JPH03101590A - Telephone exchange - Google Patents

Abstract

PURPOSE:To prevent malfunction due to a pushbutton tone from a communication opposite party by providing a speech direction detection means detecting a speech direction of a voice signal line to a dial signal reception circuit connected to the voice signal line formed between a line wire and a telephone set in the case of line wire dialing. CONSTITUTION:A PB receiver 12 is provided with 2/4-wire conversion circuits 211, 212 dividing a voice signal on a voice signal line depending on the direction of speech and a comparator circuit 22 comparing level of voice signals divided by the 2/4-wire conversion circuits 211, 212 depending on each speech direction and through amplifiers 191, 192. The PB receiver 12 detects the direction of speech (from external line l1 to telephone set or vice versa) by using the comparator circuit 22 so as to compare the levels of the voice signals on the lines divided in the speech direction by the 2/4-wire conversion circuits 211, 212 respectively and whether or not an output of a DTMF receiver 20 is regarded to be valid is judged depending on the output of the comparator circuit 22 by a control circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention relates to a telephone exchange device that switches and forms communication paths between external lines and internal lines, or between internal lines, and enables external and internal phone calls using commercially available telephones. It is.

[Conventional technology] The system configuration of this type of telephone exchange equipment is shown in FIG.

This telephone exchange equipment is connected to a telephone exchange fiA connected to a telephone office E via an external line L via a disconnector G and a protector H, and an internal telephone exchange fiA. and a plurality of notifications (22) B, each of which is connected by one control line and to which a commercially available telephone C is detachably connected, and the above-mentioned telephone exchange f
External line 1 with iA. By switching and forming a communication path between e2 and extension #X12, telephone C connected to notification unit B can be used to make external and internal calls. In addition, this telephone exchange equipment is a telephone line! , the doorphone D is connected to the telephone exchange A, and the telephone C can also be used to make doorphone calls.

Each notification unit) B is equipped with a monocular jack M.
C can be attached and detached to follow. *This notification unit) B is the control line l.

A speaker SP for reproducing notification signals such as an extension ring tone or a doorbell ring signal sent through the control 1181 and a display signal, which is a voltage signal sent through this control 1181s, are used to distinguish between the speaker Alternatively, it is provided with light-emitting displays @La and Lb for indicating an outside line call, etc., and these speaker SP and light-emitting display La5Lb are designed to perform notification and display operations. Note that the volume of the speaker SP can be adjusted using a volume setting switch "vs-c".

[Problem to be Solved by the Invention 1] In this telephone exchange device, when dialing to make an outside call using a button tone from telephone C, telephone C is connected as shown in Fig. 4. Ext. e2 #! The dial signal input from telephone C is received by the PB receiver 12 via the cross-point switch 10, and the control circuit 11 temporarily stores the data decoded by the PB receiver 12. If the number of digits in the signal is 2 or more, drive the PB Guiyara 7 and convert the dial signal to an outside line! , is configured to be sent to. In addition, at this time, telephone MC.

Extension e2, crosspoint switch 10,)? nce T3
, and the outside line 11 are formed, so that the telephone C can hear the voice signal during dialing through this voice signal line. In addition, the above P
The B receiver 12 is configured to receive dial signals as commands such as hold on this audio signal line.

As shown in FIG. 5, the PB receiver 12 is composed of an amplifier 19 that amplifies the signal on the audio signal line, and a DTMF receiver 20 that decodes the button tone into digital data.

However, if a PB tone is input from the other party during this outside line call, the PB receiver 12 inputs the PB tone of the other party.
)-n and P as a command input from telephone C.
B) - cannot be identified as
B) - There was a risk of malfunction due to -.

The present invention has been made in view of the above-mentioned problem [alpha], and its object is to provide a telephone exchange device that does not cause malfunctions when a PB)-phone is received from the other party.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a dial signal receiving circuit connected to a voice signal line formed between an outside line and a telephone set when dialing an outside line. , a communication direction detection means for detecting the communication direction of the audio signal line is provided.

[Function] As described above, the present invention provides a call direction detecting means for detecting the call direction on the voice signal line in the dial signal receiving circuit, thereby detecting the pushbutton tone as a command from the telephone and the call direction from the outside line. The push button tones can be distinguished to prevent malfunctions caused by push button tones from the other party.

[Example 1 An embodiment of the present invention is shown in FIGS. 1 and 2. FIG.

First, the circuit configuration and operation of telephone exchange A to which the present invention is applied will be explained. However, this telephone exchange A
is the same as the conventional one.

Telephone exchange If! IA is connected to telephone C as shown in FIG.
For each extension 12 to which a relay contact r, to r1.7 is connected, a dial pulse (DP) detection circuit 2. ~23 and talking current supply circuit 4. ~4. It further includes an incoming call detection circuit 5, a DC connection circuit 3, a DP generation circuit 6 for making an outside line call with a dial pulse, a button (PB) guiyate 7 for making an outside call call with a button tone, and detecting an outside line dial tone. an outside line dial tone detection circuit 8, a holding tone sending circuit 9 which sends out a holding tone, a cross point switch 10 which sets a call route, a PB receiver 12-13 which receives a button signal, a diode double 7 DB,... G.
-G5, and a control circuit 11 comprised of a CPU that performs control information signal transmission control and signal determination processing for each of the above-mentioned circuits and circuits (1) to be described later.

In addition, in this telephone exchange A, telephone C can be used to make calls to two door phones D,
Therefore, the door phone call detection circuit 14 detects a call from the door phone D. ．． 14□ and a doorphone call circuit 15. Furthermore, this telephone exchange W1A can also be connected to a security device and an emergency push button, and when a security signal is input or an emergency push button is pressed, a notification that each telephone C is connected is sent. In order to emit a notification sound from the unit B, a security signal detection circuit 16, a sound generation circuit 17 that generates various notification sounds, and amplifiers AMP and -AMP are provided.

In addition, a display control circuit 18 is provided in order to display the outside call and extension call status on the notification unit B.

The operation of this telephone exchange device will be explained. This telephone exchange fi
When the power is turned on and the system starts in A,
First, the control circuit 11 consisting of a one-chip microcomputer performs initial settings, then enters a standby state, determines off-hook, further determines whether an outside line is received and processes the outside line, determines whether there is a doorphone call, and processes the doorphone call. ,
Performs processes such as determining whether there is an extension call, processing the extension call, and processing the outside call.

Now, when the handset of the telephone C connected to one of the notification terminals B is raised, the hook/DP detection circuit 2 detects off-hook and outputs a detection signal to the control circuit 11. In the above state, the relay contacts rl to r3 are switched to the cross point switch 10 side. At this time, the control circuit 11 turns on a predetermined switch of the crosspoint switch 10 and sends out a pseudo-transmission signal of 400 Hz through the notification unit (B) heterospoint switch 10 and the extension 12 through the D/G3. At the same time, the control circuit 11 controls the display control circuit 18 to display a light-emitting display section L for indicating that an outside line is busy in each notification unit)B.
A voltage signal is output to light up the light emitting display section La. At this time, the light-emitting display section Lb for indicating that the extension line is busy is controlled to be turned off.

This transmission continues until the dial signal is input, and when the first dial signal is detected by the 7tsuku/DP detection circuit 2,
The control circuit 11 stops outputting the pseudo call signal and stores the dial data in the built-in buffer memory. Then activate the built-in 3 second timer. If a second dial signal is detected while this timer is operating, it is determined that an outside line call has been made.

If the second dial signal is not input within these 3 seconds, it is determined that the call is an extension call, and the extension call processing is performed.

Now, in the case of an outside line call, data of dial signals that are subsequently input to the buffer memory are sequentially stored, and a signal for operating the DC connection circuit 3 is output. The line is closed by this DC connection circuit 3, the outside line dial tone is detected by the outside line dial tone detection circuit 8, and the detection signal is sent to the control circuit 11.
When the dial data is input to the buffer memory, the control circuit 11 sequentially reads out the dial data stored in the buffer memory starting from the first dial data, operates the dial pulse generating circuit 6, and sequentially sends dial signals to the outside #i t' +. At the same time, the data of subsequent dial signals input from the telephone fic is stored in the buffer 7 memory. This is how you get an outside line! , and simultaneously stores the dial data from the telephone fiB in the buffer memory. When the dial data stored in the buffer memory is exhausted and a certain period of time has elapsed, the next call will proceed to an outside line. Please note that if the dial signal is
1. When transmitting data to , the line connection is interrupted. Thereafter, an external call is made via the coupling transformer T I , the crosspoint switch 10 and the extension line 12 .

Next, the operation when calling an extension will be explained. First, after the first dial signal is input from telephone C connected to notification unit B and a pseudo call signal is output, if the next dial signal is not input within 3 seconds, the input dial data will be Determining that it is an extension number, the control circuit 11 turns off a predetermined switch of the cross-point switch 1o that has been turned on from off-hook, and connects the outside line! , and turn on another predetermined switch to set a call path to internal #t (12). Then, turn off the light-emitting display section La of each notification unit B that had been lit since off-hook, and at the same time The display control circuit 18 outputs a voltage signal that lights up the light-emitting display section Lb indicating that the light-emitting display section Lb is busy.
lights up. Further, the control circuit 11 controls the sound generation circuit 17 to output an alarm signal for calling an extension. This notification signal is superimposed and sent out to the control line p3 of the notification terminal B on the calling side through another switch of the crosspoint switch 10. Notification unit B sent via control #ie3 emits an extension ringing tone from speaker SP.

By this ringing, the telephone 1 connected to this notification unit) B
When fiC's handset is taken away, hook D
The P detection circuit 2 detects this off state and the control circuit 11
sends a detection signal to. Based on this OFF switch, the control circuit 11 stops the generation of the audio signal, and also turns on the other switches of the cross point switch 10, to notify #i 12 of #2)B that made the call. The notification unit on the called side is connected to the extension 12 of B to establish a conversation state.

After that, an extension call will be made.

Below, outside #! I will explain incoming calls. First, outside*
When an incoming call signal is input from the e+, the incoming call detection circuit 5 detects this incoming call signal and sends the incoming call detection signal to the control circuit 11.
Output to. When the control circuit 11 receives this incoming call detection signal, it switches the relay contact r to the outside side. Therefore, each notification 22) telephone 8 IC connected to B
is connected to the outside line 11 through the extension 12, and the built-in bell of each telephone C rings. When the handset of telephone C connected to a certain notification unit (H) is raised due to this ringing, this off-hook state is
It is detected by the detection circuit 2, and the control circuit 1 is detected by this detection output.
1 turns on the DC connection circuit 3, switches the relay contact ``to the ON position of the crosspoint switch 1, and at the same time switches the crosspoint switch 10 to connect the outside line 1. and the extension line of the notification unit (B) connected to the off-hook telephone C. 12 to enable outside calls.

Now, if you want to make an internal call while making an external call, or
If you want to make a doorbell call, you can put it on hold. In this case, a dial signal corresponding to hold is input from telephone C that is in use for an outside line call, and control circuit 11 reads this dial data and determines that the call is on hold, and calls extension t! 2
A hold process is performed to cancel the communication path between the terminal and external IllAc+. Then, the held music sending circuit 9 is operated to send the held music melody signal to the external line e via the coupling transformer T, and the cross point switch 10 is switched to the amplifier A.
It is sent to each control line I through M P + to A M P 3.

Further, under the control of the control circuit 11, the display control circuit 18 sends a voltage signal for simultaneously lighting up the light emitting display sections La and Lb to each notification unit B via the control #i t' 3. , lights up L b. In other words, there is an outside line due to the hold music melody signal! , notifies the other party's phone C that the call is on hold, and at the same time, connects each phone C and emits a hold melody tone from the speaker SP of B to notify the user that the call is on hold. , At the same time, the 5α lights of the light emitting display sections La and Lb indicate that the process is on hold. Here, if you wish to make an extension call after the call is on hold, input the dial signal # for the call from the telephone @C, and the extension call becomes possible according to the above-mentioned extension processing operation. Also, if you make a doorbell call, do you want to use the dial signal for the doorbell call? Input from jIC. Note that this doorphone call processing will be described later.

After the hold, when the telephone C goes on-hook, the extension call etc. is terminated, and the control circuit 11 shifts to the calling operation.
When the telephone 11'lc is taken off-hook, the control circuit 11 stops the operation of the hold tone generating section 9, and controls each section to return to the original outside line call state, making it possible to make an outside line call. Then, when the call after the hold is released and the telephone 8IC is turned on-hook again, the DC connection by the DC connection section 3 is released under the control of the control circuit 11, and the outside line call is ended.

Next, a case where there is a doorbell call will be explained. When making a call from door phone D, a push button provided on door phone D is pressed. When this push button is pressed, the door intercom call detection circuit 14 outputs a signal to the control circuit 11 indicating that there has been an impedance change. The control circuit 11 determines that the call is from the door phone D based on the output, operates the sound generation circuit 17, and switches the crosspoint switch 10 to a predetermined value (9) to send a ringing tone to each notification unit (B). N
A ringtone is emitted from the speaker SP of B.

Then, when a householder who hears the ring tone picks up the handset of one of the telephones C, a signal indicating that the handset has been off-hook is sent from the 7tsuku/DP detection circuit 2 of the notification unit B to which the handset has been off-hook to the control circuit. 1
1, and the control circuit 11 connects the crosspoint switch 1
0 to connect the telephone C whose handset is turned off 77 to the door intercom circuit 15, and turn on the switch element S provided between the door intercom D and the door intercom circuit 15 to enable door intercom communication. do.

The features of this embodiment will be explained below. In this embodiment, the PB receiver 12 includes a 2@-4 line conversion circuit 21, . 21□ and this 2#i-4 line conversion circuit 2
1. 21□ separates the amplifier for each direction of communication 19. ．． 1
Comparison circuit 22 that compares the level of the audio signal passed through 9□
This is provided.

Note that the DTMF receiver 20 has seven amplifiers 19, .
The outputs of 19□ are respectively decoded into digital hoods, and the DTMF renderers 20 and 1 comparator circuit 2
The respective outputs of 2 are input to the control circuit 11. In other words, in this PB receiver 12, each of the 2 wires -4
By comparing the levels of the audio signals on the lines separated by the line conversion circuits 211° and 21□ for each call direction, the comparison circuit 22 can detect the call direction (from the outside line l to the telephone C1 or from the telephone C to the outside line tU). Therefore, the control circuit 11 can determine whether the output of the DTMF receiver 20 is considered valid based on the output of the comparison circuit 22, and it is possible to prevent malfunctions caused by the PB)-tone input by the other party, as in the conventional case.

The above 2@-4 wire conversion circuit 21. , 2L concrete circuit #4
2, which consists of two differential amplifier circuits 23, . 23.
Each differential amplifier circuit 23023. By inputting the outputs of the other differential amplifier circuits 23, .
23□ is configured to prevent the call voice from returning to the input side.

Specifically, each amplifier circuit 23+t23z has the same configuration, including an operational amplifier OP, and a capacitor CI.

It consists of C2 and resistors R and -R.

[Effects of the Invention] As described above, the present invention is provided with a call direction detecting means for detecting the call direction in the dial signal receiving circuit, so that the push button tone as a command from the telephone and the push button from the outside line are It is possible to distinguish between ``to'' and ``to'', which prevents malfunctions caused by the button tone from the other party.

[Brief explanation of drawings]

Fig. 1 is a circuit diagram of a main part of an embodiment of the present invention, Fig. 2 is a specific circuit diagram of a further main part of the same as above, Fig. 3 is a system configuration diagram of a telephone exchange equipment, and Fig. 4 is a telephone of the same as above. switchboard circuit diagram,
FIG. 5 is a circuit diagram of a conventional example. A is a telephone exchange, C is a telephone, E is a telephone office, 12 is P
B receivers 20 are DTMF receivers 21, . 21□
is a 2-wire to 4-wire conversion circuit, 22 is a comparison circuit, 11 is an outside line,
12 is an extension.

Claims (1)

[Claims] (1) A telephone exchange connected to a telephone office via an outside line;
It consists of commercially available telephones each connected to this telephone exchange by an extension line, and the telephone exchange switches and forms communication paths between outside lines and extensions, or between extensions, so that outside calls and internal calls can be made using the above telephone, and outside calls can be made. When dialing, the extension line to which the telephone is connected is disconnected from the outside line, the dial signal from the telephone is received by the control circuit of the telephone exchange, and under the control of this control circuit, the dial signal sending circuit outputs the dial signal. In the telephone exchange equipment that sends out to the outside line,
The dial signal receiving circuit connected to the voice signal line formed between the outside line and the telephone when dialing the outside line is provided with a call direction detection means for detecting the call direction of the voice signal line. Telephone switching equipment.