JP4129756B2 - Powder coating booth - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a powder coating booth that performs powder coating by suspending an object to be coated inside.
[0002]
[Prior art]
A painting booth that performs powder coating on a deformed pipe such as a ductile cast iron pipe is basically a box with one side open, and coating is performed from this open side. The dust collector is generally provided on the side opposite to the open surface that coats the object to be coated, that is, on the back side as viewed from the operator, and the air flows from the back of the worker to the back of the booth. It comes to flow. Powder coating is characterized by higher coating efficiency compared to solvent-based coating. However, in order to further improve coating efficiency and reduce coating costs, extra paint (overspray) has been used. Attempts have been made to collect and reuse.
[0003]
There are roughly three types of dust collection (recovery) methods in this type of painting booth. FIG. 4 is an explanatory view of the dust collection method in the conventional booth B. The object to be coated in the booth is coated from the opening on the left side of the figure, and the air is drawn in the direction of the arrow from the inlet K provided at the right end of the figure. To collect dust. 4 (a) is for collecting dust from the top and bottom center of booth B, FIG. 4 (b) is for collecting dust from the bottom of booth, and FIG. 4 (c) is a combination of these types. Dust is collected from the center and bottom of the booth.
[0004]
However, these conventional dust collection methods have the following problems. First, dust collecting from the upper and lower central parts of the booth shown in FIG. 1 (a) can obtain a relatively uniform film thickness, but the air flow in the lower part of the booth is poor and efficient dust collection is difficult. In addition, dust collecting from the bottom of the booth shown in FIG. 5 (b) can collect dust relatively efficiently, but it has an air flow that promotes falling of powder that is heavier than air. In order to make it, there exists a problem that the film thickness of the lower part will become thick compared with the upper part of to-be-coated object. On the other hand, the combined type shown in FIG. 2C can compensate for the above-mentioned disadvantages to some extent, but it cannot be said that the coating can be performed sufficiently efficiently and uniformly, which is a fundamental solution. Has not reached.
[0005]
In a typical paint line to be painted while continuously transferring the object to be coated, usually, it is often painted suspended article to be coated P hook of the chain conveyor through the top upper part. In such a coating line, as shown in FIG. 3, the chain conveyor C is passed over the booth B, and the hook H is suspended in the booth through a slit provided in the ceiling of the booth.
[0006]
In powder coating of a deformed tube, so-called hot coating is generally performed in which powder to be coated is heated to about 200 ° C. For this reason, the air around the painted object is warmed, and an upward air flow from the painted object P toward the ceiling of the booth B is generated. The flow rate of the ascending airflow is 1.0 to 1.5 m / sec at the position 500 mm above the coated object, although it depends on the size of the coated object and the temperature of the coated object.
[0007]
On the other hand, with the suction capacity of ordinary dust collectors and recovery devices used in powder coating booths, the flow velocity of the airflow around the coating is only 0.1 to 0.5 m / sec. If body painting is performed, the paint is wound up by the rising air current, passes through the slit of the booth ceiling, and enters the chain conveyor section. Since the paint that has entered the conveyor section contaminates the conveyor and its surroundings, there has been a problem that maintenance is troublesome.
[0008]
In order to prevent the paint wound up by the updraft from entering the chain conveyor from the slit, it is conceivable to increase the flow velocity of the air flowing from the slit of the booth ceiling. Even if the suction capacity of the dust collector and recovery device is increased, the flow rate of air flowing in through the slits in the ceiling will not be so high due to the structure, and only the flow rate of air flowing in from the booth opening on the painting side is more than necessary. The powder coating that adheres to the object to be coated is reduced. As a result, the coating efficiency is deteriorated, and the amount of powder paint for the overspray increases. Conversely, when the suction capacity of the recovery device is small, not only the recovery efficiency is lowered, but also the problem that the sprayed powder coating material returns to the hand and the workability is deteriorated occurs.
[0009]
As a method for preventing the powder coating material from entering the chain conveyor, in addition to the above, a method of forcibly sending air from the slit of the booth ceiling can be considered. However, in this method, if the distance from the paint to the booth ceiling is not more than a certain value, the ascending air current in the booth interferes with the forced air and a turbulent air current is generated. There is no problem if the booth ceiling can be made relatively high, but turbulence tends to occur if the booth ceiling cannot be made high due to restrictions such as the ceiling height of the installation location. Since this turbulent air flow is a factor that adversely affects the painting, the flow velocity of the air forced from the booth ceiling slit must be reduced, and as a result, the desired effect is often not obtained.
[0010]
[Problems to be solved by the invention]
As described above, in the conventional painting booth, the coating efficiency is reduced due to the improvement of the suction capacity of the recovery device, and the film thickness is reduced. However, if the discharge amount of the powder is increased to increase the film thickness, This amount exceeded the suction capacity of the recovery device, resulting in a decrease in recovery efficiency and deterioration in workability. On the other hand, when the suction capacity of the recovery device is improved to improve the recovery efficiency and workability, the coating efficiency is lowered. For this reason, in the structure of the conventional painting booth, it was difficult to improve the coating efficiency, the recovery efficiency, the workability, etc. at the same time. Therefore, the present invention solves the problems in the conventional painting booth by making the suction flow rate of the powder paint recovery device of the painting booth adjustable , and passes through a slit for hanging the hook in the painting booth. The problem is to solve the problems caused by the paint flowing into the conveyor .
[0011]
[Means for Solving the Problems]
In order to solve the above problems, the present invention employs the following configuration. In other words, painting booth according to the present invention the front side opening of the paint chamber, paint recovery device is provided on the rear side, the ceiling component in a hook for hanging into the paint booth through a slit formed in the ceiling In a powder coating booth provided with a conveyor for suspending and transferring the object to be coated, a vertical partition panel having a vent hole whose opening degree can be adjusted is provided between the coating position of the object to be coated and the recovery device. In addition, between the ceiling and the upper part of the painting room, a partition part formed with a slit for suspending the hook of the conveyor in the painting room is provided along the ceiling. wherein the opening portion side to the collecting apparatus forming an air passage through which air flows, elevated paint through the slit of the partition portion is circulated to the recovery unit side through the air flow path It is characterized in that have configured so.
[0012]
It is preferable to provide an air flow passage through which air flows from the coating chamber in which the object is to be coated to the collection device side at the bottom of the coating booth. It is more effective if the opening amount of the air flow passage can be adjusted.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described more specifically based on embodiments of the present invention shown in the drawings.
[0014]
As shown in FIGS. 1 and 2, the painting booth 1 is formed in a box shape by the ceiling 2, the bottom 3, the back panel 4, and the left and right side walls 5 and 6, and the front side surface becomes an opening 7. A paint gun 8 is provided in the part. On the upper side of the ceiling 5 of the booth 1, there is provided a chain conveyor 10 which is a device for transferring an object to be coated. The chain conveyor 10 is housed in a groove-shaped housing 11 in the left-right direction, and a slit 12 is formed at the bottom of the housing, that is, the booth ceiling. The chain conveyor 10 is provided with a hook 15 that hangs down in the painting booth. Reference numeral 16 denotes a rod for connecting the chain conveyor 10 and the hook 15. The chain conveyor housing 11 is provided with vent holes 13 communicating with the outside.
[0015]
The interior of the painting booth 1 is divided into a painting room 1a and a collection room (chamber) 1b by a partition panel 20. The partition panel 20 is formed in a side-view key shape including a horizontal partition portion 21 and a vertical partition portion 22, and the horizontal partition portion 21 is disposed below the ceiling 2 of the booth 1 with an interval therebetween. An air flow passage 23 through which airflow flows is formed. The horizontal partition 21 is provided with a similar slit 24 immediately below the slit 12, and the hook 15 is suspended in the coating chamber 1 a through the slits 12 and 24.
[0016]
A lattice-shaped ventilation window 26 in which elongated slit-shaped ventilation holes 25 are formed in the vertical center of the vertical portion 22 of the partition panel 20 is provided. A sliding panel 29 having a plurality of slit-shaped ventilation holes 27,... Formed at the same pitch as the ventilation holes 25,... It is fixed in place. The sliding panel 29 is a means for adjusting the opening degree of the ventilation window portion 26. When the slit-like ventilation holes 27 are fixed so as to completely overlap the slit-like ventilation holes 25 of the ventilation window portion, the painting chamber is provided. A large amount of air in 1a circulates in the collection chamber 1b through the ventilation window and the slit-like ventilation holes of the sliding panel. Further, the amount of airflow flowing through this portion can be adjusted by adjusting the overlapping state between the slit-like vent holes 25 of the ventilating window portion 26 and the slit-like vent holes 27 of the slide type panel. When the slide type panel is fixed so that the two slit-like vent holes are completely staggered, there is almost no air flow from the coating chamber 1a to the recovery chamber 1b passing through this portion.
[0017]
The bottom portion 3 of the painting booth 1 is formed in a table shape that slightly rises from the floor surface. Between the bottom portion 3 and the lower end portion of the vertical portion 22 of the partition panel 20, a painting chamber 1a and a collection chamber 1b are provided. A communicating air flow passage 30 is formed. The opening degree of the air flow passage 30 can be adjusted by a vertical slide type shutter 32 attached to the partition panel 20. A blower-type recovery device 35 that sucks and recovers the powder coating material together with air is installed inside the recovery chamber 1b. The paint sucked by the collecting device 35 is separated from air by a separating device such as a filter, and the air is discharged out of the booth. Further, the collected powder coating material is sent to the coating gun 8 through a regeneration processing apparatus (not shown) and reused.
[0018]
The side walls 5 and 6 on both the left and right sides of the painting booth 1 are formed with openings through which the object is to be coated. The openings are opened and closed by a sliding door 40. The chain conveyor 10 carries an object to be coated into the painting chamber from an opening provided on one side wall 5 of the painting booth 1 and unloads the object to be coated from the opening of the other side wall 6. At the time of loading and unloading, the sliding door 40 on the side wall is opened and closed during the painting operation.
[0019]
When the object to be coated (in the illustrated example, a deformed pipe) P is to be painted in the painting booth 1, the deformed pipe P is heated to a predetermined coating temperature and is suspended by a hook 15 in a coating chamber 10 by a chain conveyor 10. Carry in 1a. In the illustrated example, two deformed tubes can be coated at the same time. When the object to be coated is carried in, the sliding door 40 on the side wall of the booth is closed, and spray painting is performed with the painting gun 8 in a state where the collecting device 35 is operated.
[0020]
The painting booth 1 has a double ceiling structure, and air is constantly flowing from the opening 7 side to the collection chamber 1b side through the ceiling part. Even if it rises, it is carried to the recovery chamber by the air flow toward the recovery chamber and is recovered by the recovery device 35. Therefore, the paint hardly enters the position of the chain conveyor 10. Moreover, since the distribution port which leads from the coating chamber 1a to the collection chamber 1b is provided in two places, the upper and lower center portion (ventilation window portion 26) and the bottom portion (flow passage 30), the opening degree can be adjusted. By adjusting, the state of the airflow in the booth can be adjusted according to the length, shape, coating conditions, etc. of the coated object. For this reason, a stable and uniform coating film can be obtained.
[0021]
The shape and size of the ventilation hole of the ventilation window 26 and the opening degree adjusting means are not limited to those shown in the drawings, and may be appropriate according to the use conditions. For example, a perforated plate having a large number of round or square holes can be used as the panel instead of the elongated slit. In the illustrated example, two objects to be coated are applied at the same time. However, only one object may be applied, or three or more objects may be simultaneously applied.
[0022]
【The invention's effect】
As described above, the painting booth according to the present invention can efficiently suck the paint for the overspray while keeping the suction speed of the entire booth within the range that does not adversely affect the painting, and the capacity of the recovery device is also improved. There is no need to make it bigger than necessary. Moreover, it became possible to prevent the coating material from entering the conveyor portion provided on the ceiling portion by generating an airflow that flows to the collection device side with the ceiling portion having a double structure.
[Brief description of the drawings]
FIG. 1 is a side sectional view of a painting booth according to the present invention.
FIG. 2 is a front view thereof.
FIG. 3 is a side sectional view of a conventional painting booth.
FIG. 4 is an explanatory diagram of a dust collection method in a conventional painting booth.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Coating booth 2 Ceiling part 3 Bottom part 4 Back panel 7 Opening part 10 Chain conveyor 12 Slit 15 Hook 22 Partition panel 23 Air flow path 25 Slit 26 Ventilation window part 30 Air flow path 35 Recovery apparatus P Deformation pipe (to-be-coated object)

Claims (2)

And the front side opening of the painting chamber, on the far side paint recovery device is provided in the ceiling portion partial transferring hung the article to be coated in a hook hanging down into the painting booth through the slit formed in the ceiling conveyor In the powder coating booth provided with a vertical partition panel having a vent opening adjustable between the coating position of the object to be coated and the recovery device, and between the ceiling and the upper part of the coating chamber In the meantime, by providing a partition along the ceiling with a slit for suspending the hook of the conveyor in the painting chamber, from the opening to the collection device side between the partition and the ceiling powder coating for forming an air passage through which air flows, characterized in that the elevated paint through the slit of the partition portion have configured so as to circulate to the recovery unit side through the air flow passage Booth.   The powder coating booth according to claim 1, wherein an air flow passage through which air flows from the coating chamber side to the collecting device side is also provided at the bottom of the coating chamber.

Images