JPH03159448A - Codeless telephone - Google Patents

Abstract

PURPOSE:To prevent lines from being insignificantly connected by disconnecting the connection of the lines after 30 seconds based on a busy tone signal transmitted from a telephone station and switching a base unit and a handset to a standby state. CONSTITUTION:When the connection of the line comes to insignificantly be connected, the busy tone signal is transmitted from the telephone station after 30 seconds from when the system comes to that state. When the detection signal Sd of the busy tone signal is outputted from a detection circuit 23, and a timer 31 starts. When 30 seconds passes, for example, a micro computer 30 releases the driving of a relay 22 and the contact point 11 is switched off. Consequently, the lines L1 and L2 are released from the base unit 10. Then, a control signal showing termination is transmitted from the base unit 10 to the handset 40 and the handset 40 is switched to a standby mode from a communication mode.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to cordless telephones.

[Summary of the invention]

This invention prevents a cordless telephone from continuing a meaningless line connection by disconnecting the line after a predetermined time when the cordless telephone continues to be in an off-hook state for no reason.

[Conventional technology]

For standard telephones, whether the handset is attached to the main body or
By checking whether there are any calls, you can immediately determine whether the telephone line (office line) is connected or not.

[Problem to be solved by the invention]

However, cordless telephones have a handset (
(Slave unit) is not placed in a specific position. Therefore, with cordless telephones, it is not possible to determine whether the line is connected or not from the status of the handset, so the line connection status cannot be determined from the
It is displayed by ED.

However, since the LED is small, it is easy to overlook it and the line may remain connected for no reason.

If the line is left connected meaninglessly in this way, not only will it be impossible to receive calls to the cordless telephone, but it will also be a problem for the telephone office.

Additionally, while the line is connected, the communication channel between the cordless telephone handset and its base unit remains open via radio waves, which wastes the handset's battery. It will be done. Furthermore, it is a nuisance to other cordless telephones as well, as the communication channel is blocked.

This invention attempts to solve these problems.

[Means to solve the problem]

Now, considering the case where the line connection continues for no reason, there are the following five cases.

■ When dialing is left unattended before completion (when dialing remains off-func). i.e. off-funked, but then,
When you do nothing or stop dialing midway and leave it alone.

■ When you make a call and the other party is busy, so you leave the call as it is.

■ When the other party hangs up during a call, but you leave the call unchanged.

■ When you and the other party leave the call unattended during a call.

■ When you leave the other party unattended while calling.

Then, in the case of Items ■ to ■ of these Items ■ to ■, 30 seconds after the phone is left unattended, an alarm signal called a "busy tone" is sent from the telephone office to the abandoned telephone. .

In other words, when a busy tone signal is sent,
This is the case when the line remains connected for no reason.

This invention focuses on this point and is designed to disconnect the line when a busy tone signal is sent.

[Function] If a busy tone signal is detected while a line is connected, the line is disconnected after a predetermined period of time.

[Example] Figure 1 shows Ite, L. , L, is the line, (1o) is the pace unit of the cordless telephone, and (40) is the handset.

In Pace Unisoto (1o), (11) is a constant contact for a hook switch, (l2) is a diode bridge, and this diode bridge (12) is
This is to prevent the polarity reversal from affecting the subsequent stage when the polarities of the lines L1 and L2 are reversed.

(13) A switch circuit for forming a signal pulse, (14) a communication circuit having a 2-wire/4-wire conversion circuit, etc., (15) a transmitting circuit, (16) ! In the receiving circuit, (l7) is its antenna.

Furthermore, (2l) is a detection circuit for an IJ signal at the time of an incoming call;
(22) is a relay, and the contact of this relay (22) is the contact (11).

(23) is a busy tone signal detection circuit; (24)
) is a DTMF signal decoder, (30) is a microcomputer, and this microcomputer (30) controls the entire operation of the Heas Unit (1). In addition, this microcomputer (30) is equipped with, for example, 30
A second timer (31) is used and raised.

Furthermore, the handset (40) is -i
Since this is the same as the handset in a cordless telephone, a detailed explanation of its structure will be omitted.

When making a call, when the handset (40) is changed from stand-high mode to call mode, a call channel using FM signals (radio waves) is opened between the handset (40) and the base unit (lO) according to a predetermined protocol. . Furthermore, the relay (22) is driven by the microcomputer (3o) and the contact (11) is turned on. Therefore, the handset (40) is connected to the lines L1, L2 through the base unit (10).

Therefore, when you enter the other party's telephone number using the dial keys on the handset (40), the DTMF of that dialed number is
The signal is converted to an upstream FM signal, and this F
The M signal is transmitted from the handset (40) to the base unit (1
0).

Then, in the base unit (lO), the DTMF signal is extracted from the receiving circuit (16), and the DTMF signal is extracted from the receiving circuit (16).
The MF signal is decoded by the decoder (24) and supplied to the microcomputer (30), and the microcomputer (30) turns on and off transistors Q1 and Q2 of the switch circuit (13) to form a dial pulse for the other party's telephone number. This dial pulse passes through the diode bridge (12) and the contact (1l) to the line L. ,L. I can send it to.

Then, when the other party answers the phone, the voice signal is transmitted to line L.
,, is supplied from L2 to the transmitting circuit (15) through the signal line of the contact (11) → bridge (l2) → switch circuit (13) → speech circuit (14), and transmits the FM of the down channel.
This FM signal is converted into a signal and this FM signal is sent to the handset (40).
sent to. Therefore, the other party's voice can be heard from the receiver of the handset (40).

When the user speaks into the handset (40), the voice signal is converted into an uplink FM signal, and this FM signal is transmitted to the base unit (10).

Then, in the base unit (■0), the transmitted audio signal is taken out from the receiving circuit (16), and this audio signal is transferred from the communication circuit (14) to the switch circuit (13).
)→bridge (12)→contact (l1) and is sent to lines L1 and L2 through the signal line.

Therefore, the handset I- (40) can be used to talk to the other party.

When the call ends, the handset (40) is switched from the call mode to the standby mode, and the handset (40) and the pace unit (
10) The communication channel by FM signal is closed. Furthermore, the relay (22) by the microcomputer (30)
The drive of is released and the contact (11) is turned off, so that the lines L, , L2 are released from the base unit (10).

Furthermore, when a call arrives, the ringer signal is transmitted to the detection circuit (21
), and its detection output is supplied to the microcomputer (30). Then, the handset (40) rings according to a predetermined protocol, and in response to this, when the handset (40) changes from standby mode to call mode, the base unit (10) and the handset (
40), a communication channel using FM signals is opened.

Furthermore, the relay (22) is driven by the microcomputer (30) and its contact (11) is placed in an off-hook state.

Therefore, from now on, it will be possible to make a phone call using the hand 71 (40).

On the other hand, if the line continues to be connected for no reason, that is, if the conditions described in ■ to ■ above occur, a busy tone signal will be sent from the central office after 30 seconds from the time the line is connected. It will be sent to you.

Then, this busy tone signal is sent to lines L1 and L2 → contact (11) → bridge (12) → switch circuit (13)
The detection circuit (23) outputs the detection signal Sd of the busy tone signal, and this signal Sd is sent to the microcomputer (30).
).

In the microcomputer (30), when the signal Sd is supplied, a timer (31) is started by this, and when 30 seconds have elapsed, an output indicating this is obtained from the timer (3l), and this timer output Based on microcontroller (3
0), the drive of the relay (22) is released and its contact (11) is turned off. Therefore, the line L,,
L. is released from the base unit (10).

Furthermore, from the base unit (IO), hand cenotaph <4
A control signal indicating a talk is sent to 0), and the hand 7l-
When (40) receives the control signal indicating the end of the call, it switches from the call mode to the standby mode.

Further, the base unit (10) also switches from the call mode to the standby mode after transmitting the control signal indicating the end of the call.

〔Effect of the invention〕

Thus, according to the present invention, when the above states ① to ② occur, the line LI. ．． The connection b't of L2 is cut, and the base unit (10) and hand center (
40) is switched to standby state.

Therefore, according to the present invention, it is possible to prevent the lines L1 and L2 from remaining connected meaninglessly, and it is possible to avoid troubles such as not being able to receive calls to the cordless telephone.

Also, pace unit (10) and handset (40)
Since the communication channel is not left open in between, the battery of the handset (40) is not wasted. Furthermore, the call channel is not blocked for any reason, which is not a nuisance to other cordless telephones.

Furthermore, if you immediately disconnect lines L1 and L2 when a busy tone signal is sent from the central office, even if you make a call and the other party is busy (at this time, a busy tone signal will be sent). ), the caller (the user of the handset (40)) is confused because the caller (the user of the handset (40)) mistakes it as a malfunction. By (3l),
For example, the lines L, L2 are disconnected after 30 seconds, so if a call is made and the other party is busy, the call will not be disconnected immediately and the caller will not be confused.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an example of the present invention. L,,L2 is the line, (10) is Hess Uninote, (11
) is a contact, 14) is a communication circuit, (l5) is a transmission circuit,
(16) is a receiving circuit, (23) is a busy tone signal detection circuit, (30> is a microcomputer, (31) is a timer, and (40) is a hand centrifuge.

Claims (1)

[Claims] A cordless telephone comprising a base unit connected to a line, and a handset to which the base unit is connected through a communication channel during a call, wherein the base unit receives a signal sent through the line. It has a detection circuit that detects a busy tone signal, and when this detection circuit detects the busy tone signal,
A cordless telephone that opens the above line based on the detection output.