JP2001045469A - Video interphone system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an excellent video interphone system to which a plurality of video output devices can be connected and which can arrange the devices at any place on the system. SOLUTION: This video interphone system is provided with a doorphone slave unit 6 with a camera, an interphone master unit 1 with a monitor television set connected through a pair-wire signal line L and interphone sub master units 2 to 4 with a monitor television set connected to the unit 1 through the line L, the unit 1 and the units 2 to 4 are provided with high impedance video output circuits 1-1 to 4-4, and also, an indoor camera 5 having a high impedance video output can be connected to the line L.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a door phone slave unit,
The present invention relates to a television intercom system including an intercom master unit and an intercom sub master unit.

[0002]

2. Description of the Related Art Conventionally, television intercom systems have been widely used in ordinary households. Such a system has a configuration in which one intercom master unit with a camera is connected to one intercom master unit with a monitor TV, and power is supplied from the master unit to the slave unit to enable bidirectional communication. The audio signal can be transmitted, and the video signal captured by the slave camera is transmitted to the master.

In addition, in the case where the interphone sub master units 2 and 3 with a monitor television are additionally connected to the above-mentioned system, a configuration as shown in FIG. 6 is obtained, and power is supplied from the interphone master unit 1 to the slave unit 6. A bidirectional audio signal can be transmitted between the handset 6 and the base unit 1 or between the handset 6 and the intercom sub-base units 2 and 3, and a video signal captured by the camera of the handset 6 Is transmitted to the base unit 1 and the sub-base units 2 and 3. In this system, the master unit 1 and the subsidiary master units 2
Each of 3 transmits a control signal for notifying the other that it has answered the call from the handset 6.

[0004] When receiving power, the slave unit 6 drives a camera circuit (not shown) to transmit a captured image to the multiplex transmission line L. In the intercom master unit 1 and the intercom sub master units 2 and 3, the video demodulation circuits 2-3 and 3-3 display the received video on the monitor televisions M1, M2 and 3 and respond by operating the talk buttons B1, B2 and 3. For example, a call circuit switch (not shown) is turned on, and the call circuit (not shown) enables an interphone call with the call circuit of the slave unit 6. At this time, of the intercom master device 1 or the intercom sub master devices 2 and 3, the call button B
Either one of B1, B2, and B3 responds and transmits a control signal to the other by a control signal transmission circuit (not shown). In the intercom master unit 1 or the intercom sub master units 2 and 3 receiving the control signal by the control signal receiving circuit, the operation of the monitor televisions M1, M2 and M3 shown in FIG. The message is displayed and the call is prohibited while the call circuit remains off. In the intercom master 1, even if the control signal is received from the intercom sub-master 6, the power supply from the power supply circuit is continued in order to maintain the call in the interphone sub-master 3.

Now, the operation of the video circuit will be described. First, as shown in FIG.
Receives, modulates the video signal to the indoor line L through the modulation circuit 1-2, and sends it out. Here, intercom master unit 1
Of the indoor line L (for example, R1 // R2
= 100Ω). Next, the intercom sub master units 2 and 3 have impedance circuits 2-1 and 3-1 that are higher than the characteristic impedance of the indoor line L, so that the video signal from the intercom master unit 1 is not attenuated. The video signal is input to a video demodulation circuit 2-
The signal is demodulated by 3, 3-3, and an image is displayed on monitor televisions M2, M3 shown in FIG. 6 through TV circuits 2-4, 3-4.

[0006]

However, in the above-mentioned conventional TV intercom system, since only one intercom master unit is used as a video output device for the image from the slave unit, the video output from another place is required. There is a problem that it cannot be transmitted to the indoor line, and furthermore, the connection point in the system of the intercom master unit has been determined, and it cannot be freely moved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to connect a plurality of video output devices and to dispose those devices anywhere on the system. A video intercom system.

[0008]

According to the first aspect of the present invention, there is provided an intercom base unit with a camera, an intercom master unit with a monitor television connected via a two-wire signal line,
A TV intercom sub-master unit with a monitor TV connected to the master unit via a two-wire signal line, wherein the monitor TV interphone master unit and the monitor TV interphone sub-master unit are A high-impedance video output circuit is provided, and an indoor camera having a high-impedance video output can be connected to the two-wire signal line.

According to the second aspect of the present invention, the first aspect is provided.
In the invention described above, the intercom master unit with monitor television and the intercom master unit with monitor television each have an imaging unit for deriving a video signal of a subject and a video signal derived from the imaging unit are modulated at different frequencies. First and second modulating means, and transmitting a video carrier modulated by the modulating means to a two-wire signal line, and corresponding to a video carrier derived from another interphone via the two-wire signal line. And a first and second video demodulation means for individually demodulating the video and video data.

[0010]

1 and 2 show a first embodiment of a television intercom system according to the present invention.
With reference to FIGS. 3 to 5 for the second embodiment,
Each will be described in detail.

[First Embodiment] FIG. 1 is a block diagram showing an example of the internal configuration of a television intercom system, and FIG. 2 is a diagram schematically showing a video signal high impedance circuit.

As in the conventional example shown in FIG. 6 described above, the television intercom system of the present invention is a sub-master unit with a monitor television connected to a door phone slave unit 2 with a camera via a two-wire signal line L. 3 and an interphone master unit 1 with a monitor television connected to the interphone sub master unit 3 via a two-wire signal line L. That is, the present invention can be configured by additionally connecting (adding) one sub master unit 3 to a system including one master unit 1 and one door phone slave unit 6.

When there is a call from the slave unit 6, the intercom master unit 1 starts supplying power to the slave unit 6, so that the video signal photographed by the camera of the slave unit 6 is transmitted to the interphone master unit 1 and the interphone sub master unit 3. Transmitted. When the base unit 1 responds, bidirectional transmission of audio signals between the slave unit 6 and the intercom base unit 1 becomes possible. At this time, a control signal is sent from intercom master 1 to intercom sub-master 3. On the other hand, when the intercom secondary master unit 3 responds, the slave unit 2
And the intercom master unit 1 is disconnected, and the sub master unit 3
Then, the power supply to the slave unit 6 is started, and the two-way transmission of the audio signal between the slave unit 6 and the intercom secondary master unit 3 becomes possible. Output.

Now, the operation of the video circuit will be described. As shown in FIG. 1, first, the video signal from the camera of the slave unit 6 is received by the intercom master 1, and the video signal is transmitted through a two-wire signal line. The video signal is modulated to the indoor line L by the video modulation circuit 1-2 and transmitted through the high impedance circuit 1-1 having an impedance higher than the characteristic impedance of the indoor line L. Similarly, the interphone sub master units 2, 3, and 4 also have high impedance circuits 2-1 3-1 and 4-1 higher than the characteristic impedance of the indoor line L, thereby attenuating the video signal from the intercom master unit 1. Video signal is input to the TV circuit 2-4, and the video signal is demodulated by the video demodulation circuits 2-3, 3-3, and 4-3.
Monitor TV M2, M3, M4 through 3-4, 4-4
Project the image to

The high impedance circuits 1-1 and 1-2 of the intercom master unit 1 and the intercom sub master units 2, 3, and 4
As shown in FIG. 2, -1, 3-1 and 4-1 are provided with a video signal high impedance transformer 1-1 and a video modulation circuit 1-2.
And a video demodulation circuit 1-3 so that the video signal has a high impedance.

The indoor camera 5 has an imaging circuit 5-5, a video modulation circuit 5-3 and a high impedance circuit 5-1.
Is almost the same as the operation of the video signal from the camera of
Here, it is omitted.

The characteristic impedance of the indoor line L is maintained by connecting the terminating resistors R2 and R1 (for example, R1 // R2 = 100Ω) of the intercom sub master units 3 and 4, which are far-end devices of the indoor line L. Can be.

Thus, a plurality of video output devices such as an intercom master unit and an indoor camera can be connected, and the video output devices can be installed at any positions on the indoor line.

[Second Embodiment] The difference between the first embodiment and the first embodiment is that the intercom according to the present embodiment has no distinction between the intercom master unit and the intercom sub-master unit, and the interphones 1, 2, and 3 are different. It is connected via a two-wire signal line L, and each intercom has a simultaneous call button and an individual call button. However, at this time, although not shown, the slave 6 may be connected to any of the intercoms.

Next, the operation of this system will be described with reference to FIG. 1) When the simultaneous call button of the intercom 1 is pressed In the intercom 1, when the camera switch KSW is turned on, the camera 1-70 operates, and the SW1 is connected to the frequency A modulation circuit 1-20 side. That is, the video signal from the camera 1-70 is modulated at the frequency A, and the high impedance circuit 1-70 is modulated.
10 to the indoor line L. Further, SW2 is connected to the frequency B demodulation circuit 1-50 side. That is, a video signal modulated at the frequency B is prepared. here,
Monitor 1-6 with TV switch TVSW off
0 is OFF.

The operations of the interphones 2 and 3 are as follows. First, when a simultaneous call command from the intercom 1 is received by the command transmission / reception circuit 1-80, the television switch TVSW is turned on, and the monitor 1-60 is turned on. Further, SW2 is connected to the frequency A demodulation circuit 1-40 side. That is, the video signal modulated by the frequency A coming from the intercom 1 is demodulated and displayed on the monitor 1-60.
Subsequently, SW1 connects to the frequency B modulation circuit 1-30, but the camera switch KSW remains OFF. The reason is that when the camera switch KSW is turned on, the video signals of the interphones 2 and 3 are modulated at the frequency B and mixed in the indoor line L.

When the talk button of the intercom 2 is pressed, the intercom 2 transmits a talk command from the command transmitting / receiving circuit 1-80 and turns on the camera switch KSW. That is, the camera 1-70 operates, and the video signal of the intercom 2 is modulated at the frequency B and transmitted to the indoor line L.

The intercom 3 receives the call command, turns off the TV switch TVSW, turns off the monitor 1-60, and recognizes that another person is talking.

The intercom 1 receives the call command and turns on the television switch TVSW. That is, the video signal modulated at the frequency B coming from the intercom 2 is demodulated and displayed on the monitor 1-60. Here, intercom 1
Remembers that the simultaneous call was made, and when receiving the call command, it recognizes it as a 1: 1 call.

To summarize the above: The called device operates the camera and modulates at the frequency A. -The called device operates the TV, demodulates it at frequency A, and displays it on the TV. When the called device presses the talk button, the called device operates the camera and modulates at the frequency B. The called device operates the monitor, demodulates it at the frequency B, and displays it on the monitor. 2) When the individual call button is pressed Basically, this is the same as when the general call button is pressed. The device that has not been called does not operate because it recognizes that another person is talking.

[0026] Thereby, it is possible to make a call while watching the video in a two-way manner with the interphones 1: 1.

[0027]

According to the first aspect of the present invention, it is possible to connect a plurality of video output devices such as an intercom master unit and an indoor camera, and it is possible to install the video output devices at any location in the indoor line.

According to the second aspect of the present invention, in addition to the effect of the first aspect of the present invention, a further advantage is provided that two-way intercoms can make a call while watching images with each other in a two-way manner. Play.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing a first embodiment of a television intercom system according to the present invention.

FIG. 2 is a diagram schematically showing the video signal high impedance circuit.

FIG. 3 is a system diagram showing a second embodiment of a television intercom system according to the present invention.

FIG. 4 is a schematic diagram of an intercom of the television intercom system.

FIG. 5 is an internal circuit block diagram of the intercom of the television intercom system.

FIG. 6 is a diagram showing a configuration of a conventional television intercom system.

FIG. 7 is an internal circuit block diagram of a conventional television intercom system.

[Explanation of symbols]

1 Intercom master 1-1,2-1,3-1,4-1 High impedance circuit 1-2 Video modulator 1-3 Video demodulator 2,3,4 Interphone secondary master 2-3-3-3 , 4-3 Video demodulation circuit 2-4, 3-4, 4-4 TV circuit 5 Indoor camera 5-1 High impedance circuit 5-3 Video modulation circuit 5-5 Image pickup circuit 6 Door phone handset 1, 2, 3 Interphone 1-10 High impedance circuit 1-20 Modulation circuit 1-30 Modulation circuit 1-40 Demodulation circuit 1-50 Frequency B demodulation circuit 1-60 Monitor 1-70 Camera 1-80 Command transmission / reception circuit B1, B2, B3 Call Button KSW Camera switch L Indoor line M1, M2M3, M4 Monitor TV R2, R1 Termination resistor TVSW TV switch

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5C054 AA02 BA02 CC03 DA03 DA08 EA01 EA03 EA05 EG02 EG08 FA00 HA22 5K038 AA03 CC00 DD15 DD23 EE08

Claims (2)

[Claims] 1. An intercom unit with a camera, an intercom master unit with a monitor TV connected via a two-wire signal line, and an interphone with a monitor TV connected to the master unit via a two-wire signal line A television intercom system, comprising: a sub master unit; and a high-impedance video output circuit provided in the interphone master unit with monitor television and the intercom sub master unit with monitor television, and an indoor camera having a high impedance video output. Can be connected to the two-wire signal line. 2. The intercom master unit with monitor television and the intercom master unit with monitor television each have an imaging unit for deriving a video signal of a subject and a video signal derived from the imaging unit are modulated at different frequencies. First
And a second modulating means, and transmitting the video carrier modulated by the modulating means to a two-wire signal line, and corresponding to the video carrier derived from another interphone via the two-wire signal line. 2. The television intercom system according to claim 1, wherein said television intercom system includes first and second video demodulation means for individually demodulating, and has a configuration in which a two-way telephone call and a video image can be confirmed.