Robots, systems and methods for electrostatic powder coating

Abstract

The present application relates to a robot, system and method for electrostatic powder coating. An electrostatic powder applicator robot (4) for an electrostatic coating powder booth (2) comprises a projector (41) for electrostatic powder application; a mechanical arm (43) articulated and carrying said projector (41) to position said projector (41); and a blower (42) for blowing a powder removal fluid, wherein said mechanical arm (43) carries the blower (42) to position the blower (42) within the booth (2) so that the blower (42) blows the powder removal fluid onto a surface to be powder removed within the electrostatic coating powder booth (2) to remove residual powder coating from the surface to be powder removed. The robot can reduce the time required to remove powder from the powder booth and facilitate the automation of powder removal.

Description

Technical Field

[0001] The present invention relates to a robot for electrostatic powder coating, an electrostatic powder coating system including such a robot, and an electrostatic powder coating method performed using such a robot or system. Background Technology

[0002] An electrostatic powder chamber is known, in which an electrostatic powder is applied to a workpiece to apply a coating, such as paint, onto the workpiece. The powder is applied to the workpiece using an electrostatic projector that emits a stream of powder while the projector and the workpiece are raised to a specific potential, causing the powder to be attracted to the workpiece for coating. Once the workpiece is electrostatically powder coated, it is transported to an oven. The oven heats the powder to a certain temperature, causing the thermosetting material in the powder to form a network, thereby adhering the coating to the workpiece.

[0003] Despite the electrostatic effect, some powder intended for the workpiece does not reach it, but tends to deposit on the walls and floor of the chamber, and even on the projector itself. Generally, coating chambers are equipped with a residual powder suction system to create a vacuum inside the chamber, allowing most of the powder to be recovered for recycling and mixed with new powder for coating subsequent workpieces. However, despite this vacuum system, residual powder often remains adhered to the walls and floor, necessitating powder removal—that is, cleaning the interior of the coating chamber and the projector, especially if one wishes to change the type of powder, such as changing the color. When operated manually by an operator, this operation requires interrupting the coating chamber for safety reasons.

[0004] WO96 / 12568A1 describes a powder chamber with a powder projector and an automatic cleaning unit. However, this automatic cleaning unit is particularly bulky and only suitable for one type of chamber shape. Furthermore, each cleaning operation requires bringing the cleaning unit from the outside into the chamber, which is very time-consuming. Summary of the Invention

[0005] The present invention aims to overcome the shortcomings of the prior art by providing a novel electrostatic powder coating robot, which reduces the time required to remove powder from the chamber and facilitates the automation of powder removal.

[0006] This invention relates to an electrostatic powder coating robot for an electrostatic powder coating chamber, the robot including a projector configured to perform electrostatic powder application. According to the invention, the electrostatic powder coating robot further includes: a robotic arm hinged to and carrying the projector, such that the projector is positioned within the electrostatic powder coating chamber, allowing the projector to electrostatically powder coat articles within the chamber; and a blower configured to blow a powder removal fluid, preferably air, the robotic arm carrying the blower positioning it within the electrostatic powder coating chamber, such that the blower blows the powder removal fluid onto the surface of the powder to be removed within the chamber, thereby removing residual powder coating from the surface of the powder to be removed.

[0007] One idea behind this invention is to equip the same electrostatic powder coating robot with a projector and a blower, allowing the same robot to perform both electrostatic powder coating and powder removal, i.e., cleaning of residual powder. The robotic arm positions, i.e., moves, guides, and / or manipulates, the projector and the blower. Thus, when the article to be coated is present in the powder chamber, the robotic arm positions the projector near the article while simultaneously pointing it at the article to automatically apply powder. Once the article has been powdered, the powder chamber is ready to remove powder because the powder robot is permanently equipped with a blower. The robotic arm can then immediately position the blower to remove powder from the surface to be powdered by pointing it at the surface. Powder removal can be performed at any desired time, especially between powder coatings of two consecutive articles. Because the robotic arm positions the blower, the surface to be powdered can also be the inner wall of the chamber, the floor of the chamber, the ceiling of the chamber, or the surface of another projector or robot located in the chamber. This possibility of positioning the blower with the robotic arm makes powder removal particularly flexible and convenient, as any desired surface within the chamber can be powdered by properly positioning the blower with the robotic arm. Just as the robotic arm is programmed to apply powder by the projector, it can also be programmed to remove powder by the blower. Therefore, powder removal can be easily automated.

[0008] Preferably, the robotic arm includes a support head that carries the projector and the hair dryer, allowing the projector and the hair dryer to move as a whole via the robotic arm.

[0009] Preferably, the robotic arm is a multi-joint arm configured to position the projector and the hair dryer in at least five degrees of freedom.

[0010] Preferably, the projector includes a first row of electrostatic projection heads; and the blower includes a row of blow nozzles arranged parallel to the first row of electrostatic projection heads.

[0011] Preferably, the projector includes a second row of electrostatic projection heads arranged parallel to the first row of electrostatic projection heads, and the row of blowing nozzles is arranged between the first and second rows of electrostatic projection heads.

[0012] Preferably, the projector includes a powder-applying electrode, and electrostatic powdering includes raising the powder-applying electrode to a powder-applying potential. Preferably, the electrostatic powdering robot also includes a powder-removing electrode independent of the powder-applying electrode, which is configured to rise to an antistatic potential when a blower applies powder removal fluid to the surface of the powder to be removed.

[0013] The present invention also relates to an electrostatic powdering system, comprising: an electrostatic powdering robot as described above; and an electrostatic powder coating chamber. The electrostatic powdering robot is arranged such that a robotic arm can position a projector inside the electrostatic powder coating chamber, causing the projector to electrostatically powder an article within the electrostatic powder coating chamber, and that the robotic arm can position a blower inside the electrostatic powder coating chamber, causing the blower to blow powder removal fluid onto the surface of the powder to be removed within the electrostatic powder coating chamber.

[0014] Preferably, the electrostatic powdering system further includes another robot located within the electrostatic powder coating chamber. Preferably, the robotic arm is configured to position a blower, enabling the blower to deliver powder removal fluid to the other robot for powder removal from the other robot.

[0015] Preferably, the powder application system further includes an auxiliary blower located within the electrostatic powder coating chamber and configured to blow powder removal fluid. Preferably, the robotic arm is configured to position the projector near the auxiliary blower, such that the auxiliary blower blows powder removal fluid onto the projector to remove powder from the projector.

[0016] Preferably, the blower is detachable from the robotic arm. Preferably, the electrostatic powdering system includes a tool changing device designed to make the blower available to the robotic arm when detached from it. Preferably, when the blower is detached from the robotic arm and available to it via the tool changing device, the robotic arm is adapted to automatically attach the blower at the tool changing device to carry it for powder removal from the surface to be powdered.

[0017] Another object of the present invention is an electrostatic coating method, which is implemented by means of an electrostatic powdering robot or a powdering system as defined above. The electrostatic powdering method includes: electrostatically powdering an article by means of a projector, wherein the projector is positioned in an electrostatic powder coating chamber by a robotic arm, and once electrostatic powdering has been performed, blowing a powder removal fluid onto the surface of the powder to be removed by means of a blower, wherein the blower is positioned in the electrostatic powder coating chamber by a robotic arm. Attached Figure Description

[0018] Based on the principles of the invention illustrated in the accompanying drawings, the invention will be better understood through the following description of embodiments, and other advantages of the invention will become apparent, wherein:

[0019] Figure 1 This is a schematic cross-sectional view of an electrostatic powdering system including an electrostatic powdering robot according to an embodiment of the present invention.

[0020] Figure 2 yes Figure 1 A perspective view of a portion of an electrostatic powdering robot.

[0021] Figure 3 yes Figure 1 and 2 An exploded perspective view of a portion of an electrostatic powdering robot. Detailed Implementation

[0022] Figure 1 An electrostatic powdering system is shown, which includes an electrostatic powder coating chamber 2, an electrostatic powdering robot 4, and an electrostatic powdering robot 6.

[0023] When the product 10 is located in chamber 2, chamber 2 is used to accommodate the electrostatic powdering operation of the product 10 using robots 4 and 6 for powdering.

[0024] exist Figure 1 In the example shown, chamber 2 includes a floor 12, a roof 14 extending above the floor 12, and an outer wall 16 connecting the floor 12 to the roof 14 along their respective perimeters. Chamber 2 defines a substantially enclosed powder chamber within itself, defined by the floor 12, roof 14, and outer wall 16, in which powdering takes place. Chamber 2 is primarily intended to collect any residual powder that does not reach the article 10 during the powder processing.

[0025] The interior of room 2, at least for the floor 12, roof 14 and walls 16, is preferably made of or lined with an electrically insulating material, such as a polymeric plastic material.

[0026] Chamber 2 advantageously includes an access opening 18 disposed through the outer perimeter wall 16 for introducing article 10 into chamber 2. Article 10 can be removed from chamber 2 through the same access opening 18 or through a second similar access opening, for example, disposed opposite to opening 18 at the other end of chamber 2.

[0027] The powder system preferably includes a conveyor 19 for introducing the article 10 into the chamber 2 through an opening 18 and removing the article 10 from the chamber 2 through the opening 18 or another opening. The conveyor 19 includes a track 25 on which the article 10 is suspended, for example, the track carrying a device for driving the article 10 along the track, such as a belt or chain. The track 25 is advantageously arranged above a roof 14, which advantageously provides a longitudinal slit 26 following the track 25 below it. As the article 10 passes through the interior of the chamber 2, it is suspended on the track 25 through the slit 26. Preferably, the article 10 is moved by the conveyor 19 without stopping within the chamber 2, and powdering of the article 10 is performed while the conveyor 19 continuously generates the forward motion of the article 10.

[0028] Preferably, the conveyor 19 is designed to continuously carry multiple products distributed along the track 25 for continuously powdering these products within the chamber 2.

[0029] Advantageously, the powder coating system includes a suction system connected to chamber 2 to suction residual powder contained within chamber 2. For example, the suction system includes a powder suction conduit 21 located below floor 12 and a vent 22 disposed through floor 12 to connect the interior of chamber 2 to conduit 21 in a circulating manner, allowing residual powder contained in chamber 2 to enter conduit 21 through the vent 22. Preferably, as shown, the base plate 12 is formed of an assembly with inclined portions to facilitate the flow of residual powder into the vent 22.

[0030] The suction of residual powder advantageously creates a negative pressure inside chamber 2 relative to the outside of chamber 2, thereby allowing air intake through any opening in chamber 2, such as opening 18 and / or cut 26, which prevents residual powder from escaping from the chamber through these openings.

[0031] For suction, the suction system includes a powder suction pump 20 or any other suitable pumping device. The pump 20 is located outside the chamber 2 and connected to a conduit 21 to suction residual powder out of the chamber 2 via the conduit 21 and through the vent 22.

[0032] Preferably, all or part of the residual powder thus inhaled can be reintroduced into chamber 2 for electrostatic powdering after the residual powder has been treated and / or mixed with fresh powder.

[0033] Article 10 is schematically shown Figure 1 In general, powder coating can be applied to any type of product, especially metal products, such as bicycle frames, furniture bodies, or parts.

[0034] Powder is applied to article 10 by electrostatic powdering in chamber 2, with the aim of forming a coating on article 10. Electrostatic powder coating allows the powder to be applied to article 10 in a desired distribution, applied to the desired portion of article 10. Then, outside chamber 2, the powder can be reacted to cure the coating and impart its final properties without affecting any subsequent processing. To allow the powder to react and thus fix the coating, it is preferable to heat-treat article 10 using an oven. The resulting coating is preferably a paint or varnish applied to article 10.

[0035] Preferably, the powder comprises a thermosetting polymeric material. Once the article 10 is coated with the powder in chamber 2, heat treatment applied to the article 10 causes the thermosetting material to harden, resulting in a network structure, thereby curing the coating.

[0036] In this example, robots 4 and 6 are identical, therefore the description of robot 4 applies to robot 6. In one variation, robot 6 differs from robot 4. In one variation, an electrostatic powdering system may be provided comprising a single electrostatic powdering robot, or multiple electrostatic powdering robots in addition to two. These robots may be identical or different. In particular, robots 4 and 6 may be provided that are different from each other, but both include a corresponding blower and projector as described below, and a corresponding robotic arm for positioning the blower and projector as described below. In one variation, robots 4 and 6, both powder robots, may be provided, but only robot 4 includes a blower, while the other does not.

[0037] Here, Robot 4 is completely arranged inside Room 2. Robot 4 mainly includes a projector 41, a blower 42, and a robotic arm 43.

[0038] The robotic arm 43 carries the projector 41 and the blower 42 to position them within the chamber 2, that is, to move and orient them to a desired location within the chamber 2. In other words, the projector 41 and the blower 42 can be positioned by means of the arm 43, which acts as a movable support for them. For this purpose, the arm 43 is articulated.

[0039] Preferably, the robotic arm 43 is in the form of a multi-joint arm, i.e., a multi-axis robot. Therefore, the robotic arm 43 allows the projector 41 and the blower 42 to be positioned within the chamber 2 according to any desired setup, and in particular, to be adapted to the shape of the chamber 2 and the article 10 through simple control and / or programming of the robotic arm 43.

[0040] The robotic arm 43 includes a base 45 and a support head 46, and preferably a plurality of components connecting the base 45 to the support head 46, in this example being components 47, 48, 49 and 50.

[0041] The robotic arm 43 is preferably completely housed within the chamber 2. In a variation, a portion of the arm 43 may be located outside the chamber 2, for example, at the base 45.

[0042] The robotic arm 43 is supported by a base 45. For this purpose, the base 45 is advantageously fixed to the room 2, which is fixed to the floor of the room 2. The base 45 supports the projector 41 and the blower 42 by means of components 47, 48, 49 and 50 and a support head 46.

[0043] Component 47 is supported by base 45 and is motorically hinged relative to base 45, preferably via motor hinge 51, where it pivots in a yaw manner. Component 47 supports other components 49 and 50, support head 46, projector 41, and blower 42 via component 48. Therefore, movement of component 47 relative to base 45 causes overall movement of components 48, 49, and 50, support head 46, projector 41, and blower 42 relative to chamber 2.

[0044] Component 48 is supported by component 47 and is kinematically hinged relative to component 47, preferably via kinematic joint 52, where it pivots in a pitching manner. Component 48 supports component 50, support head 46, projector 41, and blower 42 via component 49. Therefore, movement of component 48 relative to component 47 results in overall movement of components 49 and 50, support head 46, projector 41, and blower 42 relative to component 47.

[0045] Component 49 is supported by component 48 and is motorically hinged relative to component 48, preferably via motor joint 53, where it pivots in a pitching manner. Component 49 supports the support head 46, projector 41, and blower 42 via component 50. Therefore, movement of component 49 relative to component 48 results in overall movement of component 50, support head 46, projector 41, and blower 42 relative to component 48.

[0046] Component 50 is supported by component 49 and is motorically hinged relative to component 49, preferably via motor hinge 54, where it pivots in a rolling manner. Component 50 supports the projector 41 and the blower 42 via support head 46. Therefore, movement of component 50 relative to component 49 causes overall movement of support head 46, projector 41, and blower 42 relative to component 49.

[0047] The support head 46 is supported by the member 50 and pivots in a pitching manner relative to the member 50 via a motor hinge, preferably via a motor hinge 55. The support head 46 supports the projector 41 and the blower 42. Therefore, movement of the support head 46 relative to the member 50 causes overall movement of the projector 41 and the blower 42 relative to the member 50.

[0048] Due to this structure, the robotic arm 43 of this example allows the projector 41 and the blower 42 to be positioned relative to the chamber 2 with five degrees of freedom. These five degrees of freedom include two translational degrees of freedom relative to the chamber, namely height and lateral position changes, and three rotational degrees of freedom, namely pitch, roll, and yaw. However, the robotic arm 43 can be specified to have multiple degrees of freedom in addition to five, particularly six. Furthermore, it is preferred that the components of the robotic arm 43 be arranged in series as shown in the example, with a given component hingedly supported by a preceding component and hingedly supporting a subsequent component, the first component hingedly supported by a base 45, and the last component hingedly supporting the support head 46. Depending on the situation, multiple components other than four can be provided, preferably at least two components arranged in this way, with the first component hingedly supported by the base, the second component hingedly supported by the first component, and the head hingedly supported.

[0049] Preferably, the robot 4 includes an electronic unit 56 for controlling the positioning of the projector 41 and the blower 42 via the robotic arm 43, for example, in a pre-programmed manner and / or manually. For this purpose, the electronic unit 56 controls the robotic arm 43, particularly by controlling the motorized joints 51, 52, 53, 54, and 55 to manipulate the positioning of the components, thereby positioning the projector 41 and the blower 42. For example, the unit 56 includes an electronic controller connected via wires to each joint for control, and also connected via wires to a human / machine interface for human programming and control of the electronic controller.

[0050] Figure 2 and 3 A preferred embodiment of the support head 46, projector 41, and hair dryer 42 is shown in more detail. The hair dryer 42... Figure 3 It is shown separately in the text.

[0051] For this purpose, the projector 41 is configured to be positioned within chamber 2 by a robotic arm 43 to electrostatically powder the article 10. Although the entire robot 4 is inside chamber 2, it is intended that at least the projector 41 and the blower 42 are inside chamber 2 so that the emitted powder remains trapped within chamber 2.

[0052] Projector 41 here includes eight projection heads 61. However, the projector may consist of a single projection head or multiple projection heads other than eight.

[0053] Advantageously, each projection head 61 is in the form of an automatic gun and is attached to the support head 46 of the robotic arm 43, thus being immovable relative to the support head 46.

[0054] Each projection head 61 includes a flat, round, or vortex nozzle 62 to spray a powder spray of the desired shape onto the article 10. All projection heads 61 may be selected to have the same nozzle 62, or different nozzles may be provided to produce jets with different characteristics.

[0055] Preferably, the corresponding nozzle 62 of each projection head 61 is individually supplied with powder via, for example, a corresponding supply line 63 connected to the rear of the corresponding projection head 61. Preferably, the powder can be selectively sprayed only through selected projection heads 61. Preferably, the powder is guided to the nozzle 62 via the line 63 by a powder pump, which itself is supplied with fresh powder from a fresh powder supply source and / or with recovered powder from residual powder recovered by the aforementioned suction system.

[0056] As an alternative to nozzle 62, each projection head 61 may have a rotating bowl.

[0057] Advantageously, the powder supplied to each projection head 61 is different from the powder supplied to the other heads, for example, a powder of a different color, or a powder intended to form a varnish, while another powder is intended to form a paint or primer.

[0058] In one variant, the same powder can be supplied to all or several projection heads 61 and / or they can work together.

[0059] Each projection head 61 also incorporates a high-voltage unit 66. Figure 2 The diagram schematically illustrates, in perspective, the electrode 64 of a single projection head 61, powered by a high-voltage unit 66. The high-voltage unit 66 imparts a potential to the electrode 64, termed the "powder application potential." The powder application potential is a high-voltage potential, preferably continuous. When the electrode 64 reaches the powder application potential, it applies this potential directly to the powder in the powder jet, or to the vicinity of the powder jet, to achieve a corona effect. For example, the electrode 64 may be formed at the end of the projection head 61, or in the form of multiple electrodes surrounding the projection head.

[0060] To generate an electrostatic field that causes the powder from the powder jet to adhere to the article 10, preferably, the article 10 is grounded, and the powder application potential is a negative DC potential, for example, -80 kV. More generally, a powder application potential between -70 kV and -90 kV is preferred. "Continuous" means that the powder application potential applied by electrode 64 does not change sign. In a variation, depending on the application, powder type, and article type, a powder application potential with a positive sign may be provided, for example, at +70 kV. Preferably, the article 10 is grounded via conveyor 19, wherein conveyor 19 itself is grounded. More generally, a high-voltage potential difference is provided between electrode 64 and article 10, wherein the powder application potential of electrode 64 differs significantly from the potential of article 10, particularly the powder application potential of electrode 64 is much lower than the potential of article 10.

[0061] For electrostatic powder application, all projection heads 61 can operate simultaneously. In one variation, certain projection heads 61 can be selectively activated, particularly if projection heads 61 emit different powders and / or jets with different properties, or if it is desired to change the powder of one projection head 61 while the powder is being carried by other projection heads 61.

[0062] In this example, such as Figure 2 As shown, the projection heads 61 are arranged in two parallel rows 71 and 72. Here, rows 71 and 72 have the same number of projection heads 61. For example, for each row 71 and 72, the projection heads 61 are arranged at regular intervals. Preferably, each projection head 61 in row 71 is positioned opposite to one projection head 61 in row 72. Therefore, the heads 61 can also be considered to be arranged in pairs, with each pair including one projection head 61 in row 71 and one projection head in row 72. For example, for each pair, the two projection heads 61 are arranged in a column perpendicular to rows 71 and 72.

[0063] Preferably, during the use of the projector 41 and its positioning by the robotic arm 43, the projector head 61 is fixed relative to the support head 46. The projector 41 is designed to electrostatically powder the article 10 while the article 10 is positioned in a predetermined area in front of the projector 41. In other words, the projector 41 will be positioned pointing towards the article 10 and within a predetermined distance from the article 10. This range may depend on which projector head(s) 61 is performing electrostatic powdering at the time. In this example, all projector heads 61 are oriented along the same direction X41 fixed relative to the support head 46, or at least along a direction close to direction X41. For example, for each pair of heads 61, the two heads are oriented along a converging direction consistent with direction X41.

[0064] In summary, electrostatic powdering of product 10 means that when projector 41 is located inside chamber 2 to aim at product 10, and when projector 41 is at a predetermined distance from product 10, projector 41 emits a powder jet and applies a high voltage potential difference between projector 41 and product 10. Specifically, this condition is met when one of the projection heads 61 emits a powder jet while generating a high voltage potential difference, and simultaneously when projection head 61 is correctly positioned relative to product 10. During the electrostatic powder coating process, projector 41 can be stationary or moving under the action of robotic arm 43 to coat product 10 with powder.

[0065] Electrostatic powdering of article 10 is advantageously performed jointly by robots 4 and 6 using their respective projectors, for example, each robot performs electrostatic powdering on opposite sides of article 10 or on mutually distant portions of article 10.

[0066] The blower 42 is configured to blow air toward the surface of the powder to be removed within chamber 2. For this purpose, the blower 42 is positioned within chamber 2 by a robotic arm 43. The air can be ejected continuously or in pulses as one or more jets, preferably flat jets. The purpose of this blowing is to remove (i.e., separate) residual powder covering the surface of the powder to be removed, which may have been accidentally deposited during electrostatic powdering. Removing the residual powder effectively suspends it within chamber 2, thus facilitating its suction by the aforementioned suction system. Preferably, the suction system is activated during and / or after the blower 42 performs powder removal.

[0067] Advantageously, the blower 42 blows air instead of another fluid because the same compressed air generator can be used for both the powder sprayer 41 and the blower 42 for powder removal. Since air is a gas that does not mix with residual powder, the residual powder is not contaminated and can be more easily reused for further electrostatic powdering. However, it is possible for the blower 42 to blow or spray any other suitable powder removal fluid, such as another gas or even a liquid.

[0068] Any surface within chamber 2 can be the surface from which powder is to be removed, as long as the robotic arm 43 can position the blower 42 to remove the powder from that surface. Specifically, the surface from which powder is to be removed can be all or part of the floor 12, walls 16, and roof 14. The surface from which powder is to be removed can also be part of the conveyor 19 located inside chamber 2.

[0069] Advantageously, it is conceivable that the blower 42 of robot 4 performs all or part of the powder removal on another robot 6, which constitutes the surface from which the powder is to be removed. Specifically, robot 4 can perform powder removal on the projector 41 or blower 42 of another robot 6. Conversely, if robot 6 is equipped with a blower 42, then robot 6 can perform powder removal on robot 4. More generally, robot 4 can be responsible for powder removal from any robot or device contained in chamber 2, whether it is a powder robot, a robot with another function (e.g., handling article 10), or another automated device contained in chamber 2, such as a lift or wiring.

[0070] In one variation, article 10 may be provided as a surface from which powder is to be removed, for example, if an incorrect powder coating has been applied to article 10, if it is necessary to remove excess powder from article 10, or to obtain a specific surface finish of article 10.

[0071] exist Figure 2 and 3 The hair dryer 42 shown in detail includes six nozzles 81. However, the hair dryer 42 may consist of a single air nozzle 81 or a number other than six nozzles 81.

[0072] Each nozzle 81 is attached to the support head 46 of the robotic arm 43 and is therefore immovable relative to the support head 46. Thus, the nozzle 81 is preferably stationary relative to the projection head 61. More generally, the fact that the projector 41 and the blower 42 are carried on a single support head 46 means that they are moved simultaneously by the robotic arm 43, i.e., moved as a whole, as described above. Preferably, the projector 41 and the blower 42 are configured to be stationary relative to the support head 46 during electrostatic powder coating and powder removal.

[0073] Nozzles 81 are supplied with powder removal fluid, in this case air, via a supply manifold 82, which simultaneously distributes a single flow of powder removal fluid to all nozzles 81. In other words, supplying fluid to the manifold 82 causes fluid to be ejected from all nozzles 81 simultaneously. Preferably, nozzles 81 are attached to support head 46 via manifold 82, i.e., manifold 82 itself is attached to support head 46.

[0074] Here, the air nozzle 81 is arranged in a row 91 between the two rows 71 and 72, which is parallel to the rows 71 and 72 of the projection head 61.

[0075] Each blowing nozzle 81 is advantageously in the form of a flat jet nozzle, which is particularly effective for removing residual powder. Advantageously, each nozzle 81 is oriented such that the flat jet is oriented along the X41 direction, parallel to the direction of the row 91 and X41. In this configuration, the combination of the flat jets from the nozzles 81 forms a flat powder removal fluid flow, i.e., a planar powder removal fluid curtain, oriented along the X41 direction parallel to the row 91. This is particularly effective in separating residual powder from the surface for powder removal.

[0076] In one variation, it is possible to provide all or some of the blowing nozzles that emit jets of different shapes, such as circular jets.

[0077] Preferably, the projector 41 and the blower 42 are oriented in the same direction X41, which helps in programming the robotic arm 43 for positioning the head 61 and the nozzle 81, wherein the powder and the powder removal fluid flow are sprayed in the same direction.

[0078] Preferably, powder removal is performed simultaneously with the closing of the inlet opening 18 to prevent residual powder from dispersing outside the chamber 2. Preferably, powder removal is performed when no electrostatic powdering is being performed in the chamber 2. Preferably, powder removal is performed when there are no articles to be coated with powder or already coated with powder in the chamber 2 to prevent separated residual powder from accidentally contaminating the surface of the articles. In other words, one or more articles 10 are first electrostatically powdered using the projector 41. Then, once powdering is complete, air is blown using the blower 42. Further powder coating can then be applied to other articles.

[0079] Advantageously, since the blower 42 is always arranged in chamber 2, blowing is performed automatically between the coating powders of two consecutive products. For example, it can be anticipated that powder removal is systematically and automatically performed when two consecutive products are sufficiently spaced along conveyor 19, or if the supply of products to chamber 2 is temporarily interrupted. Powder removal can be performed by one robot at a time, or by multiple robots simultaneously.

[0080] Optionally, the hair dryer 42 may include an electrode 83, referred to as a "powder removal electrode," which is independent of any powder electrode that may be carried by the projector 41. The electrode 83 may be in the form of a single electrode or multiple electrodes. Here, the electrode 83 belongs to a deionization bar, sometimes referred to as an "ionization bar" or "active antistatic bar," which, for example, is integrated with the manifold 82, or otherwise integrated with the hair dryer 42. In one variation, the electrode 83 may be carried by another part of the robot 4, or may even be arranged elsewhere in the chamber 2.

[0081] The purpose of electrode 83 is to improve the powder removal efficiency of the surface from which the powder is to be removed, particularly if the surface is the floor 12, wall 16, or roof 14. For this purpose, electrode 83 is raised to a potential referred to as the "powder removal potential," which is designed to deionize the powder removal fluid, the air near the surface from which the powder is to be removed, the surface from which the powder is to be removed, and / or residual powder that rises during blowing. This avoids the tendency of residual powder to stick back to the surface from which the powder is to be removed or to another surface due to electrostatic effects. For this purpose, the powder removal potential is preferably an AC high-voltage potential, or at least a high-voltage potential whose value changes sign. For example, an AC high-voltage potential is expected to be 10 kV. More generally, a potential of at least 7 kV is anticipated. Advantageously, it is conceivable that electrode 83 reaches the powder removal potential via a high-voltage unit belonging to blower 42 or elsewhere on the robot or even externally carried. Here, this high-voltage unit is incorporated into the deionization bar. In any case, the high-voltage unit for electrode 83 is preferably separate from high-voltage unit 66.

[0082] In addition, or in a variant, it is foreseeable that the hair dryer 42 itself is equipped with one or more electrodes that are subjected to high voltage during the blowing process in order to facilitate the separation of residual powder.

[0083] In summary, blowing powder onto a surface to be removed means that while the blower 42 is positioned inside chamber 2 to be aligned with the surface to be removed, the blower 42 simultaneously sprays a powder-removing fluid at a predetermined distance from the surface. During the blowing process, the blower 42 can be stationary or moving, effectively removing powder from the surface under the action of the robotic arm 43.

[0084] Preferably, the robot 4 includes an electronic unit 65 to control the operation of the projector 41 and the blower 42, i.e., to control the supply and / or release of powder and fluid, for example, in a pre-programmed manner and / or manually. For this purpose, the electronic unit 65 specifically controls the projector head 61 and the blowing nozzle 81 and / or manifold 82, for example, via a set of solenoid valves. For example, the unit 65 includes an electronic controller connected via wires to the head 61, nozzle 81 and / or manifold 82, or other parts of the powder and fluid network supplying them, and connected via wires to a human-machine interface for human programming and control of the electronic controller.

[0085] like Figure 1 As shown, advantageously, the powder coating system includes an auxiliary blower 29, which differs from the blower 42 equipped with robots 4 and 6. The auxiliary blower 29 is preferably fixed, for example, supported on the inner wall by the floor 12, wall 16, or roof 14 of chamber 2. Like blower 42, the auxiliary blower 29 is provided for blowing powder removal fluid, preferably air. For example, the auxiliary blower 29 is identical to blower 42. This auxiliary blower 29 is used for powder removal from robot 4, particularly its projector 41, which can hardly remove powder by its own blower 42. To perform powder removal on robot 4, it is advantageous for its robotic arm 43 to position the projector 41 or any other surface of robot 4 from which powder is to be removed near the auxiliary blower 29, particularly in the path of the powder removal fluid flow. Thus, powder removal on robot 4, particularly on projector 41, is operated by the auxiliary blower 29. Powder removal on robot 6 can be operated in a similar manner for any other robot housed within chamber 2, particularly robot 6. The presence of the hair dryer 29 is particularly advantageous if room 2 includes a single robot such as robot 4, or if room 2 includes several robots, only one of which is equipped with hair dryer 42.

[0086] The above describes the case where the projector and hair dryer are permanently attached to the robotic arm. However, in a variation, it is possible to provide a portion, or even the entire hair dryer, and / or a portion, or even the entire projector, that can actually be detached from the robotic arm, preferably automatically.

[0087] Specifically, it is conceivable that the powder coating system includes a tool changing device 90, such as... Figure 1 The device 90 is shown schematically, for example, placed in room 2. It provides one or more spare tools for one or more robots. The device 90 is, for example, in the form of a rack with a corresponding slot for each spare tool, or a slot that alternates between several spare tools.

[0088] Specifically, the robotic arm 43 can approach the device 90 to automatically attach and detach the projector 41 and / or the blower 42 according to the operation to be performed. In this case, the projector 41 and / or the blower 42 are provided as backup tools that can be selectively equipped on the robotic arm 43. For example, during an electrostatic powdering operation, only the projector 41 is carried by the robotic arm 43, while the blower 42 is detached from the robotic arm 43 and carried by the device 90, awaiting further use. To perform a powder removal operation, the robotic arm 43 automatically attaches the blower 42 to the device 90 to carry the blower 42. To attach the blower 42, it is advantageously provided that the robotic arm 43 has pre-detached the projector 41 by placing it in the device 90. To perform electrostatic powdering, the robotic arm 43 automatically attaches the projector 41 to the device 90 to carry the projector 41. To equip the projector 41, it is advantageously provided that the robotic arm 43 has pre-detached the blower 42 by placing it in the device 90.

[0089] Any feature of one of the above embodiments or variations may be implemented in any other of the above embodiments or variations, provided that it is technically possible.

Claims

1. An electrostatic powder coating robot (4) for an electrostatic powder coating chamber (2), the electrostatic powder coating robot (4) comprising: Projector (41), the projector being configured to perform electrostatic powdering, characterized in that the electrostatic powdering robot (4) further includes: A robotic arm (43), hinged to and carrying the projector (41), is positioned within the electrostatic powder coating chamber (2) such that the projector (41) electrostatically powders the article (10) within the electrostatic powder coating chamber (2); and A blower (42) configured to blow powder removal fluid is provided. A robotic arm (43) carries the blower (42) to position it within an electrostatic powder coating chamber (2), such that the blower (42) blows the powder removal fluid onto the surface of the powder to be removed within the electrostatic powder coating chamber (2), thereby removing residual coating powder from the surface of the powder to be removed. in, The projector (41) includes a powdering electrode (64), and the electrostatic powdering includes raising the powdering electrode (64) to a powdering potential; and The electrostatic powdering robot (4) also includes a powder removal electrode (83) independent of the powdering electrode (64), which is configured to rise to an antistatic potential when the blower (42) blows the powder removal fluid onto the surface of the powder to be removed.

2. The electrostatic powder application robot (4) according to claim 1, wherein The robotic arm (43) includes a support head (46) that carries the projector (41) and the hair dryer (42), allowing the projector (41) and the hair dryer (42) to move together via the robotic arm (43).

3. The electrostatic powder application robot (4) according to claim 1 or 2, wherein The robotic arm (43) is a multi-joint arm configured to position the projector (41) and the blower (42) with at least five degrees of freedom.

4. The electrostatic powdering robot (4) according to claim 1 or 2, wherein: The projector (41) includes a first row (71) of electrostatic projection heads (61); and The blower (42) includes a row (91) of blowing nozzles (81) arranged parallel to the first row of electrostatic projection heads.

5. The electrostatic powder application robot (4) according to claim 4, wherein The projector (41) includes a second row (72) of electrostatic projectors (61) arranged parallel to the first row (71) of electrostatic projectors (61), and a row (91) of air nozzles (81) arranged between the first row (71) of electrostatic projectors (61) and the second row (72) of electrostatic projectors (61).

6. The electrostatic powdering robot according to claim 1 or 2, wherein the powder removal fluid is air.

7. An electrostatic powdering system, comprising: The electrostatic powdering robot (4) according to claim 1 or 2; and An electrostatic powder coating chamber (2) is provided, wherein the electrostatic powdering robot (4) is arranged such that the robotic arm (43) is capable of positioning the following components: The projector (41) inside the electrostatic powder coating chamber (2) electrostatically applies powder to the product (10) inside the electrostatic powder coating chamber (2); and The blower (42) inside the electrostatic powder coating chamber (2) is used to blow powder removal fluid onto the surface of the powder to be removed inside the electrostatic powder coating chamber (2).

8. The electrostatic powdering system according to claim 7, wherein: The electrostatic powdering system also includes another robot (6) arranged inside the electrostatic powder coating chamber (2); and The robotic arm (43) is configured to position the blower (42) such that the blower (42) can blow powder removal fluid onto the other robot (6) to remove powder from the other robot (6).

9. The electrostatic powdering system according to claim 7, wherein: The electrostatic powdering system also includes an auxiliary blower (29), which is located inside the electrostatic powder coating chamber (2) and is configured to blow powder removal fluid; and The robotic arm (43) is configured to position the projector (41) near the auxiliary blower (29) such that the auxiliary blower (29) blows powder removal fluid onto the projector (41) to remove powder from the projector (41).

10. The electrostatic powdering system according to claim 7, wherein: The hair dryer (42) is detachable from the robotic arm (43); The electrostatic powdering system includes a tool changing device (90) that is adapted to allow the blower (42) to be supplied to the robotic arm (43) when the blower (42) is removed from the robotic arm (43). and When the blower (42) is removed from the robotic arm (43) and made available to the robotic arm (43) via the tool changing device (90), the robotic arm (43) is adapted to automatically attach the blower (42) to the tool changing device (90) so as to carry the blower (42) to remove powder from the surface to be removed.

11. An electrostatic powdering method, performed by means of an electrostatic powdering robot (4) according to claim 1 or 2, the electrostatic powdering method comprising: Electrostatic powdering of the article (10) is performed by a projector (41), the projector (41) being positioned within the electrostatic powder coating chamber (2) by a robotic arm (43), wherein the electrostatic powdering includes raising the powdering electrode (64) to the powdering potential; and Once electrostatic powdering is performed, a blower (42) blows powder removal fluid onto the surface of the powder to be removed. The blower (42) is positioned by the robotic arm (43) within the electrostatic powder coating chamber (2) to remove residual coating powder from the surface of the powder to be removed. The powder removal electrode (83) rises to an antistatic potential while the blower (42) blows the powder removal fluid onto the surface of the powder to be removed.

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