JPH1034026A - Spotty pattern coating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating device by which a relatively large spotty pattern even in particle sizes is coated without wasting. SOLUTION: A tapered rotary tube body 4 has a bent part which is bent inward over the whole periphery of the end edge on the large diameter side thereof, and has one or more paint discharging holes 6 near the base of the bent part. Plurality rotary tube bodies 4 are coaxially fixed to a rotating shaft 3 arranged diagonally to the traveling direction above the traveling surface of a material (a) to be coated, and a paint feeding pipe 11 is made to face each rotary tube body 4 in the small diameter side thereof, and also a nozzle 13 for jetting pressurized air downward is arranged above the paint discharging holes 6 of each rotary tube body 4. Paint fed from the paint feeding pipe 11 flows along the inner peripheral surface of each rotary tube body 4 to the large diameter side by centrifugal force, and after it is accumulated in the corner part constituted of the rotary tube body 4 and the bent part, it is discharged in lines from the paint discharging holes 6 and is granulated by surface tension thereof and adheres to the material (a) to be coated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating apparatus for coating a relatively large and uniform spot pattern on an object to be coated.

[0002]

2. Description of the Related Art Conventionally, in order to paint a spotted pattern, paint supplied from above a rotary cylinder having a large number of vertical grooves formed on an inner peripheral surface is spread while sticking to the inner peripheral surface by centrifugal force. Although it was designed to fall down along the groove and to fly out as particles from the lip and apply it to the object to be coated, a rotating cylindrical body was used to paint a large spot pattern with a particle size of about 1 to 3 mm. It is necessary to reduce the rotation speed of the paint, and then the paint becomes a film after being released from the edge of the mouth and becomes a particle, so that the particle size greatly varies.

[0003] Further, since the paint is dropped down below the rotary cylinder in a circular shape, the paint is applied at a high density on both sides in the running direction of the object to be painted, so that only the paint in the central portion can be used. Furthermore, paint is discharged before the leading edge of the workpiece in the running direction enters the range where the paint can be dropped, and the paint is discharged until the trailing edge of the workpiece in the running direction is out of the range where the paint can be dropped. Otherwise, uniform painting cannot be performed,
A lot of paint wasted and was uneconomical.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a coating apparatus capable of coating a relatively large spot pattern having a uniform particle size without wasting paint.

[0005]

Means for Solving the Problems, Actions and Effects As means for solving the above-mentioned problems, the invention according to claim 1 is a method in which a taper is applied to bend inwardly around the entire periphery of the large-diameter end edge. A plurality of rotary cylinders, each having a portion formed therein and having one or a plurality of paint discharge holes formed near the base of the bent portion, are disposed obliquely to the running direction above the running surface of the workpiece. A nozzle that ejects pressurized air downwardly above the paint discharge hole of each rotating cylinder while fixing the coating pipe coaxially to the rotating shaft and facing the paint supply pipe to the small diameter side of each rotating cylinder. The paint supplied from the paint supply pipe flows to the large-diameter end side along the inner peripheral surface of the rotary cylinder by centrifugal force, and accumulates at a corner formed by the rotary cylinder and the bent portion. Is released from the paint discharge holes in a streak form and becomes granular due to surface tension. Since it is applied to the object to be coated, it is possible to uniformly apply a relatively large spot pattern, and each rotating cylinder has its rotating axis parallel to the running surface of the object to be coated and the direction of travel. Because it is inclined and has a nozzle that blows out pressurized air upward and downward,
The paint particles are sprayed onto the object to be coated in a band shape from each rotating cylinder without scattering the paint particles upward, and the inclination and interval of the rotating cylinder are adjusted so that the coating bands slightly overlap each other. This has the effect of applying the paint uniformly and efficiently. According to the second aspect of the invention, since the nozzle is a flexible hose, the pressurized air is rotated while swinging irregularly. Since the particles of the paint are more uniformly applied to the object to be sprayed on the cylindrical body, and the invention according to claim 3 has the cylindrical part protruding from the paint discharge hole, the discharged paint is applied to the outer periphery of the rotating cylindrical body. The particles adhere to the surface and are prevented from scattering as fine particles from the peripheral edge of the rotary cylinder, or from intermittently entering the paint and causing irregularities in the size of the paint particles.

[0006]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a conveyor for transporting an object to be coated a in the direction of an arrow.
, A plurality of rotating cylinders 4 are fixed horizontally at fixed intervals, and are driven to rotate in one direction by a motor (not shown).

As shown in FIG. 2, the rotary cylinder 4 has a tapered shape that expands on the left side, has a bent portion 5 that is bent inward at the left end edge, and has one piece at the base thereof. The paint discharge holes 6 are formed horizontally.

A holding ring 8 having a plurality of through holes 7 formed on the left side thereof is fitted on the inner periphery of the rotary cylinder 4, and a holding plate 9 is provided.
Together with the rotating shaft 3.

A paint supply pipe 11 is inserted into an opening 10 on the right side of the rotary cylinder 3, and the paint dropped from the tip of the pipe 11 falls on the slope of the holding ring 8 and passes through the through hole 7 by centrifugal force. After flowing to the left on the inner peripheral surface of the body 3 and accumulating at the corners of the bent portion 5, it is discharged to the outside through the paint discharge holes 6.

The released paint a is, as shown in FIG.
Initially, it forms a streak, and is formed into a granular shape by the surface tension and is swung in a circular shape, and the rotating cylinder 4 is inclined with respect to the traveling direction of the workpiece a. It is sprayed in a belt shape with a constant width, and it is possible to uniformly coat without gaps and with a small overlap by appropriately selecting the angle of the rotating body 4 with respect to the workpiece a and the mounting interval with respect to the rotating shaft 3. Can be.

A pressurized air supply pipe 12 is provided above the rotary shaft 3 in parallel with the rotary shaft 3, and a nozzle 13 made of rubber-like flexible hose is provided above the paint discharge hole 6 of each rotary cylinder 4.
Are downwardly branched, and irregularly oscillate by the ejection of the pressurized air so that the pressurized air ejects the paint particles, which are ejected upward, to be applied to the object to be painted a downward.

FIG. 3 shows a rotary cylinder 4 in which a large number of paint discharge holes 6 are formed to increase the discharge amount, and FIG. 4 shows a tapered cylindrical portion 14 on the outer surface of the paint discharge hole 6. This shows the formed rotary cylinder 4 in which the discharged paint adheres to the outer peripheral surface of the rotary cylinder 4 and scatters as fine particles from the periphery of the rotary cylinder 4 or intermittently enters the paint. The irregular size of the paint particles is prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view of one embodiment of the present invention.

FIG. 2 is an enlarged sectional view of the rotary cylinder.

FIG. 3 is a perspective view of another embodiment of the rotary cylinder.

FIG. 4 is a cross-sectional view of another embodiment of the rotary cylinder.

[Explanation of symbols]

 3: rotating shaft 4: rotating cylinder 5: bent portion 6: paint discharge hole 11: paint supply pipe 12: pressurized air supply pipe 13: nozzle a: workpiece

Claims (3)

[Claims] 1. A plurality of taper-shaped bent portions that are bent inward around the entire periphery of the large-diameter side edge, and one or more paint discharge holes are formed near the root of the bent portion. The rotating cylinders are fixed coaxially to the rotating shafts disposed obliquely to the traveling direction above the running surface of the object to be coated, and the paint supply pipe faces the small diameter side of each of the rotating cylinders, A speckled pattern coating apparatus in which nozzles for ejecting pressurized air downward are provided above the paint discharge holes of the rotary cylinders. 2. The spot pattern coating apparatus according to claim 1, wherein the nozzle is a flexible hose. 3. The spot pattern coating apparatus according to claim 1, wherein a cylindrical portion protrudes from the paint discharge hole of the rotary cylindrical body.