JP2550003Y2 - Electrocoating equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrodeposition coating apparatus often used for painting automobiles and the like.

[0002]

2. Description of the Related Art As shown in FIG. 1, a recent general electrodeposition tank is provided with a paint circulation system 3 between an overflow tank 2 on the outlet side. That is, a plurality of risers 6
The electrodeposition paint is disposed near the bottom of the electrodeposition tank 1 at an appropriate interval with the ejection port facing the tank wall on the entry side, and the electrodeposition paint overflowing into the overflow tank 2 is removed by the operation of the pump 4. Tank 2
The system is provided with a piping system in which the electrodeposition paint is collected and filtered by the filter 5 and then fed to each riser 6 of the electrodeposition tank 1. (See Japanese Utility Model Laid-Open No. 3-1971).

[0003] In the electrodeposition coating, in the state where the electrodeposition paint circulates between the electrodeposition tank 1 and the overflow tank 2, an object 20 such as an automobile body is charged on the entry side. This is carried out by immersing in the bath 1 and carrying it in the direction of the arrow x while being immersed below the liquid level h, and lifting it up on the outlet side.

[0004] In such electrodeposition coating, a coating liquid as shown by an arrow p in FIG. 1 enters the electrodeposition tank 1 from the outlet side at the bottom of the tank by jetting paint from risers 6. It flows to the tank side, then reverses on the inlet side, and in the surface layer forms a circulating flow that flows from the inlet side to the outlet side.

[0005] The formation of such a circulating flow p can prevent the sedimentation and aggregation of the electrodeposition paint, and facilitate the escape of gas generated from the surface of the article to be coated entering the tank to the outside air. The effect that the foam in the layer can be sent to the overflow tank 2 is obtained.

[0006]

However, the conventional electrodeposition coating apparatus described above still has the following problems. With the arrangement of the risers 6 with the jet ports directed toward the entrance side, during operation, two or three vortices q as shown in FIG. 1 are easily formed near the surface layer on the exit side, and Debris, dust, and the like in the electrodeposition tank 1 collect there, and stay with the coating liquid in the vortex q for a long time. Therefore, the concentration of butterflies and the like in the outlet area increases, which may increase the occurrence of coating film defects in the electrodeposition coated product.

As a countermeasure against this, conventionally, as shown in FIG. 1, a riser 7 is provided at the position closest to the outlet of the electrodeposition tank 1 with the injection port directed upward, thereby canceling the vortex q. A method of forming the flow separately has also been adopted.

However, even if this method is adopted, the swirl q disappears, but another swirl q 'is newly formed below the swirl q, and dust and dirt are generated in the discharge area. The situation of concentration remains unsolved. Therefore, the above method is not a fundamental solution.

The present invention has been made in view of such circumstances, and its purpose is to suppress the generation of eddy currents near the surface layer on the outlet side and to eliminate the concentration of dust and debris in the outlet area. An object of the present invention is to provide an electrodeposition coating apparatus capable of performing the above-mentioned.

[0010]

In the electrodeposition coating apparatus according to the present invention, an overflow tank is provided on the outlet side of the electrodeposition tank, and a plurality of risers are directed to the bottom of the electrodeposition tank toward the entrance side. The electrodeposition paint is collected from the overflow tank, filtered, and then, after being filtered from the riser, the eductor is connected to the electrodeposition tank in the electrodeposition coating apparatus provided with a paint circulation system which is ejected from the riser and resupplied to the electrodeposition tank. It is characterized in that it is attached to a wall on the outlet side so as to communicate with the inside of the overflow tank, or a slit is formed in a side wall between the electrodeposition tank and the overflow tank.

The present invention is an improvement of a recent general electrodeposition coating apparatus as shown in FIG. Therefore, the electrodeposition coating apparatus according to the present invention has the basic configuration of the conventional apparatus, and further includes an eductor or a slit.

The eductor and the slit are provided at a position below the coating liquid level of the electrodeposition tank. The eductor may be any configuration as long as it sucks the electrodeposition paint in the outlet area of the electrodeposition tank from around the central nozzle and ejects the paint through the side wall of the outlet area into the overflow tank. In this case, the electrodeposition paint in the outlet region may be configured to flow into the overflow tank.

[0013]

In the conventional general apparatus as described above, a large amount of electrodeposition paint always overflows from the electrodeposition tank to the overflow tank during operation due to the operation of the paint circulation system.

In the present invention, in parallel with the overflow flow, by mounting an eductor or forming a slit, a considerable amount of the electrodeposition paint is supplied from the lower part of the liquid level in the outlet area of the electrodeposition tank to the side wall of the electrodeposition tank. Flows out into the overflow tank via. Therefore, the generation of a vortex near the surface layer in the outlet region is eliminated.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings.

The electrodeposition coating apparatus of the embodiment is an apparatus used for electrodeposition coating of a body in a coating factory such as an automobile, and the apparatus of any of the embodiments has a general configuration as shown in FIG. It is the same as a typical electrodeposition coating apparatus. That is, the present apparatus has an electrodeposition tank in which a plurality of risers are arranged at the bottom of the tank toward the entry side, an overflow tank provided alongside the exit side, and an electrodeposition coating material between the two tanks. A system for performing circulation is provided. The paint circulation system includes pumps, filters, valves, and the like in addition to piping.

Embodiment 1 As shown in FIG. 2A, the device of this embodiment
Is formed in the side wall 8 on the outlet side of the electrodeposition tank 1, and the eductor 10 is attached to the hole 9 so as to communicate with the inside of the overflow tank 2.

When the eductor 10 is attached, during operation, the electrodeposition paint in the lower part of the liquid level in the outlet area is sucked in from around the central nozzle and jetted into the overflow tank 2 through the side wall 8. Accordingly, in parallel with the overflow flow 21, a considerable amount of the electrodeposition paint flows out of the outlet area of the electrodeposition tank 1 into the overflow tank 2, thereby generating a vortex near the surface layer of the outlet area. Concentration of butter etc. was eliminated.

Embodiment 2 In the apparatus of this embodiment, as shown in FIG. 2B, several slits 11 are formed in the side wall 8 between the electrodeposition tank 1 and the overflow tank 2.

During operation, the formation of the slits 11
In parallel with the overflow flow 21, a considerable amount of the electrodeposition paint flows out of the part below the liquid surface in the outlet area of the electrodeposition tank 1 into the overflow tank 2.
The generation of eddy currents near the surface layer in the outlet region was eliminated, and the concentration of butter and the like was eliminated.

[0021]

As described above, in the electrodeposition coating apparatus according to the present invention, during operation, the electrodeposition paint in the outlet area of the electrodeposition tank is operated in parallel with the overflow flow through the side wall of the electrodeposition tank. Since it is made to flow into the overflow tank, eddy currents are not generated near the surface layer in the outlet area, so that it is possible to suppress the concentration of dust and debris in the outlet area, and therefore, for electrodeposition coating products The occurrence of coating film defects can be further reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a general structure of an electrodeposition coating apparatus according to the present invention.

FIG. 2 is an enlarged view showing a main part of the electrodeposition coating apparatus according to the embodiment of the present invention. FIG. 2A shows a main part of the apparatus of the first embodiment, and FIG. 2B shows a main part of the apparatus of the second embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 electrodeposition tank 2 overflow tank 3 paint circulation system 4 pump 5 filter 6 riser 7 riser (having upward ejection port) 8 side wall 10 eductor 11 slit p paint circulation q q 'vortex h liquid level

Claims (2)

(57) [Scope of request for utility model registration] 1. An overflow tank is provided adjacent to the outlet side of an electrodeposition tank, and a plurality of risers are disposed at the bottom of the electrodeposition tank toward the inlet side to collect electrodeposition paint from the overflow tank. In the electrodeposition coating apparatus provided with a paint circulation system which, after filtering, is ejected from the riser and resupplied to the electrodeposition tank, the eductor communicates with the inside of the overflow tank to a wall on the outlet side of the electrodeposition tank. An electrodeposition coating apparatus characterized by being attached to 2. An overflow tank is provided adjacent to the outlet side of the electrodeposition tank, and a plurality of risers are arranged at the bottom of the electrodeposition tank toward the inlet side to collect the electrodeposition paint from the overflow tank. In the electrodeposition coating apparatus provided with a paint circulation system which, after filtering, is ejected from the riser and resupplied to the electrodeposition tank, a slit is formed in a side wall between the electrodeposition tank and the overflow tank. Electrodeposition equipment.