JPH0541730A - Cordless telephone set - Google Patents

Abstract

PURPOSE:To prevent tapping of a slave machine by giving an alarm at the time of detecting that a master machine cannot obtain the response from the slave machine because of takingaway of the slave machine to the outside of the service area of the master machine. CONSTITUTION:When detecting coming of a call period, a master machine 1 transmits a position confirmation signal. A slave machine receives this signal to transmit a response signal corresponding to the position confirmation signal. The master machine 1 starts a timer after transmission of the position confirmation signal and discriminates whether the timer expires at the time of reception of the response signal from the slave machine or not; and if it expires, an alarm 10 indicating that the position confirmation signal is not received is generated. Thus, the abnormality of the slave machine is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cordless telephone in which a master unit and a slave unit are connected by a wireless line.

[0002]

2. Description of the Related Art Conventionally, pink telephones have been provided for making pay calls, but in recent years, cordless public telephones having a handset wirelessly connected to the pink telephone body have been provided. By installing such a device in a shop such as a restaurant, it becomes possible to provide a pay call service to visitors.

When such a device is used, the main body is installed in a corner of the store, the owner uses a specific slave unit, and the other slave units are placed on the table, so that the visitor can talk without standing up. can do. Then, the call charge of the handset is displayed on the display of the main body or printed on the printer.

[0004]

However, such a conventional device is wirelessly connected to the master unit, and unlike the conventional telephone, which is physically connected by a cord, is portable. On the other hand, there was a problem that it was easy to take out and there was a high possibility that it could be taken away.

The present invention has been made in view of such a situation, and an object thereof is to provide an apparatus devised so as not to be taken away.

[0006]

In order to solve such a problem, the present invention provides a slave unit that returns a response signal in response to a periodic call from the master unit, and a response signal from the slave unit. It is composed of a base unit that issues an alarm when it is not present.

[0007]

[Operation] The base unit periodically calls the handset unit,
Each time the child machine responds to this, it sends back a response signal. When the child device is taken away and out of the communication area of the parent device, the parent device cannot obtain a response from the child device, so the parent device detects that there is no response from the child device and issues an alarm.

[0008]

1 is a block diagram showing the configuration of an embodiment of the present invention. In order to prevent the slave unit from being taken out, the master unit 1 periodically sends a call signal to the slave unit, and the slave unit responds to this. Then, if there is no response from the child device within a certain time, the parent device generates a signal for warning the abnormality. The main | base station 1 forms a loop with a station line, and is connected to the station line via the loop control and the billing signal detection part 3 which detects the billing signal sent from the station line. When an incoming call arrives, the loop control / billing signal detection unit 3 detects the incoming call, and the detection result is recognized by the control unit 7.
Is transmitted to the slave units 2 to N wirelessly via.

In the slave unit, the control unit 14 detects the signal received by the wireless unit 12, and the buzzer 17 notifies the incoming call. In this case, normally, only the specific slave unit owned by the owner receives the call, and the other slave units do not ring the buzzer 17. Here, when the owner goes off-hook, the handset 13 of the handset 2 can talk. In this case, the master unit 1 transmits a voice signal through the loop control / billing signal detection unit 3, the call circuit 4, the branch circuit 5, and the wireless unit 11. In addition, the signal via the branch circuit 5 is also supplied to the handset 6 so that a call from the master unit can be performed if necessary.

On the other hand, when the slave unit makes a call, the information is transmitted to the master unit 1 and received by the wireless unit 11, and the control unit 7
The call control process is performed by the loop control / billing signal detection unit 3, the telephone line is connected via the loop control / billing signal detection unit 3, the call becomes possible, and the billing signal transmitted via the station line Is detected by the control unit 7, recognized by the control unit 7, processed by the charge processing unit 8, and displayed on the display unit 9. The charge information at this time is transmitted via the control unit 7 and the wireless unit 11 to the slave unit 2 which is the specific slave unit owned by the owner. Then, the charge information detected by the wireless unit of the handset 2 is recognized by the control unit 14 and displayed on the display unit 15, so that the owner can know the call charge of the customer by looking at the display.

FIG. 2 is a flow chart for explaining the operation of detecting the carry-out of the slave unit. When the master unit detects that the calling cycle has come (step 100), it transmits a position confirmation signal (step 101). This signal is received by the slave unit (step 110), and the slave unit transmits a response signal corresponding to this position confirmation signal (step 111). This response signal has a difference in the return time and the frequency thereof so as not to collide with each other when there are a plurality of cordless handsets. Then, the master unit can detect from which slave unit the return signal has been sent.

The master station 1 starts a timer after transmitting the position confirmation signal in step 101 (step 102). When the response signal from the child device is received (step 103),
It is judged whether or not the timer is up (step 104). If the time is up, the position confirmation signal has not arrived, so an alarm is issued (step 105).

This allows the master unit to know that the slave unit is abnormal. In this case, for example, if a radio wave is emitted from the slave unit for a time sufficiently longer than the calling cycle of the master unit, for example, every hour, it is not the device's failure but the theft that the return signal is not returned during that time. Different judgment is also possible.

In the above embodiment, the master unit warns that the slave unit has been stolen. However, when the slave unit cannot periodically receive the inquiry signal, the slave unit may generate an alarm. .. This also gives a warning to anyone trying to bring it out. Further, although the above embodiment has been described with respect to a public telephone, this is not limited to a public telephone.

[0015]

As described above, according to the present invention, since the master unit periodically sends the interrogation signal to the slave unit and the slave unit responds to the signal, there is no response from the slave unit. In this case, the parent device has the effect of determining that the child device has been stolen and issuing a warning to notify the child device.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing an operation between a child device and a parent device.

[Explanation of symbols]

 1 parent unit 2 slave unit 3 loop control / billing signal detection unit 4 call circuit 5 branch circuit 6 handset 7 control unit 8 fee processing unit 9 display unit 10 alarm unit 11 wireless unit 12 wireless unit 13 handset 14 control unit 15 display Part 16 Key matrix 17 Buzzer 18 Card slot

Claims (1)

[Claims] 1. A cordless telephone having a plurality of cordless handsets that are wirelessly connected to the parent unit, and a cordless telephone that returns a response signal in response to a periodic call from the parent unit, and a response signal from the cordless handset. A cordless telephone, which is composed of a base unit that issues an alarm when there is no return.