JPH067708A - Grid electrode apparatus of rotary atomizing-type electrostatic coating apparatus - Google Patents

Abstract

PURPOSE:To easily carry out replacement work which follows break of a grid electrode and improve the economization. CONSTITUTION:A grid electrode 11 is composed of a current-limiting resistor 22, an electrode pin 25 installed at the tip part of the current-limiting resistor 22, and an insulating cylindrical body 31 wherein the current-limiting resistor is connected with a high voltage electric cable 12 through a connecting part 13 in the way it can change the position and the insulating cylindrical body 31 is attached to an installation main body in freely detachable way and covers at least the connecting part and the current-limiting resistor 22 to insulate their outside in the way that the insulating cylindrical body can move relatively. The insulating cylindrical body is so formed as to make the tip part 32 covering the current-limiting resistor 22 small in diameter and the rear part 33 of the insulating cylindrical body 31 larger in diameter than the tip part 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grid electrode device for a rotary atomizing electrostatic coating machine.

[0002]

2. Description of the Related Art FIG. 3 shows an example of a conventional rotary atomizing electrostatic coating machine.

Conventionally, as a rotary atomizing type electrostatic coating machine, a paint (for example, a water-based paint) P atomized by a bell 3 rotating in a predetermined direction is negatively charged by using a grid electrode device 1A, and a positive electrode side (ground side). ) Is known to be attached to an object to be coated (not shown) and is used for coating automobile bodies and the like.

The electrostatic coating machine comprises a bell support 2 for supporting the bell 3 so as to be rotatable about an axis 9 and a grid electrode device 1A attached to the bell support 2. It is common to have

Here, the grid electrode device 1A has a bell support 2 via an electrically insulating and disk-shaped mounting body 19.
(And the bell 3) are arranged so as to include a predetermined number (for example, 6) of grid electrodes 41 arranged so as to surround them.

Each grid electrode 41 is, as shown in FIG.
The current limiting resistor 43 is formed in an elongated rod shape and is connected to the high voltage electric wire 42, the electrode pin 44 attached to the tip of the current limiting resistance 43, the high voltage electric wire 42 and the current limiting resistor 43.
It is configured to include an insulating cylindrical body 45 that covers the above and externally insulates.

The electrode pin 44 has a current limiting resistor 43.
High voltage (eg -65kV) from the high voltage line 42 via
Short circuit current is supplied. Also, normally, the insulating cylinder 45
Is formed of a synthetic resin (for example, Teflon) having electric insulation. The insulating cylinder 45 is insulation-bonded to the mounting body 19. The electrode pin 44 projects from the tip of the insulating cylinder 45 by a predetermined length. In this way, the grid electrode 41 includes the components (42, 43, 44, 4).
5) are integrally provided.

[0008]

By the way, since each grid electrode 41 of the above-mentioned grid electrode device 1A is elongated and protrudes from the mounting body 19, the assembly, inspection,
It may be broken by being hit by a tool or the like during cleaning, or by interfering with an object to be coated (work) during setting (as a breaking point, a connecting portion with the mounting body 19 where the maximum bending moment tends to act). There are many.).

Here, since the grid electrode 41 is integrally provided with each component, it is not necessary to replace only the broken component, and the entire grid electrode 41 must be replaced. Often not. In such a case, the broken grid electrode 41 is attached to the mounting body 1
After removing from 9, the alternative grid electrode (41) must be insulated and bonded to the mounting body 19 and connected to an external power source, which is a troublesome task. There is also a problem from the economical point of view.

In view of the above circumstances, an object of the present invention is to make a grid of a rotary atomization type electrostatic coating machine capable of simplifying the replacement work due to breakage of the grid electrode and improving the economical efficiency. An object is to provide an electrode device.

[0011]

A grid electrode device of a rotary atomizing electrostatic coating machine according to the present invention is arranged in a mounting body so as to surround a bell which rotates in a predetermined direction to atomize a paint. In a grid electrode device of a rotary atomization type electrostatic coating machine having a predetermined number of rod-shaped grid electrodes, the grid electrode is connected to a high-voltage electric wire via a connecting portion so that the attitude can be changed and a current limiting resistance and a current limiting An insulating tubular body, which includes an electrode pin provided at the tip of the resistor, an insulating tubular body detachably attached to the mounting body, and at least a connecting member and an insulating tubular body that externally insulates the current limiting resistor so as to be relatively movable. Is characterized in that the diameter of the front portion that covers the current limiting resistance is small and that the diameter of the rear portion of the insulating cylinder is larger than that of the front portion.

[0012]

According to the present invention having the above-mentioned structure, for example, when a cleaning tool or the like hits the tip portion of the insulating tubular body of the grid electrode during cleaning and an excessive bending force acts on the electrode, the rear portion of the insulating tubular body is applied. Has a larger bending moment than the tip. However, since the rear part of the insulating cylinder has a larger diameter and a larger bending strength than the tip part, it does not break, and the tip part breaks (the bending moment is the maximum at the breaking point). There are many connection parts with the rear part.)

At this time, the mounting posture of the current limiting resistance with respect to the high voltage electric wire is changed as the tip portion of the insulating cylinder is broken. However, since the current limiting resistance is connected to the high-voltage electric wire via the connecting portion so that the posture can be changed, no bending stress is generated and the current limiting resistance is not broken.

Therefore, it is often necessary to replace only the insulating cylinder, and the replacement work due to breakage of the grid electrode is simplified. Moreover, since the components can be reused, the economical efficiency is improved.

[0015]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a main part of a grid electrode device according to the first embodiment.

(First Embodiment) A grid electrode device 11 of a rotary atomizing electrostatic coating machine according to the first embodiment includes a disc-shaped mounting body 19 mounted on a bell support (not shown). It is configured to include a predetermined number of rod-shaped grid electrodes 11 arranged on the mounting body 19.

In the present embodiment, the mounting body 19 is made of Teflon which is excellent in electrical insulation. The number of grid electrodes 11 installed is six.

Each grid electrode 11 is a high voltage electric wire 1.
2 and a current limiting resistor 22 connected to the position changeable via a connecting portion 13, an electrode pin 25 provided at the tip of the current limiting resistor 22, and at least a connecting portion detachably attached to the mounting body 19. 13 and the current limiting resistor 22 are movably covered to insulate the outside by an insulating cylinder (31).

Here, the high-voltage electric wire 12 can supply a high-voltage (-65 kV in this embodiment) short-circuit current from an external power supply device (not shown) to the electrode pin 25 via the connection portion 13 and the current limiting resistor 22. Is formed in.

Further, in this embodiment, the connecting portion 13
Is configured to include the connection fitting 14 and the spring 26. The connection fitting 14 is attached to the tip of the high-voltage electric wire 12, and the surface that comes into contact with the rear end surface of the current limiting resistor 22 is formed in an arcuate cross section. Then, due to the elastic force of the spring 26, the current limiting resistance 22 is pressed against the connection fitting 14.
As a result, the high-voltage electric wire 12 and the current limiting resistor 22 are connected to each other via the connecting fittings 14 so that their postures can be changed and they can be separated from each other.

The current limiting resistor 22 is means for preventing a rapid change in the current value and limiting the short circuit current value flowing through the electrode pin 25 to a predetermined value (500 μA in this embodiment) or less.

Further, in the insulating cylinder (31), the front portion (32) covering the current limiting resistance 22 has a small diameter, and the rear portion (33) has a larger diameter than the front portion (32). . In this embodiment, the insulating cylinder is formed of the register cap 31. Register cap 31
Is configured to cover the connection portion 13, the current limiting resistance 22, most of the high electric wire 12 and the base end portion of the electrode pin 25 for external insulation. Here, the tip portion 32 of the register cap 31 covers the current limiting resistance 22 and the base end portions of the electrode pins 25, and has a small diameter (diameter D1 = 15 mm). The proximal ends of the current limiting resistor 22 and the electrode pin 25 are accommodated in the front portion 32 of the register cap 31 so as to be relatively movable, and the current limiting resistor 22 and the electrode pin 25 are accommodated.
A spring 26 is contracted between and. This spring 26
Is made of stainless steel. The tip of the electrode pin 25 projects outward from the tip portion 32 of the register cap 31 by a predetermined length.

The rear portion 33 of the register cap 31 covers the high-voltage electric wire 12 and the connecting portion 13, and has a larger diameter (diameter D2 = 35 mm) than the front portion 32. In particular, in this embodiment, in order to increase the structural strength and the like, the rear portion 3 of the register cap 31 is used.
3 is detachably attached to the attachment body 19 via a sleeve 18 as a reinforcing member. Where the sleeve 1
A male screw portion 18a is formed on the outer peripheral surface 18b on the rear side of 8, and the male screw portion 18a is screwed into a mounting screw hole portion 19a formed in the mounting body 19. Also, sleeve 1
The above-mentioned high-voltage electric wire 12 is housed inside 8 so as not to contact the inner peripheral surface via the filling material 29. The rear portion 33 of the register cap 31 is formed such that the inner peripheral surface 33b thereof is in close contact with the outer peripheral surface 18b of the sleeve 18, and the inner peripheral surface 33 near the mounting body 19 thereof.
A female screw portion 33a that is screwed with the male screw portion 18a of the sleeve 18 is formed in the portion b. A packing 28 is interposed between the rear portion 33 of the register cap 31 and the mounting body 19.

As described above, the rear portion 33 of the register cap 31 is reinforced by the sleeve 18, and the bending strength is further increased as compared with the front portion 32 in consideration of the fact that the rear portion 33 has a large diameter.

In FIG. 1, 19b is an annular mounting ring made of an electrically insulating material (Teflon in this embodiment), which is mounted on the rear end surface of the mounting body 19. The mounting ring 19b electrically insulates the high-voltage electric wire 12 and the like housed in the mounting body 19 from the outside.

Next, the operation will be described. When a tool or the like hits the tip portion 32 of the register cap 31 of the grid electrode 11 and an excessive bending force acts on the cap 31 during inspection, the rear portion 33 of the register cap 31 is larger than the tip portion 32. Bending moment acts. However, since the rear portion 33 has a larger diameter and a larger bending strength than the front portion 32, the rear portion 33 is not broken, and the front portion 32 is broken (the rear portion where the bending moment is maximum is the broken portion). There are many connection parts with 33).

At this time, the mounting posture of the current limiting resistor 22 with respect to the high voltage electric wire 12 is changed as the tip portion 32 of the resistor cap 31 is broken. However, the current limiting resistor 22
Since it is connected to the high-voltage electric wire 12 via the connecting portion 13 so that the posture can be changed, no bending stress is generated and it is not broken.

Therefore, it is often necessary to replace only the register cap 31, and the replacement work is simplified. Further, since the component parts such as the current limiting resistor 22 can be reused, the economical efficiency is improved.

(Second Embodiment) As shown in FIG. 2, the grid electrode device according to the second embodiment is different from the grid electrode device according to the first embodiment in that the front portion (35) and the rear portion of the insulating cylinder are formed. (37) is separably formed, and the structure of the connecting portion 13A is different from that of the first embodiment. The other components except for the insulating cylinder and the connecting portion 13A have the same configuration as the corresponding components of the grid electrode device according to the first embodiment, and thus detailed description thereof will be omitted.

Here, the insulating cylinder has a register housing 35 at its front portion and a retainer cap 37 at its rear portion. The register housing 35 is configured to cover a part of the connecting portion 13 (spring 17 or the like), the current limiting resistor 22 and the base end portion of the electrode pin 25. The spring 17, the current limiting resistor 22 and the electrode pin 25 are provided in the register housing 35 so as to be movable in the axial direction. At the rear portion of the register housing 35, the protrusion 3 that abuts on the tip surface 18c of the sleeve 18 is provided.
6 is formed. An outer peripheral surface 35a portion of the register housing 35 rearward of the protruding portion 36 is formed so as to be in close contact with the inner peripheral surface 18d of the sleeve 18.

On the other hand, the retainer cap 37 is formed so that its inner peripheral surface 37b is in close contact with the outer peripheral surface 18b of the sleeve 18, and the inner peripheral surface 37b of the retainer cap 37 near the mounting body 19.
A female screw portion 37c which is screwed with the male screw portion 18a of the sleeve 18 is formed in the portion. The retainer cap 37 is connected to the register housing 3 via the sleeve 18.
5 is formed so that it can be fitted therein, and is formed to have a diameter (diameter D2 = 32 mm) larger than the register housing 35 (diameter D1 = 16 mm in this embodiment). An opening is formed in the tip portion 37 a of the retainer cap 37, and the opening is formed in the outer peripheral surface 35 of the register housing 35.
It is formed so as to be in close contact with a.

When the retainer cap 37 is appropriately rotated and tightened, the tip portion 37a of the retainer cap 37 presses the protrusion 36 of the register housing 35 and fixes it to the sleeve 18 (and hence the mounting body 19).

The connecting portion 13A includes a crimp terminal 15, a screw 16a, a nut 16b and a spring 17. The crimp terminal 15 includes a sleeve 18 and a nut 16b.
The high-voltage electric wire 12 is connected to the screw 16a fixed via the. Further, the spring 17 includes a nut 16b (screw 16
It is contracted between a) and the current limiting resistor 22. Therefore, the high-voltage electric wire 12 and the current limiting resistor 22 can be changed in posture and can be separated from each other by the crimp terminal 15, the screw 16a, and the nut 16b.
And a spring 17 for connection.

From the above, for example, when an excessive bending force is applied to the register housing 35 of the grid electrode 11, the retainer cap 37 has a large diameter and a bending strength larger than that of the register housing 35, and therefore the housing is not broken. 35 will be broken. At this time, since the register housing 35 can be separated from the retainer cap 37, it is often necessary to replace only the register housing 35, and the replacement work is further simplified. Further, the economical efficiency can be further improved by minimizing the replacement parts.

In the first and second embodiments, the electrode pin 25 and the current limiting resistor 22 are connected by the elastic force of the spring 26 and are separable, so that only one of them is connected. If damaged, both (25,
22) It does not need to be replaced, and the economy can be further improved.

[0036]

According to the present invention, since the diameter of the front portion of the insulating cylinder covering the current limiting resistance is small and the diameter of the rear portion of the insulating cylinder is larger than that of the front portion, the grid electrode When an excessive bending force is applied to the insulating cylindrical body, the tip portion, which is weak in strength, is broken. At this time, the current limiting resistance coated on the tip portion is changed in posture with respect to the high voltage electric wire, but since the connection portion allows such posture change, bending stress does not occur and it is not broken. Therefore, it is often necessary to replace only the insulating cylindrical body, and the replacement work associated with breakage of the grid electrode can be simplified and the economical efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of a first embodiment of the present invention.

FIG. 2 is a sectional view showing a main part of a second embodiment of the present invention.

FIG. 3 is a diagram for explaining a schematic configuration of a conventional rotary atomizing electrostatic coating machine.

FIG. 4 is a view for explaining a grid electrode device of a conventional rotary atomizing electrostatic coating machine.

[Explanation of symbols]

 11 grid electrode 12 high-voltage electric wire 13, 13A connection part 19 mounting body 22 current limiting resistance 25 electrode pin 31 register cap (insulating cylinder)

Claims (1)

[Claims] 1. A grid electrode device of a rotary atomization type electrostatic coating machine having a predetermined number of rod-shaped grid electrodes arranged in a mounting body so as to surround a bell that rotates in a predetermined direction and atomizes a paint. , The grid electrode is connected to the high-voltage electric wire via a connecting portion so that the attitude can be changed, an electrode pin provided at the tip of the current limiting resistance, and detachably attached to the mounting body and at least connected. A member and an insulating cylinder that covers the current limiting resistance so as to be movable relative to each other and externally insulates, and a tip portion of the insulating cylinder that covers the current limiting resistance has a small diameter, and a rear portion of the insulating cylinder is A grid electrode device for a rotary atomization type electrostatic coating machine, which has a larger diameter than the tip portion.