JPH06296905A - Electrostatic powder coating device - Google Patents

Abstract

PURPOSE:To realize the simplification of equipment by installing a porous support body for mounting a powder coating material on it, forming a pressurized air chamber sectioned by a porous electrode plate below it and electrifying the pressurized air before feeding the powder coating material to a coating material chamber to float it, causing a work to be coated with it. CONSTITUTION:In a case 1 where a flange 2 is formed at an open end in the upper part, a pressurized air chamber 3, an air filling chamber 4 and a coating material housing chamber 5 are formed in this order from below. The chambers 3, 4 are partitioned by a porous electrode plate 6 and the chambers 4, 5 are partitioned by a porous support plate 7. Pressurized air 9 is fed to the pressurized air chamber 3 from an air feed source 8 and electrified while passing through the porous electrode plate 6 and the pressurized air 9 after electrification is fed to the coating material chamber 5 through the porous support plate 7, causing the powder coating material the float and also to be negatively charged. And the powder coating material 11 is made to stick to a work 13 which is grounded through a carrying screw 14 and is being carried, and is fixed by heating.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is to charge powder powder paint by bringing charged dry air into contact with the powder paint, and then electrostatically apply the paint to the work (work) and heat fixing. The present invention relates to an electrostatic powder coating device.

[0002]

2. Description of the Related Art Conventionally, various electrostatic powder coating devices of this type have been devised and put into practical use. As one form, there is known a device that uses a brush-shaped electrode and supplies the air flow intensively to the tip of the brush where the lines of electric force are concentrated to efficiently charge the air.

[0003]

However, in the conventional electrostatic powder coating apparatus using the brush-shaped electrode, it is difficult to position the air ejection port in order to concentrate the air flow on the tip of the brush. However, there is a problem that a nozzle for concentrating the air flow at the tip of the brush needs to be used, resulting in a complicated structure. Moreover, in the conventional device,
There is a problem in that it is not possible to uniformly charge all of the air supplied to the electrode side, resulting in uneven charging.

The present invention has been made to solve the above problems, and provides an electrostatic powder coating apparatus capable of simplifying the structure and uniformly charging an air flow. The purpose is to

[0005]

SUMMARY OF THE INVENTION An electrostatic powder coating apparatus according to the present invention is provided with a porous support plate which is arranged on the downstream side of an air flow and on which a powder coating material is placed, and the porous support plate. A porous electrode plate which is arranged apart from the porous support plate on the upstream side of the air flow to form a pressurized air chamber, and a high voltage generating means for applying a high voltage to the porous electrode plate, An air supply unit for supplying air to the pressurized air chamber, wherein the porous electrode plate serves as the only discharge path for the air discharged from the pressurized air chamber to the porous support plate side. It is characterized by being

[0006]

According to the present invention, a part of the pressurized air chamber for introducing the air flow supplied from the air supply means is formed by the porous electrode plate, and this porous electrode plate is the only discharge path for air. Therefore, the air flow passing through the uniformly charged porous electrode plate is uniformly charged and supplied to the powder coating material. Further, according to the present invention, it is not necessary to accurately position the jetting position of the air flow, and since a complicated electrode structure is not provided, the device configuration becomes extremely simple.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view showing the configuration of the essential parts of an electrostatic powder coating apparatus according to an embodiment of the present invention. Inside the case 1 with the flange 2 formed at the open end of the upper part,
Pressurized air chamber 3, charging chamber 4 and paint storage chamber 5 in this order from the bottom.
Are formed respectively. The pressurized air chamber 3 and the charging chamber 4 are partitioned by a porous electrode plate 6, and the charging chamber 4 and the paint accommodating chamber 5 are partitioned by a porous support plate 7.

Air (dry air) 9 is supplied to the pressurized air chamber 3 from an air supply source 8. The air 9 supplied to the pressurized air chamber 3 passes through the porous electrode plate 6 as the only air outlet, and moves to the charging chamber 4. A high voltage of about 75 kV from the high voltage generator 10 is applied to the porous electrode plate 6. As the porous electrode plate 6, for example, a sintered body of metal particles made of bronze, stainless steel or the like and having a diameter of several hundred microns is suitable. Moreover, an insulator such as a resin material may be used as the porous support plate 7.

A powder coating material 11 is stored in the coating material storage chamber 5. The powder coating material 11 is made of vinyl chloride resin, epoxy resin, polyethylene resin or the like. The level of the powder coating material 11 is detected by a level sensor 12, and a necessary amount of the powder coating material 11 is supplied from a coating material supply means (not shown) as needed. Above the paint storage chamber 5, a work 13 to be painted is, for example, a transport screw 14
It is supposed to be transported by.

According to the electrostatic powder coating apparatus having the above structure, when a high voltage is applied to the porous electrode plate 6, the surface of the porous electrode plate 6 is uniformly charged. On the other hand, the air 9 supplied from the air supply source 8 once stays in the pressurized air chamber 3 and uniformly passes through the porous electrode plate 6 due to the pressure difference between the inside and outside to reach the charging chamber 4. At that time, the air 9 passing through the electrode plate 6 is uniformly charged by the charges on the surface of the electrode plate 6.

The charged air 9 passes through the porous support plate 7 and uniformly charges the powder coating material 11 to a negative charge. On the other hand, since the work 13 is grounded, for example, via the conveying screw 14, the powder paint 11 adheres to the work 13 due to the Coulomb force generated between the work 13 and the powder paint 11.
After that, after the excess paint on the work 13 is removed by a means (not shown), the paint is fixed by heating. Excess paint is collected by paint collecting means (not shown).

As described above, according to this electrostatic powder coating apparatus, there is an advantage that the air to be supplied can be uniformly charged and the structure is simplified. The porous support plate 7
The distance between the porous electrode plate 6 and the porous electrode plate 6 may be set to a desired value in consideration of the voltage value applied to the electrode plate 6 and the charging efficiency and safety. Further, the plurality of porous electrode plates 6 may be provided, or the porous electrode plates 6 may be provided not on the lower side of the porous support plate 7 but on the lateral side thereof. In short, it is sufficient to dispose the porous electrode plate on the upstream side of the air flow with respect to the porous support plate.

[0013]

As described above, according to the present invention, a part of the pressurized air chamber for introducing the air flow supplied from the air supply means is formed by the porous electrode plate, and this porous electrode is used. Since the plate is the only discharge path for air, the air flow passing through the uniformly charged porous electrode plate can be uniformly charged, and the device can be simplified. Play.

[Brief description of drawings]

FIG. 1 is a sectional view of an electrostatic powder coating apparatus according to an embodiment of the present invention.

[Explanation of symbols]

1 ... Case, 2 ... Flange, 3 ... Pressurized air chamber, 4 ... Filling chamber, 5 ... Paint storage chamber, 6 ... Porous electrode plate, 7 ... Porous support plate, 8 ... Air supply source, 9 ... Air , 11 ... Powder coating, 1
2 ... Level sensor, 13 ... Work, 14 ... Conveying screw.

Claims (1)

[Claims] 1. A porous support plate which is arranged on the downstream side of the air flow and on which the powder coating material is placed, and the porous support plate is separated from the porous support plate on the upstream side of the air flow. A porous electrode plate that is disposed in a compressed air chamber to form a pressurized air chamber, a high voltage generator that applies a high voltage to the porous electrode plate, and an air supply unit that supplies air to the pressurized air chamber. The electrostatic powder coating apparatus is characterized in that the porous electrode plate serves as the only discharge path for the air discharged from the pressurized air chamber to the porous support plate side.