JP3069279B2 - Electrostatic coating equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic coating apparatus for supplying a conductive paint to a coating gun to which a high voltage is applied through a paint supply path to perform electrostatic coating.

[0002]

2. Description of the Related Art In general, an electrostatic coating apparatus for a conductive paint is configured such that a conductive paint is supplied from a paint supply source via a paint supply path to a coating gun to which a high voltage is applied.
The work is configured to perform electrostatic coating.
For this reason, it is necessary to electrically insulate the coating gun from the paint supply source during electrostatic coating by the coating gun.

In view of the above, there is known an electrostatic coating apparatus for a conductive paint in which a paint supply path connecting a paint supply source and a coating gun can be separated from the paint supply path with an insulation distance on the way (for example, a real paint coating apparatus). See JP-A-4-87755). This will be schematically described with reference to FIG. 7. In the paint supply pipe 2 connected to the paint supply source 1, a male coupler 4 that can move forward and backward through a cylinder 3 is provided, and a female coupler 5 is provided.
Is connected to a pump 7.
Further, the pump 7 is connected to a coating machine 9 through a paint discharge port 8.
The cleaning cover 10 is arranged so as to surround the female coupler 5, and the cleaning liquid supply pipe 11 and the discharge pipe 12 are connected to the cleaning cover 10.

Therefore, a male coupler 4 and a female coupler 5
Is connected, the paint supply pipe 1
Is supplied with a paint of a desired color, the paint is charged from a paint inlet 6 into a pump 7 and further sent to a coating machine 9 through a paint outlet 8. Next, the paint is sprayed from the coating machine 9 under the action of the pump 7 with the male coupler 4 separated from the female coupler 5 and maintaining the insulation distance.

[0005]

In the above prior art,
A cleaning liquid supply pipe 11 and a discharge pipe 12 are provided on the side of the coating machine 9 to which a high voltage is applied. Therefore, in order to insulate, after cleaning the cleaning cover 10, the operation of drying the cleaning liquid supply pipe 11 and the discharge pipe 12 takes a considerable amount of time, and the efficiency of the cleaning operation is not easily achieved. The problem has been pointed out.

Further, paint tends to adhere to and accumulate on the inner surface of the discharge pipe 12, and the accumulated paint may cause a high electric leakage. Accordingly, it is necessary to provide a means for exclusively cleaning the discharge pipe 12, and there is a problem that the cost rises. An object of the present invention is to solve such a problem, and an object of the present invention is to provide an electrostatic coating apparatus that can efficiently and reliably perform a cleaning operation of a path and can simplify a configuration. And

[0007]

In order to solve the above-mentioned problems, the present invention provides a non-application side supply passage through a first on-off valve.
A first valve body having a first through hole that is freely communicable, and an application side supply
A second passage having a second through-hole that can be freely communicated with the passage through a second on-off valve.
2 valve body, and the first
The first and second valve body portions are joined to each other to form the first
The second communication hole communicates with the second communication hole to form a communication hole. There
Then, from the cleaning liquid supply path provided near the second valve body,
When the cleaning liquid is supplied to the communication hole through the second communication hole, the cleaning liquid is supplied to the vicinity of the first valve body after cleaning the communication hole.
Is discharged to a dump path provided in the vehicle. Thus, non-
Since the dump path is provided on the first valve body side on the application side,
There is no high pressure leak from this dump path,
Through hole cleaning work can be performed efficiently in a short time and with a small amount of cleaning liquid.
Is performed.

Further , according to the present invention, it is possible to freely communicate with the dump path.
Other cleaning liquid supply path is provided such. For this reason , the cleaning liquid is supplied to the communication hole from the other cleaning liquid supply path through the first communication hole , so that the entire high voltage application side supply path from the communication hole to the coating gun is reliably cleaned. can do. Therefore, since the communication hole is washed from both directions,
The paint does not remain in the communication holes, and it is possible to effectively prevent color mixing of the paint.

[0009]

FIG. 1 is a schematic structural explanatory view of an electrostatic coating apparatus 20 according to the present embodiment. The electrostatic coating device 20 includes a grounded color changing valve mechanism 22 for selectively supplying a plurality of different coating paints, and a coating gun 24 for spraying the paint.
An intermediate storage tank 26 interposed between the color changing valve mechanism 22 and the coating gun 24; and supply paths 28a and 28b provided between the intermediate storage tank 26 and the color changing valve mechanism 22.
And an insulated separation valve mechanism 30 that can freely contact and separate.

The color changing valve mechanism 22 includes air (A), water (W)
Cleaning valve 32 for controlling the supply of cleaning liquid (S) and the like
And a plurality of paint valves 3 capable of supplying different paints
4a to 34c. The insulation separation valve mechanism 30
A movable block 36 is connected to the color changing valve mechanism 22 via a supply path 28a on the non-applying side. As shown in FIG.
8 and is movable in the direction of arrow A under the guide action of the rail 42.

As shown in FIG. 3, the rail 42 is fixed in a casing 44 constituting the electrostatic coating apparatus 20 and has a substantially arched cross section. Projecting portions 46a, 46 projecting toward
b is formed. The movable block 36 has a protrusion 46
a locking member 48a for engaging the movable block 36 with the projections 46a, 46b by engaging with the projections 46a, 46b;
48b is fixed. The movable block 36 includes the locking member 4.
8a, 48b, the projections 46a, 46b are supported on the horizontal and vertical surfaces, and between the upper end surface 36a of the movable block 36 and the lower end surface 42a of the rail 42,
A gap H is formed.

As shown in FIG. 4, the movable block 36 is provided with a first valve body 52 formed with a first through hole 50 communicating with the supply passage 28a.
0 and the supply path 28a are opened and closed via a first on-off valve 54. The first opening / closing valve 54 includes a valve body 60 that can move forward and backward through the resilience of a spring 56 and air that is introduced and drawn into an air port 58, and a valve seat 62 on which the valve body 60 can be seated.

The movable block 36 is provided with first and second dump paths 64 and 66 that are branched from the supply path 28a in proximity to the first valve body 52. This first and second
On the way of the dump paths 64, 66, the first and second dump paths 64, 66 are as close as possible to the first on-off valve 54.
And first and second dump valves 68 and 70 for opening and closing the valve. The first and second dump valves 68, 70
The valve bodies 80 and 82 which can move forward and backward through the resilient forces of 2, 74 and the air introduced and drawn out to the air ports 76 and 78, and the valve seats 84 and 86 on which the valve bodies 80 and 82 can seat. Prepare.

The first through hole 50 of the first valve body 52 is provided with a second
A first cleaning path (another cleaning liquid supply path) 88 communicates via the dump path 66, and the movable block 36 has a cleaning liquid flowing from the first cleaning path 88 toward the first through hole 50. The first check valve 90 that allows only the flow of the first check valve 90 is mounted. The first cleaning path 88 communicates with a second cleaning valve 94 via a first switching valve 92 as shown in FIG.

As shown in FIG. 2, a fixed second valve body 96 is disposed in the casing 44 so as to face the first valve body 52. The second valve body 96 has a second through-hole 98 formed therein, and the second through-hole 98 can freely communicate with the supply path 28 b on the application side via the second on-off valve 100. As shown in FIG. 5, the second valve body 96 and the second on-off valve 100 are provided in a fixed block 102,
The second valve body 96 is provided with a first valve body 5 which is a male connecting portion.
2 constitutes a female connecting portion.

[0016] The isolation valve mechanism 30, when the first and second valve body 52,96 are joined, the first and second
The communication hole 104 communicates with the communication hole 104 to form a communication hole 104, and the second dump path 66 branches off from the communication hole 104 in a state where the first on-off valve 54 is closed (see FIG. 4).
As shown in FIG. 5, in the vicinity of the second valve body 96, a second cleaning path (cleaning liquid supply path) 108 communicates via a second check valve 106, and the second cleaning path 108 is switched to the second switching mode. It communicates with the second cleaning valve 94 via the valve 110 (see FIG. 1). In the present embodiment, the insulation separation valve mechanism 30
The first supply port 28a can be freely communicated with the first supply
A first valve body 52 having one through-hole 50 and an application-side supply passage 2
8b through the second opening / closing valve 100 to the second through hole 9
8 and the first valve body 52 and the front
Joining and separating the second valve body 96 from each other
Communicates the first through-hole 50 and the second through-hole 98
And an air cylinder (drive means) 38 which can be shut off and
The first through-hole 50 is provided near the first valve body 52.
A second dump path 66 communicating with the second dump path
66, which opens and closes the second dump path 66
A second dump valve 70 and a second valve body 96 in the vicinity thereof.
And the second through-hole 9 through the second check valve 106.
8 and the first and second through holes 50,
The communication hole 104 formed by communicating with the second communication hole 98 is formed in the second communication hole 9.
The second cleaning path (cleaning liquid supply
Road) 108. Furthermore, the insulation separation valve mechanism 30
Is close to the second dump valve 70 and the first check valve 90
1st washing | cleaning path | path freely communicable with 2nd dump path | route 66 through
(Another cleaning liquid supply path) 88, the first cleaning path
From 88, the cleaning liquid is supplied to the communication hole 104 through the first communication hole 50.
It is configured to supply.

As shown in FIG. 2, the intermediate storage tank 26 includes a cylinder 112, which is held in the casing 44 via insulating columns 114a to 114d formed of four resin tubes. Insulated pillar 11
4a is configured to be long so as to extend to the coating gun 24 side. A piston 116 is disposed in the cylinder 112 so as to be slidable in a reciprocating manner, and a paint filling cylinder chamber 118 is formed by the inner wall of the cylinder 112 and the tip of the piston 116.

The distal end surface 120 of the piston 116 is formed of a convex tapered surface protruding toward the cylinder wall 122 of the cylinder 112. An injection hole 124 is formed in the cylinder wall 122 at the inner peripheral edge thereof and communicates with the supply passage 28b, while a discharge hole 126 is formed at the center thereof and communicates with the coating gun 24. Is provided. A plunger 128 is connected to the piston 116, and a nut member 130 provided in the plunger 128 is connected to a ball screw 1 connected to a rotation shaft 134 of a servomotor 132.
36 is screwed.

The coating gun 24 includes high voltage applying means 140 connected to a low voltage cable 138, and the low voltage cable 138 is connected to a power source (not shown) through the inside of the insulating pillar 114a. A third cleaning valve 144 communicates with a tip side of the coating gun 24 via a third cleaning path 142 (see FIG. 1). The operation of the electrostatic coating device 20 thus configured will be described below.

First, at the time of electrostatic coating, the movable block 36 is guided by the rail 42 and moves in the direction of the arrow A1 under the action of the air cylinder 38 constituting the insulating separation valve mechanism 30 (in FIG. 2, a two-dot chain line). reference). Thus, the first valve body 52 is joined to the second valve body 96, and the first and second through holes 50 and 98 communicate with each other to form the communication hole 104.

When a predetermined color paint is fed from the paint valve 34a of the color changing valve mechanism 22, the paint is supplied to the supply passage 2 by the opening action of the first and second on-off valves 54 and 100.
8a is supplied to the supply path 28b through the communication hole 104. For this reason, the paint is filled into the cylinder chamber 118 from the injection hole 124 and further to the coating gun 24 through the discharge hole 126.

Next, the first and second on-off valves 54, 100
The first and second valve body portions 52, 96 are
The work of cleaning the communication hole 104 formed between the two is performed. That is, as shown in FIG. 1, the second switching valve 110 is opened, and water and air are sequentially supplied from the second cleaning valve 94 to the second valve body 96 via the second cleaning path 108.
The water and air introduced into the second valve body 96 are
After the paint remaining in the communication hole 104 from the second through hole 98 side of No. 6 is washed, it is discharged to the second dump path 66 under the opening action of the second dump valve 70 (see arrow X in FIG. 1).

As described above, in the present embodiment, the work of cleaning the communication hole 104 is performed via the second cleaning valve 94, and the cleaning liquid used for this cleaning is removed from the second dump valve 70 on the non-application side.
From the second dump path 66. Accordingly, high pressure leak does not occur from the second dump path 66, and the operation of cleaning the communication hole 104 can be performed in a shorter time and a smaller amount of the cleaning liquid as compared with the case where the dump path is provided on the second valve body 96 side on the application side. The effect that it is easily carried out is obtained.

That is, when the second dump path 66 is on the application side, an extremely high level of dump path cleaning work is required in order to prevent high pressure leakage due to paint adhered to the inner surface of the second dump path 66. On the other hand, in the present embodiment, since the second dump path 66 is provided on the non-application side, there is no problem even if the paint remains on the inner surface of the second dump path 66. Therefore, the dump path cleaning work is not actually required.

While the communication hole 104 is being cleaned, the tip of the coating gun 24 is connected to the third cleaning valve 14.
The cleaning is performed by the water and the air supplied through the third cleaning path 142 under the action of 4. After the cleaning operation of the communication hole 104 is completed, the air cylinder 38 is driven to separate the first valve body 52 from the second valve body 96 with an insulation distance (see the solid line and FIG. 6 in FIG. 2). ). Then, in order to perform the color changing cleaning operation, the area from the supply path 28 a to the first opening / closing valve 54 is cleaned via the first cleaning valve 32, and the cleaning liquid used for this cleaning is supplied to the first dump valve 68. It is discharged to the first dump path 64 under the opening action (see arrow Y in FIG. 6). As a result, the color changing valve mechanism 22 becomes capable of supplying paints of different colors.
2 supplies new paint from the paint valve 34b to the supply path 28a, and waits.

On the other hand, in the intermediate storage tank 26, the ball screw 1
36 is rotated. For this reason, the plunger 128 moves in the direction of the arrow A1 in FIG. 2 integrally with the piston 116 via the nut member 130 screwed to the ball screw 136, and the high-voltage applying means 140 is driven. Thereby, the paint to which the high voltage is applied is applied from the painting gun 24 toward the work (not shown).

When the coating with the paint filled in the cylinder chamber 118 of the intermediate storage tank 26 is completed and a paint of a color different from this paint is used, first, a high voltage is applied to the paint. After being released, the first valve body 52 is joined to the second valve body 96 under the action of the air cylinder 38. Next, a cleaning operation on the intermediate storage tank 26 side (high pressure application side) is performed via the second cleaning valve 94. That is, after the piston 116 is disposed at a predetermined position under the action of the servomotor 132, the first on-off valve 100 is opened and the first
Water and air are sequentially introduced from the second cleaning valve 94 through the switching valve 92 to the supply path 28b through the first cleaning path 88. This water or air is supplied from the injection hole 124 to the cylinder chamber 1.
After the inside of the cylinder chamber 118 is cleaned, it is introduced into the coating gun 24 through the discharge hole 126 and discharged to the outside (see a broken line Z in FIG. 1).

As described above, in the present embodiment, the communication holes 10
After cleaning the sample No. 4 from the application side to the non-application side, a cleaning liquid is supplied to the communication hole 104 from the non-application side to the application side. This makes it possible to prevent the paint from remaining in the insulating separation valve mechanism 30 with an extremely simple configuration, and to reliably avoid the problem that the remaining paint is dried and solidified to cause a high-pressure leak and color mixing of the paint. It becomes possible.

When performing the color change cleaning in the electrostatic coating apparatus 20, the coating gun 2 is applied through the high voltage applying means 140.
While the high voltage is applied to 4 and the electrostatic coating is performed, the cleaning and drying processes from the supply path 28a to the first on-off valve 54 are performed, and the new paint is filled in the supply path 28a. . Therefore, after the completion of the electrostatic coating, the second cleaning valve 9
It is only necessary to carry out the cleaning and drying operations of the path after the supply path 28b, which is the high-pressure application side, via 4, the effect that the entire color changing cleaning operation can be performed extremely quickly and efficiently.

Further, in the present embodiment, the movable block 3
6 is supported on the rail 42 via locking members 48a and 48b.
A gap H is formed between the rail a and the lower end surface 42a of the rail 42. Therefore, when the movable block 36 moves forward and backward in the direction of the arrow A, the lower end surface 42a and the upper end surface 36a do not slide to generate dust, and, for example, the second valve body portion 96 moves to the supply passage 28b. It is possible to avoid the problem that the cutting powder enters.

Further, in this embodiment, as shown in FIG. 2, a low-voltage cable 138 is provided in a long insulating pillar 114a extending to the coating gun 24. This makes it possible to prevent the low-voltage cable 138 from becoming a ground when a high voltage is applied to the coating gun 24 by the high-voltage applying means 140. In addition, as shown in FIG. 4, the first and second dump paths 64, 66
The first and second dump valves 68 and 70 are provided as close as possible to the first on-off valve 54 while branching off from the supply passage 28a in the vicinity of the valve seat 62 of the on-off valve 54.
Therefore, it is possible to effectively reduce the remaining amount of paint washing,
Moreover, there is an advantage that wasteful paint can be greatly reduced.

[0032]

As described above, in the electrostatic coating apparatus according to the present invention, the dump path is provided in the vicinity of the first valve body on the non-application side, and provided in the second valve body on the application side. The cleaning liquid supplied to the communication hole from the cleaning liquid supply path is discharged to this dump path. For this reason, the high pressure leak does not occur from the dump path, and the work of cleaning the communication path is efficiently performed in a short time and with a small amount of the cleaning liquid.

[Brief description of the drawings]

FIG. 1 is a schematic configuration explanatory view of an electrostatic coating apparatus according to the present invention.

FIG. 2 is an explanatory longitudinal sectional view of a main part of the electrostatic coating apparatus.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is an explanatory sectional view of a movable block constituting the electrostatic coating apparatus.

FIG. 5 is an explanatory sectional view of a fixed block constituting the electrostatic coating apparatus.

FIG. 6 is an explanatory view of a state where first and second valve bodies constituting the electrostatic coating device are separated.

FIG. 7 is a schematic diagram illustrating the configuration of an electrostatic coating apparatus according to a conventional technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 20 ... Electrostatic coating device 22 ... Color change valve mechanism 24 ... Coating gun 26 ... Intermediate storage tank 28a, 28b ... Supply path 30 ... Insulation separation valve mechanism 32,94 ... Cleaning valve 34a-34
c: paint valve 36: movable block 38: air cylinder 42: rail 52, 96 ...
Valve parts 54, 100 ... On-off valves 64, 66 ...
Dump path 68, 70 ... Dump valve 88, 108
... Washing path 90,106 ... Check valve 92,110
... Switching valve 102 ... Fixed block 104 ... Communication hole 112 ... Cylinder 118 ... Cylinder chamber

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B05B 5/16 B05B 5/08

Claims (2)

(57) [Claims] An electrostatic coating apparatus for supplying a conductive paint to a coating gun to which a high voltage is applied through a paint supply path to perform electrostatic coating, wherein the high voltage is applied to the paint supply path. An insulating separation valve mechanism which is electrically insulated and separable from the application side supply path to be applied and the other non-application side supply path, wherein the insulation separation valve mechanism is configured to first open and close the non-application side supply path. A first valve body having a first through-hole communicable through a valve, and a second valve communicable through the second on-off valve to the application-side supply path .
A second valve body having a through-hole; and joining and separating the first valve body and the second valve body from each other, thereby forming the first through-hole and the second through-hole.
And communicating and blocking freely drive means, communicating with the first through hole before SL provided in the vicinity of the first valve body portion
And dump path for a dump valve for opening and closing the dump path is disposed on the way of the dump path, provided in the vicinity of the second valve body portion, the second through the valve
The first and second through holes communicate with the through hole.
Electrostatic coating apparatus for a communication hole which is formed through the cleaning liquid supply path for cleaning from the second through hole side, characterized in Rukoto equipped with. 2. An electrostatic coating apparatus according to claim 1, wherein said electrostatic coating apparatus is adjacent to said dump valve and communicates with said dump path via said valve.
Comprising a freely other cleaning liquid supply path, by supplying a cleaning liquid to the communication hole through the first hole from the other of the cleaning liquid supply passage, electrostatic, characterized by washing the applied side supply passage Electrocoating equipment.