JP4114832B2 - Electrostatic painting gun using a rotary atomizing head - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In the present invention, a bell-shaped atomizing head having an abutting portion formed on the inner periphery and a paint reservoir on the rear side of the abutting portion is fixed to the outer periphery of the distal end of a hollow shaft that rotates at high speed by driving an air turbine. Then, the paint supplied from the paint supply pipe passing through the hollow shaft to the paint reservoir in the atomizing head is sent to the front side of the atomizing head from the through hole formed in the abutting portion, and the atomizing head rotates. The present invention relates to an electrostatic coating gun using a rotary atomizing head in which a paint is atomized by the action of an electrostatic field formed between the centrifugal force generated by the liquid and an object to be coated and discharged toward the object to be coated.
[0002]
[Prior art]
The conventional electrostatic coating gun using a bell-shaped rotary atomizing head is made of a metal atomizing head and is charged with paint particles discharged from the atomizing head when a high voltage is applied thereto. It has become.
[0003]
[Problems to be solved by the invention]
Therefore, there is a problem that the electrostatic capacity of the atomizing head is large, and when it comes close to an object to be coated or other grounded object, a spark is generated and a fire or electric shock is likely to occur.
[0004]
[Means, actions and effects for solving the problems]
As a means for solving such problems, the present invention connects the paint supply pipe made of a conductive material to a high voltage generator, makes the atomizing head made of a non-conductive material, and abuts the atomizing head. Since the needle-shaped electrode with the rear end facing the paint supply pipe outlet and the tip facing the inner space of the atomizing head is attached to the center of the unit, the electrostatic capacity of the atomizing head is small, There is no risk of sparking even if an object approaches the object to be painted or other grounded objects, and the paint discharged from the atomizing head passes through the paint supply pipe connected to the high voltage generator through the paint. The electrode is charged when a high voltage is applied to the electrode.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIG.
In the figure, reference numeral 1 denotes a synthetic resin body, in which pressurized air supplied from the rear part thereof is supplied to the inner periphery of the air bearing 2 so that the hollow shaft 3 is freely supported and attached to the rear part. The air turbine 4 is rotationally driven at a high speed, and an atomizing head 5 made of a non-conductive material such as a bell-shaped synthetic resin is attached to the tip of the hollow shaft 3 and is attached to the rear end. Is provided with a paint opening and closing valve 7 which opens and closes by the advancement and retraction of the valve rod 8.
[0006]
An abutting portion 51 is integrally formed on the inner periphery of the atomizing head 5, and a paint reservoir 53 is formed on the rear side of the abutting portion 51. The paint reservoir 53 communicates with the inner surface front of the atomizing head 5 through the hole 52.
[0007]
A paint supply pipe 6 made of a conductive material is inserted into the hollow shaft 3, and the tip faces the rear side of the abutting portion 51 in the atomizing head 5.
[0008]
At the center of the abutting portion 51 of the atomizing head 5, a needle-like electrode 54 with the rear end facing the outlet of the paint supply pipe 6 and the front end facing the inner space of the atomizing head 5 is attached. Yes.
[0009]
When the high voltage generator 9 built in the main body 1 is connected to the paint supply pipe 6 and the on-off valve 7 is opened and the liquid paint flows through the paint supply pipe 6, the paint supply pipe 6 is passed through the liquid paint. A negative high voltage is applied from the electrode 54 to the electrode 54 and once accumulated in the paint reservoir 53, the liquid paint flowing through the through hole 52 and in front of the inner surface of the atomizing head 5 is charged to a negative high potential and rotated at high speed. It is atomized by the action of a high-potential electrostatic field formed between the centrifugal force generated by the atomizing head 5 and a grounded workpiece (not shown), and is adsorbed on the workpiece.
[0010]
As described above, since the electrode 54 is accommodated in the hollow of the atomizing head 5 made of a non-conductive material, there is no possibility that the electrode may come close to an object to be coated or other grounded object and a spark may be generated. It is.
[0011]
Note that the voltage of the paint supply pipe 6 can be transmitted to the electrode 54 as long as it is a paint having a resistance value of 100 MΩ or less normally used for electrostatic coating.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an embodiment of the present invention.
[Explanation of symbols]
3: Hollow shaft 4: Air turbine 5: Atomizing head 6: Paint supply pipe 51: Butting part 52: Through hole 54: Electrode

Claims (1)

A bell-shaped atomizing head, which is formed with an abutting portion on the inner periphery and has a paint reservoir behind the abutting portion, is fixed to the outer periphery of the tip of a hollow shaft that rotates at high speed by driving an air turbine. The paint supplied to the paint reservoir in the atomizing head from the paint supply pipe passed through the shaft is sent to the front side of the atomizing head from the through hole formed in the abutting portion, and the atomizing head rotates. In the electrostatic coating gun using a rotary atomizing head in which the coating material is atomized by the action of an electrostatic field formed between the centrifugal force and the coating material and discharged toward the coating material, the coating material supply The pipe is made of a conductive material and connected to a high voltage generator, the atomizing head is made of a non-conductive material, the center of the abutting portion of the atomizing head, and the rear end at the outlet of the paint supply pipe A needle-shaped electrode with the tip facing the inside of the atomizing head was attached. Electrostatic spray gun with a rotary atomizing head according to claim.

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