JP2001110260A - Method and device for applying powder to linear body of electric wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for applying powder to a linear body of an electric wire, capable of uniformly applying power to the surface of the linear body while inhibiting the variation of separativeness of a coating. SOLUTION: A humidifying means 3 is provided at the front stage of a powder applicator 4 for humidifying a linear body 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for extrusion-coating a linear body such as a rubber or plastic electric wire, and more particularly to improving the releasability of the coating before extrusion-coating. The present invention relates to a method and an apparatus for applying powder to a linear body.

[0002]

2. Description of the Related Art In the case where a synthetic resin or the like is extrusion-coated on a linear body of a rubber / plastic electric wire, it is possible to prevent sticking between the linear body and the coating or between coatings in a double coating. To this end, a powder such as talc is applied as a release agent to the surface of the linear body, followed by extrusion coating.

With reference to FIG. 4, a conventional method and apparatus for extruding a powder after applying powder to a linear body will be described.

[0004] The linear body 2 travels to the right side in the figure, and after a powder such as talc is applied to its surface by a powder coating device 4, a coating 6 is extrusion-coated by an extruder 5. You.

When the amount of the powder applied to the linear body 2 is uneven, if the amount of the applied powder is small, the extruded coating 6 is easily stuck to the linear body. In order to apply the powder evenly, various devices have been devised.

[0006] Japanese Utility Model Publication No. 55-50886 discloses that a wire is passed through a separating agent in a coating tank, a drying device for drying the separating agent in the coating tank, and the separating agent is stirred. For example, Japanese Patent Publication No. 1-55725 discloses that a large number of vibrating members are disposed in a container filled with powder. No. -28735, a pressing roller for moving a cable core in a container filled with powder is provided,
It is disclosed that the press roller is swung by an arm. Japanese Utility Model Publication No. Hei 6-28736 discloses a press roller for running a cable core in a container filled with powder, and the press roller is swung by the arm. Move it,
Shaking the container is shown.

[0007]

However, in the above-described conventional coating method and apparatus, although the unevenness in the amount of powder applied is reduced, the unevenness still occurs, and the peeling property of the coating material is reduced. There was variation.

For this reason, when it is necessary to peel off the coating of the extrusion-coated electric wire, for example, for terminal treatment or the like, a phenomenon occurs that the wire cannot be easily peeled off where the amount of powder applied is small. In addition, the workability of stripping the coating was poor.

Accordingly, an object of the present invention is to solve the above-mentioned problems, to apply powder uniformly to the surface of a linear body, and to suppress variation in the peelability of a coating.
An object of the present invention is to provide a method and an apparatus for applying powder to a linear body of an electric wire.

[0010]

In order to achieve the above object, a first aspect of the present invention is a method of applying powder to a wire before extruding and coating the wire. After humidifying the body, the powder is applied to the linear body of the electric wire to which the powder is applied.

According to a second aspect of the present invention, there is provided an apparatus for applying powder to a linear body before extruding a plastic or the like onto the linear body of the electric wire, wherein the linear body is humidified before the powder coating apparatus. This is an apparatus for applying powder to a linear body of an electric wire provided with a humidifying means for performing the humidification.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a configuration diagram of an extrusion coating production line using an apparatus for applying powder to a wire linear body according to the present invention, and FIG. 2 is a diagram showing a humidifying means and a powder applying apparatus according to the present invention. It is a block diagram.

As shown in FIG. 1, the linear body 2 travels to the right in the figure, and after being humidified in the humidifying means 3, a powder coating device 4 applies powder such as talc to the surface thereof. Is applied, and the coating 6 is extrusion-coated by the extruder 5.

Next, the configuration of the humidifying means 3 and the powder coating device 4 will be described with reference to FIG.

The humidifying means 3 comprises a steam generator 7 for generating water vapor and a humidifying guide pipe 9 for guiding the linear body. The linear body 2 travels and moves in the humidifying guide pipe 9. The surface is humidified by the steam generated by the steam generator 7.

By keeping the amount of water generated by the steam generator 7 and the moving speed of the linear body 2 constant, the linear body 2 can be uniformly humidified.

The powder coating device 4 includes a container 12 filled with a powder 11 such as talc, and a stirring blade 13 for stirring the powder 11 in the container 12. 15 to the stirring blade 13.

Next, the operation of the present invention will be described.

The linear body 2 travels in the humidifying guide pipe 9 of the humidifying means 3 to uniformly humidify the surface, and then travels in the container 12 of the powder coating device 4 to be humidified. The powder is applied to the surface, and the coating 6 is extrusion-coated by the extruder 5.

Before the powder is applied to the surface of the linear body 2, the surface is uniformly humidified so that the powder can be applied evenly.

Here, in order to clarify the effects of the present invention, a cable extruded and coated using a method and an apparatus for applying powder after humidifying a linear body according to the present invention and a conventional method are used. An extruded cable was prepared and the peelability of the coating was measured and compared.

First, two cable cores of about 3φ covered with an insulator were twisted at a pitch of 100 to 150 mm, and the twisted cores were each extruded and coated with 100 samples by the method of the present invention and the conventional method. Produced.

The conditions for humidifying the sample produced by the method of the present invention are as follows: the amount of water generated by the steam generator is 5 cc / min, and the moving speed of the linear body is 40 m / min.
min.

FIG. 3 shows a method of evaluating the exfoliation property of a coating of an extruded sample.

As shown in FIG. 3, the drawing force was measured when only the twisted core 23 was pulled out in the direction of arrow A through the cutout 22 with the length L of the coating 21 of the sample 20 being 100 mm.

Table 1 shows the measurement results.

[0028]

[Table 1]

As is clear from Table 1, in the sample (conventional product) manufactured by using the conventional method, the pulling force at the time of pulling out the coating material varied in the range of 0.8 to 10.0 kg and 1.2 kg. On the other hand, in the sample (invention product) manufactured using the method of the present invention, the pulling force at the time of pulling is 0.8 to 1.0 kg, and the variation range is 0.2 kg.
g.

Regarding the upper limit value which causes a problem of peeling property, in the case of a sample manufactured by using the conventional method, the upper limit is 10.
In some samples, the weight was 0 Kg, and the coating was stuck to the twisted core, whereas in the samples produced using the method of the present invention, the upper limit of the pulling force was 1.0 Kg.
g, indicating that the coating did not stick to the twisted core and that the coating had good peelability.

That is, it can be seen that by applying the powder after uniformly humidifying the linear body, the unevenness of the applied amount of the powder can be suppressed and the coating does not stick.

[0032]

In summary, according to the present invention, the linear body is uniformly humidified and then the powder is applied to suppress the unevenness in the amount of the applied powder, and the variation in the peelability of the coated material after extrusion coating. Can be suppressed.

Further, since there is no place where the amount of applied powder is small, the coating is formed between the linear body and the coating,
There is no sticking between the coatings in the heavy coating, and the peeling workability is good.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an extrusion coating production line using an apparatus for applying powder to a wire linear body of the present invention.

FIG. 2 is a configuration diagram of a humidifying unit and a powder coating device according to the present invention.

FIG. 3 is a diagram showing a method for evaluating the peelability of a coating on a sample subjected to extrusion coating.

FIG. 4 is a configuration diagram of a conventional extrusion coating production line using an apparatus for applying powder to a linear body.

[Explanation of symbols]

 2 linear body 3 humidifying means 4 powder coating device 5 extruder

Claims (2)

[Claims] 1. A method of applying powder to a wire before extrusion coating the wire, wherein the powder is applied after humidifying the wire. A method of applying powder to a body. 2. An apparatus for applying powder to a linear body before extruding and coating the linear body of an electric wire, wherein a humidifying means for humidifying the linear body is provided in a stage preceding the powder coating apparatus. An apparatus for applying powder to a linear body of an electric wire.