JPS5853232A - Wristwatch type radio receiver - Google Patents

Abstract

PURPOSE:To incorporate a radio receiver into a wristwatch without changing the conventional form of the wristwatch, by assembling an antenna inductor constituting a high frequency tuning circuit to a watchband and carrying out the tuning operation by means of a knob equivalent to a crown of the wristwatch. CONSTITUTION:An inductance 7 is adhered fixidely to a connecting metallic parts 16 of a watchband 15 via an insulator 17. The inductance 7 constitutes a tuning circuit and at the same time serves as an antenna. A shaft 22 provided to a wristwatch main body 14 is formed into a knob having a corm of a crown. This knob is turned to vary the resistance value of a variable resistor 10 to vary the voltage to be applied to a varactor. Thus the capacity value is changed, and then the harmonic voltage is varied. A microminiature variable capacitor, a voltage variable inductor or a miniature rotary variable inductor is applicable to a frequency selecting means.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radio receiver built into a wristwatch.

In recent years, wristwatches have changed from conventional mechanical analog displays to electronic digital displays. This is largely due to LSI technology, especially 0MO8LSI technology.

Electronic digital watches are superior to traditional mechanical watches in terms of accuracy, price, and functionality. In terms of functionality, it is not only the diversification of clock functions, but also the pronunciation of melody sounds for alarms, and the generation of the time using a human voice that is made possible by the combination of a voice synthesis LSI and a clock LSI made possible by LSI technology. Functions other than clocks, such as digital display of , pulse rate, and body temperature, have also been put into practical use.

On the other hand, with regard to radio receivers, LSI technology and the miniaturization of electronic components have made it possible to incorporate built-in radio receivers, but various problems still remain. That is, the main parts constituting the radio receiver are an antenna 1, as shown in FIG. High frequency tuner 2. High frequency amplifier 3. Detector 4. They are a low frequency amplifier 5 and a speaker 6. Among these, high frequency amplifier 3. Detector 4. The low frequency amplifier 5 can be integrated into an integrated circuit. Regarding speaker 6,
Although the sound quality is currently not satisfactory, it has already been put to practical use in the aforementioned melody pronunciation and voice synthesis vocalizations, so there is no problem with incorporating it into wristwatches. Furthermore, in some cases, earphones connected to the outside may be used without any practical problems. Rather, it is practical when considering the power battery capacity of the wristwatch.

However, the high frequency tuner 2 uses a tank circuit consisting of an inductance and a capacitor, and the shape of the inductance is large, making it difficult to incorporate it into a wristwatch. on the other hand,
A capacitor fixes the radio station selection, and there is no problem if you can only receive one station, but if you want to select multiple stations, you have to use a variable capacitor, which also has a problem due to its shape. . Furthermore, the means of actually operating this is also a problem. Although it is possible to use a short rod antenna or a human body as the antenna l, the sensitivity would be extremely poor.

The present invention solves the problems when these radio receivers are built into wristwatches, and two embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a circuit diagram of a main part of an embodiment of the wristwatch-type radio receiver of the present invention.

In Fig. 2, 7 is an inductor that constitutes a tuner.
It is formed by tightly winding a coil around a magnetic material such as ferrite. This inductance 7 forms a tuning circuit and also serves as an antenna, and is placed outside the wristwatch body. On the other hand, the tuning capacitor is a diode or varactor 8 whose capacitance changes depending on the applied voltage.
Use. A voltage for changing the capacity of the varactor 8 is applied to one terminal of the varactor 8 by dividing the voltage of the battery 11 by a variable resistor 10 . The capacitor 9 is used to lower the impedance of the voltage application line, and the inductor 7 and varactor 8 constitute a variable tuning circuit. This tuning circuit is connected to a high frequency amplifier 13 by a coupling capacitor 12, and is composed of a wave detector, a low frequency amplifier, and a speaker (not shown in the figure below).

FIG. 3 shows a schematic configuration example in which these circuits are implemented in a wristwatch. In the figures, (A) is a plan view thereof, and (B) is a cross-sectional view of the main parts, 14 is the main body of the wristwatch, and 15 is a band. Reference numeral 16 denotes a connecting fitting for coupling the bands on both sides, and 7 denotes a tuning inductor which also serves as an antenna as explained in FIG. 2, and is adhesively fixed onto the connecting fitting 16 via an insulator 17. Of course, if the connecting fitting 16 itself is an insulator, the insulator 17 is not necessary. Furthermore, since the connecting fitting 16 is fixed rather than bending like a normal band portion, it is convenient for fixing the inductor 7.

Therefore, assuming the shape of the inductor 7, the antenna effective length Ht indicating its performance is calculated. The inductor (5) 7 is a coil wound around a magnetic material as shown in FIG.

Here, and t represent the cross-sectional dimensions of the magnetic material, and assuming that the coil winding width and the length of the magnetic material are approximately equal, the effective length of the antenna is Ht = 2πNAμ/λ...・・・・・・
・Represented by (1).

However, A is the cross-sectional area of the magnetic material (tXt), N is the number of coil turns, μ is the effective permeability of the magnetic material, and λ is the wavelength of the radio wave (λ = 2π
f and f are the frequencies of radio waves).

Then, assuming the following as practical values, the effective length is determined from equation (1). That is, t == 5 mm + L
=10■, N=100T, μ=10. f=500kH
z, H7#5.2X10 m When Hz = 1 rB, effective long gain GA = Od
For B, Gt average 201og (5,2X10-') -66dB, Here, if the coil Q = 100 and the input electric field is 40 dB, the input to the amplifier Fin = -
66+40+40=14dB, which is a realistic input level (6).

Therefore, it is clear that if the inductor 7 also has the above-mentioned dimensions, it can be attached to the band 15 without any problem.

Next, the two lead wires 18 from the inductor 7 are connected along the band 15 to one terminal of the varactor 8 (see FIG. 2) in the main body 14 or to a ground wire.

In the embodiment, the antenna (also used as an inductor) 7 is attached to the connection fitting 16 of the band 15, but it is of course possible to attach it to a part of the band 15.

On the other hand, the main body 14 includes a printed circuit board 21 on which a liquid crystal display section 2θ for displaying time, a clock circuit LSI, an electric circuit IC for a radio receiver, a tuning varactor 8 (see FIG. 2), etc.
, and a variable resistor 10 that generates a voltage to vary the capacitance of the varactor. Note that the variable resistor 10 used is a thin round one. and variable resistor 1
0 is rotated by rotating a gear attached to a rotating shaft at the center of the variable resistor 10 using a shaft 22 with a worm gear attached to the tip. Further, a rotation stop knob is attached to the other end of the shaft 22, and extends outside the main body cover. This has the same form as the spring provided in conventional mechanical watches for setting the time and winding the mainspring. Therefore, this IJ, - acts as a frequency tuning knob of a radio receiver.

As is clear from the above description, if the antenna and tuner are constructed according to the present invention, a wristwatch with a built-in radio receiver can be constructed.

In the above embodiment, a varactor is used as the variable tuning element of the high frequency tuning circuit, but it may also be a micro variable capacitor, a voltage variable inductor, or a small rotary variable inductor. However, in the case of an inductor, if an inductor that is part of the tuning circuit is used in the antenna, a variable inductor is added to it and it is no longer used, so naturally the variable range of the tuning frequency becomes narrower. The purpose of the shaped radio receiver is achieved. Here, there is a problem that the reception frequency range is narrow due to the use of a varactor as a tuning element.

That is, in the case of the Dinotal wristwatch, the power supply voltage for driving the clock circuit is only 3V, and it is difficult to cover the entire reception frequency range with this voltage. For example, in the case of the AM band, it is necessary to cover 520 kHz to 1610 kHz, and the capacitance change ratio in this case needs to be about 9 times. Since it is difficult to cover this change ratio with one varactor within the applied voltage range of 3 V or less, two varactors 8a and 8b are used to cover this as shown in FIG. First, in the region where the frequency is low, the two varactors 8
A and 8b are connected in parallel, and one is cut off in the middle of the frequency band and used alone. In this way, a wide frequency range can be covered even at low voltage. Furthermore, even if a plurality of varactors are used, they can be integrated into a single chip using semiconductors, so there is no problem of storage space.

In this first embodiment, an antenna inductor that forms a high-frequency tuning circuit is attached to the watch band, and the tuning operation is performed using the knob (9), which corresponds to the leash of a conventional wristwatch. A radio receiver can be built-in without impairing the shape or function. In the first embodiment, the tuning voltage for changing the reception frequency was generated by directly changing the variable resistor, but this voltage can also be generated by a dinotal circuit.

FIG. 6 is a circuit diagram showing this second embodiment, in which dinotal data generated by a counter is successively converted into an analog voltage by a DA converter and applied to a varactor.

That is, 23 is a clock oscillator for changing the speed at which data is generated, and the clocks generated from this clock oscillator 23 are counted by an up/down counter 24. Note that the up/down counter 24 is connected to the switch 2 in the direction in which the output data increases and in the direction in which the output data decreases.
It is switched by 5. That is, when the switch 25 is turned up, the r-value of the counter 24 increases sequentially, and when the switch 25 is turned down, the data sequentially decreases. counter 24
The output data is converted into an analog voltage by the D/A converter 26 (10), and is applied to the varactor 8 of the tuning circuit through the smoothing circuit 27. When tuning, the radio can be tuned by operating the switch 25. Another advantage of this method is that, although there is a problem of interference with radio receivers due to the generation of some noise from the Dinotal circuit, the entire circuit can be integrated into an LSI, making it easy to incorporate it into a wristwatch. Note that in the first embodiment, there is no influence of noise interference at all. In the second embodiment, the operation for tuning only requires the addition of one small push button switch. In other words, each time the depress switch is pressed once, the amplifier and down switches are alternately repeated.

As explained in detail above, the present invention attaches an antenna inductor forming a high frequency tuning circuit to a watch band,
Since the tuning operation is performed by a knob corresponding to the leash of a conventional wristwatch, it is possible to incorporate a radio receiver without changing the shape of the conventional wristwatch. Therefore, it can be applied to increasing the functionality of wristwatches and miniaturizing radio receivers.

[Brief Description of the Drawings] Fig. 1 is a block diagram of a radio receiver, Fig. 2 is a main circuit diagram showing an embodiment of the wristwatch-type radio receiver of the present invention, and Fig. 3 is a block diagram of a radio receiver.
The figures are schematic configuration diagrams showing one embodiment of the wristwatch-type radio receiver of the present invention, (A) is a plan view thereof, (B) is a sectional view of the main parts thereof, and FIG. 4 is a perspective view showing the antenna inductor. FIGS. 5 and 6 are main circuit diagrams showing other embodiments of the receiver of the present invention. l... Antenna, 2... High frequency tuner, 3... High frequency amplifier, 4... Detector, 5... Low frequency amplifier, 6
... Speaker, 7 ... Antenna inductor, 8, 8a
+8b...Varactor, 13...High frequency amplifier, 14
...Main body of the wristwatch, 15...Band, 16...Connection fittings, 17...Insulator, 18...Lead wire, 20
...Liquid crystal display section, 21...Printed circuit board, 22...
Shaft, 23...Clock oscillator, 24...Amplifier down counter, 25...Switch, 26...D
/A converter, 22... smoothing circuit.

Claims (5)

[Claims] (1) A wristwatch-shaped radio receiver in which a radio receiver is built into a wristwatch, characterized in that the wristwatch's leash is combined with frequency selection means. (2) A wristwatch-type radio receiver according to claim 1, wherein the frequency selection means is a variable capacitor or a variable inductor. (3) The wristwatch-type radio receiver according to claim 1, wherein the frequency selection means is a variable resistor and a varactor to which a voltage is applied by the variable resistor and functions as a variable capacitor. (4) The wristwatch-type radio receiver according to claim 1, wherein the frequency selection means includes a variable resistor, a plurality of varactors, and means for switching and connecting the varactors, and switches and tunes within the reception frequency band. (5) The frequency selection means includes a clock oscillator, a counter that counts the frequency of the oscillator, a D/A converter that converts the output of the counter into a D/A converter, and applies an output analog voltage of the D/A converter. A wristwatch-type radio receiver according to claim 1, which includes a varactor.