JPS6393261A - Facsimile connection system for private branch telephone exchange - Google Patents

Abstract

PURPOSE:To store a facsimile in a private branch telephone exchange without increasing the number of extension circuits by preventing a central office line from being acquired by the central office line call transmission from an extension in accordance with central office line busy information due to a monitor means if the facsimile is connected to this central office line and is busy. CONSTITUTION:A DC loop passing a facsimile FAX to a central office line CO is formed during the communication between the facsimile FAX and the central office line CO. A central office line monitor circuit RC detects the DC loop current and outputs the detection signal to a common controller CC through a line l2. The common controller CC does not acquire this central office line CO even if the central office line call is transmitted from an extension telephone set EXT. Thus, the facsimile is stored in the private branch telephone exchange without increasing the number of extension circuits.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a connection system for accommodating a 7-aximu IJ to a private telephone exchange.

[Conventional technology]

When accommodating a facsimile (hereinafter referred to as fax) in a private telephone exchange, conventionally the fax machine was connected to the extension side of the private telephone exchange, as shown in Figure 4, and the central office line CO for the fax line and the fax were connected. A one-to-one correspondence is established between extensions that accommodate faxes, and a program on the control device CC enables incoming and outgoing connections to the fax machine.When the fax machine is not in use, the general extension telephone EXT can also be connected to the central office line CO. It was possible to make outgoing calls.

That is, in FIG. 4, the connection route through which the fax F'AX is communicating with the central office line CO is the office@C〇--central office line trunk C0T--the route a'' indicated by the dotted line of the telephone line switch SP--extension circuit LC--FAX. F.A.
X, and the connection route during which extension telephone F2XT is talking to office line CO is office line C〇-office line trunk C0T-route b" shown by the dotted line of speech route suite SP-extension line circuit LC-extension telephone number EX
It is T.

[Problem that the invention seeks to solve]

In the conventional system described above, it is necessary to increase the number of extension circuits by the number of fax machines, which is not economical especially when accommodating a large number of fax machines.

However, if there is an incoming fax call on the central office line, extension connection control (dial-in connection control) is required, and the control program input to the control device fK becomes complicated.

The present invention has been proposed to solve the above problems, and an object of the present invention is to make it possible to accommodate faxes in an economical manner without increasing the number of extension circuits due to accommodating faxes and without complicated control. That is.

[Means for solving problems]

For the above purpose, in the present invention, fax connection control is configured as follows.

That is, a monitoring means for monitoring whether the central office line connecting the fax to the private branch telephone exchange is open or busy, and an opening/closing means for controlling the opening/closing of the communication path between the central office line and the fax are provided. When connected to the central office line by the opening/closing means and when a call is being made to the central office line, the central office line is used by the monitoring means to prevent the central line from being intercepted by a central line call from an extension, and the central office line is monitored. When the means detects that the central office line is unused, and the central office line is captured by a central office line call from an extension, the opening/closing means opens the communication path between the fax machine and the central office line. Calls from the above-mentioned f/m are now prohibited.

In addition, private telephone exchange equipment usually has a so-called central office line direct switching circuit that switches and connects the central office line to a specific extension telephone in case operations are stopped before nightfall or a failure occurs at a station. As the monitoring means and opening/closing means, the office line monitoring circuit, extension line, and office line changeover switch of this office line direct switching circuit are used as the monitoring means and opening/closing means. , the present invention can be implemented by reusing and modifying the program of the control device.

[Configuration of Example]

FIG. 1 is a relay system diagram showing an embodiment of the present invention. 1st
In the figure, central office line trunk COT K FAX FAX
The relay system is the same as that of the known automatic trench exchange device except that the relay system is connected.

FIG. 2 is a circuit diagram showing an embodiment of the present invention.

The office line CO is connected to the terminals CT and CR of the office line trunk COT, and the fax machine is connected to the terminal TLR, and the extension telephone EXT is connected to the terminals A and H via the communication route switch SP and extension circuit LC. has been done.

In the central office line trunk COT, terminals CT, CR and terminal A,
There is a communication path between question B and terminals CT, CR and terminals TLT and TLR, and control for opening and closing of the communication path between the communication path section TC and the office line monitoring circuit RC1 as a means for monitoring the office line status, and between the office line and FAX FAX. Break contacts pfl and pf2 of relay PF as a means to do this are connected. In addition, the base of the transistor Q that operates the output of the station line monitoring circuit RC and the relay PF is connected to the common control device C through the resistor R.
Connected to C.

The circuit shown in FIG. 3 is a direct line switching circuit that can be used in the present invention.
f' to p (4 is composed of a switching contact, contact pf'
, the make contact sides of pf2 are connected to terminals STT and S, respectively.
Terminals L1 and L2 of extension circuit LC via TR
It is connected to the. Also, the terminal TL of the central office line trunk COT
T.

TLR is used when the operation of the local telephone exchange equipment is stopped before night, and when there is a failure such as a power outage, the central office line
An extension telephone EXT is connected that provides direct communication. Other than these, the circuit is constructed almost the same as the circuit of the embodiment shown in FIG. Note that the terminal STT.

The connection between the STR and the terminals Ll and L2 of the extension circuit LC is normally configured so that it can be made arbitrarily, so when accommodating a fax machine, an extension telephone is connected to the terminals Ll and L2 of the extension circuit LC. Connect EXT, terminal STT,
Leave STR open and connect the terminal TL of the central office trunk COT.
If a fax machine is connected to T and TLR, the system will be similar to the embodiment shown in FIG.

[Effect of the embodiment]

In FIG. 1, communications by sending and receiving faxes are carried out through the following routes set under the control of the common control device fCC.

R) Line C0 - Office line trunk C0T - Fax AX If the fax is not yet in progress, the extension telephone EXT sends a call to the office line via the next route set under the control of the common control unit CC in the same way as above. I can make calls.

Extension phone f! kE
T-office @CO While the extension 'telephone EXT is talking to the office line CO on the above route, within the office line trunk COT, the fax FAX and the office line CO
The above-mentioned effects will be explained in detail with reference to FIG. 2, in which the communication path between CO and FAX is opened and calls to the central office line CO are prohibited.

In Figure 2, when the fax FAX is communicating with the office line C0, the office line C〇 - terminal terminal C open - office line monitoring circuit - contact pf' (
Non-operating side) One terminal TLT - FAX FAX one terminal TL
R - contact pf'' (non-operating side), one terminal CR - connected by the route of office line CO. At this time, a DC loop is formed with the office line CO via FAX, υ,
Since a DC loop current is flowing through the station line Co, the station line monitoring circuit RC detects the DC loop current and sends the detection signal (i.e. office line in use information) to the line t! It outputs to the common control unit CC through. The common control device CC reads this detection signal, knows that FAX communication is in progress, and prevents the central office line CO from being captured even if there is a central office line call from the extension telephone +*EXT.

When the fax FAX is not in communication, a direct current loop of the office line CO via the fax FAX is formed, so the q line c.

The DC loop current does not flow through the ring ζ. Therefore, the office line monitoring circuit RC does not output a detection signal of the DC loop current to the line t, and as a result, the control device CC immediately clears the office line Co. In this state, the office line of the extension telephone heating EXT is Transmission (C
Therefore, the central office line CO is in a state where it can be captured.

Here, the extension telephone EXT makes a call to the central office line and calls the above central office line CO.
When the above-mentioned office line CO and the above-mentioned extension telephone EXT are captured, the above-mentioned office line CO and the above-mentioned extension telephone EXT are: Office line C〇 - Terminal Terminal C open - Office line monitoring circuit - Communication path section TC
One terminal A - Channel switch SP - Extension circuit LC - C One terminal - 1 - Extension telephone T - Terminal L2 - Extension circuit LC - Channel switch SP - Terminal B - Channel section TC - Terminal CR - Office line CO connected by a path. At this time, since the office line trunk COT is captured from the extension telephone E XT side, a drive signal for the relay PF is sent from the common control device CC to the lead L, and the relay PF is activated. With this, υ contact p
f1 and p(1 break contacts open and fax 1
='A Since the communication path of X is disconnected from the central office line CO, outgoing calls from FAX are prohibited. Extension phone 7fi
While E
On the other hand, since a DC loop is formed and maintained in the communication path section TC, the station line monitoring circuit RC detects the DC loop current, and the detection signal is sent to the lead t.

Since all valves are sent to the control device CC (7), the control device CC is in the lead state! 4f: Relay PF continues to operate via FAX, and therefore, outgoing calls from FAX continue while extension telephone EXT is communicating with central office line CO.

The embodiment in which the central office line direct switching circuit shown in FIG. 8g3 is used is also constructed in the same way as the circuit in the embodiment shown in FIG. 2, so its operation is also similar to that in FIG.

However, in the central office line direct switching circuit, the relay PF is normally used as a constantly operating relay, but in this embodiment, the relay PF is always restored and the connection route for the fax F'AX is prepared, and the connection path from the extension telephone EXT is The control device C operates the relay PF when the station 11co is captured.
Construct a C program.

〔Effect of the invention〕

As described above, according to the present invention, faxes can be accommodated in a private telephone exchange without increasing the number of extension circuits, and extension connection control is not required for connection control.

In addition, by simply changing the program of the control device, the direct switching circuit that is normally provided in the central office line trunk can be used as is, so there is no need for a new central office line trunk to accommodate faxes, resulting in an extremely economical configuration. Faxes can be accommodated in a private branch telephone exchange.

[Brief explanation of the drawing]

Fig. 1 is a relay system diagram showing an embodiment of the present invention, Fig. 2 is a circuit diagram of an embodiment of the present invention, Fig. 3 is a circuit diagram showing a direct line switching circuit that can be used in the present invention, and Fig. 4 is a relay system diagram of a conventional example. (Main symbols) EXT...Extension telephone LC...Extension circuit SP/
・・Communication path switch CC・・Common control device COT・
... central office line trunk FAX ... fax CO ...
Office line PF... Relay pfl for controlling the opening/closing of the fax line or switching directly to the office line, pfl... Contact RC of relay PF... Office line monitoring circuit.

Claims (1)

[Scope of Claims] 1. In a private telephone exchange that accommodates a facsimile and enables communication between the facsimile and a central office line, the private telephone exchange determines whether the central telephone line is idle or busy. a monitoring means for monitoring, and an opening/closing means for controlling opening/closing of a communication path between the central office line and the facsimile, wherein the facsimile is connected to the central office line by the opening/closing means and is in communication with the central office line; In this case, the above-mentioned monitoring means prevents the above-mentioned office line from being captured by the office line call from the extension using the office line in-use information, and when the above-mentioned monitoring means detects that the above-mentioned office line is not in use, the communication from the extension is prevented. When the central office line is captured by a central office line call, the opening/closing means opens a communication path between the facsimile and the central office line to prohibit calls from the facsimile. facsimile connection method. 2. A facsimile connection system for a private telephone exchange according to claim 1, in which a central office line monitoring circuit, an extension line, and a central office line changeover switch of a central office line direct switching circuit are used as monitoring means and opening/closing means. .