JPH08257441A - Rotary atomization type electrostaic spray coating device - Google Patents

Abstract

PURPOSE: To maintain charge acceptance, coating quality and work safety and to simplify cleaning work with small-sized and lightweight equipment by closing a clearance between a feed cable and a connecting hole and a clearance between a base end part of a grid electrode element and a fitting hole with an insulating material to prevent high voltage leak from the clearances. CONSTITUTION: Each grid electrode element 1 is arranged, outward opened and inclined by using each fitting hole 15 inclined outward on a tip surface side 13 of an electrode supporting body 11 so that a region from a base end part 42B to a tip part 44 can be in the outside centering a rotating axis line 9 of a bell 3. A feed cable 4 inserted into a connecting hole 14 on a rear end surface side 12 of the electrode supporting body 11 and a terminal part 43T of each grid electrode element 41 inserted into a fitting hole 15 are connected through a ring-shaped conductor 21 embedded in the electrode supporting body 11 so as to be fed. A clearance between the feed cable 4 and the connecting hole 14 and a clearance between the base end part 42B of the grid electrode element 41 and each fitting hole 15 are closed by stress cones 31, 32 as an insulating material respectively to prevent high voltage leak to the outside through each clearance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bell rotatably mounted on a bell support, and a plurality of grid electrodes mounted on an electrode support integral with the bell support in a separated state on a virtual circle locus. The present invention relates to a rotary atomization type electrostatic coating machine, which is equipped with an element and electrostatically coats an object to be coated with the atomized paint using a rotation of a bell while using each grid electrode element to charge the same.

[0002]

2. Description of the Related Art The basic structure of a rotary atomizing electrostatic coating machine is
It comprises a bell rotatably mounted on a bell support, and a charging means for directly or indirectly charging the atomized paint by utilizing the rotation of the bell.

4 and 6, the bell 3 is attached to the tip (right side in FIG. 6) of a hollow shaft 8 rotatably supported about an axis 9 by an air bearing 8A in the bell support 2. An air turbine 8B is attached to the rear end side (left side) of the hollow shaft 8. A paint supply pipe 6 for supplying the paint P to the bell 3 is inserted into the hollow shaft 8 in a non-contact manner. Thus, if the paint P is supplied through the paint supply pipe 6 while the bell 3 is rotationally driven by the air turbine 8B at a high speed of, for example, 6,000 to 20,000 RPM, the paint P is atomized by the rotation of the bell 3 and is shown in FIG. The atomization pattern PTN having a diameter DMP centered on the rotation axis (center) of the bell 3 shown, that is, the axis 9 is formed.

The paints P include organic solvent paints using thinner as a solvent and water-based (water-soluble, water-based) paints P2 using water as a solvent or solvent. The organic solvent-based paint is rich in electrical insulation, and the water-based paint P2 is highly conductive. Therefore, when the organic solvent-based paint is used, the charging means may be a direct charging system in which the bell 3 is directly charged to negatively charge the paint, but in the case of the water-based paint P2, the paint supply pipe 6 is grounded. Therefore, the direct charging method cannot be adopted.

Therefore, when the water-based paint P2 is used, the charging means is a plurality of grid electrode elements 41 shown in FIGS.
It is composed of a grid electrode device including A. That is,
Atomization paint (P2) of the atomization pattern PTN shown in FIG.
This is a grid electrode charging method in which each grid electrode element 41A (44) is indirectly charged to be negatively charged.

As shown in FIG. 5, each grid electrode element 41A comprises an insulating cylindrical body 42, a current limiting resistor 43 and a discharge pin (tip portion) 44, and an electrode support 11A via a base end portion.
It is attached to the tip side (right side) side of. Specifically, the electrode support 11A has a cylindrical shape or a disk shape with a hole in which the hollow portion can be fitted in the bell support 2, and is integrally attached to the bell support 2. A plurality (for example, six) of grid electrode elements 41A are mounted in a separated state (equal spacing) on a virtual circle locus of diameter DM1 with the axis 9 of the electrode support 11A as the center.

The rear end surface (left surface) of the electrode support 11A
Each power feeding cable 4 inserted from the side is connected so that power can be fed using the corresponding grid electrode element 41A (current limiting resistor 43) and the conductive material K, and each grid electrode element 41A
A high voltage (for example, -40 to -80 KV) can be applied to. The current limiting resistor 43 may be provided, for example, between each power feeding cable 4 and a power supply device (not shown) without being provided in each grid electrode element 41A, but the function thereof does not change.

Here, the rear end of the bell support 2 and the bell 3
Is grounded (on the positive electrode side) like the paint supply pipe 6 and the object to be coated (not shown). Therefore, the joint (K)
It is necessary to prevent high voltage leakage from the outside to the outside, that is, the side of the bell support 2. For this purpose, the mounting portion between the insulating cylindrical body 42 forming each grid electrode element 41A and the tip end surface side of the electrode support 11A is, for example, adhesively sealed using the electrical insulating material J, and the power supply cable 4 is attached to the rear end surface side. Is provided with a protective cylinder 7 having a high electrical insulation property that can be fitted in a non-contact manner, and a connecting portion between the protective cylinder 7 and the rear end face side is electrically insulating material J.
Is used for adhesive sealing.

Assuming that the length of the protective cylinder 7 is L and the distance between the protective cylinder 7 and the bell support 2 is D, D can be decreased by increasing L, and D must be increased by decreasing L.
The applied voltage of each grid electrode element 41A is, for example, −80K.
In the case of V, the distance D needs to be, for example, 250 to 300 mm or more.

The diameter DMP of the atomized pattern PTN of the water-based paint P2 shown in FIG. 4 is, for example, 400 to 600 mm as the effective coating diameter. Thus, each discharge pin 4
The diameter DM2 of the virtual circle locus on which 4 is located is substantially equal to DMP (for example, 650 mm). Also, DM2 = DM1
Is. That is, as shown in FIGS. 4 and 5, each grid electrode element 41A and each corresponding power supply cable 4 are perpendicular to the front end surface and the rear end surface of the electrode support 11A, that is, parallel to the axis 9. It is arranged.

In such a conventional rotary atomizing electrostatic coating machine 1A, for example, −80 KV is applied (powered) from each power feeding cable 4 to each grid electrode element 41A, and the paint supply pipe 6 is fed to the bell 3 which is rotating at high speed. When the water-based paint P2 is supplied through the water-based paint P2, the water-based paint P2 has a size (DMP) shown in FIG.
Is atomized with the atomization pattern PTN, and is charged and negatively charged from each discharge pin 44. Therefore, the object to be coated on the positive electrode side (earth) can be electrostatically coated.

[0012]

From the viewpoint of VOC regulation, the water-based water-based paint P2 has attracted attention and its practical application has been further promoted, and it is strongly desired to solve the following problems. ing.

The tip portion (the discharge pin 44 and the insulating cylindrical body 42) of each grid electrode element 41A is separated from the atomized paint (P2) in the atomization pattern PNT in the left direction in FIG. Even with this, the tip (44, 4)
The paint (P2) adheres to 2) and becomes dirty. If this is left for a long time, the solidified paint (P2) is pulled by electrostatic attraction and adheres to the object to be coated. That is, the lumps cause the coating quality to deteriorate.

In order to solve the above, it is necessary to interrupt the coating operation and clean each grid electrode element 41A (44, 42). Moreover, since this cleaning work has to be done every short time (for example, several hours), not only is it troublesome and difficult to handle, but the production efficiency is reduced.

If the distance D shown in FIG. 5 is increased to, for example, 250 mm or more in order to further ensure high-voltage leakage, the electrode support 11A must inevitably have a larger diameter (for example, DM1 = 650 mm or more). I won't.
Then, since the electrode support 11A becomes an obstacle, the rightward wind in FIG. 4 generated due to the high speed rotation of the bell 3 is disturbed, and a violent turbulent flow occurs on the downstream side of the electrode support 11A. Therefore, each grid electrode element 41A (44, 4
2) Paint (P2) not only on the tip of the bell support 2
Are easily adhered, and the above problem or is further increased.

As the distance D, that is, the diameter DM1 (DM2) of the virtual circle locus is increased to prevent high voltage leakage, the electrode support 11A becomes larger in space and weight. Therefore, the automation of coating performed by supporting the bell 3 (bell support 2) on the robot arm is hindered.
In other words, the size of the robot increases due to the increased load, the cost increases,
This leads to narrowing of the moving range and slowing down of the moving speed. In addition, the wiring process of the high voltage power supply cables 4 as many as the number of grid electrode elements 41A is complicated, and each of the high-rigidity holding cylinders 7 also becomes a hindrance, which is a further impediment to automation of coating. In addition, there is a problem that the spacing between the coating machines in rows becomes large.

When the electrode support 11A is reduced in size and weight (the diameter of DM1 is reduced) within the allowable range for prevention of high-voltage leakage on the side of the power supply cable 4 for the above-described automation of coating, the discharge pins 44 and The distance (relative position) to the bell 3 and the relative position (DMP) of each discharge pin 44 and the atomization pattern PTN in the radial direction with the axis 9 as the center.
And DM2) cannot be maintained in an ideal state. That is, there is a possibility that a high voltage leak or a short circuit may occur between each discharge pin 44 and the bell 3, and the charging efficiency will decrease.

[0018] A larger length of the protective cylinder is limited in terms of space and cost. Therefore, if the diameter of the electrode support is increased in order to prevent high voltage leakage, the high voltage range for an operator is expanded. Moreover, there are many power cables. Therefore, the safety of the worker is impaired.

An object of the present invention is to provide a rotary atomizing type electrostatic coating machine which is small in size and lightweight, which simplifies cleaning work and facilitates coating automation while ensuring desired charging efficiency, coating quality and work safety. It is in.

[0020]

SUMMARY OF THE INVENTION According to the present invention, a bell rotatably mounted on a bell support and a plurality of electrode supports integrated with the bell support are mounted in a separated state on a virtual circle locus. A rotary atomization type electrostatic coating machine comprising a grid electrode element and electrostatically coating an object to be coated while charging the atomized paint using the rotation of a bell using each grid electrode element, Each grid electrode element is provided on the tip end surface side of the electrode support, and the tip end portion is located outside the base end portion about the rotation axis of the bell by using the mounting holes inclined outward. The electrode is provided so as to be inclined outward and the power supply cable fitted in one connection hole provided on the rear end face side of the electrode support and the terminal portion of each grid electrode element fitted in each mounting hole Each is supplied via a ring-shaped conductor embedded in the support. Connection between the power supply cable and the connection hole, and the gap between the base end of each inserted grid electrode element and each of the mounting holes are covered with an electrical insulating material. It is characterized in that it is formed so as to prevent high voltage leakage to the outside.

In the above invention, the gap between the power feed cable and the connection hole and the gap between the base end of each grid electrode element and each mounting hole are covered with an electric insulating material, so that the power feed cable and the ring are closed. It is possible to reliably prevent a high-voltage leak from the linear conductor to the bell support or the like (the outside). Therefore, the diameter of the electrode support can be reduced, the size and weight of the electrode support can be significantly reduced, and the turbulence of the wind due to the rotation of the bell can be reduced, so that the amount of paint adhered to each grid electrode element or the like can be reduced. Further, the cleaning work can be simplified and the production efficiency can be improved. In addition, since only one power supply cable is required and the long and high-rigidity protection tube of the conventional example can be wiped out, it is easy to automate the coating in combination with the reduction in size and weight of the electrode support itself, and its function improvement and cost reduction. Can be reduced.

On the other hand, the base end portion of each grid electrode element is supported by using each mounting hole of the electrode support body having a reduced diameter, and the tip end portion thereof is centered on the rotation axis of the bell rather than the base end portion. The grid electrode elements are arranged so as to be outwardly inclined so as to be outside. The degree of inclination can be appropriately selected depending on the outward inclination angle of each mounting hole. Therefore, it is possible to set the relative position between the tip of each grid electrode element and the bell and the relative position between each grid electrode element and the atomization pattern of the paint in an ideal state. It is possible to reliably prevent high voltage leakage between them and significantly improve the charging efficiency.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. This rotary atomization type electrostatic coating machine (1)
As shown in FIGS. 1 to 3, each grid electrode element 41 is centered on the axis 9 and is more distal than the proximal end (42B) (44).
Is outwardly inclined so as to be on the outer side, and the power supply cable 4 and the ring-shaped conductor 21 and the electrode support 11 of the ring-shaped conductor 21 and each grid electrode element 41 (43T) are arranged. The connection portion is electrically insulated from the outside (2, 11) by using the electrical insulating materials 31 and 32. The axis 9 is the rotation axis (center) of the bell 3, but in this embodiment, the axis 9 is aligned with the axis of the bell support 2 and thus the axis of the hollow shaft 8.

FIG. 1 is a partially sectional side view, FIG. 2 is a front view with one side omitted, and FIG. 3 is a rear view with one side omitted. The same parts as those of the conventional example (FIGS. 4 to 6) are designated by the same reference numerals, and the description thereof will be simplified or omitted.

In FIG. 1, a rotary atomizing type electrostatic coating machine 1 is shown.
Is a bell 3 rotatably mounted on the bell support 2 about its axis 9 and a plurality of (6) mounted on the electrode support 11 integral with the bell support 2 in a separated state on a virtual circle locus.
Book electrode (41), and the paint P2 atomized by using the rotation of the bell 3 is electrified using each grid electrode element (41, 44) while being applied to an object to be coated (not shown). It is configured to be electrostatically coated.

The paint is the water-based paint P2, and the charging means (4
1) is a grid electrode charging method. Further, the rotation mechanism (8, 8A, 8B) of the bell support 2, the bell 3, and the bell 3 and the paint supply pipe 6 are the same as those in the conventional example (FIGS. 4 to 6).

As shown in FIG. 1, the electrode support 11 has a hollow portion fitted and mounted on the bell support 2 and fixed integrally with the bell support 2 by bolts. A plurality of (six) mounting holes 15 are provided on the tip end surface side 13 of the electrode support 11 on a virtual circle locus having a diameter of DM1 and spaced at intervals of 60 degrees. Each mounting hole 15 is inclined outward. The inclination angle is selected and determined according to the length of the grid electrode element 41 and the size of the diameter DM2 of the virtual circular locus where the tip portion (discharge pin 44) is located.

A large diameter portion on the outside of each mounting hole 15 is provided with a screw that can be screwed into the perforated bolt member 34. This is because each grid electrode element 41 can be attached to and detached from each. The step portion 15 between the large diameter portion and the inner small diameter portion
A forms a locking portion. Each mounting hole 15 is an electrode support 1
It penetrates the groove 16 extended along the virtual circle locus in 1.

Further, one connection hole 14 is provided on the rear end surface side 12 of the electrode support 11 on a virtual circle locus. This connection hole 14 is similar to the case of each mounting hole 15,
It penetrates the groove 16. Further, the connection hole 14 is a tapered hole whose diameter decreases from the outside to the inside.

A ring-shaped conductor 21 is fitted in the groove 16 and filled with an insulating filler 17 after fitting. That is, the ring-shaped conductor 21 is embedded in the groove 16 in an electrically insulated state from the outside (2).

The ring-shaped conductor 21 has a role of applying the applied high voltage to each grid electrode element 41 (43T). The applicability to the increase and decrease of the number of grid electrode elements 41 is wide. It should be noted that the shape may not be an endless ring shape, but a shape in which a part in the circumferential direction is cut out. Considering fitting into the groove 5, a partially cutout shape is preferable.

The power supply cable 4 shown in FIGS. 1 and 3 is made of copper wire and has an outer peripheral surface covered with an electric insulating film.
A crossover lead wire 5 is attached to the tip of the copper wire. Therefore, the power supply cable 4 is connected to the connection hole 1 from the left side in FIG.
4 is inserted (fitted) into contact with the ring-shaped conductor 21 with a constant pressure. That is, a high voltage (for example, −8) is applied from the power supply cable 4 to the ring-shaped conductor 21.
0 KV) can be applied (powered).

By just inserting (fitting) the power supply cable 4 into the connection hole 14, the tip (copper wire) or the connection portion with the ring-shaped conductor 21 and the outside (bell support 2) are connected to each other.
The connection hole 14 and the power feeding cable 4 communicate with each other through a gap. That is, high voltage leakage occurs. Therefore, this gap is closed with an electric insulating material (31).

In this embodiment, the power supply cable 4
In order to make it detachable and convenient and easy for inspection and repair, the electric insulating material is formed of a stress cone 31 having high electric insulation and elasticity. The tip end of the stress cone 31 corresponds to the taper shape of the connection hole 14, and the base end part corresponds to the inner taper shape of the nut member 33. Further, the center hole of the nut member 33 is slightly smaller than the outer diameter of the power feeding cable 4 and can be fitted and mounted on the power feeding cable 4. The stress cone 31 may be integrally formed with the nut member 33 by, for example, bonding.

Thus, when the nut member 33 is screwed into the screw engraved on the outside of the connection hole 14 of the electrode support 11 and rotated, the stress cone 31 becomes a gap between the connection hole 14 and the power supply cable 4. Since it can be pressed into, the gap can be completely closed.

Therefore, the protection cylinder (7) which is high in rigidity and long in the case of the conventional example can be wiped out, and the high voltage leak to the outside (2) through the gap between the two can be completely prevented. The connection hole 14 can be brought closer to the bell support 2 side. That is, the diameter of the electrode support 11 can be reduced,
It is possible to achieve a significant reduction in size and weight. Power cable 4 is also 1
Since it is a book, the cable processing can be simplified and the space can be greatly saved from this point as well. In the case of this embodiment, D shown in the conventional example (FIG. 5) is formed to be selectable within 100 to 10 mm or less.

Each grid electrode element 41 constituting the charging means (grid electrode device) has an insulating cylinder 42, a current limiting resistor 43 mounted in the insulating cylinder 42, and a current limiting resistor 43.
And a discharge pin (tip portion) 44 having a tip protruding from the insulating cylindrical body 42 on the tip side. A terminal portion 43 for connecting the ring-shaped conductor 21 to the discharge pin 44 is provided on the base end side thereof.
T is connected via a current limiting resistor 43.

When the current limiting resistor 43 is externally attached, the discharge pin 44 and the terminal portion 43T may be connected by a lead wire, for example.

Further, the base end portion of the insulating cylinder 42 is formed as a taper portion 42B, and a flange-shaped engagement portion 42BF is provided on the large diameter portion side of the taper portion 42B. The engagement portion 42BF is locked to the step portion 15A in the mounting hole 15. Therefore, the position of each discharge pin 44 of each mounted grid electrode 41 can be accurately aligned on the virtual circle locus.

That is, if carbon fiber CF or a spring is inserted so that the terminal portion 43T can come into contact with it, and then the base end portion (42B) of the grid electrode element 41 is inserted (fitted) into the mounting hole 15. , The terminal portion 43T is made of carbon fiber C
It can be electrically connected to the ring-shaped conductor 21 (or the crossover lead wire 5) via F. However, in this state, a gap between the mounting hole 15 and the base end portion (42B) communicates with the outside (2), and a high voltage leak occurs. Therefore, the same electrical insulating material (stress cone 3) as the case of the connection hole 14 side is used.
Use 2) to close the gap.

The stress cone 32 has a tapered portion 4
2B has a taper hole that can be fitted and the outer shape is the mounting hole 1
5 can be inserted into the small diameter portion. The electrical insulation and elasticity are the same as those of the stress cone 31.

Thus, the grid electrode element 41 (42)
When the bolt member 34 fitted to the screw is screwed into the screw in the mounting hole 15 and rotated, the base end portion (42B) press-fits the stress cone 32. If the engaging portion 42BF comes into contact with the locking portion (step portion 15A) in the mounting hole 15 and is stopped, the gap between the mounting hole 15 and the base end portion (42B) is reliably closed with the electric insulating material (32). be able to.

In this mounted state, the tip end portion (44) of the grid electrode element 41 is located outside the base end portion (42B) about the axis 9 as shown in FIGS. That is, the outwardly inclined arrangement of each grid electrode element 41 can be established. At this time, the diameter DM2 of the virtual circle locus where the discharge pin 44 is located is equal to the diameter DMP of the atomization pattern PTN.
(Eg, 650 mm).

Therefore, the relative position of the tip portion (44) of each grid electrode element 41 and the bell 3 and each tip portion (44).
While the relative position between the atomization pattern PTN and the atomization pattern PTN can be easily set to an ideal state similar to the case of the conventional example (FIG. 4), the electrode support 11 can be significantly reduced in size and weight.

In the case of the embodiment having such a configuration, when the stress cone 31 and the nut member 33 are fitted on the power feeding cable 4, the tip thereof is inserted into one connection hole 14 and the nut member 33 is rotated, the power feeding cable 4 is rotated. The tip of the wire 4, that is, the crossover lead wire 5 is connected to the ring-shaped conductor 21 previously mounted in the groove 16. The stress cone 31 is press-fitted into the connection hole 14 by the rotation of the nut member 33, and completely closes the gap between the connection hole 14 and the power supply cable 4. That is, it is possible to reliably prevent the high voltage leak from the connection portion (5, 21) to the outside (11).

If the nut member 33 is rotated in the opposite direction,
The power supply cable 4 can be easily removed. Therefore, not only the assembly but also the inspection and repair can be greatly simplified.
Further, the gap between the power feeding cable 4 and the connection hole 14 is closed by the electric insulating material (31) and the ring-shaped conductor 21 is embedded in the electrode support 11 in an electrically insulated state by using the insulating filler 17. Since it is possible to eliminate the situation where the worker enters the high voltage range, the work safety is assured.

Next, the grid electrode element 41 to which the bolt member 34 is attached is inserted into the attachment hole 15. The carbon fiber CF is inserted in advance. When the bolt member 34 is rotated in this state, the taper-shaped base end portion (42) press-fits the stress cone 32 into the mounting hole 15, and therefore the terminal portion 43.
T can be connected to the ring-shaped conductor 21 via the carbon fiber CF, and the gap between the mounting hole 15 and the base end portion (42) can be completely closed. Complete prevention of high voltage leakage is established.

The rotation of the bolt member 34 depends on the engagement portion 42BF.
Stop in the state of being in contact with the stepped portion (locking portion) 15A in the mounting hole 15. The same applies to any of the grid electrode elements 41. Therefore, the tip end portion (discharge pin 44) of each grid electrode element 41 can be accurately positioned on the same virtual circle locus of the diameter DM2.

As described above, each grid electrode element can be individually attached / detached only by rotating the bolt member 34. Therefore, inspection and repair are simplified, and the grid electrode element 4 is
1 is easy to replace and the grid electrode element 4 has failed
Since only one needs to be replaced, the running cost can be reduced.

The supplied paint P2 forms an atomization pattern PTN by the rotation of the bell 3, and each grid electrode element 4
A high voltage (−80 KV) is applied to 1 from the power supply cable 4 via the ring-shaped conductor 21. The atomized paint (P2) can be electrostatically applied to the object to be coated while being negatively charged by the charge from each discharge pin 44.

At this time, since the relative positions of the discharge pins (tips) 44 and the atomization pattern PTN are maintained in an ideal state, the charging efficiency is very high. High-voltage leakage does not occur between the bell support 2 and the bell 3.

Further, since the electrode support 11 is downsized, the turbulent flow generated on the downstream side of the electrode support 11 is smaller than that of the conventional example. Therefore, the coating material P attached to the tip portions (44, 43) and the like.
2 is a very small amount. Therefore, since the interval of the cleaning work can be greatly extended, the production efficiency can be greatly improved and the cleaning work can be simplified. Easy to handle.

Further, since the electrode support 11 that affects the robot arm side is significantly reduced in size and weight, the load on the robot side is reduced, the cost is reduced, the cable processing is facilitated, and the moving range of the bell 3 is reduced. The automation of coating including expansion and speeding up of moving speed can be dramatically promoted. Further, since the coating machines 1 can be arranged in rows at small intervals, it is also effective for downsizing the coating booth and the like.

According to this embodiment, however, each grid electrode element 41 is provided on the tip surface side 13 of the electrode support 11 and each base hole (42B) is utilized by utilizing each mounting hole 15 inclined outward. Is inclined outward so that the tip (44) of the bell 3 is on the outside centering on the rotation axis (9) of the bell 3,
The electrode support body 11 includes the power supply cable 4 fitted in one connection hole 14 provided on the rear end surface side 12 of the electrode support body 11 and the terminal portion 43T of each grid electrode element 41 fitted in each mounting hole 15. 11 are connected to each other via a ring-shaped conductor 21 embedded in 11 so as to be able to supply power, and a gap between the fitted power feeding cable 4 and the connection hole 14 and a base end portion of each fitted grid electrode element 41. Since the gaps between 42B and the mounting holes 15 are closed by the electric insulating materials 31 and 32, high voltage leakage to the outside (2) through the gaps can be prevented, so that the desired charging efficiency, It is compact and lightweight while ensuring coating quality and work safety, and simplifies cleaning work and facilitates automated coating.

Further, the electric insulating material is the stress cone 31,
Since it is composed of 32, the gaps can be more surely closed, and the feeding cable 4 and the grid electrode elements 41 can be easily attached and detached.

Further, since the stress cone 31 and the connection hole 14 are formed in a tapered shape so that the stress cone 31 can be press-fitted, the gap can be completely closed. The same applies to the relationship between the stress cone 32 and each mounting hole 15.

Further, since only one power supply cable 4 is required, the cable treatment is facilitated, and the protection tube (7) can be swept away, so that space saving and cost reduction can be further promoted.

Further, since each mounting hole 15 has an outwardly inclined shape, each grid electrode element 41 can be easily arranged in an outwardly inclined manner, and the step portion 15A and the engaging portion 42BF are provided. Therefore, the tip (44) can be positioned quickly and accurately.

Further, since each grid electrode element 41 is detachable by rotating the bolt member 34, the grid electrode elements can be individually and easily replaced.

Further, since each grid electrode element 41 is formed so as to be applied with a high voltage via the ring-shaped conductor 21, the applicability to increase or decrease in the number of grid electrode elements 41 is wide.

In the above embodiment, in order to achieve the purpose of making the power supply cable 4 and each grid electrode element 41 attachable to and detachable from the electrode support 11, the electrical insulating material that closes each gap is provided from the stress cones 31 and 32. Although formed, this electric insulating material may be formed of, for example, an adhesive electric insulating agent. Further, when the grid electrode element 41, the electrode support 11 and the power supply cable 4 may be handled as a unit, the power supply cable 4, the ring-shaped conductor 21, the ring-shaped conductor 21 and each grid electrode element 41 (43T). The respective joints with and may be entirely molded with, for example, an electrically insulating resin.

[0062]

According to the present invention, each grid electrode element is provided on the tip end surface side of the electrode support, and each of the mounting holes inclined outward is utilized to make the rotation axis of which the tip end is bell rather than the base end. , Which are arranged so as to be outwardly inclined with respect to the center, are fitted into one connecting hole provided on the rear end face side of the electrode support body, and each grid electrode fitted into each mounting hole. The terminal portion of the element is connected to each of them via a ring-shaped conductor embedded in the electrode support body so that power can be supplied to each, and the gap between the fitted power feeding cable and the connection hole and the fitted grid electrode element Since each of the gaps between the base end portion and each mounting hole is closed with an electric insulating material so as to prevent high voltage leakage to the outside through each gap, the following excellent effects are achieved.

Since the diameter of the electrode support can be reduced by completely preventing high voltage leakage, it is possible to achieve significant space saving and size reduction and weight reduction. Therefore, the turbulent flow on the downstream side of the electrode support becomes slight, and the paint adhesion to each grid electrode element etc. can be greatly reduced, so that the cleaning work can be simplified.
Productivity can be improved while ensuring coating quality. The reduction in size and weight of the electrode support facilitates automation of coating, and contributes greatly to expanding the range of movement of the bell, increasing the speed of movement, and reducing the capacity and cost of the robot itself. Further, the arrangement pitch of the coating machines can be reduced.

Since only one high-voltage power supply cable is required, it is possible to simplify the cable processing and facilitate the automation of coating. Further, since the conventional protection cylinder can be wiped out, the cost can be reduced and the work safety can be greatly improved.

Since the relative position between each tip and the atomization pattern can be set to an ideal state by the outwardly inclined arrangement of each grid electrode element, the charging efficiency of the paint can be further improved. Further, since the relative position between each tip and the grid electrode element can be maintained, it is possible to completely prevent high voltage leak to the electrode support side. Since the structure is such that a high voltage is applied to the plurality of grid electrode elements via the ring-shaped conductor in the electrode support, the applicability to the number of grid electrode elements is wide.

[Brief description of drawings]

FIG. 1 is a partially sectional side view showing an embodiment of the present invention.

FIG. 2 is likewise a front view with one side omitted.

FIG. 3 is likewise a rear view with one side omitted.

FIG. 4 is a side view for explaining a conventional example.

FIG. 5 is a diagram for explaining a mounting state of a power supply cable and a grid electrode element, similarly.

FIG. 6 is also a diagram for explaining the bell rotation mechanism.

[Explanation of symbols]

 1 Rotary atomizing electrostatic coating machine 2 Bell support 3 Bell 4 Feed cable 5 Crossover lead wire 7 Holding tube 11 Electrode support 12 Rear end face side 13 Tip end face side 14 Connection hole 15 Mounting hole 15A Step 16 Groove 17 Insulation Filler 21 Ring-shaped conductor 31 Stress cone (electrical insulating material) 32 Stress cone (electrical insulating material) 33 Nut member 34 Bolt member 41 Grid electrode element 42 Insulating cylinder 42B Tapered part (base end) 42BF Engaging part 43 Current limiting resistance 43T Terminal part 44 Discharge pin (tip part)

Claims (1)

[Claims] 1. A bell rotatably mounted on a bell support, and a plurality of grid electrode elements mounted on the electrode support integral with the bell support in a separated state on a virtual circle locus, In a rotary atomization type electrostatic coating machine for electrostatically painting an object to be coated while charging atomized paint using the rotation of a bell by using each grid electrode element, wherein each grid electrode element is supported by the electrode. Utilizing the mounting holes that are provided on the distal end surface side of the body and are inclined outward, the outwardly inclined arrangement is made so that the distal end portion is outside the base end portion with the rotation axis of the bell as the center. A ring shape in which a power supply cable fitted into one connection hole provided on the rear end face side of the electrode support and a terminal portion of each grid electrode element fitted into each mounting hole are embedded in the electrode support. Connected so that power can be supplied to each via a conductor, Prevents high voltage leakage to the outside through each gap by closing the gap between the power supply cable and the connection hole and the gap between the fitted base end of each grid electrode element and each mounting hole. A rotary atomizing type electrostatic coating machine characterized by being formed as much as possible.