JPH07236839A - Multicolor electrostatic coating machine - Google Patents

Abstract

PURPOSE:To miniaturize a multicolor electrostatic coating machine wherein coating compound supply pipes supplying respective color coating compounds to a rotary atomizing head are inserted and arranged in the tubular rotary shaft of an air motor and to supply coating compound to the rotary atomizing head only directly connecting many hoses to the rear end of the electrostatic coating machine without leaking high voltage to an earth element. CONSTITUTION:The rear end of a machine body 4 consisting of a rotary atomizing head 2 and the air motor 3 rotationally driving the head 2 is received in a bucket- shaped insulating housing 12 and the insulating housing 12 is constituted so that the recessed part 13 receiving the machine body 4 is airtightly formed and at least the outer peripheral surface of the receiving recessed part 13 is formed from an insulating material over required insulating length so that the outside rear end part of the recessed part 13 can be held to an insulated state with respect to the inside thereof. Therefore, a plurality of coating compound passages 15 are formed to the side wall 14 of the insulating housing 12 along the longitudinal direction thereof so as to pierce the same and the opening parts 15a communicating with coating hoses are formed to the rear end of the coating compound passages 15 and the opening parts 15b communicating with the rear ends of coating compound supply pipes Np are formed to the front ends thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multicolor electrostatic coating machine for performing electrostatic coating by selectively selecting a paint having a color corresponding to the coating color of a substrate conveyed by a conveyor.

[0002]

2. Description of the Related Art For example, as shown in FIG. 5, an electrostatic coating machine for coating an automobile body which is continuously conveyed by a conveyor is rotated by a high voltage generator 51 applying a high voltage of, for example, -120 kV. A valve device 55 having a valve that individually supplies each color paint is attached to the back side of a machine body 54 including an atomizing head 52 and an air motor 53 that rotates the atomizing head 52, and is housed in an insulating case 56.

A large number of paint hoses for supplying each color paint, a cleaning solvent supply hose, a cleaning air supply hose, an air hose for controlling the rotation of the air motor 53, an air hose for operating a valve for controlling the supply of each color paint, and the like. A hose 57 penetrates the insulating case 56 and is connected to the valve device 55 and the machine body 54 from the back side thereof.

[0004]

However, since the electrostatic coating machine is used with its rear end attached to a grounding body such as a robot arm, a high voltage applied to the rotary atomizing head 52 is provided in the insulating case 56. In addition, at least the length x of the machine body 54 and the valve device 55 + the insulation length y is required so that the hose insertion hole does not leak to the ground body, and there is a problem that the total length becomes long and the electrostatic coating machine becomes large. It was In particular, since the heavy body 54 is disposed on the tip side of the electrostatic coating machine, when the electrostatic coating machine is tilted to change its posture or is supported horizontally or in a state close to this, There is a problem that an excessive load is applied to the supporting robot arm or the like.

As shown in FIG. 6, the hose 57 is reversed from the rear side of the machine body 54 to the front side thereof, and the insulating case 56 is removed.
The length of the electrostatic coating machine can be shortened by reversing it to the back side at the tip side and circumventing the insulating case 56, but this time, many hoses 57 surround the electrostatic coating machine. Is projected to. Moreover, each hose 57 is quantitative,
Since pressure resistance is required, the rigidity is high and it cannot be bent with a small radius, which causes a problem that it becomes an obstacle when moving the electrostatic coating machine.

In order to prevent this, an insulative hose cover 58 must be attached to the outer side of the hose cover 58, which causes a problem that the electrostatic coating machine becomes large in diameter and large in size. Therefore, it is a technical object of the present invention to make the electrostatic coating machine compact, prevent high voltage from leaking to the grounding body, and connect a large number of hoses by bypassing them without piping. I am trying.

[0007]

In order to solve this problem, the present invention relates to the rotary atomization of each color paint in a tubular rotary shaft of an air motor which rotationally drives a rotary atomizing head to which a high voltage is applied. In a multicolor electrostatic coating machine in which a paint supply pipe for supplying to the head is inserted and arranged, a rear end side of a machine body composed of the rotary atomizing head and an air motor for rotationally driving the head is housed in a bucket-shaped insulating housing, The insulating housing is formed with an airtight recess for accommodating the machine body, and at least the outer peripheral surface of the insulating recess has a required insulation length so that the outer rear end of the accommodating recess can be kept insulated from the inner side. An opening formed in the side wall of the insulating housing so as to penetrate a plurality of paint passages along the longitudinal direction thereof and communicated with the paint hose at the rear end side of the paint passage. Shape While being, at its front side, characterized in that the opening for communicating the rear end of the paint supply tube is formed.

[0008]

According to the present invention, a machine body to which a high voltage is applied is housed in a bucket-shaped insulating housing, and the housing body is formed with an airtight recess for housing the machine body and an outer peripheral surface. Since it is made of an insulating material for at least the required insulation length, the outer rear end portion of the insulating housing in contact with the grounding body is kept in an insulated state with respect to the machine body in the accommodation recess, and the high voltage applied to the machine body is high. There is no leak.

In addition, a plurality of paint passages are formed through the side wall of the insulating housing along the longitudinal direction thereof, and an opening communicating with the paint hose is formed at the rear end side thereof. Since an opening is formed on the front end side that communicates with the paint supply pipe, the paint hose can be connected to the opening on the rear end side of the paint flow path without bypassing the paint hose. Since the multicolor electrostatic coating machine can be formed in a small size, the paint hose does not get in the way even when the posture of the electrostatic coating machine is changed, and the hose cover is unnecessary.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on the embodiments shown in the drawings. 1 is a sectional view showing an example of a multicolor electrostatic coating machine according to the present invention, FIG. 2 is a rear view showing another embodiment,
FIG. 3 is a sectional view showing another multicolor electrostatic coating machine according to the present invention,
FIG. 4 is a rear view thereof.

In the figure, reference numeral 1 designates a machine body 4 comprising a rotary atomizing head 2 to which a high voltage is applied and an air motor 3 for rotationally driving the rotary atomizing head 2.
The multi-color electrostatic coating machine in which each color paint supplied from the back side of the is supplied through the inside of the tubular rotary shaft 5 of the air motor 3 and into the rotary atomizing head 2 attached to the tip of the tubular rotary shaft 5. The cleaning nozzle Nc for supplying the cleaning solvent and the cleaning air and the thin tubular nozzles (coating supply pipes) Np, Np for supplying the respective color paints are arranged in an annular shape with the cleaning nozzle Nc as a center, and the annular shape is used. A needle valve 7 that is inserted into the rotary shaft 5 in a non-contact state and that opens and closes a tip opening portion with a needle 6 is formed in each thin tubular nozzle Np.

On the rear side of the machine body 4, a valve unit Uv having a plurality of valve drive units 8 for opening and closing the needle valve 7 of each thin tubular nozzle Np is attached. The valve unit Uv is formed to have a larger diameter than the machine body 4, and a paint flow path 10 communicating with the nozzle Np and a flow path connected to the nozzle Nc are formed inside the valve unit Uv. Protruding flange 11
An inlet 10a of the paint flow path 10 and an inlet of another flow path are formed on the front side of the vehicle body toward the front side of the machine body.
The valve drive unit 8 includes the needle 6 of the needle valve 7.
Leaf spring piece S for urging the valve spring in the valve closing direction, and the leaf spring pieces S
C that pushes up the valve in the valve opening direction against its urging force
Consists of.

Reference numeral 12 denotes a bucket-shaped insulating housing for accommodating the machine body 4 from its rear end side, in which an accommodating recess 13 for accommodating the machine body 4 is formed airtight, and an outer rear end portion 13a of the accommodating recess 13 is formed. The entire required insulation length (eg 20
cm) made of an insulating material. In addition, in the present invention, not only the case where the entire insulating housing 12 is formed of an insulating material, but as shown in FIG. 2, for example, as shown in FIG. The outer peripheral surface 12b and the bottom surface 12c may be integrally formed of an insulating material, and the portion of the outer peripheral surface 12b may be selected to have a required insulation length.

The side wall 14 of the insulating housing 12 is formed with a plurality of paint flow passages 15 along its longitudinal direction and other flow passages for supplying rotation control air for the air motor 3 and the like. There is. Then, an opening 15a communicating with the paint hose is formed on the rear end side of the paint flow path 15,
On the front end side, a paint passage 1 communicating with the paint inlet 10a
An opening 15b for connecting 6 is formed. The paint channel 15 is formed by inserting a Teflon tube into a through hole formed in the side wall 14.

Uc is a connection unit having a large number of paint flow paths 16 for connecting the paint flow path 15 formed in the insulating housing 12 and the paint flow path 10 formed in the valve unit Uv. With the connection unit Uc attached to the insulating housing 12 and the valve unit Uv, the openings 16a and 16b of the paint passage 16 are respectively the paint inlet 10a of the valve unit Uv and the paint passage 15 of the insulating housing 12. Are formed at positions respectively connected to the openings 15b.

A small high voltage generator 17 is embedded in the bottom 12a of the insulating housing 12 so as to be integrally formed, and has a spring-like power feeding contactor 17a projecting in the accommodating recess 13 and provided with a cylinder. Is in contact with C,
A high voltage is applied to the rotary atomizing head 2 via the valve unit Uv formed of a conductive material and the body 4. Also, 18
Is a cover for covering the front side of the machine body 4, and the cover 1
A space between 8 and the body 4 is formed as a positive pressure chamber that supplies high-pressure air to a shaping air injection slit formed around the rotary atomizing head 2.

The above is an example of the configuration of the present invention, and its operation will be described below. First, when assembling the electrostatic coating machine 1, the valve unit Uv is attached to the back side of the machine body 4, and the machine body 4 is attached to the valve unit Uv in that state.
The connection unit Uc is attached from the front side, and finally the insulating housing 12 is attached to the connection unit Uc from the rear end side of the machine body 4.

As a result, the thin tubular nozzle Np for supplying paint to the rotary atomizing head 2 is insulated via the paint passage 10 formed in the valve unit Uc and the paint passage 16 formed in the connection unit Uc. Since it is connected to the paint flow passage 15 formed on the side wall 14 of the housing 12, the paint hose supplying each color paint is piped without detouring, and simply connected to the rear end opening 15a of the paint flow passage 15. Paint can be supplied to the rotary atomizing head 2. Therefore, the paint hose is connected to the rear end side of the electrostatic coating machine 1 so that the paint hose does not get in the way even when the posture of the electrostatic coating machine 1 is changed, and the electrostatic coating machine 1 is enlarged in the radial direction. It can be formed compactly without performing.

Further, the machine body 4 to which a high voltage is applied is accommodated in the accommodating recess 14 of the insulating housing 12, and the accommodating recess 13 is airtight and has no hole for penetrating a paint hose or the like. Since the outside of the rear end of the insulating housing 12 is kept insulated from the machine body 4 even if the rear end of the insulating housing 12 is not separated from the rear end of the insulating housing 12 by a predetermined insulation length, the total length of the electrostatic coating machine 1 is shortened. Moreover, the high voltage does not leak to the grounding body such as the robot arm that supports the rear end of the insulating housing 12.

Next, the operation method of the electrostatic coating machine according to this embodiment will be described. First, the driving air is supplied to the air motor 3 to rotate the rotary atomizing head 2 at a high speed of about 20,000 to 50,000 rpm, and at the same time, it is small and high. -80 to 120k from the voltage generator 17 to the rotary atomizing head 2 via the feeding contactor 17a
A high voltage of V is applied. Then, for example, when the needle valve 7 of the thin tubular nozzle Np to which the white paint is supplied is opened,
The white paint is supplied to the rotary atomizing head 2 through a paint hose, where it is electrostatically atomized and sprayed, and applied to an object to be coated.

At this time, since the rotary atomizing head 2 is attached to the tubular rotary shaft 5 of the air motor 3, the rotary atomizing head 2 is
A high voltage is applied to the entire machine body 4 including the air motor 3 and the air motor 3. However, since the machine body 4 is supported in an insulated state with respect to the ground body supporting the rear end portion of the insulating housing 12, the high voltage is applied to the ground body. It never leaks. Even if the posture of the electrostatic coating machine 1 is changed during coating, the electrostatic coating machine 1
The electrostatic coating machine 1 because it is compactly formed.
An excessive load is not applied to the robot arm or the like supporting the robot.

FIG. 2 is a sectional view showing another embodiment of the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals and detailed description thereof will be omitted. In this example, the insulating housing 12 is covered with a tubular piping unit Up which is entirely made of an insulating material, and the paint flow passage 15 is formed on the peripheral wall portion 20 along the longitudinal direction of the piping unit Up. There is. The piping unit Up is not limited to the case where the entire pipe unit Up is formed of an insulating material, and if the peripheral wall portion 20 is formed of an insulating material for a required insulation length from the rear end portion toward the front end side, the front end side is conductive. It may be formed of a material.

The electrostatic coating machine 1 of this embodiment is configured to supply the paint into the rotary atomizing head 2 through the tip opening of the paint supply pipe Np inserted into the tubular rotary shaft 5 of the air motor 3. The valve unit Uv attached to the rear surface of the machine body 4 has one end connected to the rear end side of the paint supply pipe Np and an annular flow passage 21 to which the cleaning solvent and the cleaning air are supplied from the other end. There is. A plurality of paint valves V for supplying each color paint are arranged along the annular flow path 21, and a cylinder 23 for opening and closing a needle valve 22 formed at the tip of the paint supply pipe Np is provided in the center thereof.
Is provided. Further, 24 is a high voltage generator, which is mounted along the side wall 14 of the insulating housing 12.

Then, the machine body 4, the valve unit Uv, and the connection unit Uc are assembled, and the piping unit U is attached thereto.
When the inside of the insulating housing 12 enclosing the p is mounted, the thin tubular nozzle Np for supplying the paint to the rotary atomizing head 2 is communicated with the paint passages 10, 16 and 15, so that a paint hose for supplying paint of each color is provided. Paint channel 15 without circumvention
The paint can be supplied to the rotary atomizing head 2 simply by connecting to the rear end opening 15a. Therefore, the paint hose is connected to the rear end side of the electrostatic coating machine 1 so that the paint hose does not get in the way even when the posture of the electrostatic coating machine 1 is changed, and the electrostatic coating machine 1 is enlarged in the radial direction. It can be formed compactly without performing.

Also in this example, the insulating housing 12 is
The accommodating recess 13 for accommodating the machine body 4 is formed airtight, and the entire insulation length (for example, 20c) is required to maintain the rear end in an insulating state with respect to the inside of the accommodating recess 13.
m), the high voltage applied to the machine body 4 housed in the housing recess 13 leaks to the earth body such as the robot arm that supports the rear end of the housing 12 because it is formed of the insulating material. There is no.

[0026]

As described above, according to the present invention, a machine body to which a high voltage is applied is housed in a bucket-shaped insulating housing, and the insulating housing is formed with an airtight housing recess for housing the machine body. In addition, since the outer peripheral surface is formed of an insulating material over at least the required insulation length,
Even if the rear end of the insulating housing and the airframe are not separated by the required insulation length, the outer rear end of the insulating housing can be kept insulated from the airframe in the accommodating recess, and thus the entire device can be maintained. It has an effect that it can be made compact and downsized, and at the same time, leakage of high voltage can be prevented.

Further, since the paint flow passage communicating with the paint supply pipe for supplying the paint to the rotary atomizing head is formed on the side wall of the insulating housing, the paint flow passage is formed without bypassing the paint hose. The paint can be supplied to the rotary atomizing head by simply connecting it to the opening on the rear end side, and therefore the paint hose is connected to the rear end side of the electrostatic coating machine, so that the posture of the electrostatic coating machine can be maintained. Even when changing, the paint hose does not get in the way, the electrostatic coating machine does not become large in the radial direction, and there is an effect that the piping process is extremely simple.

[Brief description of drawings]

FIG. 1 is a sectional view showing a multicolor electrostatic coating device according to the present invention.

FIG. 2 is a sectional view showing another embodiment.

FIG. 3 is a sectional view showing another multicolor electrostatic coating machine according to the present invention.

FIG. 4 is a rear view thereof.

FIG. 5 is a flow sheet showing a conventional device.

FIG. 6 is a flow sheet showing a conventional device.

[Explanation of symbols]

 1 ... Multicolor electrostatic coating machine 2 ... Rotating atomizing head 3 ... Air motor 4 ... Machine body 5 ... Tubular rotating shaft Np ... Thin tubular nozzle (paint supply pipe) Uv ...・ Valve unit 10 ・ ・ ・ Paint flow path 12 ・ ・ ・ Insulating housing 13 ・ ・ ・ Accommodation recess 13a ・ ・ Outer rear end 13b ・ ・ Inside the accommodating recess 14 ・ ・ ・ Side wall 15 ・ ・ ・ Paint flow Lines 15a, 15b ... Openings 16 ... Paint flow path 17 ... High voltage generator Uc ... Connection unit Up ... Piping unit 20 ... Piping unit side wall 24 ... High voltage Generator

Claims (5)

[Claims] 1. The rotary atomizing head (2) is supplied with each color paint into a tubular rotary shaft (5) of an air motor (3) which rotationally drives the rotary atomizing head (2) to which a high voltage is applied. In a multicolor electrostatic coating machine with a paint supply pipe (Np) inserted through it,
The rear end side of the machine body (4) consisting of the rotary atomizing head (2) and an air motor (3) for rotationally driving the head is housed in a bucket-shaped insulating housing (12), and the insulating housing (12) is the machine body. An accommodation recess (13) for accommodating (4) is formed airtight, and an outer rear end portion (13a) of the accommodation recess (13) can be maintained in an insulating state with respect to the inside (13b) thereof. At least an outer peripheral surface of the insulating housing (1
The side wall (14) of (2) is formed with a plurality of paint flow passages (15) penetrating along the longitudinal direction thereof, and an opening communicating with the paint hose at the rear end side of the paint flow passage (15). (15a) is formed, and an opening (15b) communicating with the rear end side of the paint supply pipe (Np) is formed on the front end side of the multicolor electrostatic coating machine. 2. A paint supply pipe (Np) for supplying each color paint to the rotary atomizing head (2) in a tubular rotary shaft (5) of an air motor (3) which rotationally drives the rotary atomizing head (2). In the multi-color electrostatic coating machine in which is inserted, the rotary atomizing head (2)
And the rear end side of the machine body (4) including the air motor (3) for rotating the same is housed in a bucket-shaped insulating housing (12), and the insulating housing (12) is a housing recess for housing the machine body (4). (13) is formed airtight, and at least its outer peripheral surface has a required insulation so that the outer rear end (13a) of the accommodating recess (13) can be insulated from the inner (13b). A tubular piping unit (Up), which is formed of an insulating material over its length and whose peripheral wall portion is formed of the insulating material over at least the required insulating length, is externally mounted on the insulating housing (12). Up), a plurality of paint flow passages (15) are formed so as to penetrate along the longitudinal direction thereof, and the paint flow passages (15)
An opening (15a) communicating with the paint hose is formed on the rear end side, and an opening (15b) communicating with the rear end side of the paint supply pipe (Np) is formed on the front end side thereof. Is a multicolor electrostatic coating machine. 3. The multicolor electrostatic coating according to claim 1, wherein a high voltage generator (17) for applying a high voltage to the rotary atomizing head (2) is embedded in the insulating housing (12). Machine. 4. The high voltage generator (24) for applying a high voltage to the rotary atomizing head (2) is mounted along the side wall (14) of the insulating housing (12). Multicolor electrostatic coating machine described. 5. A plurality of paint passages (10) communicating with the rear end side of the paint supply pipe (Np) are formed, and the paint supply pipe (Np) is provided through each paint passage (10). A plurality of valves (V) or paint supply pipes (N) for selectively supplying each color paint to the
A valve unit (Uv) having a valve drive unit for opening and closing a valve formed in p) is attached to the back side of the body (4), and the valve unit (Uv)
The paint flow inlet (10a) of the paint flow passage (10) is formed in the outer peripheral portion (11) of the paint flow passage (10), and the paint flow passage (15) formed in the insulating housing (12) or the piping unit (Up) Between the front end side opening (15b) and the paint inlet (10a) formed in the valve unit (Uv), there is a connection unit (Uc) formed with a number of paint flow paths (16) connecting these. The multicolor electrostatic coating device according to claim 1, wherein the multicolor electrostatic coating device is interposed.