JP2000033292A - Electrostatic coating gun with rotary atomizing head - Google Patents

Abstract

(57) [Summary] [PROBLEMS] A conventional electrostatic coating gun using a rotary atomizing head is:
After the paint supplied from the paint supply pipe temporarily accumulates in the paint reservoir formed at the rear part of the atomizing head, it is sent to the front side of the atomizing head from the through hole formed in the abutting part by centrifugal force. Therefore, there is a problem that the paint overflowing from the paint pool passes between the paint supply pipe and the hollow shaft, enters the air turbine driving the hollow shaft, and causes malfunction. SOLUTION: Since an enlarged diameter step is formed on the inner periphery near the tip of the hollow shaft and a through hole is formed from the largest diameter portion of the enlarged diameter portion to the outer periphery of the hollow shaft, the paint overflowing from the paint pool is formed. Is discharged to the outer periphery of the hollow shaft through the through hole by centrifugal force, and is prevented from entering the air turbine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow head having a bell-shaped atomizing head having a striking portion formed on an inner periphery thereof and having a paint reservoir behind the striking portion, which is rotated at a high speed by driving an air turbine. It is fixed to the outer circumference of the tip of the shaft, and the paint supplied to the paint reservoir in the atomization head from the paint supply pipe that passes through the hollow shaft is sent out to the front side of the atomization head from the through hole formed in the abutting part. A rotating atomizing head which atomizes the paint by the action of the electrostatic field formed between the centrifugal force generated by the rotation of the atomizing head and the object to be coated and discharges it toward the object to be coated. Related to electropaint guns.

[0002]

2. Description of the Related Art In a conventional electrostatic spray gun using a bell-shaped rotary atomizing head, the paint supplied from a paint supply pipe temporarily accumulates in a paint reservoir formed behind the atomizing head as described above. After that, the air is sent to the front side of the atomizing head from a through hole formed in the abutting portion by centrifugal force.

[0003]

Therefore, when the amount of paint supplied to the atomizing head is large, not all of the paint can be stored in the paint pool, and the paint overflowing from the paint pool is connected to the paint supply pipe. There is a problem in that a malfunction occurs due to intrusion into an air turbine that drives the hollow shaft through the space between the hollow shafts.

[0004]

According to the present invention, as a means for solving the above-mentioned problems, a diameter increasing step is formed on the inner periphery near the tip of the hollow shaft, and the diameter increasing step is provided. Since a through hole was formed from the largest diameter part to the outer periphery of the hollow shaft,
This has the effect of preventing the paint overflowing from the paint pool from being released to the outer periphery of the hollow shaft through the through hole by centrifugal force and entering the air turbine.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, reference numeral 1 denotes a synthetic resin main body. Pressurized air supplied from the rear portion is supplied to the inner periphery of the air bearing 2 so that the hollow shaft 3 is rotatably supported and attached to the rear portion. The hollow shaft 3 has a bell-shaped atomizing head 5 attached to the tip of the hollow shaft 3.

[0006] On the inner periphery of the atomizing head 5, an abutting portion 51 is provided.
Are formed integrally, and a paint pool 53 is formed behind the abutting portion 51 so that the abutting portion 5 is formed.
The paint reservoir 53 communicates with the front of the inner surface of the atomization head 5 by the through hole 52 formed in the first hole 1.

A paint supply pipe 6 is inserted through the hollow shaft 3, the tip of the paint supply pipe 6 faces the inside of the atomizing head 5, and a paint opening / closing valve 7 that opens and closes by the advance and retreat of a valve rod 8 is provided at the rear end. Have been.

As described above, the configuration is the same as that of a conventionally known electrostatic coating gun using a rotary atomizing head. The high voltage generator 9 built in the main body 1 is connected to the paint supply pipe 6 by a conducting wire 11. A negative high voltage is generated when the liquid paint flowing into the paint supply pipe 6 comes into contact with the electrode 10 when the on-off valve 7 opens and is connected to the electrode 10 made of a metal cylinder fitted to the rear part of the inner peripheral surface. After being applied and temporarily stored in the paint pool 53, the through holes 5
2 through the atomizing head 5, which flows into the front of the inner surface of the atomizing head 5, and is atomized by the action of the high-potential static electric field formed between the centrifugal force by the atomizing head 5 rotating at high speed and the grounded object (not shown). In this embodiment, a conical enlarged diameter step 31 is formed on the inner periphery near the tip of the hollow shaft 3, and the hollow shaft is formed on the largest diameter portion of the hollow shaft 3. A through-hole 32 is formed in the outer periphery of 3 and extends obliquely.

For this reason, the paint which overflows the paint reservoir 53 and flows toward the air turbine 4 through the space between the paint supply pipe 6 and the air turbine 4, travels through the enlarged diameter step portion 31 by centrifugal force, and the through hole 3.
2 is discharged to the outer periphery of the hollow shaft 3.

Accordingly, the paint overflowing from the paint reservoir 53 passes between the paint supply pipe 6 and the hollow shaft 3 and the hollow shaft 3
In addition, it is possible to prevent a situation in which an operation failure occurs due to intrusion into the air turbine 4 that drives the air conditioner, and it is possible to increase the supply amount of the paint, thereby improving the efficiency of the painting operation.
Since a large amount of solvent may be supplied at the time of washing, the time for color change can be reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

[Explanation of symbols]

 3: hollow shaft 4: air turbine 5: atomization head 6: paint supply pipe 31: enlarged diameter step 32: through hole 51: butting portion 52: through hole 53: paint pool

Claims (1)

[Claims] An abutment portion is formed on the inner periphery, and a bell-shaped atomizing head having a paint reservoir formed behind the abutment portion is provided on the outer periphery of the distal end portion of a hollow shaft rotating at a high speed by driving an air turbine. Fixed, and feeds the paint supplied to the paint reservoir in the atomization head from the paint supply pipe passed through the hollow shaft to the front side of the atomization head from a through hole formed in the abutting portion,
Electrostatic force using a rotary atomizing head configured to atomize the paint by the action of the electrostatic field formed between the centrifugal force due to the rotation of the atomizing head and the object to be coated and discharge it toward the object to be coated. In the coating gun, a rotating step is formed on the inner periphery near the tip of the hollow shaft, and a through-hole is formed from the maximum diameter portion of the expanding step to the outer periphery of the hollow shaft. Electrostatic coating gun using atomizing head.