JPH034372Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rotary atomization electrostatic coating device that can selectively use multiple colors.

[Conventional technology]

Conventionally, an electrostatic coating device as shown in FIG. 2 has been used. Figure 2 shows an example of a mini-bell electrostatic atomizer, which has a cup-shaped atomizing head 10.
(hereinafter referred to as a bell cup) is connected and fixed to the rotating shaft of the air motor 12, and the high voltage generated by the high voltage generator 14 is passed through the air motor 12 to the bell cup 1.
0, thereby performing electrostatic painting while the bell cup 10 rotates. The air motor 12 is supported by one end of an insulating support 16, and the other end of the insulating support 16 is attached to a movable or fixed frame by a stand 18. The paint is supplied to the bell cup 10 through a trigger valve 24 and a hose 26, which are attached to the air motor 12 by a color change cleaning device 20, a hose 22, and a bracket 23. The color change cleaning device 20 consists of a manifold 28 equipped with a large number of valves a to v.
8 is placed in the ground area. The valves a to t are called color valves, and are connected to a supply source of paint of a different color, and the figure shows circulation hoses 30, 31 and cutoff valves 32, 33 only for color valve e. Beyond the shutoff valves 32 and 33, there are tanks and pumps (not shown). Valves u and v are for flowing cleaning solvent and cleaning air.

In the coating equipment shown in FIG. 2, a problem of metal bridging occurred. That is, when using a metal-based paint, a phenomenon occurred in which high voltage could not be applied to the bell cup 10. This is because when the flow of the metal-based paint in the hose 22 is stagnant, the metal particles in the hose 22 become tangled and the voltage leaks through the hose 22 to the ground of the manifold 28. Once metal bridging occurs, the metal bridging does not disappear even if the paint is made to flow again, making it impossible to paint.

To eliminate metal bridging, a device as shown in FIG. 3 is currently used. In FIG. 3, the color change cleaning device 20 is attached to the air motor 12 in the high voltage range by a bracket 34, and metal bridges are prevented by setting both ends of the hose 22 to the same potential.

[Problem that the invention attempts to solve]

In the device shown in Fig. 3, due to restrictions on the mounting structure, only about eight color bulbs can be attached at most, as shown by a to h.
Only about eight colors were available, and the coloring ability was low. Furthermore, a large number of valves are installed near the paint machine,
In addition, since hoses are drawn out from each valve, dust and debris are often generated, especially in top machines where the object to be coated passes through the bottom of the sprayer.
Additionally, colored spots were observed due to paint mist adhering to the valves.

[Means for solving problems]

The rotary atomizing electrostatic coating device according to the present invention includes an air motor attached to an insulating support,
An atomizing head connected to the rotating shaft of this air motor,
This color change cleaning device is equipped with a high voltage generator for applying high voltage to the atomization head, and a color change cleaning device connected to the atomization head by a hose to supply paint to the atomization head. is supported by an insulating material and connected by a conductor so as to have the same potential as the atomizing head.

〔Example〕

In FIG. 1, a bell cup (atomizing head) 10 is connected and fixed to the rotating shaft of an air motor 12, and a high voltage (for example, -90 kv) generated by a high voltage generator 14 is generated.
is applied to the bell cup 10 via the air motor 12, thereby electrostatically coating the object to be coated in the ground area while the bell cup 10 rotates. The air motor 12 is supported by one end of an insulating support 16, and the other end of the insulating support 16 is movable by a stand 18.
Alternatively, it can be mounted on a fixed frame. For example, when painting the body of an automobile, a portal-shaped movable frame is used. Such frames are usually earthed.

The paint is supplied to the bell cup 10 through a color change cleaning device 20, a paint hose 22, and a trigger valve 2 attached to the air motor 12 via a bracket 23.
4. Performed via the paint hose 26. The color change cleaning device 20 consists of a manifold 28 equipped with a large number of valves a to v. Valves a to t are called color valves, and are connected to a supply source of paint of a different color, and the figure shows circulation hoses 30, 31 and cutoff valves 32, 33 only for color valve e. , all color valves are connected similarly.
Beyond the shutoff valves 32 and 33, there are tanks and pumps (not shown). Valves u and v are for flowing cleaning solvent and cleaning air.

In the present invention, the color change cleaning device 20 is supported via insulating materials 36 and 38. Insulating material 36,3
It is preferable that the support 8 is made of a material such as MC nylon or Delrin having a resistance of 1×10 ⁸ Ω or more like the insulating support 16, and has a length that is a surface insulation distance of 30 cm or more. Color change cleaning device 20
is thus supported through the insulating materials 36 and 38 and can be attached to the vertical wall of the portal-shaped movable frame in the ground area described above. Therefore, the color change cleaning device 20 does not need to be directly attached to the air motor 12, and since the above-mentioned frame has sufficient free space, the number of color valves installed can be increased to 20 or more. . Further, the falling of dust and paint dust onto the object to be coated, which was a problem with the conventional technique shown in FIG. 3, is eliminated. The color change cleaning device 20 supported in this manner further includes a conductor (conductor).
electrically connected to the air motor 12 by 40;
That is, the bell cup 10 is brought to the same potential as the high voltage.

Next, the effect will be explained.

During painting, for example, the color valve k is opened,
The high voltage generator 14 is turned on and a high voltage of -90KU is applied. The air motor continues to rotate. Therefore, K color paint is supplied to the bell cup 10 from a paint supply source (not shown) through the color valve k, the paint hose 22, the trigger valve 24, and the paint hose 26, and is subjected to centrifugal force along the inner surface of the bell cup 10. It flies out as it becomes atomized and adheres to the object to be coated in the ground area due to electrostatic force.

When the color is changed to J after finishing the K color painting, the color valve k is first closed and the high voltage generator 14 is turned off. Air motor 12 continues to rotate. Next, the cleaning air valve v is opened and the K color paint inside the hoses 22 and 26 is pushed out.
Furthermore, the cleaning solvent valve u is opened and the hose 22,
26, and the bell cup 10 are washed. After repeating these cleanings several times, color valve j is opened and the hoses 22 and 26 are filled with J color paint. This filling is performed by a short blow operation. At this point, preparations for painting J color are completed, and a painting command is given.
At this time, the flow of paint in the hose 22 was stagnant, and if the high voltage generator was turned on at this point, there was a possibility that the metal bridge described in the prior art would occur. According to the present invention, the color change cleaning device 2
Since the air motor 12 and the color change cleaning device 20 are at the same potential, the air motor 12 and the color change cleaning device 20 are at the same potential, so the hose 22 between them In this case, metal bridges do not occur.

[Effects of the invention] As explained above, according to the invention, a large number of colors (for example, 20
It is now possible to paint with different colors (colors or more).

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a diagram illustrating a conventional technique, and FIG. 3 is a diagram illustrating another conventional technique. 10...Atomization head, 12...Air motor, 14...
...High voltage generator, 16...Insulate support, 20...Color change cleaning device, 22...Hose, 3
6, 38... Insulating material, 40... Conductor.

Claims (1)

[Scope of utility model registration request] an air motor attached to an insulating support; an atomizing head connected to a rotating shaft of the air motor; a high voltage generator for applying a high voltage to the atomizing head; and an atomizing head for applying paint to the atomizing head. A color changing cleaning device is provided which is connected to the atomizing head by a hose for supplying water, and the color changing cleaning device is supported by an insulating material and connected to the atomizing head by a conductor so as to have the same potential. A rotary atomizing electrostatic coating device characterized by: