JPH0744717B2 - Automatic selection incoming device - Google Patents

Description

The present invention relates to an apparatus for branching a telephone line into a plurality of extensions and forwarding an incoming call from an extension terminal that has once received it to another extension terminal. It is a thing.

(2) Conventional technology and its problems In this type of conventional apparatus, when transferring an incoming call from an extension terminal that receives a call to another extension terminal that is a call target, dial a number for calling the extension terminal that is a call target. And then transfer.

However, this conventional transfer method is often affected by the type and state of the connected line, and the dial pulse for transfer shown in FIG. 1 (a) is transformed as shown in FIG. 1 (b). However, there was a defect that the normal pulse could not be detected and the accurate line transfer could not be performed.

That is, in the conventional transfer method, since the loop monitoring circuit detects the 1-digit dial pulse from the extension terminal in the network connection state as it is, the DC dial pulse depends on the type of line, the line impedance at the time of connection, etc. Signal (DP signal)
The pulse waveform of was disturbed and the normal pulse waveform could not be detected.

(3) Object of the Invention The present invention provides an automatic selection call-receiving device capable of accurately receiving a pulse so as not to be influenced by the type of line and the line impedance at the time of connection and performing error-free transfer. The purpose is to

(4) Structure and operation of the invention To achieve this object, the automatic selection call-receiving device of the present invention is arranged so that when an incoming call from one line of the telephone network arrives at one of a plurality of extension terminals. In order to transfer the call to another extension terminal of the plurality of extension terminals, the selection number of the transfer destination extension terminal is set to a plurality of digits, and a direct current for calling the extension terminal is set to the line. An internal power supply circuit that supplies power separately from the DC current from the loop, a loop creation circuit that creates a DC loop for the line, and the selection of the plurality of digits with the extension terminal that received the call being connected to the line. When the extension terminal sends the first digit of the number, the DC loop for the line is held by the loop creating circuit, and power is supplied to the extension terminal receiving the call from the extension side. Power supply circuit side And a control circuit for controlling the switching so that the second digit and subsequent digits of the selection number can be stably transmitted without being affected by the state of the line. The selection is configured to be made.

The present invention will be described in detail below with reference to the drawings.

FIG. 2 shows a structural example of an apparatus to which the present invention is applied. FIG. 3 is a circuit diagram showing an example of the configuration of the automatic selection call receiving device according to the present invention and a time chart for explaining the operation, and FIG. 4 is a flow chart for explaining the operation.

2 and 3, 1 is a telephone line, 2 to 4 are extensions, 5 and 6 are telephones, 7 is an automatic facsimile, 8 is a protection circuit, 9 to 11 are loop monitoring circuits, and 12 to 14 are extension switching. Relay switch (B), 15 to 17 are switch circuits for sending a calling signal, 18 is a relay switch (A) for incoming calls, 19 is an incoming call detection circuit, 20 is a polarity detection circuit, 21 is a loop creation circuit, 22
Is a ringing signal generating circuit, 23 is a ring back tone sending circuit, 24 is a multi-frequency signal (PB signal) reception detecting circuit, 25 is a calling signal [Calling Tone: 1100 Hz pure tone (single frequency)
(Hereinafter referred to as CNG signal) detection circuit, 26 is a ringing tone on the line side (P
(B signal) sending circuit, 27 is a facsimile network (1300Hz) incoming call detection circuit, 28 is a line call progress tone detection circuit for detecting 400Hz signals of dial tone, visit tone and ringback tone, and 29 to 31 are internal power supply circuits , 32
Is a voice signal detection circuit, and 100 is a control circuit using a microcomputer.

Next, an example of the operation of the device of the present invention will be described with reference to FIGS. 2, 3, and 4. For an incoming call from the telephone line 1, an incoming call signal is sent to the incoming call detection circuit 19 through the incoming call relay switch (A) 18, and the incoming call detection output is the control circuit.
Entered in 100. The call signal generation circuit 22 operates according to an instruction from the control circuit 100, and the call signal transmission switch circuit is preselected and switched to automatically receive an incoming call.
A call signal is sent to the telephone 5 via 15 contacts to be called. When the telephone 5 picks up the handset in response to the call, the line 1 is captured by the route of [L ₁ → 12 → 9 → 5 → 12 → L ₂ ] and the call state is established.

A method for transferring from the telephone 5 to the telephone 6 will be briefly described. For example, when the extension number of the telephone 5 is "5" and the extension number of the telephone 6 is "6", when the telephones 5 to 6 are transferred, the telephone 5 Dial the number of. At this time, a DP signal pulse is generated from the telephone 5, and the loop monitoring circuit 9 detects the pulse as shown in FIG. After the detection of 6 normal pulses, the control circuit 100 calls the telephone 6 to realize the transfer from 5 to 6. In the present invention, the extension number of the telephone is two digits, and the first digit and the second digit have different meanings. Suppose that the extension number of the telephone 5 is "12" and the extension number of the telephone 6 is "13". FIG. 3 (a) shows the waveform when dialing "13" in order to transfer from the telephones 5 to 6. In the case of the present invention, the first digit of FIG. When the loop monitor circuit 9 detects a momentary interruption on the line 1 due to the DP signal pulse of, the CPU 100 receives the input 9 from the loop monitor circuit 9 to the A relay 18
A loop with the net is created at the contact point a ₁ of the loop by the loop creating circuit 21, and the B relay of the loop monitoring circuit 9 (not shown)
The telephone 5 is disconnected from the telephone line 1 by the contacts b ₁ and b ₂ of the above and is switched to the internal power supply side supplied by the internal power supply circuits 29 to 31 [see FIG. 3 (b)]. In order to distinguish the instantaneous interruption signal due to the DP pulse from the noise on the line, the instantaneous interruption detection has a certain time t as shown in FIG. 3 (c). Relays A and B after t hours when it is judged that it is not noise
The respective contacts are switched as shown in FIG. 3 (b).

In the first digit The reason for using is that the operation becomes faster. Also, 1
Digit Even if is affected by the connection status of the line, it is not affected by the line because the instantaneous interruption time is set to operate. Second-digit dial pulse that means the extension number after switching to internal power supply with the first-digit dial pulse Is detected and the extension is transferred. The second digit pulse sent after switching the internal power supply is an accurate pulse that is not affected by the line type and connection status because the station power supply is not used, and there is no error in the dial pulse (DP pulse). It can be sent out and can be reliably transferred.

FIG. 4 is a flow chart showing the general operation of the circuit of FIG. 2, and FIG. 5 is a flow chart showing the transfer operation according to the present invention.

Next, an example of the operation of the automatic selection call-receiving device of the present invention will be described with reference to FIGS.

First, when power is applied to the device and it starts up, the control circuit (CP
U) Each monitoring process (eg CNG signal monitoring,
PB signal monitoring, facsimile network (F network) ringing signal monitoring, line call progress tone monitoring, etc.) are performed (S ₁ ).

When a call signal arrives from the telephone line 1 in such a state, the call output is sent to the call detection circuit 19 via the contact a ₁ of the call relay switch (A) 18, and the call detection output is sent to the control circuit (CPU). ) Entered in 100 (S ₂ ). Then, the call signal generation circuit 22 operates under the control of the control circuit (CPU) 100 to generate an original extension call signal, and the call signal transmission switch circuit 15 is preselected and switched to automatically accept an incoming call. The extension call signal is sent to the telephone set 5 via the contact point of to call.

When the telephone 5 raises the handset for a call, [L ₁ →
The line is captured by the route of 12 → 9 → 5 → 12 → L ₂ ], and the telephone line 1 and the telephone 5 are connected (S ₃ ).

When the line is captured, the information is transmitted from the loop monitoring circuit 9 to the control circuit (CPU) 100, and the control switches the incoming relay switch (A) 18 (capacitor).
C ₀ side), thus terminating the detection output of the incoming detection circuit 19 is stopped. At the same time, the ringing signal generation circuit 22 also becomes inoperative and the transmission of the extension ringing signal is stopped.

On the other hand, each detection circuit under the control of the control circuit (CPU) 100, for example, line call progress tone (400Hz) detection circuit 2
8, the PB signal reception detection circuit 24, the CNG signal detection circuit 25, the F (facsimile) network incoming detection circuit 27, etc. are activated (S ₄ ).

It should be noted that the detection status of each detection circuit is constantly checked and classified and detected as follows according to each input signal, and the corresponding functional operation is performed (S ₅ ).

PB signal detection When a PB signal is detected, it is detected as an extension telephone number, the corresponding extension telephone (for example, 6) is called, and the telephone line 1 and the extension telephone (for example, 6) are connected by a response. (S _6-1 , S _6-2 , S _6-3 , A).

F network incoming detection (1300Hz detection) When a 1300Hz signal is detected, a facsimile (FA
X) Calls a facsimile (FAX) terminal device (for example, 7) by judging that it is a call from the network, and responds by telephone line 1 and FA
X (for example, 7) is connected (S _7-1 , S _7-2 , S _7-3 ,
A).

If the line call pro Glenstone detection (400 Hz detection) 400 Hz signal is detected, detects as Bijiton, and open the telephone line 1 (S _8, C).

CNG signal detection (1100Hz pure tone detection) When a 1100Hz pure tone signal is detected, it is judged as a CNG signal and the FAX terminal device (for example, 7) is called, and the telephone line 1 and the fax (for example, 7) are connected in response. Set to the state (S _9-1 , S _9-2 , S _9-3 , A).

Other signal detection (voice signal detection) When another signal not included in is detected, it is regarded as a real voice, a predetermined specific telephone (not shown) is called, and the telephone line 1 is identified by a response. Connect to the telephone of (S _10-1 , S _10-2 , S _10-3 , A).

Next, a method for transferring the call to the telephone 6 when the telephone 5 is connected to the telephone line 1 and the telephone call is possible (S ₁₁ ) will be described. The operation flow is shown in FIG.

When transferring from the telephone 5 to the telephone 6, the telephone 5 dials a two-digit extension number. That is, first, of the extension numbers "13" of the telephone 6, the operation of transmitting "1" is performed.
At this time it is detected whether the line interruption (S _12), third
Figure (a) a short break in the break pulse is generated by dial operation as shown in is detected, then the "1" in the first digit of the dialed number is detected (S _13), A in the loop forming circuit 21 A relay (not shown) operates and its contact a ₁
Figure 3 (b) switches to the state shown in the figure (S _14), at the same time B relay loop creation circuit 21 (not shown) becomes inoperative, the contact b _1, b ₂ a third diagram ( After switching to the state shown in (b) (S ₁₅ ), the telephone 5 sets the internal power feeding circuit 29.
It is connected to and receives the power supply from its own direct current, not the station power supply.

The telephone 5 which has been supplied with power from the self-storing power supply dials the second digit extension "3". At this time, it is detected whether or not there is a momentary disconnection of the line (S ₁₆ ), which is shown in FIG. When a break pulse occurs within the line, a momentary disconnection is detected, and the extension number is checked by the control circuit 100 (S ₁₇ ).
3 "call the extension telephone 6 corresponding (S _18). When the extension telephone 6 which is the called terminal responds (S ₁₉ ), the station line and the telephone 6 which is the called terminal are brought on-line (S ₂₀ ), and the line communication state is established (B).

(5) Effects of the Invention As described above, according to the present invention, the selection number for extension transfer is set to two digits or more, and from the second digit onward, power is fed from the internal power feeding circuit to perform stable transmission without affecting the state of the line. With such a configuration, there is an advantage that it is not affected by the type of the line and the connection state, and that it is possible to easily and accurately perform the transfer in the busy state.

[Brief description of drawings]

1 (a) and 1 (b) are waveform diagrams showing a normal DP pulse waveform and a DP pulse waveform disturbed by the type of line and the connection state,
FIG. 2 is a block dialgram showing a device configuration to which the present invention is applied, and FIG. 3 (a) is a diagram when an extension number has two digits.
DP pulse waveform diagram, FIG. 3 (b) is a circuit diagram showing the outline of the internal power supply switching system used in the present invention, and FIG. 3 (c) is a time chart showing the switching timing used in the present invention. 4 and 5 are flowcharts for explaining an operation example of the device of the present invention. 1 ... telephone line, 2,3,4 ... extension, 5,6 ... telephone, 7 ...
… Automatic facsimile, 8 …… Protection circuit, 9,10,11 …… Loop monitoring circuit, 12,13,14 …… External switch relay switch (B), 15,16,17 …… For calling signal transmission Switch circuit, 18 …… Relay switch (A) for incoming call, 19 …… Incoming call detection circuit, 20 …… Polarity detection circuit, 21 …… Loop creation circuit, 22 …… Call signal generation circuit, 23 …… Ringback tone Sending circuit, 24 ... Multi-frequency signal (PB signal) reception detection circuit, 25 ... CNG signal detection circuit, 26 ... PB signal sending circuit, 2
7 …… Facsimile (F) network incoming detection circuit, 28 …… Line call progress tone detection circuit, 29,30,31 …… Internal power supply circuit, 32 …… Voice signal detection circuit, 100 …… Control circuit (C
PU).

Claims (1)

[Claims] 1. When an incoming call from one line of a telephone network arrives at one of a plurality of extension terminals, the incoming call is transferred to another extension terminal of the plurality of extension terminals. In addition, the selection number of the extension terminal of the transfer destination is set to a plurality of digits, an internal power supply circuit for supplying a DC current for calling the extension terminal separately from the DC current from the line, and a DC loop for the line. A loop creating circuit for creating a loop, and a direct current for the line when the first digit of the plural-digit selection number is transmitted from the extension terminal in a state where the extension terminal receiving the incoming call is connected to the line. With the loop held by the loop creating circuit, the power supply to the extension terminal receiving the incoming call is controlled to be switched from the line side to the extension power supply circuit side, and the second digit and subsequent digits of the selection number are set to the above-mentioned. Not affected by line status The automatic selection call receiving device is characterized in that it is provided with a control circuit capable of stable transmission and that the extension terminal as the transfer destination is accurately selected by the selection number of a plurality of digits.