JPS61181203A - Wrist strap type antenna system - Google Patents

Abstract

PURPOSE:To obtain an antenna system having portability, sufficient resonance length and directivity by providing imbedding a flexible metallic plate into a resin wrist strap of a wrist watch and providing a connector to one end. CONSTITUTION:A wrist strap 2 is made of a type of material such as polystyrene and has a thin plate metallic piece 9 at its middle part. A tongue piece 12 formed at the end of the strap 12 has the plate metallic piece 9 being a part of an antenna and a male type metallic fixture 11 for connector terminating the piece 9 at its inside and is connected electrically and mechanically to an antenna circuit comprising a loading coil and a tuning circuit or the like formed in the inside of a main body 1, and also attached/detached freely, and half-buried in a ditch 8 formed to the main body 1 so as not to give any inconvenience to the wrist mounting, and has expanding and contracting property so that the strap 2 is turned smoothly to the main body 1. The antenna plays a role of a loop antenna at mounting.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a band-type antenna device that can be used for wrist watches such as radio watches and television watches.

[Prior art]

In recent years, with the advent of radio watches and television watches, wristwatches, which are usually the only electronic devices worn by humans, have become increasingly sophisticated.

However, the earphones and antennas that are attached to these devices are not portable or inconvenient. For example, in Radio Watch, if it is an AM broadcast, the antenna is omitted and the reception is completely dependent on the tuning circuit, and if it is an FM broadcast, a separate external antenna is usually provided. It is. Also, TV A
When it comes to Tsuji, most of the main circuitry, including the antenna, is a separate device, and the wristwatch part is sometimes used as a mere display device.

Now, when a person walks in a city and receives radio broadcasts or television broadcasts, the noise in the city is a mixture of both noise and radio noise. Therefore, for the former, earphones
For the latter, antennas play an important role in eliminating the noise.

In particular, antinos are preferably directional or have a length close to the resonant wavelength, since the higher the receiving frequency, the more linear the radio waves become.

However, since the resonance wavelength is longer as the frequency is lower, it is difficult and extremely inconvenient to attach an antenna with a length close to the resonance wavelength to the wristwatch. For example, the frequency of 900 M I-I z is 1 wavelength 33
cm, and it is impossible to attach a 33 cm antenna to a wristwatch.

[Purpose of the invention]

The present invention has been made in consideration of the above circumstances, and aims to provide a band-type antenna device that can be installed in a wristwatch, has portability, and has sufficient resonance length and directivity. .

[Summary of the invention]

In order to achieve the above object, the band type antenna device according to the present invention includes a resin band with a flexible metal plate embedded therein, and an electric connection formed at one end of the resin band to the metal plate. and an antenna circuit connected to the connector.

[Embodiments of the invention]

A band type antenna device according to an embodiment of the present invention is shown in FIGS. 1 and 2. FIG. 1 shows a wristwatch equipped with a band-type antenna device according to this embodiment, and one side of the band is omitted for the sake of explanation. Figure 1 (
Figure 1 (a) is a rear view of this wristwatch, and Figure 1 (b) is a rear view of this wristwatch.
) is a side view. A band portion 2 is attached to a main body 1 of the wristwatch.

The band portion 2 is formed to have a wider width as it approaches the main body 1. A plurality of holes 3 are formed to connect the band parts 2 to each other, and a hole (not shown) through which a metal shaft 4 is passed in order to mechanically connect the band parts 2 to each other and make them movable is provided at one end. There is. The main body 1 also has a crown 5, a back cover 6, a female connector fitting 7, and further has a recess 8 formed therein.

A sufficiently thin and flexible metal plate 9 constituting a part of the antenna and a metal plate 10 formed on the extension of the band part 2 by going around the hole 3 are embedded inside the band part 2, and a connector is attached to one end. A male fitting 11 is formed. The main body 1 and the band portion 2 are preferably made of a material such as polystyrene, which has low dielectric loss.

In particular, the band portion 2 has sufficient flexibility, but
Even with the thin plate-shaped metal piece 9 in the center, it is formed so as to still maintain sufficient flexibility and not impair its function as a band.

The tongue piece 12 formed at the end of the band portion 2 has a structure unique to the present invention, and has inside thereof a plate-shaped metal piece 9 that is a part of the antenna and a male connector fitting 11 that terminates the plate-shaped metal piece 9. death,
It is electrically and mechanically coupled to the antenna circuit formed inside the main body 1 and is detachable. Also tongue piece 1
2 is half embedded in a recess 8 formed in the main body 1 so as not to become an obstacle when the wristwatch is worn on the wrist. Also, as the tongue piece 12 expands and contracts, the main body 1
The band portion 2 is configured to rotate smoothly relative to the belt.

As shown in FIG. 1(b), as main parts of the antenna circuit inside the main body 1, a loading coil 13 and a high frequency power supply or tuning circuit 14 are each connected in series to a female connector fitting 7.

The loading coil 13 is for extending the resonance length of the antenna. The ferrite 15 is loaded into the rhodeink coil 13 and used to lower the resonant frequency of the entire antenna.

FIG. 2 is a schematic diagram of the electrical circuit that forms a loop antenna when this wristwatch is actually worn on the wrist. The area designated by the reference numeral 16 in FIG. 2 indicates the area of the body 1 of FIG. The connection between the female fitting 7 and the male fitting 11 in FIG. 1 is as indicated by reference numeral 17.

A plate-shaped metal plate 9 constituting the band-type antenna device shown in FIG.
and 10 are represented in FIG. 2 as elements 18 of a loop antenna.

The plate-shaped metal plate 10 in FIG. 1 forms a short-circuit portion 19 for high-frequency signals when a pair of bands are coupled using the holes 3. Therefore, the second base body becomes a loop antenna corresponding to the thickness of the arm, and its directivity has a gain perpendicular to the plane of the paper. The human body acts as a lossy dielectric and affects the resonant frequency, but this is not a big problem at low frequencies. The ferrite 15 can also be used to finely adjust the resonant frequency of the antenna depending on the thickness of the arm.

If the wristwatch is required to have additional functions, for example as a radio wave transmitter, the band antenna device according to this embodiment will play an essentially important role.
Because the wristwatch is small, it can only transmit weak radio waves, and the directivity and resonance characteristics of the antenna will generate effective radiation.

If the wristwatch emits weak radio waves intermittently using a cord, power consumption can be significantly reduced, and the watch can also be powered by a small battery.

In the above embodiment, the loading coil 13 and the ferrite 1
5 is provided on the main body 1, but it may also be provided on the band portion 2. Further, in the above embodiment, a wristwatch band is used, but other bands such as a headband band may also be used.

〔Effect of the invention〕

As described above, according to the present invention, even if the wristwatch has the function of transmitting and receiving radio waves, the appearance remains the same as that of the conventional wristwatch without using a separate auxiliary antenna. can do.

Therefore, it is possible to make the wristwatch 1 to have multiple functions, such as adding a personal identification function and a bell function to the watch 1.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a band-type antenna device according to an embodiment of the present invention, and FIG. 2 is a diagram showing how a loop antenna is constructed when the band-type antenna device is actually worn on the arm. 1... Main body of the wristwatch, 2... Band part, 3
... Connection hole, 4... Connection fitting, 5... Crown,
6... Back cover, 7... Female metal fitting, 8... Recess, 9
... Metal plate, 10... Metal plate, 11... Male metal fitting, 12... Tongue piece, 13... Loading coil,
14... High frequency power supply or tuning circuit, 15... Ferrite. -Q - - 1 8 -

Claims (1)

[Claims] 1. A resin band with a flexible metal plate embedded therein, a connector formed at one end of the resin band and electrically connected to the metal plate, and a connector connected to the connector. What is claimed is: 1. A band-type antenna device comprising: an antenna circuit; 2. The device according to claim 1, wherein the antenna circuit includes a loading coil connected to the connector and a high frequency power source connected to the loading coil. . 3. The band-type antenna device according to claim 1, wherein the antenna circuit includes a loading coil connected to the connector and a tuning circuit connected to the loading coil. . 4. A band-type antenna device according to claim 2 or 3, wherein the antenna circuit includes a ferrite loaded in the loading coil. 5. The device according to any one of claims 1 to 4, characterized in that the one end of the resin band is formed with a mechanical connection part independent of the connector. Band type antenna device.