and the second nozzles to be equal to or less than a threshold.

8. The coating apparatus according to claim 1, wherein the first head includes the first nozzles arrayed in a first direction on a first nozzle surface, the second head includes the second nozzles, arrayed in a second direction different from the first direction, on a second nozzle surface.

9. The coating apparatus according to claim 1, comprising: a maintenance device including a cap to cover the first nozzles in the first head and the second nozzles in the second head, wherein the maintenance device covers the first nozzles in the first head and the second nozzles in the second head with the cap after the first head completes the first coating and the second head completes the second coating.

10. A coating system comprising: the coating apparatus according to any one of claims 1 to 8; and a maintenance device including a cap covering the first nozzles in the first head and the second nozzles in the second head, wherein the controller controls the maintenance device to cover the first nozzles in the first head and the second nozzles in the second head with the caps after controlling the first head to complete the first coating and controlling the second head to complete the second coating.

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