JPS63123460A - Method for washing painting apparatus - Google Patents

Abstract

PURPOSE:To efficiently perform washing through a fluid mixture containing air bubbles, by continuously supplying compressed air into a paint supply passage at first and subsequently supplying a solvent such as a thinner only for predetermined time along with compressed air to perform washing. CONSTITUTION:For example, in the washing work of the first pipeline 74, when pipelines 68a-68d are respectively blocked under the driving action of a paint change-over means 62 and compressed air is supplied to a pipeline 70b through a regulator 72b, compressed air is supplied into a first pipeline 74 under the action of a change-over means 66b and led out to the outside from a pipeline 92 through a discharge valve 80. After the elapse of a predetermined time, a change-over valve 66a is driven to supply the thinner having predetermined pressure supplied from a regulator 72a through a pipeline 70a into the first pipeline 72 along with compressed air. Whereupon, air bubbles are generated in the fluid mixture of the thinner and compressed air and adhered paint is washed off by impact force generated when said air bubbles are destructed upon the collision with said paint.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for cleaning a coating device, and more specifically, when changing the coating material for various different objects to be coated, or when finishing a coating operation, the coating gun is cleaned. A mixed fluid of a solvent such as thinner and air is passed through a pipe for supplying a specified paint to the pipe, and the paint remaining in the pipe is extremely efficiently removed using a small amount of solvent. The present invention relates to a cleaning method for coating equipment that makes it possible to effectively clean the coating equipment.

Generally, in the automobile industry, painting apparatuses are employed to paint the outer panels of automobile bodies. In this case, the painting equipment has come to be automated to correspond to the line production process, and generally, multiple painting guns are installed and the painting equipment is connected to the car body to be painted. The vehicle body is automatically coated by spraying predetermined paint from the plurality of paint guns while moving the paint guns.

By the way, when the painting operation by the painting device is completed, the paint remains attached to the pipe line for feeding the paint to the paint gun. For this reason, the paint remaining in the pipe hardens and blocks the pipe, resulting in the inconvenience that the paint cannot be reliably sprayed when a new painting operation is performed.

Furthermore, in the factory, automobiles of various different colors are assembled, and the painting apparatus sprays different paints corresponding to the respective car bodies to perform painting work on the car bodies. In this case, when replacing the paint with a different color paint in the painting equipment, if there is paint remaining after painting in the pipe connected to the paint gun, this remaining paint will be replaced. A drawback arises in that the new paint is mixed in, making it impossible to perform a good painting job on the car body.

Therefore, as mentioned above, when finishing a painting job and when replacing the paint sprayed from the paint gun with a new, different paint, cleaning work inside the pipeline for feeding the paint to the paint gun is necessary. There is a need to do.

Therefore, in order to clean the inside of the paint supply pipe constituting the coating equipment, various cleaning methods have been conventionally used. are connected, and by switching the respective valves, thinner and compressed air are alternately supplied into the pipe line. For this reason, the paint remaining inside the pipe is dissolved with thinner, and then the dissolved paint is discharged to the outside via supplied compressed air to clean the inside of the pipe.

However, as described above, since thinner and air are alternately supplied into the pipe, it takes a considerable amount of time to clean the pipe. In particular, in the case of automatic painting equipment that is equipped with multiple painting guns, such as the automatic painting equipment described above, a considerable amount of time is spent cleaning the painting equipment, making it difficult to construct an efficient painting line system. A problem arises that makes it impossible. Moreover, since a large amount of thinner is used during the cleaning process, there is a disadvantage that it is not economical.

The present invention has been made to overcome the above-mentioned disadvantages. First, compressed air at a predetermined pressure is continuously supplied into the paint supply pipe, and then a solvent such as thinner is supplied for a desired period of time. By simultaneously feeding the compressed air into this pipe, the solvent and compressed air mix to form bubbles, and when the bubbles collide with and destroy the paint remaining in the pipe. the paint is easily removed through the impact force of;
It is an object of the present invention to provide a method for cleaning a coating device that allows the inside of a pipe to be cleaned extremely efficiently in a short period of time, and that also makes it possible to reduce the amount of solvents such as thinner used as much as possible. purpose.

In order to achieve the above object, the present invention provides a cleaning method for cleaning the inside of a pipe connected to a coating gun constituting a coating apparatus and for supplying a predetermined paint to the coating gun, comprising:
First, compressed air is introduced into the pipe, and then, while the compressed air is being supplied, a cleaning solvent is passed through the pipe for a predetermined period of time, and the cleaning solvent is passed through the mixed fluid of the solvent and compressed air. The method is characterized in that the inside of the pipe is cleaned.

Next, a method for cleaning a coating apparatus according to the present invention will be described in detail below with reference to the accompanying drawings, citing preferred embodiments in relation to an apparatus for carrying out the method.

In FIG. 1, reference numeral 10 indicates an automobile painting line, and this painting line 10 is divided into a first stage 10a, a second stage 10b, a third stage 10c, and a fourth stage 10d according to the work process. be done. In this case, the coating device 12 for carrying out the cleaning method according to the present invention is arranged at the third stage 10c.

In the first stage 10a, the engine compartment and trunk compartment of the vehicle body 14 are painted. That is, rail sections 16a and 16b are arranged on both sides of the first stage 10a, and painting robots 18a to 18d are movably arranged on these rail sections 16a and 16b. Furthermore, a bonnet opening/closing mechanism 20 and a trunk opening/closing mechanism 22 are provided in the first stage 10a. Note that a vehicle body transport mechanism 24 is provided in the center of the painting line 10 from the first stage 10a to the fourth stage 10d.

In the second stage 10b, the inner surface of the door of the vehicle body 14 and the like are painted. In this case, rail parts 26a and 26b are arranged on both sides of the second stage 10b, and painting robots 28a and 28b are movably arranged on these rail parts 26a and 26b. Further, between the vehicle body transport mechanism 24 and the rail parts 25a, 26b, there are further rail parts 30a, 3.
0b, and a door opening/closing mechanism 323, 32b is movably arranged on these rail parts 30a, 30b.

Next, in the third stage 10c, the outer panel portions of the vehicle body 14, including the hood, trunk cover, roof, and doors, are painted via the painting device 12. Then, in the fourth stage lOd, the painted vehicle body 14 is dried. It is assumed that in the first stage 10a to the third stage 10c, static electricity is applied to the paint to perform electrostatic painting on the vehicle body 14, which is the object to be painted.

Therefore, in FIGS. 1 and 2, the coating device 12 has rail sections 35a and 35b arranged in parallel on both sides of the vehicle body transport mechanism 24, an upper coating mechanism 36 that runs along the rail sections 35a, and an upper coating mechanism 36 that runs along the rail sections 35a. It basically consists of a left side painting mechanism 38 and a right side painting mechanism 40 that runs along the rail section 35b.

The upper painting mechanism 36 includes a casing 42, and a pivot arm 44 is supported on the casing 42. In this case, the pivot arm 44 is configured to be freely displaceable in the vertical direction, and is also rotatable about the pivot shaft 46 . Furthermore, a horizontal gun arm 48 is held at the end of the swing arm 44, and this horizontal gun arm 48 engages with a cylinder (not shown) provided within the swing arm 44, so that it can be freely displaced in the horizontal direction. Horizontal gun arm 48
The gun support bars 50a to 50d are held perpendicular to the horizontal gun arm 48 at predetermined intervals. Painting guns 52a to 52d are attached to the lower ends of gun support bars 50a to 50d while being spaced apart from each other by a predetermined distance. In addition, the painting guns 52a to 52d
Nozzle portions 54a to 54d are provided at the tip end side.

The left side painting mechanism 38 and the right side painting mechanism 40 are connected to the vehicle body 1.
The left side and right side of 4 are painted, and they are basically configured the same. Therefore, the left side painting mechanism 38
will be described in detail below, and a detailed description of the right side painting mechanism 40 will be omitted.

That is, the left side painting mechanism 38 includes a casing 56, and a gun arm 58 is configured to be freely displaceable in the vertical and horizontal directions under the action of an actuator (not shown) provided in the casing 56. Painting guns 60a to 60d are attached to the gun arm 58 at a predetermined distance from each other, and in this case, each of the painting guns 60a, 60b, and 60d is configured to be swingable. The coating gun 60c is fixed with its tip oriented horizontally.

Next, the painting guns 52a to 52d and 60a to 6
The piping condition at 0d is schematically shown in FIG.

In this case, the painting guns 52a to 52d and 60a
The piping of the painting gun 52a will be described in detail below, and the description of the piping configurations of the other painting guns 52b to 52d and 60a to 60d will be omitted.

That is, in FIG. 3, reference numeral 62 indicates a paint changing means, and the paint changing means 62 has switching valves 64a to 64.
4d as well as 66a and 66b. One ends of pipe lines 68a to 68d are connected to the switching valves 64a to 64d, respectively, and predetermined paint supply sources (not shown) are connected to the other ends of the pipe lines 68a to 68d, respectively. On the other hand, the switching valve 66a,
One end of the pipe lines 70a, 70b is connected to the regulator 76b, and the other end of the pipe line 70a, 70b is connected to the regulator 7.
2a and 72b, the regulator 72a is connected to a cleaning solvent supply source (not shown), such as a thinner supply source, and the other regulator 72b is connected to a compressed air supply source (not shown).

Therefore, the first pipe line 7 for supplying the paint is connected to the paint exchange means 62.
4 is connected, and this first pipe line 74 is connected to the paint injection valve 7.
8 and a discharge valve 80.

A second pipe line 8 for supplying paint to the paint injection valve 78
2 is connected, and the coating gun 5 is connected to this second pipe line 82.
2a are connected. Further, switching valves 86a and 86b are connected to the paint injection valve 78 via a pipe 84, and pipes 88a and 88b are connected to the switching valves 86a and 86b, respectively. The conduit 88a communicates with a regulator 90a, which is connected to a thinner supply source (not shown).

On the other hand, the other conduit 88b is similarly connected to a regulator 90b, which communicates with a compressed air supply source (not shown). Note that a pipe line 92 is connected to the discharge valve 80.
One end of the pipe line 92 is connected to a waste liquid treatment section (not shown).

The coating apparatus for carrying out the cleaning method according to the present invention is basically constructed as described above, and its operation and effects will be explained next.

First, the bonnet of the vehicle body 14 transported to the first stage 10a by the vehicle body transport mechanism 24 is opened by the bonnet opening/closing mechanism 20, and the trunk cover is opened by the trunk opening/closing mechanism 22.

Then, the engine room and the trunk room are painted by the painting robots 18a to 18d that travel along the rail sections 16a and 16b.

Next, the vehicle body 14 with the bonnet and trunk cover closed by the bonnet opening/closing mechanism 20 and trunk opening/closing mechanism 22 is transported to the second stage 10b by the vehicle body transport mechanism 24.

In the second stage 10b, the door of the vehicle body 14 is opened by the door opening/closing mechanism 32a, 32b, and the inner surface of the door is moved along the rail parts 26a, 26b of the painting robot 2.
Next, the door opening/closing mechanism 3 is painted by 8a and 28b.
The vehicle body 14 with its doors closed by the doors 2a and 32b is transported to the third stage 10c by the vehicle body transport mechanism 24.

Therefore, in advance, the painting guns 52a to 52d attached to the upper coating mechanism 36 are arranged so as to face the front panel of the vehicle body 14, and the coating guns 60a to 60d attached to the side coating mechanisms 38.40 are placed in the vehicle body. It is positioned in accordance with the side shape of No. 14. Then, the upper coating mechanism 36 is moved in the direction of arrow C along the rail portion 35a, and the rotating arm 44 is displaced in the vertical direction and rotated about the rotating shaft 46 while applying paint from the coating guns 52a to 52d. It is sprayed to paint the upper part of the vehicle body 14 in a striped pattern.

On the other hand, the side painting mechanisms 38, 40 are displaced a predetermined distance from the upper painting mechanism 36 along the rail portions 35a, 35b, and the respective painting guns 60a to 60d are moved while displacing the gun arm 58 in the horizontal direction. The paint is sprayed from the side surface of the vehicle body 14 to form a striped coating.

Next, after displacing the gun arm 58 by a predetermined amount in the vertical direction and setting the angular positions of the painting guns 60a to 60d, the both side painting mechanisms 38 and 40 are moved to the rail parts 35a and 35.
5b in the opposite direction. that time,
The paint sprayed from the paint guns 60a to 60d is applied to the vehicle body 1.
The liquid is sprayed onto the parts to be painted on the sides of the vehicle body 14, and the entire side of the vehicle body 14 is coated.

In addition, in the upper coating mechanism 36, the horizontal gun arm 48
is displaced by a predetermined amount in the horizontal direction, and the paint is injected onto the portion to be painted in the upper part of the vehicle body 14 via the painting guns 52a to 52d while displacing the upper painting mechanism 36 in the opposite direction along the rail portion 35a. Then, the painting work on the entire outer panel of the vehicle body 14 is completed.

In this way, the vehicle body 14 that has been painted is transported to the fourth stage 10d via the vehicle body transport mechanism 24, and then subjected to a drying process.

Therefore, after finishing the painting work on the car body 14 in the painting line IO, or when changing the paint to be injected to perform the painting work on a different type of car body 14, the cleaning work of the painting apparatus 12 is performed by the method of the present invention. .

That is, when the respective pipe lines 68a to 68d are cut off from the first pipe line 74 under the driving action of the paint changing means 62 and compressed air at a predetermined pressure is supplied to the pipe line 70b via the regulator 72b, the compressed air is supplied into the first conduit 74 under the action of the switching valve 66b.

The compressed air flowing through the first conduit 74 is led out to the outside via the conduit 92 under the action of the discharge valve 80.

Then, after a predetermined period of time has elapsed, the switching valve 66a is actuated to transfer the thinner at a predetermined pressure supplied from the regulator 72a via the pipe 70a to the first pipe 74 together with the compressed air.
Send it inside. Therefore, the thinner and compressed air coexist, and bubbles are formed in the mixed fluid of the thinner and compressed air. When the bubbles collide with and destroy the paint adhering to the inside of the first pipe line 74, the paint is easily dissolved and removed from the inner wall surface of the first pipe line 74 through the impact force. .

Further, after a predetermined period of time has elapsed, if the switching valve 66a is driven to stop the supply of thinner and only compressed air is fed into the first pipe line 74, the paint is dissolved in the first pipe line 74. is suitably discharged to the outside from the conduit 92 via the discharge valve 80.

In this way, the first pipe line 74 is cleaned, and the second pipe line 82 is started to be cleaned.

That is, by driving the switching valve 86b, the regulator 90b is
When compressed air is supplied from the pipe 84 through the pipe 88b to the second pipe 82, this compressed air passes through the second pipe 82 and is injected to the outside from the painting gun 52a. be done.

Next, after a predetermined period of time has elapsed, the switching valve 86a is driven to supply thinner at a predetermined pressure from the regulator 90a to the pipe line 84 through the pipe line 88a, and this thinner is mixed with the compressed air and the second It passes through the pipe line 82. At this time, similarly to the first pipe line 74, the paint adhering to the inside of this second pipe line 82 is dissolved and removed and is sprayed to the outside from the coating gun 52a.

Furthermore, if the switching valve 86a is driven to stop the supply of thinner to the second pipe line 82, only compressed air will pass through the second pipe line 82. The melted paint is effectively removed to the outside from the paint gun 52a through the compressed air.

After finishing the cleaning work of the first pipe line 74 and the second pipe line 82, the switching valves 55a, 66b and 86a186b are driven to clean the respective pipe lines 7Qa, 70b and 88a, 88.
b and the pipes 74 and 82 are cut off from communication. Among the pipes 68a to 68d, for example, pipe 6
By driving the switching valve 64b connected to the pipe line 68
A predetermined paint is sent to the pipe line 74.82 from b, and this paint is injected from the paint gun 52a to perform a painting operation on a new object to be painted.

As described above, the pipes 82 and 74 connected to the painting gun 52a
Although the cleaning work has been described, it is easily understood that the cleaning work of the unillustrated pipes connected to the other painting guns 52b to 52d and 60a to 60d is performed in the same way.

In this case, according to the present invention, the cleaning work of each pipe line 74, 82 can be carried out in an extremely short time and efficiently compared to the conventional method, and the amount of thinner used can be reduced as much as possible, resulting in a remarkable It becomes possible to carry out effective cleaning work.

FIG. 4 and FIG. 5 illustrate the time required for cleaning the first conduit 74 and the second conduit 82 by the cleaning method according to the prior art and the cleaning method according to the present invention.

That is, a conventional cleaning method is shown in FIG. By supplying into the conduit 74, the first conduit 74
Cleaning work is being carried out inside. In this case, the conventional method
It takes approximately 30 seconds to clean the first conduit 74, and the amount of thinner used is 710 cc.

On the other hand, in the method according to the present invention shown in Figure 4, the compressed air is 5 kg/cd and the thinner pressure is 5.5 kg/cd.
As can be easily understood from the figure, the cleaning time is about 20 seconds and the amount of thinner used is 200 cc, which is a significant reduction in the cleaning time and amount of thinner used compared to the conventional method.

That is, in the conventional method, after the paint adhering to the inside of the first pipe line 74 is dissolved with thinner, the dissolved paint is led out to the outside via compressed air. However, in the method of the present invention, the thinner and compressed air are mixed and the first pipe line 74 is
By supplying the fluid into the mixed fluid, bubbles are formed in the mixed fluid, and the impact force generated when the bubbles are destroyed causes the first pipe line 7 to
It becomes possible to effectively remove the paint inside 4. Therefore, cleaning work can be carried out in a short time, especially when a large number of painting guns 52 are used as in the painting apparatus 12 shown in this embodiment.
For those having sizes a to 52d and 60a to 60d, the cleaning work can be shortened at once, and the amount of thinner used in the cleaning work can be reduced as much as possible, making it extremely economical. The effect of being a target can be obtained.

Next, FIGS. 5a and 5b illustrate the results of cleaning the second conduit 82 using the conventional method and the method of the present invention. In addition, in the conventional method, compressed air is 5 kg/cI+! , the pressure of the thinner is 5 kg/-, and in the method of the present invention, the compressed air is 5 kg/cJ1 and the pressure of the thinner is 5.5 kg/-.
− is selected.

In this case, as in the case of cleaning the first pipe line 74, the conventional method requires 7 seconds to clean and the amount of thinner used is 86 c.
However, in the method of the present invention, the cleaning time is 3 seconds and the amount of thinner used is 20 cc, which shows that the cleaning time and amount of thinner used are significantly reduced.

As described above, according to the present invention, when cleaning a pipe line for supplying a predetermined paint to a painting gun, compressed air is first continuously supplied into the pipe line, and then a predetermined paint is supplied to the paint gun. The compressed air and a solvent such as thinner are passed through the pipe for a certain amount of time to clean the pipe. Therefore, the mixed fluid having air bubbles passes through the pipe, and the air bubbles collide with and destroy the paint remaining in the pipe, and the impact force causes the paint to be easily and reliably removed. It can be dissolved and removed from the pipe and discharged to the outside. Therefore, compared to the conventional method, the time required for cleaning the inside of the pipe and the amount of solvent used, such as thinner, are reduced at once, and the cleaning process can be carried out effectively. In particular, for painting equipment that has a large number of painting guns, it is possible to significantly shorten the time spent on cleaning operations and to achieve an extremely economical cleaning process by reducing the amount of solvent used as much as possible. I can do it.

As a result, the effect that the entire painting work process can be carried out efficiently is obtained.

Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to these embodiments, and various improvements and changes in design can be made without departing from the gist of the present invention. Of course.

[Brief explanation of the drawing]

Fig. 1 is a schematic configuration diagram of a coating line system incorporating a coating device for carrying out the cleaning method according to the present invention, Fig. 2 is a side view of the coating device shown in Fig. 1, and Fig. 3 is a schematic diagram of a coating line system according to the present invention. 4 and 5 are explanatory diagrams showing the relationship between the injection time of thinner and compressed air in the conventional cleaning method and the cleaning method of the present invention. 10... Painting line 12... Painting device 14
... Vehicle body 36 ... Upper painting mechanism 38
．． 40... Side painting mechanisms 52a to 52d, 60a to 60d-.
- Paint gun 62...Paint exchange means 74...Pipe line 78.80...Pulp 82...Pipe line 02
12 20 Time (seconds) 0 2
345 7 hours (seconds) 0123 hours (
seconds)

Claims (3)

[Claims] (1) A cleaning method for cleaning the inside of a pipe connected to a paint gun constituting a painting device for supplying a predetermined paint to the paint gun, the method first introducing compressed air into the pipe. Then, while the compressed air is being supplied, a cleaning solvent is passed through the pipe for a predetermined period of time, and the inside of the pipe is cleaned through the mixed fluid of the solvent and the compressed air. How to clean painting equipment. (2) In the method according to claim 1, compressed air and a solvent are introduced into a pipe line for supplying paint to a painting gun under the switching action of a valve mechanism, and the pressure of the solvent is A method of cleaning painting equipment using a pressure greater than that of compressed air. (3) In the method according to claim 1 or 2, a cleaning solvent mixed with the compressed air is passed through the compressed air, bubbles are generated in the cleaning solvent, and the bubbles are ruptured. A method for cleaning painting equipment consisting of cleaning the interior of the pipeline under the action of impact.