JP3079233B2 - 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 a method for discharging an electrolysis solution collected from a diaphragm device provided inside an electrodeposition tank to an electrolysis tank through an electrolysis solution discharge pipe, and adjusting the conductivity in the electrolysis tank. The present invention relates to an electrodeposition coating apparatus that supplies the obtained polar solution to the diaphragm device via a polar solution supply pipe by a pump.

[0002]

2. Description of the Related Art FIGS. 4 and 5 show a conventional electrodeposition apparatus. As is apparent from FIG. 4, acetic acid, lactic acid and acetic acid are contained in an electrodeposition tank 1 in which an object to be coated is immersed. The electrodeposition paint using formic acid (hereinafter, referred to as an electrode solution) as a solvent is filled.
On the inner side wall of the electrodeposition tank 1, a plurality of diaphragm devices 2 for keeping the pH of the electrodeposition paint constant are arranged. The diaphragm device 2 and an electrode solution tank 3 for adjusting the conductivity of the electrode solution are provided. Are connected by an anolyte discharge pipe 4 and an anolyte supply pipe 5. Extreme liquid discharge pipe 4
Is provided with a motor valve 6, and the polar liquid supply pipe 5 is provided with a pump 7, a motor valve 8 and a filter 9. The polar liquid tank 3 is connected to a pure water supply pipe 11 with a motor valve 10 interposed therebetween, and is provided with a stirring device 12 for stirring the internal polar liquid. And the polar liquid tank 3
Control panel 1 to which a signal from conductivity meter 13 provided in
4 controls the operation of the motor valve 10 provided on the pure supply pipe 11, the motor valve 6 provided on the anolyte discharge pipe 4, and the pump 7 and motor valve 8 provided on the anolyte supply pipe 5.

As is apparent from FIG. 5, a membrane device 2 provided inside an electrodeposition tank 1 in which an object to be coated W connected to a negative electrode is immersed, is capable of passing ions and low molecules, That is, there is provided a diaphragm container 16 partitioned by a diaphragm 15 through which paint particles cannot pass, and an electrode 35 made of ferrite covered with plastic is disposed inside the diaphragm container 16 in a state of being connected to the positive electrode. The polar liquid overflowing from the upper part of the diaphragm container 16 flows into the polar liquid discharge pipe 4, and the polar liquid from the polar liquid tank 3 is introduced into the lower part of the diaphragm container 16 by the polar liquid supply pipe 5. .

In the electrodeposition coating apparatus having the above configuration,
When the object W is immersed in the electrodeposition tank 1, the positively charged paint particles are sucked and applied to the object W connected to the negative electrode. On the other hand, the polar liquid ions contained in the electrodeposition paint are attracted by the electrode 35 connected to the positive electrode, pass through the diaphragm 15 and enter the inside of the diaphragm container 16, and from there, via the polar liquid discharge pipe 4, The liquid is discharged to the liquid tank 3. As described above, by discharging the amount of the anolyte ions corresponding to the amount of the paint particles adhering to the workpiece W, the PH of the electrodeposition paint in the electrodeposition tank 1 is prevented from changing, and Object W
This can avoid a problem that a skin defect occurs on the painted surface.

The polar liquid discharged to the polar liquid tank 3 through the polar liquid discharge pipe 4 is diluted with pure water supplied from the pure water supply pipe 11 and stirred by the stirrer 12. The detected conductivity is adjusted to an appropriate value. Thus, the polar liquid whose conductivity has been adjusted is supplied from the polar liquid supply pipe 5 to the diaphragm device 2 of the electrodeposition tank 1 by the pump 7. At this time, impurities contained in the polar liquid are filtered by a filter 9 provided in the polar liquid supply pipe 5.

[0006]

By the way, molds and bacteria are easy to grow inside the polar liquid tank 3, and the molds and bacteria also grow inside the electrodeposition tank 1 which is stopped after the production is completed. I do. Since these molds and bacteria cannot be removed even by the filter 9, the molds and bacteria circulating together with the polar liquid clog the diaphragm 15 of the diaphragm device 2, and as a result, the pH of the electrodeposition paint changes and the electrodeposition paint becomes uniform. There was a problem of inhibiting the formation of a film.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides an electrodeposition coating apparatus capable of reliably removing mold and bacteria contained in an electrode solution and preventing a deterioration in coating quality. With the goal.

[0008]

In order to achieve the above-mentioned object, the present invention is to discharge an anolyte collected from a diaphragm device provided inside an electrodeposition tank to an anolyte tank via an anolyte discharge pipe. In an electrodeposition coating apparatus for supplying the polar liquid whose electric conductivity has been adjusted in the polar liquid tank to the diaphragm device via a polar liquid supply pipe by a pump, a first opening / closing valve is provided in the polar liquid discharge pipe, downstream of the pump in the electrode liquid supply pipe, successively provided a cyclone device and a second on-off valve having an ultraviolet lamp inside, further between the cyclone device and the second on-off valve in the electrode liquid supply pipe branches the electrode liquid circulation pipe communicating with the electrode liquid vessel from between, on the electrode liquid circulation pipe, before
A third on- off valve independent of the first and second on-off valves is provided , and when the electrodeposition bath is used, the first and second on- off valves are used.
By opening the valve and closing the third on-off valve,
The polar liquid exiting the cyclone device is supplied to the diaphragm device.
And when the electrodeposition tank is not used,
Closing the second on-off valve and opening the third on-off valve
As a result, the polar solution exiting the cyclone device is
It is characterized in that the liquid is returned to the polar liquid tank via a pipe .

Further, the present invention provides, in addition to the first feature described above,
A plurality of the cyclone devices are connected in parallel between a first manifold connected to the upstream side of the polar liquid supply pipe and a second manifold connected to the downstream side, and a throttle valve and a flow meter are provided downstream of each of the cyclone devices. Are connected in series as a second feature.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 show an embodiment of the present invention. FIG. 1 is an overall configuration diagram of an electrodeposition coating apparatus, FIG. 2 is a longitudinal sectional view of a cyclone apparatus, and FIG. It is an arrow view.
In this embodiment, the same components as those of the above-described conventional electrodeposition coating apparatus are denoted by the same reference numerals, and the description that has already been described will be omitted.

As shown in FIG. 1, a first manifold 17 and a second manifold 18 are connected to the extreme liquid supply pipe 5 at a position downstream of the pump 7. Both manifolds 1
7 and 18 are arranged parallel and horizontal to each other, and three cyclone devices 19 are connected in parallel between them. A throttle valve 20 and a flow meter 21 are connected in series between each cyclone device 19 and the second manifold 18.

A sludge collection pipe 22 connected to the lower end of each cyclone device 19 is connected to a neutralization tank 24 having a stirring device 23.

From the second manifold 18 and the motor valve 8 in the polar liquid supply pipe 5, a polar liquid circulating pipe 25 connected to the polar liquid tank 3 branches, and a motor valve 26 is connected to the polar liquid circulating pipe 25. Provided.

As shown in FIGS. 2 and 3, the cyclone device 19 includes a main body casing 29 formed by connecting a cylindrical portion 27 whose upper end is closed and a conical portion 28 tapered downward. The inflow pipe 30 penetrates the cylindrical portion 27 so as to be eccentric with respect to the center line. The outer end of the inflow pipe 30 is connected to the first manifold 17, and the inner end thereof is formed to be flat in the left and right direction along the inner wall of the cylindrical portion 27, and curved slightly downward toward the conical portion 28. I do. A sludge discharge port 31 is provided at the lower end of the conical portion 28, and the discharge port 31 is connected to the sludge collection pipe 22.

A guide cylinder 32 having a lower end opened from the upper wall of the cylindrical portion 27 is provided vertically. The upper portion of the guide tube 32 opening 32 ₁ is formed, the inner end of the outlet pipe 33 penetrates the cylindrical portion 27 connected to the throttle valve 20 wherein it faces the opening 32 _1. An ultraviolet lamp 34 having a sterilizing effect is provided inside the guide tube 32.

As is apparent from FIG. 1, the control panel 14 includes, in addition to the aforementioned motor valves 6, 8, 10, the pump 7, and the conductivity meter 13, an ultraviolet lamp 34 of the cyclone device 19 and an anolyte circulation pipe. 25 motor valves 26 are connected.

Next, the operation of the embodiment of the present invention having the above configuration will be described.

When the electrodeposition tank 1 is used, the motor valve 6 of the polar liquid discharge pipe 4, the motor valve 8 of the polar liquid supply pipe 5, and the motor valve 10 of the pure water supply pipe 11 are opened, and the polar liquid circulation pipe 25 is opened. Motor valve 26 is closed. The polar liquid overflowing from the diaphragm device 2 of the electrodeposition tank 1 flows into the polar liquid tank 3 through the polar liquid discharge pipe 4, where it is supplied with pure water from the pure water supply pipe 11 and adjusted to an appropriate conductivity. After that, it is sent out to the polar liquid supply pipe 5 by the pump 7.
The polar liquid in the polar liquid supply pipe 5 flows into the first manifold 17 to make the pressure uniform, and then flows into the main casing 29 from the inlet pipes 30 of the three cyclone devices 19.

Since the inflow pipe 30 of the cyclone device 19 is tangentially connected to the cylindrical portion 27 of the main casing 29, the polar liquid rotates as a primary vortex inside the main casing 29. The primary vortex descends from the cylindrical portion 27 to the conical portion 28, and at this time, dead mold and bacteria and sludge contained in the polar liquid are discharged from the outlet 31 to the neutralization tank 24 via the sludge collection pipe 22. You. The primary vortex that has reached the lower end of the conical portion 28 rises as a secondary vortex along the outer periphery of the ultraviolet lamp 34 provided inside the guide tube 32, and at this time, live mold and bacteria contained in the polar liquid are exposed to ultraviolet light. Sterilized by the action of Secondary vortex reaching to the upper end of the guide tube 32 is discharged from the cyclone 19 through the opening 32 ₁ and the outflow pipe 33, and joins the second manifold 18 passes through the further throttle valve 20 and flow meter 21, which Is supplied to the membrane device 2 through the polar liquid supply pipe 5. At this time, by adjusting the opening of the throttle valve 20 based on the flow rate of the polar liquid detected by the flow meter 21, the amount of the polar liquid passing through the three cyclone devices 19 can be made uniform.

On the other hand, when the electrodeposition tank 1 is not used, the motor valve 6 of the polar liquid discharge pipe 4, the motor valve 8 of the polar liquid supply pipe 5, and the motor valve 10 of the pure water supply pipe 11 are closed. Only the motor valve 26 of the circulation pipe 25 is opened. When the pump 7 is driven in this state, the polar liquid in the polar liquid tank 3 passes through each cyclone device 19 of the polar liquid supply pipe 5 to remove mold and bacteria dead bodies and sludge, and then flows through the polar liquid circulation pipe 25. The liquid is returned to the polar liquid tank 3 through the tank.

In both the use and non-use cases of the electrodeposition tank 1, the polar liquid is circulated through the cyclone device 19 to completely remove mold and bacteria dead bodies and sludge. In addition, clogging of the diaphragm 15 of the diaphragm device 2 can be prevented. As a result, the conductivity of the polar solution is always maintained at an appropriate value, so that not only can the coating quality be prevented from deteriorating due to acidification of the polar solution, but also the service life of the diaphragm device 2 can be extended. Become.

Although the embodiment of the present invention has been described in detail, the present invention is not limited to the above-described embodiment, and various small design changes can be made.

[0024]

As described above, according to the first aspect of the present invention, a first on-off valve is provided in an anolyte discharge pipe,
Downstream of the pump in the liquid supply pipe , a cyclone device having an ultraviolet lamp and a second opening / closing valve are sequentially provided.
Between the cyclone device and the second on-off valve in the supply pipe
Branch off the polar liquid circulation pipe leading to the polar liquid tank.
A third independent pipe separate from the first and second on-off valves
When the electrodeposition bath is used, the first and second
By opening the on-off valve and closing the third on-off valve,
Electrolyte exiting the Ecron device is supplied to the diaphragm device
When the electrodeposition tank is not used, the first and second on-off valves
Cyclone by closing the valve and opening the third on-off valve
Electrolyte that has exited the device flows back to the electrolyte tank via the electrolyte circulation pipe
Since the way, when using the electrodeposition bath than the original, the unused
Even at times, the polar liquid in the polar liquid tank passes through the cyclone device.
And keep it circulating, so mold and
Sterilize the rear with ultraviolet light and remove the dead body and sludge.
The process of separating and removing from the polar liquid is effectively continued for a long time.
Therefore, it is possible to prevent the diaphragm of the diaphragm apparatus from being clogged and the conductivity of the anolyte in the electrodeposition tank from becoming excessive, thereby preventing the coating quality from being lowered. When the electrodeposition tank is not used
In a relationship permitting them to continue to circulate electrode liquid to the cyclone device through the electrode liquid circulation pipe there is, mosquito the electrode liquid tank
Because it can store clean polar liquid without
A clean polar solution can be supplied from the beginning of use of the electrodeposition tank.

According to the second feature of the present invention, a plurality of cyclone devices are connected in parallel between the pair of manifolds, so that the plurality of cyclone devices can increase the purification capacity of the polar liquid. . In addition, since the throttle valve and the flow meter are connected in series downstream of each cyclone device, the amount of the polar liquid flowing through each cyclone device can be adjusted to an optimum value.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an electrodeposition coating apparatus of the present invention.

FIG. 2 is a longitudinal sectional view of a cyclone device.

FIG. 3 is a view in the direction of arrows in FIG. 2;

FIG. 4 is an overall configuration diagram of a conventional electrodeposition coating apparatus.

FIG. 5 is a diagram showing an electrodeposition tank and a diaphragm device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrodeposition tank 2 Diaphragm apparatus 3 Electrolyte tank 4 Electrolyte discharge pipe 5 Electrolyte supply pipe 6 Motor valve (open / close valve) 7 Pump 8 Motor valve (open / close valve) 17 1st manifold 18 2nd manifold 19 Cyclone device 20 Throttle Valve 21 Flow meter 25 Electrolyte circulation pipe 26 Motor valve (open / close valve) 34 Ultraviolet light

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C25D 13/00, 13/24

Claims (2)

(57) [Claims] An anolyte collected from a diaphragm device (2) provided inside an electrodeposition tank (1) is discharged to an anolyte tank (3) via an anolyte discharge pipe (4). In the electrodeposition coating apparatus for supplying the polar liquid whose conductivity has been adjusted in the tank (3) to the diaphragm device (2) via the polar liquid supply pipe (5) by a pump (7), with the first on-off valve provided (6)), the downstream of the pump (7) in the electrode liquid supply pipe (5), the cyclone device (19) and the second with a ultraviolet lamp (34) therein An on-off valve (8) is provided in order, and furthermore, an electrode communicating between the cyclone device (19) and the second on- off valve (8) in the extremely liquid supply pipe (5) to the extremely liquid tank (3). The liquid circulation pipe (25) is branched, and the first and second liquid circulation pipes (25)
A third on- off valve (2 ) independent of the on-off valves (6, 8)
6), and when the electrodeposition tank (1) is used, the first and second on-off valves are used.
Open (6, 8) and close the third on-off valve (26)
The polar liquid exiting the cyclone device (19)
Is supplied to the diaphragm device (2), and
When the tank (1) is not used, the first and second on-off valves
Close (6, 8) and open the third on-off valve (26)
As a result, the polar liquid leaving the cyclone device (19) is
Refluxed to the anolyte tank (3) via the anolyte circulation pipe (25)
Characterized in that the so that, electrodeposition coating device. 2. A first manifold (17) connected to an upstream side of the polar liquid supply pipe (5) and a second manifold (17) connected to a downstream side.
The cyclone device (1) is connected to the manifold (18).
The electrodeposition coating according to claim 1, characterized in that a plurality of (9) are connected in parallel, and a throttle valve (20) and a flow meter (21) are connected in series downstream of each cyclone device (19). apparatus.