JPH0449781Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an electromagnetic shielding cable with excellent shielding properties.

[Prior Art] Generally, grain-oriented silicon steel has very high magnetic permeability and low iron loss, and is therefore used for iron cores of transformers, motors, and the like. Applicants also believe that when this grain-oriented silicon steel is used as the magnetic layer of an electromagnetic cable, the above advantages will be taken advantage of, and it will be extremely flexible in the low induced voltage region of 10V/Km to 100V/Km. It has been discovered that this can be used as an electromagnetic shielding cable with excellent characteristics.

[Problems to be Solved by the Invention] However, this grain-oriented silicon steel has the drawbacks of being mechanically brittle and unstable in longitudinal elongation due to its material properties. For this reason, it can be wound into relatively large-diameter coils such as iron cores of transformers and motors, but when used as the magnetic layer of electromagnetic cables, it can be wound on small-diameter conductive layers with an outer diameter of about 15 to 40 mm. Due to the above-mentioned drawbacks, cracking occurs at the edge of the grain-oriented silicon steel sheet in the process of continuously wrapping the grain while applying tension, and during this process, the tape of the grain-oriented silicon steel sheet frequently breaks. do,
There was a problem in that it was not possible to stably manufacture electromagnetic cables.

Additionally, grain-oriented silicon steel sheets are coated with an inorganic insulating coating for corrosion prevention purposes, but when wrapped around a small-diameter conductive layer as the magnetic layer of an electromagnetic cable, this coating peels off. There was also the problem that the grain-oriented silicon steel plates would rust, making them useless as corrosion protection.

[Means for Solving the Problems] The present invention has been made to solve the above problems, and is an electromagnetic cable consisting of a cable core, a conductive layer, a magnetic layer, and a sheath. An electromagnetic shielding cable, wherein the magnetic layer is a laminated silicon steel strip formed by bonding a plastic film to a grain-oriented silicon steel plate, which is wound on the conductive layer. I will provide a.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view of an electromagnetic shielding cable according to the present invention, in which 1 is a cable core, 2 is a conductive layer, 3 is a magnetic layer, and 4 is a sheath. As a cable core, insulated wires made of annealed copper wire covered with plastic such as polyethylene or foamed polyethylene are twisted in pairs or twisted in pairs, and these twisted twisted wires or twisted insulated wires are assembled into a predetermined logarithm.
Alternatively, twisted pairs or twisted wires are twisted into units with a predetermined logarithm, and then these units are twisted together to make a predetermined logarithm, which is then pressed and wrapped with tape made of plastic, rubber, cotton, paper, etc. is used. As the conductive layer, a corrugated aluminum sheath is generally used, but other materials such as a smooth aluminum sheath, horizontally wound copper or aluminum tape, and aluminum laminate tape may also be used. As a sheath,
Plastics such as polyethylene or vinyl are used.

FIG. 2 is a cross-sectional view of the laminated silicon steel strip 30 used as the magnetic layer 3 in FIG. A polyethylene film 32 with a thickness of 0.05 mm is attached to one side of the cable, and when used as a magnetic layer of a cable, the width is 20 mm to 45 mm.

In the case of the laminated silicon steel strip 30 as shown in FIG. 2, since the polyethylene film 32 is bonded to the grain-oriented silicon steel plate 31, the laminated silicon steel strip winding process during the manufacture of the electromagnetic cable , no cracks occur at the edges of the grain-oriented silicon steel sheet 31, and therefore the laminated silicon steel strip 30
The tape does not break, making it possible to manufacture stable electromagnetic shielding cables. Further, even if a crack should occur at the edge portion of the grain-oriented silicon steel plate 31, the polyethylene film 32 effectively prevents the crack from progressing, so that tape breakage will not occur. Furthermore, during cable installation, even if a crack should occur at the edge of the grain-oriented silicon steel plate 31, the tape will not break due to the effect of the polyethylene film 32, as in the cable manufacturing process. Note that it is effective to wrap the laminated silicon steel strip around the cable so that the polyethylene film surface faces the outside of the cable.

FIG. 3 is a sectional view of another embodiment of the laminated silicon steel strip, which is made by adhering polyethylene films 32 with a thickness of 0.05 mm to both surfaces of a grain-oriented silicon steel plate 31. In this case, cracking of the grain-oriented silicon steel plate 21 can be more reliably prevented, and peeling off of the insulating coating 33 can also be completely prevented.

As shown in the examples, the plastic film used was a polyethylene film with a thickness of 0.05 mm.
Aluminum laminate tape made using the polyethylene film is used in communication cables.
LAP sheath etc. are widely used, so the price,
Although preferred in terms of manufacturing, the present invention is not limited to this, and may be a plastic film such as polyester or vinyl, or a multilayer film combining these, and the thickness can be changed as appropriate. be.

In addition, by bonding a polyethylene film wider than the grain-oriented silicon steel plate to both sides of the grain-oriented silicon steel plate, and bonding the polyethylene films that protrude from the edges of the grain-oriented silicon steel plate,
The structure may be such that the grain-oriented silicon steel plate is completely wrapped in a polyethylene film.

[Effects] In the electromagnetic shielding cable of the present invention, since the magnetic layer is a laminated silicon steel strip made by bonding a plastic film to a grain-oriented silicon steel sheet, It is extremely useful because it overcomes the disadvantages of mechanical brittleness and unstable elongation, and prevents cracking of grain-oriented silicon steel sheets during cable manufacturing and installation. It is also effective in preventing the insulating film coated on grain-oriented silicon steel sheets from peeling off.
It can prevent rust on grain-oriented silicon steel sheets.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of an electromagnetic shielding cable according to the present invention, Figure 2 is a cross-sectional view of a laminated silicon steel plate with a polyethylene film adhered to one side used as the magnetic layer in Figure 1, and Figure 3 is a cross-sectional view of the electromagnetic shielding cable according to the present invention. FIG. 6 shows a cross-sectional view of a laminated silicon steel plate with polyethylene films adhered to both sides in another embodiment of the magnetic layer. DESCRIPTION OF SYMBOLS 1... Cable core, 2... Conductive layer, 3... Magnetic layer, 4... Sheath, 30... Laminated silicon steel strip, 31... Grain-oriented silicon steel plate, 32... Polyethylene film, 33... Insulating coating.

Claims (1)

[Claims for Utility Model Registration] 1. An electromagnetic cable comprising a cable core, a conductive layer, a magnetic layer, and a sheath, wherein the magnetic layer is formed by being wound on the conductive layer. Furthermore, an electromagnetic shielding cable is characterized in that it is a laminated silicon steel strip made by adhering a plastic film to a grain-oriented silicon steel plate. 2. The electromagnetic shielding cable according to claim 1, wherein the magnetic layer is a laminated silicon steel strip made by adhering plastic films to both sides of a grain-oriented silicon steel plate. 3. Claims 1 or 3, wherein the magnetic layer is a laminated silicon steel strip made by adhering a plastic film to a grain-oriented silicon steel plate coated with an insulating film. Electromagnetic shielding cable described in Section 2.