JPH04260463A - Color changing apparatus of automatic painting machine - Google Patents

Abstract

PURPOSE:To reduce the loss of paint at the time of a color change, in a color changing apparatus for painting a car, by constituting a metering valve of the first valve connected to a color change box through a flow rate sensor, the second valve connected to a pressure air supply means and the third valve connected to a spray gun. CONSTITUTION:The paint of the color selected by a color change box 6 is supplied to a metering valve 13 through a first painting hose 11 and passes through a manifold 18 to enter a third valve 17 from a first valve 14 to be sprayed to a car body by a spray gun 2. At the time of a color change, a second valve 16 is opened and pressure air is sent to the first valve 14 through a hose 15 and the second valve 16 to be sent in the painting hose 11. By this constitution, the paint in the painting hose 11 is returned to a paint box through the color change box 6 and circuation. When a flow rate sensor 19 detects the absence of the residual paint in the painting hose 11, the supply of pressure air is stopped and paint of a new color is supplied.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color changing device for an automatic paint coating machine used, for example, in a painting line for car bodies such as automobiles.

0002

2. Description of the Related Art Generally, in a painting line for painting the bodies of automobiles, etc., in order to improve efficiency, reduce manpower, and ensure uniformity of painting, the inside of a painting booth 1, where vehicle bodies are transported, as shown in FIG. An automatic painting machine is used in which a painting robot 3 equipped with a spray gun 2 for spraying paint is installed, and the painting robot 2 paints the car body with the spray gun 2 in place of the operator.

By the way, in the automatic painting machine described above, if the paint color of the car body being conveyed into the paint booth 1 changes, the paint of the color corresponding to the car body must be sprayed by the spray gun 2. A color changing device for changing the color of the paint sprayed from the spray gun 2 is provided in the middle of the paint path leading to the spray gun 2.

FIG. 5 shows an example of the above-mentioned color changing device for the automatic painting machine, and 4 is a paint storage located outside the painting booth 1, which includes a plurality of paint tanks each storing a plurality of colors of paint. 5. Reference numeral 6 denotes a color change valve box arranged in the paint booth 1, in which a plurality of color change valves 8 connected to each paint tank 5 of the paint storage 4 via a circulation 7 are connected to a manifold 9.
By selecting one of the plurality of color change valves 8 and closing the others, a desired color of paint is selected from each paint tank 5 in the paint storage 4 and the color change valve 8 is connected to the manifold. Supply to 9. 10 is a metering valve installed in the painting robot 3, the inlet side is connected to the manifold 9 of the color change valve box 6 via the first paint hose 11, and the outlet side is connected to the spray gun 2 via the paint hose 12. The paint is supplied from the color change valve box 6 to the spray gun 2 or stopped.

[0005] In the color changing device for the automatic coating machine,
The color paint selected from each paint tank 5 of the paint storage 4 by each color change valve 8 of the color change valve box 6 is set to a predetermined injection pressure via the circulation 7, and then sent to the color change valve box 6. The paint is supplied to the manifold 9, from which it is sprayed toward the vehicle body by the spray gun 2 via the first paint hose 11, the metering valve 10, and the second paint hose 12.

[0006]

[Problems to be Solved by the Invention] By the way, in the above-mentioned color changing device for an automatic painting machine, when changing the color of the paint sprayed from the spray gun 2, it is necessary to change the color of the paint between the color change valve box 6 and the spray gun 2. hose 11,
The paint remaining in the metering valve 10 and the second paint hose 12 must be discarded and cleaned, and then new paint must be supplied to the spray gun 2. However,
If the paint remaining in the paint hose 11, metering valve 10, and second paint hose 12 between the color change valve box 6 and the spray gun 2 is to be discarded every time a color change is performed, the paint will be removed from the paint line. There was a problem that the amount used increased significantly and the painting cost became high. Also,
As the amount of paint used on the painting line increased, the painting booth and booth circulation pit became increasingly dirty, leading to increased maintenance costs.

SUMMARY OF THE INVENTION Therefore, in view of the above-mentioned problems of the conventional apparatus, it is an object of the present invention to provide a color changing apparatus for an automatic painting machine that reduces paint loss when changing colors and reduces painting costs. .

[0008]

[Means for Solving the Problems] As a means for achieving the above object, the present invention provides a color change valve that selects and supplies paint of a color according to specifications from a paint storage storing paints of a plurality of colors. An automatic painting machine including a color change valve box, a metering valve connected to the color change valve box via a first painting hose, and a spray gun connected to the metering valve and a second painting hose. In the color change device, the metering valve is connected to the color change valve box via the first painting hose, the second valve is connected to the pressurized air supply means, and the second valve is connected to the color change valve box through the first painting hose. A third valve is connected to the spray gun through a painting hose, and a flow rate sensor is installed in the first painting hose to detect the presence or absence of paint in the hose. be.

[0009]

[Operation] According to the above means, during painting, the first and third valves of the metering valve are opened, and the paint of the color selected and supplied by the color change valve box is supplied.
The liquid is supplied to the spray gun via the first painting hose, the first and third metering valves, and the second painting hose, and is sprayed onto the object to be painted from this spray gun. Also, when changing colors, the first and second valves of the metering valve are opened, and pressurized air is supplied to the first painting hose via the metering valve.
The paint in the paint hose is returned to the paint storage. When there is no paint left in the first painting hose, the flow rate sensor detects it, and based on the detection signal, the second valve is closed to stop the supply of pressurized air, and the remaining paint remains in the second painting hose. After discarding the existing paint and cleaning it, supply new paint to the spray gun.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a color changing device for an automatic coating machine according to the present invention will be described below with reference to FIGS. 1 to 3. Furthermore, Figure 5
Components that are the same as those of the conventional device shown in FIG.

In FIGS. 1 to 3, reference numeral 13 denotes a triple metering valve installed in the painting robot, which is connected to the color change valve box 6 through the first painting hose 11.
a first valve 14 connected to a manifold 9, and a second valve 1 connected to a pressure air supply means (not shown), such as an air pump, via an air hose 15.
6 and a third valve 17 connected to the spray gun 2 via a second painting hose 12 are combined through a manifold 18, and the first valve 14 and the third valve 17 are opened during painting. Furthermore, the first valve 14 and the second valve 16 are configured to open when changing colors. 19 is a flow rate sensor installed near the color change valve box 6 of the first painting hose 11;
The presence or absence of paint in the first painting hose 11 is detected, and when it is detected that there is no paint in the first painting hose 11, the second valve 16 of the metering valve 13 is closed by a signal.

In the above embodiment, the paint color selected by the color change valve box 6 at the time of painting is
It is supplied to the metering valve 13 via the first painting hose 11, and at this metering valve 13, as shown in FIG. from the third valve 17 to the second
The paint is sprayed onto the vehicle body by the spray gun 2 through the paint hose 12.

Next, when changing the color of the paint sprayed from the spray gun 2, the second
The third valve 16 is opened (at this time, the third valve 17 is closed), and the pressure air from the pressure air supply device is supplied to the metering valve 13 via the air hose 15. As shown in 3,
The water passes from the second valve 16 through the manifold 18 to the first valve 14, and is supplied from the first valve 14 to the first painting hose 11. In this way, when pressurized air is supplied from the metering valve 13 to the first painting hose 11, the paint inside the first painting hose 11 is changed by the pressure air through the color change valve box 6 and the circulation 7. It is returned to the warehouse 5. Then, after the flow rate sensor 19 detects that there is no paint left in the first painting hose 11 and the detection signal closes the second valve 16 of the metering valve 13 to stop the supply of pressurized air, After the paint remaining in the second painting hose 12 is discarded and cleaned, new paint is supplied to the spray gun 2. In this case, unlike the conventional method where the paint between the color change valve box 6 and the spray gun 2 is discarded, the paint between the metering valve 13 and the spray gun 2 is only discarded, so the color change is more efficient than the conventional system. There is less paint loss during cleaning.

[0014]

[Effects of the Invention] According to the present invention, as explained above, it is only necessary to discard the paint between the metering valve and the spray gun when changing colors, so the amount of paint used on the painting line can be reduced. This reduces painting costs, reduces dirt in the painting booth and booth circulation pit, and reduces maintenance costs.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of main parts showing a color changing device for an automatic coating machine according to the present invention.

FIG. 2 is an explanatory diagram showing the metering valve used in the present invention during painting.

FIG. 3 is an explanatory diagram showing the color change of the metering valve used in the present invention.

FIG. 4 is a schematic diagram showing an automatic coating machine.

FIG. 5 is a configuration diagram showing a conventional color changing device for an automatic coating machine.

[Explanation of symbols]

2 Spray gun 3 Painting robot 4 Paint storage 6 Color change valve box 7 Circulation 11 First painting hose 12 Second painting hose 13 Metering valve 14 First valve 16 Second valve 17 Third valve 19 Flow rate sensor

Claims (1)

[Claims] Claim 1: A color change valve box that selects and supplies paint of a color according to specifications from a paint storage in which paints of a plurality of colors are stored, and the color change valve box is connected via a first paint hose. In the color changing device for an automatic paint coating machine, the metering valve is connected to the first painting hose. a first valve connected to said color change valve box through said color change valve box, a second valve connected to said pressurized air supply means, and a third valve connected to said spray gun through said second painting hose. A color changing device for an automatic coating machine, characterized in that the first coating hose is provided with a flow rate sensor for detecting the presence or absence of paint in the first coating hose.