JPH06325836A - Connecting structure for parallel strip line cable - Google Patents

Abstract

PURPOSE:To reduce a size and height in a connecting structure for a high frequency cable. CONSTITUTION:An insulating body 3 is arranged between a pair of parallel earth conductors 2, 2, while a notch part 5, by which a central conductor 4 is exposed along the extending direction of a parallel strip line cable 1, is formed in a terminal part 1a of the parallel strip line cable 1, in which the central conductor 4 is arranged in the inside of the insulating body 3. Hot lines 11, 22, 45 of members 10, 20, 44 to be connected are brought into contact with the central conductor 4 exposed by the notch part 5, so that the central conductor 4 and the hot line are connected with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency transmission line connection structure.

[0002]

2. Description of the Related Art Conventionally, as a line for transmitting a high frequency signal, generally, as shown in FIG. 8, a central conductor 50 is embedded in a cylindrical insulator 51 and an outer peripheral surface of the insulator 51 is grounded to a ground conductor 52. Coaxial cable 5 covered with
3 is used. Then, as a connector used for connecting such a coaxial cable 53, there is also a connector shown in FIG. The connector 60 includes a male connector 61 attached to the end of the coaxial cable 53 and a female connector 62 arranged on the circuit board 70. The male connector 61 is inserted into the female connector 62 and held. By doing so, the coaxial cable 53 is electrically connected to the circuit board 70.

[0003]

By the way, with the recent miniaturization of electronic devices, there is an increasing demand for miniaturization, particularly low profile, in the connection structure of the high-frequency transmission lines arranged in the gap inside the device. ing. However, in the conventional connection structure of the coaxial cable 53, the coaxial cable 53 is
There is a limit to thinning, that is, reducing the diameter (for example, a coaxial cable having a characteristic impedance of 50Ω has an outer diameter of 0.6 to 0.8).
mm), and since the connector 60 itself has a structure in which both male and female connectors 61 and 62 are connected as described above, there is a limit to downsizing, so it is difficult to downsize and reduce the height. there were.

In view of such a problem, the present invention further fills an insulating material between parallel strip line cables, that is, a pair of closely-arranged ground conductors, and the inside of the insulating material. This was done by focusing on the fact that it is easy to reduce the size and height when a high-frequency cable is constructed from one in which the center conductor is embedded. By reducing the size of such a parallel stripline cable connection structure, More compact cable structure,
The purpose is to reduce the height.

[0005]

In order to achieve such an object, in the present invention, a parallel strip in which an insulator is provided between a pair of parallel ground conductors and a center conductor is provided inside the insulator. The connection structure of the line cable
At the end of the parallel stripline cable, a notch is formed to expose the central conductor along its extension direction,
A hot line of a member to be connected is brought into contact with the central conductor exposed by the notch to connect the two.

[0006]

According to the above construction, since the hot line of the member to be connected is brought into contact with the exposed central conductor to connect it, the central conductor of the parallel strip line cable can be directly connected to the member to be connected.

Further, since the notch is formed, the thickness of the terminal portion is correspondingly reduced.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a partially cutaway perspective view of a parallel stripline cable according to an embodiment of the present invention.

The parallel stripline cable 1 includes a pair of ground conductors 2, which face each other in close proximity and are narrowly formed.
2, an insulator 3 filled in a portion surrounded by the ground conductors 2 and 2, and a central conductor 4 embedded in the insulator 3. That is, the parallel stripline cable 1 is configured by extending the center conductor 4 surrounded by the insulator 3 and the ground conductors 2 and 2 along the signal transmission direction. The insulator 3 is made of a plastic or flexible insulating material in order to give the parallel stripline cable 1 flexibility.

The parallel stripline cable 1 having the above-mentioned structure can be downsized, in particular, reduced in height for the following reasons. That is, in the parallel stripline cable 1, the total thickness depends on the thickness and width of the central conductor 4. On the other hand, since the central conductor 4 can be made of a thin film such as a sputtering film or a vapor deposition film, it is relatively easy to reduce its thickness and width. Therefore, the thickness and width of the central conductor 4 can be reduced, and the thickness of the parallel stripline cable 1 can be reduced to reduce the height. For example, when the characteristic impedance is 50Ω, the center conductor 4 has a width of 0.3 mm and a thickness of 0.01 mm, and the total thickness is about 0.4 mm. This is about half the outer diameter of a coaxial cable with equivalent performance.

A notch 5 is formed in the terminal portion 1a of the parallel stripline cable 1 having such characteristics. The notch 5 is formed by removing the insulator 3 from one earth conductor 2 side until the center conductor 4 is exposed along the thickness direction of the insulator 3 and along the extending direction thereof. The notch 5 is provided over a predetermined length in the cable extending direction from the end surface of the terminal portion 1a.

The following parallel stripline cable 1
The structure for connecting the substrate to the substrate 10 having the microstrip line will be described with reference to FIGS. First, the hot line 11 provided on the front surface of the substrate 10 is extended to one end surface of the substrate 10, and the earth line 12 provided on the back surface of the substrate 10 is extended to the above-described one end surface position of the substrate to obtain the hot line. 11 and earth line 12
And are opposed to each other with the substrate 10 interposed therebetween.

Then, the notch 5 is directed to the surface of the substrate 10,
Further, the exposed central conductor 4 is made to face the end of the hot line 11 so that the parallel stripline cable 1 is brought into contact with the substrate 10. In this state, the center conductor 4 and the hot line 11, and the ground conductor 2 and the ground line 12 are electrically connected. As shown in FIG. 2B, this connection can be performed by a relatively easy method such as welding or soldering because the central conductor 4 is exposed, and the connection portion is compact because the connection structure is simple. become. Furthermore, since the insulator 2 of the terminal portion 1a is cut off until the central conductor 4 is exposed to form the cutout portion 5, the thickness of the terminal portion 1a is reduced to about half, and accordingly, the connecting portion of the parallel stripline cable 1 is reduced. Will be further miniaturized, especially the height will be reduced.

A coaxial connector 20 can be easily connected to the parallel strip line cable 1 as shown in FIG. In this case, the outer conductor flange 21 of the coaxial connector 20 is brought into contact with the end face 1a of the parallel stripline cable 1, and the inner conductor 22 of the coaxial connector 20 is brought into contact with the exposed center conductor 4. In this state, the center conductor 4 and the inner conductor 22, and the ground conductor 2 and the outer conductor flange 21 are connected by welding, soldering or the like. The coaxial connector 20 can be connected by a relatively easy method such as welding or soldering because the central conductor 4 is exposed, and the connection structure is simple and the height of the connection portion can be reduced. become.

By the way, the parallel stripline cable 1 is not limited to the one shown in FIG. 1, but as shown in FIG. 4A, a shield in which the entire circumference of the insulator 3 is covered with the ground conductor 2. Needless to say, it may be a parallel stripline cable of a type, or as shown in FIG. 4B, a parallel stripline cable formed by covering the entire cable with a laminate resin 41.

Further, as the structure of the terminal portion 1a, in addition to the structure shown in FIG. 1, the ground conductor 2 may be extended to the side surface of the terminal portion 1a as shown in FIG. As shown in (a), a coplanar line 43 including the central conductor 4 and the ground pattern 42 may be formed on the exposed central conductor surface 6 of the terminal portion 1a. Also,
In addition to this, the coplanar line 43 is formed.
As shown in FIG. 6 (b), the ground conductor 2 on the back surface of the terminal portion 1a may be deleted, and further, as shown in FIG. 6 (c), the ground conductor 2 may be extended to the side surface of the terminal portion 1a. You may let me out. 6 is a cross-sectional view showing a state in which the parallel strip line cable is cut along the line AA in FIG.

The connection between the parallel stripline cable 1 having the coplanar line 43 as shown in each of FIG. 6 and the connected member is made as shown in FIG.
That is, the hot line 45 is extended to the front end surface of the member to be connected (the substrate 44 in this example), and the ground patterns 46 are formed on both sides of the end portion of the hot line 45. Then, the hot side and the ground side of the coplanar line 43 are connected to the hot line 45 and the ground pattern 46, respectively. In FIG. 7, the terminal unit 1
Although the coplanar line structure of a is the same as that of FIG. 6A, it goes without saying that it may be the terminal portion 1a of the coplanar line structure shown in FIGS. 6B and 6C.

[0019]

As described above, according to the present invention, electrical connection can be performed with a simple structure in which a hot line of a member to be connected is brought into contact with an exposed central conductor to connect the same, and a cutout is formed. Therefore, the thickness of the terminal portion is also reduced accordingly. Therefore, it has become possible to reduce the size of the connection structure of the high-frequency transmission line, in particular, reduce its height.

Furthermore, since the member to be connected is brought into direct contact with the exposed central conductor to connect them, the effect of facilitating the connecting work can be obtained.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a parallel stripline cable according to an embodiment of the present invention.

FIG. 2 is a perspective view and a cross-sectional view showing a connection structure between a parallel stripline cable and a substrate according to an embodiment.

FIG. 3 is a cross-sectional view showing a connection structure between a parallel stripline cable and a coaxial connector according to an embodiment.

FIG. 4 is a cross-sectional view showing a modified example of the parallel stripline cable.

FIG. 5 is a cross-sectional view showing a modified example of the terminal portion.

FIG. 6 is a cross-sectional view showing a modified example in which a coplanar line is formed.

FIG. 7 is a perspective view showing a connection structure between a parallel strip line cable having a coplanar line and a substrate.

FIG. 8 is a cross-sectional view showing a structure of a conventional coaxial cable and connector.

[Explanation of symbols]

 1 Parallel Stripline Cable 1a Terminal Part 2 Earth Conductor 3 Insulator 4 Center Conductor 5 Cutout 10 Board 11 Hotline 20 Coaxial Connector 22 Internal Conductor

Claims (1)

[Claims] 1. A parallel stripline cable (1) in which an insulator (3) is provided between a pair of parallel ground conductors (2, 2) and a center conductor (4) is provided inside the insulator (3). Connection structure of the parallel stripline cable (1) terminal (1a)
A notch (5) is formed on the core conductor (4) to expose the central conductor (4) along the extending direction, and the connected member (10, 20 ,,) is formed on the central conductor (4) exposed by the notch (5). Four
A connection structure for a parallel stripline cable, characterized in that the hot lines (11, 22, 45) of 4) are brought into contact with each other to connect them.