JPH0383442A - Interphone for multiple dwelling house - Google Patents

Abstract

PURPOSE:To shorten the full length of wiring and to facilitate wiring by executing cascade connection to branchers equipped with input terminals, sending terminals and branching terminals, connecting the input terminal to the branching terminal in each brancher at standby time and connecting the input terminal to the branching terminal in any one of the branchers at the time of a call. CONSTITUTION:The cascade connection is executed to plural branchers B1, B2,... equipped with input terminals 51, sending terminals 52 and branching terminals 53 so that the sending terminal can be connected to the input terminal of the other brancher. Then, by connecting the input terminal of the brancher in the first step, for which the cascade connection is executed, to a transmission line to be connected to an entrance equipment and connecting the input terminal of the brancher to the sending terminal at the standby time, a trunk line is constituted from the entrance equipment through all the branchers to a terminating means. By switching and connecting the input terminal of any one of the branchers to the branching terminal at the time of the call, any one of inhouse equipments is connected through a transmission line (l) to one entrance equipment and the other inhouse equipments are separated. Controllers C1, C2,... control the branchers B1, B2,... corresponding to a selecting signal or a canceling signal to be applied from an external part through the transmission line or an exclusive signal line.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an intercom for apartment complexes, which can be used between an entrance device installed in a common entrance or a manager's room and a housing device installed in each dwelling unit. This device is suitable for making phone calls.

[Prior Art] A schematic configuration of a conventional TV-equipped intercom is shown in FIG. 4. When a visitor operates a call switch 24 provided on an entrance device G, a resistor R3 is connected in parallel to an impedance Z1. Then, the ringing signal is transmitted to the dwelling unit J, and the ringing tone is emitted from the ringing speaker 3 of the dwelling unit J. When the resident responds to this ringing tone by pressing the response switch 4, the television camera 21 installed in the entrance device G is connected to the power supply line 11.
Power is supplied to the , and the video signal is sent to the coaxial cable i.

The image is transmitted to the housing unit J via the , and the image is displayed on the monitor TV 1. In addition, the audio signal from the handset 2 of the dwelling device J is transmitted to the entrance device G via the signal line &2 for communication, and the resident's voice is output from the speaker 22 through the audio transformer 29 of the entrance device G. . On the other hand, the visitor's voice signal inputted by the microphone 23 of the entrance device G passes through the audio amplifier 26, the coupling capacitor 27, the bridge circuit 28, and the audio transformer 29, and then is sent to the dwelling unit J via the signal line 12 for communication. The visitor's voice signal is transmitted and the visitor's voice signal is output from the handset 2 of the dwelling unit J. This allows the two visitors to talk to each other and the resident, and also allows the resident to see the visitor.

It should be noted that an emergency lamp 25 is connected to the entrance device G via a resistor R2, and serves as a head for reporting an abnormality in the house to the entrance via an emergency reporting line 14.

In this conventional example, in order to connect the residential unit J and the entrance unit G, a coaxial cable e0 for video signal transmission and a power line 15 are used.
A four-core cable is used: a signal line 12 for calls and calls, a ground line l, and an emergency call line i. For this reason, the wiring of transmission lines is complicated, and if, for example, only 2-core or 4-core cables for intercom calls are installed during construction, the wiring must be redone when additional TV cameras are installed. There was a problem.

[Tsurugai 1] Figures 5(a) and 5(b) show a schematic configuration of another conventional example. This system consists of a housing unit J with a monitor TV 1 installed inside the housing unit, and a housing unit J installed at the entrance.

It is constructed by combining an entrance device G having a television camera 21 placed thereon, and both are connected by a dedicated transmission line l such as a coaxial cable. There is a housing unit J on the entrance unit G side.
Power is supplied from the side, and video, audio, and control signals are multiplexed and the necessary information is communicated.

To explain the more specific configuration, the dwelling unit J is the entrance unit G.
F of the calling signal transmitted in response to the operation of the calling switch 24 of the entrance device G.
A ringing detection circuit 19 that demodulates the M modulated wave, a ringing tone generation circuit 20 that amplifies the demodulated ringing tone and makes the ringing tone sound from the ringing speaker 3, a voice modulation circuit 17 that modulates the voice signal with FM, and an entrance device G. An audio demodulation circuit 13 that demodulates the transmitted FM modulated signal to extract an audio signal, a handset 2 that includes a microphone and a speaker for communications, an audio amplifier 14, 15 that constitutes a communications circuit that includes the handset 2, and a sidetone prevention circuit 16. , a video signal output circuit 11 that takes out the video signal sent out from the entrance device G and outputs it to the monitor TV l, and an FM modulation signal output from the audio modulation circuit 17 through the bandpass filter 18. The FM modulation signal sent out from the door unit G is outputted to the audio demodulation circuit 13 via the bandpass filter 12, the video signal sent out from the entrance unit G is outputted to the video signal output circuit 11 via the video filter 10, Furthermore, the power superimposing circuit 8
A balanced input/output circuit 9 is provided for transmitting the supply voltage to the entrance device G. The audio modulation circuit 17 is configured to perform FM modulation on the transmitted audio signal from the handset 2 and send it out to the transmission line l through the balanced input/output circuit 9. The configuration is such that the FM modulated signal is demodulated and the voice of the entrance device G is output from the handset 2. Further, the video signal transmitted from the entrance device G is outputted to the monitor television 1 after being amplified by the video signal output circuit 11 via the balanced input/output circuit 9 and the video filter 10. A transmission line short-circuit protection circuit 6 and an open detection circuit 7 are added to the power supply superimposition circuit 8.

Moreover, when the response switch 4 is operated, the control circuit 5 is operated, the power supply superimposing circuit 8 is operated, and power is supplied to the entrance device G.

On the other hand, the entrance device G includes an audio demodulation circuit 38 that demodulates the FM modulated signal sent from the housing device J and extracts an audio signal;
Audio modulation circuit 40 that modulates the audio signal from the microphone 23
, a calling signal generating circuit 43 that generates a calling signal in response to the operation of the calling switch 24, an operating state determining circuit 42 that determines the operating state and can generate a calling signal if the call is not in progress, and a voice modulation circuit An FM modulated signal outputted from the circuit 40 via the bandpass filter 41, an FM modulated signal outputted from the calling signal generation circuit 43, and an FM modulated signal outputted from the television camera 21 to the video filter 30 and the video signal output circuit 31.
A balanced input/output circuit 32 inputs a video signal outputted through the transmission line 1 and sends a multiplexed transmission signal to the transmission line 2, and outputs an FM modulated signal to the audio demodulation circuit 38 via a bandpass filter 37; A non-polarizing circuit 33 for non-polarizing the connection with the entrance device G, and a balanced input/output circuit 3 from the modulated signal sent from the housing unit J via the transmission line l.
The power supply separation circuit 34 is provided for separating the power supply of the entrance device G via the power supply terminal 2. The power supply voltage separated by the power supply separation circuit 34 is used as a camera power supply and a circuit power supply via a power switch circuit 35 and a shunt regulator 36. The audio modulation circuit 40 FM-modulates the audio signal input from the microphone 23 and amplified by the audio amplifier 26 and sends it to the housing unit J via the balanced input/output circuit 32. It is configured to demodulate the FM modulated signal from the circuit 32, amplify it in the audio amplifier 39, and output audio from the speaker 22.

In this intercom system, dwelling unit J and entrance unit G are
are connected by a pair of transmission lines L made of coaxial cables, etc., and video, audio, and other control signals necessary for information communication are multiplex transmitted between the two via this transmission line I11. There is.

FIG. 6 shows the frequency division state of the signal transmitted via the transmission line 1 in this system.

As shown in the figure, the FM modulated wave of the audio signal sent from the housing device J to the entrance device G is transmitted at the first carrier frequency,
The FM modulated wave of the voice signal sent from the entrance device G to the dwelling unit J is transmitted at the second carrier frequency, and the FM modulated wave of the calling signal is transmitted at the third carrier frequency. The frequency is set to be higher than the video signal frequency band of the television camera that is transmitted over the band.

Note that the power supply voltage is superimposed as a DC component, and these are multiplexed and transmitted via a dedicated transmission It11.

By the way, when such a system is used in an apartment complex with a large number of housing units, it is necessary to use multiple units in order to make a call between the common entrance (or manager's room) and one of the housing units. For example, a method that requires switching the voice line by some means is conceivable.For example, a method may be considered in which control is performed so that only the unit in the dwelling unit that is on the phone is able to transmit the frequency assigned for transmitting the audio signal.In this method, each dwelling unit Since the equipment is always connected to the common entrance equipment, it is necessary to use a dedicated branch or distributor to match the impedance of the transmission line.On the other hand, only the selected residential equipment It is also possible to use a method in which the unit is switched and connected to the entrance unit, and other household appliances are disconnected from the entrance unit.In this method (see Japanese Patent Application No. 01-88678), a branch for impedance matching of the transmission line or Instead of a distributor, it is sufficient to install a transmission line switch.This switch is wired with a transmission line that connects to the entrance unit and a transmission line that connects to each of the multiple housing units, and connects any one of the housing units. This is to switch and connect the device to the entrance device.

[Problem to be Solved by the Invention] However, when a star wiring switch like the one described above is installed between multiple housing units, the switch There was a problem in that the wiring from the to each unit became long, and the total wiring length became long. Furthermore, since a large number of transmission lines are concentrated in one switch, the wiring becomes complicated and wiring errors are likely to occur during construction.

The present invention has been made in view of the above points, and its object is to reduce the total wiring length in an intercom for apartment complexes that selectively connects one of a plurality of dwelling units to an entrance unit. The goal is to shorten the length and simplify wiring.

[Means for Solving the Problems] In order to solve the above-mentioned problems, in the intercom for apartment complexes according to the present invention, as shown in FIGS. + J 21 J 31・
In an intercom that multiplex transmits at least an audio signal and a video signal between ... using a pair of transmission lines 1, a plurality of branchers B having an input terminal 51, a sending terminal 52, and at least one branch terminal 53.

B2. B,... are connected in cascade so that the feed terminal is connected to the input terminal of the other branch, and the input terminal of the cascaded first-stage branch is connected to the transmission line connected to the entrance switch, Connect the feed terminal of the final stage of the cascaded turnout to the termination means, connect the branch terminals of multiple turnouts to the transmission lines that connect to different housing units, and send the input terminal of the turnout during standby. The present invention is characterized by the provision of a controller C6C2+Ci . . . which connects to the terminal and switches and connects the input terminal of any one of the branching devices to the branching terminal in accordance with a selection signal given from the outside during a call.

Here, the controllers C, , C, , C, .
, B 3 , . . , the controller C, .
The selection signal or cancellation signal given to C7°C1, . . . may be transmitted via a signal line different from the transmission line, or may be multiplexed via the transmission line.

Note that the terminating means connected to the feed terminal of the cascade-connected final stage branch may be a housing unit or may be a terminating resistor.

[Function] In this way, in the present invention, a plurality of branches B + , B 2 , B 3 , . The terminals are connected in cascade so that they are connected to the input terminals of other turnouts, and the input terminal of the cascaded first-stage turnout is connected to the transmission line leading to the entrance switch, and when on standby, as shown in Figure 2. Since the input terminal of the turnout is connected to the feed terminal, a main line can be constructed from the entryway through all the turnouts to the termination means. When making a call, the input terminal of any one branch switch is switched to the branch terminal as shown in Figure 3, so that any one unit connects to the entrance unit via the transmission line l. 1 and disconnected from other residential units, there is no risk of deterioration in call quality due to impedance mismatch or the like. Furthermore, at the end of a call, by switching and connecting the input terminal of the turnout to the sending terminal, it is possible to reconfigure the trunk line from the entryway through all the turnouts to the terminating means, as shown in Figure 2. . This turnout B,,B2. Controllers C+, C2, C3, . . . for controlling the switching operations of B, .
. is preferably for each branch B, , B2 . The branchers B, , B2 . . . are installed in the vicinity of the branchers B, . Controls the switching operation of B□...

[Example] FIG. 1 is a block diagram of one embodiment of the present invention.

First, the entrance device G consists of a doorbell D with a camera and a dwelling unit selection unit S. The configuration of the camera-equipped door phone D is as follows:
The configuration is the same as that of the entrance device G in the conventional television intercom shown in the figure, and the video signal and the audio signal are multiplexed and placed on the transmission line l. In order to reduce power consumption, power is not supplied to this camera-equipped door phone D when it is on standby (when not talking), and power is supplied from repeater R via transmission line l only when it is in operation. It is composed of The dwelling unit selection unit S selects a plurality of dwelling units Jl, J2. J3
．． ... is a device for selecting one from the entrance device G side, and is equipped with a numeric keypad T for selection. The selection signal of the dwelling unit at the doorway G is DTMF (DouL+le Modulated
It is transmitted using a T one Frequency) signal.

This selection signal may be superimposed with the audio from the entrance device G (No. 3), or may be transmitted on a different carrier wave from the audio signal of the entrance device G, or the DTMF signal may be transmitted as a separate signal. The operating power of the dwelling unit selection unit S may be superimposed on the signal line and supplied from the repeater R, but in this embodiment, the operating power of the dwelling unit selection unit S is transmitted by a door phone D with a camera. It is supplied independently.

Housing equipment J l * J 2 r J 3 +... is,
It has the same tank bottom as the conventional housing unit J shown in FIG. In the configuration shown in FIG. 1, two residential units J2 are provided, and one of them is connected to the turnout B2 by a switch K. In addition, each housing unit J I
+J 2. J.sub.z, .

The repeater R transmits the selection signal generated by the dwelling unit selection unit S in the entrance device G to the controller C+ via a dedicated signal line.
, C2, C3, . . . Based on this selection signal, the controllers C, , C, , C, . . .
l, B2. B1. Controls the switching operation of... Also,
The repeater R is the transmission &! connected to the entrance device G. 1 is relayed to the input terminal 51 of the first branch B.

The branch B has an input terminal 51, a feed terminal 52, and a branch terminal 53.The input terminal 51 has a feed terminal 52.
Alternatively, it is selectively connected to one of the branch terminals 53. Other turnout B2. Bi... also has a similar configuration. The feed terminal of the first turnout B is connected to the input terminal of the second turnout B2, and the feed terminal of the second turnout Bt is connected to the input terminal of the third turnout B3. The feed terminal of the third branch B3 is connected to an input terminal of a fourth branch (not shown) or to a termination means.

The terminal means is transmission! It may be the terminal impedance equivalent to the characteristic impedance of lβ, or it may be the same as the characteristic impedance of
It may be.

The switching operations of the switches B + , B z , and B 3 will be described below with reference to FIGS. 2 and 3. first,
During standby, as shown in FIG. 2, each turnout B7.
B2.

The input terminal 51 of B is connected to the sending terminal 52,
As a result, from the entrance device G to the repeater R1 branch B + ,
B2, Bs, the trunk line to the residential unit J (or the terminating means) is constructed. At the time of a call, the controllers C+, C2, C3 are connected from the entrance unit G via the repeater R.
A selection signal is transmitted to the Now, if a selection signal for selecting the housing unit J2 is given to the controllers C,,C2,C, only the branch B2 connects the input terminal 51 to the branch terminal 53 as shown in FIG. As a result, the switching operation is performed so that the switching operation is performed such that the switching operation is performed from the entrance device G to the repeater R1 and the branching device B +
, B2, and a transmission line to the housing unit J is constructed.

The repeater R is equipped with a voltage discrimination circuit for monitoring the voltage of the transmission line connected to the first branch B, detects the voltage level of the DC component on this transmission line, and depending on the detection result, Distinguish between the operating state and non-operating state of the housing unit. After the branch B2 performs a switching operation and the dwelling unit J2 is connected to the repeater R, a dwelling unit calling signal is transmitted from the entrance unit G or the repeater R to the dwelling unit J2. As this calling signal, as explained in the conventional example, a carrier wave with a special frequency may be transmitted, or the calling signal may be transmitted by lowering the transmission line voltage below a certain value, or by short-circuiting the transmission line. On the side of the dwelling unit J2, the unit J2 receives the call signal and starts operating, and the circuit for power supply operates to increase the voltage level of the DC component of the transmission line l. As mentioned above, the residential unit supplies a low DC voltage to the transmission line l even in the standby state, but in the operating state, the DC voltage of the transmission line l is set higher than in the standby state. . In the repeater R, the level of this DC voltage is monitored by a voltage discrimination circuit to detect the start of operation of the dwelling unit. When the start of operation of the dwelling device is detected, the power superimposing circuit of the repeater R operates, and power is supplied to the camera-equipped door intercom D of the entrance device G. Therefore, when power is supplied to the camera-equipped door phone D, the dwelling unit is always connected normally and starts operating normally. Therefore, a situation in which the FM modulated wave from the dwelling unit is not supplied to the FM audio demodulation circuit in the camera-equipped door phone D does not occur, and abnormal noise does not occur.

Here, while the first dwelling unit is being selected and called using the entrance unit G, inconvenience may occur if another dwelling unit is called. In other words, if you call a second unit while the first unit is calling, multiple units may respond at the same time, but since the entrance unit can only talk to one unit, Therefore, in this embodiment, after the first dwelling unit is selected and called, selection of another dwelling unit is not accepted until the end of the call. There is. Specifically, repeater R
Even if the repeater R receives a selection signal from the dwelling unit selection unit S, it does not relay it to the controllers C+, C2, and C3 until the voltage discrimination circuit detects the end of the call.

When the call ends, the DC voltage of the transmission line 1 is set to a standby voltage on the residential unit side, so the level of the DC voltage of the transmission line 1 decreases. Therefore, the repeater R monitors the level of the DC voltage of the transmission line l and detects a fall in the voltage, thereby canceling the selection of the dwelling unit. Specifically, a release signal is sent from the repeater R to the controllers C+, C2, C3, and all branchers B, , B2 . B, is reset to the standby connection state shown in FIG. However, in this embodiment, since an FM audio demodulation circuit is used in the camera-equipped door intercom D, the controllers C+, Cz,
Before sending the release signal to C), the operation of the power superimposing circuit in repeater R is stopped, and the power to camera-equipped door phone D in entrance device G is cut off first, thereby preventing the generation of abnormal noise. .

By the way, there may be a vacant line in the transmission line from the turnout B2 to the housing unit J2, or there may be a break in the transmission line leading to the housing unit J2.
If the voltage of the first branch B1 is not normal, the voltage of the transmission line from the first branch B1 to the repeater R will not reach the specified voltage even after connecting the branch B2 to the residential unit J2 side. In device R, if the voltage of transmission line l does not reach the specified voltage even after a certain period of time (for example, 1 second) has passed after switch B2 is operated by the selection signal, a release signal is forcibly generated. Then, return all the turnouts B, , B2.B to the state shown in Figure 2, and in this case,
Since the voltage rise of the transmission line connected to 2 is not detected, the power superimposition circuit of repeater R is connected to door phone D with camera.
does not start power supply operation.

In other words, in this embodiment, the power of the camera-equipped doorbell D in the entrance device G is not turned on unless the dwelling device is properly connected and has started operating normally.
lr! j.I'm doing it.

The above operation has been explained for the case where the housing unit J2 is selected, but it goes without saying that the same operation occurs when the housing unit J or J is selected. The number is not limited to the examples,
Can be any function.

In addition, the operating power for the turnouts B + , B 2 , B y and the controllers C + , C2, and Cx is supplied from either the entrance switch G, the repeater R1 switch K, or the housing unit J, , J, , J. In addition, a dedicated power supply line may be provided to supply operating power, or a power supply superimposed on the transmission line may be used, and normally open contacts, normally closed contacts, and common contacts may be used. If you use a relay circuit with this as a switch for a branch, connect the normally open contact to the branch terminal, connect the normally closed contact to the feed terminal, and connect the common terminal to the input terminal,
By simply cutting off the power supply to the relay circuit, the common contact returns to a normally closed contact, so it is possible to easily return to the standby state in which the input terminal is connected to the sending terminal.

In the above embodiment, a dedicated signal line is provided to transmit the selection signal or the cancellation signal to the controllers C+, C2, and C:l, but multiplex transmission may also be performed using the transmission line l. In this case, a fourth carrier frequency may be added to the multiplexed transmission signal shown in FIG. 6, and the selection signal or cancellation signal may be transmitted by modulating this fourth carrier frequency.

In the embodiment, a repeater R is provided between the entrance device G and the first branch 2"wB, but if the function of this repeater R is included in the entrance device G, the repeater R can be omitted. good.

[Effects of the Invention] As described above, in the present invention, turnouts having an input terminal, a feed terminal, and a branch terminal are connected in cascade so that the feed terminal is connected to the input terminal of another turnout. , the input terminal of each turnout is connected to the sending terminal when on standby, and the input terminal of one turnout is connected to the branch terminal when talking, so the entrance terminal connected to the input terminal of the first turnout It is possible to configure a transmission line from the unit to the residential unit connected to the branch terminal of any branch switch, and at this time, other residential units are disconnected from the transmission line, so good transmission quality can be obtained. Moreover, since each branch can be connected by a feed wiring, the total wiring length can be shortened and wiring can be made easier.

[Brief explanation of drawings]

Fig. 1 is a block diagram of an embodiment of the present invention, Figs. 2 and 3 are block diagrams for explaining the operation of the same as above, Fig. 4 is a schematic tank bottom diagram of a conventional example, and Fig. 5 (,) and (b) are block diagrams of a dwelling device and an entrance device in other conventional examples, respectively, and FIG. 6 is an explanatory diagram showing an example of frequency division on a transmission line used in the same. B, , B, , B is a turnout, C+, C2, C3 are controllers, G is a doorway, J l+J 2. J 3. J< is a housing unit, and l is a transmission line.

Claims (4)

[Claims] (1) In an intercom that multiplex transmits at least an audio signal and a video signal between a doorway unit and a dwelling unit using a pair of transmission lines, a plurality of branchers each having an input terminal, a sending terminal, and at least one branch terminal. are connected in cascade so that the feed terminal is connected to the input terminal of the other branch, and the input terminal of the cascaded first stage branch is connected to the transmission line leading to the entrance switch, and the cascaded terminal is connected to the input terminal of the other branch. Connect the feed terminal of the turnout to the terminating means, connect the branch terminals of multiple turnouts to the transmission lines that connect to different residential units, and connect the input terminal of the turnout to the feed terminal during standby to make a call. An intercom for an apartment complex, characterized in that it is provided with a controller that switches and connects the input terminal of any one of the branch terminals to the branch terminal depending on a selection signal given from the outside. (2) The intercom for an apartment complex according to claim 1, wherein the controller includes means for switching and connecting the input terminal of the branch to the sending terminal in response to a release signal given from the outside at the end of the call. (3) The intercom for an apartment complex according to claim 1 or 2, wherein the selection signal or cancellation signal given to the controller is transmitted via a signal line different from the transmission line. (4) The intercom for apartment complexes according to claim 1 or 2, wherein the selection signal or cancellation signal given to the controller is multiplex transmitted via the transmission line.