JPH05122305A - Cordless telephone set - Google Patents

Abstract

PURPOSE:To allow a master set to continue talking succeedingly by sending a speakerphone request signal to the master set when a slave set is busy with an external line and a battery is going to be worn out. CONSTITUTION:When a level of a voltage of a secondary battery 36 of a slave set 2 detected by a battery voltage detection circuit 37 reaches a prescribed level or below, its output signal changes from an H level to an L level. When an L level signal is outputted from the battery voltage detection circuit 37 in busy with an external line by the slave set 2, a control circuit 39 of the slave set 2 drives a buzzer 38 for 10sec to inform a worn battery and then sends a hand-free request signal to the master set 1. A main control circuit 25 of the master set 1 receiving the hand-free request signal from the slave set 2 controls a voice path changeover circuit 23 to connect a loudspeaker 12, a microphone 13, a hand-free circuit 14 and a network circuit 10 in this order respectively. Thus, even when the talking by the slave set 2 due to the worn battery is not available, the talking by the master set 1 is attained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cordless telephone system comprising a master unit connected to a telephone line and a slave unit wirelessly connected to the master unit.

[0002]

2. Description of the Related Art In recent years, a cordless telephone device comprising a base unit connected to a telephone line and a handset unit wirelessly connected has become widespread, and such a device is disclosed in Japanese Patent Laid-Open No. 1-314452. There is.

[0003]

By the way, in the above-mentioned slave unit, due to its portability, it is driven by a secondary battery, and if the battery runs out during a call, the call is cut off. In this case, courtesy of the call destination is lost, and it takes time and effort to make a call again and wastes call charges.

[0004]

In the cordless telephone device of the present invention, the slave unit is provided with means for transmitting a speakerphone request signal, and the master unit receives the speakerphone request signal from the slave unit to make a speakerphone call. A means for setting the mode is provided.

[0005]

The present invention is constructed as described above,
When the battery is running out while talking to an outside line by the slave, a speakerphone request signal is transmitted to the master, and thereafter the master can talk.

[0006]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a cordless telephone device according to the present invention, in which (1) is a master unit connected to a telephone line (L),
(2) is a slave unit wirelessly connected to the master unit (1), and has charging terminals (3) and (4). A charging stand (5) has charging terminals (6) and (7) that come into contact with the charging terminals (3) and (4) when the slave unit (2) is placed, and charges the slave unit (2). Is.

FIG. 2 shows a block diagram of the base unit (1), (8) a receiving circuit for receiving a signal from the handset (2), and (9) transmitting a signal to the handset (2). It is a transmission circuit. (10) is a network circuit connected to the telephone line (L) and includes a connection circuit for connecting and disconnecting the telephone line (L). Reference numeral (11) is a handset, and reference numerals (12) and (13) are a loudspeaker and a microphone for hands-free communication. (14) is a hands-free circuit for preventing howling during hands-free, which is a transmission attenuation circuit (15) that attenuates the transmission signal, a reception attenuation circuit (16) that attenuates the reception signal, and a pre-attenuation circuit. A level comparison circuit (17) for comparing the signal levels of the transmission signal and the reception signal and the attenuation amounts of the transmission attenuation circuit (15) and the reception attenuation circuit (16) based on the output of the comparison circuit (17). A damping control circuit (18) for The hands-free circuit (14) is disclosed in, for example, Japanese Patent Laid-Open No. 58-162157.
This is a well-known technique as disclosed in Japanese Patent Laid-Open Publication No. Gazette, and a further description will be omitted here. (19) is a hook detection circuit for detecting on-hook and off-hook of the handset (11), (20) is a key circuit including a numeric keypad (21) and a hands-free key (22), (23) is a reception circuit (8) and transmission Circuit (9), network circuit (1
0), loudspeaker (12) and microphone (1)
3), hands-free circuit (14), handset (1
1) is a voice path switching circuit which is selectively connected under the control of the main control circuit (25), and each circuit is connected in the following combinations.

Handset (11) → network circuit (10) Loudspeaker (12) and microphone (13)
→ Hands-free circuit (14) → Network circuit (1
0) Receiving circuit (8) and transmitting circuit (9) → network circuit (10).

The above-mentioned numbers correspond to the control commands from the main control circuit (25), and the terminals of the circuits not described in the above combinations of connections are open.

Reference numeral (24) is a dial circuit for sending a dial signal to the network circuit (10) under the control of the main control circuit (25), and reference numeral (25) is a control circuit composed of a microprocessor. ) It controls the whole.

FIG. 3 shows a block diagram of the slave unit (2),
(26) is a receiving circuit for receiving a signal from the base unit (1),
(27) is a transmission circuit for transmitting a signal to the master unit (1). (28) is a speaker connected to the amplifier (29),
(30) is a microphone connected to the transmitting circuit (27). (31) is a key circuit including a numeric keypad (32), a call key (33) and an off key (34), and (36) is charged from a charging stand (5) via charging terminals (3) and (4). A secondary battery supplies power to each circuit. (3
7) is a battery voltage detection circuit for detecting the voltage of the secondary battery (36).
The output signal changes to the level. Reference numeral (38) is a buzzer for notifying the dead battery, and reference numeral (39) is a control circuit composed of a microprocessor for controlling the entire slave unit (2).

Next, the operation of the above configuration will be described.

First, the basic operation will be described. When the handset (11) is off-hook, the main control circuit (2
5) controls the voice path switching circuit (23) to connect the handset (11) to the network circuit (10) and the telephone line (L). As a result, a call can be made using the handset (11).

The hands-free key (2) on the base unit (1) side
2) is operated, and when the main control circuit (25) detects this, the main control circuit (25) causes the audio path switching circuit (2).
3) is controlled to connect the loudspeaker (12) and the microphone (13), the hands-free circuit (14), and the network circuit (10) in this order and also to connect the telephone line (L). As a result, a hands-free call can be made on the base unit (1) side.

When the hands-free key (22) is operated again, the main control circuit (25) releases the connection and releases the line, so that the call can be terminated. next,
When the call key (33) of the slave unit (2) is operated and detected by the control circuit (39), the control circuit (38) transmits a line connection request signal. The main control circuit (25) of the base unit (1) which receives the line connection request signal controls the voice path switching circuit (23) to activate the reception circuit (8), the transmission circuit (9) and the network circuit (10). Connect and connect the telephone line (L).

In the call state of the slave unit (2),
When the cut key (34) is operated, the control circuit (39) of the slave unit (2) transmits a cut signal to the master unit (1), and the main control circuit (25) of the master unit (1) that receives the cut signal. ) Disconnects the above connection and releases the line, so that the call can be ended.

4 and 5 show a control circuit (39) for the slave unit (2) when an L level signal is output from the battery voltage detection circuit (37) during a call with the outside line in the slave unit (2). And a flowchart of a program written in the main control circuit (25) of the master unit (1), the operation will be described below based on this.

First, the control circuit (39) of the slave unit (2) drives the buzzer (38) for 10 seconds to notify that the battery is dead (steps S-1 to S-4). Then, after that, a hands-free request signal is transmitted to the master unit (1), and the sleep mode (stored data backup mode) is entered (step S-5).

On the other hand, the main control circuit (25) of the master unit (1) which has received the hands-free request signal from the slave unit (2) controls the voice path switching circuit (23) to make the loudspeaker (1).
2) and microphone (13), hands-free circuit (1
4), each of the network circuits (10) is connected in this order (steps B-1, 2). As a result, even if the mobile device (2) cannot make a call due to battery exhaustion, the call can be made on the base device (1) side. In order to prevent the main control circuit (25) of the master unit (1) from being notified in this state, whether or not the hands-free key (22) has been operated,
Also check if the handset (11) is off-hook.
If the hands-free key (22) is not operated within this time and the handset (11) is not off-hook within this time, the connection is released and the line (L) is released to terminate the call. (Steps B-3 to 6,
10).

If the hands-free key (22) is operated within 5 minutes, the hands-free call is continued, and if the hands-free key (22) is operated again, the call is terminated in the same manner as described above. (Steps B-4, 7,
10).

Similarly, when the handset (11) is taken off-hook, the call by the handset (11) is continued. At this time, the main control circuit (25) controls the voice path switching circuit (23) to connect the handset (11) and the network circuit (10) (step B-
5, 8). Also in this case, the call can be ended by hooking the handset (11) on the hook in the same manner as described above (steps B-9 and 10).

In the above embodiment, the handset-free request signal is automatically transmitted from the handset unit (2) upon detection of the battery voltage drop. However, the handset-free request key is provided in the handset unit (2). Alternatively, the hands-free request signal may be transmitted based on the operation of this key. In this case, after transmitting the hands-free request signal, it is necessary to set the slave unit (2) to the reception standby state.

In the above-mentioned embodiment, the hands-free call is used, but the so-called speakerphone call in which the microphone (13) is inoperative may be used.

[0025]

As described above, the present invention transmits a speakerphone request signal to the master unit when the battery runs out while talking to the outside line with the slave unit, and the master unit thereafter. It is possible to make a call and prevent interruption of the call due to battery exhaustion.

[Brief description of drawings]

FIG. 1 is a block diagram of a cordless telephone device of the present invention.

FIG. 2 is likewise a block diagram of a parent device.

FIG. 3 is likewise a block diagram of a child device.

FIG. 4 is a flowchart of a program of a main part written in the control circuit of the slave unit.

FIG. 5 is a flow chart of a main program written in the control circuit of the parent device.

[Explanation of symbols]

 1 Master unit 2 Slave unit 12 Loudspeaker speaker 25 Main control circuit 36 Secondary battery 37 Battery voltage detection circuit 39 Control circuit

Claims (1)

[Claims] 1. A cordless telephone device comprising a master unit having a transmitter / receiver connected to a telephone line and capable of driving a loudspeaker to make a speakerphone call, and a slave unit wirelessly connected to the master unit. The slave unit is provided with means for transmitting a speakerphone request signal, and the master unit is provided with means for setting a speakerphone call mode by receiving a speakerphone request signal from the slave unit. Cordless telephone device.