JPH06303327A - Video doorphone system - Google Patents

Abstract

PURPOSE:To facilitate the extension construction of an indoor master machine and to eliminate necessity to provide an adapter for extension or the indoor master machine for extension which configuration is different from that of an indoor master machine for single station. CONSTITUTION:This system is provided with an entrance slave machine SQ provided with a camera 5 for picking up the image of a visitor and plural indoor master machine AM and BM provided with a television monitor 25 and a transmitter/receiver 31. The plural indoor master machine are respectively provided with off-hook detection circuits 33 for detecting the off-hook of the transmitter/receiver, reset signal sending circuits 35 to send reset signals to the other indoor master machine corresponding to the operations of the off-hook detection circuits and video signal cut-off circuits 24 for cutting off video signals to be outputted to the television monitor corresponding to the reset signals outputted from the reset signal sending circuits.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a TV intercom apparatus, and more particularly, to a TV that can be expanded by using an indoor master apparatus having the same structure when adding an indoor master apparatus to a single station type TV intercom apparatus. It is related to the doorphone device.

[0002]

2. Description of the Related Art Conventionally, there has been known a single station type TV intercom system in which a video signal from an entrance slave unit is monitored by a TV monitor of an indoor master unit and a call can be made between them. In this TV intercom device, an adapter-type TV intercom device shown in FIG. 6 is known to enable the indoor master unit to respond at two places (JP-A-3-83443). This TV intercom device is an entrance cordless handset 61 provided with a camera eye 1, a speaker 2, a microphone 3 and a call button 4.
And an indoor master device switching adapter 62 connected to the entrance slave device 61 with a cable L ₃ , and an indoor master device 63 branch-connected to the indoor master device switching adapter 62 with indoor master device cables L ₄ and L _5. , 64, and when the call button 4 of the entrance slave unit 61 is pressed, a call signal is sent to the indoor master units 63 and 64 via the indoor master unit switching adapter 62, and the television monitors 67 and 67, respectively. To be displayed. Therefore, for example, when the handset 65 is off-hook by the indoor base unit 63, the indoor base unit switching adapter 62 operates, the TV monitor 67 of the indoor base unit 64 is blanked, and the indoor base unit 63 and the entrance slave unit 61 are separated from each other. A call path is formed by.

In order to enable the indoor master unit to respond at two places, a dedicated extension type TV intercom system shown in FIG. 7 is known. This TV intercom device is composed of an entrance slave device 71, an indoor master device 72, and an additional indoor master device 73.
The entrance slave device 71 and the indoor master device 72 are connected by a cable L ₆ , and the indoor master device 72 and the additional indoor master device 73 are connected by a cable L ₇ . When the call button 4 of the entrance slave device 71 is pressed, the indoor master device 72 detects a call signal. Next, since the detected call signal is also sent to the additional indoor master device 73, the ringers of the indoor master device 72 and the additional indoor master device 73 ring,
Images are displayed on the respective television monitors 76, 76. Therefore, for example, if the handset 75 of the indoor base unit 72 is off-hook,
A signal notifying that the handset 75 of the indoor master device 72 is off-hook is sent to the additional indoor master device 73, and the television monitor 76 of the additional indoor master device 73 is blanked. In this state,
A call path is formed between the indoor master device 72 and the entrance slave device 71.

[0004]

In the TV intercom apparatus in which such an indoor master device is added, the adapter type has a drawback that the wiring must be changed significantly in order to provide the indoor master device switching adapter 62. In the case of the dedicated extension machine type TV intercom system, the indoor master station for a single station is replaced with the indoor master station 72 to which the additional indoor master station 73 can be connected, or the indoor master station 7 to which the additional indoor master station 73 can be connected in advance.
There is a drawback that 2 must be installed.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and it is easy to add an indoor master unit and is different from an adapter device for expansion or a single-station indoor master unit. It is intended to provide a TV intercom device that does not require an additional indoor master unit having a configuration.

[0006]

In order to achieve this object, a television door intercom apparatus of the present invention is a door intercom equipped with a camera for capturing an image of a visitor and outputting a video signal, and a television monitor for monitoring the video signal. And a plurality of indoor masters provided with a handset for making a call with the entrance slave, and each of the plurality of indoor masters has an off-hook detection circuit for detecting an off-hook of the handset and an off-hook detection circuit. Equipped with a reset signal sending circuit that sends a reset signal to another indoor master unit according to the operation, and a video signal cutoff circuit that cuts off the video signal output to the television monitor by the reset signal output from the reset signal sending circuit ing.

[0007]

In this television door intercom device, when a handset is off-hooked in one indoor master unit in response to a call from the entrance slave unit by a visitor, the off-hook detection circuit operates and the reset signal transmission circuit causes another indoor master unit to operate. A reset signal is sent to. When the off-hook detection circuit of another indoor master receives this reset signal, the video signal cutoff circuit operates to cut off the video signal output to the television monitor. Therefore, in one indoor master device, the video signal from the entrance slave device can be monitored by the TV monitor of the indoor master device, and in other indoor master devices, the image is erased.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a TV door intercom apparatus according to the present invention will be described below with reference to the drawings. 1 and 2, the TV intercom device according to the present invention is a door subunit SQ.
It is provided with a plurality of indoor master devices AM and BM connected to.

The entrance slave unit SQ includes a speaker 2, a microphone 3, a call button 4, a camera 5 including a camera eye 1 for photographing a visitor, and a video signal FM modulation circuit 6 for modulating a video signal output from the camera. It is provided. The plurality of indoor master devices AM and BM have the same configuration, and each of them is provided with a video signal FM demodulation circuit 22 for demodulating a video signal and a television monitor 25 for monitoring the demodulated video signal.

An off-hook detection circuit 33 for detecting the off-hook of the handset is provided in each of the plurality of indoor master units AM and BM.
And a reset signal transmission circuit 35 for transmitting a reset signal to another indoor master unit according to the operation of the off-hook detection circuit,
A video signal cutoff circuit 24 for cutting off the demodulated video signal output to the television monitor by the reset signal output from the reset signal transmission circuit is provided.

[0011] In addition, the terminal T ₂ of the terminal T ₁ and the indoor master unit AM of the entrance door station SQ is connected by a cable L _1, the indoor master unit AM
And BM are connected by a cable L ₂ . Entrance cordless handset SQ
Is a camera 5 provided with a camera eye 1, a video signal FM modulation circuit 6, a multiplexing circuit 10, a microphone 3, a speaker 2, a call button 4, an upstream audio signal AM modulation circuit 7, and a downstream audio signal AM.
A demodulation circuit 8 and a power receiving circuit 9 are provided, and the camera 5 is connected via a video signal FM modulation circuit 6 to the video signal input side of a multiplexing circuit 10 to which the terminal T ₁ is connected. Also,
The microphone 3 is connected to the upstream audio signal side of the multiplexing circuit 10 via the upstream audio signal AM modulation circuit 7 to which the call button 4 is connected, and the downstream audio signal side of the multiplexing circuit 10 is the downstream audio signal AM demodulation circuit 8 It is connected to the speaker 2 via.

The indoor master unit AM has a multiplexing circuit 21, a video signal FM demodulation circuit 22, a video signal output circuit 23 incorporating a sync separation IC 26, a video signal cutoff circuit 24, a television monitor 25, an upstream audio signal AM demodulation circuit. 27, an up voice signal amplifier 28, a down voice signal amplifier 29, a down voice signal AM modulation circuit 30, a chime sound phase detector 34, a chime sound generation circuit 32, a receiver 31a, a transmitter 31b, and an off-hook detection magnet 31c. Provided handset 31,
An off-hook detection circuit 33 provided with a 500 kHz tuning circuit 42, a reset signal transmission circuit 35, a power supply circuit 36 and C
The video signal side of the multiplexing circuit 21 is composed of the PU 40, and the video signal output circuit 23 is provided via the video signal FM demodulation circuit 22.
It is pins P ₁ and the connection pin P ₂ video signal cutoff circuit 24
It is connected to the TV monitor 25 via. Also,
The pin P ₄ to which the synchronizing signal f ₃ is output is connected to the pin P ₉ of the reset signal sending circuit 35, and the pin P ₃ to which the lock signal f ₂ is output is connected to the control input side of the CPU 40.

The upstream audio signal side of the multiplexing circuit 21 is connected to the handset 31a of the handset 31 via the upstream audio signal AM demodulation circuit 27 and the upstream audio signal amplifier 28,
The transmitter 31b of the handset 31 is provided with the multiplexing circuit 2 via the downstream audio signal amplifier 29 and the downstream audio signal AM modulation circuit 30.
1 is connected to the downstream audio signal side. Also, the downlink audio signal side of the multiplexing circuit 21 is provided with a chime sound phase detector 34.
Is connected to the control input side of the CPU 40, and the control output side is connected to the handset 31a of the handset 31 via the chime sound generation circuit 32. Further, the reset signal input side of the multiplexing circuit 21 has a pin P of the off-hook detection circuit 33.
₅ and the pin P ₆ is connected to the control input side of the CPU 40. Further, the control output side of the CPU 40 is connected to the pin P ₈ of the reset signal sending circuit 35, and the pin P ₇ is connected to the reset signal sending side of the multiplexing circuit 21.

The control output side of the CPU 40 is connected to the video signal cutoff circuit 24 and the control input side of the power supply circuit 36, and the power supply side of the power supply circuit 36 is connected to the multiplexing circuit 21. The off-hook detection circuit 33, as shown in FIG.
The 500 kHz band pass filter 41, which is composed of the 500 kHz band pass filter 41, the 500 kHz resonance circuit 42, the amplification circuit 43, the detection circuit 44, and the waveform shaping circuit 45, and the pin P ₅ to which the reset signal f ₁ is input is connected to the input side. The output side of is the resistance R of the 500 kHz resonant circuit 42.
It is connected to the reference potential point via ₁₂ and the capacitor C ₃ . The other end of the resistor R ₁₁ to which a signal of 500 kHz is connected is connected to the reference potential point via the tuning coil CL ₁ , and the connection point between the resistor R ₁₁ and the tuning coil CL ₁ is the resistor R ₁₂
And the connection point of the capacitor C ₃ and. Furthermore, 5
The output side of the 00 kHz band pass filter 41 has a resistor R ₁₃
And is connected to the base of the transistor Q ₃ of the amplifier circuit 43 via the capacitor C _4, the emitter is connected to one end of a resistor R ₁₆ and capacitor C ₅ connected in parallel. The other ends of the resistor R ₁₆ and the capacitor C ₅ connected in parallel are connected to the reference potential point. Furthermore, the collector is a resistor R ₁₅
Is connected to the power source + Vcc via a resistor R ₁₄ is connected between the collector and the base. Next, the collector of the transistor Q ₃ is connected to the cathode of the diode D ₂ via the capacitor C ₆ of the detection circuit 44, and the anode is connected to the reference potential point. The cathode of the diode D ₂ is connected to the anode of the diode D ₁ , and the cathode is connected to one ends of a resistor R ₁₇ and a capacitor C ₇ connected in parallel. The other ends of the resistor R ₁₇ and the capacitor C ₇ connected in parallel are connected to the reference potential point.

Further, the transistor Q of the waveform shaping circuit 45
The base of ₄ is connected to the other end of the resistor R ₁₈ to which the cathode of the diode D ₁ is connected, and the emitter is connected to the reference potential point. Further, the collector is connected to the power source + V via the resistor R _19.
cc, and the connection point between the collector and the resistor R ₁₉ is pin P
Connected with ₆ . The off-hook detection magnet 31c provided in the handset 31 is connected to the 500 kHz resonance circuit 42.
Off-hook detection circuit 3 when it is separated from the tuning coil CL _{1 of}
3 operates, and a control signal is sent to the CPU 40. When the reset signal f ₁ is input from the pin P ₅ , the off-hook detection circuit 33 operates similarly and the control signal is sent to the CPU 40. As shown in FIG. 4, the reset signal sending circuit 35 is composed of a switch circuit 46 and a buffer circuit 47, the other end of the capacitor C ₂ to which the pin P ₉ is connected is connected to the base of the transistor Q 2, and the emitter is the resistor R _6. Is connected to the reference potential point via. The collector is the power supply + V
A resistor R ₅ is connected between the collector and the base.

Further, the emitter of the transistor Q ₁ which is provided to the switching circuit 46, the resistor R ₄ is connected, the other end of the resistor R ₄ is connected to the connection point of the emitter of the resistor R ₆ and the transistor Q ₂ There is. Further, the base of the transistor Q ₁ is connected to the pin P ₈ via the resistor R ₂ , and the collector is connected to the pin P ₇ via the capacitor C ₁ . This collector is connected to the other end of the resistor R ₁ whose one end is connected to the reference potential point, and is connected to the resistor R ₃ between the base and the emitter.

As shown in FIG. 5, the video signal output circuit 23 has a built-in sync separation IC 26. Sync separation I
C26 is composed of an AFC 50, a VCO 51, a countdown circuit 52, a lock detection circuit 53, a sync separation circuit 54, and a vertical sync separation circuit 55, and a pin P ₁₇ of the sync separation IC 26 to which the pin P ₁ of the video signal output circuit 23 is connected. Is connected to the input side of the sync separation circuit 54, and the output side is connected to the input side of the vertical sync separation circuit 55 and the AFC 50.
The output side of the vertical sync separation circuit 55 is connected to the pin P ₁₅ that outputs VD _OUT, and the output side of the countdown circuit 52 is connected to the input sides of the AFC 50 and the lock detection circuit 53. The output side of the lock detection circuit 53 has a pin P ₁₉
It is connected to the pin P ₄ of the video signal output circuit 23 via. Further, the output side of the lock detection circuit 53 is connected to pin P3 of the video signal output circuit 23 via a pin P _18. Next, the output side of the lock detection circuit 53 is connected to the pin P ₁₆ which outputs EXC, and the output side of the countdown circuit 52 is connected to the pin P ₁₄ which outputs HD _OUT .

The VCO 51 is a VCO _IN and a VCO _OUT.
Is connected to pin P ₁₃ and pin P ₁₂
The output side of 50 is connected to the pin P ₁₁ which outputs AFC _CTL . Further, the output side of the AFC 50 is connected to the VCO 51. The pin P ₁ and Pin Pin P ₁ is provided a waveform shaping circuit 23a between P ₂ of the video signal output circuit 23
The waveform of the video signal input from is shaped and sent to the video signal interruption circuit 24 via the pin P ₂ .

In the TV intercom apparatus thus constructed, when the call button 4 of the entrance slave unit SQ is pressed, the phase of the AM modulation of the upstream voice signal AM modulation circuit 7 is reversed and the indoor circuit is passed via the multiplexing circuit 10. A call signal is sent to the master units AM and BM. In the indoor master units AM and BM, since it can be known that there is a calling signal by the multiplexing circuit 21 and the chime sound phase detector 34, the chime sound generation circuit 3 is controlled by the CPU 40.
2 operates to send a chime sound to the handset 31a of the handset 31.

In the indoor master units AM and BM, since the power supply circuit 36 operates under the control of the CPU 40, the image is displayed on the television monitor 25. Then, for example, when the indoor master unit AM goes off-hook, the off-hook detection circuit 33 of 500 k shown in FIG.
From the tuning coil CL ₁ of the Hz resonance circuit 42 to the handset 31
Is released, so that it is notified from the pin P ₆ to the CPU 40 that it has been off-hooked. Further, since the power supply circuit 36 operates under the control of the CPU 40, an image is output from the television monitor 25. When the image is output from the television monitor 25, the lock detection circuit 53 provided in the sync separation IC 26 shown in FIG. 5 of the video signal output circuit 23 operates and the lock signal f ₂ is sent to the CPU 40 via the pin P ₃ . Next, since the synchronizing signal f ₃ is input to the reset signal sending circuit 35, the switch circuit 46 shown in FIG.
The reset signal f ₁ is sent to. When the off-hook detection circuit 33 of the indoor master device BM receives the reset signal f ₁ , the off-hook detection circuit 33 operates. Off-hook detection circuit 3
3 operates, the video signal cutoff circuit 2 is controlled by the CPU 40.
4 operates, the path to the television monitor 25 is cut off, and at the same time, the downstream audio signal amplifier 29 becomes inoperative.

In the above embodiment, the video signal and the audio signal are FM-modulated and AM-modulated and transmitted, respectively. Regarding this transmission method, one of the video signal and the audio signal is the baseband and the other is the FM or the FM signal. It may be performed by an AM modulation / demodulation method.

[0022]

As is apparent from the above description, according to the television door intercom apparatus of the present invention, it is possible to easily install an indoor master unit, and it is different from the adapter device or the single station indoor master unit for expansion. It is no longer necessary to provide an indoor master unit for additional configuration.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a TV door phone device according to the present invention.

FIG. 2 is a block diagram showing an embodiment of a TV intercom device according to the present invention.

FIG. 3 is a block diagram showing an embodiment of an off-hook detection circuit provided in the TV door intercom apparatus according to the present invention.

FIG. 4 is a block diagram showing an embodiment of a reset signal transmission circuit provided in the TV door phone apparatus according to the present invention.

FIG. 5 is a block diagram showing an embodiment of a sync separation IC provided in a TV door phone apparatus according to the present invention.

FIG. 6 is a block diagram of a conventional TV intercom device.

FIG. 7 is a block diagram of a conventional TV intercom device.

[Explanation of symbols]

 24 ··· Video signal cutoff circuit 25 ··· TV monitor 31 · · · Handset 33 · · Off-hook detection circuit 35 ··· Reset signal sending circuit SQ ・ ・ ・ ・ Entry unit AM, BM ・ ・ ・ ・ ・ Indoor base unit

Claims (1)

[Claims] 1. A plurality of front doors provided with a camera for picking up an image of a visitor and outputting a video signal, a television monitor for monitoring the video signals, and a handset for communicating between the front door and the handset. Of the indoor master unit, and each of the plurality of indoor master units sends an off-hook detection circuit for detecting an off-hook of the handset and a reset signal to another indoor master unit according to the operation of the off-hook detection circuit. And a video signal cutoff circuit for cutting off the video signal output to the television monitor by the reset signal output from the reset signal transmission circuit.