Dry painting facility

Abstract

The present invention provides a dry painting facility in which the height of an entire painting booth can be reduced and the cleaning frequency of a booth underfloor space can be reduced. A painting booth 11 of a dry painting facility according to the present invention has a painting space that is formed on the upper side of an air-permeable floor. A painting target in the painting space is painted while being conveyed along a conveyance path 15 that extends in the longitudinal direction of the booth. Partition plates 24 that partition the internal area of the painting booth 11 into an upper area and a lower area are provided below the air-permeable floor. A booth underfloor space that is connected to a paint mist removal device as a flow path is defined in the lower area under the partition plates 24. Openings 31, 32 through which booth air flows in the booth underfloor space are formed in the partition plates 24 such that the conveyance path 15 is sandwiched therebetween. The openings 31, 32 each have a longitudinal dimension which is long in the longitudinal direction of the booth and a lateral dimension which is short in the width direction of the booth.

Description

Dry coating equipment

[0001] The present invention relates to a dry painting system comprising a painting booth for painting an object to be painted, and a paint mist removal device for removing paint mist from the booth air.

[0002] Conventionally, dry painting equipment for painting objects such as automobile bodies is known. For example, in the dry painting equipment 101 shown in Figure 18, a paint mist removal device 105 is installed in the booth floor space 104 formed directly below the painting space 103 of the painting booth 102 (see, for example, Patent Document 1). The paint mist removal device 105 has a filter housing 107 capable of housing a filter 106, and is designed to remove paint mist from the booth air A1 discharged from the painting space 103. The filter 106 takes in booth air A1 from above (painting space 103 side) and discharges it from the side (right side in Figure 18).

[0003] In addition, low-floor wet painting equipment (painting equipment in which a paint mist removal device is placed outside the side wall of the painting booth) is also known. The painting booth equipped in this painting equipment has a partition plate that divides the interior area of ​​the painting booth into a painting space and a space under the booth floor. As a result, the booth air in the painting space flows into the space under the booth floor through an opening in the partition plate, and the paint mist in the booth air adheres to the bottom surface of the space under the booth floor. The paint mist is then removed by bringing the adhered paint mist into contact with water.

[0004] Patent No. 6895011

[0005] By the way, in a dry painting facility 101 in which a paint mist removal device 105 is installed in the space under the booth floor 104, the worker must enter the space under the booth floor 104 to perform maintenance on the paint mist removal device 105 (such as filter replacement and masking). In this case, the space under the booth floor 104 needs to be raised to facilitate worker access, which raises the overall height of the painting booth 102 and creates a problem of constraints on the installation location.

[0006] Furthermore, in low-floor wet painting equipment, the airflow velocity of the booth air passing through the opening is increased to improve the straightness of the booth air. As a result, the booth air is struck against the bottom surface of the space under the booth floor, causing more paint mist to adhere to the bottom surface. In this case, the paint mist can be efficiently removed by bringing it into contact with water. However, when using low-floor dry painting equipment that does not use water, water does not flow into the space under the booth floor, so the paint mist that adheres to the bottom surface of the space under the booth floor continues to accumulate without being washed away. As a result, there is a problem of increased frequency of cleaning of the space under the booth floor.

[0007] The present invention has been made in view of the above problems, and its purpose is to provide a dry painting system that can reduce the overall height of the painting booth and reduce the frequency of cleaning the space under the booth floor.

[0008] To solve the above problems, the invention described in Means 1 is a dry painting equipment comprising: a painting booth having a pair of side walls and a breathable floor, a painting space formed above the breathable floor, and painting while transporting the object to be painted in the painting space along a transport path extending in the longitudinal direction of the booth; and a paint mist removal device having a filter housing capable of housing a filter, which removes paint mist from the booth air by flowing booth air discharged from the painting space through the filter, wherein the paint mist removal device is installed at a position offset in the width direction of the booth and outside one of the pair of side walls, and the breathable floor The gist of this dry painting equipment is that a partition plate is provided at a lower position to divide the internal area of ​​the painting booth vertically, and in the area below the partition plate, there is an underfloor space of the booth that is flow-directly connected to the paint mist removal device, and openings are formed on both sides of the transport path of the partition plate to allow the booth air to flow into the underfloor space of the booth, and the openings have a vertical dimension that is long in the longitudinal direction of the booth and a horizontal dimension that is short in the width direction of the booth, and the underfloor space of the booth guides the booth air that has passed through the openings in the width direction of the booth and supplies it to the paint mist removal device.

[0009] According to the invention described in Means 1, the paint mist removal device is installed in a position offset in the width direction of the booth, so as to be outside one of the pair of side walls of the paint booth. This allows the height of the space under the booth floor to be lowered by the height of the paint mist removal device, and consequently, the overall height of the paint booth can be reduced. Therefore, when workers replace or protect the filters housed in the filter housing of the paint mist removal device, they do not need to enter the space under the booth floor. This makes it easy to replace and protect the filters.

[0010] Furthermore, the opening that allows booth air to flow into the space beneath the booth floor is rectangular in shape, with a long vertical dimension in the length direction of the booth and a short horizontal dimension in the width direction of the booth. As a result, the booth air passing through the opening becomes thinner in the width direction of the booth, causing the air velocity to decrease and thus reducing the straightness of the booth air. Consequently, the booth air becomes more bendable, reducing the amount of paint mist that adheres to the bottom surface of the space beneath the booth floor. Therefore, the frequency of cleaning the space beneath the booth floor can be reduced.

[0011] Furthermore, openings are formed on both sides of the transport path. As a result, the booth air passing through one opening is supplied to the paint mist removal device without being obstructed by the booth air passing through the other opening, and without being disturbed by the flow of booth air passing through the other opening. Consequently, it is possible to prevent paint mist from being blown up or scattered within the space under the booth floor.

[0012] The invention described in means 2 is characterized in that, in means 1, the aspect ratio of the opening is 2.0 or more and less than 5.0.

[0013] The invention described in means 3 is characterized in that, in means 2, the wind speed of the booth air passing through the opening is 0.5 m / s or more and 3.0 m / s or less.

[0014] The invention described in means 4 is characterized in that, in means 3, the opening is a first opening located far from the paint mist removal device and a second opening located close to the paint mist removal device, and the first opening and the second opening are spaced at least 1500 mm apart. The invention described in means 5 is characterized in that, in any one of means 1 to 4, the opening is a first opening located far from the paint mist removal device and a second opening located close to the paint mist removal device, and the booth air that has passed through the first opening and the booth air that has passed through the second opening become a first airflow and a second airflow, respectively, with a reduced thickness in the booth width direction, and the first airflow is supplied to the paint mist removal device by riding on the flow of the second airflow without being obstructed by the second airflow. The invention described in means 6 is characterized in that, in any one of means 1 to 4, the transport path is constructed by installing a conveyor on a grid-shaped conveyor frame provided at a lower position than the breathable floor section, the partition plate is supported by the conveyor frame, the opening has an opening area smaller than the area of ​​one grid of the conveyor frame, and is positioned so as to avoid the position of the conveyor frame by being horizontally offset.

[0015] As detailed above, according to the inventions described in means 1 to 6, the overall height of the paint booth can be reduced, and the frequency of cleaning the space under the booth floor can be reduced.

[0016] A schematic cross-sectional view showing the dry painting equipment in this embodiment. A schematic plan view showing the paint mist removal device, the space under the booth floor, and the opening. A schematic plan view showing the conveyor frame and partition plate. A plan view of the main parts showing the conveyor frame and partition plate. A schematic perspective view showing the structure of the space under the booth floor. A table showing the relationship between the shape of the opening and the paint mist adhering to the space under the booth floor. A figure showing the wind speed distribution of booth air in Comparative Example 3. A figure showing the wind speed distribution of booth air in Example 2. A table showing the relationship between the aspect ratio of the opening and the paint mist adhering to the space under the booth floor. In Example 1A, (a) is a figure showing the wind speed distribution of booth air, and (b) is a figure showing the behavior of paint mist. In Example 2A, (a) is a figure showing the wind speed distribution of booth air, and (b) is a figure showing the behavior of paint mist. In Example 3A, (a) is a figure showing the wind speed distribution of booth air, and (b) is a figure showing the behavior of paint mist. In Example 4A, (a) is a diagram showing the air velocity distribution of the booth air, and (b) is a diagram showing the behavior of the paint mist. In Example 5A, (a) is a diagram showing the air velocity distribution of the booth air, and (b) is a diagram showing the behavior of the paint mist. A table showing Examples 1B to 4B when the processing air volume is changed. A schematic plan view showing the paint mist removal device, the space under the booth floor, and the opening in another embodiment. A schematic plan view showing the paint mist removal device, the space under the booth floor, and the opening in another embodiment. A schematic cross-sectional view showing a conventional dry painting equipment.

[0017] Hereinafter, one embodiment embodying the present invention will be described in detail with reference to the drawings.

[0018] As shown in Figure 1, the dry painting equipment 10 of this embodiment includes a painting booth 11 and a paint mist removal device 40. The painting booth 11 has a pair of side walls 12 and 13 and a breathable floor section 14 such as a grating. The side walls 12 and 13 are a first side wall 12 located farther from the paint mist removal device 40 and a second side wall 13 located closer to the paint mist removal device 40. A painting space S1 is formed above the breathable floor section 14. On the other hand, a grid-shaped conveyor frame 21 (see Figures 3 and 4) is provided at a position lower than the breathable floor section 14.

[0019] Furthermore, the painting space S1 houses a transport path 15 extending in the longitudinal direction of the booth (in Figure 1, the direction perpendicular to the plane of the paper) and a plurality of painting robots 16 positioned on both sides of the transport path 15. The transport path 15 is constructed by installing a conveyor 22 on a conveyor frame 21. In the painting booth 11, atomized paint (paint mist M1 shown in Figure 5) is sprayed onto the object to be painted W1 (a car body in this embodiment) in the painting space S1 from the paint gun of the painting robot 16, so that the object to be painted W1 is transported along the transport path 15 and painted.

[0020] As shown in Figure 1, a ceiling wall 17 is provided above the painting space S1. The ceiling wall 17 has a mesh structure, and booth air B0 is supplied to the upper side. As a result, the booth air B0 flows down through the painting booth 11 after passing through the ceiling wall 17, so that the paint mist M1 that does not adhere to the object to be painted W1 is guided downwards.

[0021] As shown in Figures 3 and 4, the conveyor frame 21 has a plurality of grids 23. Each grid 23 is rectangular in shape, with a long vertical dimension in the longitudinal direction of the booth (up and down in Figures 2 to 4) and a short horizontal dimension in the width direction of the booth (left and right in Figures 1 to 4). The aspect ratio of the grids 23 is, for example, 2.0 or more and less than 4.0. Each grid 23 is closed off by a partition plate 24 that is rectangular in shape when viewed from above. These partition plates 24 are supported by the conveyor frame 21 and divide the internal area of ​​the paint booth 11 vertically. Below each partition plate 24 is an under-booth space S2 (see Figures 1, 2, and 5) which is connected to the paint mist removal device 40 in a flow path.

[0022] As shown in Figures 1 to 4, some of the partition plates 24 have openings 31 and 32 formed in them to allow booth air B0 to flow into the space S2 under the booth floor. The openings 31 and 32 are rectangular in shape, with a vertical dimension L1 (see Figure 4) that is long in the longitudinal direction of the booth and a horizontal dimension L2 (see Figure 4) that is short in the width direction of the booth. The aspect ratio of the openings 31 and 32 is 2.0 or more and less than 5.0, preferably 2.0 or more and less than 4.0. Furthermore, the opening area of ​​the openings 31 and 32 is smaller than the area of ​​one of the grids 23 of the conveyor frame 21. Specifically, the vertical dimension L1 of the openings 31 and 32 is smaller than the vertical dimension L1' (see Figure 4) of the grid 23, and the horizontal dimension L2 of the openings 31 and 32 is smaller than the horizontal dimension L2' (see Figure 4) of the grid 23. Therefore, the opening area of ​​openings 31 and 32 is smaller than the area of ​​the grid 23.

[0023] Furthermore, multiple openings 31 and 32 are arranged adjacent to each other along the longitudinal direction of the booth, on both sides of the transport path 15 (on the left and right sides of the transport path 15 in Figures 1 to 3). Each of the openings 31 and 32 is formed within the range of one booth underfloor space S2 (see Figure 2). The openings 31 and 32 are a first opening 31 located farther from the paint mist removal device 40 and a second opening 32 located closer to the paint mist removal device 40. The first opening 31 and the second opening 32 are arranged so that their distances from the transport path 15 are equal. Specifically, the distance D1 from the center C0 of the transport path 15 (see Figure 1) to the center C1 of the first opening 31 (see Figures 1 and 3), and the distance D2 from the center C0 of the transport path 15 to the center C2 of the second opening 32 (see Figures 1 to 4) are equal to each other. Furthermore, the center C1 of the first opening 31 and the center C2 of the second opening 32 are spaced 1500 mm or more, preferably 3000 mm or more and 4500 mm or less, in the booth width direction. In addition, the pitch between the centers C1 of adjacent first openings 31 in the booth longitudinal direction is 1000 mm or more and 2000 mm or less (1500 mm in this embodiment). Similarly, the pitch between the centers C2 of adjacent second openings 32 in the booth longitudinal direction is also 1000 mm or more and 2000 mm or less (1500 mm in this embodiment).

[0024] Furthermore, as shown in Figures 3 and 4, each partition plate 24 is arranged in four rows on both the left and right sides of the transport path 15 along the width direction of the booth. The first opening 31 is formed in all of the partition plates 24 in the second row from the left among the partition plates 24 on the right side of the transport path 15. On the other hand, the second opening 32 is formed in all of the partition plates 24 in the second row from the right among the partition plates 24 on the left side of the transport path 15. In other words, the openings 31 and 32 are arranged so as to avoid the position of the conveyor frame 21 in the horizontal direction.

[0025] As shown in Figures 1, 2, and 5, the booth floor space S2 is connected to a paint mist removal device 40 via a connecting duct 25 at its end (right end in Figures 1 and 2). The booth floor space S2 is designed to guide the booth air B0 that has passed through the openings 31 and 32 in the booth width direction and supply it to the paint mist removal device 40. In this embodiment, multiple paint mist removal devices 40 are connected to the booth floor space S2. Each paint mist removal device 40 is provided only at the right end of the booth floor space S2. As shown in Figure 5, the booth floor space S2 consists of a main space S3 and a sub-space S4. Figure 5 is a diagram used for analysis, and for convenience, only a portion of the booth floor space S2, region P1 (see Figure 2), is shown. In region P1, one paint mist removal device 40 and a pair of openings 31 and 32 are arranged along the booth width direction. The height U2 of the booth floor space S2 is between 800 mm and 1500 mm, and the length U3 of the booth floor space S2 is between 4000 mm and 8000 mm. The sub-space S4 has a rectangular cross-section and extends laterally (towards the upper left in Figure 5) toward the paint mist removal device 40. The height of the sub-space S4 is smaller than the height U2 of the main space S3. Furthermore, the length U4 of the sub-space S4 is smaller than the length U5 of the main space S3, specifically between one-tenth and one-fifth of the length U5.

[0026] As shown in Figures 1 and 2, the paint mist removal device 40 is a device that removes paint mist M1 contained in the booth air B0 discharged from the paint booth 11. The paint mist removal device 40 is offset in the booth width direction (to the right in Figures 1 and 2) and is installed outside the second side wall 13, which is one of the pair of side walls 12 and 13. In other words, in this embodiment, multiple paint mist removal devices 40 are arranged on the same side of the paint booth 11.

[0027] Furthermore, the paint mist removal device 40 has a filter housing 42 capable of housing a filter 41. The paint mist removal device 40 is a device that removes paint mist M1 from booth air B0 discharged from the painting space S1 by flowing booth air B0 discharged from the painting space S1 through the filter 41 housed in the filter housing 42. An exhaust duct 51 that discharges the booth air B0 that has passed through the filter 41 is connected to the filter housing 42.

[0028] Next, we will explain how to remove the paint mist M1 contained in the booth air B0.

[0029] First, when the painting robot 16 sprays paint from its paint gun to paint the object to be painted W1, the oversprayed paint mist M1, along with the booth air B0 of the painting space S1, passes sequentially through the openings 31 and 32 of the ventilated floor section 14 and partition plate 24, and is guided to the main space S3 side of the booth floor space S2. The booth air B0 that passes through the first opening 31 becomes the first airflow B1, and the booth air B0 that passes through the second opening 32 becomes the second airflow B2.

[0030] Furthermore, the inventors of this application have newly discovered that if the openings 31 and 32 are rectangular in shape, the thickness of the airflows B1 and B2 passing through the openings 31 and 32 becomes thinner in the booth width direction. As a result, the airflow velocity of B1 and B2 decreases sharply after traveling a predetermined distance from the openings 31 and 32, reducing their straight-line directionality and making it easier to guide the airflows B1 and B2 towards the paint mist removal device 40. Moreover, the openings 31 and 32 in this embodiment are made by lengthening the vertical dimension of a conventionally used square opening (the horizontal dimension remains the same), so their cross-sectional area is larger than that of conventional openings. This also reduces the airflow velocity of the airflows B1 and B2 passing through the openings 31 and 32, reducing their straight-line directionality and making it easier to guide the airflows B1 and B2 towards the paint mist removal device 40. In addition, the inside of the filter housing 42 and the exhaust duct 51 located downstream of the booth floor space S2 are under negative pressure due to a blower (not shown). As a result, the airflows B1 and B2 introduced into the main space S3 are reliably bent from below to the side (specifically towards the paint mist removal device 40). At this time, some of the airflows B1 and B2 that were not bent collide with the bottom surface of the main space S3, causing some of the paint mist M1 contained in the airflows B1 and B2 to adhere to the bottom surface (see Figure 5).

[0031] The airflows B1 and B2, whose direction has been changed, are then supplied to the paint mist removal device 40. At this time, the second airflow B2 passes straight through the connecting duct 25 and through the filter 41 of the filter housing 42 (paint mist removal device 40). Meanwhile, the first airflow B1 is pulled and drawn in by the second airflow B2, and passes through the connecting duct 25 along with the flow of the second airflow B2, and through the filter 41 of the filter housing 42 (paint mist removal device 40). Therefore, the first airflow B1 is not obstructed by the second airflow B2. In other words, both the first airflow B1 and the second airflow B2 flow smoothly toward the paint mist removal device 40. The paint mist M1 contained in the airflows B1 and B2 is removed by adhering to the surface of the filter 41.

[0032] The airflows B1 and B2, from which the paint mist M1 has been removed, are then discharged to the outside of the filter housing 42. Subsequently, the airflows B1 and B2 are discharged to the outside of the dry painting equipment 10 through the exhaust duct 51.

[0033] Next, we will explain the comparative tests of dry-coating equipment and their results.

[0034] (1) First comparative test First, a dry coating equipment with a booth floor space of 2000 mm width, 1100 mm height, and 5800 mm length was assumed. Next, the following measurement samples were prepared by changing the dimensions of the opening in the partition plate of the dry coating equipment. Specifically, the partition plate was made with a vertical and horizontal dimension of 500 mm, an aspect ratio of 1.0, and an opening area of ​​0.25 m ２ A partition plate having a square-shaped opening (i.e., a conventional opening) was used, and this was designated as Comparative Example 1. Similarly, a partition plate with a vertical and horizontal dimension of 707 mm, an aspect ratio of 1.0, and an opening area of ​​0.5 m² was used. ２ A partition plate having a square-shaped opening was used, and this was designated as Comparative Example 2. Furthermore, the partition plate had a vertical dimension of 1000 mm, a horizontal dimension of 500 mm, an aspect ratio of 2.0, and an opening area of ​​0.5 m². ２ A partition plate having a rectangular opening was used, and this was designated as Example 1. Furthermore, the partition plate had a vertical and horizontal dimension of 866 mm, an aspect ratio of 1.0, and an opening area of ​​0.75 m². ２ A partition plate having a square-shaped opening was used, and this was designated as Comparative Example 3. Furthermore, the partition plate had a vertical dimension of 1500 mm, a horizontal dimension of 500 mm, an aspect ratio of 3.0, and an opening area of ​​0.75 m². ２ A partition plate having a rectangular opening was used, and this was designated as Example 2.

[0035] Next, for each measurement sample (Examples 1 and 2, Comparative Examples 1 to 3), a simulation was performed in which booth air from the painting space was introduced into the space under the booth floor through two openings. The total volume of booth air flowing through the openings into the space under the booth floor was set to 80 m³. ３ Assuming / min x 2, the airflow rate of booth air flowing from the space under the booth floor to the paint mist removal device is 160 m³. ３ The value was set to / min. Then, simulations were performed to calculate the proportion of paint mist contained in the booth air that adheres to the space under the booth floor and the proportion of paint mist that flows into the paint mist removal device. The results are shown in Figure 6.

[0036] As a result, in Comparative Examples 1 to 3 having a square-shaped opening, it was confirmed that the ratio of paint mist adhering to the booth floor space was 50% or more (92.4%, 72.8%, 57.5%). For example, in Comparative Example 3 (see Fig. 7), the straightness of the booth air passing through the opening is high. As a result, the booth air is slapped against the bottom surface of the main space in the booth floor space, so it is considered that a lot of paint mist adheres to the bottom surface. Also, because of the high straightness, it becomes difficult for the booth air to bend, so there are many stagnations which are the booth air retention parts, and it is considered that the paint mist adhering to the booth floor space increases. In Fig. 7, the higher the air velocity region of the booth air, the lighter the color, and the lower the air velocity region of the booth air, the darker the color. The same applies to Fig. 8.

[0037] On the other hand, in Examples 1 and 2 having a rectangular-shaped opening, it was confirmed that the ratio of paint mist adhering to the booth floor space decreased compared to Comparative Examples 1 to 3 (47.9%, 15.4%). For example, in Example 2 (see Fig. 8), compared with Comparative Example 3, the straightness of the booth air passing through the opening is relaxed. As a result, since the booth air is more likely to bend, it becomes difficult for the booth air to be slapped against the bottom surface of the main space, so it is considered that the paint mist adhering to the bottom surface decreases. Also, because the straightness is relaxed, the booth air is more likely to bend, so the stagnation decreases, and it is considered that the paint mist adhering to the booth floor space decreases.

[0038] From the above, if the opening is rectangular and long in the longitudinal direction of the booth, the straightness of the booth air passing through the opening decreases and it becomes easier to bend. As a result, the booth air flowing into the booth floor space is more likely to be pulled by the horizontal flow (the flow toward the paint mist removing device). As a result, it is considered that the ratio of the paint mist in the booth air adhering to the booth floor space decreases.

[0039] (2) Second Comparative Test Also, measurement samples were prepared as follows. A partition plate provided in the dry painting equipment was a partition plate having an opening with a vertical dimension of 1400 mm, a horizontal dimension of 500 mm, and an aspect ratio of 2.8, and this was designated as Example 1A. The partition plate was a partition plate having an opening with a vertical dimension of 1400 mm, a horizontal dimension of 450 mm, and an aspect ratio of 3.1, and this was designated as Example 2A. The partition plate was a partition plate having an opening with a vertical dimension of 1400 mm, a horizontal dimension of 400 mm, and an aspect ratio of 3.5, and this was designated as Example 3A. The partition plate was a partition plate having an opening with a vertical dimension of 1400 mm, a horizontal dimension of 350 mm, and an aspect ratio of 4.0, and this was designated as Example 4A. The partition plate was a partition plate having an opening with a vertical dimension of 1400 mm, a horizontal dimension of 300 mm, and an aspect ratio of 4.7, and this was designated as Example 5A.

[0040] Next, in each measurement sample (Examples 1A to 5A), a simulation was performed to allow booth air in the painting space to flow into the under-booth space through the opening. And a simulation was performed to calculate the wind speed of the booth air passing through the opening. Also, a simulation was performed to calculate the ratio of the paint mist adhering to the under-booth space among the paint mist contained in the booth air. The above results are shown in FIG. 9.

[0041] As a result, it was confirmed that as the aspect ratio of the opening increased, the ratio of the paint mist adhering to the under-booth space decreased. In FIGS. 10(b), FIG. 11(b), FIG. 12(b), FIG. 13(b), and FIG. 14(b), the paint mist is indicated by dots. That is, by increasing the aspect ratio of the opening, the thickness of the booth air flowing into the under-booth space becomes thinner (see FIGS. 10(a), FIG. 11(a), FIG. 12(a), FIG. 13(a), and FIG. 14(a)). Thereby, since the booth air is likely to bend toward the paint mist removing device side, the stagnation, which is the stagnant portion of the booth air, decreases, and it is considered that the paint mist adhering to the under-booth space decreases. The stagnation occurs directly below the first opening located far from the paint mist removing device and near the connection portion between the bottom and the side wall of the main space.

[0042] However, as the aspect ratio of the opening increases, the wind speed of the booth air passing through the opening increases. As a result, in Examples 4A and 5A, the booth air (second air flow) passing through the second opening located near the paint mist removal device forms an air wall in the booth underfloor space. In this case, since the booth air (first air flow) passing through the first opening is blocked by the second air flow, it was confirmed that the paint mist in the first air flow rises and scatters (see FIGS. 13(b) and 14(b)). Therefore, it was confirmed that if the aspect ratio of the opening is, for example, 2.0 or more and less than 4.0, it is possible to increase the rectification in the booth underfloor space while reducing the paint mist adhering to the booth underfloor space. Also, in Example 5A, since the wind speed of the booth air passing through the opening exceeds 3.0 m / s, it was confirmed that the flow of the paint mist is disturbed and easily meanders, and the paint mist easily adheres to the booth underfloor space. In FIGS. 10(a), 11(a), 12(a), 13(a), and 14(a), the higher the wind speed region of the booth air, the lighter the color, and the lower the wind speed region of the booth air, the darker the color.

[0043] (3) Third Comparative Test Further, when the aspect ratio of the opening is 2.0 or more and less than 4.0, and the wind speed of the booth air passing through the opening is 0.5 m / s or more and 3.0 m / s or less, measurement samples when changing the processing air volume were prepared as follows. The partition plate provided in the dry painting equipment was a partition plate having an opening with a vertical dimension of 1400 mm, a horizontal dimension of 400 mm, and an aspect ratio of 3.5, and the measurement sample with the wind speed of the booth air passing through the opening being 2.0 m / s and the processing air volume being 135 m ３ / min was used as Example 1B. The partition plate was a partition plate having an opening with a vertical dimension of 1400 mm, a horizontal dimension of 450 mm, and an aspect ratio of 3.1, and the measurement sample with the wind speed of the booth air passing through the opening being 2.1 m / s and the processing air volume being 160 m ３ / min was used as Example 2B. Also, the partition plate was a partition plate having an opening with a vertical dimension of 1400 mm and a horizontal dimension of 500 mm and an aspect ratio of 2.8. Then, the wind speed of the booth air passing through the opening was 2.3 m / s, and the processing air volume was 190 m ３Example 3B uses a measurement sample with a value of / min, and the airflow velocity of the booth air passing through the opening is 2.6 m / s, with a processing volume of 220 m³. ３ A measurement sample with a value of / min was designated as Example 4B.

[0044] Next, in each of the Examples 1B to 4B, simulations were performed to calculate the proportion of paint mist contained in the booth air that adheres to the space beneath the booth floor. The results are shown in Figure 15.

[0045] As a result, the processing airflow rate was changed to, for example, 50 m³. ３ / min or more 250m ３ Less than or equal to / min, preferably 135m ３ / min or more 220m ３ It was confirmed that setting the value to / min or less allows the percentage of paint mist adhering to the space under the booth floor to be kept low, for example, between 15% and 19%.

[0046] Therefore, according to this embodiment, the following effects can be obtained.

[0047] (1) In the dry painting equipment 10 of this embodiment, the paint mist removal device 40 is installed in a position offset in the width direction of the booth and outside the second side wall 13 of the painting booth 11. As a result, the height U2 of the space under the booth floor S2 can be lowered by the height of the paint mist removal device 40, and consequently the overall height of the painting booth 11 can be reduced. Therefore, when workers replace or mask the filter 41 housed in the filter housing 42 of the paint mist removal device 40, they do not need to enter the space under the booth floor S2. This makes it easy to replace or mask the filter 41.

[0048] Furthermore, the openings 31 and 32 that allow booth air B0 to flow into the booth underfloor space S2 are rectangular in shape, with a vertical dimension L1 that is long in the longitudinal direction of the booth and a horizontal dimension L2 that is short in the width direction of the booth. As a result, the booth air B0 that has passed through the openings 31 and 32 becomes thinner in the width direction of the booth, causing the air velocity to decrease, thus reducing the straightness of the booth air B0 (see Figure 5). In addition, the filter housing 42 of the paint mist removal device 40 located downstream of the booth underfloor space S2 is under negative pressure due to a blower (not shown). As a result, the booth air B0 is more likely to bend towards the paint mist removal device 40. Therefore, the paint mist M1 contained in the booth air B0 can be collected by concentrating it in the filter 41 in the filter housing 42, and consequently, the amount of paint mist M1 adhering to the bottom surface of the booth underfloor space S2 decreases. Consequently, the frequency of cleaning the booth underfloor space S2 can be reduced.

[0049] Furthermore, openings 31 and 32 are formed on both sides of the transport path 15. As a result, the first airflow B1, which is booth air B0 that has passed through the first opening 31, is supplied to the paint mist removal device 40 without being obstructed by the second airflow B2, which is booth air B0 that has passed through the second opening 32, and is carried along by the flow of the second airflow B2 without being disturbed. Consequently, it is possible to prevent paint mist M1 from being stirred up or scattered within the space S2 under the booth floor.

[0050] (2) As described above, in this embodiment, the height U2 of the booth floor space S2 can be lowered by the height of the paint mist removal device 40. However, when the booth floor space S2 is lowered, the booth air B0 that has passed through the opening is more likely to collide with the bottom surface of the booth floor space S2 at a high speed. As a result, there is a problem that the paint mist M1 contained in the booth air B0 is more likely to adhere to the bottom surface of the booth floor space S2.

[0051] Therefore, in this embodiment, the booth air B0 in the painting space S1 is allowed to flow into the booth underfloor space S2 through two openings 31 and 32. As a result, the flow velocity of the booth air B0 passing through the first opening 31 and the flow velocity of the booth air B0 passing through the second opening 32 are both reduced, and the collision velocity of the booth air B0 with the bottom surface of the booth underfloor space S2 is also reduced. Consequently, the adhesion of paint mist M1 to the bottom surface of the booth underfloor space S2 can be reduced.

[0052] (3) In this embodiment, the center C1 of the first opening 31 (see Figures 1 to 3) and the center C2 of the second opening 32 (see Figures 1 to 4) are spaced apart by 1500 mm or more, preferably 3000 mm or more and 4500 mm or less. As a result, the distance between the openings 31 and 32 is appropriately maintained, so that the first airflow B1 flowing in from the first opening 31 and the second airflow B2 flowing in from the second opening 32 do not interfere with each other in the space S2 under the booth floor. Therefore, it becomes possible to form airflows B1 and B2 that can smoothly guide the paint mist M1 to the paint mist removal device 40.

[0053] (4) In this embodiment, each of the multiple grids 23 of the conveyor frame 21 is closed by a partition plate 24, and openings 31 and 32 are formed in parts of the multiple partition plates 24. The opening area of ​​the openings 31 and 32 is smaller than the area of ​​one of the grids 23. This prevents the airflows B1 and B2 passing through the openings 31 and 32 from colliding with the grids 23 and being disturbed. It also prevents the paint mist M1 contained in the airflows B1 and B2 from adhering to the grids 23 and causing contamination.

[0054] (5) In this embodiment, the first opening 31 is positioned at a distance from the first side wall 12 of the paint booth 11. This prevents the first airflow B1 flowing in from the first opening 31 from colliding with the first side wall 12 and becoming turbulent. Therefore, it is possible to prevent paint mist M1 from being stirred up or scattered in the space S2 under the booth floor due to turbulence of the first airflow B1.

[0055] The above embodiment may be modified as follows.

[0056] The openings 31 and 32 in the above embodiment were rectangular in shape, having a vertical dimension L1 that is long in the longitudinal direction of the booth and a horizontal dimension L2 that is short in the width direction of the booth. However, as long as the opening has a vertical dimension that is long in the longitudinal direction of the booth and a horizontal dimension that is short in the width direction of the booth, the opening may have other shapes such as an ellipse or a rhombus.

[0057] In the above embodiment, the aspect ratio of each opening 31, 32 was 2.0 or more and less than 4.0. However, the aspect ratio of each opening 31, 32 may be 4.0 or more. For example, as shown in Figure 16, each opening 31, 32 may be an opening with a vertical dimension of 2900 mm, a horizontal dimension of 500 mm, and an aspect ratio of 5.8. Alternatively, as shown in Figure 17, each opening 31, 32 may be an opening with a vertical dimension of 8900 mm, a horizontal dimension of 500 mm, and an aspect ratio of 17.8.

[0058] In the above embodiment, the partition plate 24 blocked off each of the multiple grids 23 of the conveyor frame 21. However, the partition plate may block off two or more of the grids 23. In this case, the partition plate may be placed on the conveyor frame 21 or attached to the underside of the conveyor frame 21.

[0059] In the above embodiment, an automobile body was used as an example of the workpiece W1 to be painted in the paint booth 11, but it is not limited to this. For example, the workpiece may be an interior part of an automobile such as an instrument panel, console box, or armrest, or an exterior part of an automobile such as a bumper or aerodynamic add-on parts (spoiler, etc.). Furthermore, the workpiece W1 does not necessarily have to be an automobile part.

[0060] Next, in addition to the technical ideas described in the claims, the technical ideas that can be grasped by the embodiments described above are listed below.

[0061] (1) A dry coating apparatus characterized in that, in means 1, the aspect ratio of the opening is 2.0 or more and less than 4.0.

[0062] (2) A dry coating apparatus characterized in that, in means 1, the pitch between adjacent openings in the longitudinal direction of the booth is 1000 mm or more and 2000 mm or less.

[0063] (3) A dry coating apparatus characterized in that the aspect ratio of the opening in means 1 is 4.0 or greater.

[0064] (4) A dry painting apparatus characterized in that, in any one of the means 1 to 4, the opening is a first opening located far from the paint mist removal device and a second opening located close to the paint mist removal device, the booth air that has passed through the first opening and the booth air that has passed through the second opening become a first airflow and a second airflow, respectively, with a reduced thickness in the booth width direction, and the first airflow is supplied to the paint mist removal device by riding on the flow of the second airflow without being obstructed by the second airflow.

[0065] (5) In the technical concept of (4), the pair of side walls is a first side wall located far from the paint mist removal device and a second side wall located close to the paint mist removal device, and the first opening is installed at a distance from the first side wall.

[0066] (6) A dry coating apparatus characterized in that, in the technical concept of (4) or (5), the first opening and the second opening are arranged so as to be at equal distances from the transport path.

[0067] (7) A dry coating apparatus characterized in that, in any one of the means 1 to 4, the transport path is configured by installing a conveyor on a grid-shaped conveyor frame provided at a lower position than the breathable floor, the partition plate is supported by the conveyor frame, and the opening has an opening area smaller than the area of ​​one grid of the conveyor frame and is arranged to avoid the position of the conveyor frame by being horizontally offset.

[0068] (8) In any one of the means 1 to 4, the processing air volume is 50 m ３ / min or more 250m３ A dry coating equipment characterized by having a minimum or minimum of / min.

[0069] (9) A dry coating equipment characterized in that, in any one of the means 1 to 4, the height of the space under the booth floor is 800 mm or more and 1500 mm or less.

[0070] (10) A dry coating equipment characterized in that, in any one of the means 1 to 4, the length of the space under the booth floor is 4,000 mm or more and 8,000 mm or less.

[0071] 10: Dry painting equipment 11: Paint booth 12: First side wall as a side wall 13: Second side wall as a side wall 14: Ventilated floor section 15: Conveyor path 24: Partition plate 31: First opening as an opening 32: Second opening as an opening 40: Paint mist removal device 41: Filter 42: Filter housing B0: Booth air L1: Vertical dimension L2: Horizontal dimension M1: Paint mist S1: Painting space S2: Booth floor space W1: Workpiece

Claims

1. A dry painting apparatus comprising: a painting booth having a pair of side walls and a ventilated floor, a painting space formed above the ventilated floor, and painting while transporting the object to be painted in the painting space along a transport path extending in the longitudinal direction of the booth; and a paint mist removal device having a filter housing capable of housing a filter, which removes paint mist from the booth air by flowing booth air discharged from the painting space through the filter, wherein the paint mist removal device is installed at a position offset in the width direction of the booth and outside one of the pair of side walls, wherein a partition plate is provided at a position lower than the ventilated floor to divide the internal area of ​​the painting booth vertically, and an under-floor space of the booth is provided in the area below the partition plate which is flow-directly connected to the paint mist removal device, and openings are formed on both sides of the transport path of the partition plate to allow the booth air to flow into the under-floor space of the booth, and the openings have a vertical dimension that is long in the longitudinal direction of the booth and a horizontal dimension that is short in the width direction of the booth. The dry painting equipment is characterized in that the space under the booth floor guides the booth air that has passed through the opening in the width direction of the booth and supplies it to the paint mist removal device.

2. The dry coating equipment according to claim 1, characterized in that the aspect ratio of the opening is 2.0 or more and less than 5.

0.

3. The dry coating equipment according to claim 2, characterized in that the wind speed of the booth air passing through the opening is 0.5 m / s or more and 3.0 m / s or less.

4. The dry coating equipment according to claim 3, characterized in that the opening is a first opening located far from the paint mist removal device and a second opening located close to the paint mist removal device, and the first opening and the second opening are spaced at least 1500 mm apart.

5. The dry painting equipment according to any one of claims 1 to 4, wherein the opening is a first opening located far from the paint mist removal device and a second opening located close to the paint mist removal device, and the booth air that has passed through the first opening and the booth air that has passed through the second opening become a first airflow and a second airflow, respectively, with a reduced thickness in the booth width direction, and the first airflow is supplied to the paint mist removal device by riding on the flow of the second airflow without being obstructed by the second airflow.

6. The dry coating equipment according to any one of claims 1 to 4, characterized in that the transport path is constructed by installing a conveyor on a grid-shaped conveyor frame provided at a lower position than the breathable floor, the partition plate is supported by the conveyor frame, and the opening has an opening area smaller than the area of ​​one grid of the conveyor frame and is positioned to avoid the position of the conveyor frame by being horizontally offset.

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