JP2727472B2 - Electrostatic painting of automobile bodies - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electrostatic coating method for an automobile body.

(Prior Art) In the manufacture of automobiles, the outer surface of the vehicle body is painted in order to prevent rust of the vehicle body steel plate and enhance the overall aesthetics of the vehicle to ensure its commercial value. Usually, an electrodeposition coating is applied to a vehicle body steel plate, and a primer coating, an intermediate coating, and a top coating are sequentially applied on the coating surface.

Among the above-mentioned electrodeposition coatings, the electrostatic coating is a method in which a vehicle body is charged with static electricity, and is passed through a paint powder zone in which the opposite static electricity is charged, thereby causing the paint powder to electrostatically adhere to the vehicle body. After that, the whole is heated to bake the paint on the car body.

This electrostatic coating method is economical in that the amount of paint wasted during coating is small.

(Problems to be Solved by the Invention) However, the above-described electrostatic coating method has the following problems.

For example, the door portion of the automobile shown in the perspective view of FIG. 4 is a cross-sectional view taken along the line VV. As shown in FIG. It has a structure in which a hole 3 for mounting a cylinder is formed.

When the body steel plate 1 having such a hole is subjected to electrostatic coating, the peripheral edge portion 2a of the hole 2 and the peripheral edge portion 3a of the hole 3 are more static than the other flat portions of the vehicle body steel plate 1. The electrical effect is intensively expressed. As a result, these ends
A large amount of paint is applied compared to other flat parts.

Therefore, when the paint is dried or baked, the paint applied in a large amount hangs down in the vertical direction, and holes 2 and 3
In this case, paint dripping portions 4a, 4b, and 4c are generated, which become obstacles when attaching the respective members to the holes 2 and 3.

In order to prevent such dripping of paint,
What is necessary is just to make the thickness of the coating film formed in that part thin. However, such a treatment is effective in reducing the amount of dripping of the paint at the peripheral edge of the holes 2 and 3, but the coating thickness of the flat part of the body steel plate 1 other than the holes 2 and 3 is effective. Becomes thinner, and the overall finish is not in an appropriate state.

The present invention solves the above-mentioned problem when applying an electrostatic coating to a body steel plate having various holes formed therein, and does not cause the paint to hang down, and can be compared with the peripheral edge of the hole and other flat portions. It is an object of the present invention to provide an electrostatic coating method for an automobile body capable of forming a thick coating film.

(Problems to be Solved by the Invention) In order to achieve the above object, according to the present invention, when a vehicle body of an automobile is subjected to electrostatic coating, at a location where a predetermined hole is formed in a body steel plate, After performing a desired electrostatic coating by pressing a plate-shaped member having a metal film attached from the inside of the vehicle body so that the metal film is exposed to the outside of the vehicle body, removing the plate-shaped member from the location. A feature is provided for a method for electrostatic painting of an automotive body.

(Operation) In the present invention, since the electrostatic coating is performed in a state where the hole of the vehicle body steel plate is closed from the inside by the plate member, the electrostatic effect concentrated on the peripheral edge of the hole is reduced by the plate member. Is reduced compared to the case where no is used.

Therefore, even if a relatively thick coating film is formed on the flat portion of the vehicle body steel plate, a large amount of paint is not concentrated and applied to the peripheral edge of the hole, and the amount of dripping of the paint is reduced.

(Example) Hereinafter, a method of an example of the present invention will be described with reference to the accompanying drawings. First, as shown in FIG. 1, a plate-like member 13 is closed from the inside of a vehicle body steel plate 11 in which a hole 12 such as a key cylinder mounting hole and a door indol mounting hole is formed. Is pressed.

The plate-shaped member 13 is composed of a base material 13a and a metal foil 13b having a high electrostatic effect such as an aluminum foil attached to the surface of the base material 13a. It is preferable that the base material 13a is made of a material such as a rubber magnet that is appropriately flexible and can be adsorbed to the vehicle body steel plate 11 by itself. Body steel plate of plate-shaped member 13
This is because it is easy to attach and detach to 11.

The plate-shaped member 13 is pressed from the inside of the hole 12 with the metal foil 13b facing the painted surface side, so that the peripheral edge 11a of the hole 12 is formed.
, The concentration of the electrostatic effect in this portion is reduced.

Next, electrostatic painting is performed while maintaining this state. Hole 12
Since the electrostatic effect does not concentrate on the peripheral edge 11a of the steel plate, the other flat portion 11b of the body steel plate 11, the peripheral edge 11a of the hole, and the surface of the metal foil 13a exposed on the painted surface side are also substantially The paint is applied with a uniform thickness.

Then, the whole is dried. At this time, the peripheral edge 11 of the hole
Since no excess paint is attached to a, the portion does not hang down and a coating film 14 having a substantially uniform thickness is formed (FIG. 2).

Thereafter, the plate member 13 is removed from the vehicle body steel plate 11. The coating portion 14a formed on the surface of the metal foil 13b
It is removed as it is attached to b, and the hole in the vehicle body steel plate 11 reappears.

At this time, the coating portion on which the peripheral edge portion 11a of the hole was formed does not hang down, and the peripheral edge portion 11a is left as it is.
It remains in a (FIG. 3).

With respect to the removed plate-like member 13, the metal foil 13b on the surface can be replaced with a new metal foil, and the same can be used again for electrostatic coating.

(Effects of the Invention) As is apparent from the above description, the electrostatic coating method for an automobile body according to the present invention provides a method for applying an electrostatic coating to an automobile body when a predetermined hole is formed in a body steel plate. Then, after applying a desired electrostatic coating by pressing a plate-like member having a metal film attached to the location from the inside of the vehicle body so that the metal film is exposed to the outside of the vehicle body, the plate-like member is attached to the location. As described above, since a large amount of paint is prevented from being applied based on the concentration of the electrostatic effect at the peripheral edge of the hole, the problem of dripping of the paint in that portion is eliminated. .

Therefore, a thick coating film can be formed as a whole, and the overall coating finish can be improved.

[Brief description of the drawings]

1 to 3 are schematic views showing the steps of a method according to an embodiment of the present invention, FIG. 4 is a perspective view of an automobile, and FIG. 5 is a partial sectional view taken along line VV in FIG. is there. 11 ... body steel plate, 11a ... peripheral edge of hole, 12 ... hole, 13
... plate-like member, 13a ... base material, 13b ... metal foil, 14 ... coating film, 14a ... coating film portion.

Claims (1)

(57) [Claims] When a vehicle body of an automobile is subjected to electrostatic coating, at a place where a predetermined hole is formed in a body steel plate, a plate-like member having a metal film attached to the place from the inside of the vehicle body is attached to the metal film. And performing a desired electrostatic coating by press-contacting such that it is exposed to the outside of the vehicle body, and then removing the plate-shaped member from the location.