JP2006173044A - Metal shield wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal shield wire, of which a shielding property is not deteriorated even if a gap is generated at an overlapped part of metal tapes constructing a metallic shield layer by bending, capable of maintaining a stable shielding property. <P>SOLUTION: The shield wire is at least composed of a shielded core wire 1, metallic shield layers 7 made of metallic tape 5 divided into four, covering the core wire so as to be attached in longitudinal direction, and an external cover for protection 6 covering the outer periphery of the metallic shield layers 7. The metallic shield layers 7 are formed into a plurality of inside layer and outside layer. An overlapping part 5a of adjacent two layers of a metal tape 5, namely, that of inside metallic shield layer 8 and outside metallic shield layer 9 are arranged so as to shift by 45 degree in radial direction so that the inside metallic shield layer 8 and the outside metallic shield layer 9 are not overlapped mutually. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a metal shielded wire (shielded wire) (cable with a shield function) provided on a wiring material in order to prevent external electromagnetic noise from being mixed into the electrical circuit of an electronic device from the wiring material. Including).

  Conventionally, as shown in FIG. 6, as this type of metal-shielded electric wire, at least one insulating wire core 1 in which an insulator 3 such as rubber or plastic is coated on a conductor 2, and a plurality of outer peripheral wires are provided on the outer periphery thereof. There has been proposed one comprising a metal shielding layer 4 in which a divided metal tape 5 such as a copper tape is longitudinally coated along the longitudinal direction of the insulating core 1 and a protective sheath 6 coated on the outer periphery thereof. (See Patent Document 1).

JP 2000-90748 A

  However, when a conventional metal shielded wire is bent at the time of manufacture or wiring to electrical equipment, etc., and the metal tape constituting the metal shield layer is wrinkled or slipped, there is a gap between the metal tape joints. There is a problem that the shielding performance of the metal shielding layer is lowered.

  The present invention solves the above problems, and even if the metal shielding wire is bent and a gap is formed in the joint of the metal tape constituting the metal shielding layer, the metal shielding layer does not deteriorate the shielding performance and has a stable shielding performance. An object of the present invention is to provide a metal shielded electric wire that can be maintained.

  According to a first aspect of the present invention, there is provided a metal shielded electric wire comprising at least one insulated wire core, a metal shield layer vertically coated with a plurality of metal tapes on the outer periphery thereof, and an outer periphery thereof covered with the metal shield layer. The metal shielding layer is formed in a plurality of inner and outer layers so that the joints of the metal tapes in the two adjacent inner and outer metal shielding layers do not overlap each other between the inner and outer layers. It is characterized by being displaced in the circumferential direction.

  According to the metal shielded electric wire of the present invention, the metal shield layer is formed in a plurality of inner and outer layers, and the metal tape joints in the two adjacent inner and outer metal shield layers are displaced in the circumferential direction so as not to overlap each other between the inner and outer two layers. As a result, the metal shielded wire is bent at a predetermined angle during its manufacture or when it is routed to electrical equipment, etc., and the metal tape constituting the metal shield layer is wrinkled and slipped. Of the two metal shielding layers, for example, when a gap is formed at the joint of the metal tape of the inner metal shielding layer, the joint is closed with the metal tape of the outer metal shielding layer. Further, when a gap is formed at the joint of the metal tape of the outer metal shielding layer, the joint is closed by the metal tape of the inner metal shielding layer. Therefore, even if there is a gap at the joint of the metal tape of the metal shielding layer, there is substantially no gap, and the direct current resistance of the metal shielding layer is reduced by forming the metal shielding layer in multiple layers inside and outside. Therefore, even in a state where the metal shielded electric wire is bent, the shielding performance of the metal shielding layer is not lowered, and the stable shielding performance can be maintained.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of a metal shielded electric wire according to the present invention, and FIG. 2 is an enlarged sectional view thereof. In addition, the same code | symbol is attached | subjected to the thing of the same structure as the conventional metal shielding wire. This metal shielded wire includes one (this example) or a plurality of insulated wire cores (cable cores) 1, a metal shielding layer (shield layer) 7 coated on the outer periphery thereof, and a polyvinyl chloride resin on the outer periphery thereof. Is provided with a protective sheath (sheath) 6 which is extrusion-coated.

  The insulated wire core 1 is formed by covering a conductor 2 with an insulator 3 such as rubber or plastic. The metal shielding layer 7 is formed in a plurality of inner and outer layers (in this example, two layers). Two adjacent inner and outer layers, that is, the inner metal shielding layer 8 and the outer metal shielding layer 9 are each a metal tape 5 (metal foil, metal film) such as a copper tape divided into a plurality of sheets (four in this example). Are disposed at a predetermined angle, for example, 45 degrees as shown in the figure so that the seams 5a along the longitudinal direction do not overlap each other between the inner and outer two layers. In this manner, the outer periphery of the insulating wire core 1 is formed with a longitudinal coating along the longitudinal direction.

  When the inner metal shielding layer 8 constituting the metal shielding layer 7 is formed, for example, as shown in FIGS. 3 and 4, on the front side portion (downstream of the traveling line) of the insulating core 1 on the traveling line. A pair of tape winding bodies 10 such as a reel and a bobbin around which a predetermined length of the metal tape 5 is wound and stored are arranged facing each other in the vertical direction. In addition, another pair of tape winding bodies 10 are arranged opposite to each other in the left-right direction at a rear side portion (upstream side of the travel line) spaced a predetermined distance in the longitudinal direction of the insulated wire core 1. Next, the insulated wire core 1 is passed between the two pairs of loop wound bodies 10, and the two-to-four loop wound bodies 10 are moved to the arrows while running at a predetermined speed in the direction of the arrow in FIG. The metal tape 5 is fed out from each loop wound body 10 so that both side edges of each metal tape 5 abut each other without gaps on the outer periphery of the insulated wire core 1 along the longitudinal direction. It is formed by coating.

  Next, in the case of forming the outer metal shielding layer 9 constituting the metal shielding layer 7, although not shown in the drawing, the insulating core 1 covered with the inner metal shielding layer 8 is either left or right in the circumferential direction. Direction, for example, by rotating 45 degrees, passing again between the two pairs of tape windings 10, and in the same manner as forming the inner metal shielding layer 8, on the outer periphery of the insulated wire core 1, The both side edges of each metal tape 5 face each other with no gap through the inner metal shielding layer 8, and the joint 5 a of the metal tape 5 is the joint 5 a of the metal tape 5 in the inner metal shielding layer 8. It is formed by covering vertically along the longitudinal direction so as not to overlap each other between the inner and outer two layers.

  In this example, the seam 5a of the metal tape in the outer metal shielding layer 9 is displaced 45 degrees in the circumferential direction with respect to the seam 5a of the metal tape 5 in the inner metal shielding layer 8. Since the seam 5a of the metal tape 5 should not be overlapped between the inner and outer two layers 8, 9 of the shielding layer 7, it may be displaced less than 45 degrees or more in the circumferential direction. Further, in this example, the metal shielding layer 7 is formed using the metal tape 5 divided into four sheets, but the metal shielding layer 7 using the metal tape 5 divided into two, three, or five or more sheets. May be formed. The number of metal tapes 5 used is selected in consideration of the ease of forming the metal shielding layer 7 and the like. In general, the outer diameter of the insulated wire core 1 is small, and in the case of a thin object, the number of used sheets is small, the outer diameter of the insulated wire core 1 is large, and the number of used sheets increases as the thickness increases. FIG. 5 shows a metal shielding layer 7, that is, an inner metal shielding layer 8 and an outer metal shielding layer 9 formed by covering a metal tape 5 divided into six pieces along the outer periphery of a thick insulated wire core 1. It shows the state to do. Furthermore, the metal tape 5 may use not only a copper material but also a copper material and an iron material, nickel material, or the like having a high magnetic permeability. This is preferable because the shielding performance in a wider frequency band can be improved.

  In the metal shielded electric wire according to the present invention, as described above, the metal shield layer 7 is formed in a plurality of inner and outer layers, and the joint 5a of the metal tape 5 in the two adjacent metal shield layers 8 and 9 is the inner and outer two layers. Since the metal shielded electric wires are arranged so as not to overlap with each other in the circumferential direction, the metal shielded wire 7 is bent at a predetermined angle during its manufacture or when it is routed to electrical equipment, etc., thereby forming the metal shield layer 7. When wrinkles and slips occur in the metal tape 5 and there is a gap in the joint 5a of the metal tape 5 of the inner metal shielding layer 8, among the adjacent two inner and outer metal shielding layers 8, 9, for example, The joint 5a is closed with the metal tape 5 of the outer metal shielding layer 9. Further, when a gap is formed in the joint 5 a of the metal tape 5 of the outer metal shielding layer 9, the joint 5 a is closed with the metal tape 5 of the inner metal shielding layer 8. Accordingly, even if there is a gap in the joint 5a of the metal tape 5 between the inner and outer two layers of the metal shielding layer 7, that is, between the inner metal shielding layer 8 and the outer metal shielding layer 9, there is substantially no gap. In addition, since the direct current resistance of the metal shielding layer is lowered by forming the metal shielding layer 7 in the inner and outer layers, the shielding performance of the metal shielding layer 7 does not deteriorate even when the metal shielding wire is bent, and is stable. The shielding performance can be maintained.

It is a perspective view which shows one Embodiment of the metal shielding wire which concerns on this invention. It is sectional drawing of the metal shielding wire shown in FIG. FIG. 2 is a perspective view showing an example of a method for forming an inner metal shielding layer constituting the metal shielding layer in the metal shielding electric wire of FIG. 1. FIG. 4 is a diagram of the method for forming an inner metal shielding layer in FIG. 3 as viewed from the downstream side in the traveling direction of the insulated wire core toward the upstream side. In the forming method of FIG. 3, when the metal tape is coated along the outer periphery of the thick insulation core using six metal tapes, the insulation core is viewed from the downstream side to the upstream side in the running direction. It is a figure of a state. It is sectional drawing which shows the conventional metal shielding wire.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insulated wire core 2 Conductor 3 Insulator 5 Metal tape 5a Seam 6 Protective jacket 7 Metal shielding layer 8 Inner metal shielding layer 9 Outer metal shielding layer 10 Tape winding body

Claims (1)

  In a metal shielded electric wire comprising at least one insulated wire core, a metal shield layer vertically coated with a metal tape divided into a plurality of pieces on the outer periphery thereof, and a protective sheath coated on the outer periphery thereof, The metal shielding layer is formed in a plurality of inner and outer layers, and the seam of the metal tape in the two adjacent inner and outer metal shielding layers is displaced in the circumferential direction so as not to overlap each other between the inner and outer layers. Metal shielded wire.

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