JPH0910640A - Painting booth for water base paint - Google Patents

Abstract

PURPOSE: To improve the recovery efficiency of an overspray coating material and to shorten the coating work stopping time interval due to color change by integrating the parts which are hard to be cleaned and in which a remaining coating material is hard to be confirmed such as a suction duct, a filter, and a pump, piping and the like in a circulating recovery system and constituting a portable replacement unit of each color of the integrated body. CONSTITUTION: A painting booth for water base paint is constituted of a washing booth 20, a replacement unit of each color 21, and a suction duct 22. The replacement unit 21 is constituted as a portable one by mounting a waste gas washing chamber 24 and a recovery device 25 on a truck 23. The unit 21 is constituted so that it can freely attachably and detachably be connected to a washing water discharge port of the washing booth 20 and a suction port of the suction duct 22 to easily perform replacement on color change. Thus parts having complicated structure hard to be cleaned are replaced by the change unit 21 in a batch, allowing the cleaning on color change to be restricted to cleaning and movement of the washing booth 20 and the suction duct 22 only, permitting color change to be made easy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-based paint coating booth in which a multi-color water-based paint is applied so as to be recoverable and the color can be easily changed in a short time.

[0002]

2. Description of the Related Art A water-based paint is a resin composition in which a resin component is dispersed in water as an emulsion. Since no organic solvent is used, there is no need to worry about environmental pollution. Became used. The water-based paint can be applied by a method similar to that of the conventional solvent-based paint, and spray painting is generally performed.

[0003] In spray coating, an object to be coated (hereinafter referred to as "work") is passed through a spray gun pattern. For uniform coating, the pattern range needs to be larger than the work size. The distance between workpieces,
Due to the gap of the work itself (for example, a lattice-like thing), the application efficiency of the paint by spraying is extremely low depending on the shape of the work. In this way, the paint that is oversprayed without being applied to the work adheres to the gun-facing wall of the painting booth and accumulates, or is discharged to the outside as mist during exhaust.

The washing booth is intended to prevent the booth walls and exhaust air from being contaminated by such overspray paint, and the washing water flows on the wall of the painting booth or the exhaust duct to form a water film. The paint mist is washed and collected together with washing water in a tank provided at the lower part of the booth, and the paint in the washing water is separated as a solid content and discarded. However, in the case of the water-based paint, since the solvent of the paint and the washing water are the same water, the paint is simply diluted without being separated as a solid content in the wash water. From this, if the emulsion diluted in the washing water is concentrated by ultrafiltration, it can be reused as a paint, and the filtrate can be reused as fresh washing water.

FIG. 5 shows a main structure of a conventional water-based paint coating booth capable of collecting the overspray paint as described above. Work 1 is conveyor 2
Is hung on a hanger 3 and sprayed by a spray gun 5 while passing through a coating booth 4. A plurality of spray guns 5 are arranged side by side according to the shape and size of the work 1, and reciprocate up and down as necessary, so that the paint in the paint tank 6 is uniformly sprayed on the work 1. The air in the coating booth 4 is exhausted from the lower part of the booth through the suction duct 7 by the exhaust fan 8. A shower nozzle 411, 711, 71 in which a plurality of nozzles are arranged in a row is provided on each of the gun-facing wall surface 401 of the coating booth 4 and the wall surfaces 701, 702 of the suction duct 7.
2 is attached, a water film is formed on the wall surface by flowing washing water, the overspray paint is washed, and a liquid pool 9 at the bottom is formed.
Flow down. The height of the liquid level is kept constant, and the excess washing water is stored in a storage tank 10 below,
From here, it is circulated to the shower nozzle via the circulation pump P1.

[0006] The washing water in the storage tank 10 is also sent to a collecting tank 11 provided for each color by a pump P2, and passed through an ultrafilter (UF) 12 under a predetermined pressure by a pump P3. The paint is concentrated and returned to the recovery tank 11 again. The recovered paint concentrated by this circulation filtration is
It is added to the paint tank 6 and reused. Further, the water separated by the ultrafilter 12 is stored in the filtrate tank 13 and is supplied as fresh washing water from the pump P4 through the shower nozzle 411,
711 and 712.

[0007]

As described above, in the case of the water-based paint, the overspray paint can be recovered from the washing water to improve the paint yield, and the filtrate can be separated and reused. Can also be reduced. On the other hand, when the color of the paint is changed, the paint tank 6 and the recovery tank 11 are replaced for each color. However, if the booth, the duct and the entire circulating recovery system are not sufficiently cleaned, the recovered paint may be mixed and used. Disappears. Cleaning at the time of color change including such a recovery system requires at least one to two hours, during which time the next coating operation must be stopped. Furthermore, the filtration of the emulsion by ultrafiltration takes time, and the capacity of the filter needs to be extremely large in order to balance the process with the coating speed.

SUMMARY OF THE INVENTION The present invention has been made for the above-mentioned reasons, and an object of the present invention is to provide a coating booth capable of efficiently collecting oversprayed paint, and to reduce the time for stopping the painting work due to the color change of the paint. It is an object of the present invention to provide a water-based paint coating booth that can be shortened.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a water-based paint coating booth which uses a multicolor paint so that it can be recovered, and an object of the present invention is to provide a washing water outlet and a suction duct at the bottom of the washing booth. A cleaning chamber is provided detachably between the suction port and the cleaning chamber for introducing the discharged cleaning water and cleaning the mist contained in the exhaust gas, and collected and circulated in a cleaning tank at the bottom of the cleaning chamber. A concentration tank that pumps up and stores a part of the washing water for washing the booth, an ultrafilter that concentrates the liquid stored in the concentration tank by ultrafiltration, and returns the liquid to the concentration tank again; This is attained by providing an exchange unit in which a filtrate filtered from the ultrafilter is stored and a filtrate tank that supplies the filtrate as fresh washing water is mounted on a trolley for each color of paint used. .

[0010]

[Function] Although water-based paints are easy to wash with water, it is necessary to manually clean areas where washing water does not reach when changing colors.
In places that cannot be seen and are out of reach, especially in suction ducts where collision plates are installed to trap paint mist in exhaust air, pumps and piping for filter and circulation recovery systems, etc. It is difficult to confirm the presence or absence, and cleaning takes time. In the present invention, the above-mentioned parts are integrated into a portable replacement unit for each color, and when changing colors, only the replacement of the unit and cleaning of the booth which is easy to clean may be performed, and the time required for the replacement is 10 to 15 minutes. And the downtime of the painting operation is greatly reduced.

Further, in the present invention, since the exchange unit includes a collection device dedicated to each color, the collection operation can be continued even off-line, so that it is not necessary to balance the process with the coating. The capacity of the filter can be reduced.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an example of the overall configuration of a water-based paint coating booth according to the present invention, which comprises a water-washing booth 20, an exchange unit 21 for each color, and a suction duct 22. The exchange unit 21 includes a cart 23 as described later.
A washing chamber 24 for exhaust gas and a recovery device 25 are mounted on the washing bath 20.
Are detachably connected to the suction ports, respectively, so that they can be easily replaced when changing colors. These joints are performed using flange joints. The flanges on the side of the washing booth 20 and the suction duct 22 are each provided with a plurality of cylinders 2.
Sleeve 2 that slides in the vertical direction by driving 6, 27
The flanges are attached to the lower ends of the units 8 and 29, and when the replacement unit 21 is replaced, these flanges are raised, and when the unit is joined, the flanges are lowered so as to abut on the unit-side flange to be fixed.

FIG. 2 is a block diagram of the replacement unit 21, and FIG. 3 is a sectional view for explaining the internal structure of the cleaning chamber 24. The cleaning chamber 24 is formed using a plastic material such as polypropylene, hard vinyl chloride, and acrylic resin, and the internal structure is shown in FIG. The washing water discharged from the washing booth 20 flows down in the room separated by the partition plate 30 and the washing tank 3 at the bottom of the washing room 24.
It is stored in 1. The liquid level is adjusted so as to leave a slight gap with the lower end of the partition plate 30. And
Exhaust from the washing booth 20 containing paint mist is sucked into the washing chamber at a high speed through this gap, and comes into contact with the liquid surface by a plurality of collision plates 321 and 322 provided therein, whereby the paint mist is captured. And falls into the cleaning tank 31. When the liquid level of the cleaning tank 31 reaches a predetermined height, as shown in FIG. 2, excess cleaning liquid is sent to the concentration tank 33 by the pump P2 and stored. When the liquid in the cleaning tank 31 is insufficient, it is replenished from the concentration tank 33. In such a state,
The washing water in the washing tank 31 is circulated and supplied to the shower nozzle 411 in the washing booth 20 by the circulation pump P1.

Further, the liquid stored in the concentration tank 33 is applied with a predetermined pressure by a pump P3 and filtered while passing through an ultrafilter 34 to be separated into a filtrate tank 35 at the same time. The paint components are concentrated and returned to the concentration tank 33 again. The concentrated liquid which has reached the required concentration by repeating the circulation filtration as described above is added to the paint in the paint tank 6 and reused. The filtrate stored in the filtrate tank 35 is supplied as fresh cleaning water to the shower nozzle 411 by the pump P4 for final cleaning during cleaning.

In the present invention, as described above, the part having a complicated structure and difficult to clean is exchanged as an exchange unit 21 at a time, so that the cleaning at the time of color change is performed only by the washing booth 20 and the suction duct 22 which are difficult to move. . Plastic materials such as polypropylene, hard vinyl chloride or acrylic resin are used as these structural materials. If the internal shape is smoothed by welding, bonding or casting, it can be easily cleaned without causing paint stickiness or liquid pools. be able to.

As shown in FIG. 1, the washing booth 20 has an inclined bottom surface for discharging the washing water from a discharge port at the lower end, and a working scaffold is required when a cleaning worker enters the booth. . However, permanent installation of a scaffold in the booth goes against simplification of the internal shape, and thus requires temporary installation of the scaffold each time cleaning is performed. In the present invention, an electric gondola for cleaning is prepared for such a case. FIG. 4 is a diagram for explaining the relationship between the washing booth 20 and the gondola. The ceiling of the water-washing booth 20 is provided with a cutout serving as a passage for the hanger 3 suspended on the work conveyor 2 and a gondola hanger 37 suspended on a pair of rails 36 sandwiching the work conveyor 2. And electric gondola 3
8 is suspended on a pair of rails 36 and is capable of self-propelled in forward and reverse directions by a drive motor (not shown),
During the painting operation, the operator stands by outside the booth, and when the color is changed, the cleaning operator 39 is carried and the vehicle runs in the booth, thereby making the cleaning operation easy and quick.

[0017]

As described above, according to the water-based paint coating booth of the present invention, the cleaning time which must be performed at the time of color change in order to collect and use the overspray paint is greatly reduced, and the conventional color paint is used. Line stoppage, which required 1-2 hours for each replacement, can be reduced to 10-15 minutes. Further, since the collection device 25 in each exchange unit 21 can be operated offline, the capacity of the filter does not need to be matched to the consumption of the paint, and the size can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of the overall configuration of a water-based paint coating booth according to the present invention.

FIG. 2 is a block diagram illustrating the operation of the replacement unit according to the present invention.

FIG. 3 is a cross-sectional view for explaining an internal structure of a cleaning chamber.

FIG. 4 is a diagram showing the interrelationship between the flush painting booth and the electric gondola of the present invention.

FIG. 5 is a diagram showing a main configuration of a conventional water-based paint painting booth capable of collecting paint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Work 2 Conveyor 3 Hanger 4 Painting booth 411,711,712 Shower nozzle 5 Spray gun 6 Paint tank 7,22 Suction duct 8 Exhaust fan 11 Recovery tank 12,34 Ultrafiltration filter 13,35 Filtrate tank 20 Rinse booth 21 Replacement Unit 23 Cart 24 Washing room 25 Collection device 26, 27 Cylinder 28, 29 Sleeve 31 Cleaning tank 33 Concentration tank 36 Rail 37 Gondola hanger 38 Electric gondola

Claims (4)

[Claims] 1. A washing device which is detachably mounted between a washing water discharge port at the bottom of a washing booth and a suction port of a suction duct to introduce the discharged washing water and to wash mist contained in exhaust gas. Chamber, a concentration tank that collects and circulates in the washing tank at the bottom of the washing chamber and pumps up and stores a part of the washing water for washing the inside of the booth, and ultrafiltrate the liquid stored in the concentration tank. An exchange unit in which an ultrafiltration device that concentrates and returns to the concentration tank again, and a filtrate tank that stores the filtrate separated from the ultrafiltration device and supplies the filtrate as fresh washing water is mounted on a cart. A water-based paint booth characterized by being provided for each color of paint used. 2. The water-based paint application booth according to claim 1, wherein the main body of the water-wash booth is made of a plastic material such as polypropylene, hard vinyl chloride or acrylic resin and has a smooth inner surface shape. 3. An electrically operated washing booth, which is suspended on a rail provided above the booth, stands by outside the booth during a painting operation, and travels inside the washing booth with a cleaning worker on it when changing colors. The water-based paint painting booth according to claim 1, further comprising a gondola. 4. The mounting and dismounting of the exchange unit is performed by a flange connection, and a booth side flange and a duct side flange are respectively provided at a lower end of a sleeve that slides vertically along the side surfaces of the discharge port and the suction port by driving a cylinder. The waterborne paint coating booth according to claim 1, which is attached.