JP2008212801A - Coating material supply apparatus and method of recovering coating material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating material supply apparatus which can be made small in size, low in pressure and short in a period of time needed for a color change process, and is excellent in cleaning property. <P>SOLUTION: The coating material supply apparatus has a coating material tank 61 formed into a hermetically closed space and housing a coating material 2 to supply a coating material to a coating material pipe line 50, a pressurized air source for supplying pressurized air to the hermetically closed space of the coating material tank, an air pipe line for connecting the pressurized air source to the hermetically closed space of the coating material tank and a three-way valve 62 provided in the middle of the air pipe line to supply the pressurized air supplied from the pressurized air source to the hermetically closed space of the coating tank in a first position and to reduce the pressure of the hermetically closed space of the coating material tank in second position. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a paint supply apparatus capable of collecting paint in a paint tank when a paint color is switched in a paint line of an automobile or the like, and a paint collection method for collecting residual paint in the paint tank.

  The paint supply device used in the painting line of automobiles, etc. is a paint tank that is filled with paint of each color, a pump that pumps it, and a paint that guides the paint from the paint tank to the coating machine through the color change valve unit As many paint tanks, pumps, and paint pipes as the number of paint colors are provided. And the paint of the coating color according to a vehicle specification is sprayed by switching the color change valve unit provided in the upstream of the coating machine.

  By the way, a common circulation pipe is provided for a plurality of paint color specifications, and a forecolor paint remaining in the paint pipe is collected by passing a movable member (free piston) called a pig through the paint pipe. This has also been proposed (see, for example, Patent Document 1).

  In such a paint supply device using a pig, for example, when the paint in the circulation pipe is collected and the cleaning liquid is circulated, or when the paint of the next color is circulated after washing the circulation pipe, the pig is retracted from the circulation pipe. In addition to the circulation piping, a dedicated piping is required to clean the pig itself. For this reason, the paint supply apparatus is increased in size and pressure, and the paint collecting operation and the piping / pig cleaning operation are inefficient.

JP 2002-126608 A

The problem to be solved by the present invention is to provide a paint supply apparatus and a paint recovery method that are excellent in detergency and that can reduce the time required for downsizing, reducing the pressure and changing the color of the paint supply apparatus.

1st invention is provided with the paint piping in which the pig was inserted so that reciprocation was possible along an axial direction, and the 1st and 2nd pig landing part connected to the edge part of paint piping, respectively, The 1st pig landing part This is a paint supply device capable of collecting the paint remaining in the paint pipe by supplying a fluid for extrusion from the side and moving the pig to the second pig landing part via the paint pipe.

  In the paint supply apparatus according to the present invention, at least one of the first and second pig landing parts is connected to the paint pipe, a main passage through which the pig can enter, a pig receiving surface that prevents the pig from moving, And at least two sub passages communicating with the main passage, and the pig abuts the pig receiving surface, so that the pig blocks one of the at least two sub passages.

A paint tank that contains paint and forms a sealed space, supplies paint to the paint pipe, a pressurized air source that is connected to the sealed space of the paint tank and supplies pressurized air, and a pressurized air source And an air pipe connecting the sealed space of the paint tank, and a pressurized air supplied from a pressurized air source at the first position to the sealed space of the paint tank. And a three-way valve for reducing the pressure in the sealed space of the paint tank in the position.

In the second invention, the pig inserted into the paint pipe is moved from the second pig landing part side to the first pig landing part side through the paint pipe by supplying the paint, and in this state to the object to be coated. The coating step for applying the paint, and the pig is supplied to the first pig landing part side through the extrusion fluid and moved to the second pig landing part via the paint pipe, so that the paint remaining in the paint pipe is removed. A paint recovery method comprising a recovery step of recovering to a paint tank and a cleaning step of supplying a cleaning fluid into the paint pipe and cleaning the paint pipe after recovering the paint into the paint pipe.

  In the paint recovery method according to the present invention, in the first or second pig landing part, the paint pipe is washed while the paint pipe is connected and the pig is held in the main passage through which the pig can enter. .

In the painting step, the pressurized air is supplied to the sealed space of the paint tank having a sealed space to supply the paint contained in the paint tank to the paint pipe, and in the collecting step, the sealed space of the paint tank The paint remaining in the paint pipe in a state where the pressure is reduced is recovered to the paint pipe.

  In the present invention, the pig seals one of at least two sub-passages by the pig coming into contact with the pig receiving surface. Therefore, in the second pig landing part on the paint tank side, the sub-passage connected to the paint tank is blocked by the pig, and the sub-passage that is not blocked by the pig while the pig is held in the main passage Can be used to clean the inside of the paint piping.

Also, in the first pig landing part on the coating machine side, the secondary passage not connected to the coating machine is blocked by the pig, and the secondary passage that is not blocked by the pig is kept in the state where the pig is held in the main passage. It can be used to supply paint to the coating machine.

Therefore, there is no need for a dedicated pipe for evacuating the pig from the paint pipe when cleaning the paint pipe or supplying the paint. Excellent cleaning properties.

  When painting, pressurized air is supplied to the sealed space of the paint tank, while when the paint remaining in the paint pipe is recovered to the paint tank, the sealed space of the paint tank is decompressed using a three-way valve. As a result, the paint is collected smoothly.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram showing the overall configuration of a paint supply apparatus according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing a receiving pig station of the paint supply apparatus according to the embodiment, and FIGS. FIG. 4 is a cross-sectional view showing a feed-side pig station of a paint supply apparatus according to the present embodiment, and FIG. 5 is a schematic plan view showing a coating system according to the present embodiment. .

  As shown in FIG. 1, the coating material supply apparatus 10 which concerns on embodiment of this invention is the coating material supplied to the coating gun 2 comprised, for example from a rotary atomization type electrostatic coating machine or an air atomization type electrostatic coating machine. The main color change valve unit 20 (hereinafter referred to as the main CCV 20) for selecting from among various types of paints, and the paint supplied from the main CCV 20 is guided to the coating gun 2.

  The main CCV 20 includes a manifold 21, a first three-way valve 22, and a switching valve (not shown), and a first port 221 of the first three-way valve 22 is connected to the manifold 21. The second port 222 of the three-way valve 22 is connected to a receiving-side pig station 30 (described later) so that paint is supplied, and the third port 223 of the three-way valve 22 releases pressure or drains liquid. Is connected to a first dump valve 23.

In the main CCV 20, the paint is supplied into the manifold 21 by selecting one of the first three-way valve 22 and a switching valve (not shown), and a trigger valve (not shown) is further provided in the paint gun 2. By opening, the paint is discharged to the object. The first three-way valve 22 and the switching valve open and close based on a control signal (air signal) from a control device (not shown).

  Incidentally, in FIG. 1, only the first three-way valve 22 of this example is shown, and other switching valves are omitted, but this switching valve may be configured in the same manner as the first three-way valve 22 of this example. Alternatively, the main supply pipe may be directly connected from the paint tank. In the following description, the present invention will be described on behalf of the first three-way valve 22 shown for convenience.

  As shown in FIG. 1, the first three-way valve 22 is connected to the receiving pig station 30 via a paint hose so that the second port 222 communicates with a passage 32a formed in the first sensor base 32. Yes. As shown in FIG. 2, the first sensor base 32 is fixed to the station main body 31 of the receiving pig station 30, and a passage 32 a of the first sensor base 32 is formed inside the station main body 31. It communicates with the auxiliary passage 31b. The first pressure sensor 33 is fixed to the first sensor base 32 so that the pressure-sensitive surface 33a faces the passage 32a.

  As shown in FIG. 1, the first pressure sensor 33 is connected to the determination device 70 via a cable so that the detection result can be transmitted. The determination device 70 includes a CPU and the like, and determines the position of the pig 90 based on the detection results of the first and second pressure sensors 33 and 44. A specific determination method by the determination device 70 will be described later.

  The position of the pig 90 determined by the determination device 70 is displayed on the notification device 80 including a monitor or the like. Further, the notification device 80 notifies the trouble information such that the pig 90 does not exist at the predetermined position.

  As shown in FIG. 2, the first sub passage 31 b of the station main body 31 is a passage branched from the main passage 31 a formed in the station main body 31. At one end of the main passage 31a, one end of the paint hose 50 into which the pig 90 is inserted so as to be able to reciprocate is fixed by a cap 31c, and the inner hole of the paint hose 50 and the station body 31 main passages 31a communicate with each other.

  Here, as shown in FIGS. 3A and 3B, the pig 90 according to the present embodiment has a substantially cylindrical shape with two diameters in the vicinity of both ends, and the pig receiving surfaces of the pig stations 30 and 40 described later. 34b, 462b and a cylindrical first seal portion 91 that seals the second sub passages 34a, 462c, and an abacus ball-shaped second seal portion 92 that is in close contact with the inner wall surface of the paint hose 50.

  The first seal portion 91 is constituted by both end surfaces of the pig 90, and the circular edge portions thereof are in close contact with the pig receiving surfaces 34b and 462b, respectively, thereby sealing the second sub passages 34a and 462c.

  On the other hand, the second seal portion 92 is configured from a portion whose diameter is increased in the pig 90. The outer diameter D1 of the second seal portion 92 is substantially the same as or slightly larger than the inner diameter D2 (see FIG. 2) of the paint hose 50 (D2 ≦ D1), and the pig 90 moves in the paint hose 50. Thus, the second seal portion 92 scrapes off the paint remaining in the paint hose 50. The outer diameter D1 of the second seal portion 92 is such that the pig 90 can move smoothly in the paint hose 50 and that the paint does not leak from the gap between the second seal portion 92 and the inner wall of the paint hose 50. Has been.

  In the pig 90 of this example, the first seal portion 91 and the second seal portion 92 are provided in different parts, so that the wear of the seal portions 91 and 92 is dispersed, thereby extending the life of the pig 90. it can.

  As shown in FIG. 2, the main passage 31a of the station body 31 has an inner diameter D3 that is relatively larger than the outer diameter D1 of the pig 90 (D3> D1), and holds the pig 90 in the main passage 31a. In this state, the fluid can be circulated in the main passage 31a. That is, a gap is formed between the second seal portion 92 of the pig 90 and the inner wall of the main passage 31a to allow fluid to pass smoothly.

  As shown in FIG. 2, a manifold 34 is fixed to the other end of the station main body 31, and a main passage 31 a of the station main body 31 communicates with a second sub passage 34 a formed in the manifold 34. is doing. The inner diameter D4 of the second sub passage 34a is relatively smaller than the inner diameter D3 of the main passage 31a (D4 <D3), and is relatively smaller than the outer diameter D7 of the first seal portion 91 of the pig 90. (D4 <D7).

Further, a pig receiving surface 34 b for stopping the pig 90 that has moved to the receiving side pig station 30 through the paint hose 50 comes into contact is formed by an end surface of the manifold 34 on the station main body 31 side. In the present embodiment, the pig receiving surface 34b is formed in a concave spherical shape formed around the opening of the second sub passage 34a.

  Since the pig receiving surface 34b has a spherical shape and the first seal portion 91 of the pig 90 has a circular edge, the second sub-passage 34a regardless of the contact angle of the pig 90 with respect to the pig receiving surface 34b. Can be surely sealed. That is, the circular edge closely contacts the spherical inner wall geometrically at any angle.

As a result, in this embodiment, since the pressure accurately fluctuates in the piping system, it is possible to detect the pig position using an explosion-proof pressure sensor instead of the conventional pig position detection using the magnet embedded in the pig 90. Thus, the cost of the paint supply device can be reduced and the structure of the device can be simplified.

  Returning to FIG. 1, the manifold 34 fixed to the other end of the station main body 31 includes a first cleaning liquid supply valve 35 a capable of supplying a cleaning liquid, and a first air supply valve 35 b capable of supplying pressurized air. A second dump valve 35c is provided for waste liquid outside. Each valve 35a-35c can be opened and closed by a control signal (air signal) from a control device (not shown).

  On the other hand, as shown in FIGS. 1 and 4, one end of the station main body 41 of the feeding-side pig station 40 is fixed to the other end of the paint hose 50 by a cap 41d. The hole communicates with a main passage 41a formed in the station main body 41. The main passage 41a has an inner diameter D5 that is relatively larger than the outer diameter D1 of the pig 90 (D5> D1), and the main passage 41a is held in the main passage 41a with the pig 90 held in the main passage 41a. The fluid can be circulated.

  As shown in FIG. 4, a second sensor base 43 is fixed to the station body 41, and a passage 43a formed in the second sensor base 43 communicates with a first sub-passage 41b branched from the main passage 41a. . The second pressure sensor 44 is fixed to the second sensor base 43 so that the pressure-sensitive surface 44a faces the passage 43a. Similar to the first pressure sensor 33 described above, the second pressure sensor 44 is connected to the determination device 70 via a cable so that the detection result can be transmitted. In addition, as shown in FIG. 1, a third dump valve 45 for draining liquid to the outside is connected to the passage 43 a of the second sensor base 43.

  Returning to FIG. 4, in the present embodiment, a stopper 42 composed of, for example, an air cylinder is fixed to the station main body 41, and the stopper pin 42 a is the main through a through hole 41 c formed on the side surface of the station main body 41. It is possible to move forward and backward in the passage 41a. When the stopper pin 42a advances into the main passage 41a, the movement of the pig 90 is blocked. On the other hand, when the stopper pin 42a retracts from the main passage 41a, the pig 90 can be moved.

  An attachment / detachment portion 46 for taking out the pig 90 from the sending-side pig station 40 is fixed to the other end portion of the station main body 41. As shown in the figure, the attaching / detaching portion 46 is fixed to a first attaching / detaching member 461 fixed to the station main body 41 and an end portion of a sub color change valve unit 47 (hereinafter referred to as sub CCV 47). 2 detachable members 462 and a clamp 463 for connecting the first detachable member 461 and the second detachable member 462.

  The first detachable member 461 has a disk shape having a flange portion 461a, and a passage 461b having the same inner diameter D5 as the main passage 41a of the station body 41 is formed at the center thereof. The first attaching / detaching member 46a is fixed to the station body 41 so that the main passage 41a and the passage 461b communicate with each other.

  Similarly, the second detachable member 462 has a disk shape having a flange portion 462a, and a second auxiliary passage 462c is formed at the center thereof. The inner diameter D6 of the second sub-passage 462c is relatively smaller than the inner diameter D5 of the main passage 41a (D6 <D5), and is relatively smaller than the outer diameter D7 of the first seal portion 91 of the pig 90. (D6 <D7).

In addition, the pig receiving surface 462b for the pig 90 that has moved to the feeding-side pig station 40 through the paint hose 50 to come into contact and stop is constituted by the end surface of the second detachable member 462 that faces the first detachable member 461. Has been. In the present embodiment, the pig receiving surface 462b has a concave spherical shape formed around the opening of the second sub-passage 462c, like the above-described pig receiving surface 34b.

  Since the pig receiving surface 462b has a spherical shape and the first seal portion 91 of the pig 90 has a circular edge, the second sub-passage 462c is formed regardless of the contact angle of the pig 90 with respect to the pig receiving surface 462b. Can be surely sealed. That is, the circular edge closely contacts the spherical inner wall geometrically at any angle.

As a result, in this embodiment, since the pressure accurately fluctuates in the piping system, it is possible to detect the pig position using an explosion-proof pressure sensor instead of the conventional pig position detection using the magnet embedded in the pig. In addition, the cost of the paint supply device can be reduced, and the device structure can be simplified.

  The first attaching / detaching member 461 and the second attaching / detaching member 462 include the flange portions 461a in a state where the positioning pins 462d of the second attaching / detaching member 462 are inserted into the positioning holes 461c of the first attaching / detaching member 461 and are in close contact with each other. , 462a are detachably connected by a one-touch operation. In the state of being connected in this way, the passage 461b of the first attachment / detachment member 461 and the second sub passage 462b of the second attachment / detachment member 462 communicate with each other, and the end point of the passage 461b of the first attachment / detachment member 461 is 2 The pig receiving surface 462b formed in the detachable member 462 is located.

  Returning to FIG. 1, the sub-CCV 47 includes a manifold 48 fixed to the detachable portion 46 and first to fifth switching valves 49 a to 49 e to which the paint is supplied from the paint tank 61. By selecting the switching valves 49 a to 49 e, the paint is supplied to the passage 48 a formed in the manifold 48. Further, as shown in FIG. 4, the passage 48 a communicates with the second sub passage 462 c of the attaching / detaching portion 46, and the paint is supplied from the sub CCV 47 to the main passage 41 a via the attaching / detaching portion 46.

  As shown in FIG. 1, the sub-CCV 47 includes a second cleaning liquid supply valve 49f capable of supplying a cleaning liquid, a second air supply valve 49g capable of supplying pressurized air, and a fourth liquid waste to the outside. A dump valve 49h is further provided. Each of the valves 49a to 49h is opened and closed by a control signal (air signal) from a control device (not shown).

  The paint P supplied to the first to fifth switching valves 49a to 49e is housed in a sealed paint tank 61, to which the first port 621 of the second three-way valve 62 is connected. Yes. In addition, pressurized air from a pressurized air source is supplied to the second port 622 of the second three-way valve 62. In addition, an open / close valve is provided in an air pipe from a pressurized air source (not shown), and supply of pressurized air from the pressurized air source is stopped when the paint is collected.

Furthermore, the pressurized air in the paint tank 61 can be released to the atmosphere via the third port 623 of the second three-way valve 62.

By closing the third port 623, pressurized air is supplied from the second port 622 to the sealed paint tank 61, and the paint P is pumped toward the first switching valve 49 a through the paint pipe 63.

On the other hand, by opening the third port 623 and stopping the supply of pressurized air from the pressurized air source, the pressurized air in the paint tank 61 that has been pressurized is released to the atmosphere. The paint can be collected from the hose 50 toward the paint tank 61.

In FIG. 1, the paint tank 61 and the second three-way valve 62 are connected only to the first switching valve 49a, but actually, the second to fifth switching valves 49b to 49e are different paints. A paint tank 61n containing Pn and a second three-way valve 62n are connected.

Moreover, it is not particularly limited in the present invention, pressurized air is sent into the paint tank 61, than typical pressure 5 kg / cm ² is low, also be applied to paint specifications of a few kg / cm ² for example Can do.

  As shown in FIG. 5, the coating material supply apparatus 10 configured as described above is provided for each of a plurality of painting robots 4 provided in the painting booth B, for example, and constitutes a painting system. A coating gun 2 is provided as an end effector at the tip of the coating robot 4, and each color paint can be supplied to the paint gun 2 from the paint supply device 10.

  In the present invention, the present invention is not limited to the coating system as described above. For example, one paint supply device 10 may be assigned to a plurality of painting robots 4.

  Next, the paint recovery method according to the present embodiment will be described according to the color change procedure of the paint supply apparatus 10.

  FIG. 6 is a flowchart showing the paint recovery method according to the present embodiment, FIGS. 7A to 7F are block diagrams showing the state of the paint supply device in each step shown in FIG. 6, and FIGS. FIG. 9 is a cross-sectional view showing a layer structure of an extruding fluid during paint recovery.

  First, as shown in FIG. 7A, a state (step S10 in FIG. 6) in which the paint supply device 10 is supplying the paint of the previous color (the paint P contained in the paint tank 61) to the paint gun 2 will be described. . In the initial state, the pig 90 is positioned in the feeding-side pig station 40, the stopper pin 42a of the stopper 42 is retracted from the main passage 41a, and all the valves are closed.

In such a state, since the third port 623 of the second three-way valve 62 is closed, pressurized air is introduced into the paint tank 61 via the second port 622 of the second three-way valve 62, and the paint tank The inside of 61 is pressurized. The applied pressure in the sealed paint tank 61 becomes the paint discharge pressure.

Here, when the first switching valve 49 a of the sub CCV 47 is opened and the second dump valve 35 c is opened, the paint P in the paint tank 61 is transferred from the passage 48 a of the manifold 48 to the second sub-passage 462 c of the second attachment / detachment member 462. → The passage 461b of the first detachable member 461 → the main passage 41a of the station main body 41 → the paint hose 50 and the receiving side pig station 30. During this time, the pig 90 is pressure-fed from the feed-side pig station 40 to the receiving-side pig station 30 via the paint hose 50 (pressed by the paint P from the back), and comes into contact with the pig receiving surface 34b of the receive-side pig station 30. Stop. The reason why the second dump valve 35c is opened in step S10 is that the passage through which the paint P flows is opened to the atmosphere so that the paint can be smoothly pumped even at a low pressure.

By contact between the first seal portion 91 of the pig 90 and the pig receiving surface 34b, as shown in FIG. 8A, the second sub-passage 34a is blocked, and the flow path to the second dump valve 35c is automatically shut off. Is done. In the present embodiment, since the pig receiving surface 34b has a spherical shape and the first seal portion 91 of the pig 90 has a circular edge, as shown in FIG. Even if the pig 90 abuts against the surface 34b at an angle, the second sub-passage 34a can be reliably sealed.

  At this time, the determination device 70 compares the pressure P1 detected by the first pressure sensor 33 with the pressure P2 detected by the second pressure sensor 44. When these pressures P1 and P2 are substantially the same (P1 = P2), the determination device 70 determines that the pig 90 has moved to the receiving pig station 30.

  On the other hand, when the predetermined time has passed in a state where the pressures P1 and P2 are not the same (P1 ≠ P2), the determination device 70 determines that the pig 90 has not moved to the receiving pig station 30; The notification device 80 notifies the defect information.

This is due to the following reason. That is, the second pressure sensor 44 detects that the paint hose 50 is moving from the feed-side pig station 40 toward the receiving-side pig station 30 while the pig 90 is pushed by the paint P pushed out of the paint tank 61. While the applied pressure P2 becomes the paint pressure, the pressure P1 detected by the first pressure sensor 33 becomes the atmospheric pressure. Therefore, if the paint pressure (that is, the pressure of the pressurized air) is set to several kg / cm ^2. As long as the pig 90 moves normally, P1 <P2. When the pig 90 normally arrives at the receiving pig station 30, the pressure P2 detected by the second pressure sensor 44 maintains the paint pressure, while the pressure P1 detected by the first pressure sensor 33 is also the paint pressure. Therefore, P1 = P2.

  When it is detected that the pig 90 has moved to the receiving-side pig station 30 in this way, the first dump valve 23 is opened to the atmosphere for a predetermined time. The paint P reaching the main passage 31a of the station main body 31 due to the release of the atmosphere reaches the passage 32a in the first sensor base 32 → the paint hose → the second port 222 of the first three-way valve 22 of the main CCV 20 and the paint P Is filled in the first three-way valve 22, and the preparation for painting is completed. Then, when it is time to paint the paint P stored in the paint tank 61, the first three-way valve 22 is opened and the paint is supplied to the paint gun 2.

  When the painting operation is completed and a different paint is applied, the color changing operation of the paint supply device 10 is performed according to the following procedure.

  First, as shown in step S <b> 20 of FIG. 6, the paint that has been applied is collected in the paint tank 61. Based on the signal indicating the completion of the coating of the previous color paint, the second dump valve 35c is closed, and the third port 622 of the second three-way valve 62 is opened to the atmosphere (at the same time, the supply of pressurized air is stopped). Release the pressure in the tank 61.

Then, the first cleaning liquid supply valve 35 a or the first air supply valve 35 b of the receiving side pig station 30 is opened to supply cleaning liquid or pressurized air, and the pig 90 located in the receiving side pig station 30 is located. Is sent back to the feeding-side pig station 40, and the paint filled in the paint hose 50 is collected into the paint tank 61.

At this time, the pig 90 stops by coming into contact with the pig receiving surface 462b of the feeding-side pig station 40. Due to the contact between the first seal portion 91 of the pig 90 and the pig receiving surface 462b, the second sub passage 462c is blocked, and the flow path to the sub CCV 47 is automatically blocked.

  At this time, the determination device compares the pressure P1 detected by the first pressure sensor 33 with the pressure P2 detected by the second pressure sensor 44. When these pressures P1 and P2 are substantially the same (P1 = P2), the determination device 70 determines that the pig 90 has moved to the feeding-side pig station 40. Etc., the position of the pig 90 is displayed.

  On the other hand, when the predetermined time has passed in the state where the pressures P1 and P2 are not the same (P1 ≠ P2), the determination device 70 determines that the pig 90 has not moved to the feeding-side pig station 40, The notification device 80 notifies the defect information via a monitor or the like.

This is due to the following reason. That is, the pressure P1 detected by the first pressure sensor 33 while the paint hose 50 is moving from the receiving-side pig station 30 toward the feeding-side pig station 40 in a state where the pig 90 is pushed by the cleaning liquid or pressurized air. Is the pressure of the cleaning liquid or pressurized air, while the pressure P2 detected by the second pressure sensor 44 is the pressure of the residual paint, that is, atmospheric pressure. If so, P1> P2 as long as the pig 90 moves normally. When the pig 90 normally arrives at the sending-side pig station 40, the pressure P1 detected by the first pressure sensor 33 maintains the cleaning liquid or the pressurized air pressure, while the pressure detected by the second pressure sensor 44. Since P2 is also a cleaning liquid or a pressurized air pressure, P1 = P2.

  As the cleaning liquid supplied through the first cleaning liquid supply valve 35a, thinner can be used when the paint is an organic solvent-based paint, and water is used when the paint is a water-based paint. Can do.

  In the above-described embodiment, when the paint P is pushed back through the pig 90, the cleaning liquid or air supplied from the first cleaning liquid supply valve 35a or the first air supply valve 35b is used as the extrusion fluid. Although described, it is not particularly limited in the present invention, and the following extrusion fluid 100 may be used.

  For example, as shown in FIG. 9, the extrusion fluid 100 for pushing back (recovering) the paint P filled in the paint hose 50 to the paint tank 61 via the pig 90 is a first composed of air. Layer 101 and a second layer 102 made of a solvent, and the first layer 101 is interposed between the second layer 102 and the pig 90. By supplying pressurized air from the first air supply valve 35b to form the first layer 101, and then supplying the cleaning liquid from the first cleaning liquid supply valve 35a to form the second layer 102, This extrusion fluid 100 can be configured. The length L along the axial direction of the first layer 101 in the paint hose 50 is preferably about 10 to 30 mm depending on the inner diameter and length of the paint hose 50. In addition, you may comprise the 1st layer 101 with the solvent and dilution solvent which are contained in the coating material.

  The first layer 101 of the extrusion fluid 100 can prevent the cleaning liquid from being mixed into the coating material, and can stabilize the quality of the coating material. Further, the second layer 102 of the extruding fluid 100 can reduce the amount of compression of the extruding fluid 100 at the time of collecting the paint, and can stably operate the apparatus.

  When it is detected that the pig 90 has moved to the feeding-side pig station 40, as shown in FIG. 7B, the third dump valve 45 is opened and the first cleaning liquid supply valve 35a is opened to supply the cleaning liquid (FIG. 6). Step S30). As a result, the path extending from the second sub-passage 34 a in the manifold 34 → the main passage 31 a in the station body 31 → the paint hose 50 → the main passage 41 a in the station body 41 → the passage 43 a in the second sensor base 43 is washed. The

  In addition, since the pig 90 is held in the main passage 31a of the station main body 41 at the time of this step S30, the front end of the pig 90 mainly on the receiving pig station 30 side (the right side of the figure) ) Is washed. Further, since the cleaning liquid also passes through the passage 43a of the second sensor base 43, the pressure sensitive surface 44a of the second pressure sensor 44 is cleaned.

  Next, as shown in FIG. 7C, the stopper 42 is operated to move the stopper pin 42a into the main passage 41a, and the first cleaning liquid supply valve 35a is closed. In this state, the second cleaning liquid supply valve is closed. 49f is opened and the cleaning liquid is supplied (step S40 in FIG. 6). Accordingly, the passage 48a of the manifold 48 of the sub CCV 47 → the second sub passage 462c of the second attachment / detachment member 462 → the passage 461b of the first attachment / detachment member 461 → the main passage 41a of the station body 41 → the passage 43a of the second sensor base 43. The route to reach is cleaned with a cleaning solution. Further, at the time of this step S40, since the movement of the pig 90 to the receiving-side pig station 30 side is restricted by the stopper 42, the rear end portion (left side in the figure) of the pig 90 is mainly washed.

  As the cleaning liquid supplied through the second cleaning liquid supply valve 49f, thinner can be used when the paint is an organic solvent-based paint, and water is used when the paint is a water-based paint. Can do.

  Next, as shown in FIG. 7D, the third dump valve 45 is closed and the first dump valve 23 is opened. In this state, the second cleaning liquid supply valve 49f is opened to supply the cleaning liquid (step of FIG. 6). S50). Accordingly, the passage 48a of the manifold 48 of the sub CCV 47 → the second auxiliary passage 462c of the second attachment / detachment member 462 → the passage 461b of the first attachment / detachment member 461 → the main passage 41a of the station main body 41 → the paint hose 50 → the main of the station main body 31. The flow path from the passage 31a to the passage 33a of the first sensor base 33 to the first three-way valve 22 is cleaned with the cleaning liquid.

  At this time, the pig 90 is held in the main passage 41a of the feed-side pig station 40 by the stopper 42, and the outer diameter D1 thereof is relatively smaller than the inner diameter D5 of the main passage 41a. Since the cleaning liquid passes through the periphery of the pipe 90, the pig 90 is more reliably cleaned.

  Next, as shown in FIG. 7E, the first dump valve 23 is closed and the second dump valve 35c is opened. In this state, the second cleaning liquid supply valve 49f is opened to supply the cleaning liquid (step of FIG. 6). S60). Accordingly, the passage 48a of the manifold 48 of the sub CCV 47 → the second auxiliary passage 462c of the second attachment / detachment member 462 → the passage 461b of the first attachment / detachment member 461 → the main passage 41a of the station main body 41 → the paint hose 50 → the main of the station main body 31. The path from the passage 31a to the second sub passage 34a of the manifold 34 is cleaned with the cleaning liquid.

  Next, as shown in FIG. 7F, the second dump valve 35c and the second cleaning liquid supply valve 49f are closed, and the fourth dump valve 49h and the first air supply valve 35b are opened to supply air (FIG. 6). Step S70). As a result, the cleaning liquid remaining in the flow path is discarded from the fourth dump valve 49h, and at the same time, the pig 90 regulated by the stopper 42 moves toward the pig receiving surface 462b of the feeding side pig station 40. To do. Next, the fourth dump valve 49h and the first air supply valve 35b are closed, and the stopper pin 42a is retracted from the main passage 41a, whereby the coating material supply apparatus 10 is returned to the initial state.

  The color change operation is completed through the above steps S20 to S70, and the paint supply device 10 can be filled with the next color paint.

  As described above, in the present embodiment, in the receiving-side pig station 30, the pig 90 abuts against the pig receiving surface 34 b, thereby blocking the second sub-passage 34 a not connected to the coating gun 2. The paint can be supplied to the coating gun 2 using the first sub-passage 31b that is not blocked by the pig 90 while being held in the passage 31a.

  Further, in the feeding-side pig station 40, the pig 90 abuts against the pig receiving surface 462b, so that the second sub passage 462c connected to the paint tank 61 is blocked by the pig 90, and the pig 90 is placed in the main passage 41a. The inside of the paint hose 50 can be cleaned using the first sub-passage 41b that is not sealed by the pig 90.

  Therefore, there is no need for a dedicated pipe for retracting the pig 90 from the paint hose 50 or the pig stations 30 and 40 when the paint hose 50 or the pig stations 30 and 40 are washed or when the paint is supplied, and the paint supply apparatus 10 can be downsized. In addition, the time required for color change can be shortened.

  The embodiment described above is described for facilitating the understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  For example, in the above-described embodiment, the pig 90 is cleaned in a state where the pig 90 is held in the feeding-side pig station 40. However, the present invention is not limited to this, and the receiving-side pig station 30 is not limited thereto. A stopper for restricting the movement of the pig 90 may be provided, and the pig 90 may be washed in a state where the pig 90 is held in the receiving-side pig station 30.

It is a block diagram which shows the whole structure of the coating material supply apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the receiving side pig station of the coating material supply apparatus which concerns on embodiment of this invention. It is a side view which shows the pig which concerns on embodiment of this invention. It is a front view which shows the pig which concerns on embodiment of this invention. It is sectional drawing which shows the feed side pig station of the coating material supply apparatus which concerns on embodiment of this invention. It is a schematic plan view which shows the coating system which concerns on embodiment of this invention. It is a flowchart which shows the coating material collection | recovery method which concerns on embodiment of this invention. It is a block diagram which shows the coating material supply apparatus of the state (painting step) which is coating the front color coating material. It is a block diagram which shows the coating material supply apparatus of the state (a collection | recovery step and a 1st washing | cleaning step) which wash | cleans the inside of a coating material supply apparatus after collect | recovering front color coating materials. It is a block diagram which shows the coating material supply apparatus of the state which wash | cleans the inside of a coating material supply apparatus (2nd washing | cleaning step). It is a block diagram which shows the coating material supply apparatus of the state which wash | cleans the inside of a coating material supply apparatus (3rd washing | cleaning step). It is a block diagram which shows the coating material supply apparatus of the state (4th washing | cleaning step) which is cleaning the inside of a coating material supply apparatus. It is a block diagram which shows the coating material supply apparatus of the state (returning step) which has returned the pig to the origin position. It is the schematic which shows the state which the pig contact | abutted in the receiving surface in the pig station. It is a schematic sectional drawing which shows the state which the pig contacted diagonally with the receiving surface in the pig station. It is sectional drawing which shows the layer structure of the fluid for extrusion at the time of paint collection | recovery.

Explanation of symbols

10 ... Paint recovery device 20 ... Main CCV
DESCRIPTION OF SYMBOLS 30 ... Reception side pig station 31 ... Station main body 31a ... Main passage 31b ... 1st subpassage 32 ... 1st sensor base 33 ... 1st pressure sensor 34 ... Manifold 34a ... 2nd subpassage 34b ... Pig receiving surface 40 ... Feeding side Pig station 41 ... Station main body 41a ... Main passage 41b ... First sub passage 42 ... Stopper 43 ... Second sensor base 44 ... Second pressure sensor 46 ... Detachable portion 462b ... Pig receiving surface 462c ... Second sub passage 47 ... Sub CCV
50 ... Paint hose 61 ... Paint tank 62 ... Second three-way valve 90 ... Pig

Claims (17)

A paint pipe inserted so that the pig can reciprocate along the axial direction;
First and second pig landing parts connected to the ends of the paint pipe,
It is possible to collect the paint remaining in the paint pipe by supplying a fluid for extrusion from the first pig landing part side and moving the pig to the second pig landing part via the paint pipe A paint supply device,
At least one of the first and second pig landing portions is connected to the paint pipe, a main passage through which the pig can enter, a pig receiving surface that prevents movement of the pig, and communication with the main passage And at least two secondary passages,
In the paint supply apparatus in which the pig seals one of the at least two sub-passages by the pig coming into contact with the pig receiving surface,
A paint tank that contains paint and is a sealed space, and supplies the paint to the paint pipe;
A pressurized air source connected to the sealed space of the paint tank to supply pressurized air;
An air pipe connecting the pressurized air source and the sealed space of the paint tank;
In the first position, the pressurized air supplied from the pressurized air source is supplied to the sealed space of the paint tank at the first position, and the pressure of the sealed space of the paint tank is set at the second position. A paint supply device comprising a three-way valve for decompressing.   2. The paint according to claim 1, wherein at least one of the first and second pig landing parts includes a regulating unit that regulates movement of the pig toward the second or first pig landing part. Feeding device.   The paint supply apparatus according to claim 1 or 2, wherein the sub-passage blocked by the pig has an inner diameter relatively smaller than a diameter of a contact portion that contacts the pig receiving surface in the pig. . The pig receiving surface is formed in a spherical shape around the opening of the sub-passage sealed by the pig,
The paint supply device according to claim 1, wherein a contact portion that contacts the pig receiving surface of the pig has a circular edge. The pig has a first seal portion that contacts the pig receiving surface and seals the sub-passage, and a second seal portion that closely contacts the inner wall surface of the paint pipe,
The paint supply apparatus according to any one of claims 1 to 4, wherein the first seal part and the second seal part are provided in different parts of the pig. The extrusion fluid has a first layer composed of air or a solvent, and a second layer composed of a cleaning liquid for cleaning the inside of the paint pipe,
The paint supply apparatus according to claim 1, wherein the first layer is interposed between the pig and the second layer in the paint pipe. Detecting means for detecting a pressure in the main passage of at least one of the first or second pig landing parts;
7. A judgment means for judging whether or not the pig is located in the first or second pig landing part based on a detection result of the detection means. The coating material supply apparatus in any one of.   The determination means determines whether the pig is located in the first or second pig landing part based on a pressure difference in the main passage of the first and second pig landing parts detected by the detection means. The paint supply device according to claim 7, wherein the paint supply device is determined. When the pressure in the main passage of the first pig landing part is different from the pressure in the main passage of the second pig landing part, the determination means is that the pig is located in the paint pipe Judgment
When the pressure in the main passage of the first pig landing part and the pressure in the main passage of the second pig landing part are substantially the same, the pig is in the first or second pig landing part. The paint supply apparatus according to claim 8, wherein the paint supply apparatus is determined to be positioned. The pig inserted into the paint pipe is moved from the second pig landing part side to the first pig landing part side by supplying the paint from the second pig landing part side, and in this state, the paint is applied to the object to be coated Painting steps to do,
By supplying an extrusion fluid from the first pig landing part side and moving the pig to the second pig landing part via the paint pipe, the paint remaining in the paint pipe is collected in the paint tank. A recovery step to
A paint recovery method comprising: a cleaning step of supplying a cleaning fluid into the paint pipe and cleaning the paint pipe after the paint is collected in the paint pipe,
In the paint recovery method in which the paint pipe is connected in the first or second pig landing part, and the paint pipe is washed in a state where the pig is held in the main passage into which the pig can enter. ,
In the coating step, supplying the paint contained in the paint tank to the paint pipe by supplying pressurized air to the sealed space of the paint tank having a sealed space,
In the collecting step, the paint remaining in the paint pipe in a state where the sealed space of the paint tank is decompressed is collected into the paint pipe. In the collecting step, the pig blocks one of at least two sub-passages communicating with the main passage of the second pig landing part,
The paint recovery method according to claim 10, wherein in the cleaning step, a cleaning fluid is supplied into the paint pipe from the first pig landing part side.   The cleaning fluid is supplied into the paint pipe from the second pig landing part side in a state in which the movement of the pig to the first pig landing part side is restricted in the cleaning step. The paint recovery method according to 10 or 11.   In the painting step, as the paint is supplied, the pig moves from the second pig landing part to the first pig landing part via the paint pipe and communicates with the main passage of the first pig landing part. The paint recovery method according to claim 10, wherein one of at least two sub-passages is blocked. The extrusion fluid used in the recovery step is
A first layer composed of air or a solvent, and a second layer composed of a cleaning liquid for cleaning the inside of the paint pipe,
The paint recovery method according to claim 10, wherein the first layer is interposed between the pig and the second layer in the paint pipe.   The pressure in at least one main passage of the first or second pig landing part is detected, and based on the detection result, it is determined whether or not the pig is located in the first or second pig landing part. The paint recovery method according to claim 10, further comprising a determination step.   In the determining step, it is determined whether or not the pig is located in the first or second pig landing part based on a differential pressure in the main passage of the first and second pig landing parts. The paint recovery method according to claim 15. In the determining step,
When the pressure in the main passage of the first pig landing part is different from the pressure in the main passage of the second pig landing part, it is determined that the pig is located in the paint pipe;
When the pressure in the main passage of the first pig landing part and the pressure in the main passage of the second pig landing part are substantially the same, the pig is in the first or second pig landing part. The paint recovery method according to claim 16, wherein the paint recovery method is determined to be located.

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