Painting robot cleaning system

Abstract

Provided is a cleaning system for a painting robot that can improve the cleanliness of the nozzles and internal flow paths of the painting head without requiring a large-scale dedicated device for cleaning. The cleaning system (1) of a painting robot (10) includes a painting head unit (30) including a painting head (31); a robot arm (R1) that moves the painting head unit; a cover (93) that seals a nozzle formation surface (32); a cover movement mechanism (94) that moves the nozzle formation surface relative to the cover; a paint supply path (52) that supplies paint or a cleaning fluid to the painting head; a return flow path (53) that recovers the paint or cleaning fluid; a pressurization mechanism that pressurizes the cleaning fluid; and a control mechanism that controls the operation of the pressurization mechanism. The control mechanism controls the operation of the cover movement mechanism (94) so that the nozzle formation surface is sealed by the cover and controls the operation of the pressurization mechanism so that the cleaning fluid is supplied to the internal flow path (36) in a pressurized state.

Description

Technical Field

[0001] This invention relates to a cleaning system for painting robots. Background Technology

[0002] Among painting robots for painting vehicles, there are painting robots such as the one shown in Patent Document 1. In Patent Document 1, the paint is controlled to be sprayed from the nozzle (12) by driving a piezoelectric type control unit (132) and moving the needle (122) via a rod (134).

[0003] Furthermore, Patent Document 1 discloses a cleaning station (30) for cleaning nozzles (12). The cleaning station (30) includes multiple housings (32), multiple injectors (38) communicating with the housings (32), and a channel (36) supplied with cleaning fluid from a hose (40) and communicating with the injectors (38). With the above structure, it is possible to clean the nozzles (12) including the discharge port (127).

[0004] In addition, Patent Document 2 discloses a structure that includes a jet inspection device and a cleaning device (4) and is capable of inspecting and cleaning the printhead (1). Existing technical documents Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-182933 Patent Document 2: Japanese Patent Application Publication No. 2022-518341 Summary of the Invention

[0006] Furthermore, in the structure disclosed in Patent Document 1, the inside of the nozzle (12) is cleaned by supplying cleaning fluid from the cleaning station (30). Therefore, a dedicated cleaning station (30) with a complex structure is required, making the structure large-scale.

[0007] Furthermore, in the head (10) disclosed in Patent Document 1, the number of nozzles (12) is small, totaling eight. Therefore, there is no disclosure regarding a type of cleaning with a large number of nozzles arranged in the main scanning direction and the sub-scanning direction, and having an internal flow path corresponding to the large number of nozzles.

[0008] Furthermore, Patent Document 2 also does not disclose a type of cleaning system that has a plurality of nozzles arranged in the main scanning direction and the sub-scanning direction and has an internal flow path corresponding to the plurality of nozzles.

[0009] The present invention is made based on the above-mentioned reasons, and aims to provide a cleaning system for a painting robot that can improve the cleanliness of the nozzles and internal flow paths of the painting head without requiring large-scale special equipment for cleaning.

[0010] To address the aforementioned issues, according to a first aspect of the present invention, a cleaning system for a painting robot is provided, characterized in that the painting robot paints the painting areas of a vehicle, and the cleaning system comprises: a painting head unit having a painting head with a plurality of nozzles for ejecting paint droplets arranged in a main scanning direction and a sub-scanning direction, and having a plurality of internal flow paths for supplying paint or cleaning fluid to the nozzles; a robot arm having the painting head unit mounted at its front end and for moving the painting head unit to a desired position; a cover sealing the nozzle forming surface, with the nozzle exposed at the nozzle forming surface; and a cover moving mechanism. The system comprises: a cover that moves relative to the nozzle forming surface to achieve a sealing state of the nozzle forming surface; a paint supply path that supplies paint or cleaning fluid toward the coating head; a return flow path that connects to the paint discharge side of the coating head and recovers paint or cleaning fluid that has not been ejected from the nozzle; a pressurizing mechanism that pressurizes the cleaning fluid supplied toward the coating head in at least one of the paint supply path and the return flow path; and a control mechanism that controls the operation of the pressurizing mechanism, which in turn controls the operation of the cover moving mechanism to seal the nozzle forming surface through the cover and controls the operation of the pressurizing mechanism to supply cleaning fluid to the internal flow path under pressurization. Invention Effects

[0011] According to the present invention, a cleaning system for a painting robot can be provided that does not require large-scale dedicated equipment for cleaning and can improve the cleanability of the nozzles and internal flow paths of the painting head. Attached Figure Description

[0012] Figure 1 This is a schematic diagram illustrating the overall structure of a painting robot according to one embodiment of the present invention. Figure 2 It means Figure 1 The diagram shows a schematic structure of the cleaning system for the painting robot. Figure 3 It means to observe from the front. Figure 1 The diagram shows the state of the nozzles that spray paint onto the coating head unit of the coating robot. Figure 4 It means and Figure 3 The diagram shows a plan view of the nozzle forming surface structure, which differs from other coating head units. Figure 5 It means to Figure 1 The diagram shows a schematic structure of the coating head of a painting robot, illustrating the supply of paint to each nozzle. Figure 6 It means to indicate Figure 1 The diagram shows a schematic representation of the control structure centered on the control unit of the cleaning system of the painting robot. Figure 7 It means Figure 1 The diagram shows the cleaning process of the internal flow path within the painting head of the painting robot. Figure 8 This is a diagram showing the schematic structure of a modified cleaning system. Explanation of reference numerals in the attached figures 1: Cleaning system; 2: Nozzle forming surface; 10: Painting robot; 20: Robot body; 21: Base; 22a: First rotating axis; 22b: Second rotating axis; 22c: Third rotating axis; 22d: Fourth rotating axis; 22e: Fifth rotating axis; 22f: Sixth rotating axis; 23: Leg; 24: First rotating arm; 25: Second rotating arm; 26: Rotating arm; 27: Wrist; 30: Painting head unit; 31: Painting head; 32: Nozzle forming surface; 33: Nozzle; 34: Nozzle array; 34A: First nozzle array; 34 B: Second nozzle row; 35: Piezoelectric substrate; 36: Internal flow path; 37: Nozzle pressurization chamber; 50: Paint supply and cleaning mechanism; 51: Paint circulation path; 52: Paint supply path; 53: Return flow path; 54: Bypass flow path; 55: External supply path; 56: Second bypass flow path; 57: Paint tank; 58: Removal filter; 59: Degassing module; 61: Supply pump; 62: Suction pump; 63: Cleaning tank; 64: Delivery pump (corresponding to pressurization mechanism, first pressurization mechanism, or second pressurization mechanism); 65: Drainage tank; 66: Compression. Machine, 67: Cleaning switching valve, 67a~67c: Valve section, 71: First three-way valve, 72: Second three-way valve, 73: Third three-way valve, 74: Fourth three-way valve, 81: First switching valve, 81a~81d: Valve section, 82: Second switching valve, 82a~82d: Valve section, 83: Third switching valve, 83a~83d: Valve section, 84: Fourth switching valve, 84a~84f: Valve section, 85: Fifth switching valve, 85a~85f: Valve section, 86: Sixth switching valve, 86a~86d: Valve section, 91: First vacuum jet 92: Second vacuum ejector (corresponding to suction mechanism, first suction mechanism, or second suction mechanism), 93: Cover, 94: Cover moving mechanism, 95: Vacuum ejector (corresponding to cleaning suction mechanism), 100: Control unit (corresponding to control mechanism), 110: Main control unit (corresponding to control mechanism), 120: Robot arm control unit, 130: Head control unit, 140: Paint supply control unit, 150: Cleaning control unit (corresponding to control mechanism), R1: Robot arm Detailed Implementation

[0013] Hereinafter, a cleaning system 1 of a painting robot 10 according to one embodiment of the present invention will be described with reference to the accompanying drawings. It should be noted that the cleaning system 1 cleans the painting system, which performs painting by spraying paint onto the object to be painted. Therefore, the cleaning system 1 is also equivalent to the painting system that performs the painting onto the object to be painted.

[0014] Additionally, in the following description, as needed, the X direction is defined as the long side direction of the nozzle forming surface 32 (coating head 31), and the X1 side is defined as... Figure 3 On the right side of the middle, the X2 side is set as Figure 3 On the left side of the nozzle forming surface 32 (coating head 31). Additionally, the Y direction is set as the short side direction (width direction) of the nozzle forming surface 32 (coating head 31), and the Y1 side is set as... Figure 3 On the upper side of the paper, the Y2 side is set as Figure 3 The bottom side of the paper.

[0015] (1. Overview of Painting Robot 10) The cleaning system 1 of this embodiment "coats" vehicles or vehicle components (hereinafter, vehicle components that will also be part of a vehicle will be described as vehicles) located on the painting production line of an automobile manufacturing plant, with the purpose of forming a coating film on the surface of the object to be coated, thus providing protection and aesthetics to the surface. Therefore, it is necessary to coat vehicles moving along the painting production line with the desired coating quality at predetermined intervals.

[0016] Furthermore, in the cleaning system 1 of this embodiment, not only can the above-mentioned coating be formed, but various designs and images can also be formed on objects to be coated, such as vehicles and vehicle components. It should be noted that the objects to be coated are not limited to vehicles and vehicle components, but can also be various components other than automobiles (for example, the exterior components of airplanes and trains), as long as they are objects that need to be coated.

[0017] (1-1. Overall structure of the cleaning system 1 of the painting robot 10) Figure 1 This is a schematic diagram showing the overall structure of a painting robot 10 according to one embodiment of the present invention. Figure 2 It means Figure 1 A schematic diagram of the cleaning system 1 of the painting robot 10 is shown. Figure 1 and Figure 2 As shown, the cleaning system 1 includes a painting robot 10 and a paint supply and cleaning mechanism 50.

[0018] (1-2. About the painting robot 10) like Figure 1As shown, the painting robot 10 uses the robot body 20 and the painting head unit 30 as its main components. Figure 1 The painting robot 10 shown is an example of a 6-axis vertical multi-joint robot, but the painting robot 10 can also be any type of robot other than a 6-axis vertical multi-joint type, horizontal multi-joint type, orthogonal robot, etc.

[0019] The robot body 20 comprises a base 21, first to sixth rotation axes 22a to 22f, legs 23, a first rotating arm 24, a second rotating arm 25, a rotating arm 26, a wrist 27, and motors (not shown) that drive them. It should be noted that the portion from the legs 23 to the wrist 27 corresponds to the robot arm R1, but it is also possible that other portions such as the base 21 also correspond to the robot arm R1.

[0020] The base 21 is a part that is installed on the ground or other installation location, but the base 21 can also move relative to the installation location. The leg 23 is a part that stands upright from the base 21, and is configured to rotate relative to the base 21 via a first rotation axis 22a driven by a motor (not shown). Alternatively, the leg 23 can be configured not to rotate relative to the base 21.

[0021] Furthermore, the first rotating arm 24 is rotatably mounted on the upper end of the leg 23 via a motor (not shown) and via a second rotating shaft 22b. Moreover, the second rotating arm 25 is rotatably mounted on the front end side of the first rotating arm 24 via a motor (not shown) and via a third rotating shaft 22c.

[0022] Furthermore, a rotating arm 26 is rotatably mounted on the front end of the second rotating arm 25, capable of rotating about the central axis of the second rotating arm 25. This rotating arm 26 is driven by a motor (not shown) and rotates via a fourth rotating shaft 22d. Additionally, a wrist 27 is provided on the front end of the rotating arm 26. This wrist 27 is capable of rotating about, for example, two or more shafts with different orientations, driven by a motor (not shown). Figure 1 In this design, the rotating axes capable of rotational movement are designated as the 5th rotating axis 22e and the 6th rotating axis 22f. This allows for high-precision control of the orientation of the coating head unit 30. It should be noted that the number of axes can vary as long as there are two or more.

[0023] In addition, a painting head unit 30 is installed on the wrist 27, which can also be freely installed and removed from the wrist 27.

[0024] (1-3. Regarding the painting head unit 30) Next, the painting head unit 30 of the painting robot 10 will be described. Figure 3 This diagram shows the state of the nozzles that spray paint into the coating head 31 of the coating head unit 30, as viewed from the front, forming a surface 32. (See diagram below.) Figure 3 As shown, the coating head unit 30 has a head cover (not shown), inside which various structures such as the coating head 31 are built. In addition, the coating head 31 is provided with multiple nozzles 33 for spraying paint.

[0025] like Figure 3 As shown, on the side of the coating head 31 where the paint is sprayed (nozzle forming surface 32), the openings of multiple nozzles 33 are exposed. It should be noted that in the following description, the openings of the nozzles 33 are also referred to as nozzles 33.

[0026] Furthermore, a plurality of nozzle rows 34 are provided in the nozzle forming surface 32, and the nozzle rows 34 are formed by arranging the nozzles 33 in a direction inclined relative to the long side direction of the coating head unit 30. In this embodiment, the above-mentioned nozzle rows 34 include a first nozzle row 34A located on one side (Y2 side) of the main scanning direction (Y direction) and a second nozzle row 34B located on the other side (Y1 side) of the main scanning direction.

[0027] Furthermore, when spraying paint, the driving timing of each nozzle 33 is controlled so that droplets sprayed from the nozzle 33 in the second nozzle row 34B fall between droplets sprayed from adjacent nozzles 33 in the first nozzle row 34A. This allows for increased dot density during coating.

[0028] Furthermore, the cover 93, described later, can be sealed relative to the outside by abutting against the nozzle forming surface 32. In this state, the cleaning operation described later can be achieved by activating the first vacuum ejector 91 or the second vacuum ejector 92, described later.

[0029] In addition, Figure 3 In the structure shown, the arrangement of nozzles 33 in the first nozzle row 34A and the second nozzle row 34B is inclined relative to the short side direction (Y direction; main scanning direction) of the coating head 31. However, such an arrangement of nozzles 33 is not required. For example, the nozzle row 34 may be configured along the short side direction (Y direction) of the coating head 31. Alternatively, the nozzle row 34 may be a single nozzle row 34 in the short side direction (Y direction; main scanning direction) of the coating head 31, without being divided into the first nozzle row 34A and the second nozzle row 34B, or it may be divided into three or more nozzle rows.

[0030] Inside the coating head 31 described above, a flow path for supplying paint (not shown) is provided. Additionally, inside the coating head 31, a nozzle pressurization chamber (not shown) is provided. On one wall of this nozzle pressurization chamber, a piezoelectric substrate 35 (see reference) is disposed for causing a volume change in the nozzle pressurization chamber, thereby extruding paint from the nozzle 33. Figure 5 Therefore, by applying a voltage to the piezoelectric substrate 35 from the outside, the piezoelectric substrate 35 expands and contracts, causing a change in the volume of the nozzle pressure chamber, thereby enabling the coating to be ejected from the nozzle 33.

[0031] It should be noted that the painting head 31 is not limited to Figure 3 The structure shown. For example, as Figure 4 As shown, a nozzle array 34 can also be formed by arranging multiple nozzles 33 along the short side direction (width direction; Y direction) of the coating head 31. Additionally, in use... Figure 4 When painting a vehicle with the paint head 31 as shown, the painting can be performed with the long side of the paint head 31 slightly tilted relative to the main scanning direction of the paint head 31.

[0032] For example, if in Figure 3 In the structure of the coating head 31 shown, the nozzle array 34 is inclined at an angle α relative to the main scanning direction. Therefore, as long as... Figure 4 The long side of the coating head 31 can be tilted at an angle α relative to the main scanning direction of the coating head 31. With this tilt, by simply adjusting the timing of paint ejection from each nozzle 33, it is possible to achieve [the desired effect]. Figure 3 The coating head 31 shown is coated in the same way.

[0033] Figure 5 This is a diagram showing a schematic structure for supplying paint to each nozzle 33 of the coating head 31. Figure 5 As shown, the coating head 31 has an internal flow path 36. The internal flow path 36 is a flow path that supplies paint to the nozzle pressurization chamber 37 via the paint supply path described later. It should be noted that... Figure 5 The diagram shows an internal flow path 36. However, since a number of nozzles 33 are formed in the coating head 31, a number of internal flow paths 36 are provided in the coating head 31.

[0034] Furthermore, the number of nozzle pressurization chambers 37 corresponds to the number of nozzles 33, and by driving the piezoelectric substrate 35, the paint inside the nozzles 33 can be ejected. Additionally, the nozzle pressurization chambers 37 are connected to the return flow path described later within the coating head 31 via an internal flow path such as a nozzle discharge flow path (not shown). Therefore, paint that is not ejected from the nozzles 33 returns to the return flow path.

[0035] With this structure, the paint supplied from the paint supply path (described later) is ejected from the nozzle 33 via the internal flow path 36 and the nozzle pressurization chamber 37. Additionally, paint not ejected from the nozzle 33 returns from the nozzle pressurization chamber 37 to the return flow path (described later) via an internal flow path (not shown).

[0036] (1-4. Regarding paint supply and cleaning facilities 50) Next, the paint supply and cleaning mechanism 50 will be described. For example... Figure 2 As shown, the paint supply and cleaning mechanism 50 includes a paint circulation path 51, a paint tank 57, a removal filter 58, a degassing module 59, a supply pump 61, a suction pump 62, a cleaning tank 63, a delivery pump 64, a drain tank 65, a compressor 66, a cleaning switching valve 67, three-way valves 71-74 (number 1-4), switching valves 81-86 (number 1-6), a first vacuum ejector 91, a second vacuum ejector 92, a cover 93, a cover moving mechanism 94, and other pipelines.

[0037] The paint circulation path 51 is a flow path for circulating paint, and includes a paint supply path 52, a return flow path 53, a bypass flow path 54, an external supply path 55, and a second bypass flow path 56. The paint supply path 52 is a flow path for supplying paint supplied from the external supply path 55 or returned from the return flow path 53 toward the coating head 31, and is connected to the internal flow path 36 within the coating head 31.

[0038] Here, each component of the paint supply and cleaning mechanism 50, including the paint circulation path 51 mentioned above, can also be supplied with cleaning fluid in addition to paint, but it will be described below only as supplied with "paint".

[0039] The return flow path 53 is connected to an internal flow path (not shown) within the coating head 31 and is used to return paint that has not been sprayed out by the coating head 31 to the paint tank 57.

[0040] In addition, the bypass flow path 54 is a flow path that connects the paint supply path 52 and the return flow path 53. That is, the bypass flow path 54 is set in parallel with the coating head 31, and when paint is not sprayed from the coating head 31, the paint flows in the bypass flow path 54 by switching the operation of the second three-way valve 72 and the third three-way valve 73, which will be described later.

[0041] External supply line 55 is a pipeline used to supply paint from the paint storage area, such as the circulation tank, to the paint tank 57.

[0042] The second bypass flow path 56 is a flow path connecting the first switching valve 81 and the sixth switching valve 86, and is used to form a circulation path including the paint tank 57 and to perform cleaning within the circulation path.

[0043] The paint tank 57 is a portion used to temporarily store paint supplied from the external supply path 55. Furthermore, the paint tank 57 may also have a function for removing air bubbles contained in the paint. The paint tank 57 is located in a stable position, such as outside the robotic arm R1, where its posture will not change. Additionally, the paint tank 57 is connected to the paint supply path 52 in a manner capable of supplying paint, and is connected to the return flow path 53 in a manner that allows paint to be supplied from the return flow path 53.

[0044] The removal filter 58 removes foreign matter contained in the paint flowing in the paint supply path 52. By precisely removing coarse foreign matter and pigment agglomerates from paint containing, for example, pigments, the removal filter 58 ensures the normal and continuous operation of the coating head 31. Furthermore, the removal filter 58 is disposed between the second switching valve 82 and the third switching valve 83 in the paint supply path 52.

[0045] The degassing module 59 is located downstream of the paint supply path 52, above the aforementioned removal filter 58, and is a component used to remove dissolved gases (degassing) from the paint. Furthermore, the degassing module 59 is positioned between the third switching valve 83 and the fourth switching valve 84 in the paint supply path 52.

[0046] The supply pump 61 is a mechanism for applying positive pressure to the paint flowing in the paint supply path 52 toward a position downstream of the supply pump 61.

[0047] It should be noted that, as the supply pump 61, a gear pump that can control the amount of paint supplied by controlling the rotation speed is preferably used. In this case, by reversing the supply pump 61, which is a gear pump, the paint and cleaning fluid can be reversed. However, a pump other than a gear pump can also be used as the supply pump 61.

[0048] The suction pump 62 is a mechanism that applies negative pressure to the paint flowing in the return flow path 53 at a position upstream of the suction pump 62.

[0049] As the suction pump 62, similar to the supply pump 61 described above, a gear pump capable of controlling the amount of paint supplied by controlling the rotational speed is preferably used. In this case, by reversing the suction pump 62, which is a gear pump, the paint and cleaning fluid can be reversed. However, a pump other than a gear pump can also be used as the suction pump 62.

[0050] The cleaning tank 63 is a section that stores cleaning fluid and supplies it for use during the cleaning of various parts of the paint supply and cleaning mechanism 50 and the painting head 31. The delivery pump 64 is a section that introduces the cleaning fluid stored in the cleaning tank 63 and delivers the introduced cleaning fluid to the cleaning switching valve 67. It should be noted that the delivery pump 64 corresponds to the pressurization mechanism, and depending on the switching of the fourth switching valve 84 and the fifth switching valve 85, it corresponds to either the first pressurization mechanism or the second pressurization mechanism.

[0051] In addition, the drain tank 65 is a part used to collect the cleaning fluid (drainage) discharged after cleaning of various parts of the paint supply and cleaning mechanism 50 and the painting head 31.

[0052] The compressor 66 is the part that supplies cleaning air to the cleaning switching valve 67. Furthermore, the cleaning switching valve 67 includes multiple valve sections, such as valve section 67a connected to a flow path extending from the cleaning tank 63, valve section 67b connected to a flow path extending from the compressor 66, and valve section 67c connected to a flow path extending to each of the switching valves 81-86 (described later). These multiple valve sections are individually opened and closed by the cleaning control unit 150 (described later). Through this opening and closing control, cleaning fluid from the cleaning tank 63 and air from the compressor 66 are alternately supplied to the paint supply path 52 or the return flow path 53 in the paint circulation path 51.

[0053] Additionally, a first three-way valve 71 is disposed between the paint tank 57 and the first switching valve 81 in the paint supply path 52, and is also connected to a branch path (not shown in the attached drawings) leading to the drain trough 65. This first three-way valve 71 can cut off the flow of paint or cleaning fluid between (a) the paint tank 57 side, (b) the first switching valve 81 side, and (c) the drain trough 65 side. Therefore, paint or cleaning fluid can flow in the remaining two uncut flow paths (the same applies to the second to fourth three-way valves 72 to 74 described below).

[0054] Similarly, the second three-way valve 72 is disposed between the fourth switching valve 84 and the coating head 31, and is also connected to one end of the bypass flow path 54. The second three-way valve 72 is capable of cutting off the flow of paint or cleaning fluid between (a) the side of the fourth switching valve 84, (b) the side of the coating head 31, and (c) the side of the bypass flow path 54.

[0055] Additionally, a third three-way valve 73 is disposed between the coating head 31 and the fifth switching valve 85, and is also connected to the other end of the bypass flow path 54. This third three-way valve 73 is capable of cutting off the flow of paint or cleaning fluid between any one of (a) the coating head 31 side, (b) the fifth switching valve 85 side, and (c) the bypass flow path 54 side.

[0056] Additionally, a fourth three-way valve 74 is positioned between the sixth switching valve 86 and the paint tank 57, and is also connected to a branch line (notation omitted) leading to the drain trough 65. This fourth three-way valve 74 is capable of cutting off the flow of paint or cleaning fluid between (a) the side of the sixth switching valve 86, (b) the side of the paint tank 57, and (c) the side of the drain trough 65.

[0057] Additionally, a first switching valve 81 is positioned between the first three-way valve 71 and the second switching valve 82 in the paint supply path 52. This first switching valve 81 has four valve sections 81a-81d, which can switch the flow paths of liquid (paint, cleaning fluid) and air (air used during cleaning) depending on the opening and closing states of these valve sections 81a-81d. Specifically, valve section 81a is connected to the upstream side of the paint supply path 52, and valve section 81b is connected to the downstream side of the paint supply path 52. Furthermore, valve section 81c is connected to a cleaning switching valve 67 that can be switched relative to the cleaning tank 63 or the compressor 66. Additionally, valve section 81d is connected to the second bypass flow path 56.

[0058] Therefore, when paint is supplied from paint tank 57 to coating head 31, or during paint circulation, valves 81a and 81b are opened, and paint from paint tank 57 flows downstream of paint supply path 52. Furthermore, during cleaning, if either valve 81a or valve 81b, or valve 81c, is opened, cleaning fluid supplied from cleaning tank 63 or air supplied from compressor 66 flows through the opened valve into the flow path connected to that valve. It should be noted that in the following description, a fluid containing at least one of the cleaning fluid and air used during cleaning will be described as the cleaning fluid.

[0059] Furthermore, valve section 81d is connected to valve section 86d of the sixth switching valve 86 (described later) disposed on return flow path 53 via the second bypass flow path 56. Therefore, by opening valve section 81a and valve section 81d, for example, a circulation path is formed connecting the upstream side of paint supply path 52 (the side connected to paint tank 57), the second bypass flow path 56, and the downstream side of return flow path 53 (the side connected to paint tank 57).

[0060] Furthermore, the second switching valve 82 is connected to a position in the paint supply path 52 that is downstream of the first switching valve 81 and upstream of the removal filter 58. Like the first switching valve 81, the second switching valve 82 has four valve sections 82a-82d, which can switch the flow paths of liquid (paint, cleaning fluid) and gas (air used during cleaning) depending on the opening and closing states of these valve sections 82a-82d. Specifically, valve section 82a is connected to the upstream side of the paint supply path 52, and valve section 82b is connected to the downstream side of the paint supply path 52. Additionally, valve section 82c is connected to a cleaning switching valve 67 that can be switched relative to the cleaning tank 63 or the compressor 66. Furthermore, valve section 82d is connected to the drain tank 65 side.

[0061] Therefore, when paint is supplied from paint tank 57 to coating head 31, or during paint circulation, valves 82a and 82b are opened, and paint from paint tank 57 flows downstream of paint supply path 52. Furthermore, during cleaning, if either valve 82a or valve 82b, or valve 82c, is opened, cleaning fluid flows through the opened valve into the flow path connected to that valve.

[0062] Furthermore, the third switching valve 83 is connected to a position in the paint supply path 52 that is downstream of the second switching valve 82 and the removal filter 58 and upstream of the degassing module 59. Like the first switching valve 81 described above, the third switching valve 83 has four valve sections 83a-83d, which can switch the flow paths of liquid (paint, cleaning fluid) and gas (air used during cleaning) depending on the opening and closing states of these valve sections 83a-83d. Specifically, valve section 83a is connected to the upstream side of the paint supply path 52, and valve section 83b is connected to the downstream side of the paint supply path 52. Additionally, valve section 83c is connected to a cleaning switching valve 67 that can be switched relative to the cleaning tank 63 or the compressor 66. Furthermore, valve section 83d is connected to the drain tank 65 side.

[0063] Therefore, when paint is supplied from paint tank 57 to coating head 31, or during paint circulation, valves 83a and 83b are opened, and paint from paint tank 57 flows downstream of paint supply path 52. Furthermore, during cleaning, if either valve 83a or valve 83b, as well as valve 83c, are opened, cleaning fluid flows through the opened valve into the flow path connected to that valve.

[0064] Furthermore, the fourth switching valve 84 is connected to the paint supply line 52 at a position downstream of the third switching valve 83 and the degassing module 59 and upstream of the second three-way valve 72. This fourth switching valve 84 differs from the first switching valve 81 described above; it has six valve sections 84a to 84f, and can switch the flow paths of liquid (paint, cleaning fluid) and gas (air used during cleaning) according to the opening and closing states of these valve sections 84a to 84f.

[0065] Specifically, valve 84a is connected to the upstream side of paint supply passage 52, and valve 84b is connected to the downstream side of paint supply passage 52. Therefore, when valves 84a and 84b are opened, paint from the upstream side of paint supply passage 52 flows to the second three-way valve 72 on the downstream side of paint supply passage 52. Furthermore, valve 84a is also connected to valve 84f independently of valves 84b, 84c, and 84e. Therefore, when valves 84c or 84e and valve 84b are opened, allowing cleaning fluid, air, or paint to flow through these valves, valve 84a can be connected to valve 84f independently of this flow.

[0066] Furthermore, valve 84c is connected to a cleaning switching valve 67 that can be switched relative to the cleaning tank 63 or the compressor 66. Therefore, during cleaning, if valve 84a or valve 84b and valve 84c are opened, the cleaning fluid flows through the opened valve to the flow path connected to that valve.

[0067] Furthermore, valve section 84d is connected independently to the cleaning switching valve 67, separate from valve section 84c. The flow path of valve section 84d is not connected to valve sections 84b, 84c, or 84e, but only to valve sections 84a and 84f. For example, if valve sections 84d and 84f are opened, the cleaning fluid flows to the drain tank 65 via the opened valve section 84f.

[0068] Furthermore, valve 84e is connected to drain tank 65 via the first vacuum ejector 91, which will be described later. Therefore, if the first vacuum ejector 91 is operated while either valve 84a or valve 84b is open and valve 84e is open, the cleaning fluid that has been cleaned is discharged into drain tank 65 via valve 84e and vacuum ejector 91.

[0069] Additionally, valve 84f is also connected to the drain trough 65. The flow path of valve 84f is not connected to valves 84b, 84c, and 84e, but to valves 84a and 84d. If valves 84a and 84f are opened, the paint drain from the upstream side of the paint supply path 52 flows to the drain trough 65 via valves 84a and 84f.

[0070] Furthermore, the fifth switching valve 85 is connected to the return flow path 53 at a position downstream of the third three-way valve 73 and upstream of the suction pump 62. Like the fourth switching valve 84 described above, the fifth switching valve 85 has six valve sections 85a to 85f, which allow switching of the flow paths for liquids (coatings, cleaning fluids) and air based on the opening and closing states of these valve sections 85a to 85f.

[0071] Specifically, valve 85a is connected to the upstream side of the return flow path 53, and valve 85b is connected to the downstream side of the return flow path 53. Therefore, when valves 85a and 85b are opened, the paint from the upstream side of the return flow path 53 flows towards the suction pump 62 on the downstream side of the return flow path 53. Furthermore, valve 85b is also connected to valve 85f independently of valves 85a, 85c, and 85e. Therefore, when valves 85c or 85e and valve 85b are opened and cleaning fluid or paint flows through these valves, valve 85b can be connected to valve 85f independently of this flow.

[0072] In addition, valve 85c is connected to cleaning switching valve 67. Therefore, if either valve 85a or valve 85b, or valve 85c, is opened during cleaning, the cleaning fluid flows through the opened valve into the flow path connected to that valve.

[0073] Furthermore, valve section 85d is connected to the cleaning switching valve 67 independently of valve section 85c described above. The flow path of valve section 85d is not connected to valve sections 85a, 85c, or 85e, but only to valve sections 85b and 85f. For example, if valve sections 85d and 85f are opened, the cleaning fluid flows to the drain tank 65 through the opened valve section 85f.

[0074] Furthermore, valve 85e is connected to drain tank 65 via the second vacuum ejector 92, which will be described later. Therefore, if the second vacuum ejector 92 is operated while either valve 85a or valve 85b is open and valve 85e is open, the cleaning fluid that has been cleaned will be discharged into drain tank 65 via valve 85e and the second vacuum ejector 92.

[0075] Additionally, valve 85f is connected to valves 85b and 85d and the drain trough 65. The flow path of valve 85f is not connected to valves 85a, 85c, and 85e, but is connected to valves 85b and 85d. If valves 85b and 85f are opened, the paint drain returning to the downstream side of flow path 53 flows through valves 85b and 85f to the drain trough 65.

[0076] Additionally, a sixth switching valve 86 is disposed between the suction pump 62 and the fourth three-way valve 74 in the return flow path 53. This sixth switching valve 86 has four valve sections 86a-86d, which can switch the flow paths of liquids (coatings, cleaning fluids) and air depending on the opening and closing states of these valve sections 86a-86d. Specifically, valve section 86a is connected to the upstream side of the return flow path 53, and valve section 86b is connected to the downstream side of the return flow path 53. Furthermore, valve section 86c is connected to a cleaning switching valve 67 that can be switched relative to the cleaning tank 63 or the compressor 66. Additionally, valve section 86d is connected to the second bypass flow path 56.

[0077] Therefore, when paint is supplied from paint tank 57 to coating head 31, or during paint circulation, valves 86a and 86b are opened, and paint from the coating head 31 side (upstream side) flows downstream of the return flow path 53. Furthermore, during cleaning, if either valve 86a or valve 86b, or valve 86c, is opened, cleaning fluid flows through the opened valve into the flow path connected to that valve.

[0078] Furthermore, as described above, valve section 86d is connected to valve section 81d of the first switching valve 81 via the second bypass flow path 56. Therefore, if valve sections 81a and 81d of the first switching valve 81 are open, and valve sections 86d and 86b of the sixth switching valve 86 are open, the second bypass flow path 56 connecting valve sections 81d and 86d is opened. This forms a circulation path in which the paint circulates in the paint tank 57, the first switching valve 81, the second bypass flow path 56, and the sixth switching valve 86 in that order.

[0079] Furthermore, the first vacuum ejector 91 is positioned midway in the pipeline connecting the aforementioned valve section 84e to the drain tank 65. The first vacuum ejector 91 is a device that discharges fluid by generating a vacuum. When the first vacuum ejector 91 is in operation, with valve sections 84b and 84e open, paint or cleaning fluid can be discharged from the coating head 31 side at a predetermined pressure.

[0080] Furthermore, the second vacuum ejector 92 is positioned midway in the pipeline connecting the aforementioned valve section 85e to the drain tank 65. Like the first vacuum ejector 91, the second vacuum ejector 92 is a device that discharges fluid by generating a vacuum. When the second vacuum ejector 92 is in operation, with valve sections 85a and 85e open, paint or cleaning fluid can be discharged from the coating head 31 side at a predetermined pressure.

[0081] Furthermore, the first vacuum ejector 91 and the second vacuum ejector 92 are configured to have a suction force sufficiently higher than that of the suction pump 62. In detail, the operation of the first vacuum ejector 91 and the second vacuum ejector 92 is controlled by the cleaning control unit 150 such that the negative pressure during suction based on the first vacuum ejector 91 and the second vacuum ejector 92 is greater than the negative pressure during suction based on the suction pump 62. However, the negative pressure during suction based on the first vacuum ejector 91 and the second vacuum ejector 92 can also be at or below the same level as the negative pressure during suction based on the suction pump 62.

[0082] It should be noted that at least one of the first vacuum ejector 91 and the second vacuum ejector 92 corresponds to the suction mechanism. Additionally, either the first vacuum ejector 91 or the second vacuum ejector 92 corresponds to the first suction mechanism, and the other of the first vacuum ejector 91 and the second vacuum ejector 92 corresponds to the second suction mechanism.

[0083] The cap 93 is a component that seals the nozzle forming surface 32, which exposes the nozzle 33, by abutting against it in a tight-fitting state. The cap 93 is preferably made of a flexible and deformable material, such as rubber. Alternatively, the cap 93 may have a structure that forms several spaces (internal spaces) between itself and the nozzle forming surface 32, into which paint droplets can be discharged. In this case, it is preferable that the peripheral wall forming the internal space of the cap 93 does not directly abut against the portion of the nozzle forming surface 32 where the nozzle 33 is formed. Furthermore, it is preferable to connect a discharge pipe for discharging paint droplets to the cap 93.

[0084] Additionally, the cap moving mechanism 94 is a mechanism for moving the cap 93 to seal or release the nozzle forming surface 32. This cap moving mechanism 94 can be a separate mechanism having a drive source such as a motor or actuator and a transmission mechanism such as a cam or gear that transmits the driving force from the drive source. However, regarding the cap moving mechanism 94, the robot arm R1 capable of moving the coating head 31 (coating head unit 30) relative to the cap 93 can also be designated as the cap moving mechanism 94.

[0085] (1-5. Regarding the control unit 100) Next, a general structure of the control unit 100 used to control the operation of the cleaning system 1 of the painting robot 10 will be described. Figure 6 This is a diagram showing a schematic structure of the control system centered on the control unit 100 of the cleaning system 1 of the painting robot 10. As shown... Figure 6 As shown, the control unit 100 includes a main control unit 110, a robot arm control unit 120, a head control unit 130, a paint supply control unit 140, and a cleaning control unit 150. It should be noted that at least one of the control unit 100, the main control unit 110, and the cleaning control unit 150 corresponds to a control mechanism.

[0086] When performing coating, the main control unit 110 in the above-mentioned control structure sends a specified control signal to the robot arm control unit 120, head control unit 130 and paint supply control unit 140 as needed, so that each motor of the robot arm R1, each working part of the paint supply and cleaning mechanism 50 and the piezoelectric substrate 35 cooperate to perform coating on the object to be coated.

[0087] When performing cleaning, the main control unit 110 sends specified control signals to the robot arm control unit 120, head control unit 130, paint supply control unit 140 and cleaning control unit 150 as needed, so that each motor of the robot arm R1, each working part of the paint supply and cleaning mechanism 50 and the piezoelectric substrate 35 cooperate to perform cleaning on the object to be coated.

[0088] The robot arm control unit 120 is the part that controls the drive of each motor of the robot arm R1.

[0089] The head control unit 130 controls the operation of the piezoelectric substrate 35 within the coating head unit 30 based on image processing in an image processing device (not shown). Additionally, the head control unit 130 can also control the operation of the piezoelectric substrate 35 during cleaning within the coating head 31, as needed.

[0090] The paint supply control unit 140 is a part that controls the supply of paint to the coating head 31. Specifically, it controls the operation of each working part of the paint supply and cleaning mechanism 50, such as the supply pump 61, the suction pump 62, the first to fourth three-way valves 71 to 74, and the first to sixth switching valves 81 to 86.

[0091] The cleaning control unit 150 controls the operation of related working parts when cleaning the components within the internal flow path 36 and paint circulation path 51 of the coating head 31 using a cleaning fluid (cleaning liquid or air). Specifically, the cleaning control unit 150 controls the operation of various working parts in the paint supply and cleaning mechanism 50, including the supply pump 61, suction pump 62, delivery pump 64, compressor 66, cleaning switching valve 67, first to fourth three-way valves 71 to 74, first to sixth switching valves 81 to 86, first vacuum ejector 91, second vacuum ejector 92, and cap moving mechanism 94.

[0092] (2. Controls during cleaning) Next, the control details during cleaning of the internal flow path 36 within the coating head 31 will be explained. (2-1. About forward cleaning) First, let's explain forward cleaning. Figure 7 This is a diagram showing the cleaning process during the cleaning of the internal flow path 36 within the coating head 31. In this forward cleaning, similar to normal coating, cleaning fluid such as cleaning liquid or air is supplied from the paint supply path 52 towards the coating head 31. In this case, based on the command of the main control unit 110, the cleaning control unit 150 switches the cleaning switching valve 67, opening valve 67b and closing valve 67a. Furthermore, the cleaning control unit 150 operates the second three-way valve 72 to cut off the flow of cleaning fluid to the bypass flow path 54, and operates the third three-way valve 73 to cut off the supply of cleaning fluid from the bypass flow path 54.

[0093] Additionally, the cleaning control unit 150 activates the compressor 66, preparing it to supply cleaning air to the valve unit 67c. Furthermore, in addition to the above, the cleaning control unit 150 activates the cover moving mechanism 94, causing the cover 93 to seal tightly against the nozzle forming surface 32. This seals the nozzle forming surface 32 (nozzle 33) from the outside.

[0094] Subsequently, the cleaning control unit 150 switches the fourth switching valve 84, opening valves 84b and 84c while closing the other valves 84a, 84d, 84e, and 84f. Furthermore, the cleaning control unit 150 switches the fifth switching valve 85, opening valves 85a and 85e while closing the other valves 85b, 85c, 85d, and 85f.

[0095] Then, the cleaning air flows through valves 67b, 67c and 84b, 84c for a predetermined time (e.g., 0.5 seconds). Figure 7 (a) The air supply is ON. Then, either valve 84b or valve 84c is cut off, thereby cutting off the air supply. Figure 7 (a) Air supply OFF). Then, preferably, valve 84e is opened to release air, thereby regulating the pressure. Figure 7 (a) Release ON). At this time, the air pressure is preferably set to 0.3 to 0.4 bar. However, it may also be set to a pressure outside this range. In particular, when using the coating head 31 to achieve high pressure resistance, it is preferable to set it to a pressure range higher than that described above.

[0096] Next, the cleaning control unit 150 operates the delivery pump 64, preparing it to supply cleaning fluid. Then, the cleaning control unit 150 is set to open valves 84b and 84c while closing other valves 84a, 84d, 84e, and 84f, and switches the cleaning switching valve 67 so that valve 67a is open while valve 67b is closed.

[0097] Then, the cleaning fluid flows through valve sections 67a, 67c and 84b, 84c for a predetermined time (e.g., 15 seconds). Figure 7 (a) The supply of cleaning fluid is ON. Then, either valve 84b or valve 84c is cut off, thereby cutting off the supply of the cleaning fluid. Figure 7 (a) The cleaning fluid supply is OFF. Thus, the cleaning fluid is supplied to the internal flow path 36 of the coating head 31 via the paint supply path 52. At this time, the pressure of the cleaning fluid is preferably set to 0.3 to 0.4 bar. However, it may also be set to a pressure outside this range. In particular, when using a coating head 31 that achieves high pressure resistance, it is preferable to set it to a pressure range higher than that described above.

[0098] Then, the air or cleaning fluid that has cleaned the internal flow path 36 is discharged into the drain tank 65 via the return flow path 53 and valve sections 85a and 85e. During this discharge, the cleaning control unit 150 activates the second vacuum ejector 92, using negative pressure to discharge the cleaned cleaning fluid or air into the drain tank 65. This increases the amount of cleaning fluid or air introduced into the internal flow path 36.

[0099] Therefore, air and cleaning fluid at a specified pressure are alternately supplied to the internal flow path 36 via the paint supply path 52 at a specified pressure. This performs forward cleaning of the internal flow path 36. At this time, since the nozzle forming surface 32 (nozzle 33) is sealed by the cover 93, the internal flow path 36 can be pressurized, and cleaning can be performed under this pressurized state.

[0100] Furthermore, by operating the second vacuum ejector 92, even if the return flow path 53 and the paint supply path 52 become longer, the discharge performance of the cleaning fluid after cleaning can be improved compared to the case where the cleaning fluid is discharged solely by operating the delivery pump 64.

[0101] In particular, when the cleaning fluid is discharged via the valve section 85e of the fifth switching valve 85, since it is not discharged via the suction pump 62, in the comparative example of the structure that does not use the second vacuum ejector 92, the drive unit for discharging the cleaning fluid is only the delivery pump 64, and the discharge performance of the cleaning fluid is often reduced.

[0102] However, as described above, by providing a second vacuum ejector 92, the cleaning fluid after cleaning is discharged in addition to the operation of the delivery pump 64. Therefore, compared to the case where only the delivery pump 64 is operated, the discharge performance of the cleaning fluid after cleaning can be improved. That is, in forward cleaning, even if the return flow path 53 and the paint supply path 52 become longer, the decrease in the cleaning effectiveness of the paint circulation path 51 and the increase in cleaning time can be suppressed.

[0103] Furthermore, if the forward cleaning of the internal flow path 36 based on air and cleaning fluid as described above is set as a cycle, it is preferable to repeat the cleaning cycle more than twice.

[0104] (2-2. About reverse cleaning) Next, reverse cleaning will be described. In this reverse cleaning, cleaning fluids such as cleaning liquid and air are supplied to the coating head 31 in the opposite direction to the forward cleaning described above. In this case, based on the command of the main control unit 110, the cleaning control unit 150 switches the cleaning switching valve 67, opening valve 67b and closing valve 67a. In addition, the cleaning control unit 150 operates the second three-way valve 72 to cut off the flow of cleaning fluid to the bypass flow path 54, and operates the third three-way valve 73 to cut off the supply of cleaning fluid from the bypass flow path 54.

[0105] Additionally, the cleaning control unit 150 activates the compressor 66, preparing it to supply cleaning air to the valve unit 67c. Furthermore, in addition to the above, the cleaning control unit 150 activates the cover moving mechanism 94, causing the cover 93 to seal tightly against the nozzle forming surface 32. This seals the nozzle forming surface 32 (nozzle 33) from the outside.

[0106] Subsequently, the cleaning control unit 150 switches the fifth switching valve 85, opening valves 85a and 85c while closing the other valves 85b, 85d, 85e, and 85f. Furthermore, the cleaning control unit 150 switches the fourth switching valve 84, opening valves 84b and 84e while closing the other valves 84a, 84c, 84d, and 84f.

[0107] Then, the cleaning air flows through valves 67b, 67c and 85a, 85c for a predetermined time (e.g., 0.5 seconds). Figure 7 (b) The air supply is ON). Then, either valve 85a or valve 85c is cut off, thereby cutting off the air supply. Figure 7 (b) Air supply OFF). Then, preferably, valve 85e is opened to release air, thereby regulating the pressure. Figure 7 (b) of the release of ON).

[0108] Next, the cleaning control unit 150 operates the delivery pump 64, preparing it to supply cleaning fluid. Then, with valves 85a and 85c open and other valves 85b, 85d, 85e, and 85f closed, the cleaning control unit 150 switches the cleaning switching valve 67, opening valve 67a and closing valve 67b.

[0109] Then, the cleaning fluid flows through valve sections 67a, 67c and 85a, 85c for a predetermined time (e.g., 15 seconds). Figure 7 (b) The supply of cleaning fluid is ON). Then, either valve 85a or valve 85c is cut off, thereby cutting off the supply of the cleaning fluid. Figure 7 (b) The cleaning fluid supply is OFF). Thus, the cleaning fluid is supplied to the internal flow path 36 of the coating head 31 via the paint supply path 52.

[0110] Then, the air or cleaning fluid that has cleaned the internal flow path 36 is discharged into the drain tank 65 via the paint supply path 52 and valve sections 84b and 84e. During this discharge, the cleaning control unit 150 activates the first vacuum ejector 91, using negative pressure to discharge the cleaned cleaning fluid or air into the drain tank 65. This increases the amount of cleaning fluid or air introduced into the internal flow path 36.

[0111] Therefore, air and cleaning fluid at a specified pressure are alternately supplied to the internal flow path 36 via the return flow path 53 at a specified pressure. This performs reverse cleaning of the internal flow path 36. At this time, since the nozzle forming surface 32 (nozzle 33) is sealed by the cover 93, the internal flow path 36 can be pressurized, and cleaning can be performed under this pressurized state.

[0112] Furthermore, as described above, in addition to the operation of the delivery pump 64, the cleaning fluid after cleaning is discharged through the operation of the first vacuum ejector 91. Therefore, compared to the case where only the delivery pump 64 is operated, the discharge performance of the cleaning fluid after cleaning can be improved. That is, in reverse cleaning, even if the return flow path 53 and the paint supply path 52 become longer, the decrease in the cleaning effectiveness of the paint circulation path 51 and the increase in cleaning time can be suppressed.

[0113] Furthermore, if the reverse cleaning of the internal flow path 36 based on air and cleaning fluid as described above is set as a cycle, it is preferable to repeat the cleaning cycle more than twice.

[0114] (3. Variations) (3-1. Cleaning when there is only one vacuum ejector) In the above embodiment, two vacuum ejectors, a first vacuum ejector 91 and a second vacuum ejector 92, are used as vacuum ejectors. However, it is also possible to use a single vacuum ejector for both forward and reverse cleaning. In this case, cleaning can be performed on each section designated as the cleaning target. The following is based on... Figure 8 This situation needs clarification. It should be noted that... Figure 8 In this description, a vacuum ejector 95 will be used as an example. In this case, the vacuum ejector 95 corresponds to the cleaning suction mechanism, and also to either the first or second cleaning suction mechanism. However, the first to sixth switching valves 81 to 86 may also include a cleaning suction mechanism, or either the first or second cleaning suction mechanism.

[0115] (3-1a. On forward cleaning) First, the forward cleaning process will be explained. In this case, the cleaning target is the first zone, which includes the internal flow path 36 of the coating head 31, the paint supply path 52 leading to the internal flow path 36, and the return flow path 53 for the cleaning fluid discharged from the internal flow path 36. First, the cleaning control unit 150, as in the embodiment described above, controls the operation of the first to third three-way valves 71 to 73, the compressor 66, the cleaning switching valve 67, and the cover moving mechanism 94. Then, the fourth switching valve 84 is switched, opening valve sections 84b and 84c while closing the other valve sections 84a, 84d, 84e, and 84f. Furthermore, the cleaning control unit 150 switches the fifth switching valve 85, opening valve sections 85a and 85e while closing the other valve sections 85b, 85c, 85d, and 85f.

[0116] Furthermore, the details of the subsequent cleaning are the same as those in "2-1. Regarding forward cleaning" above, so the details of that process are omitted.

[0117] Then, the air or cleaning fluid that has cleaned the internal flow path 36 is discharged into the drain tank 65 via the return flow path 53 and valve sections 85a and 85e. During this discharge, the cleaning control unit 150 activates the vacuum ejector 95, using negative pressure to discharge the cleaned cleaning fluid or air into the drain tank 65. As a result, compared to the case where the suction pump 62 is activated, the amount of cleaning fluid or air introduced into the internal flow path 36 can be increased.

[0118] Here, the cleaning control unit 150 may, for example, operate the cover moving mechanism 94 to adjust the tight contact state of the cover 93 relative to the nozzle forming surface 32, and control the operation of the vacuum ejector 95 so that the negative pressure change generated by the operation of the vacuum ejector 95 can make the ratio of the amount of cleaning fluid flowing in the internal flow path 36 ejected from the nozzle 33 to the amount that does not eject from the nozzle 33 but passes through the internal flow path 36 variable.

[0119] That is, when the cover 93 is not completely sealed to the nozzle forming surface 32, the cleaning fluid will leak from the nozzle 33 to a predetermined extent. If the negative pressure change caused by the operation of the vacuum ejector 95 during this leakage state is adjusted, the amount of cleaning fluid leaking from the nozzle 33 can be adjusted to an appropriate proportion. Therefore, even if it is better to directly remove foreign matter from the nozzle 33 through the cleaning fluid, this can also be addressed by adjusting the amount of cleaning fluid ejected from the nozzle 33.

[0120] As described above, air and cleaning fluid at a specified pressure are alternately supplied to the internal flow path 36 via the paint supply path 52 at a specified pressure. This performs forward cleaning of the internal flow path 36. At this time, since the nozzle forming surface 32 (nozzle 33) is sealed by the cover 93, the internal flow path 36 can be pressurized, and cleaning can be performed under this pressurized state.

[0121] Furthermore, by operating the vacuum ejector 95, even if the return flow path 53 and the paint supply path 52 become longer, the discharge performance of the cleaning fluid after cleaning can be improved compared to the case where the cleaning fluid is discharged solely by operating the delivery pump 64.

[0122] In particular, when the cleaning fluid is discharged via the valve section 85e of the fifth switching valve 85, since it is not discharged via the suction pump 62, in the comparative example of the structure that does not use the vacuum ejector 95, the drive unit for discharging the cleaning fluid is only the delivery pump 64, and the discharge performance of the cleaning fluid is often reduced.

[0123] However, as described above, by installing the vacuum ejector 95, the cleaning fluid after cleaning is discharged in addition to the operation of the delivery pump 64. Therefore, compared to the case where only the delivery pump 64 is operated, the discharge performance of the cleaning fluid after cleaning can be improved. That is, in forward cleaning, even if the return flow path 53 and the paint supply path 52 become longer, the decrease in the cleaning effectiveness of the paint circulation path 51 and the increase in cleaning time can be suppressed.

[0124] Furthermore, if the forward cleaning of the internal flow path 36 based on air and cleaning fluid as described above is set as a cycle, it is preferable to repeat the cleaning cycle more than twice.

[0125] Furthermore, if the cleaning target is a second section that further includes the degassing module 59 within the first section of the internal flow path 36, as described above, the cleaning control unit 150 switches the third switching valve 83, opening valves 83b and 83c while closing the other valves 83a and 83d. Additionally, the cleaning control unit 150 switches the fourth switching valve 84, opening valves 84a and 84b while closing the other valves 84c, 84d, 84e, and 84f. Further, the cleaning control unit 150 switches the fifth switching valve 85, opening valves 85a and 85e while closing the other valves 85b, 85c, 85d, and 85f.

[0126] Furthermore, the details of the subsequent cleaning are the same as those of the first interval mentioned above, so details about them are omitted.

[0127] Furthermore, when the cleaning objective is a third section that further includes the removal filter 58 within the second section, which primarily targets the internal flow path 36 and the degassing module 59, as described above, the second switching valve 82 is switched, opening valve sections 82b and 82c while closing the other valve sections 82a and 82d. Additionally, the cleaning control unit 150 switches the third switching valve 83, opening valve sections 83a and 83b while closing the other valve sections 83c and 83d. Furthermore, the cleaning control unit 150 switches the fourth switching valve 84, opening valve sections 84a and 84b while closing the other valve sections 84c, 84d, 84e, and 84f. Moreover, the cleaning control unit 150 switches the fifth switching valve 85, opening valve sections 85a and 85e while closing the other valve sections 85b, 85c, 85d, and 85f.

[0128] Furthermore, the details of the subsequent cleaning are the same as those of the first interval mentioned above, so details about them are omitted.

[0129] Furthermore, when the cleaning target is a third section that further includes the paint supply path 52 between the first switching valve 81 and the second switching valve 82, where the main cleaning targets are the internal flow path 36, the degassing module 59, and the removal filter 58, as described above, the first switching valve 81 is switched so that valve sections 81b and 81c are opened, while the other valve sections 81a and 81d are closed. Additionally, the cleaning control unit 150 switches the second switching valve 82 so that valve sections 82a and 82b are opened, while the other valve sections 82c and 82d are closed. Furthermore, the cleaning control unit 150 switches the third switching valve 83 so that valve sections 83a and 83b are opened, while the other valve sections 83c and 83d are closed. Finally, the cleaning control unit 150 switches the fourth switching valve 84 so that valve sections 84a and 84b are opened, while the other valve sections 84c, 84d, 84e, and 84f are closed. Furthermore, the cleaning control unit 150 switches the fifth switching valve 85, opening valves 85a and 85e while closing the other valves 85b, 85c, 85d, and 85f.

[0130] Furthermore, the details of the subsequent cleaning are the same as those of the first interval mentioned above, so details about them are omitted.

[0131] (3-1b. On reverse cleaning) Next, the reverse cleaning will be described. In this reverse cleaning, cleaning fluids such as cleaning liquid and air are supplied to the coating head 31 in the opposite direction to the forward cleaning described above. In this case, the cleaning target is described as the first zone, which is the internal flow path 36 of the coating head 31, the paint supply path 52 leading to the internal flow path 36, and the return flow path 53 for the cleaning fluid discharged from the internal flow path 36. First, the cleaning control unit 150 controls the operation of the first to third three-way valves 71 to 73, the compressor 66, the cleaning switching valve 67, and the cap moving mechanism 94 in the same manner as in the embodiment described above. Then, the cleaning control unit 150 switches the fifth switching valve 85, opening valves 85a and 85c, while closing the other valves 85b, 85d, 85e, and 85f. Furthermore, the cleaning control unit 150 switches the fourth switching valve 84, opening valves 84b and 84e while closing the other valves 84a, 84c, 84d, and 84f.

[0132] Furthermore, the details of the subsequent cleaning are the same as those in "2-2. Regarding reverse cleaning" above, so the details of that process are omitted.

[0133] Then, the air or cleaning fluid that has cleaned the internal flow path 36 is discharged into the drain tank 65 via the paint supply path 52 and valve sections 84b and 84e. During this discharge, the cleaning control unit 150 activates the vacuum ejector 95, using negative pressure to discharge the cleaned cleaning fluid or air into the drain tank 65. This increases the amount of cleaning fluid or air introduced into the internal flow path 36.

[0134] Therefore, air and cleaning fluid at a specified pressure are alternately supplied to the internal flow path 36 via the return flow path 53 at a specified pressure. This performs reverse cleaning of the internal flow path 36. At this time, since the nozzle forming surface 32 (nozzle 33) is sealed by the cover 93, the internal flow path 36 can be pressurized, and cleaning can be performed under this pressurized state.

[0135] Furthermore, as described above, by providing a vacuum ejector 95, the cleaning fluid after cleaning is discharged in addition to the operation of the delivery pump 64. Therefore, compared to the case where only the delivery pump 64 is operated, the discharge performance of the cleaning fluid after cleaning can be improved. That is, in reverse cleaning, even if the return flow path 53 and the paint supply path 52 become longer, the decrease in the cleaning effectiveness of the paint circulation path 51 and the increase in cleaning time can be suppressed.

[0136] Furthermore, if the reverse cleaning of the internal flow path 36 based on air and cleaning fluid as described above is set as a cycle, it is preferable to repeat the cleaning cycle more than twice.

[0137] Furthermore, when reverse cleaning is performed in the second section, which further includes the degassing module 59, where the primary cleaning target is the first section of the internal flow path 36 as described above, the cleaning control unit 150, as described above, switches the fifth switching valve 85, opening valves 85a and 85c while closing the other valves 85b, 85d, 85e, and 85f. Additionally, the cleaning control unit 150 switches the fourth switching valve 84, opening valves 84a and 84b while closing the other valves 84c, 84d, 84e, and 84f. Moreover, the cleaning control unit 150 switches the third switching valve 83, opening valves 83b and 83d while closing the other valves 83a and 83c.

[0138] Furthermore, the details of the subsequent cleaning are the same as those of the first interval mentioned above, so details about them are omitted.

[0139] Furthermore, when reverse cleaning is performed in the third section, which further includes the removal filter 58, where the primary cleaning target is the internal flow path 36 and the degassing module 59, as described above, the cleaning control unit 150, as described above, switches the fifth switching valve 85, opening valves 85a and 85c while closing the other valves 85b, 85d, 85e, and 85f. Additionally, the cleaning control unit 150 switches the fourth switching valve 84, opening valves 84a and 84b while closing the other valves 84c, 84d, 84e, and 84f. Furthermore, the cleaning control unit 150 switches the third switching valve 83, opening valves 83a and 83b while closing the other valves 83c and 83d. Finally, the cleaning control unit 150 switches the second switching valve 82, opening valves 82b and 82d while closing the other valves 82a and 82c.

[0140] Furthermore, the details of the subsequent cleaning are the same as those of the first interval mentioned above, so details about them are omitted.

[0141] Furthermore, when reverse cleaning is performed in the third section, which includes the paint supply path 52 between the first switching valve 81 and the second switching valve 82, and further encompasses the internal flow path 36, the degassing module 59, and the removal filter 58 as described above, the cleaning control unit 150, as described above, switches the fifth switching valve 85, opening valves 85a and 85c while closing the other valves 85b, 85d, 85e, and 85f. Additionally, the cleaning control unit 150 switches the fourth switching valve 84, opening valves 84a and 84b while closing the other valves 84c, 84d, 84e, and 84f. Finally, the cleaning control unit 150 switches the third switching valve 83, opening valves 83a and 83b while closing the other valves 83c and 83d. Furthermore, the cleaning control unit 150 switches the second switching valve 82, opening valves 82a and 82b while closing the other valves 82c and 82d. Additionally, the cleaning control unit 150 switches the first switching valve 81, opening valves 81a and 81b while closing the other valves 81c and 81d. Moreover, the cleaning control unit 150 switches the first three-way valve 71 so that the cleaning fluid does not flow towards the paint tank 57, but instead flows towards the drain trough 65.

[0142] Furthermore, the details of the subsequent cleaning are the same as those of the first interval mentioned above, so details about them are omitted.

[0143] (3-2. Discharge of cleaning fluid after cleaning performed outside of the 5th switching valve 85) In the aforementioned forward cleaning, the cleaning fluid after cleaning is discharged from the valve portion 85e of the fifth switching valve 85 toward the drain tank 65. However, the cleaning fluid after cleaning may also be discharged toward the drain tank 65 after at least via the sixth switching valve 86.

[0144] In this case, the cleaning control unit 150 switches, for example, the fifth switching valve 85, opening valves 85a and 85b and closing other valves 85c, 85d, 85e, and 85f. Additionally, the cleaning control unit 150 switches the sixth switching valve 86, opening valves 86a and 86b and closing other valves 86c and 86d. Furthermore, the cleaning control unit 150 switches the fourth three-way valve 74 so that the cleaning fluid does not flow towards the paint tank 57, but flows towards the drain trough 65.

[0145] In this case, cleaning fluid can also flow in the return flow path 53 between the 5th switching valve 85 and the 6th switching valve 86 for cleaning. In addition, since the cleaning fluid passes through the suction pump 62, the suction pump 62 is operated in addition to the delivery pump 64 (or vacuum ejector 95), thereby further and effectively discharging the cleaned cleaning fluid toward the drain tank 65, which can further suppress the decrease in the cleanability of the paint circulation path 51 and the increase in cleaning time.

[0146] Additionally, as another example via at least the sixth switching valve 86, the cleaning control unit 150 switches the fifth switching valve 85, opening valves 85a and 85b and closing other valves 85c, 85d, 85e, and 85f. Furthermore, the cleaning control unit 150 switches the sixth switching valve 86, opening valves 86a and 86d and closing other valves 86b and 86c. Additionally, the cleaning control unit 150 switches the first switching valve 81, opening valves 81a and 81d and closing other valves 81b and 81c. Moreover, the cleaning control unit 150 switches the first three-way valve 71 so that the cleaning fluid does not flow towards the paint tank 57, but flows towards the drain trough 65.

[0147] In this case, cleaning fluid can also flow in the return flow path 53 between the 5th switching valve 85 and the 6th switching valve 86 for cleaning. Furthermore, cleaning fluid can also flow in the 2nd bypass flow path 56 for cleaning.

[0148] (3-3. Supply of cleaning fluid from sources other than the 5th switching valve 85) In addition, during the reverse cleaning described above, cleaning fluid is supplied from the valve section 85c of the fifth switching valve 85. However, cleaning fluid may also be supplied from the valve section 85c of the sixth switching valve 86.

[0149] In this case, the cleaning control unit 150 switches, for example, the sixth switching valve 86, opening valves 86a and 86c and closing the other valves 86b and 86d. Additionally, the cleaning control unit 150 switches the fifth switching valve 85, opening valves 85a and 85b and closing the other valves 85c, 85d, 85e, and 85f.

[0150] In this case, the cleaning fluid can also flow in the return flow path 53 between the 5th switching valve 85 and the 6th switching valve 86 for cleaning.

[0151] (3-4. Supply of cleaning fluid via the first switching valve 81, the second bypass flow path 56 and the sixth switching valve 86) In addition, during reverse cleaning, the cleaning control unit 150 can also supply cleaning fluid such as cleaning liquid or air from the first switching valve 81, and further supply cleaning fluid from the return flow path 53 side to the internal flow path 36 via the second bypass flow path 56 and the sixth switching valve 86.

[0152] At this time, the first switching valve 81 is switched so that valve sections 81c and 81d are opened, while the other valve sections 81a and 81b are closed. Similarly, the sixth switching valve 86 is switched so that valve sections 86a and 86d are opened, while the other valve sections 86b and 86c are closed. Furthermore, the fifth switching valve 85 is switched so that valve sections 85a and 85b are opened, while the other valve sections 85c, 85d, 85e, and 85f are closed. Thus, the cleaning fluid is supplied from the return flow path 53 to the internal flow path 36 via the first switching valve 81, the second bypass flow path 56, the sixth switching valve 86, and the fifth switching valve 85.

[0153] Furthermore, regarding the discharge of cleaning fluid from the paint supply path 52 side, switching of the second to fourth switching valves 82 to 84 is performed, causing the cleaning fluid to be discharged from at least one of the second to fourth switching valves 82 to 84. Specifically, when switching the second switching valve 82, its operation is controlled to open valve sections 82b and 82d, while closing the other valve sections 82a and 82c. Similarly, when switching the third switching valve 83, its operation is controlled to open valve sections 83b and 83d, while closing the other valve sections 83a and 83c. Furthermore, when switching the fourth switching valve 84, its operation is controlled to open valve sections 84b and 84e, while closing the other valve sections 84a, 84c, 84d, and 84f.

[0154] In this way, during reverse cleaning, when a cleaning fluid such as cleaning liquid or air is supplied from the first switching valve 81, and further supplied from the return flow path 53 side to the inner flow path 36 via the second bypass flow path 56 and the sixth switching valve 86, the return flow path 53 can be cleaned together with the cleaning of the coating head 31.

[0155] (3-5. Supply of cleaning fluid via the first switching valve 81, paint tank 57 and the sixth switching valve 86) In addition, during reverse cleaning, the cleaning control unit 150 can supply cleaning fluid such as cleaning liquid or air from the first switching valve 81, and further supply cleaning fluid from the return flow path 53 side to the internal flow path 36 via the paint tank 57 and the sixth switching valve 86.

[0156] At this time, the first switching valve 81 is switched so that valve sections 81a and 81c are opened, while the other valve sections 81b and 81d are closed. Additionally, the first three-way valve 71 is switched so that the cleaning fluid does not flow towards the drain tank 65, but flows towards the paint tank 57. Furthermore, the fourth three-way valve 74 is switched so that the cleaning fluid does not flow towards the drain tank 65, but flows towards the sixth switching valve 86.

[0157] Furthermore, the sixth switching valve 86 is switched so that valve sections 86a and 86b of the sixth switching valve 86 are open, while the other valve sections 86d and 86c are closed. Similarly, the fifth switching valve 85 is switched so that valve sections 85a and 85b of the fifth switching valve 85 are open, while the other valve sections 85c, 85d, 85e, and 85f are closed. Thus, the cleaning fluid is supplied from the return flow path 53 to the internal flow path 36 via the first switching valve 81, the paint tank 57, the sixth switching valve 86, and the fifth switching valve 85.

[0158] Furthermore, the discharge of the cleaning fluid from the paint supply path 52 side is the same as the supply of the cleaning fluid via the first switching valve 81, the second bypass flow path 56, and the sixth switching valve 86, so its description is omitted.

[0159] In this reverse cleaning process, the return flow path 53 can be cleaned simultaneously with the cleaning of the coating head 31. Additionally, the paint tank 57 can also be cleaned.

[0160] (3-6. Pressure variations based on cap 93) In the above-described embodiments or variations, the cover moving mechanism 94 can be activated under the control of the cleaning control unit 150 during at least one of the forward and reverse cleaning operations, thereby causing variations in the sealing pressure of the nozzle forming surface 32 and the internal flow path 36 based on the cover 93. Alternatively, the pressure of the nozzle forming surface 32 and the internal flow path 36 can be varied by releasing the sealing state of the nozzle forming surface 32 based on the cover 93 and then resealing it.

[0161] By generating such pressure variations, the discharge of foreign matter in the internal flow path 36 can be improved.

[0162] (3-7. Other variations) Furthermore, in the above embodiment, the delivery pump 64 is designated as the pressurizing mechanism, but other components may be designated as the pressurizing mechanism instead of the delivery pump 64. For example, when supplying cleaning fluid or air from a position upstream of the supply pump 61, the supply pump 61 may be designated as the pressurizing mechanism.

[0163] Furthermore, in the above embodiment, the first vacuum ejector 91 and the second vacuum ejector 92 are designated as the cleaning suction mechanism, but other components may be used instead. For example, when the cleaning fluid or air is supplied from a position upstream of the return flow path 53 from the suction pump 62, the suction pump 62 may be designated as the pressurization mechanism. Additionally, as the cleaning suction mechanism, at least one of the first vacuum ejector 91 and the second vacuum ejector 92 may be replaced by connecting a pump identical to the suction pump to valve section 84e and / or valve section 85e.

[0164] (4. Postscript) The contents described in the above embodiments shall be understood as follows, for example. [1] That is, A cleaning system 1 for a painting robot 10 that paints painted areas of a vehicle, comprising: The coating head unit 30 includes a coating head 31, which has a plurality of nozzles 33 that spray paint droplets in the main scanning direction and the sub-scanning direction, and has a plurality of internal flow paths 36 for supplying paint or cleaning fluid to the nozzles 33. Robotic arm R1, which has a painting head unit 30 mounted at its front end, and moves the painting head unit 30 to the desired position; Cover 93, which seals the nozzle forming surface 32, with the nozzle 33 exposed on the nozzle forming surface 32; The cover moving mechanism 94 moves the cover 93 relative to the nozzle forming surface 32 to achieve a sealing state of the nozzle forming surface 32; Paint supply path 52 supplies paint or cleaning fluid toward paint head 31; Return flow path 53, which is connected to the paint discharge side of the coating head 31, recovers paint or cleaning fluid that was not sprayed from the nozzle 33; A pressurizing mechanism (discharge pump 64) pressurizes the cleaning fluid supplied toward the coating head 31 in at least one of the paint supply path 52 and the return flow path 53; and The control mechanism (main control unit 110, cleaning control unit 150) controls the operation of the pressurization mechanism (discharge pump 64). The control mechanism (main control unit 110, cleaning control unit 150) controls the operation of the cover moving mechanism 94, so that the nozzle forming surface 32 is sealed by the cover 93. The control mechanism (main control unit 110, cleaning control unit 150) controls the operation of the pressurization mechanism (discharge pump 64) so ​​that the cleaning fluid is supplied to the internal flow path 36 in a pressurized state.

[0165] In this manner, with the robot arm R1 operating and the nozzle forming surface 32 sealed by the cover 93, the pressurizing mechanism (discharge pump 64) is activated to supply cleaning fluid to the internal flow path 36 of the coating head 31. This prevents the cleaning fluid from flowing out of the nozzle 33. Therefore, the supply pressure of the cleaning fluid in the internal flow path 36 can be increased, and the internal flow path 36 and the nozzle 33 can be effectively cleaned using the cleaning fluid, thus eliminating blockages in the internal flow path 36 and the nozzle 33.

[0166] In addition, the cleaning performance of the nozzles 33 and internal flow path 36 of the coating head 31 can be improved without the need for large-scale dedicated equipment for cleaning.

[0167] [2] Alternatively, in the above embodiments, it is also possible to base the content described in [1] above on the following: It is equipped with a suction mechanism (at least one of a first vacuum ejector 91 and a second vacuum ejector 92) that suctions the cleaning fluid after cleaning the coating head 31 in at least one of the paint supply path 52 and the return flow path 53. The control mechanism (main control unit 110, cleaning control unit 150) controls the operation of the suction mechanism (at least one of the first vacuum ejector 91 and the second vacuum ejector 92) so that after the cleaning fluid is supplied to the internal flow path 36 in a pressurized state through the pressurizing mechanism (delivery pump 64), the cleaning fluid in the internal flow path 36 is discharged.

[0168] In this way, by activating the suction mechanism (at least one of the first vacuum ejector 91 and the second vacuum ejector 92) to discharge the pressurized cleaning fluid in a suction state, the dischargeability of foreign matter present in the internal flow path 36 and the nozzle 33 can be improved, along with the dischargeability of the cleaning fluid. Therefore, the cleaning performance of the internal flow path 36 and the nozzle 33 of the coating head 31 can be improved.

[0169] [3] Alternatively, in the above embodiments, it is also possible to base the content described in [1] and [2] or a combination thereof, The paint supply path 52 is provided with a first pressurizing mechanism (opening of either the fourth switching valve 84 or the fifth switching valve 85 and the delivery pump 64) corresponding to the pressurizing mechanism and a first suction mechanism (either of the first vacuum ejector 91 or the second vacuum ejector 92) corresponding to the suction mechanism. The return flow path 53 is provided with a second pressurizing mechanism (the opening of either the fourth switching valve 84 or the fifth switching valve 85 and the delivery pump 64) corresponding to the pressurizing mechanism and a second suction mechanism (the other of the first vacuum ejector 91 and the second vacuum ejector 92) corresponding to the suction mechanism. The control mechanism (main control unit 110, cleaning control unit 150) controls the execution of forward and reverse cleaning. In forward cleaning, after the first pressurizing mechanism (the opening of either the fourth switching valve 84 or the fifth switching valve 85 and the delivery pump 64) is activated to supply cleaning fluid to the internal flow path 36 under pressure via the paint supply path 52, the second suction mechanism (the other of the first vacuum ejector 91 and the second vacuum ejector 92) is activated to discharge the cleaning fluid from the internal flow path 36 via the return flow path 53. In reverse cleaning, after the second pressurizing mechanism (the opening of either the fourth switching valve 84 or the fifth switching valve 85 and the delivery pump 64) is activated to supply cleaning fluid to the internal flow path 36 in a pressurized state via the return flow path 53, the first suction mechanism (the other of the first vacuum ejector 91 and the second vacuum ejector 92) is activated to discharge the cleaning fluid from the internal flow path 36 via the paint supply path 52.

[0170] By performing forward and reverse cleaning in this way, the removal of foreign matter present in the internal flow path 36 and nozzle 33 can be improved. Therefore, the cleanliness of the internal flow path 36 and nozzle 33 of the coating head 31 can be improved.

[0171] [4] In addition, in the above embodiments, it is also possible to base the content described in any one of [1] to [3] above, or a combination thereof, on the following: When performing at least one of the cleaning actions of forward cleaning and reverse cleaning, the control mechanism (main control unit 110, cleaning control unit 150) activates the cover moving mechanism 94 to change the sealing pressure of the nozzle forming surface 32 based on the cover 93, or re-seals after releasing the sealing state of the nozzle forming surface 32 based on the cover 93.

[0172] In this way, by operating the cap moving mechanism 94, the sealing pressure of the nozzle forming surface 32 based on the cap 93 is varied, preventing, for example, cleaning fluid from leaking out of the nozzle 33. This improves the removal of foreign matter present in the internal flow path 36 and the nozzle 33, thus enhancing cleaning performance. Furthermore, by releasing the seal on the nozzle forming surface 32 based on the cap 93, the flow direction of cleaning fluids such as cleaning liquid and air in the internal flow path 36 and the nozzle 33 within the coating head 31 is significantly altered. Therefore, the removal of foreign matter present in the internal flow path 36 and the nozzle 33 is improved, further enhancing cleaning performance.

Claims

1. A cleaning system for a painting robot, characterized in that, The painting robot uses a cleaning fluid containing at least one of a cleaning liquid and air to paint the areas of a vehicle, and the cleaning system includes: A coating head unit includes a coating head having a plurality of nozzles arranged in a main scanning direction and a sub-scanning direction for ejecting droplets of coating material, and having a plurality of internal flow paths for supplying the coating material or the cleaning fluid to the nozzles. A robotic arm that has the coating head unit mounted at its front end and moves the coating head unit to a desired position; A cover that seals the nozzle forming surface, with the nozzle exposed at the nozzle forming surface; A cover moving mechanism that moves the cover relative to the nozzle forming surface to achieve a sealing state of the nozzle forming surface; A paint supply path that supplies the paint or the cleaning fluid toward the coating head; The return flow path is connected to the paint discharge side of the coating head and recovers any paint or cleaning fluid that was not sprayed from the nozzle. A pressurizing mechanism that pressurizes the cleaning fluid supplied toward the coating head in at least one of the paint supply path and the return flow path; as well as The control mechanism controls the operation of the pressurizing mechanism. The control mechanism controls the operation of the cover moving mechanism, so that the nozzle forming surface is sealed by the cover. The control mechanism controls the operation of the pressurizing mechanism, thereby supplying the cleaning fluid to the internal flow path under pressurization.

2. The cleaning system for the painting robot according to claim 1, characterized in that, The device includes a suction mechanism that, at least one of the paint supply path and the return flow path, draws in the cleaning fluid after the painting head has been cleaned. The control mechanism controls the operation of the suction mechanism so that after the cleaning fluid is supplied to the internal flow path in a pressurized state through the pressurizing mechanism, the cleaning fluid in the internal flow path is discharged.

3. The cleaning system for the painting robot according to claim 2, characterized in that, The paint supply path is provided with a first pressurizing mechanism corresponding to the pressurizing mechanism and a first suction mechanism corresponding to the suction mechanism. The return flow path is provided with a second pressurizing mechanism corresponding to the pressurizing mechanism and a second suction mechanism corresponding to the suction mechanism. The control mechanism controls the execution of forward and reverse cleaning, wherein... In the forward cleaning process, after the first pressurizing mechanism is activated to supply the cleaning fluid to the internal flow path under pressure via the paint supply path, the second suction mechanism is activated to discharge the cleaning fluid from the internal flow path via the return flow path. In the reverse cleaning, after the second pressurizing mechanism is activated to supply the cleaning fluid to the internal flow path in a pressurized state via the return flow path, the first suction mechanism is activated to discharge the cleaning fluid from the internal flow path via the paint supply path.

4. The cleaning system for the painting robot according to claim 3, characterized in that, When the control mechanism performs at least one of the forward cleaning and reverse cleaning actions, it causes the cover moving mechanism to operate, causing the sealing pressure of the nozzle forming surface generated by the cover to change, or to re-seal after releasing the sealing state of the nozzle forming surface generated by the cover.

Images