JP2005229421A - Intercom system and signal transmitter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to easily and inexpensively change an existing intercom system exclusive for voice call to a video intercom system. <P>SOLUTION: In the system, which is provided with a complex entrance machine 12 installed at an entrance of a housing complex and a living room master machine 22 installed at each living room and controls a call between the complex entrance machine 12 and the living room master machine 22 by transmitting/receiving a control signal and a voice signal via a control trunk line 38 and a voice trunk line 32 by a standard controller 30, a camera 14 and a video controller 40 are installed on the side of the complex entrance machine 12, a living room monitor 24 is installed at each living room. When the system is changed to the video intercom system, a video signal from the video controller 40 is mixed with the control signal from the standard controller 30 by a mixer 50, transmitted to the control trunk line 38 and on the side of each living room, its transmitting signal is divided into the control signal and the video signal by a demultiplexer 51 and outputted to the living room master machine 22 and the living room monitor 24. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  INDUSTRIAL APPLICABILITY The present invention includes an intercom system that includes a front door unit and a room unit, and transmits a control signal, a voice signal, and the like for communication transmitted and received between these units via a transmission line, and the system. The present invention relates to a signal transmission device.

  Conventionally, in condominiums, apartments, and other apartment houses, collective entrance units have been installed at the common entrance of each unit, and a main unit has been installed in the living room of each unit. Or via a trunk line for transmitting audio signals, a visitor can selectively call a room base unit of a desired dwelling unit via a collective entrance, and the call can be sent via the room base unit. An intercom system that enables conversation with a resident who has responded is known.

In addition, in such intercom systems, a camera for capturing images of visitors is installed on the side of the collective entrance, and a display that displays the images captured by the camera is installed on the side of the living room. Also known is the so-called TV intercom system, which allows residents to visually check visitors by converting images captured by the camera into video signals for transmission and transmitting them to the display. (For example, see Patent Document 1, Patent Document 2, etc.).
JP 2002-158784 A JP 2003-178382 A

  By the way, in a conventional TV intercom system, transmission lines (voice trunk line, control trunk line) for transmitting voice signals and control signals for calls are used as transmission lines for transmitting video signals captured on the entrance door side to each dwelling unit. Apart from), a video trunk dedicated to video signal transmission was used.

  For this reason, in order to change an existing intercom system for voice calls that does not have a camera or display to a TV intercom system, simply change the collective entrance unit or room base unit to one with a camera or display. In addition, a video trunk line for transmitting video signals must be newly installed in the apartment building between the entrance hall and the main unit of each residence, which makes the change work extremely complicated and costly. There was a problem that it took. In some buildings, it is difficult to wire the video trunk line, and the existing intercom system cannot be changed to the TV intercom system.

  Such a problem occurs not only in an apartment house but also in a detached house when an existing intercom system dedicated to voice calls is changed to a TV intercom system.

  The present invention has been made in view of these problems, and is suitable for realizing an intercom system that can easily and inexpensively change an existing intercom system dedicated to voice calls to a TV intercom system, and the intercom system. An object of the present invention is to provide a simple signal transmission device.

  The intercom system according to claim 1, which has been made to achieve the above object, includes an entrance unit and a room unit, and the control unit transmits a control signal for call control in accordance with a command from the entrance unit. By transmitting to the room machine via the control trunk line, the call between the entrance machine and the room machine is controlled, and the call is transmitted and received between the door machine and the room machine under the call control. The voice signal is relayed through a voice trunk for voice signal transmission.

  On the entrance machine side, there are provided imaging means for imaging, video output means for converting a captured image obtained by the imaging means into a video signal for transmission, and a mixer. The video signal output from the video output means and the control signal output from the controller are mixed and output to the control trunk line.

  The room unit is provided with display means for displaying an image taken by the image pickup means and a duplexer, and the duplexer is a transmission signal transmitted from the entrance machine side via the control trunk line. Are separated into a control signal and a video signal, and the separated control signal and video signal are output to the room unit and the display unit, respectively.

  That is, in the intercom system according to claim 1, by using the mixer and the duplexer, the video signal picked up by the image pickup means provided on the entrance machine side and output from the video output means is controlled. The signal is transmitted to the display unit on the room unit side through the control trunk for signal transmission.

  Therefore, according to the intercom system of the present invention, when an existing intercom system dedicated to voice calls is changed to a TV intercom system, the video main line for video signal transmission is not wired in the home as in the prior art. Video signals can be transmitted using existing control trunk lines, mixers, and duplexers wired inside, enabling a TV intercom system to be realized extremely easily and at low cost. become.

  Next, in the intercom system according to claim 2, as with the intercom system according to claim 1, the intercom system includes an entrance unit and a room unit, and the control unit uses a control signal for call control in accordance with a command from the entrance unit. Is transmitted to the room machine via the control trunk line for control signal transmission, thereby controlling the call between the entrance machine and the room machine, and transmitting and receiving between the entrance machine and the room machine under the call control. The voice signal for call is relayed through the voice trunk for transmitting the voice signal.

  On the entrance machine side, there are provided imaging means for imaging, video output means for converting a captured image obtained by the imaging means into a video signal for transmission, and a mixer. The video signal output from the video output means and the audio signal output from the controller are mixed and output to the audio trunk line.

  The room unit is provided with a display unit for displaying an image captured by the imaging unit and a duplexer, and the duplexer is a transmission signal transmitted from the entrance unit via the voice trunk line. Are separated into an audio signal and a video signal, and the separated audio signal and video signal are output to the room unit and the display unit, respectively.

  That is, in the intercom system according to claim 2, by using the mixer and the duplexer, the video signal picked up by the image pickup means provided on the entrance machine side and output from the video output means is converted into a sound signal. The signal is transmitted to the display unit on the side of the room through the voice trunk for signal transmission.

  Therefore, according to the intercom system of the present invention, when an existing intercom system dedicated to voice calls is changed to a TV intercom system, the video main line for video signal transmission is not wired in the home as in the prior art. Video signals can be transmitted using existing voice trunk lines, mixers and duplexers that are wired inside, and a TV intercom system can be realized extremely easily and at low cost. It becomes possible.

  According to a third aspect of the present invention, the intercom system includes an entrance unit and a room unit, and the control unit sends a control signal for call control via a trunk for signal transmission in accordance with a command from the entrance unit. By transmitting to the machine, the call between the entrance machine and the room machine is controlled, and the voice signal for the call transmitted and received between the entrance machine and the room machine under the call control is controlled with the control signal. Relay through the same trunk line.

  On the entrance machine side, there are provided imaging means for imaging, video output means for converting a captured image obtained by the imaging means into a video signal for transmission, and a mixer. The video signal output from the video output means is mixed with the audio signal and control signal output from the controller, and output to the trunk line for signal transmission.

  The room unit is provided with display means for displaying a captured image by the image pickup means and a duplexer. The duplexer transmits the transmission signal transmitted from the entrance unit via the trunk line as an audio signal. The control signal and the video signal are separated, the separated audio signal and the control signal are output to the room unit, and the video signal is output to the display means.

  That is, in the interphone system according to claim 3, by using the mixer and the duplexer, the video signal picked up by the image pickup means provided on the entrance machine side and output from the video output means is converted into the audio signal. The signal and the control signal are transmitted to the display unit on the side of the room machine via the trunk for transmitting the control signal.

  Therefore, according to the intercom system of the present invention, when an existing intercom system dedicated to voice calls is changed to a TV intercom system, the video main line for video signal transmission is not wired in the home as in the prior art. All transmission signals including video signals can be transmitted using the existing trunk line, mixer and duplexer wired inside, making the TV intercom system extremely simple and low cost. Can be realized.

  As described above, in the intercom system of the present invention (claims 1 to 3), a control trunk for transmitting a control signal, a voice trunk for transmitting a voice signal, or a control signal and a voice signal are transmitted. Is used as a video trunk for video signal transmission, so that a TV intercom system can be constructed without wiring a video trunk dedicated to video signals. The intercom system according to any one of claims 1 to 3) may be an intercom system for a single-family house composed of an entrance machine and a single room machine. Alternatively, as described in claim 4, Installed in each dwelling unit, the controller calls one of the dwelling units installed in each dwelling unit by sending a control signal according to the command from the entrance machine, Call control is performed by transmitting and receiving control signals and audio signals to and from a specific room unit that has responded to the call, and the video signal is transmitted from the video output means to the specific room unit. Even an intercom system for an apartment house constructed as described above can be applied.

  In particular, if the present invention is applied to an intercom system for an apartment house, it is not necessary to wire a video trunk line for transmitting a video signal for each dwelling unit in the apartment house. can do.

  Conventionally, in a TV intercom system, there is known a system in which power is supplied from a front door side to display means installed in a room together with the room unit. When constructing such a TV intercom system using claim 4), as described in claim 5, the video output means is connected to the video signal for transmission generated from the captured image on the side of the room unit. The DC power supply voltage for operating the display means is configured to be superimposed and output, the mixer and the duplexer are configured to be able to input and output video signals superimposed with the DC power supply voltage, and the display means is configured to What is necessary is just to comprise so that it may receive and operate | move, receiving the DC power supply voltage transmitted from the entrance machine side with the signal.

On the other hand, the invention described in claim 6 relates to a signal transmission apparatus suitable for use as a mixer or duplexer in the intercom system described in claim 1 described above.
In this signal transmission device, two types of filters that selectively pass the control signal and the video signal, respectively, and one of the two types of filters, one signal input / output terminal of the filter that passes the control signal. Connected to the connected control signal input / output terminal, the video signal input / output terminal connected to one signal input / output terminal of the filter that similarly allows the video signal to pass, and the other signal input / output terminal of the two types of filters, respectively. And a transmission signal input / output terminal for inputting / outputting a transmission signal in which the control signal and the video signal are mixed.

  Therefore, according to the signal transmission device of the sixth aspect, if the control signal and the video signal are input to the control signal input / output terminal and the video signal input / output terminal, respectively, these signals are mixed and transmitted. It can function as a mixer that outputs from a signal input / output terminal. Conversely, if a transmission signal in which a control signal and a video signal are mixed is input to the transmission signal input / output terminal, this transmission signal is used as a control signal. Separated into video signals, each of these signals can be made to function as a demultiplexer that outputs from the control signal input / output terminal and the video signal input / output terminal.

Therefore, if the signal transmission apparatus according to claim 6 is used, the intercom system according to claim 1 can be easily constructed.
Next, the invention described in claim 7 relates to a signal transmission apparatus suitable for use as a mixer or a demultiplexer in the intercom system described in claim 2 described above.

  In this signal transmission device, two types of filters that selectively pass the audio signal and the video signal, respectively, and one of the two types of filters, one signal input / output terminal of the filter that passes the audio signal. Connected to the connected audio signal input / output terminal, the video signal input / output terminal connected to one signal input / output terminal of the filter that similarly allows the video signal to pass, and the other signal input / output terminal of the two types of filters, respectively. And a transmission signal input / output terminal for inputting / outputting a transmission signal in which an audio signal and a video signal are mixed.

  Therefore, according to the signal transmission device of the seventh aspect, if an audio signal and a video signal are input to the audio signal input / output terminal and the video signal input / output terminal, respectively, these signals are mixed and transmitted. It can function as a mixer that outputs from the signal input / output terminal. Conversely, if a transmission signal in which an audio signal and a video signal are mixed is input to the transmission signal input / output terminal, the transmission signal is converted into an audio signal. Separated into video signals, each of these signals can be made to function as a demultiplexer that outputs from the audio signal input / output terminal and the video signal input / output terminal.

Therefore, if the signal transmission device according to claim 7 is used, the intercom system according to claim 2 can be easily constructed.
Next, the invention according to claim 8 relates to a signal transmission apparatus suitable for use as a mixer or duplexer in the intercom system according to claim 3 described above.

  In this signal transmission device, three types of filters that selectively pass the audio signal, the control signal, and the video signal, respectively, and one of the three types of filters that passes the audio signal is input. An audio signal input / output terminal connected to the output terminal, a control signal input / output terminal connected to one signal input / output terminal of the filter that also passes the control signal, and one signal input of the filter that also passes the video signal. A video signal input / output terminal connected to the output terminal and a signal input / output terminal connected to the other signal input / output terminal of each of the three types of filters for inputting / outputting a transmission signal in which a control signal, an audio signal, and a video signal are mixed. And a transmission signal input / output terminal.

  Therefore, according to the signal transmission device of the eighth aspect, the audio signal, the control signal, and the video signal are respectively input to the audio signal input / output terminal, the control signal input / output terminal, and the video signal input / output terminal. If it is input, it can function as a mixer that mixes these signals and outputs them from the transmission signal input / output terminal. Conversely, the audio signal, control signal, and video signal are mixed at the transmission signal input / output terminal. If the transmission signal is input, the transmission signal is separated into an audio signal, a control signal, and a video signal, and these signals are divided into an audio signal input / output terminal, a control signal input / output terminal, and a video signal input / output terminal. Can function as a duplexer that outputs each of the signals.

Therefore, if the signal transmission apparatus according to claim 8 is used, the intercom system according to claim 3 can be easily constructed.
As described above, according to the signal transmission device of the sixth to eighth aspects, the interphone system of the present invention described above can be easily constructed. In constructing the intercom system, as described in claim 9, each filter is configured to block the passage of the DC signal component, and between the video signal input / output terminal and the transmission signal input / output terminal. It is sufficient to provide a direct-current pass filter that selectively passes only the direct-current signal component.

  In other words, if the signal transmission device is configured in this way, the DC power supply voltage superimposed on the video signal (or to be superimposed on the video signal) is transferred from the video signal input / output terminal to the transmission signal input / output via the DC pass filter. 6. The interphone system according to claim 5, wherein the intercom system can be passed through a terminal (or the opposite direction) and is configured to supply power from the entrance unit to the display means in the living room. It can be built.

  In the intercom system of the present invention (claims 1 to 5), a control trunk for transmitting control signals, a voice trunk for transmitting voice signals, or a trunk for transmitting control signals and voice signals are used. However, if the transmission impedance of these signal transmission trunks differs from the input / output impedance of the equipment on the entrance unit side or the room unit side, the signal quality is set to a predetermined level. It is necessary to match the impedance of the signal transmission device used as a mixer or a demultiplexer in order to keep each device within the range and stably operate each device.

  For this purpose, a transformer for impedance matching is provided between at least one of the plurality of filters constituting the signal transmission device and a signal input / output terminal connected to the filter. It is preferable that impedance is matched by using this transformer.

Embodiments of the present invention will be described below with reference to the drawings.
[First embodiment]
FIG. 1 is a block diagram showing a schematic configuration of an intercom system according to a first embodiment to which the present invention is applied.

  The intercom system of the present embodiment is a so-called collective intercom system constructed in a collective housing composed of a plurality of dwelling units, and as shown in FIG. 1, a collective entrance machine 10 with a camera installed at a common entrance of the collective housing, Each dwelling unit includes a room machine 20 installed in the room.

  Here, the camera-equipped collective entrance machine 10 includes a collective entrance machine 12 having a microphone and a speaker for calling, an operation panel for calling a dwelling unit, and the like, and an imaging means for taking an image of the entrance (that is, a visitor). A collective entrance camera 14 is provided, and the room unit 20 includes a base unit 22 having a receiver for receiving a call from the collective entrance machine 12 or a not-shown entrance handset, and a collective entrance camera. And a living room monitor 24 as a display means for displaying the image captured at 14.

  The collective entrance machine 12 is connected to a standard controller 30, and the standard controller 30 specifies information for specifying a specific dwelling unit via the operation panel of the collective entrance machine 12 (specifically, a room number or the like). Is entered, the room unit 20 of the dwelling unit corresponding to the specified information is called. After that, when there is a response from the room unit 20, a call between the room unit 20 and the collective entrance machine 12 is permitted, The voice signal for a call transmitted and received between the entrance machine 12 and the room machine 20 is relayed.

  The collective entrance camera 14 is connected to a video controller 40 serving as a video output means. The video controller 40 transmits a video signal (for example, FM modulation) of an image captured by the collective entrance camera 14. Signal), and the video signal is transmitted to the room unit 29 that is making a call with the collective entrance 12.

  Next, in the apartment house, a voice trunk line 32 for transmitting voice signals for communication between the standard controller 30 and the room master unit 22 in each room, and the standard controller 30 and each room. A control trunk line 38 for transmitting a control signal for call control with the inside room master unit 22 is wired.

  The voice trunk line 32 and the control trunk line 38 are provided with a branching unit 42 for each dwelling unit. The branching unit 42 and the voice line 44 or the control line 48 of each dwelling unit are used to connect each of the living rooms. Audio signals and control signals can be input and output to the room master unit 22.

  On the other hand, a video line for transmitting a video signal output from the video controller 40 is not wired in the apartment house, but a mixer 50 is provided at the end of the control trunk line 38 on the side of the collective entrance 10 with a camera. Are input to the mixer 50 via the video line 36 and the control line 34, respectively, from the video signal output from the video controller 40 and the control signal output from the standard controller 30. These signals are mixed by the mixer 50, and the mixed transmission signal is transmitted to each room via a control trunk line 38 wired in the apartment house.

  In addition, the control signal 48 branched from the control trunk line 38 via the branching unit 42 separates the transmission signal transmitted from the camera-equipped entrance door 10 side via the control trunk line 38 into a control signal and a video signal. A branching filter 51 is connected to output the separated control signal and video signal to the living room master unit 22 and the living room monitor 24 via the control line 48 and the video line 49, respectively.

Note that the voice trunk line 32, the control trunk line 38, the voice line 44, the control lines 34 and 48, and the video lines 36 and 49 are each composed of a twisted pair line.
The video controller 40 has a built-in monitor power supply 41 for supplying power to the room monitor 24 in each room, and the video controller 40 generates a video signal generated from an image captured by the collective entrance camera 14. Is output on the power supply DC voltage generated by the monitor power supply 41 (video signal + DC voltage).

  For this reason, the mixer 50, the branching device 42, and the branching filter 51 are configured to be able to pass a DC power supply, and the room monitor 24 in each room receives the DC voltage output from the video controller 40. Operate.

  In the intercom system of the present embodiment configured as described above, an audio signal, a control signal, a video signal, and a DC voltage for driving the room monitor 24 (between the collective entrance machine 10 with the camera and the room unit 20). In this embodiment, as shown in FIG. 2A, a so-called baseband sound having a frequency of several hundred Hz to several kHz (for example, 300 Hz to 5 kHz) is included in the sound signal. A control signal that is FSK modulated using two waves between 50 kHz and 100 kHz (for example, two carrier waves of 50 kHz and 70 kHz) is used for the control signal, and the above-mentioned is used for the video signal. Thus, an FM-modulated video signal of several MHz to several tens of MHz (for example, 1 MHz to 15 MHz) is used.

  2B, among these signals, the control signal, the video signal, and the direct current voltage (DC) for feeding are transmitted via the control trunk line 38, and the voice signal is sent to the voice trunk line 32. Is transmitted through.

  Therefore, according to the intercom system of this embodiment, when an existing collective intercom system dedicated to voice calls is changed to a TV intercom system, a video trunk for video signal transmission is wired in the collective housing as in the past. In addition, the video signal can be transmitted using the existing control trunk line 38, the mixer 50, and the duplexer 51 wired in the apartment house. This can be realized easily and at low cost.

Next, FIG. 3 is a configuration diagram showing a configuration of a signal transmission device used as the mixer 50 or the demultiplexer 51 in the intercom system of the present embodiment.
As shown in FIG. 3, this signal transmission device (mixer 50 or duplexer 51) is connected to the branch terminal of the control trunk line 38 or branching unit 42, and transmits and receives transmission signals to and from the control trunk line 38. A transmission signal input / output terminal t1, a control signal input / output terminal t2 for inputting / outputting a control signal connected to the control line 34 or 48, and a video signal or DC voltage connected to the video line 36 or 49. A video signal input / output terminal t3 for inputting / outputting, and a low-pass filter whose cutoff frequency is set to, for example, 100 kHz in order to cut off the video signal and pass only the control signal (hereinafter, the low-pass filter is referred to as LPF). 52, a high-pass filter whose cutoff frequency is set to 1 MHz, for example, to cut off the control signal and allow only the video signal to pass (hereinafter referred to as HPF). And wherein to) 54, it is provided.

  One signal input / output terminal of the LPF 52 is connected to a control signal input / output terminal t2 via a DC signal component (DC component) cut capacitor C2 and an impedance matching transformer TR2. The signal input / output terminal is connected to the video signal input / output terminal t3 via the DC component cutting capacitor C3 and the impedance matching transformer TR3.

  The other signal input / output terminal of the LPF 52 and the other signal input / output terminal of the HPF 54 are connected to each other, and the connection point is transmitted via an impedance matching transformer TR1 and a DC component cutting capacitor C1. It is connected to the signal input / output terminal t1.

  Each of the signal input / output terminals t1 to t3 is composed of a pair of terminals in order to be connected to the twisted pair wire, but constitutes a transmission signal input / output terminal t1 and a video signal input / output terminal t3. One terminal is connected to coils L1 and L3 for dropping the DC component to the ground, and the other terminal is cut to selectively pass only the DC component (ie, DC voltage). They are connected to each other via an LPF 56 whose off frequency is set to 40 kHz, for example. The LPF 56 corresponds to a DC pass filter of the present invention, and includes a coil L01 and a capacitor C01.

  The signal transmission device of FIG. 3 configured as described above mixes these signals when the control signal and the video signal are input to the control signal input / output terminal t2 and the video signal input / output terminal t3, respectively. The mixed signal can be made to function as a mixer 50 that outputs the mixed signal from the transmission signal input / output terminal t1, and conversely, if a transmission signal in which the control signal and the video signal are mixed is input to the transmission signal input / output terminal t1. The transmission signal can be separated into a control signal and a video signal, and function as a branching filter 51 that outputs these signals from the control signal input / output terminal t2 and the video signal input / output terminal t3.

  Further, since the transmission signal input / output terminal t1 and the video signal input / output terminal t3 are connected via the LPF 56 for allowing a DC component to pass therethrough, a DC voltage superimposed on the video signal is applied to these terminals t1-t3. It can be passed in between.

Therefore, by using the signal transmission device shown in FIG. 3 as the mixer 50 or the duplexer 51, the intercom system of the present embodiment shown in FIG. 1 can be easily constructed.
[Second Embodiment]
Next, FIG. 4 is a block diagram showing a schematic configuration of the intercom system of the second embodiment to which the present invention is applied.

  The intercom system of the present embodiment is a so-called collective intercom system constructed in a collective housing, like the intercom system of the first embodiment, and is basically configured similarly to the intercom system of the first embodiment. .

  Therefore, in the following description, in the intercom system according to the present embodiment, portions different from the intercom system according to the first embodiment will be described in detail, and description of portions similar to those of the first embodiment will be omitted.

  As shown in FIG. 4, in the intercom system of the present embodiment, the control signal input / output terminal of the standard controller 30 is directly connected to the control trunk line 38 wired in the apartment house. 30 audio signal input / output terminals are connected to the mixer 80 via an audio line 35.

  The mixer 80 mixes the video signal output from the video controller 40 and the audio signal output from the standard controller 30 and outputs the mixed audio signal to the audio trunk line 32 wired in the apartment house. The voice signal from the room unit 20 input via the trunk line 32 is output to the standard controller 30 via the voice line 35.

  Further, the room master unit 22 is connected to the control line 48 branched from the control trunk line 38 via the branching unit 42, and the branching unit 81 is connected to the branching terminal from the voice trunk line 32 of the branching unit 42. Is provided.

  The duplexer 81 separates the transmission signal input from the branch terminal of the branching device 42 into an audio signal and a video signal (specifically, a video signal + DC voltage), and the separated audio signal is connected to the audio line 44. And the video signal (specifically, the video signal + DC voltage) is output to the living room monitor 24 via the video line 49, and further from the living room master 22 via the audio line 44. The output voice signal is output to the voice trunk line 32 via the branching unit 42.

  That is, as shown in FIG. 2C, the intercom system of the present embodiment transmits the video signal, the audio signal, and the feeding direct current voltage (DC) via the audio trunk line 32. Transmission is performed via the control trunk line 38.

  Therefore, according to the intercom system of this embodiment, when an existing collective intercom system dedicated to voice calls is changed to a TV intercom system, a video trunk for video signal transmission is wired in the collective housing as in the past. The video signal can be transmitted using the existing voice trunk line 32, the mixer 80 and the duplexer 81 wired in the apartment house, and the television intercom system is installed in the apartment house. This can be realized easily and at low cost.

Next, FIG. 5 is a configuration diagram showing a configuration of a signal transmission device used as the mixer 80 or the demultiplexer 81 in the intercom system of the present embodiment.
As shown in FIG. 5, this signal transmission device (mixer 80 or duplexer 81) is connected to the voice trunk line 32 or the branch terminal of the branching device 42, and transmits / receives transmission signals to / from the voice trunk line 32. A transmission signal input / output terminal t4 for connecting to the audio line 35 or 44, an audio signal input / output terminal t5 for inputting / outputting an audio signal, and a video signal 36 or 49 for connecting the video signal and DC voltage. A video signal input / output terminal t3 for inputting / outputting, an LPF 58 whose cutoff frequency is set to, for example, 10 kHz in order to cut off the video signal and allow only the audio signal to pass through, and an audio signal to cut off only the video signal. An HPF 54 having a cut-off frequency set to 1 MHz, for example, is provided for the passage.

  One signal input / output terminal of the LPF 58 is connected to the audio signal input / output terminal t5 via the DC component cutting capacitor C5 and the impedance matching transformer TR5, and one signal input / output terminal of the HPF 54 is The DC component cutting capacitor C3 and the impedance matching transformer TR3 are connected to the video signal input / output terminal t3.

  The other signal input / output terminal of the LPF 58 and the other signal input / output terminal of the HPF 54 are connected to each other, and the connection point is transmitted via the impedance matching transformer TR4 and the DC component cutting capacitor C4. It is connected to the signal input / output terminal t4.

  Each of the signal input / output terminals t3 to t5 is composed of a pair of terminals in order to connect to the twisted pair wire, but constitutes a transmission signal input / output terminal t4 and a video signal input / output terminal t3. One terminal is connected to coils L4 and L3 for dropping the DC component to the ground, and the other terminal is cut in order to selectively pass only the DC component (ie, DC voltage). They are connected to each other via an LPF 60 whose off frequency is set to, for example, 300 Hz. Note that the LPF 60 corresponds to a DC pass filter of the present invention, and includes a coil L02 and a capacitor C02.

  In the signal transmission device of FIG. 5 configured as described above, if an audio signal and a video signal are input to the audio signal input / output terminal t5 and the video signal input / output terminal t3, respectively, these signals are mixed, The mixed signal can be made to function as a mixer 80 that outputs the transmission signal from the transmission signal input / output terminal t4. Conversely, if a transmission signal in which an audio signal and a video signal are mixed is input to the transmission signal input / output terminal t4. The transmission signal can be separated into an audio signal and a video signal, and function as the branching filter 51 that outputs these signals from the audio signal input / output terminal t5 and the video signal input / output terminal t3.

  Further, since the transmission signal input / output terminal t4 and the video signal input / output terminal t3 are connected via the LPF 60 for selectively passing only the DC component (DC voltage), they are superimposed on the video signal. A DC voltage can be passed between these terminals t4-t3.

Therefore, by using the signal transmission device shown in FIG. 5 as the mixer 80 or the demultiplexer 81, the intercom system of the present embodiment shown in FIG. 4 can be easily constructed.
[Third embodiment]
Next, FIG. 6 is a block diagram showing a schematic configuration of an intercom system of a third embodiment to which the present invention is applied.

  The intercom system of the present embodiment is a so-called collective intercom system constructed in a collective housing, similar to the intercom systems of the first and second embodiments, and basically the same as the intercom system of the first embodiment. It is configured.

  Therefore, in the following description, in the intercom system of the present embodiment, portions different from the intercom systems of the first embodiment and the second embodiment will be described in detail, and the description of the same portions as the above embodiments will be omitted. To do.

  As shown in FIG. 6, in the intercom system of the present embodiment, the control signal input / output terminal and the audio signal input / output terminal of the standard controller 30 are connected via the control line 34 and the audio line 35, respectively. It is connected to the mixer 90. Further, the video signal output terminal of the video controller 40 is also connected to the mixer 90 via the video line 36.

  The mixer 90 mixes the audio signal and the control signal output from the standard controller 30 with the video signal output from the video controller 40 (specifically, the video signal + DC voltage), so that the inside of the apartment The voice signal and the control signal from the side of the living room 20 input via the trunk line 33 are output to the signal transmission trunk line 33 wired to the standard controller via the control line 34 and the voice line 35. Output to 30.

  Further, a branching filter 91 is connected to the branch line branched from the main line 33 via the branching unit 43. The demultiplexer 91 separates the transmission signal input from the branch terminal of the branching device 43 into an audio signal, a control signal, and a video signal (specifically, a video signal + DC voltage), and the separated audio signal and The control signal is output to the room master unit 22 via the audio line 44 and the control line 48, and the video signal (specifically, the video signal + DC voltage) is output to the room monitor 24 via the video line 49. The voice signal and the control signal output from the master unit 22 via the voice line 44 and the control line 48 are output to the trunk line 33 via the branching unit 43.

  That is, the intercom system according to the present embodiment transmits all the transmission signals (that is, the audio signal, the control signal, the video signal, and the direct-current voltage (DC) for feeding) shown in FIG. The data is transmitted through one trunk line 33 made up of twisted pair wires wired to each other.

  Therefore, according to the intercom system of this embodiment, when an existing collective intercom system dedicated to voice calls is changed to a TV intercom system, a video trunk for video signal transmission is wired in the collective housing as in the past. The video signal can be transmitted using one trunk line 33, the mixer 90, and the duplexer 91 wired in the apartment house. It can be realized easily and at low cost.

Next, FIG. 7 is a block diagram showing a configuration of a signal transmission device used as the mixer 90 or the branching filter 91 in the intercom system of the present embodiment.
As shown in FIG. 7, this signal transmission device (mixer 90 or duplexer 91) is connected to the branch terminal of the trunk line 33 or the branching unit 43 to input / output transmission signals to / from the trunk line 33. A transmission signal input / output terminal t6, an audio signal input / output terminal t5 for inputting / outputting an audio signal connected to the audio line 35 or 44, and an input / output for a control signal connected to the control line 34 or 48 A control signal input / output terminal t2 and a video signal input / output terminal t3 for connecting to the video line 36 or 49 and inputting / outputting a video signal and a DC voltage are provided.

  Further, the signal transmission device includes an LPF 58 whose cutoff frequency is set to, for example, 10 kHz in order to cut off the control signal and the video signal and allow only the audio signal to pass, and the control signal and the video signal by cutting off the voice signal. Among the set HPF 62 whose cutoff frequency is set to 50 kHz, for example, and a mixed signal of the control signal and the video signal passing through the HPF 62, and only the control signal is passed. In order to achieve this, an LPF 52 whose cutoff frequency is set to 100 kHz, for example, and an HPF 54 whose cutoff frequency is set to 1 MHz for example to cut off the control signal and pass only the video signal are provided. .

  One signal input / output terminal of the LPF 58 is connected to the audio signal input / output terminal t5 via the DC component cutting capacitor C5 and the impedance matching transformer TR5, and one signal input / output terminal of the LPF 52 is The DC signal cut capacitor C2 and the impedance matching transformer TR2 are connected to the control signal input / output terminal t2, and one signal input / output terminal of the HPF 54 is impedance matched with the DC component cut capacitor C3. It is connected to the video signal input / output terminal t3 through the transformer TR3.

  The other signal input / output terminal of the LPF 58 and one signal input / output terminal of the HPF 62 are connected to each other, and the connection point is transmitted via the impedance matching transformer TR6 and the DC component cutting capacitor C6. The other signal input / output terminal of the HPF 62 is connected to the signal input / output terminal t6, and the other signal input / output terminal of the LPF 52 and the HPF 54 is connected to the DC component cutting capacitor C1 and the impedance matching transformer TR1. It is connected to the.

  Each of the signal input / output terminals t2, t3, t5, and t6 is composed of a pair of terminals in order to connect to the twisted pair wire, but the transmission signal input / output terminal t6 and the video signal input / output terminal. Coils L6 and L3 for dropping the DC component to the ground are connected to one terminal constituting t3, respectively, and the other terminal selectively allows only the DC component (that is, DC voltage) to pass therethrough. Therefore, they are connected to each other via the LPF 60 whose cutoff frequency is set to, for example, 300 Hz. The LPF 60 corresponds to the DC pass filter of the present invention, as shown in FIG. 5, and includes a coil L02 and a capacitor C02.

  The signal transmission apparatus of FIG. 7 configured as described above has an audio signal, a control signal, and a video signal at the audio signal input / output terminal t5, the control signal input / output terminal t2, and the video signal input / output terminal t3, respectively. Can be made to function as a mixer 90 that mixes these signals and outputs the mixed signal from the transmission signal input / output terminal t6, and conversely, the transmission signal input / output terminal t6 When a transmission signal in which a control signal and a video signal are mixed is input, the transmission signal is separated into an audio signal, a control signal, and a video signal, and these signals are input to an audio signal input / output terminal t5 and a control signal input. It can function as a duplexer 91 that outputs from the output terminal t2 and the video signal input / output terminal t3.

  Further, since the transmission signal input / output terminal t6 and the video signal input / output terminal t3 are connected via the LPF 60 for selectively passing only the DC component (DC voltage), they are superimposed on the video signal. A DC voltage can be passed between these terminals t6-t3.

Therefore, by using the signal transmission device shown in FIG. 7 as the mixer 90 or the branching filter 91, the intercom system of the present embodiment shown in FIG. 6 can be easily constructed.
[Modification]
Although the three embodiments to which the present invention is applied have been described above, the present invention is not limited to the above-described embodiments, and various modes can be adopted within the technical scope of the present invention.

  For example, in each of the above embodiments, in the signal transmission device used as the mixer 50, 80, 90 or the demultiplexer 51, 81, 91, signal input / output terminals t1 to t6 to which various transmission lines composed of twisted pair wires are connected. The internal circuit and the internal circuit have been described as being connected via impedance matching transformers TR1 to TR6. However, when the impedances of the transmission paths of the signals are all matched, the transmission path is simply adjusted by the filter. It is not always necessary to provide the impedance matching transformers TR1 to TR6.

  Specifically, for example, in the signal transmission device shown in FIG. 3, as shown in FIG. 8, the LPF 52 is composed of a capacitor C7 and four coils L7, and the HPF 54 is composed of a coil L8 and four capacitors C8. The LPF 52 and the HPF 54 may be connected to the signal input / output terminals t1 to t3 without using the transformers TR1 to TR3.

  For example, in the signal transmission device shown in FIG. 7, as shown in FIG. 9, the LPF 52 is composed of a capacitor C7 and four coils L7, and the HPF 54 is composed of a coil L8 and four capacitors C8. The LPF 58 is composed of the capacitor C9 and the four coils L9, the HPF 62 is composed of the coil L10 and the four capacitors C10, and these filters 52, 54, 58, and 62 are respectively connected to the transformers TR1 to TR3 or TR5 and TR6. May be connected to the signal input / output terminals t2, t3, t5, and t6.

  Next, in each of the above embodiments, the video controller 40 is provided with the monitor power source 41, and the room monitor 24 in each room is supplied with power from the monitor power source 41. A monitor power supply may be provided.

  Furthermore, in each of the above-described embodiments, the case where the present invention is applied to an intercom system for an apartment house has been described. However, the present invention relates to a detached entrance machine corresponding to the collective entrance machine 10 with a camera and one room machine. Even if it is the intercom system for single-family houses comprised from 20, if it applies similarly to said each Example, the effect similar to said each Example can be acquired.

It is a block diagram which shows schematic structure of the intercom system of 1st Example. It is explanatory drawing explaining the trunk line used in order to transmit the type of the transmission signal transmitted with the intercom system of an Example, and each signal in 1st Example and 2nd Example. It is a block diagram showing the structure of the signal transmission apparatus suitable for using it as a mixer or a splitter in the intercom system of 1st Example. It is a block diagram which shows schematic structure of the intercom system of 2nd Example. It is a block diagram showing the structure of the signal transmission apparatus suitable for using as a mixer or a splitter in the intercom system of 2nd Example. It is a block diagram which shows schematic structure of the intercom system of 3rd Example. It is a block diagram showing the structure of the signal transmission apparatus suitable for using as a mixer or a splitter in the intercom system of 3rd Example. It is explanatory drawing showing the modification of the signal transmission apparatus shown in FIG. It is explanatory drawing showing the modification of the signal transmission apparatus shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Collective entrance machine with a camera, 12 ... Collective entrance machine, 14 ... Collective entrance camera, 20 ... Living room machine, 22 ... Living room main machine, 24 ... Living room monitor, 30 ... Standard control machine, 32 ... Voice trunk line, 33 ... Trunk line , 34, 48 ... control line, 35, 44 ... audio line, 36, 49 ... video line, 38 ... control trunk line, 40 ... video controller, 41 ... monitor power supply, 42, 43 ... branching device, 50, 80, 90 ... Mixer, 51, 81, 91 ... Splitter, C01, C02, C1 to C10 ... Capacitor, L01, L02, L1 to L10 ... Coil, TR1 to TR6 ... Transformer, 52, 56, 58 ... LPF (Low-pass filter) , 54, 62... HPF (High Pass Filter), t1, t4, t6... Transmission signal input / output terminal, t2... Control signal input / output terminal, t3.

Claims (10)

An entrance machine installed at the entrance of the house,
A room machine installed in a residential room;
In accordance with a command from the entrance unit, a call between the entrance unit and the office unit is performed by transmitting and receiving a control signal for communication control with the office unit via a control trunk for transmitting a control signal. A controller that relays a voice signal for a call transmitted and received between the entrance unit and the room unit under the call control via a voice trunk for transmitting a voice signal;
In the intercom system with
On the entrance machine side,
Imaging means for imaging,
Video output means for converting a captured image by the imaging means into a video signal for transmission and outputting;
A mixer that mixes the video signal output from the video output means and the control signal output from the controller and outputs the mixed signal to the control trunk line;
Provided,
To the room machine side,
Display means for displaying a captured image by the imaging means;
A transmission signal transmitted from the entrance unit via the control trunk line is separated into a control signal and a video signal, and the separated control signal and the video signal are output to the room unit and the display unit, respectively. Waver,
An intercom system characterized by providing. An entrance machine installed at the entrance of the house,
A room machine installed in a residential room;
In accordance with a command from the entrance unit, a call between the entrance unit and the office unit is performed by transmitting and receiving a control signal for communication control with the office unit via a control trunk for transmitting a control signal. And a controller that relays a voice signal for a call transmitted and received between the entrance unit and the room unit under the call control via a voice trunk for transmitting a voice signal;
In the intercom system with
On the entrance machine side,
Imaging means for imaging,
Video output means for converting a captured image by the imaging means into a video signal for transmission and outputting;
A mixer that mixes the video signal output from the video output means and the audio signal output from the controller and outputs the mixed signal to the audio trunk line;
Provided,
To the room machine side,
Display means for displaying a captured image by the imaging means;
A transmission signal transmitted from the entrance unit via the voice trunk line is separated into an audio signal and a video signal, and the separated audio signal and the video signal are output to the room unit and the display unit, respectively. Waver,
An intercom system characterized by providing. An entrance machine installed at the entrance of the house,
A room machine installed in a residential room;
In accordance with a command from the entrance unit, a call between the entrance unit and the office unit is performed by transmitting and receiving a control signal for communication control with the office unit via a control trunk for transmitting a control signal. And a controller that relays a voice signal for a call transmitted and received between the entrance unit and the room unit via the trunk line under the call control,
In the intercom system with
On the entrance machine side,
Imaging means for imaging,
Video output means for converting a captured image by the imaging means into a video signal for transmission and outputting;
A mixer that mixes the video signal output from the video output means with the audio signal and control signal output from the controller and outputs the mixed signal to the trunk line;
Provided,
To the room machine side,
Display means for displaying a captured image by the imaging means;
The transmission signal transmitted from the entrance unit via the trunk line is separated into an audio signal, a control signal, and a video signal, and the separated audio signal and control signal are output to the room unit, and the video A duplexer for outputting a signal to the display means;
An intercom system characterized by providing. The housing is a housing complex composed of a plurality of dwelling units,
The room machine is installed for each of the plurality of dwelling units,
The controller calls one of the room units installed for each of the plurality of dwelling units by transmitting a control signal in accordance with a command from the entrance unit, and then the specific room unit that has responded to the call and 2. The call control is performed by transmitting and receiving the control signal and the audio signal between each other, and the video signal is transmitted from the video output means to the specific room unit. The intercom system according to claim 3. The video output means is configured to superimpose and output a DC power supply voltage for operating the display means on the room unit side to the video signal for transmission generated from the captured image,
The mixer and duplexer are configured to be able to input and output a video signal on which the DC power supply voltage is superimposed,
The interphone system according to any one of claims 1 to 4, wherein the display means is configured to operate by receiving a DC power supply voltage transmitted from an entrance machine side together with the video signal. A signal transmission device used as the mixer or the duplexer in the intercom system according to claim 1,
Two types of filters that selectively pass the control signal and the video signal,
A control signal input / output terminal connected to one signal input / output terminal of the filter that allows the control signal to pass among the two types of filters;
A video signal input / output terminal connected to one signal input / output terminal of the filter that allows the video signal to pass, of the two types of filters;
A transmission signal input / output terminal connected to the other signal input / output ends of the two types of filters, for inputting / outputting a transmission signal in which the control signal and the video signal are mixed;
A signal transmission device comprising: A signal transmission device used as the mixer or the duplexer in the intercom system according to claim 2,
Two types of filters that selectively pass the audio signal and the video signal,
An audio signal input / output terminal connected to one signal input / output terminal of the filter that allows the audio signal to pass, of the two types of filters;
A video signal input / output terminal connected to one signal input / output terminal of a filter that allows the video signal to pass through, of the two types of filters;
A transmission signal input / output terminal connected to each of the other signal input / output terminals of the two types of filters, for inputting / outputting a transmission signal in which the audio signal and the video signal are mixed;
A signal transmission device comprising: A signal transmission device used as the mixer or the duplexer in the intercom system according to claim 3,
Three types of filters that selectively pass the audio signal, the control signal, and the video signal,
An audio signal input / output terminal connected to one signal input / output terminal of the filter that allows the audio signal to pass among the three types of filters;
A control signal input / output terminal connected to one signal input / output terminal of the filter that allows the control signal to pass among the three types of filters;
A video signal input / output terminal connected to one signal input / output terminal of the filter that allows the video signal to pass among the three types of filters;
A transmission signal input / output terminal connected to each of the other signal input / output terminals of the three types of filters, for inputting / outputting a transmission signal in which the control signal, the audio signal, and the video signal are mixed;
A signal transmission device comprising: Each of the filters is configured to block passage of a DC signal component;
9. A DC pass filter that selectively passes only a DC signal component is provided between the video signal input / output terminal and the transmission signal input / output terminal. Or a signal transmission device.   The signal according to claim 6, wherein at least one of the plurality of filters includes a transformer for impedance matching between a signal input / output terminal connected to the filter. Transmission equipment.

Images