JPH05137225A - Cable duct - Google Patents

Abstract

PURPOSE:To enhance workability, heat resistance and electromagnetic shielding effect without causing cost increase. CONSTITUTION:Since a duct body 4 is composed of an insulating material such as plastic or FRP, the duct body can be formed into various shapes with high workability at low cost. Heat resistant effect can also be enhanced because a metallic film 5 is formed through low temperature spraying onto the inner face of the insulating duct body 4. Furthermore, weight of cable duct 2 can be reduced by making thin the metallic film 5. Electromagnetic noise can also be shielded by the metallic film 5 formed on the inner face of the duct body 4. When the metallic film 5 is connected with an earth line, electromagnetic shielding effect and leakage current preventing effect can be enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention forms a metal film by low temperature spraying on the surface and / or the inner surface of a cylindrical duct body for accommodating a communication cable or the like, which requires consideration for adverse effects such as electromagnetic noise. Regarding cable ducts.

[0002]

2. Description of the Related Art When a communication cable, which is a basic component of a wired transmission line, is installed outdoors, it is not only affected by the natural world such as wind and rain, earthquakes, temperature changes, but also due to electromagnetic noise, external work, vehicles, etc. Are also easily affected.

Therefore, the communication cable equipment is required to have not only the stability of the cable transmission quality but also the high reliability of the equipment as a whole, and at the same time, the construction and maintenance can be easily and economically performed. On the other hand, when it is installed in a factory or a building, it is necessary to consider the adverse effects of electromagnetic noise and fire accidents due to leakage current.

FIG. 4 shows an example of a facility condition of a cable duct in floor duct construction, in which a concrete duct 1 constituting a floor is embedded with a metallic duct 2. A plurality of communication cables 3 and 3 are housed in the duct 2. The burying work of the communication cable 3 with the metal duct 2 is mainly used for the low-voltage indoor work of a portion for accommodating a large number of communication cables 3 in a factory or a substation of a building. ..

[0005]

By the way, not only the above-mentioned conventional duct 2 made of metal, but the cable rack and the like are made of various materials such as steel, plastic, and FRP in addition to metal. There is.

Steel is relatively strong and has an electromagnetic shielding effect, but on the other hand, it is heavy and easily rusted, and therefore requires surface treatment for rust prevention, which is disadvantageous in terms of cost. The plastic and FRP products have good workability, but have not only poor heat resistance but also a drawback that they have no electromagnetic shielding effect.

As described above, since the duct 2 made of each material has advantages and disadvantages, the duct 2 made of a material satisfying appropriate conditions is adopted according to the state of the location where the duct 2 is disposed.

However, recently, the reliability of communication information due to the influence of noise due to electromagnetic waves has been particularly emphasized, and in order to solve these problems, there was no choice but to rely on the steel product.

The present invention has been made in view of such circumstances, and provides a cable duct capable of improving workability, heat resistance, and electromagnetic shielding effect without increasing cost. With the goal.

[0010]

In order to achieve the above object, the cable duct of the present invention has a metal film formed on the surface and / or the inner surface of an insulative tubular duct body for accommodating a cable by low temperature spraying. It is characterized by being formed.

[0011]

In the cable duct of the present invention, since the tubular duct body is made of an insulating material such as plastic or FRP, the duct body is low in cost, has good workability, and is suitable for various shapes. Can be formed. Further, since the metal film is formed on the surface and / or the inner surface of the insulative tubular duct body by low temperature spraying, the heat resistance effect can be enhanced.

Further, since the thickness of the metal film can be changed appropriately, the weight of the duct can be reduced when the thickness is reduced. Furthermore, the surface of the tubular duct body and / or
Alternatively, since the metal film is formed on the inner surface, noise of electromagnetic waves can be shielded. Further, by connecting the earth line to the metal film formed on the surface and / or the inner surface of the tubular duct body, the electromagnetic shielding effect and the leakage preventing effect can be enhanced.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawings described below, the same parts as those in FIG. 4 will be assigned the same reference numerals and overlapping explanations will be omitted. FIG. 1 shows an embodiment of the cable duct of the present invention, in which the duct body 4 of the cable duct 2 is formed in a tubular shape. The material of the duct body 4 is made of an insulating material such as plastic or FRP.
A metal film 5 is formed on the inner surface of the duct body 4 by low temperature spraying.

The cable duct 2 having such a structure is formed as follows. First, plastic or FRP
Is used to form the duct body 4 having a predetermined shape. The duct body 4 is not limited to the closed type as shown in the figure, but may be a lid provided with a lid or the like. After the formation of the duct body 4, the metal film 5 is formed on the inner surface of the duct body 4 by low temperature spraying.

As described above, in this embodiment, since the duct body 4 is made of an insulating material such as plastic or FRP, it is not only low in cost but also has good workability and can be formed into various shapes. It is possible to form a combined duct body. Further, since the metal film 5 is formed on the inner surface of the insulative duct body 4 by low temperature spraying, the heat resistance effect can be enhanced. Further, since the thickness of the metal film 5 can be changed appropriately, the weight of the cable duct 2 can be reduced when the thickness is reduced.

Furthermore, a metal film 5 is formed on the inner surface of the duct body 4.
Since this is formed, the electromagnetic noise can be shielded. Further, by connecting the earth line to the metal film 5 formed on the inner surface of the duct body 4, the electromagnetic shielding effect and the leakage prevention effect can be enhanced.

FIG. 2 shows another embodiment in which the structure of the cable duct of FIG. 1 is changed. In the drawings described below, the same parts as those in FIG. 1 are designated by the same reference numerals, and overlapping description will be omitted. A metal film 6 is formed on the surface of the duct body 4 of the cable duct 2 by low temperature spraying.

When the cable duct 2 having such a structure is formed, the duct body 4 having a predetermined shape is formed by using plastic or FRP as described above. After the formation of the duct body 4, the metal film 6 is formed on the surface of the duct body 4 by low temperature spraying.

As described above, in this embodiment, the duct body 4 is made of an insulating material such as plastic or FRP, and the metal film 6 is formed on the surface by low temperature spraying. Moreover, not only is the cost low, but the workability is good and the heat resistance effect can be enhanced. Furthermore, the weight of the cable duct 2 can be reduced, the noise of electromagnetic waves can be shielded, and the electromagnetic shielding effect and the leakage prevention effect can be enhanced.

FIG. 3 shows still another embodiment in which the structure of the cable duct of FIGS. 1 and 2 is changed. The inner surface and the surface of the duct body 4 of the cable duct 2 are made of metal by low temperature spraying. The film 6 is formed. When the cable duct 2 having such a structure is formed, the duct body 4 having a predetermined shape is formed by using plastic or FRP as described above.
To form. After the formation of the duct body 4, the metal film 6 is formed on the inner surface and the surface of the duct body 4 by low temperature spraying.

As described above, in this embodiment, since the duct body 4 is made of an insulating material such as plastic or FRP, the cost is not increased. Furthermore, since the metal film 6 is formed on the inner surface and the surface by low temperature spraying, the workability is good, the heat resistance effect can be enhanced, the weight of the cable duct 2 can be reduced, and the noise of electromagnetic waves can be reduced. Can be more reliably shielded, and the electromagnetic shielding effect, the leakage prevention effect, etc. can be enhanced more reliably.

In each of the above embodiments, the case where the present invention is applied to the cable duct has been described.
The present invention is not limited to this example, and may be applied to those related to those that accommodate cables, such as cable racks.

[0023]

As described above, according to the cable duct of the present invention, since the tubular duct body is made of an insulating material such as plastic or FRP, the cost is low and processing is possible. It is possible to form a duct body that has various properties and is suitable for various shapes. Further, since the metal film is formed on the surface and / or the inner surface of the insulative tubular duct body by low temperature spraying, the heat resistance effect can be enhanced.
Further, since the thickness of the metal film can be changed appropriately, the weight of the duct can be reduced when the thickness is reduced. Furthermore, since the metal film is formed on the surface and / or the inner surface of the tubular duct body, it is possible to shield the noise of electromagnetic waves. Further, by connecting the earth line to the metal film formed on the surface and / or the inner surface of the tubular duct body, the electromagnetic shielding effect and the leakage preventing effect can be enhanced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a cable duct of the present invention.

FIG. 2 is a perspective view showing another embodiment in which the configuration of the cable duct of FIG. 1 is changed.

FIG. 3 is a perspective view showing still another embodiment when the configuration of the cable duct of FIGS. 1 and 2 is changed.

FIG. 4 is a perspective view showing a conventional cable duct.

[Explanation of symbols]

 2 Cable duct 4 Duct body 5, 6 Metal film

Claims (1)

[Claims] 1. A cable duct, characterized in that a metal film is formed on the surface and / or the inner surface of an insulative tubular duct body for accommodating a cable by low temperature spraying.