JPS6249745A - Circuit switching device - Google Patents

Abstract

PURPOSE:To execute a quite same operation even when a terminal is connected with a switching circuit or a private line, by connecting a control signal sending circuit and control signal detecting circuit to a private line side and sending a direct current and call signal to the terminal equipment through a call signal generating circuit. CONSTITUTION:When a calling side terminal equipment 1 makes a call by using a switching circuit, a relay RL is under an unactuated condition and the terminal equipment 1 is connected with an exchange 3 through the normal contact of a relay RL and a switching circuit S, and thus, the terminal equipment 1 can be connected with an optional terminal through the exchange 3. When communication is made with an incoming side terminal equipment 11 through a private line, the relay RL is actuated by means of a control circuit 4 and the terminal 1 is connected with a call signal generating circuit 9 through the switching contact of the relay RL. Since a direct current is supplied from the circuit 9 to the terminal 1, the terminal can operate under the same condition as that obtained when the terminal 1 is connected with the switching circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a line switching device for arbitrarily switching and connecting a facsimile device or a data terminal device to a switched line or a dedicated line.

〔overview〕

The present invention provides a line switching device that arbitrarily switches and connects a terminal device to a switched line or a leased line. By being equipped with a control signal transmission path, a control signal detection circuit, and a control circuit that controls these operations, the terminal device can automatically receive a call using the same operation regardless of the connected line. This is what I did.

[Conventional technology]

Conventionally, in order to use facsimile equipment, data terminal equipment, etc. in common for switched lines and leased lines, it is possible to arbitrarily switch connections between switched lines and leased lines through a line switching device, as shown in Fig. 3. As shown, a terminal device 1 is connected to a converter 2, a normal contact side of the converter 2 is connected to an exchange 3 through a switching line S, and a switching contact side of the converter 2 is connected to a dedicated line.

[Problem that the invention seeks to solve]

In the conventional circuit described above, if the dedicated line is a line that can pass direct current, it is possible to switch the line using a private branch exchange, etc., but it is possible to switch the line using a private branch exchange, etc. In this case, there is a drawback that the private branch exchange etc. cannot be used as is.

In addition, if the converter 2 is switched manually, it is not possible to receive calls automatically, and if the terminal device is equipped with a special interface so that it can receive calls automatically, the terminal device requires special modification, which is expensive. Another drawback is that it lacks versatility.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional drawbacks and provide a line switching device that can arbitrarily switch and connect a general-purpose terminal device between a switched line and a dedicated line, and can also automatically receive calls. do.

[Means for Solving the Problems] The line switching device of the present invention is a line switching device that arbitrarily switches and connects a terminal device to a switched line and a leased line. a calling signal generation circuit that supplies signals and direct current; a control signal transmission circuit and a control signal detection circuit connected to the dedicated line;
The present invention is characterized by comprising a control circuit that controls the switching of the switching contacts and the operations of the calling signal generation circuit, the control signal transmission circuit, and the like.

[For production]

No matter which line the terminal device is connected to, it can automatically receive a call by the same operation.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

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

That is, the terminal device 1 is connected to the common contact of the relay RL, the normal contact side of the relay RL is connected to the exchange line S via the loop detection circuit 5, and the switching contact side of the relay RL is connected to the call signal generation circuit 9 and the loop. It is connected to a dedicated line via the detection circuit 5.

A control signal sending circuit 7 is connected to the sending side S of the exclusive port 'iaL, and a control signal detecting circuit 8 is connected to the receiving side r. These operations are controlled by the control circuit 4. Further, a calling signal detection circuit 6 is connected to the exchange line.

Next, the operation of this embodiment will be explained with reference to FIGS. 1 and 2. Figure 2 shows two terminal devices 1 and 11.
are connected to the exchanges 3 and 13 through the line switching device 10 of this embodiment, respectively, and the line switching devices 10 are connected to each other by a dedicated line.

When the originating terminal device 1 makes a call using a switched line, the relay RL is in an inactive state, and the terminal device 1 is connected to the exchange 3 via the switched line S through the normal contact of the relay RL, and the exchange 3 Can be connected to any other terminal via. Further, an incoming call from any other terminal is detected by the paging signal detection circuit 6, and the connection is completed by a response from the terminal device 1. At this time, the response of the terminal device 1 is detected by the loop detection circuit 5 and reported to the control circuit 4. While the loop detection circuit 5 is detecting a loop, the control circuit 4 prevents the relay RL from operating.

When the terminal device 1 communicates with the called terminal device 11 through a dedicated line, the control circuit 4 operates the relay RL to connect the calling signal generation circuit 9 to the terminal device 1 through the switching contact of the relay RL. Since the calling signal generating circuit 9 sends a direct current to the terminal device 1, the terminal device 1 can operate under exactly the same conditions as when connected to an exchange line. Further, the loop state of one example of the terminal device is detected by the loop detection circuit 5 and reported to the control circuit 4, and the control circuit 4 does not restore the relay RL until the loop is disconnected. Further, a control signal is transmitted from the control signal output path 7 to a dedicated line, and this control signal is detected by the control signal detection circuit 8 on the receiving side terminal device 11 and reported to the control circuit 4. The control circuit 4 on the called terminal device II side operates the relay RL, and at the same time sends a calling signal from the calling signal generation circuit 9 to the called terminal device 11. and the originating terminal device 1 are connected by a dedicated line. At this time, the called terminal device 11 performs an automatic call receiving operation based on the calling signal from the calling signal generating circuit 9, but since the calling signal sent from the calling signal generating circuit 9 is the same as the calling signal of the switched line, the called terminal The device 11 can perform a call receiving operation without being particularly aware of the receiving line.

The response from the receiving terminal device 11 is detected by the loop detection circuit 5, and the relay RL will not be restored on the receiving terminal device 11 side until this loop is broken. When the communication ends and the loop on the terminal side is released, each loop detection circuit 5 detects the loop disconnection and reports it to each control circuit 4, and each control circuit 4 restores relay RL and disconnects the loop from each terminal. is again connected to the switched line S side.

In this embodiment, the terminal device can automatically receive a call by the same operation regardless of which line it is connected to, without being particularly aware of the line to which it is connected.

〔Effect of the invention〕

As explained above, in the present invention, the control signal sending circuit and the control signal detecting circuit are connected to the dedicated line side, and the direct current and the calling signal are sent to the terminal device through the calling signal generating circuit. The terminal device can operate in exactly the same way whether it is connected to a switched line or a leased line, and can be connected to either a switched line or a leased line without providing a special interface to the terminal device. What's more, it has the effect of automatically receiving calls.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention. FIG. 2 is a diagram showing an example of a connection configuration using the above embodiment. FIG. 3 is a diagram showing an example of a connection configuration of a conventional line switching device. 1... Terminal device, 2... Converter, 3... Switching machine,
4... Control circuit, 5... Loop detection circuit, 6...
Calling signal detection circuit, 7... Control signal output path, 8.
...Control signal detection circuit, 9...Call signal generation circuit,
1o...Line switching device, 11...Receiving side terminal device,
RL...relay, S...switched line, L...dedicated line.

Claims (1)

[Claims] (1) The connection line of the terminal device is a switched line (S) and a leased line (S).
L) in a line switching device that switches and connects to the terminal device, and a ringing signal generation circuit (9) that supplies a ringing signal and direct current to the terminal device via a switching contact, and a ringing signal generation circuit (9) that is connected to the dedicated line and sends a control signal to the dedicated line. A control signal detection circuit (8) that detects a control signal transmission circuit (7) that transmits a control signal and a control signal that arrives on the dedicated line; and a control circuit that controls the switching contact, the calling signal generation circuit, and the control signal transmission circuit. (4) A line switching device characterized by comprising: