JPS642432B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paint color changing method and apparatus used for selecting a desired paint from among a plurality of paints and supplying the selected paint to a spray gun.

A conventional method and apparatus for changing the color of paint will be described with reference to FIG. 1, taking as an example a case in which two types of paint, color A and color B, are to be used.

The inlet side opening of a valve unit 4, which has an on-off valve 3 which is opened and closed by an air cylinder or the like (not shown) interposed in the inlet side flow path of a valve case 2 having a T-shaped flow path 1, is connected to a thinner pressure feeding conduit 5, respectively. It is connected to the A color paint pressure feed pipe line 6 and the B color paint pressure feed pipe line 7, and the outlet side branch flow paths of each valve unit 4 are connected in series to form a series flow path 8, thereby forming a valve assembly 10. On the other hand, a high-pressure air pipe 15 and a low-pressure air pipe 16 extending from a high-pressure air source 11 and a low-pressure air source 12 through automatic on-off valves 13 and 14 respectively are connected to a ball valve 1.
7 to collect in the collecting pipe 18.
The terminal opening of the valve assembly 10 is connected to the serial flow path 8 of the valve assembly 10.
The color changing unit 20 is constructed as a whole. One end of a paint hose 19 is connected to the outlet opening 8a of the color change unit 20, and a regulator 9 and an auto spray gun 21 are attached to the other end in this order. In FIG. 1, 22 is a thinner source.

Therefore, in order to change the color from A color paint to B color paint, the on-off valve 3A of the A-color paint valve unit 4 is closed, and the automatic on-off valve 14 is opened, and the low-pressure air pumped from the low-pressure air source 12 is used to The A color paint present in the flow path from the serial flow path 8 of the valve assembly 10 to the auto spray gun 21 via the paint hose 19 is injected from the auto spray gun 21 to complete so-called extrusion painting, and then the automatic opening/closing valve is Almost at the same time as closing 14, the thinner valve 3T
Then, at the same time as closing the thinner valve 3T, the automatic opening/closing valve 13 is opened to remove the A color paint remaining in the flow path. The thinner present in the passage is blown with air, and after repeating such thinner washing and air blowing several cycles, the valve 3B of the valve unit 4 for B color paint is opened to transfer the B color paint from the serial flow passage 8 to the paint hose 19. After completing this color change operation, the auto spray gun 2 is filled with water.
The needle valve No. 1 was opened and B color paint was sprayed using a conventional method.

Then, the color changing method and color changing unit 2 described above
0, the time required for the color change operation is determined by the length of the paint hose 19 extending from the outlet side opening 8a of the color change unit 20 to the auto spray gun 21. It is necessary to shorten the length of the paint hose 19 as much as possible by installing it near the paint hose 19.

Incidentally, in recent years, when painting has been carried out by attaching an auto spray gun 21 to the wrist of an industrial robot, a problem has arisen in that it is difficult to shorten the color change time.

In other words, the movable range of the robot arm is considerably larger than the stroke of a conventional reciprocator, and moreover, it is possible to move the robot arm itself from the front to the center side of a positioned vehicle body by placing it on a transfer device. On the other hand, due to the layout of control wiring and input piping for paint, etc. to the color changing unit, the color changing unit 20 is either fixed near the robot body or placed on the robot body. As a result, the length of the paint hose 19 becomes long, resulting in the above-mentioned problem.

The present invention has been made in view of the above points, and its purpose is to solve the above-mentioned problems and shorten the color change time. The gist is that, in addition to the main paint pumping path leading from the color change unit to the spray gun, a paint pumping path is used, which includes a sub-pressing path that branches off from the main pumping path and is connected to the main pumping path near the spray gun. When painting the current color by supplying the current color paint to the spray gun through the main pressure feed path, first fill the auxiliary pressure feed path with the color paint, and then supply pressurized air to the main pressure feed path to apply the current color. The color paint on the main pressure feed path is extruded to the front of the connection part, the color extrusion coating is applied to the main pressure feed path, and immediately after this extrusion is completed, the front part is closed, and almost at the same time as this closing, the sub-color paint is extruded. Pressurized air is sent into the pressure feeding path to extrude the color paint filled in the auxiliary pressure feeding path, and the color paint is supplied to the spray gun, thereby transferring the color extrusion coating applied to the auxiliary pressure feeding path to the main pressure feeding path. The color changing unit feeds thinner and air to the main pressure feed path almost simultaneously with the current color extrusion painting applied to this sub-pressure feed path, and the path to the closing portion is Immediately after cleaning, the route from the color change unit to the closed part of the main pressure feed path is filled with the next color paint, and after the completion of extrusion painting of the current color applied to the sub pressure feed path, the paint is sprayed from the sub pressure feed path. Deliver thinner and air to the path leading to the tip of the gun to clean it.
Next, the front portion of the connecting portion is opened to force-feed the filled next color paint to the spray gun.

Further, the gist of the painting color changing device according to the second invention of the present application is that a first valve means located immediately after the color changing unit and the spray gun are connected to the main paint pressure feeding path connecting the color changing unit and the spray gun. and a second valve means located in front of the color changing unit, and a sub-pressure feeding path to which the developing color paint is supplied from the developing color paint valve in the color changing unit before the color change. is connected between the first valve means and the second valve means, and is provided in the main pressure feed path upstream of the second valve means. A discharge passage is provided between the third valve means and the first valve means for discharging cleaning air and thinner in the main pressure supply passage, and is connected to a thinner supply source and a pressurized air source, and is connected to the auxiliary pressure supply passage. A fourth valve means is provided in the first valve means for causing the paint supplied in the passage to flow out to the spray gun and for guiding cleaning air or thinner into the auxiliary pressure passage when cleaning the inside of the auxiliary pressure passage. It's all about connecting and becoming.

Hereinafter, an embodiment according to the present invention will be described based on FIG. 2. FIG. 2 is an overall explanatory diagram showing the paint color changing device.

Note that the same parts as in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted. First, to explain the configuration, the main pressure feed path 3 for the paint is formed by a pressure-resistant pipe that has one end connected to the outlet side opening 8a of the color change unit 20 and the other end connected to the paint receiving opening of the auto spray gun 21.
0, a sub-pressure feed path is branched from the main pressure feed path 30 near the color change unit 20 via a first valve means 31, and the sub-pressure feed path is connected to a second valve means 32.
It is connected to the main pressure feed path 30 near the spray gun 21 via.

The second valve means 32 includes a main passage 32A, which has one end connected to the sub-pressure passage 30 and the other end connected to the main pressure passage 30, and an air vent and paint having an open end branched from the main passage 32A, inside the valve case. A main valve 32P which is driven to open and close by an air diaphragm or the like is provided in the main flow path 32A, and an automatic opening/closing valve 32D for venting air and discharging paint is interposed in the main flow path 32E to form a discharge path 32E, thereby providing valve means as a whole. Configure.
Further, a third valve means 33 is provided upstream of the second valve means 32 in the main pressure feed path 30.

The third valve means 33 has a main pressure feed path 30 inside the valve case.
A flow path 33A is connected at one end to the main pressure feed path 30 and the other end is closed.
A flow path 33B connected to the second valve means side and an air/paint discharge path 33E are formed by branching from the vicinity of the closed portion of the flow path 33A and having the other end open. An automatic opening/closing valve 33P as a main valve and an automatic opening/closing valve 33D as a sub valve are interposed, respectively, to constitute a valve means as a whole. For the convenience of explaining the operation, the main pressure feed path 30 is defined as a flow path from the outlet side opening 8a of the color change unit 10 to the third valve means 33 and a flow path from the third valve means 33 to the gun tip of the auto spray gun 21. Distinguish between road and road.

Further, the terminal openings of the high pressure air pipe 23 and the low pressure air pipe 24 branched from the high pressure air pipe 15 and the low pressure air pipe 16, respectively, are connected to the inlet side openings 34I, 34I of a fourth valve means 34, which will be described later. One end of the pipe 40 is connected to the outlet side opening 340, and the other end is connected to the first valve means 31 immediately after the main valve 31M, that is, on the outflow side, via a check valve 36.

The fourth valve means 34 includes air passages 34A, 34A extending from the inlet side openings 34I, 34I and connected to both sides of the ball valve 34B in the valve case, and a main flow passage extending between the ball valve 34B and the outlet side opening 340. 34M and a thinner flow path 34T extending to the third inlet side opening 34I are formed, and an automatic valve 3 for opening and closing the air path is provided in each of the air flow paths 34A, 34A and the thinner flow path 34T.
4G, 34G, and an automatic opening/closing valve 34S for thinner are interposed to form a valve means as a whole. Further, the third inlet side opening 34I of the fourth valve means 34 and the thinner pressure feeding pipe 5 are communicated by a thinner pipe line 39.

An outlet portion of the main valve 33P of the third valve means 33 branched from the high pressure air pipe 23, that is, the main valve 33
A high-pressure air conduit 50 is provided immediately after P and connected via a check valve 37, and an automatic on-off valve 51 is interposed in the conduit 50 from the high-pressure air source 11. A pipe line 60 for pumping thinner is provided which branches from the pipe line 50 near the third valve means 33 via the fifth valve means 35 and reaches the thinner source 22.

Next, the operation of the paint color changing device having the above-mentioned configuration and an embodiment of the color changing method according to the present invention will be described with reference to FIG. 2 mentioned above.

Filling process of the current color (hereinafter referred to as A color) paint into the auxiliary pressure feed path: First, during the A color painting, that is, the A color paint is poured into the color change unit 20 while the on-off valve 3A of the color change unit 20 is opened. 20 is being supplied to the auto spray gun 21 via the main pressure feed path 30 and the main valve 33P of the third valve means 33 which is in the open state, open the on-off valve 31M of the first valve means 31, This fills the A color paint into the sub-pressure passage,
When this filling is completed, that is, after a predetermined period of time from the opening of the valve, for example, an electromagnetic pneumatic valve (not shown) is closed, and the application of air pressure is cut off by closing the pneumatic diaphragm of the first valve means 31 ( (not shown) to close the on-off valve 31M.

A color extrusion coating process for the flow path section of the main pressure feed path 30: Next to the above-mentioned A color paint filling process, almost at the same time as the on-off valve 3A for the A color paint of the color change unit 20 is closed, the color change unit is painted. 20 low pressure air pipes 1
By opening the automatic opening/closing valve 14 installed in 6 and introducing low-pressure air, the A color paint in the flow path is pushed out, thereby supplying the A color paint to the auto spray gun 21 and controlling the flow in the main pressure feed path 30. So-called A color extrusion painting will be applied to the road section. Then, low pressure air is introduced over almost the entire flow path in the main pressure feed path 30, and then the main valve 33P of the third valve means 33 is closed, and the automatic on-off valve 14 is also closed.

It is preferable to open the automatic low-pressure air valve 14 about one second before closing the valve 3A from the viewpoint of continuously supplying the A color paint to the spray gun.

A color extrusion painting process related to the auxiliary pressure feeding path; For example, one second before completion of the A color extrusion painting process in the main pressure feeding path, the main opening/closing valve 32P of the second valve means 32 is opened and the low pressure of the fourth valve means 34 is reduced. Open the automatic air valve 34G, thereby introducing low-pressure air (for example, 3.5 Kg/cm ² ) into the sub-pressure feeding path to push out the A color paint filled in the sub-pressure feeding path, and then press the auto spray gun 21. Supply A color paint to perform A color extrusion painting. Then, when the A color paint in the auxiliary pressure feeding path is pushed out to the flow path leading to the auto spray gun 21, that is, after a predetermined period, the automatic valve 34G of the fourth valve means is closed, thereby completing the process. .

A cleaning process for the flow path section of the main pressure feed path 30; almost simultaneously with the completion of the A color extrusion coating process for the flow path section, in other words, the color change unit 2
Immediately after closing the automatic valve 14 for low pressure air of 0 and the main valve 33P of the third valve means 33, the color change unit 20
At the same time, when the main valve 33P of the third valve means 33 is closed, the sub valve 33D is opened. As a result, A attached to the inner wall of the pipe in the flow path, etc.
Wash the colored paint with thinner, then use thinner valve 3.
At the same time as the T is closed, the automatic high-pressure air valve 13 of the color change unit 20 is opened for a short time to clean the inside of the flow path section with air. That is, the A color paint and air remaining in the flow path, the thinner introduced into the flow path in this process, and the high pressure air for air blowing are removed from the sub valve 33D of the third valve means 33 during thinner cleaning and air blowing. Exhausted from the system. Then, this thinner cleaning and air blowing are repeated several cycles during the period in which the A color extrusion coating process related to the auxiliary pressure passage is being carried out, and the cleaning process is carried out using the thinner valve 3T and the automatic valve 13.
Terminate by closing .

The next color (hereinafter B
Paint filling process (referred to as color): Immediately after the cleaning process for the flow path section is completed, the B color paint valve 3B of the color change unit 20 is opened to fill the B color paint into the flow path.

Cleaning step for the flow path section of the main pressure feed path 30; Immediately after the completion of the A color extrusion coating process for the auxiliary pressure feed path, while the main valve 33P of the third valve means 33 is closed, the thinner Fifth valve means 35
By alternately opening the automatic on-off valve 51 for high-pressure air one or more times, when the fifth valve means 35 is opened, the cleaning thinner is transferred from the thinner source 22 to the conduit 60 to the fifth valve means 35. When the on-off valve 51 is opened, high-pressure air is sent from the high-pressure air source 11 to the outlet portion of the main valve 33 of the third valve means 33 via the automatic on-off valve 51 and the conduit 50 to the main valve 33P. Reach the exit part. Therefore, the cleaning thinner and high-pressure air are injected from the gun tip (nozzle) of the auto spray gun 21 while alternately cleaning the A color paint remaining in the flow path. When the cleaning by injection is completed, the fifth valve means 35 and the automatic opening/closing valve 5 are opened.
1 and close the valve.

Filling the flow path section of the main pressure feed path 30 with B color paint; Immediately after completing the cleaning process for the flow path section, open the on-off valve 3B for the B color paint of the color change unit 20, and close the third valve. Since the main valve 33P of the second valve means 32 is opened, and since the main valve 32P of the second valve means 32 and the paint discharge needle valve of the auto spray gun 21 are in the closed state, the flow path of the main pressure feed path 30 is opened. The flow path is filled with B color paint.

B color spray painting: Once the B color paint is filled into the flow path section, the B color painting is started by opening the needle valve built into the auto spray gun 21 in a conventional manner. In this state, as is clear from viewing FIG. 2, the B color paint valve 3B of the color change unit 20 and the main valve 33P of the third valve means 33 are open, and the first valve means The main valve 31M of No. 31 and the main valve 32P of the second valve means 32 are closed, and when cleaning the auxiliary pressure passage in parallel with the B color spray painting, the thinner valve of the fourth valve means 34B is closed. The valve 34S and the high-pressure air valve 34G may be opened alternately once or multiple times. At this time, the sub-valve 32D of the third valve means 32 is opened to discharge the remaining A color paint, air, and thinner out of the system, and preferably this discharged material is reused.

When applying this example to an actual line,
The color changing unit 20 is fixed near the robot body using a flexible pressure-resistant pipe in the flow path described above, or it is placed on the robot body to connect the second valve means 32 and the third valve means 33 to the robot body. the first of
It is preferable to attach the auto spray gun 21 to the tip of the arm via a bracket so that it can move together with the arm, and to attach the auto spray gun 21 to the wrist because this makes it possible to optimize the weight distribution with respect to the robot arm and the wrist. Then, for example, while synchronizing with a program input to the robot, the opening and closing of each of the valves is digitally controlled by known means in accordance with the process sequence described above.

In the embodiment described above, if the distance between the second valve means 32 and the third valve means 33 is set as short as possible, it is possible to reduce the amount of A color paint remaining in the distance between the two valves. Main valve 33 of three-valve means 33
Piping 50 for supplying pressurized air connected immediately after P
and a fifth valve means 35 for turning on and off the supply of thinner, which is provided in the pipe 50, and a pipe line 6 for supplying thinner.
Even if 0 is omitted, it is practical because the color mixing during color change can be reduced to a small extent and the load on the robot arm can be reduced by the amount of this omission.

As is clear from the detailed explanation above, in the first invention of the present application, the method for changing the color of the paint is carried out not only through the main pressure feeding path for the paint from the color changing unit to the spray gun, but also through a branching line from the main pressure feeding path. Again, using the paint pressure feeding path that includes the auxiliary pressure feeding path connected to the main pressure feeding path, while supplying the developing color paint to the spray gun via the main pressure feeding path, the auxiliary pressure feeding path is filled with the developing color paint prior to the color change time. ,
Next, pressurized air is introduced into the main pressure feeding path to push out the colored paint in the main pressure feeding path to the front of the connection part, closing the part in front of the connecting part, and almost at the same time as this closing, pressurized air is introduced into the auxiliary pressure feeding path. The paint supplied and filled in the sub-pressure feeding path is extruded to continue supplying the paint to the spray gun, and when the pressurized air has filled the path near the spray gun via the sub-pressure feed path, the pressurized air is On the other hand, immediately after the above-mentioned closure, thinner and air are sent to the main pressure feed path from the color change unit to wash the main pressure feed path up to the closed part, and after this cleaning, the next color is After filling the main pressure feeding path up to the closing part with paint and stopping the supply of pressurized air to the auxiliary pressure feeding path, thinner and air are fed to the auxiliary pressure feeding path and sprayed from the auxiliary pressure feeding path. The structure is constructed by cleaning the path leading to the gun tip of the gun, then opening the front part of the connection part and force-feeding the filled next color paint to the spray gun.
Furthermore, in the second invention of the present application, a first valve means located immediately after the color change unit and a first valve means located before the spray gun are provided in the main paint pressure feeding path connecting the color change unit and the spray gun. A second valve means is provided, and a sub-pressure passage to which the current color paint is supplied from the current color paint valve in the color change unit is connected to the first valve from a state in which paint is applied from the current color paint valve in the color change unit. A third valve means connected between the means and the second valve means, and provided in the main pressure feed path on the upstream side of the second valve means, is connected to the third valve means when the color is changed. A discharge passage is provided between the means and the first valve means for discharging cleaning air and thinner from within the main pressure passage, and is connected to a thinner supply source and a pressurized air source and is supplied to the auxiliary pressure passage. A fourth valve means is connected to the first valve means for causing the applied paint to flow into the spray gun and for guiding cleaning air and thinner into the auxiliary pressure feeding path when cleaning the inside of the auxiliary pressure feeding path. Therefore, during the color extrusion process related to the auxiliary pressure feed path, in which the color paint filled in the auxiliary pressure feed path is pushed out using compressed air and supplied to the spray gun, the color change unit in the main pressure feed path is Immediately after the cleaning process, the area extending over the third valve means can be cleaned with thinner and compressed air. Also, the area extending over the third valve means can be filled with the next color paint immediately after the cleaning process. It is now possible to start the filling process and, during the next color paint filling process, to clean the section from the auxiliary pressure feed path following the current color extrusion process related to the auxiliary pressure feed path to the tip of the spray gun. This has the effect of greatly shortening the time from when the supply of the current color paint to the spray gun is stopped until the supply of the next color paint is started (commonly known as the non-painting time related to color change). Furthermore, in the embodiment, since the length between the third valve means and the second valve means in the main pressure feed pipeline is different,
Immediately after the third valve means, a conduit capable of supplying thinner and pressurized air is connected, so that by supplying thinner and pressurized air from the conduit, the third valve means and the second valve means in the main pressure supply conduit are connected. Immediately after completion of the developing color extrusion step related to the sub-pressure-feeding path, washing the section extending between the third valve means and the spray gun in the main pressure-feeding path will fill the main pressure-feeding path. By opening the third valve means, the new color can be supplied to the spray gun, and by setting the section between the third valve means and the spray gun short, the above-mentioned non-painting time can be further shortened. .

[Brief explanation of drawings]

Figure 1 is an overall explanatory diagram of a conventional painting color changing device.
FIG. 2 is an overall explanatory diagram of an embodiment of a paint color changing device used to carry out the first invention of the present application. 3T... Thinner valve of color change unit, 3A...
Automatic opening/closing valve for A color paint in color change unit, 6
...A color paint pressure feed pipe, 11 ...High pressure air source, 1
2...Low pressure air valve, 20...Color change unit, 21
...Auto spray gun, 22... Thinner source,
30... Main pressure feed path, 31... First valve means, 32
...Second valve means, 32P...Main valve, 33...Third valve means, 33D...Automatic valve for air and paint removal, 34...Fourth valve means, 35...Fifth valve means,
...The flow path of the main pressure feed path 30 to the third valve means,
. . . Sub-pressure feeding path, . . . A flow path from the third valve means of the main pressure feeding path 30 to the auto spray gun 21, 40...
... Pipeline, 50... Pipeline for high-pressure air, 60... Pipeline for pressure feeding thinner.

Claims (1)

[Scope of Claims] 1. In addition to the main paint pumping path leading from the color change unit to the spray gun, a paint pumping path is used, which includes a sub-pressing path that branches off from the main pumping path and is connected to the main pumping path again, While supplying the color paint to the spray gun via the main pressure feed path, the auxiliary pressure feed path is filled with the color paint prior to color change, and then pressurized air is fed into the main pressure feed path to fill the main pressure feed path. The existing color paint is pushed out to the front of the connection part, the front part is closed, and almost at the same time as this closing, pressurized air is sent into the auxiliary pressure feeding path to push out the paint filled in the auxiliary pressure feeding path, thereby forming a spray gun. The supply of the pressurized air is continued until the passage near the spray gun is filled with the pressurized air via the auxiliary pressure passage, and then the supply of the pressurized air is stopped. Thinner and air are sent to the main pressure feed path from the replacement unit to clean the main pressure feed path up to the closing portion, and after this cleaning, the main pressure feed path to the closing portion is filled with the next color paint, and After stopping the supply of pressurized air, thinner and air are supplied to the auxiliary pressure feeding path to clean the path from the auxiliary pressure feeding path to the gun tip of the spray gun, and then the front part of the connection part is opened. A method for changing the color of painting, characterized in that the filled next color paint is force-fed to a spray gun. 2. A first valve means located immediately after the color change unit and a second valve means located before the spray gun are provided in the main paint pressure feeding path connecting the color change unit and the spray gun, and From the state in which paint is being applied from the current color paint valve in the changing unit, a sub-pressure passage through which the current color paint is supplied prior to color change is provided between the first valve means and the second valve means. A third valve means connected to the main pressure feeding path and located upstream of the second valve means is provided with the third valve means between the third valve means and the first valve means at the time of the color change. A discharge passage is provided for discharging cleaning air and thinner in the main pressure passage, and is connected to a thinner supply source and a pressurized air source, and also allows the paint supplied in the auxiliary pressure passage to flow out to the spray gun. A paint color changing device comprising a fourth valve means connected to the first valve means for guiding cleaning air or thinner into the auxiliary pressure passage when cleaning the inside of the auxiliary pressure passage.