JP4787575B2 - Painting equipment and painting method - Google Patents

Description

  The present invention relates to a painting facility and a painting method, and more particularly, to an application device equipped with a painting gun for spraying paint, an air for ejecting evaporation promoting air for promoting evaporation of a paint solvent in the spray paint from the painting gun. The present invention relates to a painting facility and a painting method in which an ejection means is provided.

Conventionally, as this kind of painting equipment and painting method, an air duct as an air jetting means is used in a rotary atomizing coating machine as a painting gun installed in a painting apparatus (for example, painting robot) installed in a painting booth. Equipped with a plurality of air outlets arranged in a circle on the outer periphery of the cylindrical body of the rotary atomizing coater. Evaporation-promoting air is ejected from the air duct in a state of surrounding the outer periphery of the flight area (hereinafter sometimes referred to as a spray pattern) toward the paint, and the temperature in the spray pattern is controlled by the evaporation-promoting air. Accelerates the evaporation of the paint solvent in the spray pattern, and the solid content rate of the coating on the object is moderately adjusted regardless of the temperature around the coating device (that is, the temperature in the coating booth) Coating Technology applied to the object to be coated are known. (See Patent Document 1 below)
In this technique, the temperature of the evaporation promoting air ejected from the air duct is set according to the temperature and humidity conditions of the air in the painting booth.
JP 2000-325860 A

In recent years, the use of a build-to-order manufacturing method is increasing for the purpose of improving the overall efficiency from production to sales. This build-to-order method does not produce one type of product sequentially on one production line, but sequentially produces various types of products according to the order status on one production line. It has the excellent advantage of saving labor in organizing work.
And in the painting equipment, with the view of adopting such a custom-made production system with such advantages, it depends on multiple paint types such as water-based paint using water as paint solvent and solvent paint using organic solvent such as thinner as paint solvent. There is a need to support mixed-flow painting where painting is performed on the same painting line.

  However, in the prior art as described above in which the temperature of the evaporation promoting air is set according to the temperature and humidity conditions around the coating apparatus, in the case of performing mixed flow coating with a plurality of paint types having different evaporation speeds of the paint solvent, for example, water is used as the paint solvent. Water-based paints (water-based paints) and solvent-based paints (solvent paints) that use organic solvents that evaporate more easily than water as paint solvents. ) Evaporation is moderate and the solids content of the coating is moderately adjusted. However, in solvent coating, the evaporation of the coating solvent (organic solvent) by the evaporation promoting air is excessive and the solids content of the coating is excessive. Therefore, there is a problem that it is not possible to cope with the switching of the paint type in the mixed flow coating, for example, the coating quality is deteriorated.

  The present invention has been made in view of the above-mentioned problems, and its main problem is to effectively solve the above-described problems by rational improvements.

To achieve the above tasks,
In a painting facility equipped with a painting device equipped with a painting gun for spraying paint, equipped with air ejection means for ejecting evaporation promoting air to promote the evaporation of the paint solvent in the spray paint from the painting gun ,
A structure in which a plurality of objects to be transported by a transport means are sequentially applied by spraying paint from the paint gun, and the temperature of the evaporation promoting air is automatically switched according to the type of paint for each object to be coated. Means may be provided.

In other words, with this configuration , the temperature of the evaporation promoting air is automatically switched according to the type of paint for each object to be transported by the transport means. The acceleration can be made moderate and the solid content ratio of the coating film can be made moderate, and this makes it possible to stably produce a high-quality coated product even in mixed flow coating.

  By the way, as another painting facility that stably produces high-quality paint even in mixed-flow coating, for example, in the case of mixed-flow coating that performs water-based coating and solvent coating, the solvent in which the coating solvent evaporates more easily than aqueous coating It is also conceivable to stop the evaporation-enhancing air jet depending on the type of paint, such as suppressing the evaporation of the paint solvent in solvent coating by stopping the ejection of evaporation-enhancing air from the air blowing means during painting. In contrast, the present invention, by ejecting evaporation promoting air whose temperature is changed according to the paint type, allows the flying speed of the paint particles toward the object to be coated irrespective of the change of the paint type in the mixed flow coating. There is an advantage that it is possible to avoid the fact that the coating state changes greatly depending on the presence / absence of evaporation promoting air, while avoiding that it varies greatly depending on the presence or absence of evaporation promoting air. .

In implementing this configuration,
By disposing the air ejection part of the air ejection means along the periphery of the paint spraying part in a front view with respect to the paint spraying part of the paint gun, the air spraying part is directed to the coating object of the paint particles sprayed from the paint spraying part. You may make it the structure which ejects the said evaporation promotion air in the state surrounding the outer periphery of a flight area .

In other words, with this configuration , the spray pattern is shielded from the air around the coating apparatus by surrounding the outer periphery of the flight area (that is, the spray pattern) of the paint particles toward the object to be coated with the evaporation promoting air. It is possible to suppress the intrusion of impurities into the spray pattern, which can suppress the occurrence of coating defects such as impurities mixed into the coating film, and the coating quality in mixed flow coating Can be made higher.

In the implementation of the above configuration,
A plurality of types of air having different temperatures are mixed by an air mixing unit, and the mixed air is jetted from the air jetting unit as the evaporation promoting air.
The switching means may be configured to switch the temperature of the evaporation promoting air by changing a mixing ratio of a plurality of types of air having different temperatures .

  That is, for example, it is possible to switch the temperature of the evaporation promoting air by increasing or decreasing the amount of air heated by the heater, but in that case, against the increase or decrease of the amount of air heated by the heater. There is a considerable time delay until the temperature of the evaporation promoting air changes, and this causes the switching of the temperature of the evaporation promoting air to be delayed.

On the other hand, with this configuration , the temperature of the evaporation promoting air is switched by changing the mixing ratio in the air mixing means of a plurality of types of air having different temperatures, so that the temperature can be switched quickly. This makes it possible to ensure high coating efficiency in mixed flow coating.

In implementing this configuration,
You may provide the said air mixing means in the said coating apparatus or the position close | similar to it .

In other words, with this configuration , the evaporation promoting air mixed and generated by the air mixing means can be ejected from the air ejecting means equipped in the coating apparatus with the movement distance being as short as possible. The air can be ejected from the air ejecting means in a short time, and the temperature of the evaporation promoting air can be switched more rapidly. This makes it possible to ensure a higher coating efficiency in the mixed flow coating.

  Further, as described above, since the generated evaporation promoting air can be ejected from the air ejecting means in as short a time as possible, it is possible to suppress the temperature decrease as much as possible by radiating the evaporation promoting air while moving. In addition, the temperature accuracy of the evaporation promoting air ejected from the air ejecting means can be increased, and thereby the coating quality in the mixed flow coating can be further improved.

In contrast to these configurations, the first characteristic configuration of the painting equipment according to the present invention is:
A painting facility equipped with a painting gun equipped with a painting gun for spraying paint, equipped with air ejection means for ejecting evaporation promoting air for promoting the evaporation of the paint solvent in the spray paint from the painting gun,
A structure in which a plurality of objects to be transported by a transport means are sequentially applied by spraying paint from the paint gun, and the temperature of the evaporation promoting air is automatically switched according to the type of paint for each object to be coated. Providing means,
A plurality of types of air having different temperatures are mixed by an air mixing unit, and the mixed air is jetted from the air jetting unit as the evaporation promoting air,
The switching means is configured to switch the temperature of the evaporation promoting air by changing a mixing ratio of plural types of air having different temperatures.
In the plural types of air having different temperatures, the temperature of the evaporation promoting air is switched in a state where the lower limit of the mixing ratio of the high temperature side air is limited to a value larger than 0.

With this first characteristic configuration, as described above, the temperature of the evaporation promoting air is automatically switched according to the type of paint for each object conveyed by the conveying means. It is possible to moderate the acceleration of paint solvent evaporation and the solid content ratio of the coating film, which enables stable production of high-quality coatings even in mixed-flow coating. .
In addition, since the temperature of the evaporation promoting air is switched by changing the mixing ratio of air of different types at different air mixing means, the temperature can be quickly switched. High efficiency can be secured.
And, for example, when switching the temperature of the evaporation promoting air from the high temperature side to the low temperature side, it may be possible to temporarily set the mixing ratio of the high temperature side air among the plural types of air to 0, The high-temperature side air stays in the air supply path for supplying the high-temperature side air to the air mixing means and dissipates the heat. When switching to, high-temperature side air whose temperature has decreased due to heat radiation is mixed by the air mixing means, which slows switching of the temperature of the evaporation promoting air to the high-temperature side.

On the other hand, in the case of the first characteristic configuration described above, the temperature of the evaporation promoting air in a state where the lower limit of the mixing ratio of the high temperature side air is limited to a value larger than 0, that is, in a state where the high temperature side air is always mixed. Therefore, it is possible to prevent the high-temperature side air from staying in the air supply path and dissipating heat, thereby enabling the temperature of the evaporation promoting air to be quickly switched to the high-temperature side. In addition, the coating efficiency in the mixed flow coating can be further ensured.
The second feature configuration of the present invention specifies an embodiment suitable for the implementation of the first feature configuration.
By disposing the air ejection part of the air ejection means along the periphery of the paint spraying part in a front view with respect to the paint spraying part of the paint gun, the air spraying part is directed to the coating object of the paint particles sprayed from the paint spraying part. The evaporation promoting air is ejected in a state of surrounding the outer periphery of the flight area.
According to the second characteristic configuration, as described above, the outer periphery of the flight area (that is, the spray pattern) toward the coating object of the paint particles is surrounded by the evaporation promoting air, so that the spray pattern is separated from the air around the coating apparatus. It can be in a state to be shielded, can suppress the intrusion of impurities into the spray pattern, and this can suppress the occurrence of coating defects such as impurities mixed into the coating film, The coating quality in the mixed flow coating can be further improved.
The third feature configuration of the present invention specifies an embodiment suitable for the implementation of the first or second feature configuration.
The air mixing means is provided at or near the coating apparatus.
According to the third characteristic configuration, as described above, the evaporation promoting air mixed and generated by the air mixing means can be ejected from the air ejecting means equipped in the coating apparatus in a state where the moving distance is as short as possible. Evaporation-promoting air can be ejected from the air ejection means in as short a time as possible, and the temperature of the evaporation-promoting air can be switched more quickly, thereby ensuring a higher painting efficiency in mixed-flow coating. Can do.
Further, since the generated evaporation promoting air can be ejected from the air ejecting means in as short a time as possible, it is possible to suppress the temperature decrease due to the heat radiation of the evaporation promoting air during movement as much as possible. The temperature accuracy of the evaporation promoting air ejected from the means can be increased, and this can further improve the coating quality in the mixed flow coating.

The fourth feature configuration of the present invention specifies a preferred embodiment in the implementation of the first to third feature configurations.
The state in which the high temperature side air is passed through the high temperature side air supply path for supplying the high temperature side air among the plurality of types of air having different temperatures to the air mixing means is temporarily stopped from spraying the paint from the coating gun. Is in a configuration that continues .

  That is, for example, when the spray of paint from the coating gun is temporarily stopped, such as when the paint type is changed (or when the color is changed) or when the object is transported, the high temperature side air supply path is stopped by stopping the ejection of the evaporation promoting air. It is also possible to interrupt the state in which the high temperature side air is ventilated, but in that case, the high temperature side air stays in the high temperature side air supply path and dissipates heat, so that the temperature of the high temperature side air decreases. When the spraying of paint from the paint gun is resumed, the high temperature side air whose temperature has been reduced is mixed by the air mixing means, which generates evaporation promoting air at a predetermined temperature according to the paint type. It will be late.

On the other hand, in the fourth characteristic configuration described above, since the high temperature side air continues to flow through the high temperature side air supply path even during the temporary suspension of paint spraying, the high temperature side air becomes the high temperature side air supply path. It is possible to suppress a decrease in the temperature of the high-temperature side air by staying and dissipating heat, and it is possible to quickly generate evaporation-promoting air having a predetermined temperature according to the type of paint when resuming paint spraying. As a result, it is possible to ensure a high coating efficiency even in mixed-flow coating in which paint spraying needs to be temporarily stopped, and it is possible to provide a coating facility that can easily handle mixed-flow coating in various paint types and production processes. .

The fifth feature configuration of the present invention specifies a preferred embodiment in the implementation of the fourth feature configuration.
The high temperature side air that is ventilated to the high temperature side air supply path during the temporary stop of the spraying of the paint from the coating gun is configured to be discharged to the outside from a discharge unit that is different from the air jetting unit.

  That is, for example, in order to continue the state in which the high-temperature side air is passed through the high-temperature side air supply path even during the suspension of paint spraying, the high-temperature side air that is ventilated through the high-temperature side air supply path during the suspension of paint spraying is evaporated. Although it is conceivable that the air is ejected from the air ejection means as the accelerating air, in that case, unnecessary evaporation accelerating air that is not related to the evaporation of the coating solvent is blown against the object being transported, etc. There is a risk that coating failure such as disturbance of the coating film may occur.

On the other hand, if it is the above-mentioned fifth characteristic configuration, the high-temperature side air that is ventilated to the high-temperature side air supply path during the temporary stop of paint spraying is discharged to the outside from a discharge unit that is different from the air blowing means. By spraying unnecessary evaporation-promoting air on the object being transported, it is possible to prevent coating failure such as turbulence of the coating film. This makes it necessary to suspend paint spraying. The coating quality can be improved, and it is possible to provide a coating facility that can easily cope with various types of coatings and mixed-flow coating in production processes.

The sixth feature configuration of the present invention specifies a preferred embodiment in the implementation of the first to fifth feature configurations.
The plurality of types of air having different temperatures are heated air and room temperature air.

In other words, with this sixth feature configuration, one of the airs having different temperatures is room temperature air that does not require a heater, so that a dedicated heater for generating the one air can be dispensed with. Therefore, the complication of the painting equipment can be suppressed.

The seventh characteristic configuration of the present invention relates to a coating method,
A painting method equipped with a coating device equipped with a coating gun for spraying paint, equipped with an air ejection means for ejecting evaporation promoting air for promoting the evaporation of the paint solvent in the spray paint from the coating gun,
With sequentially coated by paint spray from the spray gun several article to be coated is conveyed by the conveying means, it switches the temperature of the steam promoter air depending on the coating type of each article to be coated,
A plurality of types of air having different temperatures are mixed, and the mixed air is ejected from the air ejection means as the evaporation promoting air,
While changing the temperature of the evaporation promoting air by changing the mixing ratio of a plurality of types of air having different temperatures,
It is in the point which switches the temperature of the said evaporation promotion air in the state which restricted the minimum of the mixing ratio of high temperature side air to the value larger than 0 among the multiple types of air from which the said temperature differs .

In other words, with this seventh characteristic configuration, the temperature of the evaporation promoting air is switched according to the type of paint for each object conveyed by the conveying means. The acceleration can be made moderate and the solid content ratio of the coating film can be made moderate, and this makes it possible to stably produce a high-quality coated product even in mixed flow coating.

By the way, as another coating method that stably produces high-quality coatings even in mixed-flow coating, for example, in the case of mixed-flow coating in which aqueous coating and solvent coating are performed, the solvent in which the coating solvent evaporates more easily than aqueous coating. It is also conceivable to stop the evaporation-enhancing air jet depending on the type of paint, such as suppressing the evaporation of the paint solvent in solvent coating by stopping the ejection of evaporation-enhancing air from the air blowing means during painting. In contrast, the present invention, by ejecting evaporation promoting air whose temperature is changed according to the paint type, allows the flying speed of the paint particles toward the object to be coated irrespective of the change of the paint type in the mixed flow coating. There is an advantage that it is possible to avoid the fact that the coating state changes greatly depending on the presence / absence of evaporation promoting air, while avoiding that it varies greatly depending on the presence / absence of evaporation promoting air. .
Further, with the seventh feature configuration, as described above, the temperature of the evaporation promoting air is switched by changing the mixing ratio of the plural types of air at different temperatures in the air mixing means. This makes it possible to ensure high coating efficiency in mixed flow coating.
In addition, as described above, the temperature of the evaporation promoting air is switched in a state where the lower limit of the mixing ratio of the high temperature side air is limited to a value larger than 0, that is, in a state where the high temperature side air is always mixed. It is possible to prevent the high-temperature side air from staying in the air supply path and dissipating heat, and this enables quick switching of the temperature of the evaporation promoting air to the high-temperature side. Higher efficiency can be secured.

The eighth feature configuration of the present invention specifies a preferred embodiment in the implementation of the seventh feature configuration.
By disposing the air ejection part of the air ejection means along the periphery of the paint spraying part in a front view with respect to the paint spraying part of the paint gun, the air spraying part is directed to the coating object of the paint particles sprayed from the paint spraying part. The evaporation promoting air is ejected in a state of surrounding the outer periphery of the flight area.

In other words, with this eighth characteristic configuration, the spray pattern is shielded from the air around the coating apparatus by surrounding the outer periphery of the flight area (that is, the spray pattern) toward the object to be coated with the evaporation promoting air. It is possible to reduce the intrusion of impurities into the spray pattern, which can prevent the occurrence of coating defects such as impurities entering the coating film, and the mixed flow coating. The coating quality in can be made higher.

The ninth feature configuration of the present invention specifies an embodiment suitable for the implementation of the seventh or eighth feature configuration.
The state in which the high temperature side air is passed through the high temperature side air supply path for supplying the high temperature side air among the plurality of types of air having different temperatures to the air mixing means is temporarily stopped from spraying the paint from the coating gun. Is also a point to continue.

With this ninth feature, as described above, the high temperature side air continues to flow through the high temperature side air supply path even during the temporary suspension of paint spraying, so the high temperature side air stays in the high temperature side air supply path. The heat dissipation can suppress the temperature of the high-temperature side air from decreasing, and when the spraying of the paint is resumed, the evaporation promoting air having a predetermined temperature according to the paint type can be quickly generated. Thus, high coating efficiency can be ensured even in mixed-flow coating in which paint spraying needs to be temporarily stopped, and it is possible to provide a coating facility that can easily cope with mixed-flow coating in various paint types and production processes.

The tenth characteristic configuration of the present invention specifies an embodiment suitable for the implementation of the ninth characteristic configuration.
The high temperature side air that is ventilated through the high temperature side air supply path during the temporary stop of the spraying of paint from the coating gun is discharged to the outside from a discharge unit that is different from the air blowing means.
If it is this 10th characteristic structure, since the said high temperature side air ventilated to the high temperature side air supply path during the temporary stop of paint spraying is discharged | emitted outside from the discharge part different from an air ejection means as mentioned above, it is conveyed. By spraying unnecessary evaporation-promoting air on the object to be coated, it is possible to prevent coating defects such as turbulence of the coating film, and in this case, in mixed-flow coating where paint spraying needs to be temporarily stopped. In addition, the coating quality can be improved, and it is possible to provide a coating facility that can easily cope with various types of coatings and mixed-flow coating in production processes.

The eleventh characteristic configuration of the present invention specifies a preferred embodiment in the implementation of the seventh to tenth characteristic configurations.
Heated air and room temperature air are used as the plurality of types of air having different temperatures.

In other words, with this eleventh feature configuration, room temperature air that does not require a heater is used for one of the airs having different temperatures, so that a dedicated heater for generating the one air can be eliminated. Therefore, the complication of the painting equipment can be suppressed.

  FIG. 1 shows a painting facility constructed by using a painting facility and a painting method of the present invention, 1 is a tunnel-like painting booth (plan view), 2 is an object to be coated (automobile body in this embodiment), and painting In the booth 1, a plurality of painting robots 3 are installed that automatically and sequentially coats the workpiece 2 that is tact-conveyed at predetermined intervals by the conveying means T.

  The lower surface of the painting robot 3 is provided with a plurality of rolling wheels 3b that can roll on a rail 3a of a predetermined length that is laid on the floor surface of the painting booth 1 in parallel with the conveying line of the article 2 to be coated. 2 is configured to be movable within a predetermined range in the conveying direction of the coating robot 3, and paint is sprayed onto the work arm 3 c of the coating robot 3 in the form of a mist on the workpiece 2 and simultaneously with the spraying of the paint. An air shield nozzle-integrated coating machine 4 for jetting shield air as evaporation promotion air, which will be described later, toward the object to be coated 2 is provided, and this coating machine 4 is operated by the operation of the work arm 3c or a wheel. By moving by rolling on the rail of 3b, the arbitrary coating site | part of the to-be-coated article 2 is painted.

  Reference numeral 9 denotes a heater for each coating machine 4 that heats the normal temperature air A1 supplied from the air supply source to generate the coating heating air A2, and 8A denotes the coating heating air A2 in the vicinity of the coating booth 1. This is a long high-temperature side air supply pipe that is supplied to the air supply header 7 for each of the coating machines 4 arranged in (1). Although not shown, the outer periphery is covered with a heat insulating material over its entire length. Reference numeral 8B denotes a low-temperature side air supply pipe that guides normal temperature air A3 (same air as A1) supplied from an air supply source to the vicinity of the coating booth 1, and the other end of the coating booth 1 side is connected with other members. A flange-shaped joint is provided for connection.

  Reference numeral 5 denotes a plurality of (two in this embodiment) high-temperature side air supply hoses for supplying the heating air A2 for coating supplied to the supply header 7 through the high-temperature side air supply pipe 8A to each coating machine 4. , 6 is a low-temperature side air supplied to each coating machine 4 as a normal temperature air A3 for painting by connecting the normal-temperature air A3 led to the vicinity of the coating booth 1 by the low-temperature side air supply pipe 8B with a joint with the low-temperature side air supply pipe 8B. Supply hose. These high-temperature side and low-temperature side air supply hoses 5 and 6 are each made of a flexible resin that allows the coating machine 4 to move.

  The connecting pipe 14 extending from the air supply source to the heater 9 is provided with a high temperature side air supply valve 10, and by operating the high temperature side air supply valve 10, the heating air A2 for painting to the coating machine 4 is supplied. The supply flow rate can be adjusted. A low-temperature side air supply pipe 8B extending from the air supply source to the low-temperature side air supply hose 6 is provided with a low-temperature side air supply valve 11. The supply flow rate of the room temperature air A3 for coating to 4 can be adjusted.

  12 is a valve controller for each coating machine 4 that automatically operates the air supply valves 10 and 11 on the high temperature side and the low temperature side in cooperation with the switching of the supply paint to the coating machine 4 based on a preset production schedule. The coating heating air A2 and the coating normal temperature air A3, whose flow rates are adjusted by the valve operation by the valve controller 12, are supplied to the coating machine 4.

  2 and 3 show a coating machine 4 mounted on the work arm 3c, 4A is a bullet-shaped paint gun attached to the work arm 3c, and 4a is a rotating bell as a paint spraying portion provided at the tip of the paint gun 4A. There is a paint discharge port 4b in the center of the rotary bell 4a as viewed from the front.

  At the front end portion of the coating gun 4A, a small-shaped shaping air outlet 4c for ejecting the shaping air As toward the object 2 side (that is, the front side desired by the rotating bell 4a) is provided in front of the rotating bell 4a. A number of coating particles formed in a ring shape around the rotating bell 4a as viewed and discharged from the outer edge of the rotating bell 4a in an atomized state by being discharged from the coating material discharge port 4b and rotating at a high speed. As shown schematically in FIG. 4, the air travels toward the object 2 in the spray pattern P where the outline is formed by the jet flow of the shaping air As, and is applied to the object 2.

  Reference numeral 4B denotes an air shield nozzle as an air jetting means provided at the tip of the work arm 3c together with the coating gun 4A. The air shield nozzle 4B is slightly behind the rotating bell 4a (that is, the side to be coated). The annular nozzle portion 4e is provided as an air ejection portion arranged along the periphery of the rotating bell 4a in a state separated from the coating gun 4A and surrounding the coating gun 4A, and the nozzle portion 4e supports the nozzle. It is connected and fixed to the vicinity of the tip of the work arm 3c via the member 4d.

A plurality of high temperature side air supply hoses 5 for supplying the coating heating air A2 and a low temperature side air supply for supplying the coating normal temperature air A3 are provided in the nozzle support member 4d in the vicinity of the connecting portion with the nozzle portion 4e. The hose 6 is connected from the rear side, and the heating air A2 for coating supplied from the air supply hoses 5 and 6 and the room temperature air A3 for coating are mixed, and the mixed air A2 and A3 are projected from the front side. Equipped with a mixer 13 as air mixing means to be supplied to the nozzle portion 4e through the delivery pipe 13a. By installing this mixer 13, the heating air A2 for painting and the painting air are operated by the valve controller 12. By adjusting the normal temperature air A3 to the respective supply flow rates, the mixing ratio of the coating heating air A2 and the coating normal temperature air A3 in the mixer 13 is changed, and the temperature of the mixed air A2 and A3 is changed. It is to be adjusted.
In addition, 13b is a silencer (silencer) equipped in the connection part with respect to the nozzle part 4e of the delivery pipe | tube 13a in the mixer 13. FIG.

  The nozzle portion 4e is connected to a nozzle support member 4d by a bolt and connected from the rear surface side to the nozzle tube body 4f connecting the delivery pipe 13a of the mixer 13, and a lid-like body 4g attached to the front surface portion of the nozzle portion body 4f. An annular nozzle portion having an annular air chamber 4h therein by attaching a lid-like body 4g to the front surface portion of the nozzle portion body 4f in a state where it covers the annular recess of the forward opening formed in the nozzle portion body 4f. 4e is formed, and the mixed air A2 and A3 are supplied to the annular air chamber 4h via the mixer 13.

The lid 4g of the nozzle portion 4e is provided with a shield air outlet 4i for ejecting the mixed air A2 and A3 supplied to the annular air chamber 4f as the shield air Ah toward the article 2 to be rotated. In the front view with respect to 4a, it forms with the arrangement | positioning located cyclically | annularly along the circumference | surroundings of the cyclic | annular arrangement | positioning part of the shaping air ejection port 4c.

Then, the shield air Ah (that is, the temperature-adjusted mixed air A2 and A3) is ejected from the shield air ejection port 4i to form the shaping air As from the rotating bell 4a as schematically shown in FIG. The outer periphery of the spray pattern P to be surrounded is surrounded by the jet flow of the shield air Ah (in other words, the spray pattern P is shielded from the indoor air of the painting booth 1 by the shield air Ah). The intrusion of impurities into the inside is suppressed to prevent the occurrence of coating defects such as the impurities being mixed into the coating film, and the shield air Ah is mixed into the spray pattern P in the flow process so that the spray pattern P The internal temperature is adjusted by the shield air Ah, so that the vapor of the paint solvent in the spray paint is sprayed in the spray pattern P. Suppressing the occurrence of coating defects such as sagging and unevenness by moderately solid fraction of the coating film immediately after coating to promote.

  As shown in FIG. 5, the temperature of the shield air Ah is determined by the automatic operation of the high-temperature side air supply valve 10 and the low-temperature side air supply valve 11 by the valve controller 12, as shown in FIG. It is designed to automatically switch between three patterns: a standby pattern in a state where painting is not performed, and a solvent coating pattern in which an organic solvent such as thinner is used as a paint solvent. In the aqueous coating pattern, the flow rate Ra2 of the coating heating air A2 is set to The flow rate is higher than the flow rates Rb2 and Rc2 in the standby pattern and the solvent coating pattern, and the flow rate Ra3 of the coating room temperature air A3 is smaller than the flow rates Rb3 and Rc3 in the standby pattern and the solvent coating pattern (this embodiment) In the embodiment, the flow rate is set to zero), so that the temperature Ta of the shield air Ah is changed to the standby pattern and the solvent coating pattern. Therefore, the internal temperature TA of the spray pattern P is higher than the internal temperatures TB and TC of the standby pattern and the solvent coating pattern (for example, 60 ° C.). For example, at 36 ° C., the evaporation of water, which is a paint solvent that is harder to evaporate than an organic solvent, is promoted.

In the solvent coating pattern, the flow rate Rc2 of the heating air A2 for coating is set to a flow rate slightly higher than half the flow rate Ra2 in the aqueous coating pattern, and the flow rate Rc3 of the room temperature air A3 for coating is higher than the flow rate Ra3 in the aqueous coating pattern. and a large flow rate, the shield air Ah temperature Tc to a temperature lower than the temperature Ta in the aqueous coating pattern (e.g., 42 ° C.) to, also, the total flow rate of paint heated air A2 and paint cold air A3 aqueous The flow rate is made slightly smaller than the flow rate in the coating pattern, whereby the internal temperature TC of the spray pattern P is set to a temperature (for example, 27 ° C.) lower than the internal temperature TA in the aqueous coating pattern, and the amount of ejection of the shield air Ah To a certain extent to promote the evaporation of the organic solvent to some extent.

  That is, a water-based coating is applied to the conveyed workpiece 2 in a state in which evaporation of the paint solvent (water) is promoted by the shield air Ah of the aqueous coating pattern, and another coating to be subjected to the subsequent solvent coating is applied. For the coating 2, the heating air A <b> 2 for painting in the mixer 13 by adjusting the flow rates of the heating air A <b> 2 for painting and the room temperature air A <b> 3 for painting by automatic operation of the air supply valves 10, 11 by the valve controller 12. And by applying the shield air Ah automatically switched to the solvent coating pattern by changing the mixing ratio of room temperature air A3 for coating, solvent coating can be performed in a state that accelerates the evaporation of the paint solvent (organic solvent) to some extent, On the other hand, the coated object 2 is solvent-coated in a state in which evaporation of the paint solvent (organic solvent) is promoted to some extent by the shield coating air Ah of the solvent coating pattern, and then the conveyed water For another object 2 to be coated, water-based coating can be performed in a state in which evaporation of the paint solvent (water) is promoted by the shield air Ah automatically switched to the water-based coating pattern as described above. Thus, the solid content rate of the coating film can be made appropriate regardless of the change of the kind of paint.

  In addition, the shield air Ah suppresses the entry of impurities into the spray pattern P during coating regardless of the coating type, such as aqueous coating and solvent coating, by ejecting the shield air Ah in each of the aqueous coating pattern and the solvent coating pattern. As a result, the occurrence of coating defects such as impurities mixed into the coating film is avoided, and the flying speed of the paint particles toward the article 2 to be coated depending on the type of paint, such as water-based paint or solvent paint, is increased depending on whether or not the shield air Ah is ejected. By avoiding the difference, it is also possible to prevent the state of the coated film from being greatly different depending on whether or not the shield air Ah is ejected.

In the standby pattern, the flow rate Rb2 of the coating heating air A2 and the flow rate Rb3 of the coating normal temperature air A3 are set to the same flow rate as the solvent coating pattern, and the temperature Tb of the shield air Ah and the internal temperature TB of the spray pattern P are set. Is set to the same temperature as the solvent coating pattern.

  That is, in all of the aqueous coating pattern, the standby pattern, and the solvent coating pattern, the mixing ratio of the coating heating air A2 in the mixer 13 is limited to a value greater than 0 (in other words, the coating is performed in the mixer 13). The high-temperature side air supply path (specifically, the high-temperature side air supply pipe 8A and the high-temperature side air) extending from the heater 9 to the mixer 13 by ejecting the shield air Ah generated in the state where the heated air A2 is always mixed. The temperature of the coating heating air A2 is radiated by the heat generated when the coating heating air A2 stays in the high-temperature side air supply path so that fresh coating heating air A2 is always passed through the supply hose 5). Is reduced by mixing the fresh coating heating air A2 in which the temperature decrease is suppressed in this manner with the mixer 13 provided in the coating machine 4 to generate the shield air Ah. Regardless of the presence or absence of the pattern, it is possible to quickly generate the shield air Ah having the temperature of the water-based coating pattern and the solvent coating pattern, and the shield air Ah generated by the mixer 13 is applied to the coating machine in the same manner as the mixer 13. By ejecting from the air shield nozzle 4B provided in the nozzle 4, the shield air Ah at the required temperature can be ejected in as short a time as possible.

As shown in FIGS. 6 to 8, a plurality of high-temperature side air supply hoses 5 that supply the heating air A <b> 2 for coating to the mixer 13 provided in the coating machine 4 are covered hoses that surround the outer periphery of the air supply hoses 5. 5d is provided, and a double hose structure is formed in which a heat-retaining space S having an annular shape in cross section is formed over the entire length of the air supply hose 5 between the inner peripheral surface of the covering hose 5d and the outer peripheral surface of the air supply hose 5. The heat insulation air layer SA is formed inside the heat insulation space S.
The covering hose 5d is made of a flexible resin that allows the coating machine 4 to move, like the air supply hose 5.

  And, in the vicinity of the coating machine 4 side end of the high temperature side air supply hose 5 (specifically, in the vicinity of the connection part with the mixer 13), the inside of the air supply hose 5 passes through the end of the coating machine 4 side. A small first discharge port 5a for discharging a part of the heating air A2 for coating (approximately 10% of the total flow rate in the present embodiment) from the air supply hose 5 and introducing it into the heat insulation space S is provided. In the vicinity of the air supply header 7 of the covering hose 5d located outside the coating booth 1, a plurality of the warming air A4 in the heat insulating space S is discharged to the outside of the covering hose 5d. A plurality of small second discharge ports 5c are arranged in the circumferential direction, so that a part of the coating heating air A2 introduced into the heat retaining space S through the first discharge ports 5a is heated. Passing of heating air A2 for painting inside the air supply hose 5 as A4 After passing toward the air supply header 7 which is opposite to the kiln, the heat supply air A4 is discharged from the heat insulation space S to the outside of the painting booth 1 through the second discharge port 5c. A heat insulation air layer SA that suppresses external heat radiation from the coating heating air A2 inside the hose 5 is formed in the heat insulation space S.

  That is, the air supply by the movement of the coating machine 4 is maintained by keeping the heating air A2 for painting inside the air supply hose 5 in the warming air layer SA that has passed through the warming air A4 that is an intangible having almost no deformation resistance. Suppressing a decrease in the heat retention effect due to the deformation of the hose 5, thereby keeping the heat retention effect for the coating heating air A2 high for a long period of time, and shielding the coating heating air A2 due to a decrease in the temperature retention effect. It suppresses the temperature accuracy of the air Ah from decreasing, keeps the coating quality high, minimizes the decrease in the flexibility of the air supply hose 5 due to the heat retention, and reduces the resistance of movement of the coating machine 4 The reduction of the operation efficiency of the painting robot 3 and the painting machine 4 due to becoming is suppressed.

  Further, in the cross sectional view, the air supply hose 5 is surrounded by the heat insulation space S over almost the entire circumference thereof, so that the heat radiation from the coating heating air A2 inside the air supply hose 5 can be radiated from the heat insulation air layer SA. However, the heat on the side that radiates heat from the coating heating air A2 to the heat insulation air layer SA by forming the heat insulation air layer SA with the heat insulation heating air A4 that is higher than the room temperature air is suppressed. When the amount of exchange is made as small as possible, and the heat-retaining heating air A4 is passed through the heat-retaining space SA, the heat-retaining air A4 stays in the heat-retaining air layer SA and dissipates heat, thereby lowering the temperature. The temperature of the heat-retaining air layer SA is kept as low as possible, and the heat of the coating heating air A2 inside the air supply hose 5 is effectively maintained.

The outer peripheral surface of the high temperature side air supply hose 5 has a truncated pyramid shape in side view with a height h smaller than the difference R between the radius R1 of the inner peripheral surface of the covering hose 5d and the radius R2 of the outer peripheral surface of the air supply hose 5. A plurality of resin spacers 5b are arranged at regular intervals in the circumferential direction (four in every 90 degrees in this embodiment), and a spacer group consisting of the plurality of circumferentially arranged spacers 5b is arranged in the hose length direction. A plurality of groups are provided at predetermined intervals, and the warming air A4 passes between the spacers 5b adjacent in the circumferential direction and between the inner peripheral surface of the covering hose 5d and the ceiling surface of the spacer opposite to the inner surface. The spacer 5b is in contact with the inner peripheral surface of the coating hose 5d outside the outer peripheral surface of the air supply hose 5 so that the elasticity of the air supply hose 5 when the coating machine 4 moves is bent. Empty in deformation The supply hose 5 and the covering hose 5d are prevented from coming into contact with each other, and thereby the thickness of a part of the heat insulation air layer SA in the circumferential direction is reduced, or the heat insulation air layer SA is a part of the circumferential direction. It is prevented from becoming inexistent, and it is possible to suppress the heat insulation efficiency from being lowered due to heat radiation from these parts and the passage of these parts to the passage of the heat insulation heating air A4.

  In the present embodiment, the valve controller 12 and the air supply valves 10 and 11 constitute switching means for switching the temperature of the shield air Ah.

  Further, in the present embodiment, the heating air A2 for coating and the heating air A4 for heat insulation are not limited to those having the same composition as the air in the outside air, and any composition as long as they are intangible gases. There may be.

[Another embodiment]
Next, other embodiments of the present invention will be listed.
In the above-described embodiment, the shield air Ah having a standby pattern in which the mixing ratio of the coating heating air A2 in the mixer 13 is larger than 0 is ejected even during standby when the painting is not performed, such as when changing colors. The heating of the coating air A2 was continued to flow through the high-temperature side air supply path, but the spraying of the shield air Ah was temporarily stopped during standby, and the coating heating air A2 in the high-temperature side air supply path was temporarily stopped. Is exhausted to the outside of the high temperature side air supply path through the discharge portion including the first discharge port 5a, the covering hose 5d, and the second discharge port 5c, thereby continuing the ventilation of the coating heating air A2 to the high temperature side air supply path. You may make it the structure to make.

  In the above-described embodiment, the mixer 13 is provided in the painting robot 3, but it may be provided near the painting robot 3, such as in the painting booth 1.

  In the above-described embodiment, the valve controller 12 automatically operates the high-temperature and low-temperature air supply valves 10 and 11 in cooperation with the switching of the supply paint to the coating machine 4 based on a preset production schedule. However, it may be configured to cooperate with the temperature around the painting robot 3.

  In the above-described embodiment, the shield air Ah is shown as an example of the evaporation promotion air. However, the present invention is not limited to this, and for example, the shaving air As may be set to promote the evaporation of the paint solvent. In other words, regardless of whether it is direct or indirect, any air may be used as long as it is used for promoting evaporation of the paint solvent.

  In the above-described embodiment, the example in which the heat insulation air layer SA is configured to pass the heat insulation heating air A4 through the heat insulation space S has been described. However, the heat insulation space S may be configured to have air sealed. .

  In the above-described embodiment, the example in which the heated air A4 for heat retention is discharged to the outside through the second discharge port 5c of the covering hose 5d has been shown, but the heated air A4 for heat retention is not discharged to the outside and is resupplied to the supply header 7 You may make it the structure to carry out.

Configuration diagram of painting equipment Partially cutaway sectional view of a coating machine with integrated air shield nozzle Front view of an air shield nozzle integrated painting machine Side view schematically showing paint spray state Table for explaining the relationship between the supply flow rate of coating heated air, the supply flow rate of normal temperature air for coating, the temperature of shield air, and the temperature in the spray pattern Longitudinal view of the hot air supply hose II sectional view of FIG. II-II line sectional view of FIG.

T Transport means 2 Object 3 Coating robot (painting equipment)
4A Paint gun 4a Rotating bell (Paint spraying part)
4B Air shield nozzle (air jetting means)
4e Nozzle part (air ejection part)
A2 Heating air for painting (high temperature side air, heated air)
A3 Normal temperature air for coating (normal temperature air)
5 High temperature side air supply hose (High temperature side air supply path)
5a 1st discharge port (discharge part)
5c 2nd discharge port (discharge part)
5d Coated hose (discharge section)
8A High temperature side air supply pipe (High temperature side air supply path)
10 High-temperature side air supply valve (switching means)
11 Low temperature side air supply valve (switching means)
12 Valve controller (switching means)
13 Mixer (Air mixing means)

Claims (11)

A painting facility equipped with a painting gun equipped with a painting gun for spraying paint, equipped with air ejection means for ejecting evaporation promoting air for promoting the evaporation of the paint solvent in the spray paint from the painting gun,
A structure in which a plurality of objects to be transported by a transport means are sequentially applied by spraying paint from the paint gun, and the temperature of the evaporation promoting air is automatically switched according to the type of paint for each object to be coated. setting means,
A plurality of types of air having different temperatures are mixed by an air mixing unit, and the mixed air is jetted from the air jetting unit as the evaporation promoting air,
The switching means is configured to switch the temperature of the evaporation promoting air by changing a mixing ratio of plural types of air having different temperatures.
A coating facility configured to switch the temperature of the evaporation promoting air in a state where the lower limit of the mixing ratio of the high temperature side air is limited to a value larger than 0 among the plurality of types of air having different temperatures .   By disposing the air ejection part of the air ejection means along the periphery of the paint spraying part in a front view with respect to the paint spraying part of the paint gun, the air spraying part is directed to the coating object of the paint particles sprayed from the paint spraying part. The painting facility according to claim 1, wherein the evaporation promoting air is jetted out so as to surround an outer periphery of a flight area. The painting equipment according to claim 1 or 2, wherein the air mixing means is provided at the painting device or at a position close thereto . The state in which the high temperature side air is passed through the high temperature side air supply path for supplying the high temperature side air among the plurality of types of air having different temperatures to the air mixing means is temporarily stopped from spraying the paint from the coating gun. The coating equipment according to any one of claims 1 to 3, wherein the coating equipment is configured to continue . 5. The high-temperature side air that is ventilated through the high-temperature side air supply path during a temporary stop of spraying of paint from the coating gun is discharged from a discharge unit that is different from the air jetting unit. Painting equipment. The coating equipment according to any one of claims 1 to 5, wherein the plurality of types of air having different temperatures are heated air and room temperature air . A painting method equipped with a coating device equipped with a coating gun for spraying paint, equipped with an air ejection means for ejecting evaporation promoting air for promoting the evaporation of the paint solvent in the spray paint from the coating gun,
A plurality of coating objects conveyed by the conveying means are sequentially applied by spraying paint from the coating gun, and the temperature of the evaporation promoting air is switched according to the type of paint for each object to be coated,
A plurality of types of air having different temperatures are mixed, and the mixed air is ejected from the air ejection means as the evaporation promoting air,
While changing the temperature of the evaporation promoting air by changing the mixing ratio of a plurality of types of air having different temperatures,
The coating method which switches the temperature of the said evaporation promotion air in the state which restricted the minimum of the mixing ratio of high temperature side air to the value larger than 0 among the multiple types of air from which the said temperature differs. By disposing the air ejection part of the air ejection means along the periphery of the paint spraying part in a front view with respect to the paint spraying part of the paint gun, the air spraying part is directed to the coating object of the paint particles sprayed from the paint spraying part. The coating method according to claim 7, wherein the evaporation promoting air is ejected in a state of surrounding an outer periphery of a flight area. The state in which the high temperature side air is passed through the high temperature side air supply path for supplying the high temperature side air among the plurality of types of air having different temperatures to the air mixing means is temporarily stopped from spraying the paint from the coating gun. The coating method according to claim 7 or 8, which is also continued . The coating method according to claim 9, wherein the high temperature side air that is ventilated to the high temperature side air supply path during a temporary stop of spraying of the paint from the coating gun is discharged to the outside from a discharge unit that is different from the air jetting unit . The coating method according to any one of claims 7 to 10, wherein heated air and room temperature air are used as the plurality of types of air having different temperatures .

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