JPH1084214A - Built-in antenna of high frequency device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To omit the parts exclusive for an antenna and also the antenna attachment space and to miniaturize a high frequency device by providing the antenna conductor patterns on a pair of printed boards and forming a loop antenna by means of the connecting pins. SOLUTION: The antenna conductor patterns 5 and 6 are provided on a pair of printed boards 1 and 2 respectively, and a loop antenna consists of these patterns 5 and 6 and the connecting pins 3 and 4. It is desirable to form an L-shaped loop antenna where both pins 3 and 4 are positioned diagonally to each other together with both patterns 5 and 6 placed at the point symmetrical positions to each other. As a loop antenna having a small deflection of directivity is easily produced in such a way, the parts exclusive for the antenna and the antenna attachment space can be omitted. Thus, it is possible to inexpensively produce a built-in antenna that is suitable for the miniaturization and the improvement of sensitivity of a high frequency device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a built-in antenna built in a small high-frequency device such as a keyless entry for a vehicle to form a loop antenna.

[0002]

2. Description of the Related Art Among antennas built in a small high-frequency device, in particular, in the case of a receiving antenna, it is necessary to form a loop antenna having a small deviation in directional characteristics. Therefore, as a built-in antenna capable of forming such a loop antenna relatively inexpensively, conventionally, a highly rigid wire material such as a piano wire is bent three-dimensionally and mounted on a printed circuit board, and the antenna provided on the printed circuit board is provided. A structure in which the wire is connected to a circuit is widely used.

[0003]

However, in the above-mentioned conventional built-in antenna, a mounting space dedicated to the antenna must be ensured on a printed circuit board. Therefore, if the miniaturization of the high-frequency device is promoted, the space factor is degraded. As a result, there is a problem that the miniaturization of the high-frequency device is easily hindered.

[0004]

SUMMARY OF THE INVENTION According to the present invention, an antenna conductor pattern is provided on a pair of printed circuit boards which are arranged in mutually opposing positional relations and are connected by a plurality of connection pins. A loop antenna is formed with the connection pins, and a dedicated component for the antenna and a mounting space are omitted, so that miniaturization of the high-frequency device can be promoted.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a built-in antenna of a high-frequency device according to the present invention, a first printed circuit board provided with a first antenna conductor pattern and a second printed circuit board provided with a second antenna conductor pattern are provided. A plurality of connection pins for connecting the first printed circuit board and the second printed circuit board in opposing positional relations, wherein both ends of the first antenna conductor pattern are connected to one end of each of the pair of connection pins. , And both ends of the second antenna conductor pattern were connected to the other ends of the pair of connecting pins. At this time, the arrangement of the pair of connecting pins is in a diagonal positional relationship, and the first antenna conductor pattern and the second antenna conductor pattern are substantially L-shaped in a positional relationship symmetrical with each other. A pattern is preferable.

The built-in antenna having such a configuration can be applied to a small-sized high-frequency device by arranging the first and second printed boards facing each other, and the antenna conductor provided on each of these printed boards is provided. The loop and the connecting pin for mechanically connecting the two printed boards can easily form a loop antenna having a small deviation in the directional characteristics, so that a dedicated antenna component is not required, and a mounting space dedicated to the antenna is omitted. it can. Therefore,
A built-in antenna suitable for promoting miniaturization of a high-frequency device and having good sensitivity can be manufactured at low cost.

[0007]

Embodiments will be described with reference to the drawings.
FIG. 1 is a schematic perspective view of a substrate unit of the high-frequency device, and FIG. 2 is an explanatory diagram of the shape of the built-in antenna shown in FIG.

In FIG. 1, reference numeral 10 generally indicates a board unit of a small high-frequency device. The board unit 10 has a two-story structure in which a first printed board 1 and a second printed board 2 are arranged in a facing relationship and connected by a pair of conductive connecting pins 3 and 4. By doing so, the outer dimensions can be significantly smaller than those with a structure that uses only one printed circuit board,
This is advantageous in promoting downsizing of the high-frequency device. A substantially L-shaped first antenna conductor pattern 5 extending along two adjacent sides is provided on the substantially rectangular first printed circuit board 1. Both ends of the antenna conductor pattern 5 are a pair of Each of the connecting pins 3 and 4 is soldered to one end thereof. Similarly, a substantially L-shaped second antenna conductor pattern 6 extending along two adjacent sides is provided on the substantially rectangular second printed circuit board 2, and both ends of the antenna conductor pattern 6 are paired. Are connected to the other ends of the connecting pins 3 and 4, respectively. However, a pair of connecting pins 3,
4 are arranged in a diagonal positional relationship as shown in the figure.
The first antenna conductor pattern 5 and the second antenna conductor pattern 6 are substantially L-shaped patterns having a symmetrical positional relationship with each other with respect to the center of the board unit 10 as a reference point, as shown in the figure. Accordingly, the first and second antenna conductor patterns 5 and 6 and the connection pins 3 and 4 form a three-dimensional loop antenna 7 having a shape as shown in FIG. 10 is an integrated antenna.

The antenna conductor patterns 5, 6 are connected to an antenna circuit (not shown) provided on the first or second printed circuit board 1, 2.

As described above, the present embodiment not only reduces the size of the high-frequency device by employing the substrate unit 10 having a two-story structure, but also uses the loop antenna 7 (built-in antenna) without using a dedicated antenna component. And the installation space dedicated to the antenna is omitted, so that it is possible to manufacture a compact high-frequency device whose height is minimized. That is, the loop antenna 7 includes the first and second loop antennas.
And the connecting pins 3 and 4 for mechanically connecting the printed circuit boards 1 and 2 to each other, the antenna-specific parts are not required. Therefore, it is an inexpensive built-in antenna that can be assembled without increasing the number of parts and the number of assembly steps. Also, this loop antenna 7
Since has a shape as shown in FIG. 2, the deviation of the directional characteristics is small, and good sensitivity can be expected.

In the above-described embodiment, the first and second connection pins 3 and 4 only forming part of the loop antenna 7 are used.
The printed circuit boards 1 and 2 are connected to each other, but appropriate portions (for example, corners where the connection pins 3 and 4 are not present) of the printed circuit boards 1 and 2 are further connected by another connection pin to improve the mechanical strength. May be increased.

[0012]

The built-in antenna of the high-frequency device according to the present invention is embodied in the form described above, and has the following effects.

An antenna conductor pattern is provided on each of a pair of printed circuit boards arranged in a positional relationship facing each other and connected by a plurality of connection pins, and a three-dimensional loop antenna is formed by these antenna conductor patterns and the connection pins. Because it is formed, the antenna-specific parts are not required, the mounting space dedicated to the antenna can be omitted, and a loop antenna with a small deviation in directional characteristics can be easily formed.
Therefore, a built-in antenna suitable for promoting miniaturization of a high-frequency device and having good sensitivity can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a substrate unit of a high-frequency device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a shape of a built-in antenna shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st printed circuit board 2 2nd printed circuit board 3, 4 Connection pin 5 1st antenna conductor pattern 6 2nd antenna conductor pattern 7 Loop antenna (built-in antenna) 10 Board unit

Claims (2)

[Claims] 1. A first printed circuit board provided with a first antenna conductor pattern, a second printed circuit board provided with a second antenna conductor pattern, and the first printed circuit board and a second printed circuit board A plurality of connecting pins for connecting the substrates in opposing positional relations, wherein both ends of the first antenna conductor pattern are connected to one ends of a pair of the connecting pins, and the second antenna conductor pattern Characterized in that both ends of the high-frequency device are connected to the other ends of the pair of connecting pins. 2. The device according to claim 1, wherein the pair of connecting pins are arranged in a diagonal positional relationship, and the first pin is arranged in a diagonal manner.
Wherein said antenna conductor pattern and said second antenna conductor pattern are substantially L-shaped patterns having a symmetrical positional relationship with each other.