JP7573337B2 - Painting Equipment - Google Patents

Description

The present invention relates to a coating equipment, and more particularly to a dry coating equipment having a disposable filter module.

In painting equipment, methods for collecting paint mist that has not adhered to the workpiece can be broadly divided into wet methods, which use water, and dry methods, which do not use water. With the wet method, paint mist can be collected efficiently, but because water needs to be circulated, the equipment is large-scale, resulting in high initial investment and high running costs. On the other hand, with the dry method, because there is no need to circulate water, the equipment can be smaller than the wet method, and running costs are also reduced.

For example, in the dry painting equipment shown in Patent Document 1 below, a filter unit with a paper mist separator is placed below the painting booth where painting takes place.

Patent No. 6831499

In the above-mentioned painting equipment, a uniform vertically downward airflow is generated in the painting booth to stabilize the painting quality. This air is sucked into the exhaust port (exhaust opening 30) provided at the bottom of the painting booth. However, in the above-mentioned Patent Document 1, the workpiece arranged in the painting booth and the exhaust port (the inlet of the filter unit) at the bottom of the painting booth are offset in the horizontal direction, so there is a risk of an airflow inclined to the vertical direction (hereinafter referred to as a "diagonal flow") occurring in the painting booth, especially near the workpiece. If a diagonal flow occurs near the workpiece, it will cause variation in the painting quality (e.g., film thickness).

Therefore, the present invention aims to stabilize the painting quality by suppressing the occurrence of diagonal flow near the workpiece in dry painting equipment.

In order to solve the above problems, the present invention provides a coating equipment including a coating booth having a coating chamber and an exhaust chamber provided below the coating chamber, and a disposable filter module for removing paint mist contained in air exhausted from the exhaust chamber,
The coating equipment further comprises a filter module disposed on a side of the exhaust chamber, and an exhaust port for discharging the air from the exhaust chamber is provided on a lower part of the side surface of the exhaust chamber.

As described above, by locating the filter module on the side of the exhaust chamber rather than below it, the exhaust chamber can be extended downward to the side of the filter module. And by locating the exhaust port of the exhaust chamber at the bottom of the side of the exhaust chamber, the vertical distance between the workpiece placed in the paint booth and the exhaust port can be increased without changing the height of the paint booth. As a result, when air is sucked in from the exhaust port in the paint booth, the vertically downward air flow in the paint booth can be gently bent toward the exhaust port, thereby suppressing the occurrence of diagonal flows near the workpiece.

In the above-mentioned painting equipment, in order to suck all the air in the painting booth from the exhaust port into the filter module, it is generally considered desirable to make the air flow velocity at the exhaust port as fast as possible. However, the inventors' verification has revealed that if the flow velocity at the exhaust port is fast, a large amount of paint will adhere to the exhaust port of the exhaust chamber, reducing the amount of paint recovered by the filter module and actually worsening the paint recovery efficiency. Therefore, it is preferable to set the air speed at the exhaust port low, specifically 6 m/s or less.

As described above, the dry coating equipment of the present invention can suppress the occurrence of diagonal flows near the workpiece, stabilizing the coating quality.

1 is a cross-sectional view of a painting facility according to an embodiment of the present invention.

The following describes an embodiment of the present invention with reference to the drawings.

Figure 1 shows a painting facility that paints automobile parts (e.g., bumpers). This painting facility is a dry painting facility that collects paint mist (overspray) that does not adhere to the workpiece W without using water. This painting facility has a painting booth 1 inside which the workpiece W is painted, and a paint mist removal device 20 that removes paint mist in the air discharged from the painting booth 1.

Inside the painting booth 1, there is a painting chamber 2 where the workpiece W is painted, an air supply chamber 3 provided above the painting chamber 2, and an exhaust chamber 4 provided below the painting chamber 2. A ceiling wall 8 and a floor wall 9 having a large number of air holes are provided at the boundary between the painting chamber 2 and the air supply chamber 3, and at the boundary between the painting chamber 2 and the exhaust chamber 4. The painting booth 1 is provided with an air supply port 3a for supplying air to the air supply chamber 3 and an exhaust port 4a for exhausting air from the exhaust chamber 4. The workpiece W is supported by a work support part 10 and is placed in the painting chamber 2. In the illustrated example, the workpiece W is placed in a position offset horizontally to one side (opposite the exhaust port 4a) from the center of the painting chamber 2. A painting robot 11 that paints the workpiece W is provided in the painting chamber 2. Air supplied to the air supply chamber 3 from the air supply port 3a is supplied to the paint chamber 2 through the air vent in the ceiling wall 8, and is exhausted to the exhaust chamber 4 through the air vent in the floor wall 9. As a result, a uniform vertical downward air flow is generated in the paint chamber 2.

The paint mist removal device 20 includes a duct 5 connected to the paint booth 1, and a primary filter module 6 and a secondary filter 7 provided inside the duct 5. In this embodiment, the paint mist removal device 20 is disposed below the paint chamber 2 of the paint booth 1 and adjacent to the side of the exhaust chamber 4.

The duct 5 has a filter duct 5a extending vertically, an exhaust duct 5b extending horizontally (perpendicular to the plane of FIG. 1), and a connecting duct 5c that connects the filter duct 5a to the exhaust chamber 4. The side wall of the exhaust chamber 4 and the duct 5 are airtightly connected. In the illustrated example, the lower part of the exhaust chamber 4 and the lower part of the filter duct 5a are connected via the connecting duct 5c. The exhaust duct 5b is connected to the upper end of the filter duct 5a. In the illustrated example, a large number of paint booths 1 are arranged side by side in the direction perpendicular to the plane of FIG. 1, and the filter ducts 5a connected to each paint booth 1 are connected to a common exhaust duct 5b.

The primary filter module 6 and the secondary filter 7 are arranged inside the filter duct 5a. The primary filter module 6 is arranged upstream in the air flow direction, and the secondary filter 7 is arranged downstream of the primary filter module 6. In the illustrated example, the primary filter module 6 is arranged near the floor surface, and the secondary filter 7 is arranged on top of it. The primary filter module 6 is a so-called inertial filter that causes air to collide with a filter element (e.g., a filter plate) to cause paint mist to adhere to it. The primary filter module 6 is made of a flammable material such as paper or wood, and is made of cardboard in this embodiment. The secondary filter 7 is a so-called filtration filter that allows air to pass through a porous filter (e.g., a nonwoven fabric filter) to capture the paint mist.

The workpiece W is painted by spraying paint mist from the nozzle of the painting robot 11 onto the workpiece W. The paint mist that does not adhere to the paint is discharged together with the air into the exhaust chamber 4 below through the air vent in the floor wall 9. The air containing the paint mist is sucked into the duct 5 through the exhaust port 4a by a fan (not shown), and the paint mist in the air is removed by the primary filter module 6 and the secondary filter 7 arranged in the duct 5. In this embodiment, most of the paint mist contained in the air (e.g., 80% or more, preferably 90% or more) is removed by the primary filter module 6, and the remaining paint mist is removed by the secondary filter 7. The air from which the paint mist has been removed is discharged to the outside through the exhaust duct 5b, or is supplied again to the air supply chamber 3 of the painting booth 1. As use progresses, paint accumulates on the primary filter module 6 and the secondary filter 7. Each filter module 6, 7 is disposable, and when more than the allowable amount of paint accumulates, it is discarded together with the collected paint.

In the above-mentioned painting equipment, the exhaust chamber 4 extends downward from the painting chamber 3 to the side of the primary filter module 6, and an exhaust port 4a is provided at the bottom of the side of the exhaust chamber 4. In the illustrated example, the exhaust port 4a is provided at a height near the floor surface. This allows the vertical distance from the workpiece W arranged in the painting chamber 2 to the exhaust port 4a to be increased, and as shown by the arrow in Figure 1, the air exhausted from the painting chamber 2 can reach the exhaust port 4a while gradually changing its flow direction in the exhaust chamber 4. This makes it difficult for a diagonal flow to occur near the workpiece W, stabilizing the painting quality.

In addition, by increasing the height dimension of the exhaust chamber 4 as described above and gradually changing the air flow direction, the paint mist can be carried along by the air flow and smoothly sucked in. This reduces the amount of paint that adheres to the sides and floor of the exhaust chamber 4, making the inside of the paint booth 1 less likely to become dirty and reducing the frequency of maintenance. In addition, paint can be collected in the primary filter module 6 and secondary filter 7, which are originally used to collect paint, eliminating the need to dispose of paint.

Furthermore, in this embodiment, the air in the painting booth 1 is sucked in at a low flow rate from the exhaust port 4a while the air flow direction in the exhaust chamber 4 is gradually changed as described above. Specifically, the suction force of the fan and the size (flow path area) of the exhaust port 4a are adjusted so that the air flow rate at the exhaust port 4a is 6 m/s or less. In this way, by suppressing the flow rate at the exhaust port 4a, paint is even less likely to adhere to the vicinity of the exhaust port 4a in the painting booth 1.

Reference Signs List 1 Paint booth 2 Paint room 3 Air supply room 4 Exhaust room 4a Exhaust port 5 Duct 5a Filter duct 5b Exhaust duct 5c Connecting duct 6 Primary filter module 7 Secondary filter module 8 Ceiling wall 9 Floor wall 10 Workpiece support 11 Painting robot W Workpiece

Claims (4)

A coating equipment including a coating booth having a coating chamber and an exhaust chamber provided below the coating chamber, and a disposable filter module for removing paint mist contained in air discharged from the exhaust chamber,
The filter module is an inertial filter that causes air to collide with a filter plate to attach paint mist,
The filter module is disposed on a side of the exhaust chamber, and an exhaust port for discharging the air from the exhaust chamber is provided on a lower part of a side surface of the exhaust chamber;
The filter module is disposed so as to face the exhaust port in a horizontal direction ;
The air discharged from the exhaust port flows into the filter module from the side and is discharged from above . The coating equipment according to claim 1, wherein the wind speed at the exhaust port is 6 m/s or less. 3. The coating facility according to claim 1 , wherein the exhaust port is arranged to face only a lower portion of the filter module in the horizontal direction . The coating facility according to any one of claims 1 to 3, wherein a workpiece is disposed at a position offset from the center of the coating chamber on the opposite side to the exhaust port.

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