JPH0144111B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a rotary atomizing electrostatic coating device, and more particularly to a rotary atomizing electrostatic coating device that is used by being attached to the wrist of a painting robot.

Conventional technology Conventionally, a general rotary atomizing electrostatic coating device (for example, a rotary atomizing electrostatic coating device used in a fixed stand or a reciprocating machine (reciprocator)
No.) is 60kV to 120kV to obtain high coating efficiency.
Because it is used at a high voltage (average operating voltage of 90kV), the total length is over 500mm and the weight including the color change device.
It was common for the weight to be over 10 kg. On the other hand, commercially available articulated painting robots have limited weight capacity, so the weight of the painting equipment must be less than 5 kg, and the overall length must be less than 5 kg.
It is necessary to make the total length 300 mm or less, but when the total length is 300 mm or less, it is difficult to secure an insulation distance that can withstand high voltage. When using the average working voltage as 90kV, the minimum insulation distance is 150mm or more,
Desirably, the distance is 200 mm or more. Especially in the case of metallic painting, the paint adheres to the outer periphery of the insulating part of the coating equipment, and the aluminum particles present inside this adhered paint cause a bridging phenomenon, so the insulation distance is substantially reduced. This makes it even more difficult to ensure insulation.

Problems to be Solved by the Invention The purpose of the present invention is to provide a small and lightweight rotary atomizing electrostatic coating device that can be used by being attached to an articulated or polar coordinate type coating robot, which can be used at a high voltage of 60 kV or higher. The object of the present invention is to maintain sufficient insulating properties as possible, and to maintain insulating properties by keeping the outer insulating part sufficiently clean even when applied to metallic coatings.

Means for Solving the Problems In order to solve these problems, the present invention provides a rotary atomizing electrostatic coating device to be attached to the wrist of a painting robot, which includes a device body made of resin and , a bell head provided at the front end of the main body and to which a high voltage is applied; a drive device provided inside the main body for rotating the bell head; a paint supply means for supplying paint to the rotating bell head; and an air injection means for deflecting paint particles scattered by centrifugal force toward the object to be coated in front, the air injection means including the air injection port installed on the outer peripheral side of the bell head, and It includes a rear air injection port located on the outer circumferential side of the air injection port and 50 mm or more rearward from the front end of the main body, and the distance in the front-rear direction from the front end of the main body to the tip of the robot wrist is 150 mm or more. A rotary atomization electrostatic coating device is provided.

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the figure, a flexible wrist 3 is formed at the front of a horizontal arm 2 of an articulated painting robot 1, and a small rotary atomizer for robots is attached to the tip 4 of the wrist via a resin attachment part 5. An electrostatic coating device main body 6 is attached.

The main part of the device main body 6 consists of a resin insulating part 10 that surrounds and holds the air motor 7 therein. A metal rotary bell head 9 to which a high voltage is applied is provided at the front end (left end in the figure) of the main body 6, and this bell head 9 is screwed onto the shaft 8 of an air motor 7. At the front end of the main body 6 and around the bell head 9, an air injection port 12 and an annular air supply passage 1 are provided.
An annular resin attachment 14 having a diameter of 3 is attached. The air injection ports 12 are arranged along a circle symmetrically with respect to the rotation axis of the bell head 9, and are designed to inject air in the direction of arrow A in the figure (that is, parallel to the rotation axis). The diameter of the air injection ports 12 is usually 0.3 mm to 2 mm, and the number of air injection ports 12 is 20 to 100.

The device body 6 is attached to the robot wrist 3, that is, the robot side attachment portion 5, via a resin body attachment plate 11 fixed thereto. At the front of the main body mounting plate 11 and on the outer periphery of the main body 6, air injection ports 15 and 16 are provided, and air supply paths 1 for these air injection ports 15 and 16 are provided.
An annular resin attachment 18 having a diameter of 7 is attached. The air injection ports 15 and 16 are arranged symmetrically with respect to the rotation axis of the bell head 9 outside and behind the air injection port 12, respectively, along circular and conical shapes. The diameter of the air injection ports 15 is usually 0.3 mm to 2 mm, and the number thereof is 20 to 100, and the air injection direction B is parallel to the rotation axis of the bell head 9. Further, the air injection ports 16 have the same diameter, usually 0.3 mm to 2 mm, and the number of air injection ports 16 is 20 to 100, but the air injection direction C is a direction in which the air injection ports 16 widen in a conical shape forward with respect to the rotation axis of the bell head 9.

A high voltage (usually 60 to 120 kV) is applied to the bell head 9 from the rear of the main body 6 via a high voltage cable 19. The air motor 7 is rotated by compressed driving air supplied through a hose 20 led from the rear of the main body 6 and an air supply port 21 inside the main body 6, and the used air is discharged from an air exhaust port 22 and a muffler (silencer). ) 23 and is exhausted to the rear of the main body 6. The paint is supplied through a paint hose 24 at the rear of the main body 6,
The paint is supplied through a paint tube 26 inside the main body 6, and is sprayed from the paint tube 26 toward the bell head 9. Compressed air is supplied to the air supply paths 13 and 17 via air hoses 27 and 28 at the rear of the main body 6 and air supply ports 29 and 30 inside the main body 6, respectively.

This device has an insulation distance a from the bell head 9 (front end of the main body 6) which is a high voltage applying part to the tip 4 of the robot wrist 3 which is the ground part to which the main body 6 is attached.
should be 150mm or more (preferably 200mm or more),
The total length is 300 mm or less (weight is about 2 to 3 kg), and the air injection port 1 is connected from the front end of the main body 6.
The distance b to the annular resin attachment 18 of 5 and 16 is 50 mm or more, preferably 100 mm or more.
Also, paint hose 23, air hoses 19, 27, 2
8, the high voltage cable 19 and the muffler 23 are all attached to the rear part of the device body 6.

The operation of this device will be explained below. Paint is supplied from a paint tube 26 to a rotary bell head 9 driven by an air motor 7 and atomized in a centrifugal direction. These atomized paint particles are deflected in the direction of the article to be coated (not shown) in front by an air stream A, usually called pattern air, which is injected from the air injection port 12, and the high voltage applied to the bell head 9 is applied to the object to be coated (not shown). Electrostatic painting is achieved by superimposing the effects of voltage. In this case, there are a small number of paint particles that penetrate the air flow A and are scattered in the centrifugal direction. B and C transport the paint toward the front object to be painted, thereby preventing paint from adhering to the outer circumference of the device body 6. This effect of preventing paint adhesion is due to the fact that the paint hose 24, air hoses 20, 27, 28, high-voltage cable 19, and muffler 23 are concentrated at the rear of the main body 6, and there are no obstacles to the air flows B and C. It's becoming more advantageous.

Effects of the Invention Since the device of the present invention has an insulating structure made of resin around the outer periphery to ensure an insulation distance, the device has a short overall length and is light in weight, so it can be used even in robots with a small payload. In addition, the air flow that is superimposed on the normal pattern air from near the outer circumference of the bell head and injected from the rear outer circumference prevents paint from adhering to the outer circumference of the device body, ensuring sufficient insulation and safety even in the case of metallic painting. . Furthermore,
The effect of the air flow from the rear allows the coating pattern to be converged to a smaller size and the coating efficiency to be further increased, making it possible to maintain high coating efficiency even in the low applied voltage range of 30 to 60 kV. It is also possible to reduce the risks caused by

[Brief explanation of drawings]

The figure is a side sectional view showing an embodiment of the rotary atomization electrostatic coating apparatus of the present invention. 1...Painting robot, 3...Flexible wrist, 4...Front end of wrist, 5...Mounting section, 6...Device body, 7...Air motor, 9...Bell head, 1
0... Body resin part, 11... Mounting plate, 12... Said air injection port, 15, 16... Rear air injection port,
26...Paint tube.

Claims (1)

[Claims] 1 A rotary atomizing electrostatic coating device to be attached to the wrist 3 of a painting robot 1, which includes a device body 6 made of resin, a bell head 9 provided at the front end of the body and to which a high voltage is applied, and the bell head. A drive device 7 provided inside the main body for rotation, and a paint supply means 2 for supplying paint to the rotating bell head.
4, 25, 26, and air injection means 12, 15, 16 for directing paint particles scattered by the centrifugal force of the bell head toward the object to be coated in front of the bell head. It includes a front air injection port 12 installed on the outer periphery side, and also includes rear air injection ports 15 and 16 located on the outer periphery side of the front air injection port and at least 50 mm rearward b from the front end of the main body 6. A rotary atomizing electrostatic coating device characterized in that a distance a in the front-rear direction from the front end of the main body 6 to the tip 4 of the robot wrist 3 is 150 mm or more.