JP2001103130A - Interphone system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an interphone system that suppresses the occurrence of a phenomenon that a voice signal from an external communication terminal is reflected in a slave terminal and returns again to the communication terminal in the case of connecting the slave terminal and the communication terminal. SOLUTION: The interphone system is provided with the slave terminal 1 that has a speech means 11 and a call means 13 and with a master terminal 2 that has a speech means 21 and is connected to the slave terminal and the external communication terminal 5 via a communication channel 4. The master terminal is configured such that the master terminal forms a speech path between the speech means of the slave terminal and the speech means of the communication terminal in the transfer mode and has a transmitter side switch means 24 and a receiver side switch means 28 in the speech path to apply switch control to both the switch means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intercom device capable of transferring a call from a slave terminal installed at, for example, the entrance of a dwelling unit to an external communication terminal via a public line, and in particular, to a sound from the communication terminal. The present invention relates to an intercom device that suppresses a signal from being reflected at a slave terminal and returning to a communication terminal again.

[0002]

2. Description of the Related Art Conventionally, a slave terminal equipped with a communication unit comprising a speaker and a microphone is installed at the entrance of a dwelling unit, and a master terminal equipped with a communication unit also comprising a speaker and a microphone is installed in a dwelling unit. An intercom device in which both terminals are connected via a dedicated line is known.

In this intercom apparatus, when a visitor presses a call button of a slave terminal, a calling chime of the master terminal sounds, and in response, a resident responds at the calling section of the master terminal to respond to the call. And a telephone call unit of the master terminal.

[0004] Further, when a call is received from a slave terminal when a resident is out of the office and is absent, the master terminal automatically calls a communication terminal (such as an outgoing telephone or mobile phone) registered in advance, and the slave There has also been proposed an intercom device with a transfer function that connects a terminal and a communication terminal via a public line so that a visitor and a resident can communicate in real time.

[0005]

By the way, when the slave terminal and the communication terminal are connected via a public line, the slave terminal has a small shape, so that the acoustic coupling between the speaker and the microphone is large, and the transmission voice is not transmitted. However, there is a problem in that the wraparound goes from the speaker to the microphone and returns to the communication terminal side. For this reason, the transmission quality determined by the public line cannot be satisfied, and it is difficult for the communication terminal to talk back because the transmitted voice is returned.

The present invention has been made to solve such a conventional problem. When connecting a slave terminal and an external communication terminal via a public line, an audio signal from the communication terminal is used. It is an object of the present invention to provide an intercom apparatus that suppresses a signal from being reflected by a slave terminal and returning to a communication terminal again.

[0007]

According to the present invention, there is provided an intercom apparatus comprising: a slave terminal having a calling means and a calling means; and an external communication terminal connected to the slave terminal having the talking means and via a communication line. A communication terminal between the communication means of the slave terminal and the communication means of the communication terminal in the transfer mode, and a transmission side switch means and a reception side in the communication path. A switch is provided, and both switches are controlled to open and close.

According to this configuration, when transmitting from the communication terminal to the slave terminal, the transmission switch is closed and the reception switch is opened, so that the voice from the communication terminal reflected by the slave terminal is opened. It is possible to suppress the signal from returning to the communication terminal again.

Further, the master terminal of the intercom apparatus of the present invention has a D terminal for detecting a push button signal from the communication terminal.
It has a TMF detecting means, and has a configuration for receiving and transmitting a predetermined push button signal to control the opening and closing of the transmitting switch and the receiving switch.

[0010] With this configuration, by remote control from the communication terminal, when transmitting from the communication terminal to the handset terminal, the transmission side switch means is closed and the reception side switch means is opened, whereby the handset terminal is opened. The audio signal reflected from the communication terminal and returned to the communication terminal can be suppressed.

[0011]

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

FIG. 1 is a block diagram showing a configuration of an intercom apparatus according to an embodiment of the present invention. This device is a child terminal 1 installed at the entrance or gate of a dwelling unit.
And a main unit terminal 2 installed in the dwelling unit are connected via a dedicated line 3. In addition, base unit terminal 2 is connected to communication terminal 5 via public telephone network (PSTN) 4.

The slave terminal 1 is a communication unit 11 comprising a speaker (SP) 11a and a microphone (MC) 11b.
, A two-wire / four-wire conversion unit 12 for connecting the SP 11a and MC 11b to the dedicated line 3, and a call button 13.

The parent machine terminal 2 has a speaker (SP) 21
a, a microphone (MC) 21b, a telephone network interface (I / F) unit 22 connected to the public telephone network 4, and a two-wire four-wire converter connected to the telephone network I / F unit 22. Unit 23 and an audio signal from public telephone network 4 output from two-wire / four-wire conversion unit 23 or MC 21b.
Transmitting side switch circuit 24 for passing the voice signal from
And an amplifier 25 for amplifying the audio signal output from the transmitting side switch circuit 24, and a two-to-four-wire conversion unit 26 for outputting the audio signal amplified by the amplifier 25 to the dedicated line 3.

The base unit terminal 2 is an amplifier 27 for amplifying the audio signal from the MC 11b of the slave unit terminal 1 output from the two-wire / four-wire conversion unit 26, and a receiving side for passing the audio signal amplified by the amplifier 27. A switch circuit 28,
The signal that has passed through the receiving side switch circuit 28 is SP21
a and the two-line / four-line conversion unit 23.

Further, base unit terminal 2 has a transfer button 31 for selecting a transfer mode, an operation detecting unit 32 for detecting operation of call button 13 and operation of transfer button 31 of child unit terminal 1, and transmission A control unit 33 for controlling the entirety of the base unit terminal 2 in addition to the opening / closing control of the side switch circuit 24 and the receiving side switch circuit 28, and a ringing sound under the control of the control unit 33 when the call button 13 is operated. Notification unit 34
When the call button 13 is operated in the transfer mode, an automatic calling unit 35 for automatically dialing the communication terminal 5 under the control of the control unit 33, and a push button (PB) signal from the communication terminal 5 are detected. DTMF (Dial Tone Multi Fr
equency) detection unit 36.

The communication terminal 5 includes a communication unit 51 having a speaker and a microphone, and an operation unit 52 having push buttons and function buttons for inputting a telephone number of a communication partner.

Next, the operation of the present embodiment will be described. First, an operation in the case where the transfer button 31 of the master terminal 2 is set to the non-transfer mode will be described.

In this case, when the visitor presses the call button 13 of the slave terminal 1, the operation detector 32 of the master terminal 2 detects it and notifies the controller 33. Upon receiving this notification, the control unit 33 controls the notification unit 34 to sound a ringing tone.

When the resident responds with the MC 21b in response to the ringing tone, the voice signal Sa passes through the transmitting side switch circuit 24, and passes through the amplifier 25, the 2-wire 4-wire conversion unit 26 and the 2-wire 4-wire conversion unit 12. It is output from the SP 11a of the slave terminal 1.

A part of the audio signal output from the SP 11a wraps around the MC 11b, and the two-wire / four-wire conversion part 12 of the slave terminal 1, the two-wire / four-wire conversion part 26 of the master terminal 2, the amplifier 27, and the receiver switch The signal is output from the SP 21a via the circuit 28. At this time, since the transmitting side switch circuit 24 and the receiving side switch circuit 28 are closed under the control of the control unit 33, bidirectional communication can be performed.

Next, the operation when the transfer button 31 of the main terminal 2 is set to the transfer mode will be described.

First, the visitor sets the call button 1 of the slave terminal 1
When 3 is pressed, the operation detection unit 32 of the master terminal 2 detects this and notifies the control unit 33. Control unit 3 receiving this notification
Reference numeral 3 controls the notification unit 34 to sound a ringing tone.

Further, since the transfer button 31 is set to the transfer mode, the control unit 33 of the base unit terminal 2 controls the automatic calling unit 35 so that the telephone network I / F unit 22 sends the public telephone network 4
A call signal is transmitted to an exchange (not shown) connected to the switch. As a result, when the dial tone is received from the exchange, the automatic calling unit 35 sends out a dial signal indicating the subscriber number of the communication terminal 5 registered in advance from the telephone network I / F unit 22.

If the communication terminal 5 is off-hook in response to the call, a communication path is formed between the communication unit 11 of the slave terminal 1 and the communication unit 51 of the communication terminal 5. When the user of the communication terminal 5 presses a predetermined push button (for example, numeral 4) of the operation unit 52 in response to the call, the PB signal is transmitted to the DT.
It is detected by the MF detector 36.

When the control unit 33 receives notification from the DTMF detection unit 36 that a predetermined PB signal has been detected, the control unit 33 closes the transmission side switch circuit 24 and controls the reception side switch circuit 28.
Is controlled. The transmitting side switch circuit 24 and the receiving side switch circuit 28 are both opened when the transfer mode is set.

In this state, when a voice signal arrives from the communication unit 51 of the communication terminal 5 via the public telephone network 4, the voice signal is transmitted via the telephone network I / F unit 22 and the two-wire / four-wire conversion unit 23. It is input to the talk side switch circuit 24.

The audio signal that has passed through the transmitting side switch circuit 24 is output from the SP 11a via the amplifier 25, the two-wire / four-wire converter 26, the dedicated line 3, and the two-wire / four-wire converter 12 of the slave terminal 1. . Part of the audio signal output from the SP 11a goes around to the MC 11b, and is converted into a two-wire / four-wire conversion unit 1 of the slave terminal 1.
2. 2-wire 4-wire conversion unit 26 and amplifier 27 of master terminal 2
, And is input to the receiving-side switch circuit 28. At this time, since the receiving-side switch circuit 28 is controlled to be open, the audio signal input from the slave terminal 1 is not output to the communication terminal 5 side.

Next, the user of the communication terminal 5 operates the operation unit 52.
When a predetermined push button (for example, numeral 6) is pressed,
The PB signal is detected by the DTMF detector 36. When the control unit 33 receives the notification that the predetermined PB signal has been detected from the DTMF detection unit 36, the control unit 33 controls the opening of the transmission side switch circuit 24 and the control of closing the reception side switch circuit 28.

In this state, when an audio signal arrives from the MC 11b of the slave terminal 1, the two-wire / four-wire conversion unit 1 of the slave terminal 1
2. 2-wire 4-wire conversion unit 26 and amplifier 27 of master terminal 2
, And is input to the receiving-side switch circuit 28.

At this time, since the receiving side switch circuit 28 is closed, the voice signal is transmitted to the public telephone network 4 through the two-wire / four-wire conversion part 23 and the telephone network I / F part 22 and is transmitted to the communication terminal 5. Is output from the communication unit 51. At this time, since the transmission side switch circuit 24 is controlled to be opened, the voice signal input from the communication terminal 5 is not output to the slave terminal 1 side.

[0032]

As described above, according to the present invention, a transmitting side switch circuit and a receiving side switch circuit are provided in a communication path formed between a slave terminal and a communication terminal, and the communication terminal is connected to the slave terminal. At the time of transmission, by closing the transmission-side switch means and opening the reception-side switch means, it is possible to prevent the voice signal from the communication terminal reflected by the slave terminal from returning to the communication terminal again. An intercom device can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an intercom apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 slave unit terminal 2 base unit terminal 3 dedicated line 4 public telephone network 5 communication terminal 11 communication unit 11a speaker 11b microphone 12 2-wire 4-wire conversion unit 13 call button 21 communication unit 21a speaker 21b microphone 22 telephone network I / F unit 23 2-wire 4-wire conversion unit 24 transmission side switch circuit 25, 27 amplifier 28 reception side switch circuit 31 transfer button 32 operation detection unit 33 control unit 34 notification unit 35 automatic calling unit 36 DTMF detection unit 51 communication unit 52 operation unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04M 9/00 H04M 9/00 H 9/08 9/08

Claims (2)

[Claims] 1. A slave terminal having a calling means and a calling means, and a master terminal having a talking means and connected to the slave terminal and connected to an external communication terminal via a communication line. The master terminal forms a communication path between the communication means of the slave terminal and the communication means of the communication terminal in a transfer mode, and includes a transmitting switch and a receiving switch in the communication path; An intercom apparatus having a configuration for opening and closing both switch means. 2. The base station terminal has DTMF detection means for detecting a push button signal from the communication terminal, and receives a predetermined push button signal to open and close the transmission side switch means and the reception side switch means. 2. The intercom apparatus according to claim 1, further comprising a control unit.