JPS5929337Y2 - Connection structure between coaxial connector and strip line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a connection structure between a coaxial connector and a strip line formed on a substrate.

Coaxial cords or strip lines, which have a low floor and a simple structure, are practically used as transmission lines in the high frequency range from the VHF band to the microwave band.

A coaxial cord has a structure in which the inner conductor is placed in the center of a cylindrical outer conductor, and a stripline has a structure in which conductor plates or band-shaped conductors are arranged in parallel between insulating plates with low high frequency loss. Both are suitable for transmitting TEM mode signals.

Coaxial lines are typically used for long-distance transmission, and striplines are often formed and used as part of circuit elements such as electronic switch force directional couplers.

In either case, when the transmission signal is in a high frequency range, the characteristic impedance of the line and its munching must be fully considered.

When striplines are used as circuit elements and the circuit elements are interconnected, or when coaxial cords are used for signal transmission, impedance matching must be maintained between the striplines and coaxial cords. It is important to connect at this point.

Conventional coaxial connectors can be used as elements for connecting coaxial cords, and the problem ultimately lies in the connection structure between the coaxial connector and the strip line.

Conventionally, as shown in FIGS. 1 and 2, a metal piece 9 (a perspective view of 9 is shown in FIG. 2) is used to connect a center conductor (signal line) 12 of a coaxial connector 8 to a strip line formed on a substrate.

), and the connection between the outside (ground conductor) of the coaxial connector 8 and the ground conductor (earth pattern) formed on the board is made through a fixed part between the case 10 and the board 11 in which each of them is mounted. Generally, the method is to connect each

In order to obtain good impedance matching characteristics using the above method, it is difficult to set the shape and dimensions of the metal piece and the mounting position.

(b) Complete grounding cannot be achieved by grounding via the board fixing part provided in the case, and the mounting part must have a large area.

(c) The case must be a good conductor.

) is expensive due to the difficulty of the work.

Due to these drawbacks, it is difficult to easily obtain stable characteristics.

The object of the present invention is to eliminate the above-mentioned drawbacks and provide a connection structure that has a low profile and provides good electrical characteristics during normal operations.

The present invention will be explained below with reference to the drawings.

FIG. 3 shows a structural state in which a coaxial connector mounted outside the case and a board mounted inside the case are connected via a flexible printed board.

FIGS. 4 and 5 are diagrams showing the overall structure of a flexible printed board, which is the gist of the present invention.

In a high frequency signal input/output section, a coaxial connector 2 mounted on the outside of the case 1 and a board 6 mounted on the inside of the case 1 are connected.

Flexible for grounding the signal line of the center conductor 2a of the coaxial connector 2 and the ground line of the outer shell 2b of the coaxial connector 2 to the signal line of the strip line 6a formed on the substrate 6TK and the ground line of the ground conductor 6b, respectively. This is done through both ends of the signal line of the stripline 4 formed on the printed board 3 and the ground line of the ground conductor 5, respectively.

The impedance characteristics of the strip line 4 and the ground conductor 5 of the flexible printed board 3 are the same as those of the coaxial connector 2 and the board 6.
The matching characteristic of the impedance characteristic can be obtained by numerical calculation on the circuit.

Furthermore, the processing technology of the flexible printed board 3 is high, and the quality, reliability, and reproducibility through repeated production are particularly excellent.

'Therefore, a very stable connecting element is provided.

The flexible printed board 30 is a flexible printed board with copper foil on both sides, and the strip line 4 is connected through a 4° through-hole hole, and the ground conductor is connected through a 5° through-hole hole. .

Regarding the connection on the coaxial connector 2 side, a flexible printed board 3 is installed between the coaxial connector 2 and the case 10, and by tightening and fixing them together, a grounding line is formed through the outer shell 2b of the coaxial connector 2 and the grounding conductor 5 formed on the flexible flint board 3.
The tip portion 5b of is connected.

The signal line is connected to the center conductor 2a of the coaxial gonnector 2 by inserting the connection hole 4b provided in the strip line 4 of the flexible printed board 3 and soldering the connection hole 4b.

Next, regarding the connection on the board 6 side, the signal line is connected by soldering the tip end 4a of the strip line 4 formed on the flexible print 1 [3 to the strip line 6a [formed on the board 6].

The ground line connects the tip 5a of the ground conductor 5 formed on the flexible printed board 3 to the ground conductor 6 formed on the board 6.
Connect by soldering to b.

In addition, the slin doors provided on the ends 4a and 5a of the flexible printed board 3 can be connected to the slip line 6a and the ground conductor 6b formed on the front and back sides of the board 60 even in the front and back directions. The purpose of this is to provide a degree of freedom in design.

According to the present invention, when there is a distance between the coaxial connector and the stripline formed on the board, the stripline can be connected by a stripline on the flexible printed board, which allows the setting of the stripline to match the impedance characteristics of both by pre-calculation. By doing so, the connection between the coaxial connector and the strip line on the board becomes perfect without any special consideration during mounting, and good characteristics can be obtained, especially in the high frequency range.

Furthermore, at this time, regarding the ground side of the flexible/full printed board, one side is fastened to the base of the coaxial connector, and a slit is provided on the other side, so that strip lines are formed on the front, back, and tilted sides of the board. Alternatively, connection to the ground pattern can be made from either the front or the back.

Furthermore, according to the present invention, the case 1 does not necessarily have to be made of a conductive material, and the degree of freedom in designing circuit elements is significantly increased, and the effects on electrical characteristics, economy, versatility, etc. are obvious.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing a conventional method of connecting a coaxial connector mounted outside the case and a board mounted inside the case via a metal piece, and Figure 2 is a perspective view of the metal piece shown in Figure 1. , Figure 3 is a cross-sectional view showing the structural state in which the coaxial connector mounted outside the case and the board mounted inside the case are connected via a flexible printed board, and Figure 4 shows the overall structure of the flexible printed board front cylinder side. FIG. 5 is a plan view showing the overall structure of the back side of the flexible printed board. In the figure, 1 is the tooth, 2 is the coaxial connector, 21 is the center conductor of the rachis connector, 2b is the outer shell (outer conductor) of the coaxial connector, 3 is the flexible printed board 14, 6 is the strip line, and 4a is the flexible print. the tip of the plate,
4b is the connection hole for the strip line, 4 (2e 5 c
5.5a and 5b are the tips of the ground conductor, 6b is the ground conductor, 6 is the substrate, and 7 is the slit.

Claims (1)

[Scope of utility model registration request] The center conductor of the coaxial connector and the outer shell of the coaxial connector are integrally connected to the strip line and the ground conductor formed on the board via first and second strip lines formed on the flexible printed board, and By providing a thrift on the board connection side of the flexible printed board, it is possible to connect from either the front or back to the strip line formed on the front, back, or tilted surface of the board. Features a connection structure between coaxial connectors and strip lines.