JPH07203017A - Automatic incoming device - Google Patents

Abstract

PURPOSE:To prevent the connection between an object for connection and an unspecified subscriber making a call that is caused by an operating mistake on the center part. CONSTITUTION:A control circuit 15 turns on a switch 14 and connects an object for connection 2 to a circuit only when the off-hook state of an automatic incoming circuit 12 is detected by an off-hook state detecting circuit 13 and also an access signal is inputted from a center 5. If an on-hook operation is carried out at the center side in an input state of the access signal, the switch 14 is turned off by the circuit 15. Under such conditions, connection will never be made between the object 2 and an unspecified subscriber making a call even if an outgoing operation is made by this subscriber to the circuit 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic call receiving device for connecting a predetermined telephone line and an object to be connected via an automatic call receiving circuit.

[0002]

2. Description of the Related Art For example, in various unmanned test facilities and receiving facilities, as shown in FIG. 5, an automatic incoming circuit 3 is previously provided to a connection target 2 such as a test device or a receiving device in the facility 1. Built-in or connected externally, automatic incoming circuit 3 and telephone line L
Are connected to each other, and the center 5 sends a call to the telephone line L when necessary, so that the connection target 2 and the center 5 are connected to receive a test result, a received signal, or the like.

However, since the telephone line L is drawn into the facility 1 through the exchange 6, the automatic call receiving circuit 3 is set in the incoming state due to an erroneous call from other than the center 5, and the connection target 2 is not connected. There is a risk of connection with specific people.

For this reason, conventionally, in addition to a general telephone line, the control line L ′ is used to connect the center 5 to the facility 1, and the switch 4 is provided between the automatic call receiving circuit 3 and the connection target 2.
Is provided and the automatic call receiving circuit 3 is put into the off-hook state by first making a call from the center 5 to the telephone line L, and then the switch 4 is closed using the control line L'to perform a test or the like. After the test is completed, the switch 5 is opened and finally the center 5 is put into the on-hook state to release the off-hook state of the automatic incoming circuit 3.

[0005]

However, since the above-mentioned operation in the center 5 is usually performed manually by the operator, an operation error will always occur.

For example, without making a call to the telephone line L, the operation is interrupted while the switch 4 is turned on by the line L ', or the switch 4 by the line L'is used.
If you forget to cancel the above and cancel the operation by releasing the telephone line side to the on-hook state, the switch 4 always remains in the on state, and as described above, due to an erroneous call from other than the center 5 or an intentional call, This causes a serious problem that the connection target 2 and the unspecified caller are connected.

SUMMARY OF THE INVENTION It is an object of the present invention to solve this problem and to provide an automatic call receiving device in which a connection between an unspecified caller and a connection target does not occur even if there is an operation error on the center side.

[0008]

In order to solve the above problems, the automatic call receiving device of the present invention connects a predetermined telephone line (L) and a connection target (2) through an automatic call receiving circuit (12). A switch (14) for connecting the connection target to the automatic call receiving circuit in an automatic call receiving device for connecting between
Detecting means (13) for detecting that the automatic call receiving circuit is in an off-hook state in response to a call from the telephone line and outputting an off-hook signal, and for connecting the connected object to the automatic call receiving circuit. Only when both the access signal from the outside and the off-hook signal from the detection means are received, the switch is closed to connect the connection target and the telephone line, and the access signal and the off-hook signal are connected. And a control means (15) for opening the switch to disconnect between the connection target and the telephone line when the input of at least one signal is released.

[0009]

As described above, in the automatic call receiving device of the present invention, the switch is turned on only when the automatic call receiving circuit is in the off-hook state and the access signal to the connection target is input, and the telephone line is turned on. Is connected to the connection target, and when at least one of the signal inputs is released, the switch is opened to disconnect the telephone line from the connection target.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of an automatic call receiving device 1 according to an embodiment for connecting between one connected object 2 in a facility 1 and a center 5.
0 is shown.

The predetermined telephone line L drawn from the exchange 6 into the facility 1 is the line connection terminal 1 of the automatic call receiving device 10.
It is connected to the automatic incoming call circuit 12 via 1.

As shown in FIG.
When the call signal detection circuit 12b detects the input of the call signal to the line switch 12a on the one end side, the line control circuit 12
Under the control of c, the line switch 12a is operated to form a DC loop in the telephone line to be in an off-hook state, and an AC signal is applied between the one end side and the other end side of the line transformer 12d.
And the bidirectional transmission is made via the hybrid circuit 12e.

The detection signal from the ringing signal detection circuit 12b is output to the off-hook detection circuit 13. The off-hook detection circuit 13, for example, as shown in FIG. 2, closes the switch 13a by the detection signal of the ringing signal detection circuit 12b to energize and drive the photocoupler 13b (or a relay or the like), and outputs the output as an off-hook signal to be described later. Output to the control circuit 15, and when the incoming state is released, the switch 13a is opened. The diode 13c is a backflow prevention diode.

Between the automatic incoming call circuit 3 and the connection target 2,
It is connected through the switch 14. This switch 1
The opening and closing of 4 is controlled by the control circuit 15. The control circuit 15 receives the off-hook signal from the off-hook detection circuit 13 and the access signal from the control line L ′, and closes the switch 14 only when the access signal is input while the off-hook signal is being input. In other states, the switch 14 is controlled to remain open. The access signal is input to the control circuit 15 from the line terminating device 8 that terminates the control line L '(for example, a digital leased line).

When the center 5 sends a call to the telephone line L to the automatic call receiving device 10 thus constructed, the automatic call receiving circuit 12 enters an off-hook state, which is detected by the off-hook detecting circuit 13 to generate an off-hook signal. It is output to the control circuit 15.

The control circuit 15 receiving this off-hook signal
Since the access signal from the line L'is not input, the switch 4 remains open.

Next, when an access signal to the connection target 2 is sent from the center 5 through the line L ', the control circuit 15 closes the switch 14. As a result, the center 5 and the connection target 2 are connected by the telephone line L. Therefore, when the connection target 2 is a test device, the test result can be confirmed on the center side, and when it is a receiving device, the received signal can be confirmed on the center side.

The operator of the center 5 allows the connection target 2
When an operation for canceling access to the control circuit 15 is performed through the line L ', the access signal to the control circuit 15 is not input, so that the switch 14 is opened. Next, when the operator performs an on-hook operation on the telephone line L, the off-hook state by the automatic incoming circuit 12 is released, and the off-hook signal to the control circuit 15 is no longer output.

Here, for example, if the operator of the center 5 makes a line L '
Even if the operation is terminated by on-hooking the telephone line side without forgetting to release the access signal by the off-hook detecting circuit 1 by the on-hook operation of the telephone line L.
Since the on-hook signal from 3 is not output to the control circuit 15, the switch 14 is opened and the automatic call receiving circuit 12 and the connection target 2 are disconnected even when the access signal is being input.

Therefore, even if a person other than the center 5 makes a call to the telephone line L in this state, the connection target 2
Never be connected to.

Although the above embodiment is an example of the automatic call receiving device for one connected object, it is provided for each of a plurality of connected objects 2 ₁ to 2 _n in the same facility 1 in FIG. An example of the automatic call receiving devices 20 _{1 to} 20 _n will be shown.

In FIG. 3, each of the automatic call receiving devices 20 _{1 to} 20
_n is configured identically, likewise, automatic call circuit 12 ₁ to 12 _n which has received the call signal from the line connection terminals 11 ₁ to 11 _n becomes reception state and automatic call device 10 of the embodiment This is detected by the off-hook detection circuits 13 _{1 to} 13 _n , and the off-hook signal is detected by the control circuits 15 ₁ to 15 _n.
Output to. Each of the control circuits 15 ₁ to 15 _n closes the switches 14 _{1 to} 14 _n only when it receives an access signal for the connection target 2 ₁ to 2 _n while receiving the off-hook signal, and inputs at least one signal. When the switch is released, the switches 14 _{1 to} 14 _n are opened.

Receiving circuit selection switches 21 _{1 to} 21 _n are provided between the automatic receiving circuits 12 _{1 to} 12 _n and the switches 14 _{1 to} 14 _n of the automatic receiving devices 20 _{1 to} 20 _n , respectively. This incoming circuit selection switch 21 _{1 to} 21
_{For n} , only the switch of the automatic call receiving device 20 ₁ to which the telephone line L is connected among the plurality of automatic call receiving devices is set to the on state, and the other switches are set to the off state.

At the connection points of the incoming circuit selection switches 21 _{1 to} 21 _n and the switches 14 _{1 to} 14 _n , interconnection terminals 22 _{1 to} 22 _n and 23 ₁ to 23 _n are provided, respectively, and the automatic incoming device 20 ₁ Each of the ~ 20 _n interconnection terminals is continuously connected. Further, the detection connection terminals 24 _{1 to} 24
_n is connected to the connection point between the switch 13a and the photocoupler 13b of each hook detection circuit 13 ₁ to 13 _n (see FIG. 2), between the sensing connection terminal is continuously connected.

Therefore, when any one of the automatic incoming circuits goes into the off-hook state and the switch 13a is closed,
The photocoupler 13b of the other off-hook detection circuit is also turned on, and the off-hook signal is output.

The automatic call receiving device 20 connected as described above.
_When a call operation from the center 5 side to the telephone line L is performed for _{1 to} 20 _n , a call signal is input to the automatic call receiving circuit 12 ₁ of the automatic call receiving device 20 ₁ , and the telephone line L goes off-hook. An off-hook signal is output from the off-hook detection circuit 13 ₁ to the control circuit 15 ₁ . At this time, another automatic call receiving device 20 _2-
The off-hook signal is also output to the 20 _n control circuits 15 ₂ to 15 _n .

Next, from the center 5 side, for example, the connection target 2
_When an access signal designating ₂ is sent to the line L ',
An access signal is input to the control circuit 15 ₂ via the control line terminating device 8.

Therefore, the switch 14 ₂ is closed, and the automatic call receiving circuit 12 is provided between the telephone line L and the connection target 2 _2.
1 , incoming circuit selection switch 21 ₁ , mutual connection terminal 2
3 ₁ , the connection terminal 22 ₂ and the switch 14 ₂ are connected. Further, when an access signal for another connected object is input, the switch corresponding to the connected object is closed and the telephone line is connected.

In this configuration, even if the operation is terminated by forgetting either the access release or the on-hook operation to the telephone line L side due to an operation mistake on the side of the center 5, the switches 14 _{1 to} 14 _n are always operated. Since it is opened, an unspecified caller other than the center and the connection target are not connected.

In the embodiment shown in FIG. 3, the automatic receiving device 2
All of the 0 _{1 to} 20 _n are provided with the automatic call receiving circuits 12 _{1 to} 12 _n, but this is for easily responding to the increase or decrease of the number of objects to be connected. The automatic call receiving circuits 12 _{2 to} 12 _n of the automatic call receiving devices 20 _{2 to} 20 _n which are not connected may be omitted. Further, in this embodiment, the connection points of the switch 13a of each off-hook detection circuit 13 _{1 to} 13 _n and the photocoupler 13 b are connected to each other so that the off-hook signal is output to all the control circuits 15 ₁ to 15 _n. which was, all of the control circuit of the off-hook signal from one of the off-hook detection circuit 15 ₁ to 15 _n
You may make it output to. In this case, a photocoupler may be provided on the control circuit side, or the output of each off-hook signal may be wired or connected.

Further, in the above embodiment, the connection target
Receiving an access signal from another line L '
As explained above, as shown in Fig. 4, the telephone line is
Receives the access signal input from the center 5 via L
Then each control circuit 15₁~ 15_nAccess signal output to
The receiving circuit 40 is replaced by the automatic receiving circuit 12₁And switch 14 ₁
It may be provided between and.

Further, in the above embodiment, the case where the connection target 2 is a test device, a receiving device or the like has been described. Can be similarly applied.

[0033]

As described above, the automatic call receiving device of the present invention can be operated only when both the off-hook signal indicating that the automatic call receiving circuit is in the off-hook state and the access signal to the connected object are input. The switch between the automatic call receiving circuit and the connection target is closed, and the switch is opened when the input of one of the signals is released.

Therefore, even if the operation error on the center side occurs,
Even when the operation is terminated while forgetting either the release of the access signal or the on-hook operation to the telephone line side, it is possible to prevent the connection between an unspecified caller other than the center and the connection target.

[Brief description of drawings]

FIG. 1 is a block diagram showing an automatic call receiving device according to an embodiment of the present invention.

FIG. 2 is a block diagram of a main part of one embodiment.

FIG. 3 is a block diagram showing another embodiment of the present invention.

FIG. 4 is a block diagram showing another embodiment in which an access signal is received from a telephone line.

FIG. 5 is a diagram showing a configuration of a conventional device.

[Explanation of symbols]

1 Facility 2, 2 _{1 to} 2 _n Connected target 5 Center 6 Switch 8 Control line terminating device 10, 20 _{1 to} 20 _n Automatic incoming call device 12, 12 _{1 to} 12 _n Automatic incoming call circuit 13, 13 _{1 to} 13 _n Off-hook detection Circuit 14, 14 _{1 to} 14 _n Switch 15, 15 ₁ to 15 _n Control circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takahiro Nakamura 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation (72) Inventor Koji Sahara 4-19-7 Kamata, Ota-ku, Tokyo Ando Denki Co., Ltd.

Claims (1)

[Claims] 1. An automatic receiving device for connecting a predetermined telephone line (L) and a connection target (2) through an automatic reception circuit (12), wherein the connection target is connected to the automatic reception circuit. A switch (14) for operating the automatic call receiving circuit, a detection means (13) for detecting that the automatic call receiving circuit is in an off-hook state in response to a call from the telephone line, and outputting an off-hook signal; The switch is closed only when both an external access signal for connecting to the automatic incoming circuit and an off-hook signal from the detection unit are received, and the connection target and the telephone line are connected to each other, When the input of at least one of the access signal and the off-hook signal is released, the switch is opened to disconnect the connection target and the telephone line. Automatic call device being characterized in that and means (15).