CN101447249A

CN101447249A - Cable screening wire

Info

Publication number: CN101447249A
Application number: CNA2008102432606A
Authority: CN
Inventors: 颜君
Original assignee: CHANGSHU HL ELECTRIC WIRE CABLE Co Ltd
Current assignee: CHANGSHU HL ELECTRIC WIRE CABLE Co Ltd
Priority date: 2008-12-19
Filing date: 2008-12-19
Publication date: 2009-06-03

Abstract

The invention relates to a cable screening wire and belongs to the technical field of electric wires and cables. The cable screening wire comprises a center conductor, at least an insulating layer extruded outside the center conductor and a screening layer positioned outside the insulating layer. The screening layer is a metal coating layer directly combined outside the insulating layer. The invention has the advantages that the whole screening layer can be caused to be smooth to avoid characteristic impedance to change, thereby reducing the attenuation and the loop loss; and because metal wire braided bands, metal filament bands, metal foil bands or copper tubes in the prior art are replaced by the metal coating layer, materials can be effectively saved, the weight is lightened, and the dimension is reduced.

Description

Cable screening wire

Technical field

The invention belongs to technical field of electric wires and cables, be specifically related to a kind of cable screening wire.

Background technology

Cable in use, come from the interference of cable outside for phase mutual interference between the loop of reducing cable self and minimizing, therefore also needing to take shielding measure, so-called shielding measure is to utilize the metallic shield body that main string loop and interfered loop are separated and use a kind of measure that the electromagnetic field that makes interference weakens.

Shielding measure in the prior art or title shield technology mainly contain following four kinds: the one, and braid shielded; The 2nd, twine shielding; The 3rd, the metal compound belt shielding; The 4th, the copper pipe shielding.

Figure 1 shows that also be above mentioned a kind of cable screening wire in the prior art, comprise center conductor 1, squeeze and protect the insulating barrier 2 outside center conductor 1 and be located at screen 3 outside the insulating barrier 2 that screen 3 is the mask tape by metal wire knitted.

Figure 2 shows that the another kind of cable screening wire in the prior art, comprise center conductor 1, squeeze and to protect the insulating barrier 2 outside center conductor 1 and to be located at screen 3 outside the insulating barrier 2 that different with Fig. 1 structure is that wire belt is wrapped in outside the insulating barrier 2 as shield.

Figure 3 shows that the also a kind of cable screening wire in the prior art, comprise center conductor 1, squeeze and to protect the insulating barrier 2 outside center conductor 1 and to be located at screen 3 outside the insulating barrier 2 that different with Fig. 1 structure is that the metal forming band is coated on outside the insulating barrier 2.

Figure 4 shows that another cable screening wire in the prior art, comprise center conductor 1, squeeze and to protect the insulating barrier 2 outside center conductor 1 and to be located at screen 3 outside the insulating barrier 2 that different with Fig. 1 structure is that copper pipe is nested with outside insulating barrier 2 as screen 3.

The existing shortcoming of structure shown in Figure 1 of such scheme is: because whole screen 3 adopts is metal wire knitted mask tape and to make it to be positioned at insulating barrier 2 with mechanical force outer, therefore have the gap between screen 3 and the insulation conducting shell 2, no matter the consummate extremely how degree of processing technology, all can't eliminate gap between the two, and can't eliminate the suddenly big or suddenly small problem in gap between screen 3 and the insulating barrier 2, thereby influence shield effectiveness, especially in the process of signal transmission, can cause the reflection and the decay of signal, reduce the ability of cable transmission signal.

Above-mentioned drawback by structure shown in Figure 2 is: because whole screen 3 adopts is that wire belt is wrapped or claims and twines, therefore inner surface and all utmost point out-of-flatnesses of outer surface of screen 3, and out-of-flatness is the inducement that causes decay and signal reflex, particularly when high-frequency, decay and reflection often show fairly obvious.

Above-mentioned deficiency by structure shown in Figure 3 is: owing to adopt the situation of this structure separately is not too many, usually back its certain effect of competence exertion need match with Fig. 1 or structure shown in Figure 2, even therefore use separately when still using, can expose the existing described deficiency of Fig. 1 or Fig. 2 structure equally with Fig. 1 or with Fig. 2 combination (collocation).

Above-mentioned shortcoming by structure shown in Figure 4 is: although as the copper pipe surfaces externally and internally of screen 3 smooth and when the high frequency surface to decay and reflection be better than aforesaid three kinds of structures, but owing to can have the gap between copper pipe and the insulating barrier 2, and copper pipe is comparatively hard, is difficult to behind cable molding even at all can't be crooked.

Above-mentioned four kinds of structures also exist a common weakness, and that is exactly that materials used is many, weight and volume is big.

Summary of the invention

Task of the present invention be to provide outer surface that combining between a kind of screen and the insulating barrier do not exist gapped and screen also for smooth, can reduce effectively characteristic impedance change use embody reduce decay and reflection and help the cable screening wire saving polymeric barrier layer materials and alleviate whole cable weight and volume.

Task of the present invention is finished like this, a kind of cable screening wire, and it comprises center conductor, squeeze and to protect at least one layer insulating center conductor outside and to be positioned at screen insulating barrier outside, described screen is directly to be combined in the described insulating barrier coat of metal outward.

The coat of metal of the present invention is copper plate, nickel coating, tin coating or aluminium coated or titanizing layer.

The coat of metal of the present invention is a copper plate.

The technical scheme that the present invention recommended is owing to using the direct plating of the coat of metal outward instead outside insulating barrier with being arranged at insulating barrier with metal wire knitted band, wire belt, metallic foil or copper pipe as screen in the prior art, therefore can make whole screen show as very bright and clean and avoid characteristic impedance to change, thereby can reduce decay and loop loss; Owing to adopt the coat of metal to substitute metal wire knitted band, wire belt, metallic foil or the copper pipe of prior art, thus economical with materials, weight reduction and minification effectively.

Description of drawings

Fig. 1 is the structure chart of a kind of cable screening wire in the prior art.

Fig. 2 is the structure chart of the another kind of cable screening wire in the prior art.

Fig. 3 is the structure chart of the also a kind of cable screening wire in the prior art.

Fig. 4 is the structure chart of another cable screening wire in the prior art.

Fig. 5 is the first example structure figure of cable screening wire of the present invention.

Fig. 6 is the second example structure figure of cable screening wire of the present invention.

Fig. 7 is the 3rd example structure figure of cable screening wire of the present invention.

Embodiment

Embodiment 1:

Ask for an interview Fig. 5, a kind of cable screening wire comprises center conductor 1, squeezes outside center conductor 1 and is covered with insulating barrier 2, and plating has been useful on the screen 3 of shielding action outside insulating barrier 2.In the present embodiment, directly being formed in is the copper plate that is of the screen 3 of direct plating outside insulating barrier 2, but does not repel nickel coating, tin coating or aluminium coated and even titanizing layer.With any surface finish that copper plate can make screen 3 combine with insulating barrier 2 as screen 3, both embody zero-gap bond, thereby can improve the characteristic impedance of shielding conductor significantly, and the loss of decay and loop is effectively suppressed.In addition, if add oversheath outside screen 3, because screen 3 be copper plate, outer surface is also very bright and clean, thus can with the oversheath zero-gap bond.

Embodiment 2:

Ask for an interview Fig. 6, insulating barrier 2 has two-layer, and promptly insulating barrier 2 shows as the composite insulation layer structure, and screen 3 is copper plate and directly is plated on the layer insulating 2 that is positioned at the outside.When can playing and use, this structure avoids undermining the effect of center conductor 1 during wire stripping.According to the description of present embodiment, can know that fully insulating barrier 2 can also be 3 layers or more multi-layered, therefore should not limit technical solution of the present invention by the number of the concrete number of plies of insulating barrier 2, all the other are all with the description to embodiment 1.

Embodiment 3:

Ask for an interview Fig. 7, though provided quantity and be three but obviously be not subjected to a group switching centre conductor 1 of concrete restriction, each center conductor 1 outer squeezing is covered with insulating barrier 2, and jointly squeezed and covered squeezing the outside be overlying on each insulating barrier 2 outside the center conductor 1 separately by the insulating barrier 2 of the second layer, screen 3 direct plating that is to say that the insulating barrier 2 by the second layer squeezes insulating barrier 2 containings that are overlying on outside the center conductor 1 with all outside the insulating barrier 2 of this second layer.All the other are all with the description to embodiment 1.

The material of the screen 3 that exemplifies except the problems referred to above, if with copper aluminium composite bed or copper tin composite bed as screen 3, also be fine fully so.

Claims

1, a kind of cable screening wire, it comprises center conductor (1), squeeze and to protect at least one layer insulating (2) center conductor (1) outside and to be positioned at screen (3) outside the insulating barrier (2), it is characterized in that described screen (3) is directly to be combined in described insulating barrier (2) coat of metal outward.

2, cable screening wire according to claim 1 is characterized in that the described coat of metal is copper plate, nickel coating, tin coating or aluminium coated or titanizing layer.

3, cable screening wire according to claim 2 is characterized in that the described coat of metal is a copper plate.