JPH0450910Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a conductive paint color changing coating device that performs electrostatic coating by changing the colors of conductive paints of a plurality of colors.

[Conventional technology]

Conventional color change painting equipment is equipped with a number of color change valves corresponding to the number of paint colors that may be changed, and these color change valves are connected to all paint tanks that serve as supply sources for each color paint. There is something connected to it.

However, in this case, the number of color change valves becomes extremely large, and the number of pipes such as paint supply pipes connected between each color change valve and each paint tank becomes enormous, resulting in a significant equipment cost. There are disadvantages such as bulkiness and installation space.

For this reason, there are cases where high equipment costs cannot be incurred,
If the installation space is small, for example, as shown in Figure 2, two color change valves CV ₁ and CV ₂ may be installed in a first manifold 3 connected to an electrostatic sprayer 1 via a paint hose 2. Provided with one color change valve CV ₁
While the paint tank 4W for the previous color paint connected to the other color change valve CV 2 is opened and the next color paint is being applied, the paint tank 4W for the previous color paint connected to the other color change valve CV ₂ is connected to the paint tank 4W for the different color paint to be applied after the next color paint. A color change coating device designed to replace tank 4R is used.

By the way, when color changing painting is performed on objects to be painted that are continuously conveyed by a conveyor, it is required that the color changing time of the paint be as short as possible. At the same time, the valve CV ₂ is switched to the paint discharge system 5, and the on/off valve 6 installed in the paint discharge system 5 is opened to wash and remove the previous color paint remaining in the paint supply pipe 7. The air and solvent supplied from the cleaning air supply source 10 and cleaning solvent supply source 11 through the air supply piping 12a and the solvent supply piping 13a, respectively, are alternately opened and closed. The previous color paint remaining in the manifold 3, the paint hose 2, and the electrostatic atomizer 1 is discharged from the electrostatic atomizer 1 to be washed and removed.

Here, the inside of the paint supply pipe 7 is cleaned by alternately opening and closing the air supply valve 15 and the solvent supply valve 16 provided in the second manifold 14 connected to the pipe 7, and the cleaning air supply source 10 and the solvent supply valve 16 are alternately opened and closed. This is carried out by alternately supplying air and solvent from the cleaning solvent supply source 11 through the air supply pipe 12b and the solvent supply pipe 13b, respectively.

At the same time, the second manifold 14
Switch the paint supply valve 17 installed in the paint supply pipe 7 from the paint supply system side to the paint discharge system 18 side, open the on/off valve 19 installed in the paint discharge system 18, and open the paint tank. 4W is replaced with a solvent tank 20, and the solvent in the solvent tank 20 is pumped by a pump 22 interposed in a paint supply pipe 21 leading to a paint supply valve 17 to remove the previous color paint remaining in the paint supply pipe 22. is discharged to the paint discharge system 18.

After cleaning the previous color paint in this way,
First, replace the solvent tank 20 with the paint tank 4 of different color paint.
R, the paint in the paint tank 4R is pumped by the pump 22, and the solvent remaining in the paint supply pipe 21 is forced out to the paint discharge system 18 by the pressure of the paint.

When the solvent is completely discharged from the paint supply pipe 21, the on/off valve 19 is closed, and at the same time, the paint supply valve 17 is switched from the paint discharge system 18 side to the paint supply system side, and the paint tank 4R
The different color paint is supplied under pressure from the manifold 14 and the paint supply pipe 7 to the color change valve CV ₂ , and when the paint supply pipe 7 is completely filled with paint, the on/off valve 6 is closed and the next color is changed. Wait until the paint is finished.

As a result, the time required to change the color from the next color paint to the different color paint becomes extremely short.

[Problem that the invention attempts to solve]

However, the color change coating device shown in FIG.
Although it has the advantage of being able to shorten the color change time as described above, it has the disadvantage of not being able to use conductive paints such as water-based paints.

In other words, a high voltage of 80KV to 120KV applied to the electrostatic coating machine 1 that is applying the conductive next color paint is applied to the first manifold 3 through the coating hose 2.
leaks from the manifold 3 to the second manifold 14 through the paint supply pipe 7, air supply pipes 12a and 12b or solvent supply pipes 13a and 13b, and further leaks from the manifold 14 to the paint tank 4 through the paint supply pipe 21.
Since the paint tank 4W is replaced with the solvent tank 20 or the paint tank 4R, there is a risk of electric shock.

In order to prevent this, it is necessary to make the paint hose 2 insulating, or to make each pipe 7, 12 connected between the first manifold 3 and the second manifold 14
Although it is necessary to use insulating piping for a and 12b and 13a and 13b, this alone cannot avoid the risk of electric shock.

This is because the high voltage leaked to the first manifold 3 through the conductive paint in the paint hose 2.
This is because the solvent leaks to the second manifold 14 through the solvent in the solvent supply pipes 13a and 13b, and further leaks from the manifold 14 to the paint tank 4W and the solvent tank 20 through the conductive paint and solvent in the paint supply pipe 21. .

Therefore, the present invention can reliably prevent the risk of the high voltage applied to the electrostatic coating machine leaking through the conductive paint and solvent piping system to the paint tank 4W and solvent tank 20 that are replaced when changing colors. The purpose of the present invention is to provide a color changing coating device for conductive paint.

[Means for solving problems]

To achieve this objective, the present invention supplies conductive paint of each color, which is supplied from a paint tank through an insulating paint supply pipe, to a first manifold connected to an electrostatic sprayer through a paint hose. A plurality of color change valves to be selected are provided, and while the color is changed from the previous color paint to the next color paint by switching the color change valve, and the paint of the next color paint is being painted, the paint supply piping for the previous color paint is The color changing coating device for conductive paint is configured to clean the paint supply pipe and fill the paint supply pipe with a different color paint, wherein a second manifold is connected to the paint supply pipe, and the second manifold is connected to the second manifold. The paint supply valve connects the insulating paint supply piping connected to the paint tank to the paint supply system and paint discharge system, and the cleaning air supply source and cleaning solvent supply via the air/solvent selection valve. The air/solvent supply valve is provided with an air/solvent supply valve that is switchably connected to the source, and the air/solvent supply valve and the air/solvent selection valve are connected by an insulating pipe.

[Effect]

According to the present invention, when cleaning the previous color paint, the air/solvent supply valve provided in the second manifold and the air/solvent supply valve connected to the air/solvent supply valve via insulating piping are used. The selection valve is opened and closed, and air and solvent are alternately supplied to the paint supply pipe connected between the first manifold and the second manifold, and the previous color paint remaining in the paint supply pipe is removed. Washed and removed.

At this time, if air and solvent are selectively supplied to the paint supply pipe in the order of air-solvent-air, the conductive paint and solvent will be discharged from inside, and the paint supply pipe will become a complete insulator. The solvent is also discharged from the insulating pipe connected between the air/solvent selection valve and the air/solvent supply valve, and the insulating pipe becomes a complete insulator.

As a result, the first manifold and the second manifold are electrically disconnected, and the high voltage applied to the electrostatic atomizer that is applying the next color of paint leaks into the paint tank of the previous color. Because you won't
At this time, the paint tank can be safely replaced.

〔Example〕

Hereinafter, embodiments of the present invention will be specifically described based on the drawings.

FIG. 1 is a flow sheet diagram showing an example of a color change coating apparatus according to the present invention.

Note that parts common to those in FIG. 2 described above are given the same reference numerals and detailed explanations are omitted.

In FIG. 1, an insulating paint supply pipe 21 connected to the paint tank 4W is connected to the second manifold 14.
A paint supply valve 17 that connects the paint supply system to the paint supply pipe 7 and a paint discharge system 18 that leads to the waste liquid tank 23, an air supply pipe 12b connected to the cleaning air supply source 10, and a cleaning solvent supply. Air is connected to the solvent supply pipe 13b connected to the source 11.
An air/solvent supply valve 25 is provided, which is switched and connected via a solvent selection valve 24.
Solvent supply valve 25 and air/solvent selection valve 24
and are connected by an insulating pipe 26.

Here, the air/solvent selection valve 24 is formed as a three-way valve having two inflow ports connected to the air supply pipe 12b and the solvent supply pipe 13b, and an outflow port connected to the pipe 26.

Further, the paint tank 4W is supported by an insulator 27.

Therefore, when cleaning the inside of the paint supply pipe 7 where the previous color paint remains while painting the next color paint,
The air/solvent supply valve 25 provided in the second manifold 14 is opened, and the air/solvent supply valve 25 connected to the valve 25 via an insulating pipe 26 is opened.
By switching the solvent selection valve 24, the air supply pipe 12b connected to the cleaning air supply source 10 is
Air and solvent are alternately supplied to the paint supply pipe 7 in the order of air-solvent-air, respectively, which are pumped from the solvent supply pipe 13b connected to the cleaning solvent supply source 11.

As a result, first, the previous color paint remaining in the paint supply pipe 7 is forced out to the paint discharge system 5 by the air pressure, and then the previous color paint adhering to the inner wall of the pipe 7 is pushed out by the solvent. washed away, and finally,
The solvent remaining in the pipe 7 and the insulating pipe 26 is forced out to the paint discharge system 5 by the air pressure.

Therefore, the inside of the insulating paint supply pipe 7 and the inside of the pipe 26 are in a state where the conductive paint and solvent are extracted, and the high voltage applied to the electrostatic atomizer 1 passes through the next color paint being painted. The leaking first manifold 3 and the second manifold 14 are completely insulated.

In this state, the paint supply valve 17 provided in the second manifold 14 is switched from the paint supply system side leading to the paint supply pipe 7 to the paint discharge system 18 side, and the on/off valve installed in the paint discharge system 18 is switched. At the same time as opening the off valve 19, the paint tank 4W is removed and replaced with the solvent tank 20, and the solvent in the solvent tank 20 is pumped by the pump 22 interposed in the paint supply pipe 21 leading to the paint supply valve 17. The previous color paint remaining in the paint supply pipe 22 is discharged to the paint discharge system 18.

Once the previous color paint has been cleaned in this way,
First, replace the solvent tank 20 with the paint tank 4 of different color paint.
R, the paint in the paint tank 4R is pumped by the pump 22, and the solvent remaining in the paint supply pipe 21 is forced out to the paint discharge system 18 by the pressure of the paint.

By doing the above, the paint tank 4W for the previous color paint
When replacing the solvent tank 20 with the solvent tank 20, or when replacing the solvent tank 20 with the paint tank 4R of a different color paint that will be used next.
There is no risk of the worker receiving an electric shock when replacing the product.

When the solvent is completely discharged from the paint supply pipe 21, the on/off valve 19 is closed, and at the same time, the paint supply valve 17 is switched from the paint discharge system 18 side to the paint supply system side, and the paint tank 4R
The different color paint is supplied under pressure from the manifold 14 and the paint supply pipe 7 to the color change valve CV ₂ , and when the paint supply pipe 7 is completely filled with paint, the on/off valve 6 is closed and the next color is changed. Wait until the paint is finished and prepare for the next color change quickly.

In addition, in the above embodiment, the paint tank 4W
A pump 22 pumps the paint inside and the solvent inside the solvent tank 20.
Although the case of pressure feeding has been described, the present invention is not limited to this, and the present invention may also be a case where the paint tank 4W or the like is used as a pressurized tank and the paint etc. is pumped by air pressure without using the pump 22.

[Effect of idea]

As described above, according to the present invention, while the next color paint is being applied by the electrostatic coating machine,
When quickly changing colors by replacing a paint tank containing the previous color with a paint tank containing a different color, even if the paint used is conductive, the high voltage applied to the electrostatic sprayer may Since there is no leakage of the conductive paint or solvent into the paint tank of the previous color paint, there is an excellent effect that the paint tank can be replaced safely.

[Brief explanation of the drawing]

FIG. 1 is a flow sheet diagram showing an example of a color change coating apparatus according to the present invention, and FIG. 2 is a flow sheet diagram showing a conventional apparatus. Explanation of symbols, CV ₁ , CV ₂ ...Color change valve, 1...
...Electrostatic sprayer, 2...Paint hose, 3...First manifold, 4W...Paint tank for previous color paint,
4R... Paint tank for different color paint, 7... Paint supply piping, 10... Cleaning air supply source, 11... Cleaning solvent supply source, 14... Second manifold, 1
7...Paint supply valve, 18...Paint discharge system, 2
0...Solvent tank, 21...Paint supply pipe, 24...
...Air/solvent selection valve, 25...Air/solvent supply valve, 26...Insulating piping.

Claims (1)

[Scope of utility model registration request] A first manifold connected to the electrostatic paint sprayer via a paint hose is provided with a plurality of color change valves for selecting each color of conductive paint supplied from the paint tank through the insulating paint supply piping. The color is changed from the previous color paint to the next color paint by switching the color change valve, and while the next color paint is being painted, the paint supply pipe for the previous color paint is cleaned and the different color paint is applied to the paint supply pipe. A second manifold is connected to the paint supply pipe, and the second manifold has an insulating paint connected to a paint tank. A paint supply valve that selectively connects the supply pipe to a paint supply system and a paint discharge system, and an air/solvent supply valve that selectively connects the supply pipe to a cleaning air supply source and a cleaning solvent supply source via an air/solvent selection valve. 1. A color changing coating device for conductive paint, characterized in that the air/solvent supply valve and the air/solvent selection valve are connected by an insulating piping.