JPS6386692A - Line trunk interface device - Google Patents

Abstract

PURPOSE:To contrive to normalize the BORSCHT function of a line interface circuit by performing either connection to a resistance circuit of the inductance circuit of an adaptor circuit at the time of on-hooking and switching to the inductance circuit side of the adaptor circuit at the time of off-hooking. CONSTITUTION:At the time of on-hooking, it is connected to a pure resistance 11, and in this situation, when a terminal is made to come to the OFF-HOOK, the OFF-HOOK state is detected by a detection circuit 7, and a switching power source circuit 6 is connected to a line by switching the contact (r) of a relay R, then it comes to be an inherent adaptor circuit constitution. Besides, at the time of on-hooking a Ringing can be normally transmitted from the line interface circuit, and also, the line can be normally tested. Further, the detection circuit 7 can be commonly used as the detection circuit of the line interface circuit. Thus, the BORSCHT function of the line interface circuit can be normally performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a line trunk interface device, and particularly to an improvement of an adapter circuit for a line ink face circuit.

[Conventional technology]

FIG. 3 is for explaining the most suitable configuration of a line trunk interface device to which the present invention can be applied. It shows the connection relationship of a circuit for adding various external functions, that is, an adapter circuit 2.

Terminal 4 is connected to adapter circuit 2 by line 3.

As the adapter circuit 2, for example, the following one is used. One of them is a common mode choke 5 as shown in FIG. 3(B) for guarding AC induction (commercial line induction) induced into the circuit 3. The other one is a switching power supply circuit 6 having a switching power supply 8 as shown in FIG. 3(C).

In other words, in order to extend the distance of the circuit 3, a boost function is required to increase the value of the communication current, but this is achieved by inserting the switching power supply circuit 6 into the line 3 in series, as shown in Figure 3 (C). This is achieved by

In this way, the adapter circuit 2 is a common mode choke 5 or a switching power supply circuit 6, both of which have an inductance component, and are used as the adapter circuit 2 of the line interface circuit 1. .

[Problem that the invention seeks to solve]

However, since these have an inductance component, the BOR3C, which is the basic function of the line interface circuit 1,
The HT function cannot be fully satisfied.

In other words, “R” (Rin) in the BOR3CRT function
ging ; ringing) function, 'T''(Test
;Test) functions are the target, and these functions cannot be fully utilized.

First, the "T' function is a so-called exchange test function, and is necessary to measure line impedance such as the ground-to-ground capacity of line 3 and check the normality of line vA3, and is normally required from an exchange. An AC waveform is sent and the impedance is measured, but in this case, if an inductance component exists, the impedance of the adapter circuit 2 is added to the original line impedance, making it impossible to check properly.

In this way, conventionally, the adapter circuit 2 of the line ink face circuit 1 is connected to the line 3 from the line ink face circuit 1.
When testing the impedance (leakage resistance value of two lines, etc.), for example, the inductance of a choke coil to guard against commercial line induction as shown in Figure 3 (B), Figure 3 (C) The inductance of the transformer on the secondary side of the switching power supply circuit 6 for boosting the direct current in the line 3 is added to the impedance of the line 3, so there is a drawback that accurate testing is not possible.

In addition, the "R" function sends a ringing signal (Ringin) to the terminal 4.
It is a function to send a signal (frequency: 16 Hz to 6611 z), but in this case, the voltage is divided in the inductance, making it impossible to send a normal calling signal to the terminal 4.

In such a case, the terminal 4 stops ringing. in this way,
Ringing signal (
When sending a ringing signal (ring signal) to terminal 4, if there is also an inductance component, the voltage of the Ringing signal will be divided by the inductance component, and a normal Ringing signal waveform will not be sent to terminal 4, and the ring tone of terminal 4 will not be normal. The disadvantage is that it does not make a sound.

An object of the present invention is to fully satisfy the function of a line ink face (BOR3CHT function, which is the basis of a line ink face circuit) in a line trunk interface device configured with an adapter circuit having an inductance circuit. It is to do so.

Means for Solving Problem c] The present invention provides a line trunk interface device that includes a line trunk interface circuit and an adapter circuit, and the adapter circuit has an inductance component. and a switching means that is controlled by the detection means and connects to a resistance circuit or shorts the inductance circuit of the adapter circuit when on-hook, and switches to the inductance circuit side of the adapter circuit when off-hook. It is characterized by

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which a line trunk interface device is provided with a line interface circuit and an adapter circuit, and the adapter circuit has an inductance circuit.
The configuration is shown when applied to an example using a switching power supply circuit as shown in C). In the configuration shown in FIG.
・0NHOOK10FF HOOK detection circuit 7 for detecting an off-hook state, a relay R having a relay contact r, a resistor 11 as a pure resistance circuit, and in this case, in the example shown in FIG. 3(C). A switching power supply circuit 6 having a switching power supply 8 is provided.

Each contact r of the relay R is provided to selectively connect each winding as an inductance circuit of the switching power supply circuit 6 and the pure resistor 11, and the relay R is controlled by the detection output of the detection circuit 7. , in the ON HOOK state, connect relay contact r to resistor 1 as shown in Figure 1.
1 side, and when in the OFF HOOK state, it is switched to the winding side of the switching power supply circuit 6.

In this way, the adapter circuit connects line 3's 0NHOOK(
○N800K (on-hook)
When it is connected to the pure resistance circuit of the adapter circuit, it is OFF.
When HOOK (off-hook), it is connected to the inductance circuit of the adapter circuit.

The adapter circuit with such a configuration is shown in Fig. 3(A).
Similarly, it is provided between the line interface circuit 1 and the terminal 4.

Next, the operation of this embodiment will be explained.

First, when the hook is ON, it is always connected to the pure resistor 11 as shown in FIG. In this state, terminal 4 is turned off.
When F HOOK is performed, the detection circuit 7 turns OFF )(
The OOK state is detected and contact r of relay R is switched, thereby connecting switching power supply circuit 6 to line 3. Once connected, it becomes the original adapter circuit configuration. Also, by configuring as shown in Fig. 1, ON H
When ooK, Ri is normally sent from line ink face circuit 1.
nging can be sent and the Tes L of line 3 can be sent normally.
You will be able to do this. Note that the detection circuit 7 can also serve as a detection circuit for the line ink face circuit 1.

FIG. 2 shows another embodiment of the present invention, and FIG. 3(B) shows an adapter circuit equipped with an inductance circuit.
This is an example applied when using the common mode choke shown in FIG.
HOOKloFF Detects the state of Hoo and turns it on
The configuration is such that the inductance of the common mode choke 5 is short-circuited during HooK.

With the above configuration, the BOR3CHT function of the line ink face circuit 1 can be performed normally.

As described above, according to each embodiment, in a line trunk interface device in which the adapter circuit includes an inductance circuit, even if the adapter circuit is a circuit having an inductance component, it is possible to determine whether the impedance of line 3 is normal. Please check Te5t function, Ring
The Ringing function in which the Ringing voltage is normally sent can be fully satisfied.

When testing the impedance of line 3 from line ink face circuit 1 or when sending a calling signal to terminal 4,
The inductance of the adapter circuit can prevent accurate testing and prevent the ringer from working properly, and detects the ON HOOK (on hook) and 0FF HOOK (off hook) functions of line 3. (on-footer), connect the pure resistance circuit of the adapter circuit or short-circuit its inductance circuit, and when OFF-HOOK (off-hook), connect the adapter circuit to a circuit that has the original function (for example, common mode choke 5 in Figure 2). T'' function by connecting to the switching power supply circuit 6) of FIG.

"R" function can be performed normally.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a line trunk interface device that can fully satisfy the line interface function even if the adapter circuit used has an inductance component.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing one embodiment of the present invention, FIG. 2 is a diagram showing another embodiment of the present invention, and FIG. 3 is a diagram for explaining a conventional example. 1... Line ink face circuit 2... Adapter circuit 3... Line 4... Terminal 5... Common mode choke 6... Switching power supply circuit 7... On hook / off-hook) Grilling circuit 8...
・Switching power supply 11...Pure resistance R...Relay r...Relay contact

Claims (1)

[Claims] (1) A line trunk interface device comprising a line trunk interface circuit and an adapter circuit, the adapter circuit having an inductance component, a detection means for detecting on-hook and off-hook states of the line, and switching controlled by the detection means, A line trunk interface device comprising a switching means that connects to a resistance circuit or shorts an inductance circuit of the adapter circuit when on-hook, and switches to the inductance circuit side of the adapter circuit when off-hook.