Electrostatic coating equipment

Abstract

By preventing resin degradation and contamination without increasing the external dimensions of the electrostatic painting equipment, painting can be performed even in narrow or confined spaces, thereby improving painting efficiency. [Solution] The charge accumulated on the body 12 by the high-voltage discharge electrode 21, which discharges ions of the same polarity as the charged paint particles, can be discharged in the direction of grounding through the grounding metal part 23 provided on the arm mounting end 14A side of the neck part 14. As a result, the electrostatic painting apparatus 11 can prevent resin deterioration and soiling due to discharge without increasing the external dimensions of the body 12.

Description

Technical Field

[0001] The present invention relates to an electrostatic coating apparatus suitably used for coating an object to be coated such as an automobile body.

Background Art

[0002] When coating an object to be coated such as an automobile body, an electrostatic coating apparatus is used to improve the coating efficiency of the paint. This electrostatic coating apparatus applies a high voltage to the paint for coating. In addition, an electrostatic coating apparatus for coating an aqueous paint includes a body composed of a cylindrical body portion extending in the front-rear direction and a neck portion extending obliquely from the body portion, a coating machine provided on the body portion of the body for spraying the paint toward the object to be coated from the front paint spraying portion, and a high voltage applying mechanism for applying a high voltage to the paint sprayed from the paint spraying portion of the coating machine to form charged paint particles. A cartridge storing the paint supplied to the coating machine is detachably attached to the body portion of the body. Further, the body is formed of an insulating resin material so that the high voltage applied to the paint does not leak. And the electrostatic coating apparatus has the neck portion of the body attached to the tip of the arm of the coating robot.

[0003] During coating by the electrostatic coating apparatus, some of the sprayed paint particles may become floating paint particles and adhere to the surface of the body. Therefore, some electrostatic coating apparatuses have measures to prevent contamination using corona discharge in order to prevent the floating paint particles from adhering and soiling the body. This electrostatic coating apparatus is provided with a high voltage discharge electrode on the outer peripheral side of the body portion of the body, and discharges ions of the same polarity as the charged paint particles from the high voltage discharge electrode. Specifically, the high voltage discharge electrode arranges a ring (hereinafter referred to as a corona ring) having a plurality of thorn shapes or portions with a small radius of curvature that enhance electric field concentration and promote corona discharge in the high voltage portion, thereby charging the surface of the insulating portion of the body and the floating paint particles, and increasing the Coulomb repulsive force between the charged paint particles and the surface of the insulating portion to prevent soiling of the body (Patent Documents 1, 2).

[0004] Here, if the dielectric strength between the charged insulating surface and the grounding metal connected to the painting robot's arm falls below the potential difference due to the saturated charge on the insulating surface, repeated charging and discharging will occur between the insulating surface and the grounding metal, potentially damaging the resin at their boundary. Generally, since the resin component with an insulating surface and the grounding metal are simply joined together, if a large amount of airborne paint particles adhere to the surface of the resin component, the insulation becomes insufficient, and consequently, charging and discharging increase. As a result, the charging of the insulating surface by corona ring increases per unit time. On the other hand, the amount of charge that naturally dissipates into the air depends on the surface potential, and consequently, the amount of charge on the insulating surface increases, raising the surface potential. This increases Joule loss during discharge, accelerating the deterioration of the resin component in a short time.

[0005] Therefore, a film is prepared that uniformly maintains the static charge throughout and ensures sufficient insulation, and a cover member is formed using this film. By covering the boundary area with this cover member in a non-contact manner, dirt is reliably prevented while preventing resin degradation. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Patent No. 4745934 [Patent Document 2] Patent No. 4733133 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, because the cover component is designed to cover the protective part in a non-contact manner, it increases the external dimensions of the painting equipment, which presents a problem as it makes it difficult to use for painting in narrow or confined spaces.

[0008] Furthermore, in recent automotive painting operations, it is becoming common practice to improve painting efficiency by painting both the exterior and interior panels of the vehicle body with a single painting machine. However, painting machines equipped with cover components are not suitable for painting narrow interior panels, and therefore cannot improve painting efficiency.

[0009] The present invention has been made in view of the problems of the prior art described above, and the object of the present invention is to provide an electrostatic coating apparatus that can prevent resin degradation and contamination without increasing the external dimensions, thereby improving coating efficiency. [Means for solving the problem]

[0010] The present invention relates to an electrostatic painting apparatus comprising: a body made of an insulating resin material, comprising a cylindrical body portion extending in the front-rear direction and a neck portion extending diagonally from the body portion, the neck portion being attached to the tip of the arm of a painting robot; a painting machine provided on the body portion of the body, which sprays paint from a front paint spraying section toward an object to be painted; a high-voltage application mechanism that applies a high voltage to the paint sprayed from the paint spraying section of the painting machine to form charged paint particles; and a high-voltage discharge electrode provided on the outer circumference of the body portion of the body, which discharges ions of the same polarity as the charged paint particles, wherein the charge accumulated on the body by the high-voltage discharge electrode flows toward ground through a grounding metal portion provided on the arm attachment end of the neck portion. Furthermore, the neck portion of the body is attached to the tip of the arm of the painting robot using a conductive metal plate, and the grounding metal portion is positioned closer to the high-voltage discharge electrode than the metal plate in terms of creepage distance along the surface of the body, or in a position where the electrical path has lower resistance when the surface of the body is contaminated with paint. It is characterized by the following: Furthermore, the present invention relates to an electrostatic painting apparatus comprising: a body made of an insulating resin material, comprising a cylindrical body portion extending in the front-rear direction and a neck portion extending diagonally from the body portion, the neck portion being attached to the tip of the arm of a painting robot; a painting machine provided on the body portion of the body, which sprays paint from a front paint spraying section toward an object to be painted; a high-voltage application mechanism that applies a high voltage to the paint sprayed from the paint spraying section of the painting machine to form charged paint particles; and a high-voltage discharge electrode provided on the outer circumference of the body portion of the body, which discharges ions of the same polarity as the charged paint particles, wherein the neck portion of the body is provided with a semiconducting cover that covers the arm attachment end and whose surface is covered with a semiconducting coating or made of a semiconducting resin material. [Effects of the Invention]

[0011] According to the present invention, the electrostatic coating apparatus can prevent resin degradation and contamination without increasing its external dimensions, allowing coating to be performed even in narrow or confined spaces, thereby improving coating efficiency. [Brief explanation of the drawing]

[0012] [Figure 1] This is an overall configuration diagram showing the electrostatic painting apparatus according to the first embodiment of the present invention attached to a painting robot. [Figure 2] This is a front view showing an electrostatic coating apparatus according to the first embodiment. [Figure 3] This is a front view showing an electrostatic coating apparatus according to a second embodiment. [Figure 4] This is a front view showing an electrostatic coating apparatus according to a third embodiment. [Modes for carrying out the invention]

[0013] Hereinafter, an electrostatic coating apparatus according to an embodiment of the present invention will be described in detail with reference to the attached drawings, using an electrostatic coating apparatus equipped with a rotary atomizing head type coating machine as an example. The electrostatic coating apparatus can also be applied to those equipped with other coating machines such as air atomizing type and hydraulic atomizing type.

[0014] In Figure 1, the painting robot 1 is a robotic device for automatically performing painting work according to programmed movements. The painting robot 1 moves the electrostatic painting device 11, described later, along a path that follows the shape of the object to be painted (not shown). The painting robot 1 is composed of a base 2, a first arm 3 mounted on the base 2 so as to be rotatable about a vertically extending axis as the centerline and so as to be rotatable in a direction inclined with respect to the centerline, and a second arm 4 as an arm rotatably mounted at the tip of the first arm 3.

[0015] The tip of the second arm 4 is provided with a multi-joint section 4A consisting of multiple rotating parts. An electrostatic coating device 11 is attached to the tip of this multi-joint section 4A, which constitutes the tip of the second arm 4, using a metal plate 15, which will be described later. The multi-joint section 4A of the second arm 4 is connected to earth (grounded) together with the metal plate 15.

[0016] Next, the configuration, functions, etc., of the electrostatic coating apparatus 11, which is a characteristic feature of this embodiment, will be described in detail.

[0017] The electrostatic coating apparatus 11 according to the first embodiment is configured as a direct-charging type electrostatic coating apparatus that directly applies a high voltage to the paint to be sprayed. The electrostatic coating apparatus 11 is attached to the tip of the second arm 4 of the painting robot 1. The electrostatic coating apparatus 11 consists of a body 12, a painting machine 16, a high-voltage application mechanism 20, a high-voltage discharge electrode 21, a resin cover 22, and a grounding metal part 23, which will be described later. In the description of the configuration of the electrostatic coating apparatus 11, the direction of paint spraying will be referred to as the front, and the side opposite to the spraying direction will be referred to as the rear.

[0018] The body 12 is attached to the tip of the second arm 4 of the painting robot 1. The body 12 is formed of an insulating resin material such as POM (polyoxymethylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), HP-PE (high-pressure polyethylene), HP-PVC (high-pressure vinyl chloride), PEI (polyetherimide), PES (polyethersulfone), polymethylpentene, etc. The body 12 includes a body portion 13 and a neck portion 14.

[0019] The body portion 13 is formed in a cylindrical shape extending in the front-rear direction. A painting machine 16 is provided on the front side of the body portion 13, and a cartridge 19 described later is attached to the rear side of the body portion 13 in a replaceable manner.

[0020] The neck portion 14 is formed to extend obliquely rearward from the outer periphery of the body portion 13 so as to branch from the body portion 13. The neck portion 14 has a large-diameter arm attachment end 14A on the side opposite to the body portion 13 in the length direction. This arm attachment end 14A is attached to the tip of the second arm 4 of the painting robot 1, that is, the tip of the articulated portion 4A. The arm attachment end 14A and the tip of the articulated portion 4A are connected using a conductive metal plate 15, a screw member (not shown), etc. Inside the neck portion 14, a high-voltage generator 20A of the high-voltage application mechanism 20 is accommodated. Also, inside the neck portion 14, a flow path through which paint, cleaning liquid, and air flow, wiring, etc. are provided.

[0021] The neck portion 14 is integrally attached to the tip of the articulated portion 4A, for example, by fixing the metal plate 15 with a screw member in a state where the arm attachment end 14A faces the tip of the articulated portion 4A. Thereby, the metal plate 15 is grounded through the arms 4, 3 and the base 2 of the painting robot 1.

[0022] The surface 13A of the body portion 13 and the surface 14B of the neck portion 14 of the body 12 are charged by corona discharge from the high-voltage discharge electrode 21 described later. This prevents soiling due to the Coulomb repulsion force between the sprayed charged paint particles and the charged surface 13A of the body portion 13 and the surface 14B of the neck portion 14.

[0023] The painting machine 16 is installed in the fuselage 13 of the body 12. The painting machine 16 is configured as a cartridge-type painting machine that sprays paint supplied from a cartridge 19, which will be described later. The painting machine 16 is installed on the front side inside the fuselage 13 and includes an air motor 17 that rotates a rotating shaft (not shown) extending in the front-rear direction at high speed using compressed air, a rotating atomizing head 18 which is located on the front side of the fuselage 13 and attached to the rotating shaft of the air motor 17 and serves as a paint spraying unit that sprays the supplied paint by centrifugal force, and a cartridge 19 which is detachably attached to the rear side of the fuselage 13 and supplies paint toward the rotating atomizing head 18.

[0024] The cartridge 19, when attached to the body 13, is equipped with a feed tube 19A whose tip reaches the rotating atomizing head 18. The feed tube 19A discharges paint toward the rotating atomizing head 18 and is in communication with the paint filling chamber inside the cartridge 19 via a supply valve (neither of which is shown).

[0025] The high-voltage application mechanism 20 applies a high voltage to the paint sprayed from the rotating atomizing head 18 of the painting machine 16 to create charged paint particles. The high-voltage application mechanism 20 is composed of, for example, a high-voltage generator 20A built into the neck section 14 and a high-voltage cable 20B that electrically connects the high-voltage generator 20A to the air motor 17.

[0026] The high-voltage generator 20A is composed of a multi-stage rectifier circuit (a so-called Cockcroft circuit) consisting of, for example, multiple capacitors and diodes (none of which are shown). The high-voltage generator 20A boosts the DC power supply voltage supplied from a high-voltage control device (not shown) to generate a high voltage of, for example, -30 to -150kV. As a result, the high-voltage application mechanism 20 can directly apply the high voltage boosted by the high-voltage generator 20A to the paint sprayed from the rotating atomizing head 18 via the high-voltage cable 20B, air motor 17, etc.

[0027] The high-voltage discharge electrode 21 is provided on the outer circumference of the body portion 13 of the body 12. The high-voltage discharge electrode 21 consists of, for example, a plurality of spike-like bodies that protrude radially from the front side of the body portion 13. The high-voltage discharge electrode 21 discharges ions of the same polarity as the charged paint particles. As a result, the high-voltage discharge electrode 21 is subjected to a high voltage by the high-voltage application mechanism 20, and discharges ions of the same polarity as the charged paint particles from the plurality of spike-like bodies. In addition to spike-like bodies, the high-voltage discharge electrode 21 may also be formed as a ring-shaped body having a plurality of parts with a small radius of curvature.

[0028] The resin cover 22 is provided on the neck portion 14 of the body 12. The resin cover 22 is formed as a thin cylindrical body that tightly covers the arm mounting end 14A side of the neck portion 14. The resin cover 22 has a thickness dimension such that resin deterioration does not immediately cause problems, for example, a thickness dimension of 5 mm to 20 mm. Also, the resin cover 22 is a part that does not have any functionality such as sealing. A grounding metal portion 23 is provided around the resin cover 22. The resin cover 22 can be replaced if it deteriorates.

[0029] The grounding metal part 23 is provided around the resin cover 22. The grounding metal part 23 is conductive and allows the charge accumulated on the body 12 by the high-voltage discharge electrode 21 to flow in the direction of grounding. The grounding metal part 23 is positioned closer to the high-voltage discharge electrode 21 than the metal plate 15, based on the creepage distance along the surface 13A of the body portion 13 and the surface 14B of the neck portion 14 that constitute the body 12. In other words, the grounding metal part 23 is provided around the arm mounting end 14A of the neck portion 14, closer to the body portion 13 than the metal plate 15. The grounding metal part 23 may also be positioned in a location where the electrical path has lower resistance when the surface of the body 12 (surface 13A of the body portion 13 and surface 14B of the neck portion 14) is contaminated with paint.

[0030] The grounding metal part 23 consists of an annular body extending around the resin cover 22 and is grounded via the painting robot 1. Therefore, the grounding metal part 23 can actively direct the charge accumulated on the body 12 toward grounding. As a result, the grounding metal part 23 can reduce soiling of the body 12 while avoiding the need for a larger cover member. The annular body may include a continuous ring shape, a coil shape, or a C-shape with a portion interrupted.

[0031] The electrostatic painting apparatus 11 according to the first embodiment has the configuration described above, and next, the operation of the electrostatic painting apparatus 11 together with the painting robot 1 will be explained.

[0032] When an object to be painted is placed near the painting robot 1 using a conveyor system (not shown), the painting robot 1 operates based on pre-stored teaching movements and moves the electrostatic painting device 11 along the shape of the object to be painted.

[0033] At this time, the painting machine 16 rotates the rotating atomizing head 18 at high speed using the air motor 17, and in this state, supplies the paint in the cartridge 19 to the rotating atomizing head 18 through the feed tube 19A. As a result, the painting machine 16 atomizes the paint into fine particles using the centrifugal force generated when the rotating atomizing head 18 rotates, and sprays them as paint particles.

[0034] Furthermore, a high voltage is applied to the rotating atomizing head 18 via the air motor 17 by the high voltage application mechanism 20 (high voltage generator 20A). As a result, the paint supplied to the rotating atomizing head 18 is directly charged to a high voltage through the rotating atomizing head 18, and as charged paint particles, it flies along the electrostatic field formed between the rotating atomizing head 18 and the object to be painted, and adheres to the object to be painted, which is at ground potential.

[0035] Furthermore, in this embodiment, a high-voltage discharge electrode 21 is provided on the outer circumference of the body portion 13. Therefore, the high voltage from the high-voltage application mechanism 20 is applied to the high-voltage discharge electrode 21 via the air motor 17 or the like, and discharge occurs from the high-voltage discharge electrode 21.

[0036] Therefore, the high-voltage discharge electrode 21 discharges ions of the same polarity as the charged paint particles, actively charging the surface 13A of the body portion 13 and the surface 14B of the neck portion 14 that constitute the body 12 with charges of the same polarity. This allows a repulsive force to act between the charged paint particles and the high-voltage discharge electrode 21 or the body 12, thereby suppressing the adhesion of paint particles to the surface 13A of the body portion 13 and the surface 14B of the neck portion 14.

[0037] Here, when the surface of the body 12 is clean, sufficient creepage distance is ensured, so the charges accumulated on the surface 13A of the body 13 and the surface 14B of the neck 14 do not easily move. On the other hand, when charged paint particles adhere to the surface of the body 12, areas with locally low insulation resistance become unevenly distributed across the entire surface, and the charged electricity begins to move toward these areas with low insulation resistance. This movement of charge disrupts the electric field and promotes further charge movement. In other words, when the surface of the body 12 becomes dirty, the charged electricity dispersed on the surface of the body 12 accumulates and moves to the nearest ground point.

[0038] Furthermore, if the charged surface accumulates in one area, the surface potential increases, and the Joule loss during discharge increases, which may accelerate the deterioration of the resin component in a short time. For this reason, it is necessary to cover the body 12 with a cover component made of a film that uniformly holds the charged surface and ensures sufficient insulation. In this case, the external dimensions will increase due to the cover component, making painting difficult in narrow or intricate spaces.

[0039] However, according to this embodiment, the charge accumulated on the body 12 by the high-voltage discharge electrode 21 that discharges ions of the same polarity as the charged paint particles can be flowed in the direction of grounding through the grounding metal part 23 provided on the arm mounting end 14A side of the neck part 14.

[0040] As a result, the electrostatic coating apparatus 11 can prevent resin degradation and contamination due to discharge without increasing the external dimensions of the body 12. Consequently, the electrostatic coating apparatus 11 can perform coating even in narrow or intricate spaces, improving coating efficiency.

[0041] Furthermore, the neck portion 14 of the body 12 is attached to the tip of the second arm 4 of the painting robot 1 using a conductive metal plate 15, and the grounding metal portion 23 is positioned closer to the high-voltage discharge electrode 21 than the metal plate 15 in terms of creepage distance along the surface 13A of the torso portion 13 of the body 12 and the surface 14B of the neck portion 14. Alternatively, the grounding metal portion 23 is positioned so that the electrical path has lower resistance when the surface 13A of the torso portion 13 of the body 12 and the surface 14B of the neck portion 14 are contaminated with paint. This allows the charge accumulated on the body 12 to flow efficiently towards ground through the grounding metal portion 23.

[0042] Furthermore, the neck portion 14 of the body 12 is provided with a resin cover 22 that covers the arm mounting end 14A side, and the grounding metal portion 23 is formed as an annular body that extends around the resin cover 22. As a result, even if the resin cover 22 deteriorates due to discharge of the grounding metal portion 23, it can be easily replaced with a new resin cover 22.

[0043] Next, Figure 3 shows a second embodiment of the present invention. The feature of the second embodiment is that a replaceable resin annular member is provided between the resin cover and the grounding metal part. In the second embodiment, the same reference numerals are used for the same components as in the first embodiment described above, and their descriptions are omitted.

[0044] In Figure 3, the electrostatic coating apparatus 31 according to the second embodiment is configured similarly to the electrostatic coating apparatus 11 according to the first embodiment, including a body 12, a coating machine 16, a high-voltage application mechanism 20, a high-voltage discharge electrode 21, a resin cover 22, and a grounding metal part 23. However, the electrostatic coating apparatus 31 according to the second embodiment differs from the electrostatic coating apparatus 11 according to the first embodiment in that a resin annular member 32, described later, is provided between the resin cover 22 and the grounding metal part 23.

[0045] The resin annular member 32 is provided between the resin cover 22 and the grounding metal part 23. The resin annular member 32 is designed as a replaceable consumable part (inexpensive component) that can be replaced when it deteriorates due to high-voltage discharge. The resin annular member 32 is provided on the outer circumference of the resin cover 22 so as to surround the resin cover 22. The resin annular member 32 is formed as an annular strip that includes a continuous circular shape around its entire circumference and a C-shape with a portion interrupted.

[0046] Furthermore, an annular groove 32A is formed around the entire circumference of the resin annular member 32. As a result, the resin annular member 32 has a C-shaped cross-section that opens outwards. The grounding metal part 23 is detachably fitted into the annular groove 32A.

[0047] The resin annular member 32, like the grounding metal part 23, is positioned closer to the high-voltage discharge electrode 21 than the metal plate 15, based on the creepage distance along the surface 13A of the body portion 13 and the surface 14B of the neck portion 14 that constitute the body 12. In other words, the resin annular member 32 is provided around the arm mounting end 14A of the neck portion 14, closer to the body portion 13 than the metal plate 15.

[0048] Thus, the same functions and effects as in the first embodiment can be obtained in the second embodiment configured in this way. In particular, in the second embodiment, a replaceable resin annular member 32 is provided between the resin cover 22 and the grounding metal part 23. This protects the resin cover 22 by causing deterioration of the resin annular member 32 due to discharge. In other words, by making the resin annular member 32, which is cheaper and easier to replace than the resin cover 22, a disposable part, it is possible to reduce costs and improve productivity (work efficiency).

[0049] Next, Figure 4 shows a third embodiment of the present invention. The characteristic of the third embodiment is that the neck portion of the body is provided with a semiconductive cover that covers the arm mounting end and whose surface is covered with a semiconductive coating or made of a semiconductive resin material. In the third embodiment, the same reference numerals are used for the same components as in the first embodiment described above, and their descriptions are omitted.

[0050] In Figure 4, the electrostatic coating apparatus 41 according to the third embodiment is configured similarly to the electrostatic coating apparatus 11 according to the first embodiment, including a body 12, a coating machine 16, a high-voltage application mechanism 20, and a high-voltage discharge electrode 21. However, the electrostatic coating apparatus 41 according to the third embodiment differs from the electrostatic coating apparatus 11 according to the first embodiment in that a semiconducting cover 42 is provided instead of a resin cover 22.

[0051] The semiconductive cover 42 according to the third embodiment is formed as a thin-walled cylindrical body that closely covers the arm mounting end 14A side of the neck portion 14, similar to the resin cover 22 according to the first embodiment. However, the semiconductive cover 42 differs from the resin cover 22 according to the first embodiment in that its outer surface is covered with a semiconductive coating, or the entire structure is made of a semiconductive resin material. When the semiconductive cover 42 deteriorates, the coating is repaired by repainting, or it is replaced as a disposable part (consumable).

[0052] Thus, the same functions and effects as in the first embodiment can be obtained in the third embodiment configured in this way. In particular, in the third embodiment, the neck portion 14 of the body 12 is provided with a semiconductive cover 42 that covers the arm mounting end 14A side and whose surface is covered with a semiconductive coating or made of a semiconductive resin material. As a result, if the semiconductive cover 42 deteriorates due to discharge, it can be reused by repairing the coating by repainting, or it can be replaced as a disposable part (consumable).

[0053] In the first embodiment, a cartridge-type electrostatic coating apparatus 11, which supplies paint from a detachable cartridge 19 to a rotating atomizing head 18, was described as an example of an electrostatic coating apparatus. However, the present invention is not limited to this, and may be applied to an electrostatic coating apparatus that supplies paint from a paint supply source to a rotating atomizing head through piping, for example. This configuration can also be applied to other embodiments. [Explanation of Symbols]

[0054] 1. Painting robot 4. Second Arm (Arm) 11,31,41 Electrostatic coating equipment 12 Body 13 Torso 13A,14B surface 14. Neck section 14A Arm mounting end 15 Metal Plate 16 Painting machine 18 Rotating atomization head (paint spraying part) 20 High-voltage application mechanism 21 High-voltage discharge electrodes 22 Plastic cover 23 Ground metal part 32. Resin annular member 42 Semiconductive cover

Claims

1. The body consists of a cylindrical torso extending in the front-to-back direction and a neck extending diagonally from the torso, the neck being made of an insulating resin material and attached to the tip of the arm of a painting robot. A painting machine provided on the torso of the body, which sprays paint from the front paint spraying section toward the object to be painted, A high-voltage application mechanism that applies a high voltage to the paint sprayed from the paint spraying section of the painting machine to form charged paint particles, A high-voltage discharge electrode is provided on the outer circumference of the body portion of the aforementioned body, which discharges ions of the same polarity as the charged paint particles, In an electrostatic coating apparatus equipped with, The charge accumulated on the body by the high-voltage discharge electrode is discharged in the direction of grounding through the grounding metal portion provided on the arm mounting end side of the neck portion. The neck portion of the body is attached to the tip of the arm of the painting robot using a conductive metal plate. The electrostatic coating apparatus is characterized in that the grounding metal part is positioned closer to the high-voltage discharge electrode than the metal plate in terms of creepage distance along the surface of the body, or in a position where the electrical path becomes less resistive when the surface of the body is contaminated with paint.

2. In the electrostatic coating apparatus according to claim 1, The neck portion of the body is provided with a resin cover that covers the arm mounting end. The electrostatic coating apparatus is characterized in that the grounding metal part is formed as an annular body extending around the periphery of the resin cover.

3. In the electrostatic coating apparatus according to claim 2, An electrostatic coating apparatus characterized in that a replaceable resin annular member is provided between the resin cover and the grounding metal part.

4. The body consists of a cylindrical torso extending in the front-to-back direction and a neck extending diagonally from the torso, the neck being made of an insulating resin material and attached to the tip of the arm of a painting robot. A painting machine provided on the torso of the body, which sprays paint from the front paint spraying section toward the object to be painted, A high-voltage application mechanism that applies a high voltage to the paint sprayed from the paint spraying section of the painting machine to form charged paint particles, A high-voltage discharge electrode is provided on the outer circumference of the body portion of the aforementioned body, which discharges ions of the same polarity as the charged paint particles, In an electrostatic coating apparatus equipped with, An electrostatic coating apparatus characterized in that the neck portion of the body is provided with a semiconductive cover that covers the arm mounting end and whose surface is covered with a semiconductive coating or made of a semiconductive resin material.

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