JPH0857403A - Operation method for coating booth with air supply - Google Patents

Abstract

PURPOSE: To form no surface roughness nor color blushing on a film of a material to be coated in an automatic coating zone of a coating booth with air supply when the wind velocity of clean air flowed through the coating booth for the purposes of energy saving and resources saving is lowered to the minimum. CONSTITUTION: The wind velocity of clean air flowed through an unmanned automatic coating zone 7 is set to be lower than that of a manned hand spray zone, and when coaters 27-29 set in the automatic coating zone 7 are cleaned by a solvent such as thinner or when a coating material is sprayed as a trial before the start of coating by the coaters 27-29, the wind velocity of clean air is increased more than the ordinary time during the given period of time starting before the trial spraying and ending after the same.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for operating an air-supplied coating booth in which clean air sent from an air conditioner is distributed to each zone such as a coating preparation zone, a hand-blown coating zone, an automatic coating zone and a setting zone. Regarding

[0002]

2. Description of the Related Art An air-supplied coating booth for automobile coating is formed in a tunnel shape for coating while transporting an automobile body to be coated by a conveyor, and the inside thereof is a manned coating preparation zone and a hand. It is divided into a spray painting zone, an unattended automatic painting zone, and a setting zone. Then, in each of these zones, the clean air sent from the air conditioner is introduced into the zone at a predetermined wind speed through the filter of the ceiling portion, and the air in the zone is sucked and discharged below the floor through the suction floor. By doing so, it is possible to prevent a coating film defect due to the rising of the paint mist, a fire explosion accident due to the filling of the evaporated organic solvent, and to prevent the health of the worker from being impaired (JP-A-1-245874).
Issue).

In order to save energy in such a paint booth with air supply, it is desirable to reduce the amount of air supply and exhaust in each zone as much as possible to reduce the running cost of the air conditioner and the power cost of the air supply fan and the exhaust fan. Be done. Also, if the wind speed of the clean air introduced into the hand-blown coating zone or the automatic coating zone is too high, the paint sprayed from the coating machine will not be applied to the surface of the coated object but will be sucked directly into the suction floor and will be wasted. Since the amount of waste air will increase, it is desirable to reduce the wind speed of clean air in both zones in order to save resources. Here, in the manned hand-painting zone, air is supplied and exhausted so that the wind speed of the clean air flowing in the zone is 0.5 m / sec in accordance with the work environment standard established for the health maintenance of workers. However, the unattended automatic painting zone, which does not need to consider the health of workers, has a minimum required clean air speed of 0.2 m / se.
It is set to c ~ 0.4 m / sec to prevent waste of paint.

[0004]

However, if the wind speed in the automatic coating zone is constantly set to 0.2 m / sec to 0.4 m / sec, the coating film of the coated object may have rough skin or color cast. In other words, in automobile painting, a paint color is specified for each automobile body conveyed by a conveyor, and multicolor painting is performed to change the color of the paint sprayed from the painting machine according to the paint color. However, if the wind speed of the automatic coating zone is lower than that of the hand-blown coating zone, it will be sprayed on the coating machine to wash and remove the previous color paint adhering to the coating machine when changing from the previous color paint to the next color paint. The dust of the solvent or the mist of the next color paint that the painting machine made a trial spray (discard) before the start of the next color paint after the color change is finished, the finish of the previous color paint is completed and the automatic coating zone It has been found that there is a risk that it may adhere to the coating film of the article to be withdrawn and cause roughening of the coating film or color cast. In view of the above, the present invention has a technical object to reduce the supply / exhaust flow rate of a paint booth with air supply as much as possible in order to save energy and resources, and at the same time reliably prevent the occurrence of coating defects due to rough skin or color cast.

[0005]

In order to solve the above-mentioned problems, an operating method of a supply booth with air supply according to the present invention is, in a normal state, an automatic coating in which an object to be coated conveyed by a conveyor is unattended. When the wind speed of the clean air to be distributed in the zone is set lower than that of the manned hand-blown coating zone, when the coating machine installed in the automatic coating zone is washed with a solvent or when the coating machine performs a trial spraying of the paint. The air speed of the clean air flowing through the automatic coating zone is increased from the normal time for a certain period of time from before to after.

[0006]

According to the present invention, normally, the wind speed of the clean air flowing through the automatic coating zone is set lower than that of the hand-blown coating zone, and the power cost of the fan for supplying and exhausting the automatic coating zone is reduced. At the same time, the running cost of the air conditioner that supplies clean air to the automatic coating zone is also reduced. When cleaning a coating machine installed in the automatic coating zone with a solvent or when the coating machine performs a trial spray of paint, the wind speed of the clean air to be distributed to the automatic coating zone is normal during a certain time before and after that. The dust of the solvent used to wash the painting machine and the mist of the paint sprayed by the painting machine are quickly removed from the automatic painting zone.
Roughness and color cast are reliably prevented from occurring on the coating film of the coating object coated in the automatic coating zone.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a diagram showing an example of a supply booth with air supply using the operation method of the present invention.

The air-supplied coating booth shown in this example has a tunnel-shaped booth main body 2 through which a substrate 1 to be coated, which is conveyed by a conveyor, passes at a constant speed. A coating preparation zone 5, a hand-blown coating zone 6, an automatic coating zone 7 and a setting zone 8 are provided toward the side. An air supply chamber 11 to which clean air is supplied from the air conditioner 9 by the air supply fans 10a and 10b is provided in the upper part of the booth body 2, and the clean air sent to the air supply chamber 11 is supplied to the booth body 2 It is introduced into each zone 5 to 8 through a filter 12 arranged on the ceiling part inside. In addition,
In the air supply chamber 11, two places located at the front and rear ends of the automatic coating zone 7 are partitioned by partition walls 13 and 14, and clean air is fed between the partition walls 13 and 14 by an air supply fan 10b. The clean air is fed to the portion by the air supply fan 10a. Further, in the lower part of the booth body 2, exhaust processing chambers 20 to 23 are provided in which the air in the zones 5 to 8 is sucked and discharged by the exhaust fans 15 to 18 through the lattice-shaped suction floor 19.

An air supply fan 10b for supplying clean air between the partition walls 13 and 14 of the air supply chamber 11 and an exhaust fan 17 for sucking and discharging the air in the automatic coating zone 7 to the exhaust processing chamber 22.
Uses a variable speed fan whose rotation speed is variable by the inverters 24 and 25, respectively, and controls the rotation speed of the variable speed fan.
It is controlled by 6. Controller 26
Controls the operation of each of the coating machines 27, 28 and 29 installed in the automatic coating zone 7 based on input data that defines the type, shape, coating color, etc. of the article 1 to be conveyed by the conveyor, Normally, the air supply fan 10b and the exhaust fan 17 are arranged so that the clean air introduced into the automatic painting zone 7 flows through the zone 7 at a wind speed of 0.2 to 0.4 m / sec.
When the paint adhered to the coating machines 27-29 is automatically cleaned with a solvent such as thinner, or when the coating machines 27-29 spray a certain amount of paint by trial, The wind speed of clean air is reduced to 0 for a certain period of time.
Air supply fan 10 to increase to 5 to 1.0 m / sec.
The rotation speeds of b and the exhaust fan 17 are increased to a required value.

That is, in the manned hand-painting zone 6 to which clean air is supplied by the air supply fan 10a, the rotation speed of the exhaust fan 16 is set so that the clean air flows at a wind speed of 0.5 m / sec according to the working environment standard. In addition, the coating preparation zone 5 in which dust and dirt may enter from the carry-in port 3 of the article to be coated 1 and the setting zone 8 in which the solvent is flushed are also considered in consideration of their dust removal effect and flushing effect, respectively. The rotation speeds of the exhaust fans 15 and 18 are set so that the clean air flows at a wind speed of about 0.5 m / sec. On the other hand, in the unattended automatic coating zone 7, the wind speed of the clean air in the normal time is manned by the human hand in order to further save energy and to minimize the wasteful spraying of the paint to save resources. Lower than coating zone 6 0.2
The rotation speeds of the exhaust fan 17 and the air supply fan 10b are set so as to be about 0.4 m / sec.

Then, between the end of coating the preceding article 1 to be coated in the automatic coating zone 7 and the start of coating the subsequent article 1, the coating machines 27 to 29 are sprayed with a solvent. When the paint adhering to the surface or the like is removed by washing, or when the next color paint that has changed color from the previous color paint is spray-tested by each of the coating machines 27 to 29, it is supplied from the control device 26 for a certain time before and after that time. A control signal for increasing the rotation speeds of the air fan 10b and the exhaust fan 17 is output, the supply / exhaust amount of the automatic coating zone 7 is increased, and the wind speed of the clean air flowing in the zone 7 is 0.5 times or higher than the normal time. ~ 1.0m / sec
It can be raised to a certain degree.

As a result, the dust of the solvent sprayed on each of the coating machines 27 to 29 and the mist of the paint sprayed by trial from each of the coating machines 27 to 29 do not soar and float in the automatic coating zone 7. It is quickly discharged from the zone 7 through the suction bed 19 into the exhaust treatment chamber 22. Therefore, those dust and mist will not be applied to the automatic coating zone 7.
The possibility of sticking to the coating film of the article 1 to which the coating has been completed and causing rough skin or color cast on the coating film is eliminated.

In automobile coating, the automobile body to be coated 1 is usually transported at intervals of about 2 to 3 m, and the transport speed is about 4 to 7 m / min. Although the interval time from the completion of the above-mentioned painting to the start of the subsequent painting of the article to be coated is only about 20 to 30 seconds, when the painting of the preceding article is finished, the air supply fan 1
0b and the rotation speed of the exhaust fan 16 are increased, if the dust of the solvent and the mist of the paint cannot be completely discharged from the automatic coating zone 7 within the interval time, the coating of the preceding coating object is completed. It is possible to increase the supply / exhaust amount in the automatic coating zone 7 by increasing the rotation speeds of the air supply fan 10b and the exhaust fan 16 before the completion of the coating, without waiting for the coating. That is, if the air supply / exhaust volume of the automatic coating zone 7 is increased before the coating of the article 1 to be coated to increase the wind speed of the clean air flowing in the zone 7, the amount of wasted spray of the coating is slightly increased. 0.5-1.0m immediately before
If it is only increased to about / sec, the amount of wasteful blowing will be small, and there is no risk of impairing coating quality.

The coating booth shown in FIG. 1 is provided with a hand-blown coating zone 6 in the front stage of the automatic coating zone 7. However, the coating booth according to the present invention has a post-correction coating in the rear stage of the automatic coating zone. A hand-blown coating zone for performing the above may be provided. The automatic painting zone is not limited to the reciprocating painting zone where a side machine or top machine is installed, but also includes a robot painting zone where a manipulator is installed.

Further, in the coating booth according to the present invention, it is sufficient that at least the wind speed of the clean air circulating in the automatic coating zone can be variably controlled independently of the other zones. For example, as shown in FIG. Not only the exhaust fans 15 to 18 are provided for each of the zones 5 to 8, but a small air conditioner and an air supply fan may be provided to each of the zones. In addition, if the coating booth is equipped with a damper that can individually adjust the air volume and speed of the clean air introduced into each zone along the ceiling of the automatic painting zone, the exhaust air can be exhausted from each zone 5 to 8 as shown in Fig. 1. Even if the structure is such that one exhaust fan exhausts each zone collectively without providing the fans 13 to 16, the wind speed of the clean air flowing to the automatic painting zone can be changed independently of other zones. can do.

[0016]

According to the present invention, in order to save energy and resources, even if the wind speed of the clean air flowing through the unattended automatic coating zone is reduced to the minimum, the coating failure due to the rough surface or color cast of the coating film can be prevented. It has a very excellent effect that it does not occur, and if it is applied to an air-supplying painting booth for automobile painting where a large amount of air supply and exhaust of 10,000 m ³ / min or more in the entire booth is applied, a car with a high-quality coating is required. It is possible to achieve energy saving and resource saving without impairing the coating quality of
It is very useful.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a paint booth with air supply using an operating method of the present invention.

[Explanation of symbols]

 1 ... Object to be coated 6 ... Hand-blown coating zone 7 ... Automatic coating zone 27 ... Painting machine 28 ... Painting machine 29 ... Painting machine

Claims (1)

[Claims] 1. At a normal time, the wind speed of clean air that is circulated in an automatic coating zone (7) for unattended coating of an article (1) conveyed by a conveyor is higher than that of a manned hand-blown coating zone (6). When the coating machine (27-29) installed in the automatic coating zone (7) is set low and washed with a solvent, or when the coating machine (27-29) sprays the paint, The automatic coating zone (7) for a certain time after the fact.
A method for operating a paint booth with air supply, characterized in that the wind speed of the clean air that is circulated to the air is increased more than usual.