JP3702725B2 - Telephone line / door phone switching adapter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a telephone line / doorphone switching adapter for switching and connecting a telephone line and a door phone to a communication device such as a telephone.
[0002]
[Prior art]
FIG. 4 is a block diagram showing an example of an internal configuration of a conventional telephone line / doorphone switching adapter (hereinafter also simply referred to as “adapter”). The illustrated adapter 100 is connected to a telephone line L so as to connect a door phone 300 and an additional connection of a telephone 200. It is also configured as an intercom installed in each dwelling unit of the apartment house, and is connected to the monitoring panel 400 installed in the center of the apartment house (monitoring room, security room, etc.) via the telephone line L1 and the control line L2. ing.
[0003]
Since this adapter 100 also has a call function, the adapter 100 can communicate with the monitor panel 400 installed in a monitoring room, a security room, etc. In addition to enabling communication and communication with the collective entrance handset 500 (lobby intercom) connected to the monitoring panel 400, the telephone 200 can also control the telephone line L, the door phone 300, and the monitoring panel 400 by switching control of the adapter 100. , Communication with the collective entrance child device 500 is made possible.
[0004]
The adapter 100 includes a CPU and the like, and includes a control unit 110 that controls the following units, a switching relay 111 that switches the connection of the telephone 200 between the telephone line L and the door phone 300, and the usage state of the telephone line L. An external line use state detection circuit 112 for detecting a call, an incoming call detection circuit 113 for detecting a call through the telephone line L, a dial detection unit 114 for detecting a dial signal from the telephone 200, a door phone 300, a monitoring panel 400, a collective entrance A doorphone call control circuit 115 that controls a call with the handset 500, a call circuit 116 having a speaker SP and a microphone MI, and a ringing tone are generated from the adapter 100 itself in order to make a call with the adapter 100 itself. And a call button 11 that is operated when responding in order to make a call with the adapter 100. It is provided with a.
[0005]
During normal standby, the switching relay 111 connects the telephone 200 to the telephone line L, and the doorphone call control circuit 115 detects a call from any one of the doorphone 300, the monitoring panel 400, and the collective entrance handset 500. Then, control unit 110 switches switching relay 111 to connect telephone 200 and door phone call control circuit 115, and sends a call signal (60 Hz, approximately 180 Vp-p) from door phone call control circuit 115 to telephone 200. To do.
[0006]
If the telephone 200 responds to this call by picking up the handset, etc., the doorphone call control circuit 115 stops sending the call signal and shifts to a call state between the telephone 200 and the doorphone 300 or the like.
In the telephone 200, for example, when a predetermined dial operation (for example, dialing “5”) is performed during a call with the central entrance 500, the dial detection unit 114 detects this, and the control unit 110 controls the control line L2. An unlock signal is sent through. Then, the electric lock on the side of the collective entrance child device 500 can be unlocked. Thereafter, when the telephone set is returned to the original state in the telephone set 200, the switching relay 111 is switched to connect the telephone line 200 and the telephone line L.
[0007]
When a call from the door phone 300 or the like is detected, a ringing sound can be output from the adapter 100 itself by the ringing tone generator 117 and a doorphone call can be made in response by operating the call button 118.
Further, when the doorphone call control circuit 115 detects a call from the doorphone 300 side in a state where the external line use state detection circuit 112 detects that the telephone 200 is making a call via the telephone line L, A call signal is transmitted and superimposed on the call signal, and a ring tone is also output from the ring tone generator 17. On the other hand, when the telephone 200 responds by returning the handset (on-hook) or the like, the call through the telephone line L is terminated, and if the handset is picked up again (off-hook), the call with the door phone 300 can be started. . In addition, in the adapter 100, a door phone call can be made in response to an operation of the call button 118. At this time, the telephone call 200 can be continued.
[0008]
On the other hand, when a call signal is sent through the telephone line L during a call with the door phone 300 or the like in the telephone 200, the incoming call detection circuit 113 detects this, and the door phone call control circuit 115 sends a call signal. Superimpose on the call signal. On the other hand, when the telephone 200 responds by returning the handset (on-hook) or the like, the call with the door phone 300 or the like is terminated, and if the handset is picked up again (off-hook), the telephone call can be started via the telephone line L. .
[0009]
[Problems to be solved by the invention]
However, since the conventional telephone line / door phone switching adapter is provided with an external line usage state detection circuit (112 in FIG. 4) for detecting the usage state of the telephone line in series with the telephone line, the telephone line to be used is When changing from an analog line to a digital line such as ISDN, if a digital signal passes through the external line usage state detection circuit, the signal waveform may be attenuated or distorted, which may hinder communication such as a transmission error. . That is, in the outside line use state detection circuit, the use of a telephone line is determined based on the current flowing in the coil using a coil. Therefore, if the resistance value of the coil increases, signal attenuation or the like occurs. .
[0010]
FIG. 5 is a diagram showing the relationship between the resistance value by the external line use state detection circuit and the frequency of the signal passing through this circuit. When the telephone line is an analog line, the resistance value does not increase because the telephone band is a low frequency, but the resistance value increases in the high frequency band of the digital signal.
Further, since the conventional telephone line / door phone switching adapter is provided with an incoming call detection circuit (113 in FIG. 4) in order to detect a call signal (16 Hz) transmitted from the telephone line, the telephone line is a digital line. In this case, the incoming call detection circuit becomes an extra load, causing attenuation or distortion in the signal waveform, which may hinder communication such as a transmission error.
[0011]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a telephone line / doorphone switching adapter that can perform normal communication even when the telephone line is changed to a digital line.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the present invention connects a telephone line and a door phone installed at the entrance of a dwelling unit, etc., and connects a communication device, and switches and connects either the telephone line or the door phone. The improvement of the telephone line / doorphone switching adapter that enables communication by the communication device is proposed.
[0013]
Here, when the telephone line is an analog line, the communication apparatus includes a normal analog telephone, a facsimile apparatus equipped with a modem, a personal computer, and the like. When the telephone line is a digital line, a digital telephone, a G4 facsimile apparatus, a television set. There are telephones, telephones connected to terminal adapters (TA), personal computers, and the like. Note that a DSU (line termination device) and a TC (home control device) connected to the DSU are also included in this communication device.
[0014]
According to a first aspect of the present invention, a current detection circuit connected in series to the telephone line in order to detect the usage state of the telephone line is configured to suppress an increase in resistance value due to the passage of a high-frequency signal. The current detection circuit includes a coil that is connected in series to a telephone line and detects a current, and a capacitor that is connected in parallel to the coil.
[0015]
A second aspect of the present invention is characterized in that the resonance frequency of the coil and the capacitor is a frequency other than the speech frequency band of the analog signal and the frequency band of the digital signal.
[0016]
According to a third aspect of the present invention, switch means for disconnecting the connection between the telephone line and the incoming call detection circuit is provided between the telephone line and the incoming call detection circuit for detecting the call signal transmitted through the telephone line, In the case of a digital line, the switch means disconnects the connection between the telephone line and the incoming call detection circuit.
Here, there are ISDN (integrated service digital communication network) and DDX network (digital data exchange network) as digital lines. When connected to a digital line, an incoming call detection circuit for detecting a ringing signal (16 Hz) transmitted as an analog signal is not necessary, and communication with the door phone side by a communication device is prohibited. Since it is not necessary to detect the ringing signal transmitted by the telephone line, there is no problem even if the connection between the telephone line and the incoming call detection circuit is disconnected. When connecting to an analog line such as a telephone network or a broadcast network, the switch means does not disconnect the connection between the telephone line and the incoming call detection circuit.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing an example of the configuration of a telephone line / door phone switching adapter. The telephone line / door phone switching adapter 1 connects the telephone line L and the door phone 3 installed at the entrance of the dwelling unit, etc., and also connects a communication device such as a telephone, so that either the telephone line L or the door phone 3 is connected. The connection is switched to enable communication by the communication device.
[0018]
The door phone 3 is not limited to one, and may be a plurality. Also, a plurality of communication devices can be connected. In these cases, switching control is performed between the plurality of doorphones 3 or between the plurality of communication devices.
When the telephone line L is an analog line, an ordinary analog telephone, a facsimile machine equipped with a modem, a personal computer, or the like is connected as a communication apparatus. When the telephone line L is a digital line, a digital telephone, A G4 facsimile apparatus, a video phone, a telephone connected to a terminal adapter (TA), a personal computer, and the like are connected. Note that a DSU (line terminating device) and a TC (home control device) connected to the DSU are also included in the communication device connected to the digital line.
[0019]
Therefore, when connecting to an analog line, an analog terminal such as an analog telephone or a modem is connected and no DSU or the like is required. When connecting to a digital line, an ISDN telephone or digital terminal is connected.
Analog lines include telephone networks and broadcast networks, and digital lines include ISDN (integrated service digital communication network) and DDX network (digital data exchange network). In this figure, the telephone line L is an ISDN that is a digital line, and shows a case where a DSU 2 is connected as a communication apparatus, and a communication apparatus such as a telephone is further connected to the DSU 2. Yes.
[0020]
Here, a case where the adapter 1 is connected to the telephone line L before the DSU 2 is shown, but the present invention is not limited to this, and the latter stage of the DSU 2 connected to the telephone line L. The structure which connects the adapter 1 to may be sufficient.
The adapter 1 according to the present invention is not only capable of switching and connecting the telephone line L and the door phone 3, but also can be switched and connected to a monitoring panel 4 or the like installed in a monitoring room of an apartment house. The configuration in that case is shown. Therefore, this adapter 1 is applicable also to the dwelling unit of an apartment house other than a single-family dwelling unit.
[0021]
The adapter 1 and the monitoring panel 4 are connected via a communication line L1 and a control line L2 that performs multiplex transmission. The monitoring panel 4 further includes a collective entrance cordless handset installed at the common entrance of the apartment house. 5 (lobby intercom) is connected.
Here, the adapter 1 is further configured as an interphone installed in each dwelling unit of the apartment house. In this adapter 1 itself, a call with the door phone 3, a call with the monitor panel 4, and a connection to the monitor panel 4 are further made. It is possible to make a call with the collected collective entrance 5. Here, it is assumed that the adapter 1 itself does not include a communication function through the telephone line L without including a dial operation unit, but is not limited thereto.
[0022]
As in the conventional configuration shown in FIG. 4, this adapter 1 is composed of a CPU or the like, and is composed of a control unit 10 that controls the following units, a relay, and the like, and is connected to the communication device side such as DSU 2. A switching unit 11 that switches between the telephone line L and the door phone 3, an external line usage state detection circuit 12 that detects the usage state of the telephone line L, and an incoming call detection circuit 13 that detects a call signal through the telephone line L , A dial detection unit 14 for detecting a dial signal from the communication device side, a door phone call control circuit 15 for controlling a call with the door phone 3, the monitoring panel 4, and the collective entrance handset 5, and a call by the adapter 1 itself. In order to perform the call, the call circuit 16 having the speaker SP and the microphone MI, the ringing tone generator 17 for generating a ringing tone from the adapter 1 itself, and the response for making a call with the adapter 1 It is provided with a call button 18 to be operated. The adapter 1 is not limited to the configuration for performing a hands-free call as shown in the figure, and may be configured with a handset.
[0023]
The external line usage state detection circuit 12 constitutes a current detection circuit connected in series to the telephone line L in order to detect the usage state of the telephone line L. Although the use state of the line L is determined, in the present invention, the circuit 12 is configured to suppress an increase in resistance value due to the passage of a high-frequency signal. Specifically, it is composed of a coil CO that is connected in series to the telephone line L and detects a current, and a capacitor C that is connected in parallel to the coil CO. Further, as shown in the relationship between the frequency and the resistance value in FIG. 2, the resonance frequency of the coil CO and the capacitor C is set to a frequency other than the analog signal speech frequency band and the digital signal frequency band (arrow P in the figure). .
[0024]
According to the present invention, as shown in the figure, when the telephone line L is changed to a digital line, even if a high-frequency digital signal passes through the outside line usage state detection circuit 12, it is possible to suppress an increase in resistance value. Therefore, normal communication can be performed without any signal attenuation or distortion. Also, normal communication can be realized with a simple configuration in which the capacitor C is provided. Further, since the resonance frequency of the coil CO and the capacitor C is set to a frequency other than the analog signal speech frequency band and the digital signal frequency band, communication when connected to a digital line and communication when connected to an analog line. In either case, signal attenuation does not occur.
[0025]
The operation when the telephone line / doorphone switching adapter 1 of the present invention is connected to a digital line will be described below.
The switching unit 11 maintains the connection of the DSU 2 to the telephone line L side and can perform digital communication via the telephone line L. The intercom call control circuit 15 can detect a call from the doorphone 3 due to a voltage drop or the like, and can detect a call from the monitoring panel 4 or the collective entrance child device 5 by receiving a call signal through the control line L2. When the doorphone call control circuit 15 detects these calls, the control unit 10 switches the DSU 2 and the telephone line without switching the switching unit 11 if the connection to the digital line is set by a switch or the like. While the connection of L is maintained, the ringing tone generator 17 outputs a ringing tone such as “ping-pong” from the speaker SP. When the call button 18 is operated in response to this call, the call circuit 16 shifts to a call state with the door phone 3 or the like using the microphone MI and the speaker SP.
[0026]
When the adapter 1 is called through the telephone line L during the intercom call by the call circuit 16, the switching unit 11 maintains the connection on the telephone line L side. It is possible to detect and respond. The same applies when a call is made through the telephone line L while the adapter 1 is talking to the monitoring panel 4 or the collective entrance 5.
[0027]
As described above, if the adapter 1 has a call function, when a call is made from the door phone 3 when connected to the digital line, a ringing sound is generated by the ring tone generating unit 17 and the door phone by the call circuit 16 is generated. Calls can be made.
Next, another configuration of the telephone line / door phone switching adapter is shown in FIG.
This adapter 1A is different from the conventional configuration shown in FIG. 4 in that the telephone line L and the incoming call detection circuit 13 are connected between the telephone line L and the incoming call detection circuit 13 that detects a call signal transmitted through the telephone line L. The only difference is that a switch means 19 for disconnecting the connection with the switch 13 is provided.
[0028]
When the telephone line L is changed to a digital line, the switch means 19 disconnects the connection between the telephone line L and the incoming call detection circuit 13. As a result, when the telephone line L is changed to a digital line, the incoming call detection circuit 13 becomes an extra load and the signal waveform is not attenuated or distorted, so that normal communication can be performed.
When connected to the digital line, the incoming call detection circuit 13 for detecting the call signal (16 Hz) transmitted as an analog signal is not necessary, and the communication device prohibits a call with the door phone 3 side, and the adapter In 1A, since it is not necessary to detect a call signal transmitted as a digital signal, there is no problem even if the connection between the telephone line L and the incoming call detection circuit 13 is disconnected.
[0029]
When connected to the digital line, when a call is made through the telephone line L, communication is performed in the communication device, and when a call is made from the doorphone 3 side, a doorphone call is made by the microphone MI and the speaker SP of the adapter 1A.
On the other hand, when connecting to the analog line, the call means can be detected by the incoming call detection circuit 13 without disconnecting the connection between the telephone line L and the incoming call detection circuit 13 by the switch means 19. It operates in the same way as before.
[0030]
In the above, FIG. 1 shows the adapter 1 characterized by the external line use state detection circuit 12, and FIG. 3 shows the adapter 1A provided with the switch means 19, and these have been described separately. May have both at the same time.
[0031]
【The invention's effect】
As can be understood from the above description, according to the telephone line / doorphone switching adapter according to claim 1 or 2 of the present invention, the current detection circuit for detecting the use state of the telephone line is provided with a high-frequency signal. Therefore, even if the telephone line is changed to a digital line, it is not necessary to rewire and normal communication can be performed.
[0032]
In particular, in claim 1 , the current detection circuit can be simply configured with a coil and a capacitor. Further, in claim 2 , since the resonance frequency of the coil and the capacitor is set to a frequency other than the analog signal speech frequency band and the digital signal frequency band, communication when connected to a digital line and connection to an analog line There will be no hindrance to any of the communications.
[0033]
According to the telephone line / doorphone switching adapter according to claim 3 of the present invention, since the switch means for disconnecting the connection between the telephone line and the incoming call detection circuit is provided, when the telephone line is changed to a digital line, If the connection between the telephone line and the incoming call detection circuit is disconnected by the switch means, the incoming call detection circuit does not become an excessive load, the signal waveform is not attenuated or distorted, and normal communication can be performed.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an example of a configuration of a telephone line / doorphone switching adapter according to the present invention.
FIG. 2 is a diagram showing a relationship between a frequency and a resistance value by a telephone line / door phone switching adapter according to the present invention.
FIG. 3 is a block diagram showing an example of another configuration of the telephone line / door phone switching adapter of the present invention.
FIG. 4 is a block diagram showing an example of a configuration of a conventional telephone line / door phone switching adapter.
FIG. 5 is a diagram showing a relationship between a frequency and a resistance value by a conventional telephone line / door phone switching adapter.
[Explanation of symbols]
1, 1A Telephone line / door phone switching adapter 10 Control unit 11 Switching unit 12 External line use state detection circuit 13 Incoming call detection circuit 19 Switch means 2 DSU
3 Doorphone L Telephone line

Claims (3)

A telephone line that enables communication by a communication device by connecting a telephone line and a door phone installed at the entrance of a dwelling unit, connecting a communication device, and switching and connecting either the telephone line or the door phone. In the door / door phone switching adapter, the current detection circuit connected in series to the telephone line in order to detect the use state of the telephone line is configured to suppress an increase in resistance due to the passage of a high-frequency signal. ,
The telephone line / doorphone switching adapter , wherein the current detection circuit comprises a coil that is connected in series to the telephone line and detects a current, and a capacitor connected in parallel to the coil . 2. The telephone line / door phone switching adapter according to claim 1 , wherein the resonance frequency of the coil and the capacitor is set to a frequency other than a frequency band for analog signals and a frequency band for digital signals. A telephone line that enables communication by a communication device by connecting a telephone line and a door phone installed at the entrance of a dwelling unit, connecting a communication device, and switching and connecting either the telephone line or the door phone. / In the door phone switching adapter,
Switch means for disconnecting the connection between the telephone line and the incoming call detection circuit is provided between the telephone line and the incoming call detection circuit for detecting a call signal transmitted through the telephone line, and the telephone line is a digital line. In some cases, the telephone line / doorphone switching adapter is characterized in that the switch means disconnects the connection between the telephone line and the incoming call detection circuit .

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