JPH0248068A - Method and device for painting - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a coating method and a coating apparatus that selectively perform coating with water-based paint and coating with solvent paint using a common coating head.

(Prior art) Conventionally, a common coating head was used to selectively paint with multiple colors of paint, and when changing colors, cleaning was performed by introducing a cleaning liquid into a communication path connected to the coating head. A color change coating device that performs painting using multiple colors of paint is known (Japanese Patent Application Laid-open No. 53-99206, Japanese Utility Model Application Publication No. 58-58870). Paints were limited to multiple colors using the same solvent, and there was no particular method for painting using water-based paints and solvent paints using different solvents.

(Problem to be Solved by the Invention) By the way, in order to perform painting using a water-based paint and a solvent paint using one painting device, a common application head is used and a communication path connected to the water-based paint and a solvent paint is connected to the common application head. It is conceivable to introduce selectively, but in such a case, the problem is how to clean the communication passage when switching between water-based paint and solvent paint, or how to shorten the cleaning time.

The present invention solves these problems and provides a coating method and a coating device that make it possible to perform coating using water-based paint and solvent paint with one coating device, and shorten the cleaning work time. Its purpose is to provide.

(Means for Solving the Problem) In order to achieve the above object, the invention as claimed in claim] provides a coating method in which coating with water-based paint and coating with solvent paint are selectively performed using a common coating head. When switching from painting with water-based paint to painting with solvent paint, cleaning liquid is introduced in the order of water, hydrophilic solvent, and solvent into the communication path connected to the coating head, and the process changes from painting with solvent paint to painting with water-based paint. In the invention according to claim 2, wherein when switching to painting, cleaning is performed by introducing a cleaning liquid into the communicating path in the order of a solvent, a hydrophilic solvent, and water. A coating device selectively performs coating with a water-based paint and coating with a solvent paint, wherein a first manifold is connected to an upstream end of a communicating path connected to the coating head, a supply path is connected to the first manifold, A second manifold that selectively connects the water-based paint introduction pipe and the solvent paint introduction pipe is connected to the upstream end of the supply passage through a selection valve, and the supply passage is connected between the first manifold and the supply passage. A switching valve is provided to switchably connect the water to the communication path side and the drain side, and water is supplied to the first manifold and the second manifold through a first cleaning valve and a second cleaning valve, respectively. In the invention of claim 3, characterized in that the piping, the hydrophilic solvent piping, and the solvent piping are selectively connected, a common application head is used to select painting with water-based paint and painting with solvent paint. A first manifold is connected to the upstream end of a communicating path connected to the coating head, a pair of supply passages are connected to the first manifold, and a selection valve is provided at the upstream end of one of the supply passages. A third manifold connects a water-based paint inlet pipe through a third manifold, and a fourth manifold connects a solvent paint inlet pipe to the upstream end of the other supply passage through a selection valve, and connects the first manifold and each of the supplies. A switching valve is interposed between the passage and the supply passage to switchably connect each supply passage to a communication passage side and a drain side, and a water piping and a hydrophilic solvent piping are connected to the first manifold via a first cleaning valve. and a solvent pipe, a water pipe is connected to the third manifold via a third wash valve, and a solvent pipe is connected to the fourth manifold via a fourth wash valve. do.

(Function) A case will be described in which the method of claim 1 is implemented with the apparatus of claim 2.

The water-based paint or solvent paint introduced into the second manifold from either the water-based paint introduction pipe or the solvent paint introduction pipe by opening the selection valve is applied to the object to be coated from the application head via the supply passage, the first manifold, and the communication passage. Then do the painting work. At this time, when switching from painting using water-based paint to painting using solvent paint, close the selection valve, switch the switching valve to the drain side, open the second cleaning valve, and pour cleaning liquid into the supply passage.
The supply passage is cleaned by introducing a hydrophilic solvent and a solvent in that order, and the first cleaning valve is opened to supply water, water, and a cleaning liquid to the communication passage.
The communication path is cleaned by introducing a hydrophilic solvent and a solvent in that order.

In this way, by introducing a hydrophilic solvent that exhibits affinity for both water and solvent between water and solvent, which have no affinity for each other, water droplets remaining in the passage are dissolved into the hydrophilic solvent. The water droplets of the hydrophilic solvent are swept away by the solvent, and when painting with a solvent paint, the water droplets remaining in the passage do not mix with the solvent paint and cause coating defects. Conversely, when switching from painting using a solvent paint to painting using a water-based paint, cleaning is performed by introducing a cleaning liquid into the supply passage and the communication passage in the order of solvent, hydrophilic solvent, and water. According to the method, when applying a water-based paint, the solvent remaining in the passage does not mix with the water-based paint.

On the other hand, according to the apparatus of the second aspect, cleaning can be performed separately in the supply passage and the communication passage, thereby speeding up the cleaning operation.

In addition, in the apparatus of claim 3, when switching from painting with water-based paint to painting with solvent paint, the third cleaning valve is opened to introduce water into the one supply passage, and the first
The cleaning valve is opened and the cleaning liquid is introduced into the communication passage in the order of water, hydrophilic solvent, and solvent, and in the reverse case, the fourth cleaning valve is opened and the solvent is introduced into the other supply passage, and the first cleaning The valve is opened and the cleaning liquid is introduced into the communication passage in the order of solvent, hydrophilic solvent, and water. In this case, the first cleaning starts when the communication passage has been cleaned without waiting for the supply passage to be cleaned. The valve can be closed and the switching valve on the paint side to be used next can be switched to the communication path side to introduce paint and move on to painting work, which further speeds up the cleaning work.
The supply passage side, which has a relatively long route, can be cleaned with water or a solvent without using a hydrophilic solvent, and only the communication passage side, which has a relatively short route, needs to be cleaned with a hydrophilic solvent, and the hydrophilicity required for cleaning is It is possible to reduce running costs by minimizing the amount of solvent consumed.

(Example) Referring to FIG. 1, reference numeral 1 indicates a coating head for applying paint to an object to be coated, a communication path 2 is connected to the coating head 1, and a communication path 2 is connected to the upstream end of the communication path 2. A second manifold 5 is connected to the first manifold 3 via a supply pipe 4, and a plurality of water-based paint introduction pipes 6 and a plurality of solvent paint introduction pipes are connected to the second manifold 5. 7, water-based paints and solvent paints are selectively introduced, and color change coating can be performed using water-based paints or solvent paints as appropriate.

To explain this in detail, the first manifold 3 includes a supply passage 4
a switching valve 9 which is switchably connected to a passage 3a in the manifold 3 which is connected to the communication passage 2 and a drain passage 8 which is connected to the outside;
was installed, and cleaning piping consisting of an air piping 10, a water piping 11, a hydrophilic solvent piping 12, and a solvent piping 13 was connected to the passage 3a via a first cleaning valve 14. The first cleaning valve 14 is an air valve 14 attached to the first manifold 3.
a1 solvent valve 14b, an on-off valve 14c, and a water valve 14f and a hydrophilic solvent valve 14 attached to a cleaning valve manifold 14e connected to the on-off valve 14c via a cleaning liquid pipe 14d.
g, and during painting work, the first cleaning valve 14 is closed and the switching valve 9 is switched to the passage 3a side to transfer the paint to the passage 3a.
During cleaning work, the switching valve 9 is switched to the drain passage 8 side to guide the cleaning liquid to be introduced into the supply piping 4 as described later into the drain passage 8, and each valve of the first cleaning valve I4 is 14a, 14b, 14r, 14g
The communication passage 2 is cleaned by sequentially opening the passages.

The second manifold 5 includes a passage 5a in the second manifold 5 that connects each paint introduction pipe 6.7 to the supply passage 4, and a return pipe Ba, ? A plurality of selection valves 15 switchably connected to the passage 5a were attached, and a cleaning pipe similar to the above was connected to the passage 5a via a second cleaning valve 16. The second cleaning valve 16 is an air valve 1 attached to the second manifold 5.
6a Solvent valve 16b and on/off valve 16C1 and cleaning liquid pipe 1
A water valve 16r and a hydrophilic solvent valve 11 are attached to the cleaning valve manifold 1.6e, which is connected to the on-off valve 16c via 8d.
3g, and during painting work, one selection valve 15 corresponding to a predetermined color of water-based paint or solvent paint is switched to the passage 5a side, and the paint is guided to the supply passage 4 through the passage 5a. During cleaning work, the selection valve 15 is switched to the return pipe Ba, 7a side to return the paint to the supply source side, and each valve 16a, 5lf3b, of the second cleaning valve 16,
18f' and 516g are sequentially opened to clean the supply passage 4.

In addition, 17 in the figure is the drain passage 8 that guides the cleaning liquid to the outside.
The figure shows the drain on-off valve installed.

Painting work and cleaning work will be explained based on the above embodiments.

The first selection valve 15 is switched to the passage 5a side to introduce a predetermined paint into the second manifold 5, and the supply passage 4, the switching valve 9, and the first
Coating is applied from the coating head 1 to the object to be coated via the manifold 3 and communication path 2. When this painting work is completed, the selection valve 15 is switched to the return pipe Ba, 7a side, and the air valve 16a of the second cleaning valve 16 is opened to introduce air into the supply passage 4 to remove residual paint in the supply passage 4. Applying head 1
When the upstream end of the residual paint passes through the switching valve 9, the switching valve 9 is switched to the drain passage 8 side, and at the same time, air is introduced from the first cleaning valve 14 into the communication passage 2 to continue. The residual paint is pushed out from the coating head 1. Next, in order to follow this extrusion operation, the drain on-off valve 1 is
7 is opened and each cleaning liquid is passed through the supply passage 4 and the communication passage 2 by the first cleaning valve 14 and the second cleaning valve 16, respectively, but it is necessary to switch from painting work or color change painting from water-based paint to solvent paint. In this case, each water valve 14f1 of the first cleaning valve 14 and the second cleaning valve I6, each hydrophilic solvent valve 14g, and each solvent valve 14
b are sequentially opened and the cleaning liquid is introduced into the supply passage 4 and the communication passage 2 in the order of water, hydrophilic solvent, and solvent, and conversely, when switching from solvent paint to color change painting with water-based paint,
The supply passage 4 and the communication passage 2 are cleaned by introducing a cleaning liquid into the supply passage 4 and the communication passage 2 in the order of a solvent, a hydrophilic solvent, and water, respectively. In this way, between cleaning with water and cleaning with a solvent, cleaning with a hydrophilic solvent that has an affinity for both is performed, thereby indirectly making the water and solvent, which have no affinity for each other, compatible and preventing cleaning failures. Furthermore, in the case of color changing painting between water-based paints or color changing painting between solvent paints, cleaning is performed by introducing only water and a solvent into the supply passage 4 and the communication passage 2, respectively. Note that when thinner is used as the solvent, an ammonia aqueous solution is used as the hydrophilic solvent.

Next, another embodiment will be described based on FIG. 2.

In this embodiment, a pair of supply pipes 4 are connected to the first manifold 3 connected to the coating head 1 via the communication path 2 in parallel.
．． A third manifold 18 connecting a plurality of water-based paint introduction pipes 7 is connected to the upstream end of one supply pipe 4, and a plurality of solvent paint introduction pipes is connected to the upstream end of the other supply pipe 4. 8 is connected to the fourth manifold 19, and the water-based paint from the third manifold 18 side and the solvent paint from the fourth manifold 19 side are selectively introduced into the first manifold 3. Color change painting is done using solvent paint.

To explain this in detail, a pair of switching valves 9.9 are attached to the first manifold 3, which switchably connect each supply passage 4 to the passage 3a in the first manifold 3 and the drain passage 8. Furthermore, an air pipe 10, a water pipe 11, a hydrophilic solvent 12, and a solvent pipe I3 are connected to the passage 3a through a first cleaning valve 14 configured in exactly the same manner as in the previous embodiment.

The third manifold 18 includes a plurality of selection valves 15 that switchably connect each water-based paint introduction pipe 6 to a passage 18a in the third manifold 18 connected to the supply passage 4 and a return pipe 6a.
is attached to the third manifold 1 in the passage 18a.
The air pipe 10 and the water pipe 11 are connected through a third cleaning valve 20 consisting of an air valve 20a and a water valve 20b attached to 8, and during painting work, the selection valve 15 of 1 is placed on the passage 18a side. During the cleaning operation, the six valves 20a and 20b of the third cleaning valve 20 are sequentially opened to clean the supply passage 4.

Similarly to the above, the fourth manifold 19 includes a plurality of selection valves 1 that switchably connect each solvent paint introduction pipe 7 to the passage 19a in the fourth manifold 19 and the return pipe 7a.
5 is installed, and the air pipe 10 and the solvent pipe 1 are connected to the passage 19a through a fourth cleaning valve 21 consisting of an air valve 21a and a solvent valve 21b installed in the fourth manifold 19.
3, and the selection valve 15 is connected during painting work.
A solvent paint of a predetermined color is introduced into the supply passage 4 through the supply passage 4, and during cleaning work, the six valves 2+a and 21b of the fourth cleaning valve are sequentially opened to clean the supply passage 4.

Painting work and cleaning work will be explained based on the above embodiments.

When painting with water-based paint, use the third manifold! The selection valve 15 on any one of the 8 sides is switched to the main passage 18a side, and a predetermined paint is guided to the third manifold 18, and then passed through the supply passage 4, the switching valve 9, the first manifold 3, and the communication passage 2 to the coating head 1. When applying solvent paint to the object to be coated, in the same way, select valve 15 on the fourth manifold 19 side is switched to the main passage 19a side to guide the paint to the fourth manifold 19, The coating is applied from the coating head 1 to the object to be coated. When switching from water-based paint to solvent paint, after performing the same extrusion work with air as in the previous embodiment, water is introduced into the supply passage 4 by the third cleaning valve 20, and at the same time, the first cleaning valve 14, the cleaning liquid is introduced into the communication passage 2 in the order of water, a hydrophilic solvent, and a solvent. Conversely, when switching from solvent paint to water-based paint, the fourth cleaning valve 21 introduces the cleaning liquid into the supply passage 2 in the same manner as described above. At the same time, the first cleaning valve 14 introduces the cleaning liquid into the communication passage 2 in the order of solvent, hydrophilic solvent, and water to clean the supply passage 4 and the communication passage 2, and the communication passage 2 is cleaned. Once this is completed, painting with the next paint is started, and cleaning of the supply passage 4 is completed during this painting. In addition, in the case of color changing painting between water-based paints or color changing painting between solvent paints, only water or solvent is introduced by the first cleaning valve 14 even when cleaning the communicating path 2 side.

(Effects of the Invention) As described above, according to the invention of claim 1, cleaning with water and cleaning with a solvent have an affinity for both in the communication path connected to a common coating head during cleaning work. By adding cleaning with a hydrophilic solvent, cleaning liquid that has no affinity for the paint to be used next can be reliably discharged from the communication path, preventing paint defects due to poor cleaning, and reducing the need for one painting device. It has the effect of enabling painting with water-based paints and solvent paints.

Further, according to the invention of claim 2, the communication passage and the supply passage can be washed separately and in parallel, thereby reducing the cleaning time.Furthermore, according to the invention of claim 3, Painting work and supply passage cleaning work can be performed in parallel, making it possible to shorten layer cleaning time and reduce the amount of hydrophilic solvent consumed, further improving productivity. have

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing one embodiment of the present invention, and FIG. 2 is a circuit diagram of another embodiment. 1... Application head 2... Communication path 3... First manifold 4... Supply path 5... Second manifold 6... Water-based paint introduction pipe 7... Solvent paint introduction Pipe 8...Drain passage 9...Switching valve 11...Water piping 12...Hydrophilic solvent piping 13...Solvent piping 14...First cleaning valve 15...Selection Valve 16...Second cleaning valve 18...Third manifold 19...Fourth manifold 20...Third cleaning valve 21...Fourth cleaning valve section C1 branch λ'

Claims (1)

[Claims] 1. A coating method that selectively performs coating with water-based paint and coating with solvent paint using a common coating head, comprising:
When switching from painting with water-based paint to painting with solvent paint, water,
When switching from painting with a solvent paint to painting with a water-based paint, it is recommended to introduce the cleaning liquid into the communication path in the order of the solvent, the hydrophilic solvent, and water for cleaning. Characteristic painting method. 2. A coating device that selectively performs coating with water-based paint and coating with solvent paint using a common coating head,
A first manifold is connected to the upstream end of the communication path connected to the coating head, a supply path is connected to the first manifold, and a water-based paint inlet pipe and a solvent paint inlet pipe are connected to the upstream end of the supply path via a selection valve. A second manifold that selectively connects is connected, and a switching valve is interposed between the first manifold and the supply passage to switchably connect the supply passage to the communication passage side and the drain side, A coating characterized in that water piping, hydrophilic solvent piping, and solvent piping are selectively connected to the first manifold and the second manifold via a first cleaning valve and a second cleaning valve, respectively. Device. 3. A coating device that selectively performs coating with water-based paint and coating with solvent paint using a common coating head,
A first manifold is connected to the upstream end of the communication path connected to the application head, a pair of supply paths are connected to the first manifold,
A third manifold connects a water-based paint introduction pipe to the upstream end of one supply passage via a selection valve, and a fourth manifold connects a solvent paint introduction pipe to the upstream end of the other supply passage via a selection valve. A switching valve is provided between the first manifold and each of the supply passages to connect each of the supply passages to a communication passage side and a drain side, and a first cleaning valve is provided to the first manifold. selectively connecting the water piping, the hydrophilic solvent piping, and the solvent piping via valves, connecting the water piping to the third manifold via a third cleaning valve, and connecting the fourth cleaning valve to the fourth manifold. A coating device characterized in that a solvent piping is connected through a solvent pipe.