JPH09314024A - Coating device for recovering type water-soluble coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and easily collect an unused coating material and recover and regenerate a coating material by supplying a swelling liquid from an upper side of a filter which collects the unused coating material so that the filter is maintained in a wet state, and recovering the swelling liquid flowing through the lower side of the filter, and separating the unused coating material to reuse. SOLUTION: In a boxlike coating booth 10, a work 14 is carried by a ceiling overhead conveyer in the perpendicular direction of the figure. During the work 14 is carried, it is coated with a coating material which is injected through an injection nozzle 16a of an injecting device 16 of the coating material. A wet filter 18 and a dry filter 20 are disposed inside of the coating booth 10 to collect the unused coating material which does not deposit on the work 14. A swelling liquid is supplied from a liquid supply part 26 and passed from the upper part and through the surface and the inside of the wet filter 18. The swelling liquid flowing out of the filter is recovered in a liquid recovering zone 28, pumped by a pump 30 and fluxed through a circulating passage 32. In this case, the filtrate obtd. by a filtering device 36 is circulated for use as a filter cleaning liquid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recovery type water-soluble paint coating apparatus, and more particularly to improvement of recovery of collected uncoated paint.

[0002]

2. Description of the Related Art Conventionally, an object to be coated (work) is continuously transferred in a coating booth by using a transfer means such as an overhead conveyor, and a paint injection device or the like is used for the transferred work. A coating device for performing coating by using a coating is widely used. At this time, the mist-like uncoated paint that does not adhere to the work inside the painting booth and floats inside the painting booth must be securely collected to prevent it from leaking outside the painting booth or reattaching to the work. It is necessary to collect and collect.

In this case, generally, a ventilation fan or the like is used to generate a constant air flow in the coating booth, and the mist-like uncoated paint is put on this air flow to pass through a plurality of air filters. Depending on the method, there is a method of collecting the above-mentioned mist-like uncoated paint, a method of causing floating uncoated paint to collide with a water curtain, and dropping it together with a used liquid of the water curtain to collect.

By the way, recently, the uncoated paint which has not been applied to the work during the spray coating is recovered, and if necessary, a reclaiming treatment such as filtration is performed, and the reclaimed paint is used for recoating. The recycling use of is proposed. In the case of this method, after applying the uncoated paint to the air filter,
After recovering the cleaning liquid containing uncoated paint obtained by cleaning the filter and the liquid used for the water curtain containing uncoated paint, etc., the collected liquid is concentrated liquid (paint) and filtrate with a UF device or the like. It is separated into and reused for painting again as recycled paint.

[0005]

However, when the above-described paint is recycled and used with an air filter, when the water-soluble paint is a normally dry paint, the water-soluble paint is hardened before cleaning or has a viscosity. There are problems such as rising and becoming unable to recycle, and clogging of the filter to reduce the collection efficiency. Therefore, it is necessary to frequently clean the air filter for collecting the paint, and there is a problem that the coating device cannot be efficiently operated.

Further, even in the case of thermosetting paint, the problem of filter clogging due to the viscosity of the paint occurs.

On the other hand, when using a water curtain,
A large amount of liquid, such as water, is required and the running cost becomes huge, and the gas containing the uncoated paint does not pass through the water curtain like the air filter, so the uncoated paint is collected. There is a problem of low efficiency.

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is a recoverable water-soluble paint capable of collecting uncoated paint and recovering and reproducing the paint efficiently and easily. It is to provide a coating device.

[0009]

In order to achieve the above object, the first invention is to spray a water-soluble paint on a conveyed work so as to coat it, and to apply an uncoated water-soluble paint. In a recovery type water-soluble paint coating device that is collected and reused for coating, a coating booth for coating the work with the water-soluble paint sprayed from a spray nozzle during passage of the work, and a coating booth provided in the coating booth A breathable filter, which is a filter for adhering and collecting uncoated paint which has not been applied to the work, and a liquid supply unit for supplying a wetting liquid from the upper part of the filter to keep the filter in a wet state at all times And a liquid recovery part for recovering the wetting liquid flowing out from the lower part of the filter, and separating the uncoated paint collected by the filter from the filter by the wetting liquid flowing out from the filter Characterized in that it use.

According to this structure, the filter is always kept in a wet state by the wetting liquid (for example, a liquid containing water as a main component) constantly supplied, and the mist-like uncoated paint passes through the air-permeable filter. When it does, it is collected by the filter. At this time, since the uncoated paint is diluted with the wetting liquid, it is possible to prevent the viscosity of the paint from increasing and hardening. Further, since the paint diluted with the wetting liquid easily flows out together with the wetting liquid from the lower part of the filter, the paint can be easily collected without leaving the paint on the filter, and the maintenance of the filter becomes unnecessary. .

In order to achieve the above object, a second aspect of the present invention is a recovery type water-soluble paint coating apparatus according to the first aspect of the invention, wherein a filtrate obtained by filtering the wetting liquid recovered by the liquid recovery section is filtered. It is characterized in that it is reused as a cleaning liquid.

According to this structure, the cleaning effect of the filter can be improved and the unpainted coating material can be collected by circulating the filtrate, which is separated from the coating material and containing less impurities, as the wetting liquid (cleaning liquid). It is possible to improve efficiency and paint collection efficiency.

In order to achieve the above-mentioned object, a third invention is the recovery type water-soluble paint coating apparatus of the first invention or the second invention, wherein the filter is formed of fine fibers. And

According to this structure, the contact area between the mist-like uncoated paint and the filter is increased, so that the collection efficiency is improved, and since the fine fibers have a water replenishing power, a large amount of wetting liquid is not required. The operating efficiency of the coating device can be improved.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a conceptual diagram of the constitution of a recovering type water-soluble paint coating apparatus of this embodiment. The box-shaped coating booth 10 has an overhead conveyor 12 on the ceiling.
The work 14, which is an object to be coated, is conveyed in a direction perpendicular to the paper surface from a work input port (not shown) toward the work discharge port. Then, the work 14 is being conveyed, and the spray nozzle 16 of the paint spraying device 16 disposed in the coating booth 10 is in operation.
Painting is performed with a predetermined paint sprayed from a.
In the case of FIG. 1, only one injection nozzle 16a is shown, but a plurality of injection nozzles 16a may be arranged. Further, the work 14 may be rotated during the transportation of the work 14 to spray the paint on the entire work 14.

Inside the coating booth 10, two types of filters, a wet filter 18 and a dry filter 20 which will be described later, are arranged to collect uncoated paint which has been sprayed from the spray nozzle 16a and has not been applied to the work 14. However, it is prevented from flowing out of the coating booth 10 through the exhaust port 22 of the coating booth 10.

The wet filter 18 is formed by, for example, a metal such as aluminum or stainless steel which is cut into a thread shape and bundled into a fibrous shape, a chemical fiber or the like, and is held by a frame 24 as shown in FIG. It is hung from the ceiling of booth 10.

The characteristic feature of this embodiment is that a wetting liquid (for example, a wet liquid) is provided on the wet filter 18 as shown in FIG.
The wet filter 18 is always maintained in a wet state by having a liquid supply unit 26 for supplying a liquid containing water as a main component.

The liquid supply unit 26 has a circulation passage 32 for circulating and supplying the wetting liquid through a pump 30 from a liquid collecting unit 28 which collects the wetting liquid flowing out of the surface and inside of the wet filter 18. A filtrate flow path 34 for supplying a filtrate filtered by a filter device described later is connected.

As described above, a constant amount of the wetting liquid is constantly supplied from the upper part of the wet filter 18 by the liquid supply unit 26 and flows down along the fibers of the wet filter 18. A plurality of openings 24a are formed in the lower portion of the frame 24, and the wet filter 1
The wetting liquid that has flowed down inside and on the surface of 8 is smoothly dropped into the liquid recovery unit 28.

Further, in the case of this embodiment, since the wet filter 18 is fibrous, the exhaust fan 2 of the exhaust port 22 is provided.
The mist-like uncoated paint passes through the wet filter 18 along with the airflow generated by the driving of 2a or the like. As a result, the uncoated paint is wet filter 1
Although it is collected when passing through the wet filter 18,
Since the wetting liquid constantly flows on the surface (fiber surface) of, the collected uncoated paint flows down together with the wetting liquid.
Further, since the uncoated paint is diluted with the wetting liquid, it is possible to delay its viscosity increase and curing. Then, the uncoated coating material is collected together with the wetting liquid in the liquid collecting section 28. The collection rate of a general fiber filter is about 90%, and the mist-like uncoated paint that has passed through the wet filter 18 is collected by the dry filter 20 arranged on the downstream side, and is mist-like from the exhaust port 22. It prevents the uncoated paint from flowing out. The dry filter 20 is preferably replaced every predetermined period.

The wetting liquid containing the uncoated paint collected in the liquid collecting section 28 is pumped up by the pump 30 as described above, and is again supplied to the liquid supplying section 26 via the circulation flow path 32.
Is supplied to the wet filter 18. Since the uncoated paint contained in the wetting liquid is sufficiently diluted, the wet filter 18 is not clogged even when the liquid supply unit 26, the wet filter 18, the liquid recovery unit 28, and the circulation channel 32 are circulated a plurality of times. It does not occur. By forming the wet filter 18 into a fibrous shape, it is possible to improve the water retention capacity of the wetting liquid, and a small amount of wetting liquid
Since it is possible to maintain the wet filter 18 in a wet state, it is possible to reduce the size of the wetting liquid circulation device and improve the operating efficiency.

In the liquid recovery section 28, a filtration device 36 independent of the circulation flow path 32 is arranged, and the filtrate flow path 34 is provided.
It is connected to the. The filtering device 36 includes a pump 38 when, for example, the wetting liquid is circulated a predetermined number of times by the circulation passage 32, the concentration of the wetting liquid becomes higher than a predetermined value, or when the coating operation is completed. The wetting liquid accumulated in the liquid recovery unit 28 is transferred to the substitution tank 40 via the above. This time,
It is desirable to transfer all of the wetting liquid so that the wetting liquid does not remain in the wet filter 18 or the circulation channel 32. Then, the wetting liquid transferred to the replacement tank 40 is sequentially fed to the pump 4
2 and the UF device 44. The filtered filtrate is discharged to the filtrate tank 46, and the concentrated liquid generated by the filtration is returned to the replacement tank 40 again. Then, the filtration by the pump 42 and the UF device 44 is repeated, and further concentration and discharge of the filtrate are performed. When the above-mentioned concentration is performed up to a predetermined value and becomes the same level as the paint, the concentrated liquid is concentrated
8 and is returned to a paint tank (not shown) of the paint spraying device 16 at a predetermined timing and reused for painting.

As described above, since the uncoated paint is diluted with the wetting liquid and can flow out together with the wetting liquid without remaining in the wet filter 18, the collected uncoated paint can be efficiently collected, Playback can be performed.

On the other hand, the filtrate discharged to the filtrate tank 46 and accumulated in a predetermined amount is supplied to the liquid supply section 26 via the filtrate flow path 34. Then, it is supplied to the wet filter 18, and the wet filter 18 is washed with the filtrate.
At this time, since the filtrate does not contain impurities such as uncoated paint, the wetting liquid containing the uncoated paint remaining on the wet filter 18 can be further diluted and washed away.
At this time, the wet filter 18 can be completely washed by circulating the filtrate a plurality of times using the circulation flow path 32, if necessary. As described above, by regularly cleaning the wet filter 18 using the filtrate, the cleaning effect of the filter can be improved, and the collection efficiency of uncoated paint and the recovery efficiency of paint can be improved. be able to.

In this embodiment, the wet filter 1 is used.
Although the example in which 8 is formed in a fibrous shape has been described, the same effect can be obtained by forming a wet filter by stacking a plurality of plate-like materials or net-like materials having a plurality of openings.

Further, in the present embodiment, an example in which the wet filter and the dry filter are used together has been described, but the same effect can be obtained even if only a plurality of wet filters are used.

[0028]

As described above, according to the present invention,
The filter is always kept in a wet state by the wetting liquid constantly supplied, and the atomized uncoated paint is collected by the filter as it passes through the filter, and the uncoated paint is diluted by the wetting liquid. Therefore, it is possible to prevent the viscosity of the coating material from increasing and hardening. In addition, since the paint diluted with the wetting liquid easily flows out together with the wetting liquid from the lower part of the filter, unpainted paint does not remain on the filter, and the paint can be easily collected and regenerated and the filter No maintenance required.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of the configuration of a recovery-type water-soluble paint coating apparatus according to an embodiment of the present invention.

FIG. 2 is a cross-sectional explanatory view of a wet filter portion of the recovery-type water-soluble paint coating apparatus according to the embodiment of the present invention.

[Explanation of symbols]

10 Painting booth, 12 Overhead conveyor, 14
Workpiece, 16 paint injection device, 18 wet filter, 20 dry filter, 26 liquid supply part, 28 liquid recovery part, 30, 38, 42 pump, 32 circulation flow path,
34 filtrate flow path, 36 filtration device, 40 replacement tank,
44 UF device, 46 filtrate tank, 48 concentration tank.

Claims (3)

[Claims] 1. A recovery-type water-soluble paint coating apparatus for spraying a water-soluble paint onto a conveyed work for coating and collecting uncoated water-soluble paint for reuse in coating. A coating booth for coating the work with a water-soluble paint sprayed from a spray nozzle during passage of the work, and a breathable filter provided in the coating booth, which is not coated on the work. A filter for adhering and collecting the coating material, a liquid supply part for supplying a wetting liquid from the upper part of the filter to keep the filter in a wet state at all times, and a liquid collecting part for collecting the wetting liquid flowing out from the lower part of the filter. A recovering type water-soluble paint coating device, characterized in that the wet liquid flowing out from the filter separates the uncoated paint collected by the filter from the filter and reuses it. 2. The recovery type water-soluble paint coating apparatus according to claim 1, wherein a filtrate obtained by filtering the wetting liquid recovered by the liquid recovery unit is circulated and used as a filter cleaning liquid. Water-soluble paint coating equipment. 3. The recovery-type water-soluble paint coating apparatus according to claim 1 or 2, wherein the filter is formed of fine fibers.