JPH0461949A - Electrocoating device - Google Patents

Abstract

PURPOSE:To prevent an object to be coated from rocking due to the effect of a horizontal coating stream by a method wherein the horizontal coating stream in the upper part of a liq. electrocoating material is controlled to some extent while continuing the intended function in the circulation of the electrocoating material when the object is introduced in a tank. CONSTITUTION:Based on a signal from a valve 42, a liq. electrocoating material L is sprayed from a nozzle 4 to an object A when it is introduced into an electrocoating tank 1. The nozzle 4 is set in such a manner that the nozzle is inclined slightly downwardly to permit the liq. electrocoating material L to be sprayed, against the coating stream immediately before reaching a horizontal coating stream in the upper stream, of all the circulating streams in the tank of the liq. electrocoating material L. Therefore, even if the liq. electrocoating material L is sprayed from the nozzle 4 against the coating stream immediately before reaching the the horizontal stream when the object A is introduced into the tank, the horizontal stream is controlled by the liq. electrocoating material L.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electrodeposition apparatus, and more specifically, an electrodeposition tank that stores an electrodeposition solution in which a workpiece is immersed for electrodeposition coating.
The present invention relates to an electrodeposition apparatus that is provided with a liquid circulation means for causing the electrodeposition liquid to circulate in a tank so that the electrodeposition liquid becomes a horizontal flow at least in an upper layer thereof.

[Conventional technology]

In a conventional electrodeposition apparatus, a plurality of nozzles capable of spouting an electrodeposition liquid are usually installed at the bottom of the electrodeposition tank as the liquid circulation means.

By spouting the electrodeposition liquid from the nozzle, the electrodeposition liquid is caused to circulate in the tank in such a way that horizontal flows in opposite directions are created in the upper and lower parts, and based on the circulation in the tank, The aim was to prevent the settling of paint, eliminate bubbles that are disadvantageous to painting, improve painting efficiency, and improve the finish surface of the paint.

[Problem to be solved by the invention]

However, when performing electrodeposition using such an electrodeposition apparatus, the object to be coated is first immersed in the electrodeposition liquid in the electrodeposition tank, and when entering the bath, the object to be coated is immersed in the electrodeposition liquid. Affected by the circulation in the tank, more specifically, influenced by the horizontal flow of the electrodeposition liquid in the upper layer, it swings left and right or back and forth, and this comes into contact with the electrodeposition tank. Therefore, in the past, the electrodeposition tank was designed to be large and oversized to avoid the interference, but there was a problem in that increasing the size of the electrodeposition tank increased costs in various respects. For example, a larger electrodeposition tank itself is expensive, and a large amount of electrodeposition liquid is required to be stored in the electrodeposition tank, resulting in high costs.

The present invention has been made in view of the above circumstances, and eliminates the cost problem caused by over-designing the electrodeposition tank as described above by eliminating the effect of circulating the electrodeposition solution in the tank. The purpose of the present invention is to provide an electrodeposition device that can solve the problem without causing problems.

[Means to solve the problem]

The characteristic structure of the electrodeposition apparatus according to the present invention is such that the electrodeposition liquid flows horizontally in at least the upper layer of the electrodeposition tank, which stores the electrodeposition liquid in which the object to be coated is immersed for electrodeposition coating. An electrodeposition apparatus is provided with a liquid circulation means for causing the electrodeposition liquid to circulate in the tank, and the electrodeposition liquid is circulated in the tank in a state in which horizontal flow in the upper layer is suppressed; An upper flow switching means is provided for switching between a state where the horizontal flow is generated as it is, and
Its actions and effects are as follows.

[For production]

In the electrodeposition apparatus of the present invention, while continuing the circulation of the electrodeposition liquid in the tank, the upper flow switching means is used to suppress horizontal flow in the upper layer of the electrodeposition liquid when the object to be coated enters the tank. can do.

Further, according to the upper flow switching means, by switching the upper flow switching means, it is possible to directly generate a horizontal flow in the upper layer of the electrodeposition liquid.

〔Effect of the invention〕

Thus, according to the electrodeposition apparatus of the present invention, when the object to be coated enters the tank, the circulation of the electrodeposition liquid in the tank continues, and while the intended function of the circulation in the electrodeposition liquid tank continues to some extent, the electrodeposition liquid is By suppressing the horizontal flow in the upper layer of the coating, it is possible to suppress the swinging of the object to be coated due to the influence of the horizontal flow. Therefore, interference between the material to be mixed and the electrodeposition tank can be avoided without over-designing the electrodeposition tank.
This eliminates the conventional problem of having to over-design the electrodeposition tank.

Moreover, by switching the upper flow switching means, it is possible to directly generate a horizontal flow in the upper layer of the electrodeposition liquid, so that when the object to be coated enters the tank, the electrodeposition liquid does not flow outside the plate as before. Circulation within the tank is caused by horizontal flow in the upper layer, thereby maintaining the desired functions such as preventing paint from settling, eliminating bubbles that are detrimental to painting, improving painting efficiency, and improving the surface of the painted finish. It can be highly demonstrated.

The upper flow switching means may be a nozzle that spouts the electrodeposition liquid in the upper part of the electrodeposition tank so as to oppose the flow immediately before reaching the horizontal flow, and the liquid circulation means There are ways to reduce the circulation force in the tank.

In the case of the latter means, the horizontal flow of the electrodeposition liquid can be suppressed without providing many new devices and members.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

1 to 3 show an embodiment of the electrodeposition apparatus of the present invention, and (1) in the figures shows an electrodeposition tank.

In the electrodeposition tank (1), an electrodeposition liquid (L) is stored in which the object to be coated (A) (specifically, a car to be coated with the paint by electrodeposition) is immersed for electrodeposition coating. It has become so.

A hanger conveyor (3) is installed above the electrodeposition tank (1) for transporting the object to be coated (A) in a tactile manner in a suspended state. The hanger conveyor (3) transports the object to be coated (A) to a position above one end in the tank length direction of the electrodeposition tank (1), and lowers the object to be coated (A) at the position. This is immersed in the electrodeposition liquid (L), the object to be coated (A) is stopped in the immersed state, and after a predetermined period of time has elapsed, it is immersed in the electrodeposition liquid (L) in two steps. The object to be coated (A) immersed in the other end of the electrodeposition tank (1) is moved to the other end of the electrodeposition tank (1) by tact transport and held for a predetermined time. The object to be coated (A) that has been pulled up can be moved from above the electrodeposition bath (1) to another location.

A plurality of nozzles serving as the liquid circulation means (2) are installed at the bottom of the electrodeposition tank (1). More specifically, a plurality of nozzles (2) capable of spouting the electrodeposition liquid (L) in the electrodeposition tank (1) are arranged in parallel at predetermined intervals in the tank width direction, Moreover, they are also arranged in parallel at a predetermined interval in the moderate direction. The posture of the nozzle (2) is unified so that the opening direction of the nozzle is in a certain direction (slightly downward certain direction) substantially along the width direction of the tank.

The plurality of nozzles (2) have a circulation path (22) through which the electrodeposition liquid (L) is circulated and fed by the operation of a circulation pump (21).
) are connected to each other, and the electrodeposition liquid (L) fed through the circulation path (22) is spouted from the nozzle (2) into the electrodeposition tank (1). The electrodeposition liquid (L) has horizontal flows in opposite directions in the upper and lower parts of the electrodeposition tank (1), and upstream and downstream flows in opposite directions at the front and rear ends of the electrodeposition tank (1). (See the arrow in Figure 2).Based on this internal circulation, it is possible to prevent paint from settling, eliminate bubbles that are detrimental to painting, improve painting efficiency, and improve the finish of the paint. In this way, efforts are being made to improve the

Now, the electrodeposition tank (1) has a function for switching the state of circulation of the electrodeposition liquid in the tank between a state in which horizontal flow is suppressed in the upper layer and a state in which the horizontal flow is caused as it is. An upper flow switching means (M) is provided to perform the above function.Specifically, an electrodeposition liquid (L) serving as a medium for performing the above-mentioned function is placed in the electrodeposition bath (1) for the electrodeposition. A plurality of nozzles (4) are provided for ejecting water within the tank (1).

More specifically, a plurality of nozzles (4) are provided in the upper layer of the electrodeposition tank (1) and close to one side wall of the tank.
They are installed at predetermined intervals in the tank radial direction. Electrodeposition liquid (L) is supplied to the nozzle (4) via a branch path (41) branched from the circulation path (22). A valve ( 42 ) or intervening. Then, by the operation of the valve (42) based on the signal, the object to be coated (A) is emitted from the nozzle (4).
The electrodeposition liquid (L) is ejected into the electrodeposition tank (1) when the electrodeposition tank (1) enters the tank.

Moreover, the attitude of the nozzle (4) is such that the electrodeposition liquid (L) from its spout is in a flow immediately before reaching the horizontal flow in the upper layer of the circulation flow of the electrodeposition liquid (L) in the tank. They are set in a substantially downward-opening position so that they are ejected while facing each other. Therefore, when the object to be coated (A) is placed in the tank, as mentioned above,
Electrodeposition liquid (L) is ejected from the nozzle (4) so as to oppose the flow immediately before reaching the horizontal flow (see the white arrow in Fig. 1), and the ejected electrodeposition liquid (L) is (L)
The horizontal flow is suppressed by this. Incidentally, when the object to be coated (A) enters the tank, the valve (42) is closed to the outside of the plate, so that the electrodeposition liquid (L) is not spouted out, and the horizontal flow remains as it is.

Note that a nozzle support angle adjuster (44) is attached to the support portion of the nozzle (4). By using the nozzle support angle adjuster (44), the attitude of the nozzle (4) can be finely adjusted so that the function of the upper flow switching means (M) is fully exhibited. .

[Another example]

In the above embodiment, the upper flow switching means (M) was a nozzle (4) that spouted the electrodeposition liquid (L),
Other means may also be considered as the upper flow switching means (M). For example, a fourth
As shown in the figure, mechanical rocking is used to switch the circulation state of the electrodeposition liquid (L) in the tank between a state in which horizontal flow in the upper layer is suppressed and a state in which the horizontal flow is caused as it is. An embodiment in which a freely swinging plate (5) is installed may also be considered. In such an embodiment, the swinging plate (5) may be swung in an appropriate direction when the object to be coated (A) enters the tank. Therefore, the circulation flow of the electrodeposition liquid (L) in the tank can be interrupted immediately before it becomes the horizontal flow, thereby making it possible to suppress the horizontal flow.

Further, the upper flow switching means (M) includes the liquid circulation means (2) for suppressing the horizontal flow of the electrodeposition liquid (L).
A means for reducing the circulation force in the tank, more specifically,
It is conceivable to provide a device that can adjust the discharge force of the circulation pump (21) and reduce the internal circulation force in the tank by adjusting the device.

Further, as an embodiment of the present invention, the present invention may be applied to the case where horizontal flow is suppressed when the object to be coated is discharged from the tank.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the main parts of an electrodeposition apparatus according to the present invention, FIG. 2 is an overall side view of the electrodeposition apparatus, FIG. 3 is an overall plan view of the electrodeposition apparatus, and FIG. 4 is a main part of the electrodeposition apparatus. FIG. 7 is a side view of main parts showing another embodiment of the electrodeposition apparatus according to the invention. (1)...Electrodeposition tank, (2)...Liquid circulation means, (A)...Object to be coated, (L)...
Electrodeposition liquid, (M)...Upper flow switching means.

Claims (1)

[Scope of Claims] 1. In an electrodeposition tank (1) that stores an electrodeposition liquid (L) in which the object to be coated (A) is immersed for electrodeposition coating, at least the upper layer thereof contains the electrodeposition liquid. An electrodeposition apparatus comprising a liquid circulation means (2) for causing the electrodeposition liquid (L) to circulate in the tank so that the electrodeposition liquid (L) becomes a horizontal flow, the electrodeposition apparatus comprising: a tank for the electrodeposition liquid (L); An electrodeposition apparatus provided with an upper flow switching means (M) for switching the internal circulation state between a state in which horizontal flow in the upper layer is suppressed and a state in which the horizontal flow is directly generated. 2. The upper flow switching means (M) has a nozzle (4) that spouts the electrodeposition liquid (L) in the upper layer of the electrodeposition tank (1) so as to oppose the flow immediately before reaching the horizontal flow. ) The electrodeposition apparatus according to claim 1. 3. The upper flow switching means (M) is connected to the liquid circulation means (2
2. The electrodeposition apparatus according to claim 1, wherein the electrodeposition apparatus is a means for reducing the circulation force in the bath due to the above.