JPH0851472A - Charging device for cordless telephone set - Google Patents

Abstract

PURPOSE:To recharge a battery of a slave telephone set to a sufficient degree in a short time by increasing a charging current in the case where the charge of the battery on the side of the slave set becomes not enough by providing the slave set with a means for transmitting data on judgment of the charge of the battery to a master set while providing the side of master set with a charging current switching means and a means for switching and controlling the switching means. CONSTITUTION:If the charge of a battery 24 is less than a prescribed value when a slave set B is set up on a charger 1, data indicating insufficient charging are sent from a microcomputer 26 to the master set A through a transmission data sending circuit 39 or the like. On the master set A side, the data relating to the charging of the battery from the slave set B are detected by a received data detection circuit 37 and a signal indicating insufficient charging is impressed to the microcomputer 26. A high level signal is outputted from a control signal output terminal 36, a transistor 34 is turned on, impedance between a charging terminal 4 and the earth is reduced, and a large current for quick charging is allowed to flow into the battery 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charging device for a cordless telephone.

[0002]

2. Description of the Related Art A conventional charging device for a cordless telephone is shown in FIG.

In FIG. 2, A is a block showing a base unit of a cordless telephone, 1 is a charger integrally provided with the base unit A, and a rectifying / smoothing circuit for rectifying and smoothing a commercial AC power source and converting it to a DC power source. (DC voltage source) 2 and charging terminals 3 and 4 are provided. One charging terminal 3 is connected to the rectifying / smoothing circuit 2,
The other charging terminal 4 is connected to a constant current circuit 5 and an on-hook detection signal generating circuit / charging detection signal generating circuit 6. Reference numeral 7 is a control means for controlling the entire base unit A, for example, a microcomputer. 8 is a constant voltage circuit,
9 is a call path switching circuit for the master / slave unit, a ringer circuit,
Keyboard, handset (microphone and speaker)
The main device section of the base unit A including the general subscriber telephone line section 1
Connected to 0. 11 is a transmitting circuit 12 and a receiving circuit 1
3, a wireless line unit including an antenna 14 and the like. 37 is
The reception data detection circuit 37 is a reception data detection circuit that detects the data transmitted from the child device.
And a reception data input terminal 38 of the microcomputer 7 are connected.

The constant current circuit 5 includes a transistor 15 having a collector connected to the charging terminal 4, and the transistor 15
Resistor 16 connected between the emitter of the transistor and the ground, and diodes 17, 17 connected between the base of the transistor 15 and the ground
And a resistor 41 having one end connected to the base of the transistor 15.

The detection signal generating circuit 6 includes a grounded-emitter transistor 18 having a collector connected to a predetermined terminal of the microcomputer 7, and resistors 19 and 20.

Reference numeral B is a block showing a cordless telephone handset. 21 and 22 are charging terminals provided on the slave unit B side,
A charging battery 24 is connected between one charging terminal 21 and the other charging terminal 22 via a backflow prevention diode 23. First and second voltage detection resistors R1 and R2 are also connected in series between the charging terminals 21 and 22. The connection point 25 of the resistors RI and R2 is a control means for controlling the entire slave B, for example, a microcomputer 26.
Connected to a predetermined input port of. 27 is a transmission circuit 2
8, a wireless circuit unit including a receiving circuit 29, an antenna 30, and the like,
Reference numeral 31 is a device unit including a keyboard, a handset (microphone and speaker), and the like. Reference numeral 39 denotes a transmission data transmission circuit for transmitting data such as data relating to the capacity of the rechargeable battery 24 judged by the microcomputer 26 on the slave unit B side. This transmission data transmission circuit is a data output terminal 40 of the microcomputer 26. And the transmission circuit 28.

In the circuit of FIG. 2, the on-hook detection signal generation circuit 6 also functions as a charge detection signal generation circuit for the battery 24. That is, when the child device B is placed on the charger 1,
While the charging terminals 3 and 21, 4 and 22 are in contact with each other and the commercial power source is energized, the rectifying / smoothing circuit 2, the master unit side charging terminal 3, the slave unit side charging terminal 21, the backflow prevention diode 23, the charging battery 24, The charging current flows through the slave-side charging terminal 22, the master-side charging terminal 4, and the constant current circuit 5, and the charging battery 24 is charged. In the constant current circuit 5 of the parent device A, a voltage drop occurs when a current flows, so the voltage of the charging terminal 4 which was 0 V when the child device B was not placed on the charger 1 becomes high, and the detection signal is output. The voltage rises to turn on the transistor 18 of the generating circuit 6. Therefore, the output of the detection signal generating circuit 6 (collector output of the transistor 18) becomes low level.

The microcomputer 7 of the parent device A detects that the child device B is placed on the charger 1 because the output of the detection signal generating circuit 6 is at a low level, and enters the on-hook state. It is detected that the rechargeable battery 24 is in a charged state, and the telephone line is cut off or the standby mode is entered.

On the side of handset B, the charging current is diode 2
3 and charging battery 24, charging terminals 21, 22
Since a predetermined voltage is generated between them, the voltage is divided by the resistors R1 and R2 forming the on-hook detection signal generation circuit / charging detection signal generation circuit 32, and the divided output level is read by the microcomputer 26, and the slave unit is read. It is detected that B is placed on the charger 1. At the same time, the microcomputer 26 detects that the handset B is in the on-hook state and the charging battery 24 is in the charge state, and shifts the handset B to the standby mode.

[0010]

In the case of FIG. 2, when it is detected that the slave unit B is placed on the charger 1, the rechargeable battery 24
Is charged, and on-hook detection (whether or not the child device B is placed on the charger 1) can be detected on either side of the parent device A and the child device B.

However, in the case of the circuit shown in FIG. 2, the charging current flowing through the rechargeable battery is constant regardless of the capacity of the rechargeable battery 24. There was a problem that the battery was not charged to a sufficient capacity even when it was placed on.

Therefore, when the charging current of the rechargeable battery is controlled by the handset unit and the capacity of the rechargeable battery becomes small,
It is possible to increase the charging current flowing in the rechargeable battery, but in the case of such a cordless telephone, a large capacity circuit element for controlling the charging current is required on the handset side. There is a problem that a large space is required on the machine side, which hinders downsizing of the device.

[0013]

In view of the above points, the present invention provides a master unit connected to a general subscriber telephone line section, provided with a direct current voltage source obtained by rectifying and smoothing a commercial AC power source, and a wireless line. And a slave unit that can communicate with the master unit through a unit, one terminal is connected to the DC voltage source and the other charging terminal is an on-hook detection signal generation circuit on the master unit side. A cordless telephone charging device comprising a connected charger and a charging battery provided on the slave unit side and supplied with a charging current when the slave unit is mounted on the charger, wherein the slave unit side Is provided with determination means for determining the capacity of the rechargeable battery, and transmission means for transmitting the data determined by the determination means to the main unit side, and the main unit side is connected to the rechargeable battery from the charger. Charging current switching means for switching the flowing charging current Characterized in that a control means for controlling switching of the charging current switching means based on the data relating to the capacity of the rechargeable battery transmitted from the slave device side.

Further, when the capacity of the rechargeable battery judged by the judging means on the slave side is not less than the predetermined capacity, the control means on the master side sets the switching means so that a small charging current flows through the rechargeable battery. However, when the capacity of the rechargeable battery judged by the judgment means on the slave side is less than the predetermined capacity, the control means on the master side sets the switching means so that a large charging current flows through the rechargeable battery. It is characterized by having done.

Further, the large charging current is for rapid charging, and the small charging current is for normal charging.

[0016]

According to the above construction, when the capacity of the rechargeable battery of the child device is small, a large current flows through the rechargeable battery, so that the rechargeable battery is charged rapidly.

Since the circuit for controlling the charging current flowing through the charging battery of the slave unit is provided on the master unit side, the slave unit side does not need a large capacity circuit element for controlling the charging current of the charging battery. is there.

[0018]

EXAMPLE An example of the present invention will be described below.

FIG. 1 is a circuit block diagram showing a charging device for a cordless telephone according to the present invention.

In FIG. 1, the same parts as those in FIG. 2 are designated by the same reference numerals as those in FIG. 2 and their description is omitted.

In the circuit of FIG. 1, the resistor 16 on the base A side is
Transistor 3 forming resistor 33 and charging current switching means
A series circuit 35 having a collector-emitter path of 4 is connected in parallel. The base of the transistor 34 is connected to the charging current switching control signal output terminal 36 of the microcomputer 7.

The other structure is the same as that of FIG.

In the embodiment shown in FIG.
6, the capacity of the rechargeable battery 24 is always determined. When the child device B is placed on the charger 1, if the battery capacity of the rechargeable battery 24 is not less than the predetermined capacity, the rechargeable battery 24
The data showing that the capacity of the
Is transmitted to the base unit A via the transmission data transmission circuit 39, the transmission circuit 28, and the antenna 30. At this time, since the L (low) level signal is output from the control signal output terminal 36 of the microcomputer 7 of the parent device A, the transistor 34 is turned off. Therefore, in this case, a current determined by the resistor 16 flows between the charging terminal 5 and the ground, and the charging battery 24
A current for charging normally flows through.

On the other hand, if the capacity of the rechargeable battery 24 is less than the predetermined capacity when the slave unit B is placed on the charger 1, data indicating that the capacity of the rechargeable battery 24 is insufficient is stored in the microcomputer 26. From the transmission data transmission circuit 39 and the transmission circuit 2
8, sent to the base unit A via the antenna 30. At this time, the reception data detection circuit 37 on the side of the master unit A causes the slave unit B to
Data relating to the capacity of the rechargeable battery 24 sent from is detected, and a signal indicating that the capacity of the rechargeable battery 24 is insufficient is applied to the microcomputer 26. As a result, microcomputer 2
An H (high) level signal is output from the control signal output terminal 36 of 6, and the transistor 34 is turned on.
Therefore, in this case, since the resistor 33 and the collector-emitter path of the transistor 34 are connected in parallel with the resistor 16, the impedance between the charging terminal 4 and the ground becomes small, and the current flowing from the charging terminal 4 to the ground, that is, the charging A large current for rapid charging flows through the battery 24.
For example, a current three times as large as that during normal charging flows.

As a method for determining the capacity of the rechargeable battery 24, for example, the cordless handset B is mounted on the charger 1 and the rechargeable battery 2 is charged.
There is a method in which the microcomputer 26 counts the time during which the charging current is flowing through the mobile phone 4, the time during which the slave B is disconnected from the charger 1 and the telephone call is performed, and the capacity of the rechargeable battery 24 is determined based on the result.

[0026]

As described above, according to the present invention, when the capacity of the rechargeable battery of the slave unit is small, a large current flows through the rechargeable battery, so that the rechargeable battery is charged rapidly. Therefore, even when the capacity of the rechargeable battery of the child device becomes small, the rechargeable battery of the child device is quickly charged to a sufficient capacity by mounting the child device on the charger.

Since the circuit for controlling the charging current flowing in the charging battery of the slave unit is provided on the master unit side, the slave unit side does not need a large capacity circuit element for controlling the charging current of the charging battery. is there. Therefore, a large space for storing a large capacity circuit element is not required on the slave side,
Effective for downsizing equipment.

[Brief description of drawings]

FIG. 1 is a block diagram showing a charging device for a cordless telephone according to the present invention.

FIG. 2 is a block diagram showing a conventional charging device for a cordless telephone.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Charger 2 Rectifying / smoothing circuit (DC voltage source) 6 On-hook detection signal generating circuit 7 Microcomputer (control means) 10 General subscriber telephone line section 11, 27 Radio line section 24 Rechargeable battery 26 Microcomputer (determination means) 28 Transmission circuit 34 Transistor (Switching Means) 39 Transmission Data Transmission Circuit

Claims (3)

[Claims] 1. A master unit provided with a DC voltage source obtained by rectifying and smoothing a commercial AC power source and connected to a general subscriber telephone line unit, and a slave unit capable of communicating with the master unit through a wireless line unit. A charger provided integrally with the master unit, one terminal of which is connected to the DC voltage source and the other charging terminal of which is connected to an on-hook detection signal generation circuit of the master unit; and a charger which is provided on the slave unit side. A charging device for a cordless telephone comprising a charging battery to which a charging current is supplied when the slave unit is mounted on the charger, wherein the slave unit has a determining unit for determining the capacity of the charging battery. And a transmission unit for transmitting the data determined by the determination unit to the master unit side, and the master unit side, the charging current switching unit for switching the charging current flowing from the charger to the charging battery, The rechargeable battery sent from the child machine side And a control means for controlling the switching of the charging current switching means based on the data regarding the capacity of the cordless telephone. 2. When the capacity of the rechargeable battery judged by the judging means on the slave side is equal to or larger than a predetermined capacity, the control means on the master side sets the switching means so that a small charging current flows through the rechargeable battery. However, when the capacity of the rechargeable battery determined by the determination means on the slave side is less than the predetermined capacity, the control means on the master side sets the switching means so that a large charging current flows in the rechargeable battery. Claim 1 characterized by the above.
Charging device for the cordless telephone described. 3. The large charging current is for fast charging,
The charging device for a cordless telephone according to claim 1 or 2, wherein the small charging current is for normal charging.