Painting system

Abstract

To provide a coating system that can enhance coating quality by wiping the nozzle formed surface at an appropriate timing.SOLUTION: A painting system 1 comprises: a painting robot 10 including a painting head unit 50 equipped with a painting head 53 having a plurality of nozzles 54 configured to eject droplets of paint, a robot arm R1 attached at a tip thereof with the painting head unit 50 and configured to move the painting head unit 50 to a desired position, and a control unit equipped with a head control unit 90 configured to control operation of the painting head 53 and with a robot arm control unit 70 configured to control operation of the robot arm R1; and wiping means 300 for wiping a nozzle formed surface 52. The robot arm control unit 70 is configured to control the operation of the robot arm R1 so that the nozzle formed surface 52 is wiped by the wiping means 300 at least before painting each vehicle.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a painting system including a painting robot. [Background technology]

[0002] Robotic painting using robots has become mainstream in painting lines for vehicles such as automobiles. As an example of a configuration related to this robotic painting, Patent Document 1, for example, describes that a nozzle discharge surface cleaning means for cleaning the surface of the nozzle discharge surface may be provided. As this nozzle discharge surface cleaning means, Patent Document 1 describes a wiping device that includes a wiper member made of a flexible material such as rubber, and that uses the wiper member to scrape off paint or the like adhering to the nozzle discharge surface. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2021 / 028983 publication (see paragraph 0139 etc.) Summary of the Invention [Problem to be solved by the invention]

[0004] However, the configuration disclosed in Patent Document 1 does not disclose at all the specific timing at which the nozzle formation surface should be wiped, which may result in insufficient improvement in coating quality.

[0005] The present invention has been made in light of the above circumstances, and has as its object to provide a coating system that can improve coating quality by wiping the nozzle formation surface at an appropriate timing. [Means for solving the problem]

[0006] In order to solve the above problems, according to a first aspect of the present invention, there is provided a painting system comprising a painting robot that paints parts of a vehicle, the painting system comprising: a painting head unit having a painting head with a plurality of nozzles that eject droplets of paint; a robot arm that has the painting head unit attached to its tip and moves the painting head unit to a desired position; a head control unit that controls the operation of the painting head; and a control unit that includes a robot arm control unit that controls the operation of the robot arm, the painting robot having a wiping means for wiping the nozzle forming surface where the nozzles are open, and the robot arm control unit controlling the operation of the robot arm so that the nozzle forming surface is wiped by the wiping means at least before painting each vehicle. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a coating system that can improve coating quality by wiping the nozzle formation surface at an appropriate timing. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic diagram showing the overall configuration of a painting robot according to an embodiment of the present invention; [Figure 2] FIG. 2 is a diagram showing a schematic configuration of a painting system including the painting robot shown in FIG. [Figure 3] 2 is a front view of a nozzle forming surface that ejects paint, of a paint head unit provided in the paint robot shown in FIG. 1. FIG. [Figure 4] 2 is a diagram showing a schematic configuration for supplying paint to each nozzle in the painting robot shown in FIG. 1. FIG. [Figure 5] 1 is a cross-sectional view showing the configuration of the vicinity of the column-directional supply flow paths, the nozzle pressurizing chambers, and the column-directional discharge flow paths in the painting robot shown in FIG. [Figure 6] 4 is a plan view showing the configuration of a nozzle formation surface of another paint head unit different from the paint head unit shown in FIG. 3. FIG. [Figure 7] 10 is a diagram showing an image of wiping the nozzle formation surface with a wiping means before painting a vehicle in this embodiment. FIG. [Figure 8] 10 is a diagram showing an image of wiping the nozzle formation surface with the wiping means after painting on the vehicle in this embodiment. FIG. [Figure 9] 10 is a diagram showing an image of wiping the nozzle formation surface with a wiping means between painting passes in this embodiment. FIG. [Figure 10] 10A and 10B are diagrams illustrating an image of wiping the nozzle surface with the wiping means when moving on to painting a different part of the vehicle in this embodiment. [Figure 11] FIG. 10 is a diagram showing an image of wiping the nozzle surface with the wiping means when switching to a different type of coating after a specific type of coating has been completed in this embodiment. [Figure 12] 10 is a diagram showing an image of wiping the nozzle formation surface with the wiping means after the paint head is filled with paint in this embodiment. FIG. [Figure 13] 10 is a diagram showing an image of wiping the nozzle forming surface with the wiping means when the paint head is tilted beyond a predetermined tilt angle in this embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] A coating system 1 and a coating robot 10 according to one embodiment of the present invention will be described below with reference to the drawings. In the following description, where necessary, the X direction will be the longitudinal direction of the nozzle forming surface 52 (painting head 53), the X1 side will be the right side in Fig. 3, and the X2 side will be the left side in Fig. 3. The Y direction will be the lateral direction (width direction) of the nozzle forming surface 52 (painting head 53), the Y1 side will be the upper side in Fig. 3, and the Y2 side will be the lower side in Fig. 3.

[0010] (1. Overview of the Painting System 1 and Painting Robot 10) The painting system 1 and painting robot 10 of this embodiment "paint" objects to be painted, such as vehicles or vehicle parts (hereinafter, vehicle parts that are part of a vehicle will also be described as vehicles) located on a painting line in an automobile manufacturing factory, and are intended to form a paint film on the surface of the object to protect the surface and provide a beautiful appearance. Therefore, it is necessary to paint vehicles moving along the painting line at predetermined intervals within a certain time with the desired painting quality.

[0011] Furthermore, the painting system 1 and painting robot 10 of this embodiment are capable of not only forming the above-mentioned coating film but also forming various designs and images on objects to be painted, such as vehicles and vehicle parts. Note that the objects to be painted are not limited to vehicles and vehicle parts, and may be any parts other than automobiles (for example, exterior parts of airplanes and trains) that require painting.

[0012] (1-1. Overall Configuration of Painting System 1 and Painting Robot 10) Fig. 1 is a schematic diagram showing the overall configuration of a painting robot 10 according to one embodiment of the present invention. Fig. 2 is a diagram showing the schematic configuration of a painting system 1 including the painting robot 10 shown in Fig. 1. As shown in Fig. 2, the painting system 1 includes the painting robot 10, an image processing device 200, and a wiping means 300.

[0013] (1-2. About Painting Robot 10) As shown in Fig. 1, the painting robot 10 mainly comprises a robot body 20 and a painting head unit 50. The painting robot 10 shown in Fig. 1 is, as an example, a six-axis vertical articulated robot, but the painting robot 10 may be any type of robot, such as a vertical articulated type other than six axes, a horizontal articulated type, or an Cartesian robot.

[0014] (1-3. About the robot body 20) 1, the robot main body 20 mainly comprises a base 21, first to sixth rotation shafts 22a to 22f, legs 23, a first rotating arm 24, a second rotating arm 25, a rotating arm 26, a wrist 27, and motors M1 to M6 (see FIG. 2) that drive these components. The portion from the legs 23 to the wrist 27 corresponds to the robot arm R1, but other portions such as the base 21 may also correspond to the robot arm R1.

[0015] Of these, the base 21 is a part that is installed on an installation site such as a floor, but the base 21 may be movable relative to the installation site. The legs 23 are parts that stand upward from the base 21 and are provided so as to be rotatable relative to the base 21 via a first rotation shaft 22a driven by a motor M1 (see FIG. 2). The legs 23 may also be configured not to rotate relative to the base 21.

[0016] A first rotating arm 24 is provided at the upper end of leg 23 so as to be rotatable via second rotating shaft 22b when driven by motor M2. Furthermore, a second rotating arm 25 is provided at the tip end of first rotating arm 24 so as to be rotatable via third rotating shaft 22c when driven by motor M3.

[0017] A rotating arm 26 is provided at the tip of the second rotating arm 25, rotatably about the center axis of the second rotating arm 25. This rotating arm 26 is rotatable via a fourth rotating shaft 22d when driven by a motor M4. A wrist unit 27 is provided at the tip of the rotating arm 26. This wrist unit 27 is capable of rotational movement around a plurality of, e.g., two, differently oriented shafts when driven by motors M5 and M6. In FIG. 1, the rotational shafts capable of this rotational movement are designated as a fifth rotating shaft 22e and a sixth rotating shaft 22f, respectively. This allows for precise control of the orientation of the painting head unit 50. The number of shafts may be any number greater than two.

[0018] Furthermore, the painting head unit 50 is attached to the wrist portion 27, but this painting head unit 50 may be provided so as to be detachable from the wrist portion 27.

[0019] (1-4. Regarding the paint / cleaning liquid supply unit 40) As shown in Fig. 2, the coating system 1 and the coating robot 10 are provided with a paint / cleaning liquid supply unit 40. The paint / cleaning liquid supply unit 40 is a part for supplying paint or cleaning liquid to the coating head unit 50. For this purpose, the paint / cleaning liquid supply unit 40 is equipped with a supply path 41 (see Fig. 4) for supplying paint from a paint reservoir (not shown) or cleaning liquid from a cleaning liquid reservoir (not shown), a pump (not shown), valves (not shown), and a return flow path 42 for recovering paint that has not been ejected or cleaning liquid that has been used for cleaning.

[0020] Here, the paint / cleaning liquid supply unit 40 is provided with a switching control valve 45. The switching control valve 45 is a control valve for switching between supplying paint from a paint reservoir (not shown) and supplying cleaning liquid from a cleaning liquid reservoir (not shown), and is operated under the control of a paint / cleaning liquid supply control unit 80 (described later). By providing such a switching control valve 45, the paint / cleaning liquid supply unit 40 can selectively supply either paint or cleaning liquid.

[0021] In addition, when a configuration is adopted in which paint is supplied from outside the painting robot 10, the painting robot 10 does not need to have a part for storing paint, and may have a part for storing paint outside the painting robot 10.

[0022] (1-5. About the painting head unit) Next, the paint head unit 50 will be described. FIG. 3 is a front view of the nozzle forming surface 52 of the paint head unit 50, from which paint is ejected. As shown in FIG. 3, the paint head unit 50 is equipped with a head cover (not shown), and various components are housed within the head cover. As shown in FIG. 3, the nozzle forming surface 52 is provided with a plurality of nozzle rows 55, in which nozzles 54 are arranged in a direction inclined with respect to the longitudinal direction of the paint head unit 50. In this embodiment, the nozzle rows 55 include a first nozzle row 55A located on one side (Y2 side) in the main scanning direction (Y direction) and a second nozzle row 55B located on the other side (Y1 side) in the main scanning direction.

[0023] When discharging paint, the drive timing of each nozzle 54 is controlled so that droplets discharged from nozzles 54 in the second nozzle row 55B land between droplets discharged from adjacent nozzles 54 in the first nozzle row 55A, thereby improving dot density during coating.

[0024] 3, a single paint head 53 is present on the nozzle forming surface 52. However, the nozzle forming surface 52 may also have a head group made up of a plurality of paint heads 53. In this case, one example is a configuration in which the plurality of paint heads 53 are aligned and arranged in a staggered pattern, but the arrangement of the paint heads 53 in the head group does not have to be staggered.

[0025] Fig. 4 is a diagram showing a schematic configuration for supplying paint to each nozzle 54. Fig. 5 is a cross-sectional view showing the configuration in the vicinity of the column-directional supply flow channel 58, the nozzle pressurizing chamber 59, and the column-directional discharge flow channel 60. As shown in Figs. 4 and 5, the coating head 53 is equipped with a large supply flow channel 57, a column-directional supply flow channel 58, the nozzle pressurizing chamber 59, a column-directional discharge flow channel 60, and a large discharge flow channel 61. The large supply flow channel 57 is a flow channel through which paint is supplied from the supply channel 41. The column-directional supply flow channel 58 is a flow channel into which the paint in the large supply flow channel 57 is diverted.

[0026] Furthermore, the nozzle pressurizing chambers 59 are connected to the column-directional supply channels 58 via the nozzle supply channels 59a. As a result, paint is supplied to the nozzle pressurizing chambers 59 from the column-directional supply channels 58. The nozzle pressurizing chambers 59 are provided in a number corresponding to the number of nozzles 54, and the paint inside can be ejected from the nozzles 54 using a piezoelectric substrate 62, which will be described later.

[0027] The nozzle pressurizing chamber 59 is also connected to the column-directional discharge flow path 60 via the nozzle discharge flow path 59b. Therefore, paint not ejected from the nozzle 54 is discharged from the nozzle pressurizing chamber 59 to the column-directional discharge flow path 60 via the nozzle discharge flow path 59b. The column-directional discharge flow path 60 is also connected to a large discharge flow path 61. The large discharge flow path 61 is a flow path where the paint discharged from each column-directional discharge flow path 60 joins together. This large discharge flow path 61 is connected to the return flow path 42.

[0028] With this configuration, paint supplied from the supply passage 41 passes through the supply-side large flow passage 57, the column-directional supply flow passage 58, the nozzle supply flow passage 59a, and the nozzle pressurizing chamber 59, before being ejected from the nozzle 54. Furthermore, paint that is not ejected from the nozzle 54 passes from the nozzle pressurizing chamber 59 through the nozzle discharge flow passage 59b, the column-directional discharge flow passage 60, and the discharge-side large flow passage 61, and is returned to the return flow passage 42.

[0029] 4, one column-directional supply flow path 58 is arranged to correspond to one column-directional discharge flow path 60. However, a plurality of (for example, two) column-directional discharge flow paths 60 may be arranged to correspond to one column-directional supply flow path 58. Also, a plurality of column-directional supply flow paths 58 may be arranged to correspond to one column-directional discharge flow path 60.

[0030] 5, a piezoelectric substrate 62 is disposed on the ceiling surface of the nozzle pressurizing chamber 59 (the surface opposite to the nozzle 54). The piezoelectric substrate 62 includes two piezoelectric ceramic layers 63a and 63b, which are piezoelectric bodies, and further includes a common electrode 64 and an individual electrode 65. The piezoelectric ceramic layers 63a and 63b are members that can expand and contract when a voltage is applied from the outside. Ferroelectric ceramic materials such as lead zirconate titanate (PZT), NaNbO3, BaTiO3, (BiNa)NbO3, and BiNaNb5O15 can be used for the piezoelectric ceramic layers 63a and 63b.

[0031] As shown in FIG. 5, the common electrode 64 is disposed between the piezoelectric ceramic layer 63a and the piezoelectric ceramic layer 63b. A surface electrode (not shown) for the common electrode is formed on the upper surface of the piezoelectric substrate 62. The common electrode 64 and the surface electrode for the common electrode are electrically connected through a through conductor (not shown) in the piezoelectric ceramic layer 63a. The individual electrodes 65 are disposed in positions facing the nozzle pressurizing chamber 59. The portion of the piezoelectric ceramic layer 63a sandwiched between the common electrode 64 and the individual electrode 65 is polarized in the thickness direction. Therefore, when a voltage is applied to the individual electrode 65, the piezoelectric ceramic layer 63a is distorted due to the piezoelectric effect. Therefore, when a predetermined drive signal is applied to the individual electrode 65, the piezoelectric ceramic layer 63b moves relatively to the nozzle pressurizing chamber 59, reducing the volume of the nozzle pressurizing chamber 59, thereby ejecting paint.

[0032] 5, the common electrode 64 is arranged on the ceiling surface of the nozzle pressurizing chamber 59, but the common electrode 64 is not limited to being arranged on the ceiling surface of the nozzle pressurizing chamber 59 as shown in Fig. 5. For example, the common electrode 64 may be arranged on a side surface of the nozzle pressurizing chamber 59 (a surface perpendicular or nearly perpendicular to the ceiling surface), or any other configuration may be adopted as long as the paint can be ejected from the nozzle 54 satisfactorily.

[0033] (1-6. Other configurations of the painting head unit) Next, another configuration of the paint head unit 50 will be described. FIG. 6 is a plan view showing the configuration of the nozzle formation surface 52 of another paint head unit 50. As shown in FIG. 6, a nozzle row 55 may be formed by arranging a plurality of nozzles 54 along the short side direction (width direction; Y direction) of the paint head 53. Note that in the configuration shown in FIG. 6, the nozzle row 55 is formed by arranging a plurality of nozzles 54 along the short side direction (width direction; main scanning direction) of the paint head 53. However, a configuration in which only one (single) nozzle 54 is arranged in the short side direction (width direction; main scanning direction) of the paint head 53 may also be used. In other words, the nozzle row 55 may be formed by a single nozzle 54.

[0034] Furthermore, when painting a vehicle using a paint head 53 such as that shown in Fig. 6, painting may be performed with the longitudinal direction of the paint head 53 slightly tilted relative to the main scanning direction of the paint head 53. For example, in the configuration of the paint head 53 shown in Fig. 3, if the nozzle rows 55 are tilted at a predetermined angle relative to the main scanning direction, then the shorter side of the paint head 53 shown in Fig. 6 can be tilted at a predetermined angle relative to the main scanning direction of the paint head 53. When tilted in this way, painting equivalent to that achieved by the paint head 53 shown in Fig. 3 can be achieved simply by adjusting the timing at which paint is ejected from each nozzle 54.

[0035] (1-7. Control configuration of painting system 1) Next, a description will be given of the control configuration for controlling the operation of the painting system 1. The control configuration described below corresponds to the control unit. As shown in FIG. 2, the painting robot 10 includes a robot arm control unit 70, a paint / cleaning liquid supply control unit 80, a head control unit 90, and a main control unit 100. The painting robot 10 is also connected to an image processing device 200 and further includes a wiping means 300, thereby constituting the painting system 1.

[0036] The robot arm control unit 70, the paint / cleaning liquid supply control unit 80, the head control unit 90, the main control unit 100, and the image processing unit 210 (described later) are each composed of a CPU (Central Processing Unit), memory such as a storage unit (ROM (Read Only Memory), RAM (Random Access Memory), non-volatile memory, etc.), and other elements. The image processing unit 210 may use a GPU (Graphics Processing Unit) together with or instead of a CPU with excellent image processing performance.

[0037] The painting robot 10 also has various sensors (not shown), and outputs from these sensors are input to one of the robot arm control unit 70, the paint / cleaning liquid supply control unit 80, the head control unit 90, and the main control unit 100. Examples of the various sensors include acceleration sensors, angular velocity sensors, position detection sensors that detect the position of each driving unit, and image sensors, but other sensors may also be used.

[0038] Of these, the robot arm control unit 70 is a part that controls the driving of the above-mentioned motors M1 to M6. The robot arm control unit 70 is provided with a memory 71, which stores programs and data created by robot teaching.

[0039] The robot arm control unit 70 controls the driving of the motors M1 to M6 based on the programs and data stored in the memory 71 and the image processing by the image processing unit 210 of the image processing device 200. This control allows the paint head unit 50 to pass through desired positions for painting at a desired speed and stop at a predetermined position. Note that the memory 71 may be provided in the paint robot 10, but it may also be external to the paint robot 10, and information may be sent and received to the memory 71 via wired or wireless communication means.

[0040] The paint / cleaning liquid supply control unit 80 is a part that controls the supply of paint or cleaning liquid to the painting head unit 50, and specifically controls the operation of the pumps and valves provided in the paint / cleaning liquid supply unit 40. The paint / cleaning liquid supply control unit 80 also controls the operation of the switching control valve 45 to enable either paint or cleaning liquid to be selectively supplied from a paint reservoir (not shown) or a cleaning liquid reservoir (not shown).

[0041] It is preferable that the paint / cleaning liquid supply control unit 80 controls the operation of the pumps and valves so that the paint or cleaning liquid is supplied at a constant pressure to the painting head unit 50. The paint / cleaning liquid supply control unit 80 corresponds to a pressure control unit.

[0042] The head control unit 90 is a part that controls the operation of the piezoelectric substrate 62 in the painting head unit 50 based on the image processing in the image processing unit 210.

[0043] The main control unit 100 is a part that transmits predetermined control signals to the robot arm control unit 70, the paint and cleaning liquid supply control unit 80, and the head control unit 90, so that the motors M1 to M6, the paint and cleaning liquid supply unit 40, and the piezoelectric substrate 62 work together to paint the object to be painted.

[0044] The painting system 1 is also provided with an image processing device 200. The image processing device 200 includes an image processing unit 210 and a memory 220. The image processing unit 210 is a part that creates image data for each painting pass, which is a path along which the painting head 53 performs painting.

[0045] The memory 220 stores image data for each painting pass in accordance with the painting sequence.

[0046] The image processing device 200 corresponds to, for example, a computer, but the computer may be a component of the painting robot 10 or may be provided separately from the painting robot 10. When the image processing device 200 is provided separately from the painting robot 10, data is transmitted and received between the image processing device 200 and the painting robot 10 via wired or wireless communication. Even if the image processing device 200 is provided separately from the painting robot 10, it may or may not be included in the concept of the painting robot 10.

[0047] (1-8. Regarding the wiping means 300) Next, we will explain the wiping means 300. The wiping means 300 is provided outside the painting line where the painting of the vehicle is performed by the painting head 53 (i.e., in a location that does not interfere with the area of ​​the vehicle being painted). The wiping means 300 is a means for wiping the nozzle forming surface 52, and includes, for example, at least one of a wire, a sponge, etc.

[0048] The wiping means 300 includes, for example, a long or flat wiping portion 310 in order to wipe the nozzle forming surface 52. Therefore, the nozzle forming surface 52 can be wiped by operating the robot arm R1 to move the nozzle forming surface 52 while the nozzle forming surface 52 is in contact with the wiping portion.

[0049] (2. About the action) The operation of the painting system 1 and painting robot 10 configured as above will be described below.

[0050] (a) Wiping of the nozzle forming surface 52 before painting the vehicle C1 In the paint head 53 shown in Figure 5, if droplets that have overflowed from the openings of the nozzles 54 adhere to the nozzle forming surface 52 before painting a vehicle C1 (see Figure 7), there is a risk that the droplets will be caught up in the nozzles 54 when they are ejected. In this case, the size of the droplets may change or the droplets may land in a position different from the intended landing position, which could result in a deterioration in paint quality. Furthermore, if droplets that have overflowed from the nozzles 54 adhere to the periphery of the openings of the nozzles 54, the ejection of droplets from the nozzles 54 may be hindered, making it difficult for the droplets to be ejected.

[0051] Therefore, in this embodiment, as shown in FIG. 7, the nozzle forming surface 52 is wiped by wiping means 300 before painting each vehicle C1.

[0052] To wipe the nozzle forming surface 52, the robot arm control unit 70 operates the robot arm R1 in response to a command from the main control unit 100 to move the painting head 53 outside the painting line where painting is performed. Then, the robot arm control unit 70 presses the nozzle forming surface 52 against the wiping unit 310 of the wiping means 300 provided outside the painting line, and moves the nozzle forming surface 52 while maintaining the pressed state. This causes the wiping means 300 (wiping unit 310) to wipe the nozzle forming surface 52.

[0053] By wiping with the wiping means 300, paint adhering to the nozzle forming surface 52 is removed before painting the vehicle C1. Therefore, when droplets are discharged from the nozzles 54 to paint the vehicle C1, the discharge of droplets is prevented from entraining paint adhering to the nozzle forming surface 52. This makes it possible to improve the painting quality of the vehicle C1.

[0054] In the following description, similarly to the above, the robot arm control unit 70 operates the robot arm R1 in response to a command from the main control unit 100 to press the nozzle forming surface 52 against the wiping portion 310 of the wiping means 300, and moves the nozzle forming surface 52 while maintaining the pressed state. As a result, the nozzle forming surface 52 is wiped by the wiping means 300 (wiping portion 310).

[0055] (b) Wiping of the nozzle forming surface 52 after painting of the vehicle C1 When the nozzle forming surface 52 is wiped as described above before painting the vehicle C1, a certain amount of time may pass before painting the next vehicle C1. If such a time passes, there is a risk that the droplets adhering to the nozzle forming surface 52 will dry and solidify. In that case, even if the nozzle forming surface 52 is wiped with the wiping means 300 before painting the next vehicle C1, there is a risk that the solidified droplets will not be removed.

[0056] 8, the nozzle forming surface 52 may be wiped by the wiping means 300 after painting of the vehicle C1 is completed. However, if the time between the completion of painting of one vehicle C1 and the start of painting of the next vehicle C1 is not particularly long, wiping of the nozzle forming surface 52 by the wiping means 300 after painting of the vehicle C1 may be omitted. Furthermore, if the time between the completion of painting of one vehicle C1 and the start of painting of the next vehicle C1 is longer than the above, the nozzle forming surface 52 may be periodically wiped by the wiping means 300 to prevent it from drying out.

[0057] (c) Wiping the nozzle forming surface 52 between painting passes Furthermore, when painting the vehicle C1 in multiple painting passes, the nozzle forming surface 52 may be wiped with the wiping means 300 after one painting pass is completed and before the next painting pass begins, as shown in Figure 9. In this case, if painting is performed in only one direction while the painting head 53 is reciprocating, it is preferable to wipe the nozzle forming surface 52 with the wiping means 300 after each painting pass is completed.

[0058] However, if the wiping means 300 were to wipe the nozzle forming surface 52 after each paint pass, it could take a long time to finish painting one vehicle C1. Therefore, multiple paint passes may be grouped into one paint pass section, and the wiping means 300 may be used to wipe the nozzle forming surface 52 after each paint pass section is finished.

[0059] Furthermore, even when the painting head 53 paints in both directions of its reciprocating movement, the wiping means 300 may be configured to wipe the nozzle forming surface 52 each time painting is completed on the outbound painting pass and the return painting pass.

[0060] However, if the wiping means 300 were to wipe the nozzle forming surface 52 after each outbound painting pass and each inbound painting pass, it could take too much time to finish painting one vehicle C1. Therefore, it would be possible to treat each round-trip painting pass as one painting pass section, and have the wiping means 300 wipe the nozzle forming surface 52 after each painting pass section. Alternatively, it would be possible to treat multiple painting passes as one painting pass section, regardless of whether they are outbound painting passes or inbound painting passes, and have the wiping means 300 wipe the nozzle forming surface 52 after each painting pass section.

[0061] (d) Wiping the nozzle forming surface 52 when transferring to painting a different part of the vehicle C1 10, when painting using the same paint, the nozzle forming surface 52 may be wiped with the wiping means 300 after painting a specific area is completed and before painting a different area is started. An example of such a case is when the right side of the vehicle C1 is painted, the nozzle forming surface 52 is then wiped with the wiping means 300, and after that wiping, the left side of the vehicle C1 is painted. Another example is when the nozzle forming surface 52 is wiped with the wiping means 300 between painting the front side and the rear side of the vehicle C1. However, this is not limited to the above, as long as it is before painting a different area.

[0062] (e) Wiping the nozzle forming surface 52 when switching to a different type of coating after finishing coating a specific type of coating. 11, the nozzle forming surface 52 may be wiped with the wiping means 300 after a specific type of coating is completed and before a different type of coating is started. An example of such a case is when, after a roof, hood, or other portion is painted with a solid coat, high-resolution painting (printing) such as letters, logos, or marks is to be performed, and the nozzle forming surface 52 is wiped with the wiping means 300 before the high-resolution painting (printing) is performed. However, the present invention is not limited to such a case.

[0063] FIG. 11 shows the state in which the designed letters (logo) "4WD TURBO" are printed after painting of the rear portion of the vehicle C1 is completed.

[0064] (f) Wiping the nozzle forming surface 52 after filling the coating head 53 with coating material Furthermore, when the paint head 53 is filled with paint, the paint often overflows from the nozzles 54, leaving droplets of paint adhering to the nozzle forming surface 52. Therefore, as shown in Figure 12, when the main control unit 100 determines that the paint head 53 has been filled with paint, the nozzle forming surface 52 may be wiped by a wiping means 300. Note that the left side of Figure 12 also shows an image of paint being supplied to the paint head 53 from the paint tank 110 via the paint / cleaning liquid supply unit 40.

[0065] (g) Wiping of the nozzle forming surface 52 when the coating head 53 is tilted beyond a predetermined angle Furthermore, if the tilt angle of the coating head 53 becomes large, there is a risk that paint will be ejected from the nozzles 54 due to the difference in head pressure. Therefore, as shown in Figure 13, when the coating head 53 is tilted beyond a predetermined angle, the nozzle forming surface 52 may be wiped by a wiping means 300.

[0066] In particular, when the paint head 53 is tilted in the longitudinal direction (X direction in FIG. 3), the difference in elevation within the paint head 53 becomes large, so when the tilt angle of the paint head 53 in the longitudinal direction exceeds a predetermined angle, it is preferable to wipe the nozzle forming surface 52 with the wiping means 300. However, when the tilt angle of the paint head 53 in the lateral direction (Y direction in FIG. 3) exceeds a predetermined angle, the nozzle forming surface 52 may also be wiped with the wiping means 300.

[0067] (h) Wiping of the nozzle forming surface 52 based on the paint supply pressure to the coating head 53 Depending on the type of paint used in painting, it may be necessary to set the paint recovery pressure stronger than the paint supply pressure to the paint head 53. In such cases, there is a high possibility that air will be sucked in through the nozzles 54, making it easier for air bubbles to form. Therefore, with such types of paint, it is preferable to control the droplet discharge that causes paint to be discharged from the nozzles 54 before wiping the surface of the nozzle forming surface 52, and then wipe the nozzle forming surface 52 with the wiping means 300 (wiping unit 310).

[0068] (3. Supplementary Note) The contents described in the above-described embodiment can be understood, for example, as follows. [1] That is, the painting system 1 includes a painting robot 10 that paints the painting parts of a vehicle, the painting robot 10 including a painting head unit 50 having a painting head 53 with a plurality of nozzles 54 that eject paint droplets, a robot arm R1 that has the painting head unit 50 attached to its tip and moves the painting head unit 50 to a desired position, a head control unit 90 that controls the operation of the painting head 53, and a robot arm control unit 70 that controls the operation of the robot arm R1, and the painting robot 10 includes a wiping means 300 for wiping the nozzle forming surface 52 where the nozzles 54 open, and the robot arm control unit 70 controls the operation of the robot arm R1 so that the nozzle forming surface 52 is wiped by the wiping means 300 at least before painting each vehicle C1.

[0069] In this way, the wiping operation of the nozzle forming surface 52 by the wiping means 300 is performed at least before painting of each vehicle C1. Therefore, even if droplets overflow and adhere to the nozzle forming surface 52, the droplets adhering to the nozzle forming surface 52 can be removed. Therefore, it is possible to prevent droplets adhering to the nozzle forming surface 52 from being drawn in and ejected, thereby improving the painting quality of the vehicle C1.

[0070] [2] In addition to the above-described embodiment [1], it is preferable that the robot arm control unit 70 controls the operation of the robot arm R1 so that the nozzle forming surface 52 is wiped by the wiping means 300 after painting each vehicle C1.

[0071] When configured in this manner, the wiping means 300 can effectively remove droplets that have adhered to the nozzle forming surface 52 due to wiping back when painting the vehicle C1, or droplets that have overflowed onto the nozzle forming surface 52 during painting.

[0072] [3] In addition to the above-described embodiments, in addition to the contents of [1] and [2], or a combination thereof, it is preferable that the robot arm control unit 70 controls the operation of the robot arm R1 so that the nozzle forming surface 52 is wiped by the wiping means 300 when painting of a specific painting pass among the multiple painting passes used to paint the vehicle C1 is completed and the next painting pass is started.

[0073] By controlling in this manner, droplets that have adhered to the nozzle forming surface 52 during painting in a particular painting pass can be effectively removed by the wiping means 300. As a result, in painting in the next painting pass, droplets adhering to the nozzle forming surface 52 can be prevented from being drawn in and ejected, thereby improving painting quality.

[0074] [4] In addition to the above-described embodiment, in addition to any one of the above-described items [1] to [3] or a combination thereof, it is preferable that the robot arm control unit 70 controls the operation of the robot arm R1 so that the nozzle forming surface 52 is wiped by the wiping means 300 when painting a specific painting area using the same paint and then moving on to painting a different painting area, or when painting a specific type of paint and then moving on to a different type of paint.

[0075] In this way, when painting using the same paint, droplets adhering to the nozzle forming surface 52 can be effectively removed by the wiping means 300 while painting a specific painting area is completed and then moving on to painting a different painting area.

[0076] Furthermore, after a particular type of coating is completed and before a different type of coating is started, droplets adhering to the nozzle forming surface 52 can be effectively removed by the wiping means 300.

[0077] [5] In addition to the above-described embodiment, in addition to any of the above-described items [1] to [4] or a combination thereof, when the main control unit 100 determines that paint has been filled into the painting head 53, it is preferable that the robot arm control unit 70 controls the operation of the robot arm R1 so that the nozzle forming surface 52 is wiped by the wiping means 300.

[0078] In this way, by wiping the nozzle forming surface 52 with the wiping means 300 after filling the paint into the paint head 53, droplets adhering to the nozzle forming surface 52 can be effectively removed by the wiping means 300. This prevents the paint from drying out before painting the vehicle C1, which can lead to a situation where the paint cannot be sufficiently wiped off by wiping before painting.

[0079] [6] In addition to any of the above-mentioned items [1] to [5] or a combination thereof, in the above-mentioned embodiment, when the robot arm control unit 70 tilts the painting head 53 beyond a predetermined angle, it is preferable that the robot arm control unit 70 controls the operation of the robot arm R1 so that the nozzle forming surface 52 is wiped by the wiping means 300.

[0080] In this way, when the robot arm control unit 70 tilts the painting head 53 beyond a predetermined angle and paint is ejected from the nozzle 54 due to a head pressure difference, the wiping means 300 can effectively remove droplets adhering to the nozzle surface 52. This prevents the paint from drying out before painting the vehicle C1, making it impossible to sufficiently wipe off the paint before painting.

[0081] (4. Modifications) Although one embodiment of the present invention has been described above, the present invention can be modified in various ways other than the above embodiment. Modifications will be described below.

[0082] In the above-described embodiment, the paint head 53 employs an inkjet system that ejects droplets from the nozzles 54 using the piezoelectric substrate 62. However, the paint head is not limited to the inkjet system, and a dispenser system may also be used. [Explanation of symbols]

[0083] 1...painting system, 10...painting robot, 20...robot body, 21...base, 22a...first rotating shaft, 22b...second rotating shaft, 22c...third rotating shaft, 22d...fourth rotating shaft, 22e...fifth rotating shaft, 22f...sixth rotating shaft, 23...leg, 24...first rotating arm, 25...second rotating arm, 26...rotating arm, 27...wrist section, 40...paint / cleaning liquid supply section, 41...supply path, 42...return path, 45...switching control valve, 50...painting head unit, 52...nozzle forming surface, 53...painting head, 54...nozzle, 55...nozzle row, 55A...first nozzle row, 55B...second nozzle row, 57...supply-side large flow path, 58...column-directional supply flow path, 59...nozzle pressurizing chamber, 59a...nozzle supply flow path, 59b...nozzle discharge flow path, 60...column-directional discharge flow path, 61...discharge-side large flow path, 62...piezoelectric substrate, 63a...piezoelectric ceramic layer, 63b...piezoelectric ceramic layer, 64...common electrode, 65...individual electrode, 70...robot arm control unit, 71...memory, 80...paint / cleaning liquid supply control unit (corresponding to pressure control unit), 90...head control unit, 100...main control unit, 110...paint tank, 200...image processing device, 210...image processing unit, 220...memory, 300...wiping means, 310...wiping unit

Claims

1. A painting system including a painting robot that paints a painting portion of a vehicle, a paint head unit including a paint head having a plurality of nozzles for ejecting paint droplets; a robot arm having the painting head unit attached to its tip and moving the painting head unit to a desired position; the painting robot is provided with a control unit including a head control unit that controls the operation of the painting head and a robot arm control unit that controls the operation of the robot arm, a wiping means for wiping a nozzle forming surface on which the nozzles are opened, The robot arm control unit and controlling the operation of the robot arm so that the nozzle forming surface is wiped by the wiping means at least before painting each vehicle. A coating system characterized by:

2. 2. The coating system of claim 1, The robot arm control unit and controlling the operation of the robot arm so that the nozzle forming surface is wiped by the wiping means after painting each vehicle. A coating system characterized by:

3. 2. The coating system of claim 1, The robot arm control unit and controlling the operation of the robot arm so that the nozzle forming surface is wiped by the wiping means during a period when painting of a specific painting pass among a plurality of painting passes for painting the vehicle is completed and a transition to a next painting pass is made. A coating system characterized by:

4. 2. The coating system of claim 1, The robot arm control unit and controlling the operation of the robot arm so that the nozzle forming surface is wiped by the wiping means during painting using the same paint, while painting a specific painting area is completed and then a different painting area is started, or while painting a specific type of painting is completed and then a different type of painting is started. A coating system characterized by:

5. 2. The coating system of claim 1, When the control unit determines that the paint has been filled into the painting head, the robot arm control unit controls the operation of the robot arm so that the nozzle forming surface is wiped by the wiping means. A coating system characterized by:

6. 2. The coating system of claim 1, When the robot arm control unit tilts the painting head beyond a predetermined angle, the robot arm control unit controls the operation of the robot arm so that the nozzle forming surface is wiped by the wiping means. A coating system characterized by:

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