JPH0132646Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is applicable to electronic equipment, electrical equipment, cable lines,
The present invention also relates to a wire covering material for shielding electromagnetic waves generated from irregularly shaped parts used in between.

BACKGROUND ART In recent years, with the development of electronic devices such as computers, it has become a problem that electromagnetic waves generated by these electronic devices affect other devices, causing problems such as noise and malfunction. Therefore, the electric wires and cables that connect these devices to each other or within the devices are also required to be shielded to prevent interference due to electromagnetic waves.

In particular, the frequency bands of electromagnetic waves that are subject to shielding are
It ranges from 10KHz to 1000MHz. When electromagnetic waves in this range are incident on electronic devices, etc., they cause electromagnetic interference, causing malfunctions and noise. For this reason, a conductive layer is formed around the electric wire to reflect a portion of the electromagnetic waves to the outside and absorb the rest to provide a shielding effect. This shielding effect indicates the extent to which energy from the surface of an electromagnetic wave source can be attenuated, and the attenuation rate is expressed in decibels dB. This shielding effect SE is generally expressed by the following formula: SE = 20 x log (Ei/Et) Ei = electric field incident intensity Et = electric field transmission intensity As a guideline for this shielding effect, the attenuation rate is usually
It is said to be effective if it is 20 to 60 dB or higher.

Conventional technology In order to shield conventionally wired wires,
Electric wires were wrapped in tape-shaped metal foil, tape-shaped braided metal wires were wrapped around electrical wires, and cylindrical braided metal wires were wrapped around electrical wires.

Problems to be Solved by the Invention However, although braided metal wires have an excellent effect of shielding electromagnetic waves, they have the drawback of lacking flexibility. Therefore,
In the method of stacking and winding tape-like materials, it takes time and effort to stack and wind the wires, and when there is a connector or the like in the middle of the wire, it is difficult to wind this part. Moreover, in the case of a cover that covers a cylindrical object, it is not stretchable in the radial direction and it is not easy to draw the electric wire into the cover.

The present invention was devised in view of the above circumstances, and is flexible yet has appropriate rigidity, has appropriate elasticity in the radial direction, is easy to handle, and has an excellent shielding effect. The purpose of the present invention is to provide a wire covering material with a high temperature.

Means to Solve the Problems The present invention consists of winding a crimped synthetic fiber yarn that has been chemically plated with metal around the outer periphery of a synthetic monofilament yarn, which is then braided into a cylindrical shape. This is what happens.

The present invention will be explained below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes the wire covering material of the present invention, which has a structure in which threads 2 are braided into a cylindrical shape. As shown in FIG.
It is wound.

The monofilament yarn 3 is suitably a polyester monofilament yarn or a high-strength polyethylene monofilament yarn having high elasticity. These monofilament yarns 3 preferably have a Young's modulus of 1000 Kg/mm ² or more and a diameter of 0.1 to 0.4 mmφ.
If the diameter is less than 0.1 mmφ, the wire sheathing material 1 will be too flexible, and if the diameter is more than 0.4 mmφ, the rigidity will be too strong and the elasticity in the radial direction will be poor.

The crimped yarn 4 wound around the outer periphery of the monofilament yarn 3 is made of polyester yarn or polyamide yarn.
Use crimped multifilament yarn of 50 to 200 d. As the material, polyester yarn is preferred because of its excellent weather resistance.

The crimped yarn 4 may be wound in a single layer around the outer circumference of the monofilament yarn 3 in either a left-handed or right-handed manner, but in order to improve the shielding effect, the monofilament yarn 3
It is preferable to wind the wire in a left-handed or right-handed manner and then further wrap it around the outer circumference in the opposite direction to make it double or more.

The crimped yarn 4 is chemically plated. Copper or nickel is suitable as the metal for chemical plating. The amount of metal plated is suitably 10 to 50% of the weight of the crimped yarn 4. Ten
% or less, the shield effect becomes worse, and 50
% or more, the surface becomes hard and the texture becomes poor.

The chemical plating may be performed on the yarn 2 in which the crimped yarn 4 is wound around the monofilament yarn 3, or after the yarn 2 is braided into a cylindrical shape, A plating operation may be performed on the braided body. It is also possible to perform a plating operation on the crimped yarn 4 and then wind it around the monofilament yarn 3. In this case, even if the monofilament yarn 3 is not plated, the effect will hardly change.

Function In the present invention, an electric wire is inserted into the electric wire sheathing material 1 of the present invention, and is coated to shield electromagnetic waves. Even if there is a connector etc. in the middle of the electric wire, the electric wire covering material 1 in that part expands in the radial direction, so that the connector etc. can also be covered. The metal plated on the wire sheathing material 1 shields electromagnetic waves and prevents electromagnetic interference.

Effects of the invention According to the invention, it is extremely flexible compared to conventional braided metal wires, making it easier to insert electric wires, and also has appropriate rigidity and flexibility in the radial direction. Even if there is an irregularly shaped part such as a connector in the middle of the electric wire, it can be covered even with it.

Conventionally, electric wire binding materials made by braiding synthetic fiber monofilament yarn into a cylindrical shape have been used for the purpose of converging multiple electric wires, and by applying chemical plating to the monofilament yarn, a shielding effect can be imparted. is possible. However, monofilament yarn, which is a synthetic fiber, has a small surface area and an extremely smooth surface, so the amount of metal that adheres to it is not sufficient, and its adhesion to metal is poor, and the metal may peel off from the monofilament yarn during handling. , it is not possible to obtain an effective electromagnetic shielding effect.

In contrast, in the present invention, the crimped yarn is wound around the outer circumference of the monofilament yarn, and the crimped yarn is chemically plated, so that the surface area is large and the amount of metal adhesion is increased, and it is also easy to handle. The metal does not peel off during the process, and an effective shielding effect can be maintained for a long period of time.

Example A cylindrical braided body was formed by braiding the yarn 2, which is a polyester monofilament yarn 3 with a diameter of 0.1 mmφ, with a single winding of a 150 d polyester crimped yarn 4, into a 3 x 3 x 48 thread. The cylindrical braided body was chemically plated with copper to form the wire covering material 1 of the present invention. Therefore, the weight of this wire sheathing material 1 is 10.6
g/m, and the weight of this internally crimped yarn is 6.0
g/m, and the amount of copper deposited by plating is 1.8
g/m.

Next, a copper wire is drawn into the hard PVC pipe, which is treated as a coaxial cable, and is inserted into the sheathing material 1 of the above embodiment.This is then inserted into the absorption clamp 5 as shown in FIG. A high frequency current was passed through the copper wire between the signal generator 6 and the shield box 7, and the electromagnetic waves leaking from the coating material 1 were absorbed by the ferrite ring in the absorption clamp 5 and measured by the spectrum analyzer 8.

As a result, the attenuation rate of electromagnetic waves at 100MHz is
27dB and 35dB at 500MHz,
It had sufficient electromagnetic shielding effect.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the wire sheathing material of the present invention, and FIG. 2 is a plan view of the yarn constituting the wire sheathing material. FIG. 3 is a conceptual diagram of an apparatus for measuring the electromagnetic shielding effect of the wire coating material of the present invention. 1... Electric wire covering material, 2... Yarn, 3... Monofilament yarn, 4... Crimped yarn.

Claims (1)

[Scope of utility model registration request] An electric wire for electromagnetic shielding, characterized in that a yarn formed by winding a synthetic fiber crimped yarn chemically plated with metal around the outer circumference of a synthetic fiber monofilament yarn is braided into a cylindrical shape. Covering material.