JPH07221825A - Cordless communication equipment - Google Patents

Abstract

PURPOSE:To interrupt a communication circuit and to suppress production of howling by using the small sized equipment with a simple structure, detect a slave set approaching a charger. CONSTITUTION:A battery 15 built in a slave set 10 is charged by the contactless charging system adopting electromagnetic induction. That is, an AC magnetic field sent from an exciting coil 20 provided to a charger 18 is detected by a detection coil 24 built in the slave set and an AC power generated across the detection coil through the electromagnetic induction is fed to the battery to charge the battery via a rectifier circuit 25 and a reverse flow prevention diode 26. On the other hand, an output of the rectifier circuit is branched to a comparator 32, in which the output is compared with a reference voltage Vs. When the slave set approaches the charger, an output of the rectifier circuit increases. When the output exceeds the voltage Vs, an output of the comparator goes to an H level, a contact of a normally closed switch 34 connecting to a microphone 11 is opened to interrupt the communication circuit (bypass sound from a speaker 12 to the microphone 11 is eliminated).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cordless communication device, and more particularly to howling prevention.

[0002]

2. Description of the Related Art For example, in a cordless telephone in which a master unit and a slave unit are wirelessly connected, the master unit is used as a base unit and the slave unit is used as a handy unit at hand. As shown in FIG. 3, generally, the slave unit 1 when not in use (standby) is placed on the charger 2, and the slave unit 1 is connected via the charging terminal 2 a provided on the charger 2. It connects to the battery built in and charges the battery.

When the handset 1 is taken up from the charger 2, it automatically goes into an off-hook state and a communication circuit (external line / extension) is formed. On the other hand, when the handset 1 is set in the charger 2, the charging terminal 2a is set. Is detected to be electrically connected to a charging terminal (not shown) provided in the child device 1, and the communication circuit can be disconnected. The communication circuit is turned on / off when the handset 1
It can also be performed by operating the switch of the button operation unit provided on the.

[0004]

However, in the above-mentioned conventional apparatus, when the handset 1 is set close to the charger 2 after the call is finished, the handset 1 is reflected by the opposite surface of the charger 2 and the like. The speaker 1a may sneak into the microphone 1b to cause howling.

On the other hand, a proximity sensor composed of a hall element or the like is mounted in the handset 1, and the proximity sensor detects that the distance between the handset 1 and the charger 2 has approached the distance causing the above howling. It is also possible to turn off the communication circuit. However, with such a configuration, it is necessary to additionally provide a detection circuit such as a proximity sensor and a means for operating the proximity sensor must also be installed on the charger 2 side, which complicates the configuration. The size is increased and the cost is increased.

The present invention has been made in view of the above background. An object of the present invention is to solve the above problems and to provide a cordless communication device such as a cordless handset with a simple and compact structure. An object of the present invention is to provide a cordless communication device capable of detecting that a battery charger is approaching, disconnecting the communication circuit, and suppressing howling.

[0007]

In order to achieve the above object, in a cordless communication device according to the present invention, a voice detection means, a voice output means and a wireless means driven by an internal battery, and the internal battery are charged. Cordless provided with a detection coil capable of detecting a magnetic flux emitted from an excitation coil provided in the charger for charging, and charging means for charging the internal battery based on an induced electromotive force generated in the detection coil by electromagnetic induction. A communication device, which detects the induced electromotive force and detects that the cordless communication device approaches the charger, and outputs the output of the voice detection device based on the detection result of the detection device. And a cutting means for cutting.

Preferably, the detection means is composed of a comparator having the output voltage of the detection coil as an input, and more preferably, the reference voltage of the comparator is necessary for charging the internal battery. It is to set it lower than the voltage.

More preferably, the disconnecting means is at least one of a switch for reducing the sensitivity of the voice detecting means or for disconnecting the output of the voice detecting means from other circuits.

[0010]

When the communication device is set to the charger after a predetermined call is finished and the communication device is approached to a certain extent (close enough to cause howling) before being completely set, the magnetic flux generated from the exciting coil causes the detecting coil to move. Since it passes, an induced electromotive force is generated in the detection coil. Therefore, when the induced electromotive force is detected by the detection means, the output of the voice detection means is cut off. As a result, howling does not occur.

Further, when the detecting means is composed of a comparator, the value of the induced electromotive force (voltage) generated in the detecting coil is easily within a fixed distance range depending on whether the value exceeds a predetermined reference value. It is possible to know whether the communication device has arrived. Moreover, if the reference value is set lower than the voltage required to charge the internal battery, it is detected even when the charger is relatively far from the communication device (not far from the normal call state). Therefore, howling is reliably suppressed from occurring.

If the disconnecting means is at least one of a switch for lowering the sensitivity of the voice detecting means or disconnecting the output of the voice detecting means from other circuits, in either case, the voice generating means changes to the voice detecting means. The occurrence of howling that accompanies the wraparound is more reliably suppressed.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of a cordless communication device according to the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows a preferred embodiment of the present invention. As shown,
A microphone 11 as a voice detecting means and a speaker 12 as a voice output means are connected to a wireless circuit 13 as a communication means, and an antenna 14 connected to the wireless circuit 13 is provided in the slave unit 10.
Communicates with the base unit via the specified line (external line /
(Extension) is supposed to make a call. And each part 1
1 to 13 operate by receiving power supply from the battery 15.

Here, in the present invention, first, the battery 15 built in the slave unit 10 is charged by a non-contact charging method by electromagnetic induction. That is, the charger 1
8 is provided with an exciting coil 20 at a predetermined internal position, and a power cable 21 connected to the exciting coil 20 is connected to the commercial power source 2
By mounting it on the AC power source 2, AC power is supplied from the commercial power source 22 to the exciting coil 20.

Then, the AC magnetic field generated by the exciting coil 20 is detected by the detection coil 24 incorporated in the slave unit 10, and AC power is generated at both ends of the detection coil 24 by electromagnetic induction. Therefore, the rectifier circuit 25 formed of a diode bridge is connected between both terminals of the detection coil 24, and the battery 15 is connected to the output of the rectifier circuit 25 via the backflow prevention diode 26. As a result, when the slave unit 10 is set on the charger 18, the exciting coil 20 and the detecting coil 24 approach and face each other, and electromotive force is generated in the detecting coil 24 by electromagnetic induction, so that the battery 15 is charged. . The rectifying circuit 25, the backflow prevention diode 26, and the like constitute a charging means.

As shown in FIG. 2, the exciting coil 20 is wound around the body of a U-shaped core 28 for a predetermined number of turns, and is provided at one end of the upper surface of the charger 18 together with the core 28. Along the inner surface of the recess 29, the core 2
Both of the tip ends 28a of No. 8 are filled so as to be located on the recess 29 side. And the circumference is resin-molded.

On the other hand, when the cordless handset 10 is set in the charger 18, a receiver portion 10a in which a speaker of the cordless handset 10 is built is inserted and arranged in the recess 29, and the receiver portion 10a has the receiver portion 10a. The detection coil 24 is mounted. That is, the detection coil 24 is also wound around the body of the U-shaped core 30 for a predetermined number of turns, and the tip 30a of the core 30 is wound around the core 2 around which the exciting coil 20 is wound.
8 are arranged so that the tip ends 28a of the metal plates 8 face each other, and further, the metal plate 32 is arranged so as to cover the periphery of the core 30.
It is magnetically shielded. As a result, the exciting coil 20
The magnetic field generated by the detector coil 24 and received by the detection coil 24 is
It does not affect other circuits mounted on 0.

Although a specific configuration is omitted, a predetermined overcharge prevention circuit for preventing the battery 15 from being overcharged, or a communication line automatically when the slave unit 10 is removed from the charger 18. It also has the function of connecting.

In the present invention, the output of the rectifying circuit 25 is branched and input to one of the input terminals of the comparator 32, which is the detecting means. The reference voltage Vs is applied to the other input terminal of the comparator 32. When the output of the rectifier circuit 25 exceeds the reference voltage Vs, the comparator 3
The output of 2 becomes H, and it is adjusted so as to open the contact of the normally closed switch 34 which is a disconnecting means connected to the microphone 11. Then, when the normally closed switch 34 is opened, the communication circuit is disconnected (the wraparound from the speaker 12 to the microphone 11 is eliminated).

Next, the operation of the above embodiment will be described. First, in a normal call state, since the cordless handset 10 and the charger 18 are separated from each other, the magnetic force generated from the excitation coil 20 does not pass through the detection coil 24, and the battery 15 is charged without electromagnetic induction. I don't know. Although not shown, electric power is supplied from the battery 15 to each circuit in the child device 10 through a predetermined path. In addition, the comparator 32
Since the output of is also L, the contact of the normally closed switch 34 is closed. Therefore, the slave unit 10 can communicate with the master unit (not shown) by using the known mechanism, and the extension line call or the outside line call can be performed.

On the other hand, after the predetermined call is completed, the cordless handset 10 is set on the charger 18, and when it is approached to some extent (close enough to cause howling) before being completely set, the exciting coil is set. The magnetic flux generated from 20 passes through the detection coil 24, and the output of the rectifier circuit 25 becomes a certain voltage (Vs) or more. Then, the comparator 32 detects the output voltage, outputs a prohibition signal (H), and opens the contact of the normally closed switch 34. Therefore, the microphone 11 is disconnected from the circuit, and howling is suppressed from occurring due to the turning around from the speaker 12. By appropriately setting the reference voltage Vs, it is possible to generate the prohibition signal even if the output of the rectifier circuit 25 is insufficient to charge the battery 15.

In the above embodiments, the situation switch 34 connected in series to the output of the microphone 11 is used as the disconnecting means. However, the present invention is not limited to this, and the output of the comparator (prohibition) may be used. The call line itself may be disconnected (operation stopped / power off) based on the signal), and the microphone 11
The sensitivity of may be reduced. When the sensitivity of the microphone 11 is reduced, a mechanism that automatically disconnects the communication circuit when the cordless handset is set in the charger is provided by a mechanism similar to the conventional method. desirable.

Further, in the above-mentioned embodiment, an example in which the present invention is applied to a cordless telephone slave unit is explained. However, the present invention is not limited to this, and the case where the handset of the master unit is also cordless. The present invention can be applied to its base unit, and can also be applied to mobile phones and other cordless communication devices.

[0024]

As described above, in the cordless communication device according to the present invention, when the communication device is set in the battery charger, if the communication device is approached to a certain degree (close to a distance causing howling) before being completely set, An induced electromotive force is generated in the detection coil by electromagnetic induction based on the magnetic flux emitted from the exciting coil. Therefore, by detecting it by the detection means, the cutting means can be operated and at least the output of the voice detection means can be cut off. Therefore, the sound is prevented from flowing from the voice output means to the voice detection means side, and howling can be prevented.

Since the induced electromotive force shares the mechanism for charging the internal battery, the structure is simple and compact. Moreover, it is only necessary to be able to detect that the communication device is approaching the charger. Therefore, even if the induced electromotive force is insufficient to charge both ends of the detection coil, it is possible to determine whether the device is approaching. Since it can be detected, it is possible to accurately detect that a predetermined distance that causes howling is approached. Especially, if a comparator is used as the detecting means, such an effect can be easily obtained by setting the reference voltage appropriately.

Further, since the electromagnetic induction is used when charging the battery, it is not necessary to provide a charging terminal in the charger and the communication device, and there is no exposed portion, so that contact failure due to rust or dust adhesion occurs. The battery can be charged without fail.

[Brief description of drawings]

FIG. 1 is a diagram showing a cordless telephone handset and a charger which are examples of a cordless telephone device according to the present invention.

FIG. 2 is a cutaway sectional view showing a part of a slave unit and a charger of the present embodiment.

FIG. 3 is a perspective view showing an example of a conventional slave unit and a charger.

[Explanation of symbols]

 10 Handset (cordless communication device) 11 Microphone (voice detection means) 12 Speaker (voice output means) 13 Wireless circuit (communication means) 15 Battery 18 Charger 20 Excitation coil 24 Detection coil 25 Rectifier circuit (charging means) 26 Backflow prevention Diode (charging means) 32 Comparator (detection means) 34 Normally closed switch (disconnection means)

Claims (4)

[Claims] 1. A voice detection means, a voice output means, and a wireless means driven by an internal battery, and a detection coil capable of detecting a magnetic flux generated from an excitation coil provided in a charger for charging the internal battery. And a charging means for charging the internal battery based on an induced electromotive force generated in the detection coil by electromagnetic induction, wherein the cordless communication device detects the induced electromotive force to charge the internal battery. A cordless speech communication apparatus comprising: a detection unit that detects that the device has approached a device; and a disconnection unit that disconnects at least the output of the voice detection unit based on the detection result of the detection unit. 2. The cordless communication device according to claim 1, wherein the detection means is a comparator that receives an output voltage of the detection coil as an input. 3. The cordless communication device according to claim 2, wherein a reference voltage of the comparator is set to be lower than a voltage required to charge the internal battery. 4. The disconnection means is at least one of a switch that lowers the sensitivity of the voice detection means or disconnects the output of the voice detection means from another circuit. The cordless communication device according to any one of claims 1.