JPH11179253A - Device for confirming fluid supply switching action - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for confirming a fluid supply switching action in the coating using a color changing device for applying paints of various colors with one coating gun by which the defect that colors are mixed due to the leaking of the paints of other colors in color changing. SOLUTION: The air at a first specified pressure of 5 kgf/cm<2> is supplied to a manifold 20 with switching valves 4a, 4b,... provided to the branch pipelines connected to a paint source. In this case, when the pressure of the air discharged from the outlet of the manifold 20 on the coating gun side is lower than a second specified pressure of 4.8 kgf/cm<2> , the leaking from the switching valves is predetermined (leak check). Further, when an air pulse is supplied plural times to the valve operating air supply ports of the valves 4a, 4b,..., the frequency of the operations of the valves is detected by an on-off counter 51, and whether the valves are defective or not is judged (checking of the operation of a needle valve).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a method of supplying a plurality of paints of different colors to a paint gun and applying a multicolor paint with one paint gun. The present invention relates to a fluid supply switching operation checking device for checking in advance that a problem occurs in which color paint leaks during color change and color mixing occurs.

[0002]

2. Description of the Related Art Conventionally, in a top coating process of an automobile, etc., in order to sequentially paint bodies having different paint colors, a paint gun is used so that a single paint gun can paint multicolor paints. Is provided with a color changing device for sequentially supplying a desired color paint.

As shown in FIG. 5, for example, a paint supply device having such a color changing device includes a coating gun 1 fixed to an automatic coating machine (coating robot) in a coating booth and a coating gun outside the coating booth. A paint supply source (paint tank, paint pump, etc.) 2 installed in
And the paint supply source 2 are connected by paint pipes 3a and 3b. The paint pipes 3a and 3b are provided with a color change valve (CCV) 4 as a color changing device, a flow meter 5 for measuring the flow rate of paint in the pipe, and a paint regulator (flow rate) as a discharge amount control device. Controller) 6,
A dump valve (drain valve) D1 for discarding paint is attached. Although not shown, a trigger valve (discharge valve) that opens when the paint is discharged inside the coating gun 1.
And a dump valve that opens when the previous color remaining in the coating gun is discarded. Further, a gate valve (liquid guide valve) G2 is attached in parallel with the dump valve D1 for cleaning the coating gun 1 and the pipe 3b. The gate valve G2 has a cleaning thinner 7 as a cleaning fluid and a cleaning thinner 7. Air 8 is supplied. Reference numeral 9 in the figure denotes a switching valve for switching between the cleaning thinner 7 and the cleaning air 8.

[0004] The color change valve 4 is composed of a main pipe section communicating with the paint pipe 3a, a plurality of branch pipe sections branching from the main pipe section, and a plurality of switching pipes respectively arranged in the branch pipe section. Are connected to each other, and paints A, B,... Of different colors are connected to the respective branch pipes, and the inside of the pipe 3a from the color change valve 4 to the dam valve D1 is cleaned. Cleaning thinner 10 and cleaning air 11 are connected.
A switching valve in the color change valve 4 is selected by an air signal sent from a control unit of a color changing device (not shown), and a desired paint, thinner, or air is supplied to the coating gun 1 side.

A control air 12 for controlling the paint regulator 6 is supplied to a paint regulator 6 attached to a pipe 3a downstream of the color change valve 4 via an electropneumatic converter or the like (not shown). Paint A supplied to the coating gun 1 by the control air 12,
.. Are determined. The paint regulator that controls the discharge amount of the paint by the control air is an air-operated paint regulator (AOP).
R).

Incidentally, a paint supply device having such a color changing device is disclosed in, for example, JP-A-1-317569, JP-A-2-61565, and 5-
200335.

[0007] The color change in such a paint supply device is conventionally performed as follows.

For example, when the color is changed from the color B to the color A, the color change valve 4 is first switched to select the color B, the trigger valve in the coating gun 1 is opened, and a predetermined discharge from the coating gun 1 is performed. Paint color B in quantity. At this time, the control air 12 to the paint regulator 6 for controlling the discharge amount is set to a predetermined coating pressure. When the coating of the B color is completed, the color change valve 4 is switched to the cleaning air 11, the gate valve G1 and the dump valve D1 are opened, and air is supplied into the pipe 3a to supply the B paint remaining in the pipe 3a. The dump valve D
The liquid is discharged from the drainage pipe 13 into the coating booth. Next, the color change valve 4 is switched to the cleaning thinner 10, and the cleaning thinner 10 is supplied into the pipe 3a in the same manner as the cleaning air 11, to wash off the B color paint adhering to the pipe 3a, and to drain the dump valve D1. Dispose from the pipe 13. The supply cycle of the cleaning air 11 and the cleaning thinner 10 is repeated several times. In parallel with the cleaning of the inside of the pipe 3a, when the coating of the B color is completed, the trigger valve in the coating gun is closed, the dump valve in the coating gun is opened, and the gate valve G2 is also opened to clean the cleaning air 8 and the cleaning air. The thinner 7 and the thinner 7 are alternately supplied to the inside of the pipe 3b and to the coating gun 1, and are discarded from the dump port of the coating gun. Thereby, the inside of the pipe 3b and the coating gun 1 is cleaned.

In a state where these washings have been completed,
The inside of the pipes 3a and 3b is washed with the B color paint and is filled only with air. Then, the A color paint to be painted next is supplied, and after this paint is slightly discarded from the dump port of the dump valve, the dump valve in the paint gun is closed and the trigger valve is opened to wait for the workpiece to arrive. I do.

[0010]

As shown in FIG. 6, the switching valves 4a, 4b... For each color of the color change valve 4 of such a paint supply device are needle valves to which a seal member 23 is attached. 22. When the needle valve 22 is urged upward by the spring 21, the paint from the paint supply hose 24 is closed by the seal member 23 to block the through hole, and the branch pipe section 2 of the manifold 20 is opened.
0b does not flow into the main pipeline 20a. On the other hand, by supplying air at a predetermined pressure from the pilot air supply hose 25 for operating the needle valve,
The needle valve 22 is moved against the resilience of the spring 21, the through hole is closed by the seal member 23, and a predetermined color paint is supplied to the main conduit 20 a of the manifold 20. ing.

However, for example, in the middle / overcoating process or the like, when the color is changed from the switching valve 4b for supplying the B-color paint to the switching valve 4a for supplying the A-color paint different in color, It is said that paint leakage from the switching valve 4b may cause a color mixing problem due to defective or worn parts of the sealing member 23 of the needle valve 22 in the switching valve 4b, or defective or deteriorated part strength of the spring 21. There was a problem.

[0012] In addition, the malfunction of the needle valve 22 and the malfunction of the seal member 23, which cause such a problem, have conventionally been found after a color mixing problem has occurred in a painting process or the like. .

[0013] However, such a color mixing problem surely greatly impairs the coating quality, and causes a situation in which an enormous man-hour for rework such as replacement of parts or re-painting is caused.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems of the prior art, and an object of the present invention is to provide a fluid supply provided with a switching device provided with a pipe portion provided with a switching valve. When supplying a fluid using the device, to provide a confirmation device of the fluid supply switching operation that can check in advance the leakage and malfunction of the switching valve in the switching valve,
In particular, in the case of coating using a color changing device for applying multi-colored paint with one coating gun, fluid supply switching that can prevent in advance the problem that another color paint leaks at the time of color change and color mixing occurs. An object of the present invention is to provide an operation check device.

[0015]

In order to achieve the above object, according to the present invention, there is provided a switching device having a pipe portion in which a switching valve is disposed between a fluid supply source and one outlet. It is a device used for a fluid supply device connected via a, and is a device for confirming a switching operation of supplying a fluid, and when a fluid having a first predetermined pressure set in advance to the pipe portion is supplied,
When the pressure of the fluid discharged from the outlet on the outflow portion side of the pipe portion is smaller than a second predetermined pressure, a determination unit that determines that leakage from the switching valve has occurred is performed. It is characterized by having.

According to a second aspect of the present invention, in the fluid supply switching operation confirming device according to the first aspect, the determining means further comprises a pulsed fluid supplied to the valve operating fluid supply port of the switching valve. Is supplied, the operation of the valve of the switching valve is detected to determine whether there is a malfunction of the valve.

According to a third aspect of the present invention, a plurality of paint supply sources and one coating gun are provided via a color change device provided with a manifold in which a switching valve is disposed in each branch line. A fluid supply switching operation checking device for checking a color change operation of a paint in a multi-color coating for applying a multi-color paint with one coating gun, wherein the manifold is used for a connected paint supply device. A first air supply means for supplying air having a first predetermined pressure set in advance, and a pressure of air discharged from an outlet of the manifold on the coating gun side and a second predetermined pressure set in advance. A comparison means for comparing the pressure of the air discharged from the outlet of the manifold on the side of the coating gun is detected by the comparison means to be smaller than the second predetermined pressure. First alarm means for performing To.

According to a fourth aspect of the present invention, in the fluid supply switching operation checking device according to the third aspect, the second predetermined pressure is set to be smaller than the first predetermined pressure by a predetermined ratio. Features.

According to a fifth aspect of the present invention, in the fluid supply switching operation confirmation device according to the third aspect, the second air supply means for supplying air to a valve operating air supply port of the switching valve. Detecting means for detecting the operation of the valve of the switching valve, and second alarm means for giving an alarm to an operator when there is a malfunction in the operation of the valve based on the detection result of the detecting means. It is characterized by.

According to a sixth aspect of the present invention, in the device for confirming the fluid supply switching operation according to the fifth aspect, the air supply means supplies a predetermined plurality of air pulses, and the detection means comprises: A counter for counting the number of times of operation of the valve, wherein an alarm is issued by the second alarm means when the predetermined number of times of operation is not counted by the counter.

[0021]

According to the present invention, the following effects can be obtained for each claim. According to the first aspect of the invention, it is possible to check in advance for leakage of the switching valve. Therefore, it is possible to reliably avoid the trouble caused by the leakage of the valve.

According to the second aspect of the present invention, it is possible to check in advance the operation failure of the switching valve. Therefore, it is possible to reliably avoid a malfunction due to a malfunction of the valve.

According to the third aspect of the present invention, it is possible to check the leakage of the switching valve of the color changing device in advance, thereby preventing a problem that a different color paint leaks at the time of color changing and color mixing occurs. can do. Therefore, it is possible to reliably avoid a situation in which the painting quality is impaired and a large number of rework steps such as parts replacement and repainting are caused.

According to the fourth aspect of the present invention, a more accurate valve leak check can be performed in consideration of the pressure drop.

According to the fifth aspect of the present invention, it is possible to check in advance the operation failure of the switching valve of the color changing device, and it is possible to prevent a problem that another color paint leaks at the time of color changing and color mixing occurs. Prevention can be surely prevented.

According to the sixth aspect of the present invention, the malfunction of the valve can be more accurately determined.

[0027]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an air circuit diagram of an apparatus for checking a fluid supply switching operation according to an embodiment of the present invention.

The apparatus for confirming the fluid supply switching operation according to the present embodiment comprises a plurality of paint supply sources 2 and 1 shown in FIGS.
Paint gun 1 is connected via a color change valve 4, which is a color change device having a manifold in which switching valves 4a, 4b... It is used when a multi-color paint is applied with one coating gun. Members common to those shown in FIGS. 5 and 6 are denoted by the same reference numerals, and description thereof is omitted.

The apparatus for confirming the fluid supply switching operation shown in FIG. 1 is an apparatus for confirming the color change operation of the paint in the multi-color coating, and the first apparatus which is set in the manifold 20 in advance via the path a.
First air supply means for supplying air having a predetermined pressure. The first air supply means is provided with an air supply source (not shown) and a supplied air at a constant pressure, for example, 5
and an air regulator 31 for reducing the pressure to kg / cm ² . By pressing the start button 32, the air having the first predetermined pressure is released for a time set by the timer 33, for example, 3 seconds, for the main pipeline 20a of the manifold 20.
Is supplied to the side opposite to the exit on the coating gun 1 side.

The first power supplied from an air supply source (not shown)
The air decompressed to the predetermined pressure of 5 kg / cm ² is reduced to a second predetermined pressure, for example, 4.8 kg / cm ² by the air regulator 34 via a path c. The second predetermined pressure can be appropriately set so as to be smaller than the first predetermined pressure by a predetermined ratio in consideration of a pressure drop at each location. The air having the second predetermined pressure is supplied to the path d through the on / off switching valves 36 and 38.
And through the variable throttle section 37, the air destination switching valve 3
5, and the other end of the air destination switching valve 35 is supplied with air passing through the path a and the main conduit 20 a of the manifold 20 through the path b.

In this manner, the air destination switching valve 35 functions as a comparison means for comparing the pressure of the air discharged from the outlet of the manifold 20 on the coating gun side with a second predetermined pressure set in advance. When the pressure of the air discharged from the outlet of the manifold 20 on the coating gun side is smaller than the second predetermined pressure and a differential pressure is generated at both ends of the air destination switching valve 35, the path g and the path f communicate. As a result, the air destination switching valve 49 is operated, whereby the display unit 37 as the first alarm means is provided via the routes i, l, and m.
Is connected so that the NG display is turned on.

On the other hand, when the pressure of the air discharged from the outlet of the manifold 20 on the coating gun side is higher than the second predetermined pressure, the path g and the path o are communicated, and the on / off switching valve 45 Is supplied to the display unit 44 via the paths p, q, and r so that an OK display is turned on.

The fluid supply switching operation checking device includes second air supply means for supplying air to the valve operation air supply ports of the switching valves 4a, 4b. The second air supply means includes an air supply source (not shown) and an air regulator 31 for reducing the supplied air to a first predetermined pressure, for example, 5 kg / cm ^2.
And an air regulator 50 for reducing the pressure for valve operation, for example, 2 kg / cm ² . The air with the valve operating pressure thus obtained is supplied to the on / off switching valve 3
9 are connected via paths y and z so as to be supplied to valve operating air supply ports of the switching valves 4a, 4b.

The on / off switching valve 39 passes through the on / off switching valves 40 and 41 and the paths s, t,
The air supplied through u and x is operated so that the paths y and z communicate with each other. However, the air passing through the path v is delayed by the variable throttle unit 42 and supplied to the on / off switching valve 41, whereby the air to the path x is shut off, and then the paths u and w communicate with each other. When the air is supplied to the on / off switching valve 40 to cut off the path s and the path t, the on / off switching valve 41 and the on / off
The off switching valve 40 is automatically reset.

That is, the above operation is repeated for a time set in advance by the timer 43, for example, for 13 seconds, and as a result, an air pulse is given a plurality of times, in this embodiment ten times, to each of the switching valves 4a, 4b ... can be supplied to the valve operating air supply port.

An on / off counter 51 is provided near the tip of the needle valve 22 of each of the switching valves 4a, 4b. The on / off counter 51 counts the number of times the needle valve 22 is operated. If the count value of the on / off counter 51 matches the number of air pulses supplied to the valve operating air supply port, it is determined that the operation of the needle valve 22 is good. NG is displayed on a display unit as a second alarm unit (not shown).
It is configured to display. The on / off counter 51 can be configured using various micro switches such as a proximity sensor.

In the drawing, reference numeral 46 denotes a pressure gauge, and reference numeral 47 denotes a check valve.

Next, the operation of the present embodiment will be described. FIG. 2 is a main flowchart of the air circuit operation of the present confirmation device, FIG. 3 is a flowchart of a leak check subroutine shown in FIG. 2, and FIG. 4 is a flowchart of a needle valve operation check subroutine shown in FIG. .

As shown in FIG. 2, when the start button 32 is pressed (step S100), a leak check is first performed in advance (step S200). In this leak check, a first predetermined pressure, for example, 5 kg / cm, is applied to the side of the manifold 20 of the color change valve 4 opposite to the outlet on the coating gun 1 side.
Supply ² air. At this time, the pressure of the air discharged from the outlet of the manifold 20 on the coating gun side is 5 kg / cm.
If it remains at ² , for example, there is no leakage from the needle valve (hereinafter also referred to as “leak”), and it is determined that the leak is OK (YES in step S300). If it is determined that the leak is OK, a needle valve operation check is continuously performed in the next step S400. On the other hand, if the pressure of the air discharged from the outlet of the manifold 20 on the coating gun side is smaller than the second predetermined pressure, for example, 4.8 kg / cm ^2, it is determined that a leak has occurred and it is determined that the leak is NG. Is performed (NO in step S300). In this case, the next needle valve operation check is not performed, and the check ends (step S500).

In the needle valve operation check, pulse-like air of, for example, 2 kg / cm ^{2 at} the same level pressure as the line supply is supplied to the valve operation air supply ports of the switching valves 4a, 4b,. At this time, the needle valve 22
The number of actuations of the needle valve 22 is counted by an on / off counter 51 provided near the tip of the needle. If the count value is ten, it is determined that the operation is OK, and if it is less than ten, it is determined that the operation is NG.

Next, the details of the leak check and the needle valve operation check will be described in more detail with reference to FIGS.

As shown in FIG. 3, when the leak check is started, the timer 33 is turned on (step S20).
1) For 3 seconds, air from an air supply source (not shown) is supplied to the air regulator 31 for 5 seconds, for example.
The pressure is reduced to kg / cm ² and supplied to the color change valve 4 on the side opposite to the outlet on the side of the coating gun 1 of the main conduit 20a of the manifold 20 (step S202). This air passes through the main pipeline 20a, is discharged from the outlet on the coating gun 1 side, and is supplied to the switching operation chamber on one end side of the air destination switching valve 35 (step S203).

On the other hand, as shown in FIG. 1, when the on-off valve 49 and the like are open, air is reduced from the air supply source (not shown) to, for example, 5 kg / cm ² by the air regulator 31 in the path c. It has been supplied (step S205). The 5 kg / cm ² air is further reduced to 4.8 kg / cm ² by the air regulator 34 (step S 206), passes through the on / off switching valve 36 via the path d, and the variable throttle 37 , And is sent to the on / off switching valve 38 after a delay of, for example, 3 seconds. Here, the on / off switching valve 38 is initially in an off state because air is supplied to the switching operation chamber via the path e (step S211), but is automatically turned on after the set time of the timer 33 elapses. It returns to the state (YES in step S209). Thereby, the 4.8 kg / cm ² air sent to the on / off switching valve 38 is supplied to the switching operation chamber at the other end of the air destination switching valve 35 (step S210).

In step S212, the air destination switching valve 35 changes the pressure of the air discharged from the outlet of the manifold 20 on the coating gun side to 4.8 kg / cm ² which is the second predetermined pressure. A comparison is made. If the former is smaller than the latter (YE in step S212)
S), the valve of the air destination switching valve 35 moves upward in the figure, and the path g and the path f communicate with each other (step S21).
6). Then, air is supplied to the switching operation chamber of the air destination switching valve 49, and the valve moves upward in the drawing (step S217), and the path i and the path l communicate (step S218). Accordingly, the air displays the leak NG via the paths l and m (step S219), and
Air is supplied to the switching operation chamber of the on / off switching valve 48 via the paths l and n, and the operation check air system from the path h is shut off (step S220).

On the other hand, if it is determined in step S212 that the pressure of the air discharged from the outlet of the manifold 20 on the coating gun side is not lower than the second predetermined pressure (NO in step S212). ), The valve of the air destination switching valve 35 moves downward in the figure, and the path g communicates with the path o (step S213). Then, air is supplied to the switching operation chamber of the air destination switching valve 45, and the valve moves downward in the drawing (step S214), and the path p,
Air is sent through q and r to display a leak OK (step S215), and the process returns. As described above, the leak check is determined after the start button 32 is pressed.
It takes about 3 seconds.

As shown in FIG. 4, the needle valve operation check is performed when the judgment of the leak check is OK. Although partially overlapping the above description, the path g and the path o are communicated by the air destination switching valve 35 (step S4).
01), since the on / off switching valve 48 is in the on state, the valve of the on / off switching valve 45 is moved downward in the figure and is in the on state (step S402). Further, as described above, the air of 5 kg / cm ² is constantly supplied to the path c and the on / off switching valve 48 is in the on state (step S413), so that the air is supplied to the path g and the path p. (Steps S413 and S41)
4). On the other hand, the air passes through the air destination switching valve 49 from the path i (step S416), and turns on the timer 43 via the path k (step S417). The timer 43 has a set time of, for example, 13 seconds, and corresponds to the number of times of generating pulsed air, and can be set as appropriate.

Since the on / off switching valve 45 is on (step S402), the air from the path p is sent from the path s through the on / off switching valve 40 to the path t (step S403). ). The air having passed through the paths t and u is sent to the path x through the on / off switching valve 41 (step S404), and the on / off switching valve 39 is turned on to communicate the path y with the path z. (Step S405). The air decompressed to, for example, 2 kg / cm ² by the air regulator 38 is supplied to the valve operating air supply ports of the switching valves 4a, 4b,... Via the paths y, z (step S40).
6). Next, the needle valve 22 of the switching valve is operated (Step S407), and counted by the on / off counter 51 (Step S408).

On the other hand, the air that has passed through the route t
The air speed is controlled by the variable throttle unit 42 to be delayed (step S418), and supplied to the switching operation chamber of the on / off switching valve 41 to communicate the path u and the path w (step S418). S419). The air that has passed through the path w is now turned on / off switching valve 4
The air is supplied to the switching operation chamber of No. 0, communicates the path s and the path za, and the air from the path s is temporarily discharged (step S420). Therefore, no air is sent to the path t, and the on / off switching valve 40 is automatically turned on by the spring force of the spring (step S42).
1) Returning to step S403, steps S403-
The operation of S408 is repeated for the set time of the timer 43. In this way, a plurality of times of pulsed air is supplied to the valve operating air supply port of the switching valve. In the present embodiment, the process is set to return to step S403 nine times, and the needle valve 22 of the switching valve is operated ten times in total.

In step S409, it is determined whether or not the count value read into the on / off counter 51 is 10 times, which is the same as the number of air pulses supplied to the valve operating air supply port of the switching valve. (Step S409). If this count value is 10 times,
The indication of needle valve operation OK is displayed on a display unit (not shown) (step S410), and if the count value is less than 10, the indication of needle valve operation NG is displayed on the display unit (not shown) (step S411).

As described above, according to the fluid supply switching operation checking device of the present embodiment, in a coating using a color change valve, which is a color changing device for applying a multicolor paint with one coating gun. By simply pressing the start button of the air circuit of the confirmation device, the check is automatically performed offline, and it is possible to prevent a problem that another color paint leaks at the time of color change and color mixing occurs. Therefore, it is possible to reliably avoid a situation in which the painting quality is impaired and a large number of rework steps such as parts replacement and repainting are caused.

The embodiments described above are not described to limit the present invention, and various modifications can be made within the scope of the claims. For example,
In the embodiment described above, the checking device of the fluid supply switching operation for checking the color change operation of the paint in the multicolor coating in which the multicolor paint is applied by one coating gun has been described. In equipment that supplies fluids such as paint and air without being limited to only checking color change operation,
For example, the present invention can also be applied to a device that checks a switching operation for supplying a fluid using an on / off operation by a needle valve or the like.

[Brief description of the drawings]

FIG. 1 is an air circuit diagram of an apparatus for checking a fluid supply switching operation according to an embodiment of the present invention.

FIG. 2 is a main flowchart of an air circuit operation of the confirmation device.

FIG. 3 is a flowchart of a leak check subroutine shown in FIG. 2;

FIG. 4 is a flowchart of a subroutine of a needle valve operation check shown in FIG. 2;

FIG. 5 is a piping diagram of a paint supply device.

FIG. 6 is a partially enlarged sectional view of a switching valve for each color of a color change valve of the paint supply device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Coating gun (outflow part), 2 ... Paint supply source, 4 ... Color change valve (color changing device, switching device), 4a, 4b ... Switching valve, 20 ... Manifold (tube part), 20a ... Trunk line Reference numeral 20b: Branch pipe section 35: Air destination switching valve (comparing means) 37: Display section (first alarm means) 51: On / off counter (detecting means)

Claims (6)

[Claims] 1. A switching operation for supplying a fluid, which is used in a fluid supply device in which a fluid supply source and one outflow portion are connected via a switching device having a pipe portion provided with a switching valve. An apparatus for confirming, wherein, when a fluid having a first predetermined pressure set in advance is supplied to the pipe portion, a pressure of a fluid discharged from an outlet of the pipe portion on the outlet side is set to a predetermined pressure. A fluid supply switching operation checking device, characterized in that it has a judging means for judging that a leak from the switching valve has occurred when the pressure is smaller than a predetermined pressure of 2. 2. The method according to claim 1, wherein when the fluid is supplied to the valve operating fluid supply port of the switching valve in a pulsed manner, the determination unit detects an operation of the switching valve.
The fluid supply switching operation check device according to claim 1, wherein it is determined whether or not the valve has a malfunction. 3. A paint supply apparatus in which a plurality of paint supply sources and one paint gun are connected via a color change device having a manifold in which a switching valve is disposed in each branch pipe section. And a fluid supply switching operation confirming device for confirming a color change operation of the paint in the multicolor painting in which the multicolor paint is applied by one painting gun, wherein the first predetermined preset in the manifold is provided. First air supply means for supplying air at a pressure; comparison means for comparing the pressure of air discharged from the outlet of the manifold on the coating gun side with a second predetermined pressure set in advance; A first alarm unit for issuing an alarm to an operator when the comparing unit detects that the pressure of the air discharged from the outlet on the coating gun side of the manifold is smaller than the second predetermined pressure; Confirmation of fluid supply switching operation characterized by having apparatus. 4. The apparatus according to claim 3, wherein the second predetermined pressure is set to be smaller than the first predetermined pressure by a predetermined ratio. 5. A second air supply means for supplying air to a valve operation air supply port of the switching valve, a detection means for detecting an operation of a valve of the switching valve, and a detection result obtained by the detection means. 4. The fluid supply switching operation confirming device according to claim 3, further comprising: a second warning unit that gives a warning to an operator when there is a malfunction in the operation of the valve. 6. The air supply means supplies a predetermined plurality of air pulses, and the detection means is a counter for counting the number of times of operation of the valve. 6. The apparatus according to claim 5, wherein an alarm is issued by the second alarm unit when the number of times is not counted.