JP2000067673A - Manufacture of wire protecting member and device used in the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for continuously and efficiently manufacturing a well workable wire protecting member and a device used in this method. SOLUTION: A synthetic resin P in a semi-melted condition extracted out of a die for an extruder are fed into a plurality of forming dies 31-34 arranged in a water tank 2 at preset spaces in sequence and gradually drawn into a rolled form, and cooled by a water in the water tanks 2A, 2B, 2C. As a result, the inner and outer periphery faces of the synthetic resin P are cooled with a temperature difference and a wire protecting member in the rolled form is free from winding characteristics due to inside residual stress.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a wire protection member attached around an overhead distribution line mainly for protecting the overhead distribution line, and an apparatus used in the method.

[0002]

2. Description of the Related Art In general, an insulated wire is used as an overhead distribution wire, but the covering around the insulated wire is exposed to various outdoor environments, and a tension when the wire is installed on a utility pole or a steel tower. Is liable to be damaged or is constantly exposed to the high voltage of the power transmission, so that it is easily damaged.

[0003] Therefore, there are places where workers may touch.
For example, in the vicinity of a power pole or a steel tower for laying an electric wire, an electric wire protection member formed of an insulating material is attached around the electric wire.
This electric wire protection member is formed in a band shape or a cylindrical shape with a part of the periphery open with rubber or an elastomer resin, and is fixed by metal fittings in a state where the electric wire is wound. It is attached to.

Here, heretofore, this kind of electric wire protection member has been manufactured by extrusion molding or injection molding.

[0005]

In the above-mentioned conventional method for manufacturing an electric wire protection member, first, since extrusion can be performed continuously, the efficiency of production operation is high. However, the electric wire protection member manufactured by this method is high. Is a belt-shaped material and has elasticity, so that it is difficult to wrap and fix it around an electric wire by itself, and it is not possible to manufacture an electric wire protection member excellent in handleability. there were.

In addition, in the injection molding, an electric wire protection member which is curved in an arc shape so as to be easily covered with the electric wire can be manufactured. However, this method cannot continuously form the electric wire protection member. However, there is a problem in that the method requires an operation of making a notch in the vertical direction after molding, and the manufacturing operation efficiency is poor. Moreover, the wire protection member manufactured by this method is
There is also a problem that the object to be used is limited because it is limited to a fixed shape and size.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional method for manufacturing a wire protection member, and continuously and efficiently manufactures a wire protection member excellent in workability, and a method for using the method. It is intended to provide a device to be used.

[0008]

Means for Solving the Problems In order to solve the above problems, the invention according to claim 1 of the present invention relates to a method of manufacturing an electric wire protection member, and relates to a method of manufacturing a semi-molten material extruded from a die of an extruder. In this state, the elastomer or olefin-based synthetic resin is sequentially fed into a plurality of molding dies arranged at predetermined intervals in a water tank, and squeezed into a cylindrical shape in which a part of the periphery is overlapped. By gradually cooling and solidifying, the inner peripheral surface and the outer peripheral surface of the synthetic resin are cooled with a temperature difference, whereby the wire protection member formed into a roll is wound by the internal residual stress. It is characterized by having a habit.

Further, the invention according to claim 2 is an apparatus which is disposed between an extruder and a take-off machine and continuously manufactures a roll-shaped electric wire protection member with synthetic resin extruded from the extruder. A water tank, the inside of which is divided into a plurality of partitions, and a plurality of forming dies attached to the side walls of the water tank and the partition, the forming dies are provided with spiral openings, respectively, and The opening is set so that its diameter gradually decreases from the one located on the side of the extruder to the one located on the side of the take-off machine.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on illustrated embodiments.

FIG. 1 is a simplified sectional view showing an embodiment of an apparatus 1 used in the method for manufacturing an electric wire protection member of the present invention. This apparatus 1 is installed between an extruder (not shown) and a take-off machine (not shown). As shown in the figure, a water tank 2 having a plurality of divided inside walls 2b and 2c. Side walls 2a and 2d before and after (right and left sides in FIG. 1),
The molding dies 3 are located at the same height of the partition walls 2b and 2c.
1, 34, 32, and 33 are attached. Each of the molding dies 31 to 34 has a spiral opening 3.
1a to 34a (see FIG. 2). The openings 31a to 34a gradually decrease in the diameter of the spiral from the right side to the left side in FIG.
That is, the dimensions of the portions of the spiral that overlap in the circumferential direction (FIG. 2)
Is set to be large.

The water temperature in each of the water tanks 2A, 2B, 2C divided by the partition walls 2c, 2d is controlled so as to gradually decrease from the inlet side (right side) to the outlet side (left side).

Next, a method of manufacturing the electric wire protection member Pa of the present invention using the above-described apparatus 1 will be described. First, an extruder (not shown) installed on the inlet side (right side in FIG. 1) of the water tank 2 is used. The elastomeric or olefinic synthetic resin is heated and melted, and is extruded continuously in the form of a band or a curved band. Then, this is fed into the water tank 2A via the molding die 31. With this, the synthetic resin P in a semi-molten state extruded from the extruder is molded into a substantially cylindrical shape by the molding die 31, and is gradually cooled while passing through the water tank 2A. Is sent to the molding die 32. The molding die 32 is further narrowed down so that the degree of curvature is further increased, and the semi-solid synthetic resin P extruded from the extruder in this way passes through the water tanks 2A, 2B, 2C. In the meantime, the mixture is gradually cooled and solidified, and its shape is gradually adjusted by each of the forming dies 31, 32, 33, and 34, and is finally formed into a roll shape. At the left). And
The roll-shaped electric wire protection member Pa as shown in FIG. 3 is manufactured by cutting the drawn-out roll-shaped synthetic resin P at a desired position.

At this time, in the manufacturing method of the present invention, in the above-mentioned cooling process, the semi-molten synthetic resin P passes through the water tanks 2A, 2B, 2C in a rolled state. Although the outer peripheral surface contacts the large amount of water in the water tanks 2A, 2B, and 2C and is cooled relatively quickly, the water that has entered the inside of the roll is difficult to convection, and therefore, the water at this location is The synthetic resin P receives the heat when it is cooled, and is kept relatively high. As a result, the synthetic resin P wound in a roll shape is cooled with a temperature difference between the inner peripheral surface and the outer peripheral surface. When the internal and external temperatures reach an equilibrium state, the synthetic resin P thus cooled with a temperature difference between inside and outside causes residual stress due to thermal strain inside. Therefore, the wire protection member Pa formed in a roll shape in this way has a stronger property of maintaining this shape due to the winding habit due to the internal residual stress, and the original shape wound immediately into a roll shape even when unfolded. Try to return to.

As described above, according to the method of the present invention, the roll-shaped wire protection member P having a curl due to internal residual stress is provided.
a can be continuously produced by extrusion molding.

The electric wire protection member Pa manufactured in this manner is wound in a roll shape and pushes the both end portions Pa ′ and Pa ″ overlapping each other to cover the electric wire (not shown). Since the wire protection member Pa has a curl, the wire protection member Pa is wound around and held around the wire, so that the periphery thereof is not shown so as not to come off or move in this state. If it is fixed using a fixing bracket or the like, it can be easily attached to a desired position of the electric wire.

The electric wire protection member Pa manufactured by the method of the present invention as described above is attached to an electric wire and is used for preventing an electric leakage and an electric shock accident.

As described above, since the wire protection member Pa manufactured by the method of the present invention is formed by cutting an extruded material at a desired position, the wire protection member Pa having a desired length can be used. Since it can be easily obtained, and can be wound around the electric wire in a roll shape and attached, it is possible to cope with various conditions at the installation work site regardless of the difference in the diameter of the electric wire.

[0019]

As described above, according to the first aspect of the present invention, the roll-shaped wire protection member having a curl can be continuously manufactured by extrusion molding. There is an effect that an electric wire protection member excellent in workability can be continuously manufactured at low cost.

According to a second aspect of the present invention, there is provided an apparatus for manufacturing an electric wire protection member, comprising: a water tank having a plurality of inner walls divided by a partition; and a plurality of molding tanks mounted in a direction penetrating the water tank in a lateral direction. When the synthetic resin extruded from the extruder is formed into a roll and solidified, a curl due to residual stress can be simultaneously generated therein.

[Brief description of the drawings]

FIG. 1 is a simplified cross-sectional view showing an embodiment of an apparatus used in the manufacturing method of the present invention.

FIG. 2 is a simplified front view showing an embodiment of a molding die used in the manufacturing apparatus of the present invention.

FIG. 3 is a perspective view showing an example of an electric wire protection member manufactured by the method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electric wire protection member manufacturing apparatus 2, 2A, 2B, 2C Water tank 2a, 2d Side wall 2b, 2c Partition wall 31, 32, 33, 34 Molding dies 31a, 32a, 33a, 34a Opening

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koji Shingu 2-14-17 Sangenya, Taisho-ku, Osaka-shi Inside the Molding & Giken Co., Ltd. (72) Osamu Murakami 3-4-1-15 Takeshima, Nishiyodogawa-ku, Osaka-shi F-term in Fukuda Seiko Co., Ltd. (reference) 5G333 AA09 AA13 AB03 AB22 AB27 BA01 CB17 CC11 DA03 DA14 EA01

Claims (2)

[Claims] 1. A semi-molten elastomer or an olefin-based synthetic resin extruded from a die of an extrusion molding machine is sequentially fed into a plurality of molding dies arranged at predetermined intervals in a water tank, An electric wire formed into a roll shape by narrowing down to a cylindrical shape with a part of the periphery overlapping and gradually cooling and solidifying in this state to cool the inner and outer peripheral surfaces of the synthetic resin with a temperature difference. A method for manufacturing an electric wire protection member, wherein a winding habit is generated in the protection member due to internal residual stress. 2. An apparatus which is disposed between an extruder and a take-off machine and continuously manufactures a roll-shaped electric wire protection member with a synthetic resin extruded from the extruder. And a plurality of forming dies attached to the side walls and the partition walls of the water tank, and each of the forming dies is provided with a spiral opening. An apparatus for manufacturing a wire protection member, characterized in that the opening is set so that its diameter gradually decreases from the one located on the side of the extruder to the one located on the side of the take-off machine.