JPS58157994A - Electrodeposition painting device - Google Patents

Abstract

PURPOSE:To paint the entire part of vehicle bodies thoroughly by electrodeposition in the electrodeposition painting stage of automotive bodies, by providing nozzles for ejecting electrodeposition painting liquid at the bottom part on the outlet side of an electrodeposition painting tank and spraying the electrodeposition painting liquid to the recesses of the bodies. CONSTITUTION:An automotive body 3 is suspended with a hanger 2 and is moved in an arrow direction in the painting liquid 7 in an electrodeposition painting tank 4 by a conveyor 1, whereby the body is electrodeposition-painted. Many nozzles 9 for ejecting the painting liquid are provided at the bottom part on the outlet side of the tank 4, and the painting liquid is sprayed from the branch pipes 11 provided to the circulating pipe 10 for the liquid 7 toward the recesses such as fenders 3a of the body 3. The foam accumulating in the recesses is expelled by the injection of the painting liquid to spread the painting liquid over the entire part, whereby the entire part of the body is electrodeposition-painted thoroughly and uniformly.

Description

[Detailed Description of the Invention] Conventionally, for example, in applying a primer coat to the body of an automobile,
This is done by suspending the car body on a conveyor and transporting it by immersing it in an electrodeposition coating tank.

However, in a downwardly opening recess of a fender or the like, there is a drawback that air bubbles inevitably accumulate inside the recess and painting cannot be completed completely.

For this reason, a spray nozzle is installed near the bottom of the tank entry side of the electrocoating tank to eject the electrocoat liquid toward the recess, and the ejected electrocoat liquid collects inside the recess. An attempt to paint the inside of the recess by moving air bubbles was made in 1983.
This is proposed in Publication No. 32525 and the like.

However, it has been found that even if such a method is adopted, the expected effect cannot be obtained.

As a result of various studies on the reasons for this, the inventors of the present invention found that in electrodeposition coating, the coating starts from the parts with low electrical resistance with the electrode, and in the case of the car body, the painting starts from the outer surface of the car body outer panel, and then sequentially starts from the outer surface of the car body, etc. Even if the air bubbles in the recess are moved on the tank entry side as in the conventional example, electrodeposition coating has not yet been applied to this part at this time. Therefore, it was found that the effect was hardly exhibited.

The present invention has been made based on the above-mentioned knowledge, and its object is to provide a coating material located near the bottom of the outlet side of the electrocoating tank, below the object to be coated that is transported in the tank. A spray nozzle is installed to spray the electrodeposition paint liquid toward the object to be coated, and when the inside of the recess is being electrocoated, the electrodeposition paint liquid jetted from the jet nozzle moves the air bubbles inside the recess to generate electricity. To provide an electrodeposition coating device capable of performing electrocoating and completely electrocoating an object to be coated.

Next, the present invention will be explained according to the drawings which are one embodiment.

FIG. 1 is an explanatory diagram of the main parts of the electrodeposition coating apparatus of the present invention, in which 1 is a conveyor stretched above the electrodeposition coating tank 4;
A hanger 2 is attached to this conveyor 1, and a car body 3, which is the object to be painted, is suspended and immersed and conveyed from the entrance side (right side in the figure) to the exit side of the electrocoating tank 4. There is.

On the other hand, on the bottom 5 of the outlet side of the electrocoating tank 4, a paint liquid 7 is provided upwardly at a position facing the fender 3a of the vehicle body 3.
A pipe 8 is provided with a plurality of jet nozzles 9 for spouting out water, and this pipe 8 is provided with a circulation pipe 10 for guiding the paint liquid 7 from the overflow tank 6 and the paint liquid 7 from the bottom 5.
A branch pipe 11 from the pipe is connected.

The jetting nozzle 9 jets the paint liquid 7 toward the fender 3a by means of a circulation pump 12 provided in the circulation pipe 1o.

Specifically, as shown in FIGS. 2 and 3, the pipe 8 having the jet nozzle 9 is composed of a pair of pipes.

In addition to the pipe 8, a plurality of pipes 13 are provided at the bottom 5 of the electrodeposition coating tank 4 in parallel to the inside direction of the tank. Note that the pipe 13 is also connected to a circulation pipe (not shown) via a branch pipe 15. The lower surface of the pipe 13 has an ejection nozzle (not shown) for ejecting the paint liquid 7 downward and preventing the paint from settling, and the upper surface of the pipe from approximately the center of the electrocoating tank 4 to the outlet side. Each nozzle 14 is provided in a zigzag pattern to spray the paint liquid 7 upward, so that the air bubbles adhering to the floor of the vehicle body 3 are moved and painted.

Therefore, when the car body 3 is immersed in the paint solution 7 from the inlet side of the electrodeposition coating tank 4 and transported to the outlet side by the conveyor 1, the car body 3 is sequentially coated from the outside of the outer panel as described above. The fender 3a is painted, except for the inside of the fender 3a, and reaches the tank outlet side. When the vehicle body 3 comes to this position, the inside of the fender 3a receives the jet from the jet nozzle 9, and the fender 3a is painted. The air bubbles inside will be moved or expelled, during which time the inside of the fender will be completely painted.

Further, the jet nozzle 14 may be connected to the floor of the vehicle body 3. In the above embodiment, the vehicle body is used as the object to be painted, but the pipe 8 and the jet nozzle may be connected to the floor of the vehicle body 3 depending on the object to be painted. Of course, the arrangement of 9 may be changed.

As is clear from the above description, according to the present invention, the electrode is located near the bottom of the outlet side of the electrocoating tank, below the object to be coated that is being conveyed in the tank, and directed toward the object to be coated. Since the electrodeposition paint liquid is ejected from the ejection nozzle, even if the object to be coated has a recess etc. and air bubbles are present inside, the air bubbles will be effectively moved when painting this area. You can completely paint things.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram showing the main parts of the present invention, and FIG.
3 is a detailed sectional view on the outlet side of the figure, and FIG. 3 is a plan view of FIG. 2. 1...Conveyor, 3...Object to be coated, 4 Electrodeposition coating tank,
5. Bottom, 7. Paint liquid, 8. Pipe, 9. Spray nozzle.

Claims (1)

[Claims] (1) A jetting nozzle is provided near the bottom of the outlet side of the electrocoating tank, which is located below the object to be coated that is being conveyed in the tank, and which jets the electrodeposition coating liquid toward the object to be coated. An electrodeposition coating device characterized by: