JPS5939357A - Apparatus for electrostatically coating wire body - Google Patents

Abstract

PURPOSE:To improve the coating efficiency and the uniformization of a coating agent, by a method wherein fine particles of the coating agent sprayed from an electrostatic sprayer are confined in a chamber comprising an insulating material and a wire body is run through the chamber. CONSTITUTION:A wire body 4 advances toward a passing port 1c through a chamber 2 along a running direction A from a passing port 3a and coated with a coating agent during this time by an electrostatic sprayer 7. That is, because an ionized zone is formed at the periphery of the needle electrode 7b of the electrostatic sprayer 7 and electric lines of force E are formed between said electrode 7b and the wire body 4 by applying high voltage to said electrode 7b, fine particles of the coating agent sprayed from the head part 7a thereof are charged to be applied to the wire body 4. In addition, the chamber 2 is formed of an insulating material such as nylon or glass and charged to potential with same polarity as that of the fine particles of the coating agent, both of them are mutually repelled to promote the coating of the fine particles to the wire body 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrostatic coating device for a linear body that is capable of uniformly applying a coating agent to the entire circumference of a thin linear body and that increases coating efficiency.

Conventionally, in order to apply atomized coating agent fine particles to a thin linear body with a wire diameter of about 0.05 to 50 gm, an electrostatic or air atomizer was used in a large coating booth. The linear body was arranged perpendicularly to the traveling direction, and the coating work was performed while the linear body was traveling at a predetermined speed. Since the wire diameter of the linear body is much smaller than the coating width and turn width of the sprayer, the coating efficiency is extremely low. Second, if the coating agent particles do not fly at right angles toward the linear body, the coating agent particles will scatter toward the inner wall surface of the coating booth, causing a mess inside the coating booth. However, there was a drawback that it was difficult to recover the wasted coating agent. Thirdly, in the conventional technology, in order to obtain a film with a uniform width of m around the entire circumference of the linear body, it is necessary to install multiple sprayers in the coating booth, and the equipment is It had the disadvantage of being complex and bulky.

The purpose of the present invention is to improve the drawbacks of the prior art coating apparatus for linear objects as described above. By running one or more linear bodies in the chamber, the coating agent can be uniformly applied to the entire circumference of the linear bodies, and the coating efficiency can be increased. The present invention provides an electrostatic coating device for linear objects.

In order to achieve the above object, the present invention has a configuration that includes a chamber formed in a cylindrical shape to confine fine particles of coating agent therein, and a chamber configured to spray charged fine particles of coating agent into the chamber. an electrostatic '9it fogger provided facing inside, the chamber is formed of an insulating material, and the chamber is charged to the same potential as the charged coating agent particles. The reason is that

In this way, by forming the chamber from an insulating material and placing the chamber in an atmosphere surrounding the charged coating agent particles,
Since the chamber can be given a force to repel the coating agent fine particles from the potential inner wall toward the linear body, the effect of confining the coating agent fine particles in the chamber can be further enhanced. Therefore, the electrostatic attraction force due to the electrostatic field formed between the electrostatic sprayer and the linear body in the chamber causes the coating agent fine particles trapped within the range of the electrostatic attraction force to be transferred to the linear body. The coating can be applied without waste, increasing coating efficiency, and staining of the inner wall of the chamber can be prevented.

Here, in the present invention, the linear body may be, for example, i1′ brass wire, iron wire, or a metal wire such as a screw thread thereof, a thread, a resin wire such as a wire, a glass wire such as an optical fiber, The cross-sectional shape is expressed as a concept including circular, square, plate-like, etc. In addition, coating agents include solvent paints such as amino alkyd, acrylic, epoxy, and polyurethane paints, non-aqueous ice version paints, vinelid paints, water-based paints, powder paints, etc., as well as ultraviolet 11M curable paints and electron beam curable paints. This includes hardening paint, oil at the linear body passage port, etc. Furthermore, as an electrostatic sprayer, a ridge-type type can be used as long as it can charge the particles of the coating agent by applying a high voltage. For example, a rotating sprayer using centrifugal force can be used. We have a head type electrostatic sprayer, an airless electrostatic sprayer that uses liquid pressure, an air atomization type electrostatic sprayer that uses atomizing air, an ultra-backwave type electrostatic sprayer that uses ultrasonic atomization, etc. Defined as including.

The present invention will be described below along with embodiments shown in the drawings.

In the figure, 1 is a chamber made of a cylindrical body arranged so that its axis is perpendicular, and the chamber 1 normally has an insulating property and is initially charged to the same polar potential in an atmosphere where a charged body is present. A chamber 2 is formed inside the oil pad, which is made of a synthetic resin material such as nylon or Teflon, or an insulating material such as glass or ceramic. Upper part 11 of said chamber 1! l1a is attached to a lid 3 having a linear body passage port 3a, and a linear body passage port IC that also serves as a coating agent outflow prevention wall is formed on the lower side 1b, and a linear body passage port IC is formed in the horizontal direction. A flange portion 1d is formed by bending.

Reference numeral 4 indicates a linear body (only one is shown in the drawing) to which a coating agent is applied in the chamber 2, and the linear body 4 is a linear body such as a wire assembly manufacturing device, an optical fiber manufacturing device, etc. Manufactured by the manufacturing device 5.

Reference numeral 6 denotes a guide roller placed at ground potential, and the linear body 4 manufactured as described above is guided by the guide roller 6. The coating agent is applied within the chamber 2 while the robot moves in the traveling direction shown by arrow A in the figure.

Reference numeral 7 denotes an electrostatic sprayer fixedly installed above the chamber 1, and the IW electrosprayer 7 connects to a coating agent tank 12 via an air refiner 11, and to an air source 14 via an air hose 13. are connected to each other. The head part 7a of the electrostatic jet ejector 7 is provided obliquely in the running direction A facing into the chamber 2, that is, facing downward 11b, and a high voltage is applied to the needle-like electrode 7b at the tip of the head part 7a. By applying a high voltage from the generation source 9, an ionization upper region is formed around the needle electrode 7b, and an electrostatic field is formed between the guide roller 6 and the linear body 4 at ground potential. do. Further, the coating agent jetted from the head portion 7a is atomized by the atomizing air from the air source 14, and while the coating agent fine particles pass through the ionization upper region, they are charged, and the static electricity between them and the linear body 4 increases. It flies along the electric field lines E due to the electric field,
The charged coating agent fine particles are applied to the linear body 4.

Further, 15 indicates an exhaust pipe connected to the flange portion 1d on the lower side 1b of the chamber 1, and the exhaust pipe 15 is also made of the same material as the chamber 1, such as a resin material such as nylon or Teflon, or an insulating material such as glass or ceramic. It is made of wood. One side of the exhaust pipe 15 has 7 tank parts 1
The flange part 15a is connected to the flange part 15a, and the other side is the exhaust port 15b.
The coating agent is collected by depositing the coating agent from the exhaust port 5a toward the exhaust port 15b.The coating agent recovery plate 16, which is grounded, the coating agent separation filter 17, and the fan 1.
8 are provided respectively. On the other hand, the exhaust pipe 15 is provided with a coating agent recovery pipe 19 located near the jam plate 16.
The coating agent collected by the coating agent fine particles adhering to the scraping plate 16 is transferred to the tank 20 via the coating agent collection pipe 19.
collected and reused.

Furthermore, 21 is a drying chamber provided at the next stage of the chamber 1, and the drying chamber 21 is a linear body 41r coated with a coating agent in the chamber 1, and is used for baking and drying. A drying source 22 is provided, and a fan 23 is provided in the exhaust duct 21a.

Here, as the drying source 22, a heat source such as a heater is used when the coating agent is a solvent paint, an ultraviolet generating source is used when the coating material is an ultraviolet curing type paint, and an ultraviolet source is used when the coating agent is an electron beam curing type paint. An electron beam source is used. The linear body 4 from the linear body passing port IC of the chamber 1 is completely dried while passing through the drying chamber 21, and is wound up by the winding device 24 provided next to the chamber 21. It is configured as follows.

Although the present invention is configured as described above, the linear body manufacturing apparatus 5
The linear body 4 manufactured by
It passes through the chamber chamber 2 from the linear object passage port 3& while being guided by the linear object passage port 3&, exits from the linear object passage port IC, passes through the drying chamber 21, and is wound up by the winding device 24. During this time, when the linear body 4 passes through the chamber 2 along the traveling direction A, the electrostatic sprayer 7 applies the coating agent.

That is, by applying a high voltage to the needle-shaped electrode 7b of the electrostatic sprayer 7, an ionization upper region is formed around the sword-shaped electrode 7b, and lines of electric force E are generated between the needle-shaped electrode 7b and the linear body 4. As a result, the coating agent fine particles sprayed from the head portion 7a are charged while passing through the ionization upper region, and are applied to the linear body 4 after flying along the lines of electric force E. Then, the linear body 4' coated with the coating agent is dried and baked with the coating agent by the drying channels 21, and the linear body 4' coated with the coating agent is wound up in the winding device 24. It will be done.

On the other hand, the coating agent fine particles that have not been applied to the linear body 4 are sucked toward the exhaust port 15b side of the exhaust pipe 15 by the fan 18. During this time, the particles of the coating agent adhere to the grounded friction plate 16, grow and fall, and flow from the coating agent collection pipe 19 to the tank 20.
The remaining coating agent fine particles are removed by the filter 17, and the cleaned exhaust gas is discharged outdoors through the exhaust port 15b. By applying a voltage of a different polarity to the coating agent fine particles to the interference plate 16, the recovery efficiency of the coating agent can be further increased.

Furthermore, since the chamber 1 is made of insulating materials such as nylon, Teflon, glass, and ceramics, these insulating materials are The potential is the same polarity as the potential of the coating agent fine particles, for example, if the coating agent fine particles are negatively ionized,
Negatively charged.

As a result, the inner wall of the chamber 1 and the particles of the coating agent repel each other, which further enhances the confinement effect within the chamber 2 and improves the coating efficiency on the linear body 4. On the other hand, since the particles of the coating agent are repelled from the inner wall of the chamber 1, it is also possible to prevent the inner wall of the chamber 1 from being contaminated by the coating agent.

Next, regarding the shape of the chamber 1, the inside of the chamber 2 is set within the range of effective electrostatic attraction, and as many particles of the charged coating agent confined within the chamber 2 as possible are transferred to the linear body 4. It is desirable to apply it. Therefore, in the present invention, the voltage applied to the needle electrode 7b is set to ±5 to 9.
When setting it to 0 kV, the inner diameter of chamber 1 is 800jIi.
If the longitudinal length of the flat body 4 along the running direction A is equal to or more than 300 tpr, the inside of the chamber 2 will be affected by the lines of electric force E due to the electrostatic field.

As a result, all of the coating agent fine particles confined within the chamber 2 can fly and be applied to the linear body 4 along the lines of electric force E. In this way, in the present invention, the shape of the chamber 1 can be set within the range of effective electrostatic attraction, so that waste of the coating agent can be reliably prevented and the production efficiency can be improved. .

Furthermore, by arranging the head portion 7a of the electrostatic sprayer 7 obliquely so as to face downstream of the running direction A of the linear body 40, the electric force along the running direction A can be applied as shown in the figure. The coating agent can be applied uniformly.

Although the chamber 1 is described as a cylindrical body in the above-described embodiment, it may be a square cylindrical body, or the chamber 1 and the exhaust pipe 15 may be integrally formed. Also,
Although the chamber 1 has been described as being provided vertically so that the linear body 4 runs from above to below, the chamber 1 may be provided so that the axial direction thereof is horizontal. Further, although it has been described that the linear body 4 is brought to earth potential by the guide roller 6, it may be replaced with a brush or the like, and if the linear body manufacturing apparatus 5 itself can be brought to earth potential, the guide roller 6 may be brought to earth potential. Row 26 can be made unnecessary.

Experimental Example A polypropylene container with an inner diameter of 60mm and a length of 5001m was used as the chamber 1, and the electrostatic sprayer 7 had an applied voltage of ±18 kV, a coating agent discharge rate of 3 ce/min, and an atomizing air pressure of 1. Using an air atomization gun of Okg/cWL, a quartz glass wire with a diameter of 0.2 mm was run as the wire body 4 in the chamber 1 at a running speed of 601 V/fr11n to carry out the coating operation. As a result, we were able to obtain approximately 50 times the coating efficiency compared to the conventional technology, in which the air purifying gun was placed perpendicularly to the linear object in the coating booth. The electrostatic coating device for linear objects according to the present invention is as described in detail above, and sprays charged coating agent fine particles into a chamber formed of an insulating material, and runs the linear object into the chamber. Since the structure is configured such that fine particles of the coating agent are applied to the linear body during the heating process, the fireflies inside the chamber 1! The coating agent fine particles can bring the chamber to the same potential as the potential of the fine particles, thereby increasing the confinement effect within the chamber. Therefore, coating agent fine particles within the range of electrostatic attraction force can be coated without waste, and the coating efficiency can be greatly improved. Furthermore, it is possible to prevent the coating agent from adhering to the inner wall of the chamber, thereby preventing the inner wall of the chamber from being contaminated. Furthermore, even if the coating agent is sprayed unevenly in the running direction of the linear body, the coating agent fine particles are uniformly dispersed in the chamber, so the thickness of the coating film on the linear body can be made uniform. can. Furthermore, by selecting the shape of the chamber so that the entire interior of the chamber is influenced by the silent IJL field, the particles of coating agent in the chamber can be well coated on the linear body, compared to the conventional technology. It has many excellent effects such as being able to significantly reduce the recovery ratio of the coating agent.

[Brief explanation of the drawing]

The figure is a system diagram showing an electrostatic coating device for linear objects according to the present invention.

Claims (3)

[Claims] (1) A chamber formed in a cylindrical shape to confine coating agent fine particles therein, and an n'fIL provided facing into the chambers so as to spray the charged coating agent fine particles into the chambers. a sprayer, and the chamber is formed of an insulating material, and the chamber/? A static 1r coating device for a linear body, which is configured to charge the particles to the same polar potential as the charged coating agent fine particles. (2) The insulating material is a synthetic resin such as nylon or Teflon, or an insulating material such as glass or ceramic. (3) i1 for a linear body according to claim (1), wherein the linear body is held at a ground potential? Electrocoating equipment.