JPH0663463A - Powder painting booth - Google Patents

Abstract

PURPOSE:To perform color replacing work within a short time and to reduce the arrangement space of a replacing member by providing a device shaking down an over-spray powder to a replaceable recovery filter and providing the recovery device of the over-spray powder on the belt conveyor provided to the bottom part of a painting booth. CONSTITUTION:A powder painting booth is constituted so that an exhaust port is provided to a booth main body 1 having a belt conveyor 5 provided to the bottom part thereof and a suction blower 12 is connected to the exhaust port and an over-spray powder recovering filter 7 is attached to the exhaust port of the booth main body 1 in a replaceable manner and an over-spray powder shaking-down device 20 is provided above the belt conveyor 5. An over-spray powder is bonded to the surface of the filter 7 in the booth main body 1 to be collected and shaken down to the belt conveyor 5 by the shaking-down device to be recovered in a recovery device 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder coating booth in an electrostatic powder coating apparatus, and more particularly to a powder coating booth capable of performing color changing work in a short time.

[0002]

2. Description of the Related Art Conventionally, an exhaust duct has been connected to a powder coating booth in order to exhaust the interior of the booth body.

The booth body exhausted from the exhaust duct contains overspray powder, which has not adhered to the object to be coated, among the powder paint discharged from the coating gun. An exhaust dust collector is connected to the duct to separate and collect overspray powder.

[0004]

By the way, in the above powder coating booth, when the color of the powder coating to be used is changed, in order to avoid color mixing, the exhaust duct and the exhaust dust collecting are provided together with the inside of the booth main body. Equipment must be cleaned.

However, it takes a lot of time to clean the inside of the exhaust duct and the inside of the exhaust dust collector. In addition, it is difficult to completely remove the overspray powder in the exhaust duct or the exhaust dust collector even after cleaning.

For this reason, in order to completely prevent color mixing due to color change, the exhaust duct and the exhaust dust collector may be replaced for each color change. There is a problem that a large number of large-sized exhaust dust collectors for exhausting and collecting the overspray powder must be prepared, which requires a large installation space.

Therefore, the present invention is intended to provide a powder coating booth which does not require cleaning of the exhaust duct at the time of color change and can perform the color change work in a short time.

[0008]

In order to solve the above-mentioned problems, the present invention provides an exhaust port in a booth main body whose bottom part is a belt conveyor, and connects an exhaust device to the exhaust port, A filter for collecting overspray powder was replaceably attached to the exhaust port, a device for scraping off the overspray powder was installed on this filter, and a device for collecting overspray powder was installed on the belt conveyor at the bottom.

[0009]

According to the above structure, the overspray powder is
Collected by adhering to the surface of the filter installed in the booth body.

The overspray powder collected by the filter is scraped off on the belt conveyor at the bottom by the scraping device and collected by the collecting device.

As described above, according to the present invention, the overspray powder is separated and collected in the booth body.

Therefore, when the color is changed, only the inside of the booth main body needs to be cleaned, so that the cleaning time can be extremely shortened.

Further, when the color is changed, it is not necessary to replace the entire exhaust dust collector including the filter and the exhaust device as in the conventional case, and only the filter in the booth body needs to be replaced. The replacement work can be performed quickly, and the storage space for the replacement member can be kept small.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below.

The booth body 1 has entrances and exits for the article to be coated 2 at both ends, and a conveyor device 3 for moving the article to be coated is installed on the top surface so that the article 2 to be coated passes through the booth body 1. Has become.

A powder coating gun 4 is provided on the side surface of the booth body 1.
Is arranged, and the powder coating material 4 is discharged from the powder coating gun 4 toward the article 2 to be coated.

The bottom of the booth body 1 is composed of a belt conveyor 5 which moves toward the inlet side or the outlet side, and among the powder coating materials discharged from the powder coating gun 4 toward the article 2 to be coated. The overspray powder that has not adhered to the article to be coated 2 falls onto the belt conveyor 5.

It is desirable that the side surface and the top surface of the booth main body 1 be formed of a semiconductor resin to which overspray powder is unlikely to adhere.

Inside the opposite side surfaces of the booth body 1, filter units 6 for collecting overspray powder are installed at the inlet side and the outlet side in front of and behind the space through which the article to be coated 2 passes. Has been done.

As shown in FIG. 4, the filter unit 6 is formed by integrating a plurality of filters 7 each having an open upper surface with a fixed plate 8. The fixed plate 8 is provided inside the top surface of the booth body 1. Can be replaced by removably attaching it by means of a quick-moving joint 9.

The top surface of the booth body 1 and the fixing plate 8
An opening is formed at the opening corresponding to the opening of the filter 7. A backwash chamber 10 is installed above the opening on the top surface of the booth body 1.

An air outlet 11 is provided on the opposite side wall of the backwash chamber 10 installed above the front and rear filter units 6.
Are formed. Air outlet 11 of back and forth backwash chamber 10
A suction passage 13 in which a suction blower 12 is installed is connected to.

On the upper wall of the backwash chamber 10 is installed a backwash nozzle 14 for ejecting compressed air toward the opening of the filter 7 as a device for removing the overspray powder adhering to the filter 7. Compressed air is discharged for 0.1 to 0.5 seconds at predetermined intervals.

A venturi tube 1 is provided in the backwash chamber 10.
5 is installed by a cylinder 16 so as to be vertically movable. The Venturi tube 15 is located at the opening of the filter 7 when pushed downward by the cylinder 16, and is separated from the opening of the filter 7 when pulled upward by the cylinder 10 and separated from the opening of the filter 7. And the air outlet 1 of the backwash chamber 10
An air flow passage is formed between the air flow path and the air flow path 1.

An open / close damper 17 for opening / closing the suction passage 13 is installed at the air outlet 11 of the backwash chamber 10. The opening / closing damper 17 is connected to the Venturi pipe 15, and when the Venturi pipe 15 is pushed down by the cylinder 16, the suction passage 13 is closed, and when the Venturi pipe 15 is pulled upward, the suction passage 13 is opened. It moves up and down in conjunction with each other.

An atmospheric air inlet 18 is formed on the outer side wall of the backwash chamber 10 at a position closer to the upper side. An opening / closing damper 19 is installed at the air inlet 18.
The opening / closing damper 19 for inflowing to the atmosphere is also the venturi 1
5, the venturi tube 15 is pushed downward by the cylinder 16, and the atmosphere inlet 18
Open, and when pulled upward, it moves up and down in conjunction with the Venturi tube 15 so as to close the atmosphere inlet 18.

During normal operation, that is, when performing suction work with the filter 7, as with the filter 7 on the left side of FIG. 3, the venturi tube 15 is pulled upward by the cylinder 16 to open / close the suction passage 13 with the opening / closing damper 17. Open
The open / close damper 19 of the large airflow inlet 18 is closed. With this arrangement, the suction air passing from the outer surface to the inner surface of the filter 7 does not pass through the Venturi tube 15 but directly passes through the air outlet 11 and flows into the suction passage 13, so that the passage is narrow. The suction air is not obstructed by the exhausted venturi pipe 15, and the differential pressure of the filter 7 can be reduced.

During the backwashing operation, the venturi tube 15 is pushed down by the cylinder 16 like the filter 7 on the right side of FIG. 3, the opening / closing damper 17 of the suction passage 13 is closed, and the atmosphere inlet 18 is opened. Open the open / close damper 19 and then press compressed air from the backwash nozzle 14 to
Blow into the Venturi tube 15 for 0.5 seconds,
The compressed air is not weakened by the suctioned air from the suction blower 12, and the venturi tube 15 sucks the surrounding air, and a large amount of air vigorously passes through the filter 7 from the inner surface to the outer surface of the filter 7, so that the dust particles Very effective in removing fluff.

Thus, during the backwashing operation, the suction blower 1
The suction passage 13 of 2 is blocked by the opening / closing damper 17,
The compressed air ejected from the backwash nozzle 14 is prevented from being weakened by the suction air, and the venturi tube 15 is moved to a position away from the opening portion of the filter 7 during normal operation, so that the suction air is absorbed.
In the case of the above-described embodiment of the present invention in which the passage obstruction is prevented by 5, the backwash operation is performed without blocking the suction passage 13, and the normal operation is performed with the venturi tube 15 positioned at the opening of the filter 7. As compared with the case of performing the operation as it is, as shown in the graph of FIG. 5, in the case of the embodiment of the present invention, the pressure loss of the filter can be suppressed to an extremely low value.

The experimental conditions in the graph of FIG. 5 are as follows.

The suction blower ^{performance: 40m 3 / min 200mmAg 3.7KW 220V} 60HZ Filter Number: 2 filtering air volume: 20 m ³ / min (one each) = total 40 m ³ / min filtration area: 10 m ^2/1 Main = 20 m ² Filter opening diameter: 200 mm Venturi tube throat diameter: 100 mm Next, about 40-60% of the overspray powder falls directly onto the belt conveyor 5 at the bottom of the booth body 1, and the remaining 60- 40% is sucked by the filter 7 in the booth body 1 and adheres to the outer surface of the filter 7.

The overspray powder adhering to the outer surface of the filter 7 is scraped off by the above-mentioned backwashing operation and drops onto the belt conveyor 5.

The overspray powder thus collected on the belt conveyor 5 is moved to one end of the booth body 1 by the belt conveyor 5 and collected. As the recovery device 20 for collecting the overspray powder on the belt conveyor 5, a suction head 22 connected to a cyclone type dust collector 21 may be used to suck and collect the overspray powder on the belt conveyor 5, or a belt conveyor. It is also possible to collect the overspray powder on No. 5 by scraping it with a rubber wiper. In the embodiment of FIG. 1, a cyclone type dust collector 21 is used. The overspray powder collected by the collection device 20 is collected in the collection powder tank 23, and after being selected, sent to the powder coating gun 4 for reuse. In FIG. 1, reference numeral 24 indicates an exhaust device of the cyclone type dust collector 21.

Next, when changing colors, first, the filter 7 installed in the booth body 1 is removed. The removal work of the filter 7 may be performed one by one,
It is convenient to remove the fast-moving joint 9 and perform it for each filter unit 6 integrated with the fixed plate 8. When replacing the filter 7, as shown in FIG. 4, to prevent the overspray powder adhering to the filter 7 from scattering,
It is desirable to store the filter 7 in the storage case 25.

After removing the filter as described above, the inside of the booth body 1 is cleaned with a wiper or the like.

Further, the collecting device 20 for collecting the overspray powder on the belt conveyor 5 is replaced or cleaned as necessary.

After the interior of the booth body 1 has been cleaned as described above, a new filter 7 according to the powder paint to be color-changed is attached to the booth body 1 to complete the color-changing work.

[0038]

In the powder coating booth of the present invention, it is not necessary to clean the inside of the exhaust duct at the time of color change as in the conventional case, and the replacement work at the time of color change is performed in the booth body. Since only the filter is required and it is not necessary to replace the entire dust collector including the exhaust system of the booth, there is an effect that the color changing work can be performed in an extremely short time and the installation space for the replacement member may be small. .

[Brief description of drawings]

FIG. 1 is an overall front view showing an example of a powder coating booth according to the present invention.

FIG. 2 is a side view of the above.

FIG. 3 is a detailed view of a backwash device portion of the above.

FIG. 4 is a perspective view of a filter unit.

FIG. 5 is a graph showing the results of the effect confirmation experiment.

[Explanation of symbols]

 1 Booth Main Body 2 Conveyor Device 3 Conveyor Device 4 Powder Coating Gun 5 Belt Conveyor 6 Filter Unit 7 Filter 8 Fixed Plate 9 High Speed Joint 10 Backwash Room 11 Air Outlet 12 Suction Blower 13 Suction Passage 14 Backwash Nozzle 15 Venturi Pipe 16 Cylinder 17 Open / close damper 18 Large airflow inlet 19 Open / close damper 20 Collection device 21 Cyclone type dust collector 22 Suction head 23 Collected powder tank 24 Exhaust device 25 Storage case

Claims (1)

[Claims] 1. An exhaust port is provided in a booth body having a belt conveyor at the bottom, an exhaust device is connected to the exhaust port, and an overspray powder recovery filter is replaceably attached to the exhaust port in the booth body. The powder coating booth is characterized in that the collecting filter is provided with a device for removing the overspray powder, and the collecting device for the overspray powder is provided on the belt conveyor at the bottom.