JP2548490Y2 - Antenna device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an antenna device for transmitting and receiving radio waves, and more particularly to a small antenna device built in a high-frequency device and suitable for transmitting and receiving high-frequency signals.

[Prior art] For high-frequency equipment for transmitting and receiving ultrashort or ultrahigh frequency such as 300 MHz, linear antennas or planar antennas are widely used, and fields where miniaturization is required such as portable equipment In order to reduce the size of the antenna, a 1 / 4λ linear antenna, a planar pattern antenna, and the like are widely used.

[Problems to be solved by the invention]

In the case of a linear antenna, one end is fixed on the mounting board of the electric component. However, when the size and thickness of the device are reduced, the interference between the antenna and peripheral components and peripheral devices increases. However, there is a disadvantage that the antenna has a large loss and the radiation efficiency is reduced. Also, in the case of the planar pattern antenna, there are disadvantages that the propagation loss is large and the radiation efficiency is reduced. Particularly, in the case of a system in which a high-frequency signal is transmitted to a receiver by turning on a switch, for example, a push button switch for opening and closing an automatic door, and the receiver controls the door to be opened by receiving the high-frequency signal. Incorporates a transmitter in the pushbutton switch, but this transmitter is as small and thin as possible, and the pushbutton switch is not bulky, but as the shape becomes smaller,
Since the radiation efficiency of the antenna becomes a problem, it greatly affects the performance of the device. In addition, so-called ID cards that transmit a specific code signal to identify the owner in order to identify the entrance to an automatic door or a specific department have been put into practical use, and a transmitter and antenna are built in such a card. To do so, it is required that the antenna be thin and small and that it can transmit radio waves efficiently.

Therefore, an object of the present invention is to provide an antenna device which has low coherence with peripheral devices and can transmit and receive radio waves efficiently.

[Means for solving the problem]

In order to achieve the above-mentioned object, the present invention provides two support substrates erected on a printed circuit board at predetermined intervals so that their surfaces are parallel to each other, and a predetermined interval at the upper end of these support substrates. A plurality of notches formed opposite to each other, and a tip antenna conductor disposed on the notch side located at one end of the plurality of notches; The rear end antenna conductor disposed on the side of the notch located at the other end of the pair of notches and a linear shape slightly longer than the length between the support substrates, and the plurality of notches A plurality of intermediate antenna conductors spanned between the remaining intermediate notches, and the tip antenna conductor is hung between the notches located at the one end. From the passed rear end, and one end of the rear end, each upper end of the support substrate A horizontal portion bent substantially at a right angle in an imaginary horizontal plane, and a tip portion bent at a substantially right angle downward from a predetermined portion of the horizontal portion toward the printed circuit board side and connected to an insulating land of the printed circuit board. The rear end antenna conductor has one end grounded, the other end locked in a notch located at the other end, and a side surface between the notches of the support substrate. Is characterized in that a strip line for electrically connecting the intermediate antenna conductor, the front antenna conductor, and the rear antenna conductor in series is formed.

[Action]

The antenna conductor is separated into an intermediate antenna conductor, a front antenna conductor, and a rear antenna conductor. However, since they are connected in series by a strip line of the support substrate, the antenna conductor becomes substantially one linear antenna, As well as constituting the horizontal polarization plane, the front end antenna conductor is bent substantially L-shaped at the rear end and the horizontal part, so that the electromagnetic radiation surface can have characteristics close to a heart shape at this part, The installation position of the equipment can be set freely. In addition, since this antenna conductor is mounted on a printed circuit board for mounting components of equipment while being supported by two support substrates, the antenna conductor is excellent in impact resistance and the height of the support substrate is adjusted. Accordingly, the height can be reduced as much as possible without being disturbed by components on the substrate.

〔Example〕

The present invention will be described below with reference to an embodiment shown in the drawings. On a printed circuit board 1 on which components (not shown) necessary for transmitting and receiving radio waves are mounted, two support substrates 2, 3 is erected so that their planes are parallel. A plurality of notches 4 are formed at predetermined intervals in the upper edges of the support substrates 2 and 3. These notches 4 are located opposite to the notches 4 of the other support substrate 2 or 3. Numeral 5 denotes an antenna conductor, two linear intermediate antenna conductors 6 slightly longer than the length of the gap between the support substrates 2 and 3, one front antenna conductor 7 and one rear antenna conductor 8 likewise. It is composed of

The tip antenna conductor 7 includes a rear end portion 11 that extends between the notch portions 4 located at the right end in the drawings of the support substrates 2 and 3, a horizontal portion 12 that is bent substantially at right angles from the rear end portion 11, and The horizontal portion 12 is bent downward at a substantially right angle from the end opposite to the rear end 11 to form a tip 13, and the tip of the tip 13 is an insulating land 14 formed on the printed circuit board 1. It is inserted into a hole 15 formed therein. One end of the rear end antenna conductor 8 is grounded, not shown, and the other end is locked in the cutout 4 on the left end of the support substrate 3 in the drawing. Each intermediate antenna conductor 6 is provided so that one end thereof is engaged with the notch 4 of the support substrate 2 and the other end thereof is engaged with the notch 4 of the support substrate 3. A strip line 16 for electrically connecting the intermediate antenna conductors 6 and 6 in series is formed between the cutouts 4 and 4 of the two intermediate antenna conductors 6 and 6 on the support substrate 2 side. The end of the conductor 6 is connected to the strip line 16 by soldering or the like. Similarly, between the end portion of the rear end portion 11 of the front end antenna conductor 7 located in the cutout portion 4 of the support substrate 3 and the end portion of the intermediate antenna conductor 6 adjacent to the rear end portion 11, and the rear end antenna A strip line 16 is also formed on the support substrate 3 between the end of the conductor 8 located at the notch 4 of the support substrate 3 and the end of the intermediate antenna conductor 6 adjacent to the rear end antenna conductor 8. These ends are electrically connected. Thus, the intermediate antenna conductor 6, the front antenna conductor 7, and the rear antenna conductor 8 are connected in series via the strip line 16. Reference numeral 17 denotes a feeder line, which passes from the rear end antenna conductor 8 through the strip line 16 to 50 Ω of the intermediate antenna conductor 6.
Connected to The entire length of the antenna conductor 5 is set so as to resonate with a 1 / 4λ component of the working frequency.

As described above, the antenna device according to the present embodiment can be mounted on the printed circuit board 1 for mounting components of a high-frequency device, and is obstructed by the components on the printed circuit board 1 by adjusting the height of the supporting substrates 2 and 3. It can be provided without the need. An antenna is constituted by a combination of a linear conductor formed by the antenna conductor 5 and a strip line 16, and a vertical polarization plane is constituted by a tip portion 13 of the tip antenna conductor 7, and a horizontal portion 12 and an intermediate portion of the tip antenna conductor 7 are formed. Since a horizontal plane of polarization is formed by the antenna conductor 6, radio waves can be transmitted and received widely. Further, the horizontal portion of the tip antenna conductor 7
Since the rear end portion 11 and the rear end portion 11 are bent at a substantially right angle, that is, an L-shape, the radio wave radiation pattern has a characteristic close to a heart shape, and a wide radio wave radiation surface can be obtained. Also feed line
The 17 connection points can be easily adjusted to reduce interference with each part and interference from the surroundings of the device. For example, it is possible to prevent radiation levels from changing due to approach of human hands, etc., and to improve stability. be able to.

[Effect of the invention]

As described above, the antenna device of the present invention forms a plurality of notches at a predetermined interval at the upper ends of two support substrates erected at a predetermined interval on the substrate. A plurality of intermediate antenna conductors, a front antenna conductor, and a rear antenna conductor, which are electrically connected in series by a strip line formed on a support substrate, and a board for mounting equipment parts. Can be directly mounted on the substrate, and by adjusting the height of the supporting substrate, the supporting substrate can be provided without being obstructed by components on the substrate and without being bulky. Therefore, the present invention is suitable for a device requiring a thin shape such as the switch portion of the automatic door as described above. Also, the tip antenna conductor has a rear end portion, a horizontal portion bent substantially at a right angle from the rear end portion, and a substantially right angle bent downward from an end portion facing the rear end portion of the horizontal portion at the front end portion. Because it is configured, the radio wave radiation pattern has a characteristic close to a heart shape, and a wide radio wave radiation surface can be obtained. Radio waves can be transmitted accurately without being performed.

[Brief description of the drawings]

The drawing is a perspective view showing an embodiment of the antenna device of the present invention. In the drawings, 1 is a printed circuit board, 2 and 3 are support substrates, 4
Is a notch, 5 is an antenna conductor, 6 is an intermediate antenna conductor, 7 is a front antenna conductor, 8 is a rear antenna conductor, 11
Is the rear end, 12 is the horizontal part, 13 is the tip, 14 is the insulating land,
Reference numeral 15 denotes a hole, 16 denotes a strip line, and 17 denotes a power supply line.

Claims (1)

(57) [Scope of request for utility model registration] 1. Two supporting substrates erected on a printed circuit board at predetermined intervals so that their surfaces are parallel to each other, and opposing each other at predetermined intervals at the upper ends of these supporting substrates. A plurality of notches formed in the tip antenna conductor disposed on the notch side located at one end of the plurality of notches, and the plurality of notches Inside, the rear end antenna conductor arranged on the side of the notch located at the other end, and a linear shape slightly longer than the length between the support substrates, and is left in the plurality of pairs of notches. A plurality of intermediate antenna conductors bridged between the notch portions located in the middle, and the front end antenna conductor has a rear end portion bridged between the notch portions located at the one end. And from one end of the rear end portion in a virtual horizontal plane including each upper end of the support substrate. A horizontal portion bent substantially at a right angle, and a tip portion bent substantially perpendicularly downward from a predetermined portion of the horizontal portion toward the printed circuit board side and connected to an insulating land of the printed circuit board; The rear end antenna conductor has one end grounded, the other end locked in a notch located at the other end, and a side surface between the notches of the support substrate with the intermediate antenna conductor. An antenna device, wherein a strip line for electrically connecting the front antenna conductor and the rear antenna conductor in series is formed.