JP7048044B2 - Painting equipment - Google Patents

Description

The present invention relates to a coating apparatus.

Patent Document 1 discloses a coating device including a coating gun that ejects paint and a switching valve that selectively supplies any one of a plurality of types of paint toward the coating gun. .. In such a painting device, when switching the type of paint, the paint remaining in the paint gun is once washed with a cleaning liquid so as not to be mixed with the newly supplied paint. During cleaning, the cleaning liquid is discharged from the paint gun while being mixed with the paint before switching, and cleaning is completed when the paint is no longer mixed with the discharged cleaning liquid. When the cleaning is completed, the cleaning liquid remains in the flow path, and new paint is supplied in this state. Therefore, at the beginning, the paint mixed with the cleaning liquid is discharged from the paint gun. After that, when the cleaning liquid is no longer mixed with the discharged paint, the filling of the paint is completed. The completion of the filling of the paint was determined by detecting that the elapsed time from the start of the supply of the new paint exceeded a preset time.

Japanese Unexamined Patent Publication No. 2009-136743

However, since the components contained in the paint differ depending on the type, the speed at which the paint is supplied also differs depending on the type of paint, and as a result, the time required to complete filling also differs depending on the type of paint. For this reason, if the filling time is set according to the paint that takes the longest time to fill, regardless of the type of paint, the paint is wasted when the filling time is short. It ends up. Further, in order to avoid such a situation, it is conceivable to set the filling time for each type of paint, but there is a problem that it takes time and effort to determine and set an appropriate filling time for each type of paint. Furthermore, even if the same paint is used, the viscosity may differ due to differences in air temperature and liquid temperature, and the time required for filling may change. Taking these circumstances into consideration, setting a longer filling time wastes the paint. There is also a problem that it becomes easy to discharge.

The present invention has been made in view of the above-mentioned conventional circumstances, and it is an object to be solved to provide a coating apparatus capable of suppressing unnecessary ejection of paint.

The painting apparatus of the present invention is
With a paint gun,
Multiple paint sources that individually supply different types of paint to the paint gun,
A switching valve provided between the paint gun and the plurality of paint supply sources to switch the type of paint supplied to the paint gun.
A cleaning liquid supply source connected to the switching valve via the cleaning liquid supply path and supplying the cleaning liquid toward the coating gun, and a cleaning liquid supply source.
A first light emitting unit, a first light receiving unit, and a second light emitting unit arranged so as to face the common flow path from the outlet of the switching bulb to the discharge port of the coating gun.
A second light receiving unit that receives light that is projected from the second light projecting unit and reflected by the fluid in the common flow path.
A cleaning determination for determining whether or not the cleaning in the common flow path is completed based on the amount of light projected from the first light projecting section, passing through the common flow path, and received by the first light receiving section. Department and
A filling determination unit that determines whether or not the filling of a desired type of paint in the common flow path is completed based on the reflected light received by the second light receiving unit.
A first optical fiber cable having the first light emitting part and the first light receiving part at the tip thereof,
A second optical fiber cable having the second light emitting portion and the second light receiving portion at the tip thereof, and the tip portion is arranged so as to face the same direction as the traveling direction of the paint in the common flow path.
Equipped with
When the cleaning determination unit determines that the cleaning in the common flow path is completed, the process proceeds to supply a new paint.

In the coating apparatus of the present invention, when cleaning is completed and new paint is supplied, the new paint is discharged while being mixed with the cleaning liquid remaining in the common flow path, and the ratio of the cleaning liquid in the common flow path is gradually increased. On the other hand, the proportion of paint in the common flow path gradually increases. Then, when the paint is filled in the entire common flow path, the light receiving portion receives the light reflected by the paint filled in the common flow path. Therefore, it is possible to detect whether or not the reflective material is a desired type of paint based on the reflected light, so that the filling of the paint is completed at the timing when the common flow path is filled with the new paint. As a result, it is possible to suppress unnecessary ejection of the paint.
Further, when an electronic device including a photoelectric element for receiving and receiving light is placed in a painting booth, it is necessary to make the electronic device an explosion-proof structure so that the paint does not catch fire. In this respect, in the coating apparatus of the present invention, the first light emitting part and the first light receiving part are provided at the tip of the first optical fiber cable that does not require energization, and the second light emitting part and the second light receiving part are provided at the tip of the second optical fiber cable. Since the light receiving unit is provided, the first light emitting unit, the first light receiving unit, the second light emitting unit, and the second light receiving unit can be arranged in the painting booth without having an explosion-proof structure.

It is a schematic diagram of the coating apparatus of Example 1. FIG. It is a schematic diagram which showed the state which the 1st optical fiber cable was installed. It is sectional drawing of the 1st optical fiber cable in the arrow view AA part of FIG. It is a schematic diagram which showed the state which the 2nd optical fiber cable was installed. It is sectional drawing of the 2nd optical fiber cable in the arrow view BB part of FIG. It is a block diagram which showed the electric composition of a painting apparatus. It is a flowchart of the process of cleaning the inside of a common flow path. It is a flowchart of the process of filling a paint gun with paint.

( 1 ) In the painting apparatus of the present invention, the second light projecting unit may be arranged so as to face the flow path from the outlet of the switching valve to the supply port of the painting gun in the common flow path. ..
By doing so, the second light emitting section and the second light receiving section can be incorporated into the painting device without changing the design of the structure of the painting gun, so that the second light emitting section and the second light receiving section can be easily incorporated into the painting device. Can be installed.

<Example 1>
Hereinafter, Example 1 embodying the present invention will be described with reference to FIGS. 1 to 8.

<Painting device 10>
The coating apparatus 10 of the first embodiment spray-coats an object to be coated with a solvent-based paint, and enables painting with a plurality of types of paint by switching the type of paint. As shown in FIG. 1, the coating apparatus 10 includes a coating gun 20, a plurality of paint supply sources 30, a cleaning liquid supply source 34, an air supply source 36, and a switching valve 38.

The coating gun 20 coats the object to be coated by ejecting the paint in the form of mist. A supply port 22 for supplying paint is formed at the rear end of the paint gun 20. A discharge port 24 for discharging the paint supplied from the supply port 22 is formed at the tip of the paint gun 20. The coating gun 20 is formed with a common flow path 54 in the gun connecting the supply port 22 and the discharge port 24. The paint supplied from the supply port 22 is sent to the discharge port 24 through the common flow path 54 in the gun. The common flow path 54 in the gun is formed of a tubular member. This tubular member is made of, for example, an insulating resin (for example, a fluororesin).

The plurality of paint supply sources 30 individually supply different types of paint to the paint gun 20. Here, the type of paint means one classified according to the components (resin material, pigment, additive, etc.) contained in the paint. In this embodiment, the pigment contained in each paint is different, and the color is different depending on the type of paint. Each paint supply source 30 has a tank for storing paint (not shown) and a pump (not shown) for supplying the paint in this tank to the paint gun 20. Each paint supply source 30 is connected to a switching valve 38 via a paint supply path 31 provided corresponding to each, and the paint gun 20 is connected to the switching valve 38 and a common flow path 52 for supply described later. It is connected to the.

The plurality of paint supply sources 30 include a first paint supply source 30A for supplying at least the first paint (for example, blue paint) and a second paint supply source 30B for supplying the second paint (for example, red paint). I'm out. As the paint supply path 31, at least the first paint supply path 31A provided corresponding to the first paint supply source 30A and the second paint supply path 31B provided corresponding to the second paint supply source 30B are included. exist.

The cleaning liquid supply source 34 supplies a cleaning liquid (for example, an organic solvent such as thinner) toward the coating gun 20. The cleaning liquid supply source 34 has a tank for storing the cleaning liquid (not shown) and a pump (not shown) for supplying the cleaning liquid of this tank toward the painting gun 20. The cleaning liquid supply source 34 is connected to the switching valve 38 via the cleaning liquid supply path 35, and is connected to the coating gun 20 via the switching valve 38 and the supply common flow path 52 described later.

The air supply source 36 supplies air toward the paint gun 20. The air supply source 36 has a compressor (not shown), and pumps the air compressed by the compressor. The air supply source 36 is connected to the switching valve 38 via the air supply path 37, and is connected to the coating gun 20 via the switching valve 38 and the common supply flow path 52 described later.

The switching valve 38 is provided on the downstream side of the plurality of paint supply sources 30, the cleaning liquid supply source 34, and the air supply source 36, and on the upstream side of the coating gun 20. That is, the switching valve 38 is provided between the coating gun 20 and the plurality of paint supply sources 30, the cleaning liquid supply source 34, and the air supply source 36. The switching valve 38 is connected to the paint gun 20 via the common flow path 52 for supply. The common flow path 52 for supply is formed of a hose (not shown) made of an insulating resin (for example, fluororesin). The common flow path 52 for supply constitutes a common flow path 54 in the gun in the paint gun 20 and a common flow path 50 connecting the outlet 39 of the switching valve 38 and the discharge port 24 of the paint gun 20.

The switching valve 38 has a plurality of paint valves 40 connected to the downstream end of each paint supply path 31. Specifically, it has at least a first paint valve 40A connected to the downstream end of the first paint supply path 31A and a second paint valve 40B connected to the downstream end of the second paint supply path 31B. There is. Further, the switching valve 38 has a cleaning liquid valve 44 connected to the downstream end of the cleaning liquid supply path 35 and an air valve 46 connected to the downstream end of the air supply path 37. As a result, the switching valve 38 individually switches the open / closed state of the paint valve 40, the cleaning liquid valve 44, and the air valve 46, so that any one of a plurality of types of paint, cleaning liquid, or air can be applied to the painting gun 20. Can be selectively supplied toward.

<First optical fiber cable 70>
As shown in FIGS. 1 and 2, the painting apparatus 10 includes a first block 60, a first optical fiber cable 70, a first light emitting element 76, and a first light receiving element 78. The first block 60 is made of, for example, aluminum and has a substantially rectangular parallelepiped shape. The flow path 62 in the first block is formed through the first block 60. The flow path 62 in the first block constitutes a part of the common flow path 50. The cross-sectional shape of the flow path 62 in the first block is circular. The upstream end of the flow path 62 in the first block is continuous with the downstream end of the flow path 82 in the second block, which will be described later, and the downstream end of the flow path 62 in the first block is upstream of the common flow path 54 in the gun. It is continuous at the end.

The first block 60 is formed with a first accommodating portion 64 into which one end of the first optical fiber cable 70 is fitted. The cross-sectional shape of the first accommodating portion 64 is circular. One end of the first accommodating portion 64 opens to the outer surface of the first block 60, and the other end communicates orthogonally with the flow path 62 in the first block. The first accommodating portion 64 is formed on both sides of the flow path 62 in the first block. Hereinafter, each first accommodating portion 64 will be described with the side of the flow path 62 in the first block of the first accommodating portion 64 as the inside and the opposite side as the outside. Each first accommodating portion 64 is gradually reduced in diameter in the order of an outer portion, an intermediate portion, and an inner portion.

As shown in FIG. 3, the first optical fiber cable 70 includes a first optical fiber 71 and a first coating 72 that covers the outer periphery of the first optical fiber 71. A cylindrical first head 74 that surrounds the outer circumference of the first optical fiber cable 70 is fitted to one end of the first optical fiber cable 70. The first head 74 has an elongated inner cylinder attached to the first optical fiber cable 70, and an outer cylinder that covers the outer circumference of the inner cylinder. Both ends of the inner cylinder protrude in the axial direction from both ends of the outer cylinder. The outer cylinder is supported by the inner cylinder in a state in which it can rotate around the central axis as a rotation axis. A screw groove is formed on the outer peripheral surface of the outer cylinder.

The first head 74 is attached to the first optical fiber cable 70 with the first optical fiber cable 70 slightly protruding from the tip thereof. Hereinafter, the first optical fiber cable 70 will be described with the end portion on the side where the first head 74 is fitted as the tip end portion and the end portion on the opposite side as the base end portion.

Two first optical fiber cables 70 are provided, and their respective tip portions are fitted into the first accommodating portions 64 of the first block 60. The outer diameter of the outer cylinder of the first head 74 is slightly smaller than the diameter of the outer diameter of the first accommodating portion 64. The outer diameter of the inner cylinder of the first head 74 is slightly smaller than the diameter of the intermediate portion of the first accommodating portion 64. The outer diameter of the first optical fiber cable 70 is slightly smaller than the diameter of the inner portion of the first accommodating portion 64. As a result, the tip of the first optical fiber cable 70 protruding from the tip of the first head 74 fits into the inner portion of the first accommodating portion 64. The inner cylinder of the first head 74 fits into the intermediate portion of the first accommodating portion 64. The outer cylinder of the first head 74 is fitted into the outer portion of the first accommodating portion 64.

A screw groove is formed on the inner peripheral surface of the first accommodating portion 64. The first optical fiber cable 70 and the first head 74 are fixed to the first block 60 by screwing the outer cylinder of the first head 74 into the first accommodating portion 64. Each first optical fiber cable 70 is fixed to the first block 60 so that the tip end thereof faces the flow path 62 in the first block. More specifically, the tips of the pair of first optical fiber cables 70, 70 are arranged so as to coaxially face each other with the flow path 62 in the first block interposed therebetween. Further, in the state where each first optical fiber cable 70 is fixed to the first block 60, the tip portion thereof is exposed to the flow path 62 in the first block. The exposed portion (the tip of each first optical fiber cable 70) is coated with an insulating resin (for example, fluororesin). Further, a first seal member is provided between the first accommodating portion 64 and the first optical fiber cable 70 so that a fluid such as paint flowing through the flow path 62 in the first block does not leak to the outside from the first accommodating portion 64. 66 (for example, an O-ring) is fitted.

Of the two first optical fiber cables 70, the first light emitting element 76 is provided in the vicinity of the base end portion of one of the first optical fiber cables 70. The first light emitting element 76 can be, for example, an LED, and more specifically, a red LED. On the other hand, the first optical fiber cable 70 receives the light emitted by the first light emitting element 76 at the base end portion and projects the received light from the tip end portion. In the following, one of the first optical fiber cables 70 will be referred to as a "first optical fiber cable 70A for floodlighting", and the tip of the first optical fiber cable 70A for floodlighting will be referred to as a "first floodlighting portion 73A". It is called.

The tip of the other first optical fiber cable 70 can receive the light projected by the first optical fiber cable 70A for light projection. Hereinafter, the other first optical fiber cable 70 will be referred to as a “first optical fiber cable 70B for light reception”, and the tip of the first optical fiber cable 70B for light reception will be referred to as a “first light receiving unit 73B”. The first optical fiber cable 70B for receiving light emits the light received from the first light receiving portion 73B from the base end portion. A first light receiving element 78 is provided in the vicinity of the base end portion of the first optical fiber cable 70B for receiving light, and when light is emitted from the base end portion of the first optical fiber cable 70B for receiving light, the light is emitted. The first light receiving element 78 receives the light. The first light receiving element 78 can be, for example, a photodiode.

The above-mentioned paint gun 20, the switching valve 38, the common flow path 50, the first block 60, and the tip portions (first light emitting portion 73A and first light receiving portion 73B) of the first optical fiber cable 70 are shown in FIG. As described above, it is arranged in the explosion-proof area A1 (inside the painting booth), which needs to have an explosion-proof structure. On the other hand, the base end portion of the first optical fiber cable 70, the first light emitting element 76, the first light receiving element 78, and the control unit 100 described later do not need to have an explosion-proof structure, and the non-explosion-proof area A2 (outside the painting booth). Is located in.

<Second optical fiber cable 90>
As shown in FIGS. 1 and 4, the coating apparatus 10 includes a second block 80, a second optical fiber cable 90, a second light emitting element 96, and a second light receiving element 98. The second block 80 is made of, for example, aluminum and has a substantially rectangular parallelepiped shape. The second block 80 is formed so as to penetrate the flow path 82 in the second block. The flow path 82 in the second block constitutes a part of the common flow path 50. The cross-sectional shape of the flow path 82 in the second block is circular. The upstream end of the second block inner flow path 82 is continuous with the downstream end of the common supply flow path 52, and the downstream end of the second block inner flow path 82 is the upstream end of the first block inner flow path 62. It is continuous. Although the second block 80 is arranged on the upstream side of the first block 60, it may be arranged on the downstream side of the first block 60. Further, although the first block 60 and the second block 80 are adjacent to each other, they may be separated from each other.

The flow path 82 in the second block is bent in the middle. Specifically, the flow path 82 in the second block has a first flow path 82A, a second flow path 82B, and a third flow path 82C. The first flow path 82A communicates with the opening on the upstream side of the second block 80 and extends linearly. The second flow path 82B extends linearly at right angles to the downstream end of the first flow path 82A. The third flow path 82C extends linearly orthogonally to the downstream end of the second flow path 82B and communicates with the downstream opening of the second block 80.

The second block 80 is formed with a second accommodating portion 84 into which the second optical fiber cable 90 is fitted. One end of the second accommodating portion 84 opens to the outer surface of the second block 80, and the other end communicates with the flow path 82 in the second block. The second accommodating portion 84 communicates with the bent portion of the second block inner flow path 82, and is arranged so as to extend in the extending direction of the second block inner flow path 82 that communicates with the second block inner flow path 82. Specifically, the other end of the second accommodating portion 84 communicates with the upstream end of the third flow path 82C, and is arranged so as to extend in the extension direction on the upstream side of the third flow path 82C. There is. Since the shape of the second accommodating portion 84 is the same as the shape of the first accommodating portion 64 described above, the description thereof will be omitted.

As shown in FIG. 5, the second optical fiber cable 90 includes a plurality of (here, two) second optical fibers 91 and a second coating 92 that covers the outer periphery of the plurality of second optical fibers 91. It will be. The plurality of second optical fibers 91 include at least one (here, one) light-emitting optical fiber 91A and at least one (here, one) light-receiving optical fiber 91B.

The second optical fiber cable 90 has a collective cable portion 90A, a branch portion 90B, a floodlight cable portion 90C, and a light receiving cable portion 90D. In the following, the second optical fiber cable 90 will be described with the collective cable section 90A side as the tip end side and the floodlight cable section 90C and the light receiving cable section 90D side as the base end side. The optical fiber 91A for floodlight extends from the base end of the floodlight cable portion 90C to the tip of the collective cable portion 90A through the branch portion 90B. The light receiving optical fiber 91B extends from the base end of the light receiving cable portion 90D to the tip of the collective cable portion 90A through the branch portion 90B. That is, in the collective cable section 90A, the light projecting optical fiber 91A and the light receiving optical fiber 91B are combined into one cable.

A cylindrical second head 94 that surrounds the outer circumference of the second optical fiber cable 90 is fitted in the tip of the second optical fiber cable 90. The second head 94 is attached to the second optical fiber cable 90 with the second optical fiber cable 90 slightly protruding from the tip. Since the shape and structure of the second head 94 are the same as the shape and structure of the first head 74 described above, the description thereof will be omitted.

The second optical fiber cable 90 is fitted from the tip end into the second accommodating portion 84 of the second block 80. The outer diameter of the outer cylinder of the second head 94 is slightly smaller than the diameter of the outer diameter of the second accommodating portion 84. The outer diameter of the inner cylinder of the second head 94 is slightly smaller than the diameter of the intermediate portion of the second accommodating portion 84. The outer diameter of the second optical fiber cable 90 is slightly smaller than the diameter of the inner diameter of the second accommodating portion 84. Therefore, the tip of the second optical fiber cable 90 protruding from the tip of the second head 94 fits into the inner portion of the second accommodating portion 84. The inner cylinder of the second head 94 fits into the intermediate portion of the second accommodating portion 84. The outer cylinder of the second head 94 is fitted into the outer portion of the second accommodating portion 84.

A screw groove is formed on the inner peripheral surface of the second accommodating portion 84. The second optical fiber cable 90 and the second head 94 are fixed to the second block 80 by screwing the outer cylinder of the second head 94 into the second accommodating portion 84. The second optical fiber cable 90 is fixed to the second block 80, so that the tip portion thereof is arranged in a bent portion of the flow path 82 in the second block so as to face the same direction as the traveling direction of the paint. More specifically, the second optical fiber cable 90 is arranged with the tip end facing the same direction as the traveling direction of the paint in the third flow path 82C at the upstream end of the third flow path 82C. .. The downstream end of the third flow path 82C communicates with the upstream end of the linear first block inner flow path 62, and the downstream end of the first block inner flow path 62 communicates with the supply port 22 of the coating gun 20. Therefore, the tip of the second optical fiber cable 90 is arranged so as to face the supply port 22 of the paint gun 20. Further, in the state where the second optical fiber cable 90 is fitted in the second accommodating portion 84, the tip portion thereof is exposed to the flow path 82 in the second block. This exposed portion (the tip end portion of the second optical fiber cable 90) is coated with an insulating resin (for example, fluororesin). Further, a second seal member is provided between the second accommodating portion 84 and the second optical fiber cable 90 so that the fluid such as paint flowing through the flow path 82 in the second block does not leak to the outside from the second accommodating portion 84. An 86 (eg, an O-ring) is fitted.

A second light emitting element 96 is provided in the vicinity of the base end portion on the floodlight cable portion 90C side of the second optical fiber cable 90. The second light emitting element 96 can be, for example, an LED, and more specifically, a white LED. The second optical fiber cable 90 receives the light emitted by the second light emitting element 96 at the base end portion through the light projecting optical fiber 91A, and projects the received light from the tip end portion. Therefore, in the following, the tip end portion of the light projecting optical fiber 91A will be referred to as a “second light projecting unit 93A”. The second light projecting unit 93A is arranged so as to face the flow path 82 (common flow path 50) in the second block.

In the second optical fiber cable 90, the light reflected by the fluid (paint, cleaning liquid, mixed flow thereof) in the common flow path 50, which is projected by the second light projecting unit 93A, is transmitted from the tip of the light receiving optical fiber 91B. Can receive. Therefore, in the following, the tip end portion of the light receiving optical fiber 91B will be referred to as a “second light receiving unit 93B”. The light receiving optical fiber 91B emits the light received from the second light receiving unit 93B from the base end portion. A second light receiving element 98 is provided in the vicinity of the base end portion of the light receiving optical fiber 91B, and when light is emitted from the base end portion of the light receiving optical fiber 91B, the second light receiving element 98 emits the light. Receive. The second light receiving element 98 is, for example, a three-channel photodiode having sensitivity to each of red light (wavelength = 620 to 750 nm), green light (wavelength = 495 to 570 nm), and blue light (wavelength = 450 to 495 nm). Can be.

The coating gun 20, the switching valve 38, the common flow path 50, the second block 80, and the tip portions (second light emitting portion 93A and second light receiving portion 93B) of the second optical fiber cable 90 have an explosion-proof structure. It is located in the explosion-proof area A1 (inside the painting booth) where it is necessary. On the other hand, the base end portion of the second optical fiber cable 90, the second light emitting element 96, the second light receiving element 98, and the control unit 100 described later do not need to have an explosion-proof structure, and the non-explosion-proof area A2 (outside the painting booth). Is located in.

The second optical fiber cable 90 corresponds to the "optical fiber cable" of the present invention, the second light projecting unit 93A corresponds to the "light projecting unit" of the present invention, and the second light receiving unit 93B corresponds to the "light receiving unit 93B" of the present invention. Corresponds to the "light receiving part".

<Electrical configuration of painting device 10>
As shown in FIG. 6, the painting device 10 includes a control unit 100 that controls the switching valve 38. The control unit 100 has, for example, a microcomputer. The control unit 100 is electrically connected to the first light emitting element 76 and the first light receiving element 78 described above, can control the light emitting state of the first light emitting element 76, and is received by the first light receiving element 78. It is possible to receive an electric signal indicating the amount of light (hereinafter referred to as "transmitted light").

The control unit 100 has functions as a bulb control unit 102, a transmitted light acquisition unit 110, a cleaning determination value storage unit 112, and a cleaning determination unit 114. The valve control unit 102 is electrically connected to the switching valve 38 (each paint valve 40, cleaning liquid valve 44 and air valve 46), and controls the open / closed state of each paint valve 40, cleaning liquid valve 44 and air valve 46. be able to. The transmitted light acquisition unit 110 can acquire the amount of transmitted light. The cleaning determination value storage unit 112 stores a cleaning determination value that serves as a threshold value when determining whether or not cleaning in the common flow path 50 is completed. The cleaning determination value may be a value set in advance or a value arbitrarily set by the user. The cleaning determination unit 114 determines whether or not the cleaning in the common flow path 50 is completed based on the amount of transmitted light and the cleaning determination value. During cleaning, the paint before switching is mixed with the cleaning liquid discharged from the painting gun, and cleaning is completed when the paint is no longer mixed with the cleaning liquid discharged.

The control unit 100 is electrically connected to the second light emitting element 96 and the second light receiving element 98 described above, can control the light emitting state of the second light emitting element 96, and is received by the second light receiving element 98. It is possible to receive an electric signal indicating the amount of light (hereinafter referred to as "reflected light").

The control unit 100 has functions as a reflected light acquisition unit 120, a paint identification information storage unit 122, and a filling determination unit 124. The reflected light acquisition unit 120 acquires the amount of reflected light. The paint identification information storage unit 122 stores paint identification information for identifying the type of paint. The filling determination unit 124 determines whether or not the reflected material is the paint to be filled, based on the amount of reflected light and the paint identification information. As a result, if it is determined that the paint is to be filled, it is determined that the filling of the paint is completed. On the contrary, when it is determined that the paint is not to be filled, it is determined that the filling of the paint is not completed. In this way, it is determined whether or not the filling of the paint is completed. During the filling of the paint, the cleaning liquid is mixed with the paint discharged from the paint gun, and when the cleaning liquid is no longer mixed with the discharged paint, the filling is completed.

<Action of Example 1>
When the painting apparatus 10 detects a work (object to be coated) flowing to the painting line, the painting device 10 identifies the type of the work and paints with the type of paint corresponding to the work. At this time, the painting apparatus 10 determines whether or not the color change is necessary, and as a result, if it is determined that the color change is not necessary, the painting is continued as it is. On the other hand, when it is determined that the color needs to be changed, the inside of the common flow path 50 is once washed so that the paint remaining in the painting gun 20 is not mixed.

When cleaning the inside of the common flow path 50, the painting device 10 first closes the open paint valve 40 as shown in the flowchart of FIG. 7 (step S10). For example, when switching from the first paint to the second paint, the open first paint valve 40A is closed. At this point, the paint remains on the switching valve 38 and the entire common flow path 50. In this state, the coating apparatus 10 opens the cleaning liquid valve 44 and supplies the cleaning liquid to the switching valve 38 and the common flow path 50 (step S11). The cleaning liquid supplied to the switching valve 38 and the common flow path 50 flows down while being mixed with the paint remaining in the common flow path 50 before switching. When a predetermined time (for example, 0.5 seconds) has elapsed after opening the cleaning liquid valve 44, the cleaning liquid valve 44 is closed.

After closing the cleaning liquid valve 44, the painting apparatus 10 opens the air valve 46 to supply air to the switching valve 38 and the common flow path 50 (step S12). The speed of the supplied air is faster than the speed of the cleaning liquid. Therefore, the air is pressure-fed toward the discharge port 24 while being mixed with the paint before switching and the cleaning liquid previously supplied. The painting device 10 closes the air valve 46 when a predetermined time (for example, 5 seconds) has elapsed after opening the air valve 46. Then, the amount of transmitted light received by the first light receiving element 78 is acquired (step S13).

When the coating apparatus 10 acquires the amount of transmitted light, it determines whether or not the amount of light is equal to or greater than the cleaning determination value (step S14). If the amount of transmitted light is less than the cleaning determination value (step S14: NO), the process returns to step S11, and the processes of steps S11 to S14 are repeated until the amount of transmitted light becomes equal to or greater than the cleaning determination value. That is, the inside of the common flow path 50 is cleaned by alternately supplying the cleaning liquid and air until the amount of transmitted light becomes equal to or higher than the cleaning determination value. During this period, the proportion of the cleaning liquid and the air in the common flow path 50 increases, and the proportion of the paint before switching decreases. When the amount of transmitted light exceeds the cleaning determination value (step S14: YES), it is determined that the paint before switching is discharged from the common flow path 50 and the cleaning in the common flow path 50 is completed (step). S15). In the state where it is determined that the cleaning is completed, the air and the cleaning liquid that could not be completely discharged remain in the common flow path 50. When the coating apparatus 10 determines that the cleaning is completed, the coating apparatus 10 moves to a process of supplying new paint.

When supplying new paint, the painting device 10 first opens the paint valve 40 of the paint supplied to the painting gun 20 (step S20), as shown in the flowchart of FIG. For example, when switching from the first paint to the second paint, the second paint valve 40B is opened. By doing so, the paint is supplied to the switching valve 38 and the common flow path 50. At this time, the paint after switching is supplied while being mixed with the air and the cleaning liquid remaining in the common flow path 50. After opening the paint valve 40, the paint device 10 reads out the paint identification information corresponding to the type of paint to be supplied (step S21).

The paint identification information is information showing the reflectance of each paint, and more specifically, information showing the reflectance of red light, green light, and blue light for each paint. The paint identification information may be a preset value, a value arbitrarily set by the user, or an actually measured value actually measured with the paint filled. After reading the paint identification information, the painting apparatus 10 sets a determination range including an error range in the paint identification information (step S22). The width regarded as an error may be a preset width or a width arbitrarily set by the user.

After reading the paint identification information, the painting apparatus 10 acquires the amount of reflected light detected by the three-channel photodiode having sensitivity to each of the red light, the green light, and the blue light (step S23). Then, for each reflected light detected by each photodiode, it is determined whether or not the amount of light falls within the determination range corresponding to each emission color (step S24). As a result, if any one of them is not within the judgment range (step S24: NO), it is determined that the paint is not the paint to be filled with the reflected material, and reflection is performed until all of them are within the judgment range. The amount of light is acquired, and it is repeatedly determined whether or not the amount of reflected light is within the determination range. During this period, the proportion of the paint after switching increases in the common flow path 50, and the proportion of the cleaning liquid decreases. When the amount of reflected light falls within the determination range for all emission colors (step S24: YES), it is determined that the paint is to be filled with the reflected material, and the cleaning liquid is discharged from the common flow path 50. , It is determined that the entire inside of the common flow path 50 is filled with the paint (step S25). When it is determined that the paint is filled, the supply of the paint is temporarily stopped, and then the painting is started.

<Effect of Example 1>
As described above, in the coating apparatus 10 of the present embodiment, any kind of paint or cleaning liquid is selected for the coating gun 20, the plurality of paint supply sources 30, the cleaning liquid supply source 34, and the coating gun 20. The first light emitting unit 73A and the first light receiving unit 73B arranged so as to face the common flow path 50 connecting the switching valve 38 to be supplied in a positive manner, the outlet 39 of the switching valve 38, and the discharge port 24 of the paint gun 20. Based on the amount of light emitted from the first light emitting unit 73A, passing through the common flow path 50, and received by the first light receiving unit 73B, it is determined whether or not the cleaning in the common flow path 50 is completed. .. In the coating apparatus 10, during cleaning, the cleaning liquid is discharged while being mixed with the paint before switching, the proportion of the paint in the common flow path 50 gradually decreases, and as the proportion of this paint decreases, the first The amount of light received by the light receiving unit 73B increases. Therefore, it is possible to detect the timing at which all the cleaning liquid mixed with the paint is discharged from the common flow path 50 based on the amount of light, and it can be determined that the cleaning is completed at that timing. This makes it possible to suppress unnecessary discharge of the cleaning liquid.

The coating apparatus 10 of this embodiment includes a first optical fiber cable 70A for light emitting having a first light emitting unit 73A at the tip and a first optical fiber cable 70B for light receiving having a first light receiving unit 73B at the tip. , Is equipped. When installing an electronic device including a photoelectric element for receiving and receiving light in a painting booth, it is necessary to make the electronic device an explosion-proof structure so that the paint does not catch fire. However, according to this coating apparatus 10, since the first light emitting section 73A and the first light receiving section 73B are provided at the tip portions of the first optical fiber cables 70A and 70B that do not require energization, the first light emitting section 73A and the first light receiving section 73B are provided. 1 The light receiving portion 73B can be arranged in the painting booth without having an explosion-proof structure.

The first light emitting unit 73A and the first light receiving unit 73B of the coating apparatus 10 of this embodiment are arranged so as to face the flow path 62 in the first block (the flow path outside the coating gun 20 in the common flow path 50). Has been done. As a result, the first light emitting unit 73A and the first light receiving unit 73B can be incorporated into the painting device 10 without changing the structure of the painting gun 20, so that the first light emitting unit 73A and the first light emitting unit 73A and the first light receiving unit 73B can be incorporated into the painting device 10. 1 The light receiving unit 73B can be easily mounted.

Further, the painting apparatus 10 of the present embodiment includes a painting gun 20, a plurality of paint supply sources 30, a switching valve 38 for switching the type of paint supplied toward the painting gun 20, and an outlet 39 of the switching valve 38 for painting. The second light projecting unit 93A arranged so as to face the common flow path 50 connecting the discharge port 24 of the gun 20 and the light projected from the second light projecting unit 93A and reflected by the fluid in the common flow path 50 are received. A second light receiving unit 93B is provided, and based on the reflected light received by the second light receiving unit 93B, it is determined whether or not the filling of the desired type of paint in the common flow path 50 is completed. In this coating apparatus 10, when cleaning is completed and new paint is supplied, the new paint is discharged while being mixed with the cleaning liquid remaining in the common flow path 50, and the ratio of the cleaning liquid in the common flow path 50 is While it gradually decreases, the proportion of the paint in the common flow path 50 gradually increases. Then, when the entire inside of the common flow path 50 is filled with the paint, the second light receiving unit 93B receives the light reflected by the paint filled in the common flow path 50. Based on the reflected light, it is possible to detect whether or not the reflective material is a desired type of paint, so that the filling of the paint is completed at the timing when the inside of the common flow path 50 is filled with the new paint. It can be determined, and as a result, wasteful ejection of the paint can be suppressed.

The coating apparatus 10 of this embodiment includes a second optical fiber cable 90 having a second light emitting unit 93A and a second light receiving unit 93B at the tip thereof. When an electronic device including a photoelectric element for receiving and receiving light is placed in a painting booth, it is necessary to make the electronic device an explosion-proof structure so that the paint does not catch fire. However, according to this coating apparatus 10, since the second light emitting section 93A and the second light receiving section 93B are provided at the tip of the second optical fiber cable 90 that does not require energization, the second light emitting section 93A and the second light receiving section 93B are provided. The portion 93 can be arranged in the painting booth without having an explosion-proof structure.

The second light projecting unit 93A of the painting device 10 of this embodiment projects light toward the paint in the flow path outside the painting gun 20 in the common flow path 50. As a result, the second light emitting section 93A and the second light receiving section 93B can be incorporated into the painting device 10 without changing the structure of the painting gun 20, so that the second light emitting section 93A and the second light receiving section 93B can be incorporated into the painting device 10. The light receiving unit 93B can be easily mounted.

<Other Examples>
The present invention is not limited to the examples described in the above description and drawings, and for example, the following examples are also included in the technical scope of the present invention.
(1) In the first embodiment, the second light emitting element is a white LED, but a light emitting element other than the LED may be used as long as it emits light that can identify the type (for example, color) of the reflecting object. However, it may be a light emitting color other than white. For example, the light emitting element may be a red LED, a green LED, and a blue LED.
(2) In the first embodiment, the second light receiving element receives the white light reflected by the reflecting object without dispersing it. However, it is provided with a spectroscopic unit that disperses the white light reflected by the reflecting object through a prism, and the three photodiodes constituting the second light receiving element emit the spectroscopic light (red light, green light, and blue light). The light may be received individually.
(3) In the first embodiment, the first optical fiber cable and the second optical fiber cable are fixed to separate blocks, but they may be fixed to the same block. In this case, only one block is required. For example, by using the first block, the second optical fiber cable can be arranged so as to face the third flow path of the flow path in the first block.
(4) In the first embodiment, the first accommodating portion and the second accommodating portion communicate with the common flow path, but they may not communicate with each other. In this case, it is necessary to form a transparent member between the common flow path and the first accommodating portion and the second accommodating portion. For example, the hose forming the common flow path needs to be made of a transparent member.
(5) In the first embodiment, the first optical fiber cable and the second optical fiber cable are installed by fitting them into the accommodating portion of the member (first block or second block) forming the common flow path. However, another installation method may be adopted. For example, the transparent hose forming the common flow path may be fixed with a fixing tool or the like.
(6) In the first embodiment, it is determined whether or not the cleaning in the common flow path is completed based on the transmitted light in the state where the supply of the cleaning liquid and the air is stopped. However, it may be determined whether or not the cleaning in the common flow path is completed based on the transmitted light in the state where the cleaning liquid or air is supplied.
(7) In Example 1 above, a coating device for spray painting using a solvent-based paint has been described, but it can also be applied to a painting device for painting using a non-solvent paint, and painting other than spray painting can be performed. It can also be applied to painting equipment.
(8) In Example 1 above, the first block and the second block are made of aluminum, but they may be made of different materials, for example, they may be made of a metal other than aluminum, or they may be made of synthetic resin. You may. When the first block and the second block are made of a member having an insulating property, it is necessary to coat the inner wall surface of the flow path in the first block or the flow path in the second block with a resin having an insulating property. There is no.

10 ... Painting device 20 ... Painting gun 24 ... Discharge port 30 ... Paint supply source 34 ... Cleaning liquid supply source 36 ... Air supply source 38 ... Switching valve 39 ... Outlet 50 ... Shared flow path 70 ... First optical fiber cable 70A ... Floodlight 1st optical fiber cable 70B ... 1st optical fiber cable 73A for light receiving ... 1st light projecting unit 73B ... 1st light receiving unit 90 ... 2nd optical fiber cable (optical fiber cable)
93A ... 2nd floodlight section (floodlight section)
93B ... Second light receiving part (light receiving part)
100 ... Control unit 114 ... Cleaning determination unit 124 ... Filling determination unit A1 ... Explosion-proof area A2 ... Non-explosion-proof area

Claims (2)

With a paint gun,
Multiple paint sources that individually supply different types of paint to the paint gun,
A switching valve provided between the paint gun and the plurality of paint supply sources to switch the type of paint supplied to the paint gun.
A cleaning liquid supply source connected to the switching valve via the cleaning liquid supply path and supplying the cleaning liquid toward the coating gun, and a cleaning liquid supply source.
A first light emitting unit, a first light receiving unit, and a second light emitting unit arranged so as to face the common flow path from the outlet of the switching bulb to the discharge port of the coating gun.
A second light receiving unit that receives light that is projected from the second light projecting unit and reflected by the fluid in the common flow path.
A cleaning determination for determining whether or not the cleaning in the common flow path is completed based on the amount of light projected from the first light projecting section, passing through the common flow path, and received by the first light receiving section. Department and
A filling determination unit that determines whether or not the filling of a desired type of paint in the common flow path is completed based on the reflected light received by the second light receiving unit.
A first optical fiber cable having the first light emitting part and the first light receiving part at the tip thereof,
A second optical fiber cable having the second light emitting portion and the second light receiving portion at the tip thereof, and the tip portion is arranged so as to face the same direction as the traveling direction of the paint in the common flow path.
Equipped with
A coating apparatus characterized in that when it is determined by the cleaning determination unit that cleaning in the common flow path is completed, a process of supplying new paint is performed. The coating according to claim 1, wherein the second light projecting portion is arranged so as to face the flow path from the outlet of the switching valve to the supply port of the coating gun among the common flow paths. Device.

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