JPH03214513A - Flat coaxial cable and multicore parallel type flat coaxial cable - Google Patents

Abstract

PURPOSE:To save a wiring space at the time of use by successively providing an insulating layer, a sealed layer and an outer coating layer on the periphery of a central conductor for forming a coaxial wire in a circular shape in its outline followed by pressure processing for flattening. CONSTITUTION:After an insulated layer 2, a sealed layer 3 and an outer coating layer 4 are successively provided on the periphery of a central conductor 1 to form a coaxial wire in the circular shape in its outline, this is given pressure processing at a normal temperature or under a heated atmosphere for being flattened. Since in this way a flat coaxial cable 8 is flattened by pressure processing of the coaxial cable 7 in the circular shape in its outline so that an outer diameter (minor diameter) is reduced as compared with that the coaxial wire 7 in the circular shape in its outline so that a wiring space can be sharply saved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a coaxial cable used for internal wiring of electronic devices or connections between devices. More specifically, it concerns coaxial cables that are suitable for locations where wiring space is extremely limited. [Prior art] Signal transmission wires used for internal wiring of electronic devices include discrete insulated wires, coaxial cables,
Twisted cables and round multicore cables are known, but coaxial cables with a circular outer shape as shown in Figure 4 were mainly used due to their characteristics. Additionally, flat cables were used to reduce wiring space. [Problem to be solved by the invention] Even when wiring space is limited and the wiring space is reduced as much as possible or wired through a thin gap, relatively high frequency signals are used in electronic devices these days. Because of this, the flat cables that have been used in the past have been problematic due to their unsuitable transmission characteristics. Furthermore, while coaxial cables with a circular outer shape have excellent transmission characteristics, they have the disadvantage of increasing the outer diameter of the wire itself. When trying to make a coaxial cable thinner by reducing its outer diameter, the center conductor also had to be made thinner, which led to problems such as a reduction in physical strength and poor termination processability. The present invention has been made to solve the above problems, and aims to provide a coaxial cable that has excellent signal transmission characteristics, reduces wiring space, and can be wired even in thin gaps. [Means for Solving the Problems] In order to achieve the above object, the present invention provides (1) an insulating layer 2, a shield layer 3, and an outer covering layer 4 on the outer periphery of the central conductor 1;
A flat coaxial cable 8, characterized in that a coaxial line 7 having a circular outer shape is formed by successively forming a coaxial line 7 having a circular outer shape, and then being flattened by pressure treatment at room temperature or in a heated atmosphere. The coaxial wire 7 is placed between two plastic films S and 5', and the circular coaxial wire 7 is flattened by pressure treatment at room temperature or in a heated atmosphere.
A flat coaxial cable 9, characterized in that it is fixedly integrated with the two plastic films 5 and 5', and (3
) A plurality of coaxial wires 7 having a circular outer shape are arranged in parallel at regular intervals between two plastic films 5 and 5';
A multi-core parallel type characterized in that the plurality of circular coaxial wires 7 are flattened by pressure treatment at room temperature or in a heated atmosphere, and are fixedly integrated with the two plastic films 5, 5'. Located in flat coaxial cable lO. As the center conductor 1, a thin metal wire or a single or stranded wire of this plated wire is used. As the insulating layer 2, polyethylene, fluororesin, or foamed or porous materials thereof are used. As the shielding layer 3, a layer of wound metal tape, a horizontally wound layer of thin metal wires tightly wound laterally, or a braided metal layer of braided thin metal wires is used. As the outer coating layer 4 provided on the outer periphery of the shield layer 3, an extruded layer made of various plastic materials and a wound layer made of various plastic tapes are used. [Function] The flat coaxial cable 8 of the present invention has a coaxial line 7 having a circular outer shape.
Because it is flattened by pressure treatment, the outer diameter (minor diameter) is smaller compared to the coaxial cable 7, which has a circular outer diameter, making it possible to significantly save wiring space. Further, the circular coaxial wire 7 is arranged between two plastic films 5 and 5', and the circular coaxial wire 7 is subjected to pressure treatment.
The flat coaxial cable 9, which is made flat and integrated with two plastic films 5 and 5', has a structure in which the coaxial line is physically reinforced in addition to greatly reducing the wiring space. Further, a plurality of the circular coaxial wires 7 are arranged in parallel at regular intervals between two plastic films 5, 5', and are subjected to pressure treatment to flatten the plurality of circular coaxial wires 7, The multicore parallel flat coaxial cable 10, which is integrated with the two plastic films 5 and 5' to form a flat cable, can transmit a large amount of signals in a small space. [Example] Hereinafter, an example of the present invention will be explained using figures. Example 1 Example 1 will be explained using FIG. 4 and FIG. 1. A 7/0.08 m mild steel wire was used as the central conductor 1, and an insulating layer 2 made of porous polytetrafluoroethylene resin (PTFE, 70% porosity) was provided around the outer periphery to give an outer diameter of 1.5 m. 55 steel wires with a conductor diameter of 0.081 were horizontally wound to form a shield layer 3, and a polyester tape with a fusion layer (5.0 width x o.
was wound with 173 wraps to form an outer coating layer 4, and a coaxial wire 7 having a circular outer diameter and a finished outer diameter of 1.71φ and a characteristic impedance of 100Ω was manufactured (Fig. 4). Up to this point, the structure is the same as that of the conventional coaxial cable 7 having a circular outer diameter.Next, the circular coaxial cable 7 is passed between pressure rollers (pressure 10 kg/eII) at room temperature so that the long diameter is 2. 2
A flat coaxial cable 8 with a short diameter of 1.0 am was manufactured (Fig. 1). The characteristic impedance of this flat coaxial cable 8 was 70Ω. Example 2 Example 2 will be explained using FIG. 2. The process of manufacturing the coaxial wire 7 having a circular outer shape is the same as in Example 1, but next, the circular coaxial wire 7 is manufactured to a thickness of 0.5 mm. 2 sheets of PVC-polyester composite film 5, 1 m wide and 10 heel wide;
The circular coaxial wire 7 is flattened by passing it between rubber-lined heated rolls at a temperature of 130° C. (pressure 10 kg/ffl), and the two plastic films 5.5' and Integrate the major axis 2.
A flat coaxial cable 9 with a short diameter of 1.0 mm (excluding the tape protrusion) was manufactured. The characteristic impedance of this flat coaxial cable 9 was 60Ω. Example 3 Example 3 will be explained using FIG. 3. The process of manufacturing the coaxial wire 7 having a circular outer shape is the same as in Example 1, but next, three of the circular coaxial wires 7 are made to have a thickness of 0.1 mm and a width of 3 mm.
0 sheets of PVC-polyester composite film 5,5
' are placed in parallel at intervals of five cabinets, and the temperature is 130℃.
The three circular coaxial wires 7 were flattened using heat press (pressure 10 kg/j) and integrated with the two plastic films to produce a multicore parallel flat coaxial cable 10. This multicore parallel flat coaxial cable I
The characteristic impedance of O was 60Ω. [Effects of the Invention] The flat coaxial cable of the present invention makes it possible to significantly save wiring space during use, and also enables wiring in locations where there is no other way than to route the cable through an extremely thin gap. More specifically, it is effective for wiring cables inside various devices where wiring space is limited, signal cables for undercarpets, antenna cables routed between window frames and aluminum sashes, etc. In addition, the flat coaxial cable, which is placed between two plastic films and integrated with the film, has a structure in which the coaxial wire is physically reinforced, so that it can withstand severe friction during wiring. Become. Furthermore, by converting many flat coaxial cables into flat cables, it is possible to transmit many signals in a small amount of space8.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a flat coaxial cable according to a first embodiment of the present invention, Fig. 2 is a cross-sectional view of a flat coaxial cable according to a second embodiment of the present invention, and Fig. 3 is a multi-core parallel flat coaxial cable of the present invention. FIG. 4 is a cross-sectional view of the flat coaxial cable of the present invention before being flattened (also used as a cross-sectional view of a conventional coaxial cable with a circular outer shape). 1-center conductor, 2-insulating layer, 3-shielding layer, 4-covering layer, 5.5'-plastic film, 7-circular coaxial line (cable),

Claims (3)

[Claims] (1) After sequentially providing an insulating layer, a shield layer, and an outer covering layer on the outer periphery of the center conductor to form a circular coaxial line,
A flat coaxial cable characterized by being flattened by pressure treatment at room temperature or in a heated atmosphere. (2) The circular coaxial wire is placed between two plastic films and subjected to pressure treatment at room temperature or in a heated atmosphere to flatten the circular coaxial wire and fix it to the two plastic films. A flat coaxial cable characterized by being integrated. (3) A plurality of the circular coaxial wires are arranged in parallel at regular intervals between two plastic films, and the plurality of circular coaxial wires are flattened by pressure treatment at room temperature or in a heated atmosphere. and a multi-core parallel flat coaxial cable, characterized in that it is fixedly integrated with the two plastic films.