JPH09238426A - Child/parent appliance, electric apparatus system and tv door phone system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To share a power source of a child appliance with a parent appliance for size reduction in the child appliance by receiving a power source supplied from the parent appliance through a transmission path with speech signal and picture signal separated, and outputting the speech signal as a voice. SOLUTION: In a door phone system, a feeding part 12 is provided on parent appliance 10 side so as to supply power source to a child appliance side and output terminal is connected with the transformer T side of a choke coil L1 which separates a picture signal and a speech signal. The speech signal transmitted from a child appliance passes through the choke coil L1 and transmitted to a voice input part and voice output part 13. A choke coil L2 is provided on the child appliance 20 side so that the picture signal from a camera 22 can not invade a voice system, a power source system and others. Therefore, the picture signal from the camera 22 is transmitted to a transmission path 16 through a picture signal processing part 24, without being transmitted to a hybrid 25 and a power receiving part 21 side. It is thus possible to eliminate the power source for a child appliance for size and weight reduction in the child appliance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a TV door horn installed in a house.

[0002]

2. Description of the Related Art Visitors press chimes at the entrance to contact their homes, but recently, in addition to these chimes, an interphone or a home visitor to talk with those at home comes in. Some have a camera to check the person. Such a thing is called a TV door horn.

As is well known for interphones, etc., when a switch is pressed by a visitor or the like, a ringer or the like of a device provided inside responds to the switch, so that a person inside the house knows the arrival of the visitor. It is like this. At this point, the camera is activated and the visitors can be confirmed. After the confirmation, if necessary, the person in the house can take off the hook and have a conversation with the visitor. The thing installed at the entrance is called the child machine, and the thing installed in the house is called the parent machine.

The slave unit is connected to the master unit via a transmission line, and signals are exchanged via this transmission line. The video signal is one-way communication from the child device to the parent device, and the audio signal is two-way communication. However, the control signal for obtaining the video signal is configured to be transmitted from the master unit to the slave unit.

In such a TV door horn, as described above, the video signal from the camera, which is the image pickup unit, the audio signal from the microphone or the audio signal to the microphone must be transmitted through one transmission path. In general, multiplexing is performed.

Japanese Unexamined Patent Publication No. 62-257287 discloses a method of FM-modulating a video signal in a band different from that of an audio signal to multiplex the audio signal for transmission (conventional example 1). Also, in the method disclosed in Japanese Examined Patent Publication No. 6-83452, a multiplexing method for transmitting an audio signal and a video signal to each occupant living in the building by a TV door horn attached to a common entrance or the like. Is described (conventional example 2). In any of the conventional examples, a video signal is multiplexed with an audio signal, and the transmission line is effectively used to simplify the wiring and the like.

However, it has not been possible to multiplex a power supply (DC signal) with an audio signal and a video signal for transmission, and the power supply has been separately provided for the master unit and the slave unit. Therefore, in the TV door horn, a camera, an interphone, and the like must be provided on the slave unit side, which causes a problem that the slave unit inevitably becomes large.

[0008]

As described above, there has been a problem in the related art that if a power source is separately provided for the master unit and the slave unit, the slave unit side becomes larger than necessary.

In view of the above problems, it is an object of the present invention to reduce the size of a slave unit by supplying power from the master unit to the slave unit and sharing the power supply on the slave unit side with the power source of the master unit. And

[0010]

According to a first aspect of the present invention, there is shown a concrete configuration on the side of a slave unit, which is an image pickup section; a microphone; a video signal from the image pickup section and a signal from the microphone. A multiplexing unit that multiplexes an audio signal; a sending unit that sends the signal from the multiplexing unit to the same transmission line; and a power supply fed from the master unit on the transmission line, separated from the audio signal and the video signal And a speaker for outputting the voice signal sent from the master unit through the transmission path as voice.

[0011] Here, with reference to the electrical impedance of the speaker, a power receiving portion that is higher in alternating current than this impedance is provided in a branched manner in the transmission path, and the power source fed from the parent device is separated from the audio signal and the video signal. The power was received reliably. The specific configuration is the invention according to claims 2 to 4.

Here, the electric impedance of the speaker is 8 ohms, and the high impedance portion is formed based on this. This high impedance is for 8 ohms, and can be easily realized without constructing a complicated circuit.

That is, if the transmission path for transmitting the audio and video signals has a high impedance, an impedance of the order of kilo ohms or mega ohms is required, but since 8 ohms is the standard here, a relatively small impedance is required. High impedance can be configured.

Further, the structure of the TV door horn system is the invention according to claim 5 and comprises the slave unit according to claim 1 and a device body.

Further, the invention according to claim 6 shows a specific configuration on the side of the master unit which is provided with a portion for supplying a direct current power to the slave unit.

A signal separation unit for separating and receiving a video signal and an audio signal transmitted from the slave unit through a transmission path; a video signal demodulated among the signals separated by the signal separation unit, and a video image A video signal processing unit for displaying from the display unit as;
Of the signals separated by the signal separation unit, an audio output unit that outputs an electric signal sent from the slave unit side as a sound; a sound input unit that sends sound to the slave unit side as an electric signal; Impedance conversion provided between the audio output section and the signal separating section and sending the electrical signal from the audio input section to the slave side and sending the electrical signal sent from the slave side to the audio output section. And a power supply unit for generating a plurality of DC power supplies from commercial power supplies and supplying one DC power supply from the created power supplies to the slave unit side through the transmission path.

The invention according to claims 7 to 9 shows a configuration in which the electrical impedance is set to 8 ohms, like the power receiving portion of the slave unit. Further, in claim 5, an impedance conversion unit is provided to connect to a voice input unit and a voice output unit such as a telephone or an additional speaker. For example, if the impedance of the connected side is 100 ohms, use a transformer or the like to change from 8 ohms to 100 ohms.
Just convert it to ohms. In other words, the impedance conversion portion can transmit a good voice signal to the speaker or the telephone, etc., to which the additional voice signal is added, or to the slave unit side.

In addition, since the power source carries the power source together with the video signal and the audio signal on the transmission path for transmission, the impedance of the power source section is regulated so that the video signal or the audio signal does not sneak into the power source section. It is the invention of claim 10. That is, the AC impedance seen from the transmission line is higher than that of the transmission line.

The configuration of an electric equipment system is the invention according to claim 11 and comprises the master unit according to claim 6 and an equipment body.

The invention according to claim 12 is one in which a TV door horn system is configured by using the electric device system according to claim 5 and the electric device system according to claim 11.

[0021]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a door horn system which is an embodiment of the present invention, and shows only main parts. On the base unit 10 side, various DC power supplies are created by the power supply unit 11 from the commercial power supply (AC100V) and are supplied to each circuit. This part is an AC-DC converter, so-called AC.
-DC converter, DC-DC converter, so-called DC-D
It is composed of what is called a C converter or the like.

FIG. 1 shows only a DC power supply (for example, 6V) supplied to the monitor unit 15 and a DC power supply (for example, 15V) for driving a camera or the like provided on the slave unit side. A power supply unit 12 is provided to supply power to the slave unit, and an output terminal of the power supply unit 12 is provided with a choke coil L for separating a video signal and an audio signal.
1 is connected to the transformer T1 side. The choke coil L1 of the parent device 10 is provided to send the video signal sent from the camera of the child device only to the monitor unit 15 via the video signal processing unit 14. That is, the audio signal sent from the child device does not go to the monitor side as it is, but passes through the choke coil L1, and the audio input unit and the audio output unit 1
3 is transmitted to the telephone set or the speaker.

That is, the choke coil L1 is provided to separate the audio signal and the video signal so that the video signal does not leak into the audio system or the power supply system. For example, a video signal has a frequency band (for example, M) different from the baseband (10 KHz or less) of the audio signal.
If the signal is modulated and transmitted in the slave unit in the Hz band), a filter (for example, a high-pass filter) or the like can be provided in the video signal processing unit 14 of the master unit to further ensure the signal separation.
The demodulation unit of the master device 10 is provided in the video signal processing unit 14.

Further, in the present invention, since the power source on the slave unit side is omitted, the power source is supplied to the slave unit side. Therefore,
It is highly conceivable that the audio signal leaks from the transmission line 16 to the power feeding unit 12. In order to avoid this, the Applicant has proposed that the power feeding unit 1 should have a high impedance with respect to the transmission line 16 only for AC signals, that is, audio signals.
2 was devised.

That is, the power supply unit 12 having a high impedance in terms of alternating current is provided so as to be branched to the transmission line 16, so that the power supply unit 12 does not affect the transmission line 16 through which the voice signal passes, and the voice signal is supplied by the power supply unit. That is, the power supply unit 12 is configured so as not to affect 12. Here, the transmission line 16 is
The present applicant also pays attention to the fact that the speaker is configured with an 8 ohm system, which is the electric impedance of the speaker, and the signal can be easily separated by providing a power supply section 12 having a high impedance in terms of alternating current. doing. That is, since it is for 8 ohms, the circuit can be configured relatively easily. With such a configuration, the DC voltage can be multiplexed with the audio signal and the video signal and transmitted. Furthermore, if the power receiving unit 21 for receiving the DC power is provided on the child device side 20, it is not necessary to bother to provide a power supply unit on the child device 20 side.

Next, the side of the slave unit 20 which is supplied with power from the master unit 10 will be described with reference to FIG. Similarly to the parent device side, the child device side 20 is also provided with the choke coil L2 so that the video signal from the camera 22 does not reach the audio system or the power supply system. In consideration of the polarity, a diode bridge 23 or the like is provided so that only the positive DC voltage supplied from the parent device can be separated.

That is, the video signal from the camera 22 is sent to the transmission path 16 via the video signal processing section 24, but is only transmitted to the base unit 10 side and is transmitted to the hybrid 25 and the power receiving section 21 side. Not done. Further, if the video signal processing unit 24 modulates the signal into a frequency band different from that of the audio signal and sends out the signal, the audio signal and the video signal can be multiplexed and the effect of a larger choke coil can be obtained.
That is, since the impedance of the choke coil increases in proportion to the frequency, it is possible to prevent the video signal from flowing into the audio signal system or the power supply system. With the configuration described above, a good video signal can be reliably transmitted from the camera 22, which is the imaging unit, to the base unit 10.

Further, the voice signal from the base unit 10 passes through the hybrid 25, is output from the speaker 26, and the voice input from the microphone 27 on the handset side is the hybrid 2 unit.
5, and is transmitted to the voice processing unit (voice input unit, voice output unit 13) of the parent device 10. Therefore, it is possible to reliably exchange audio signals.

Here, as with the power feeding unit 12, the power receiving unit 21 is configured to have a high AC impedance with respect to the transmission line 16 to ensure more reliable signal separation.
That is, the transmission line 16 is provided with a branching portion, and the power feeding portion 12 is provided there.
Also, the power receiving unit 21 is provided to increase the AC impedance seen from the transmission line 16. The DC voltage received by the power receiving unit 21 is sent to the regulator unit 28, where a plurality of types of DC power supplies are created and supplied to each circuit 29.

FIG. 2 shows a concrete circuit configuration example of the power feeding section 12 and the power receiving section 21. 2 is a diagram in which the power feeding unit 12 and the power receiving unit 21 of FIG. 1 are extracted, and only the power feeding unit 12, the power receiving unit 21, the choke coils L1 and L2, the diode bridge 23, and the transmission line 16 of FIG. 1 are illustrated. .

In FIG. 2, transistors (Q1, Q2) (Q
3, Q4) is used to create the power feeding unit 12 and the power receiving unit 21 so that sufficient current can be supplied to each circuit (not shown), while the transmission line 16 has a high AC impedance. The configuration is as follows.

A brief description of the configuration of this part will be added. The power feeding unit 12 is composed of a two-stage DC amplifier including a PNP transistor Q1 and an NPN transistor Q2.
The emitter of the PN transistor Q2 is connected to the transmission line 16. Further, the emitter of the PNP transistor Q1 is directly connected to the power supply unit 11, and the base of the PNP transistor Q1 is connected to the power supply unit 11 via the resistor R1 and the capacitor C1.

PNP transistor Q which is the output of the first stage
The collector of No. 1 is connected to the base of the NPN transistor Q2 of the second stage, and the emitter serving as the output of the NPN transistor Q2 of the second stage is connected to the transmission line 16. A resistor R4 and a capacitor C2 are connected between the transmission line 16 and the base of the second-stage transistor Q2 so as to supply a stable base voltage. The diodes D1 to D4 are connected so that the current does not flow backward.

Here, an AC impedance of several hundreds of ohms was realized only by providing two transistors. That is, the impedance seen from the branch point A is several hundreds of ohms in an alternating current, and is in an open state.
Although it does not flow into 2, it is possible to form a connected state in terms of direct current. In the figure, resistors and capacitors provided are connected to set a stable DC bias.

The power receiving section 21 has substantially the same structure.
The emitter of the first-stage PNP transistor Q3 is connected to the transmission line, and the emitter of the second-stage NPN transistor Q4, which is an output, is connected to a regulator section (for example, a three-terminal regulator) to obtain a predetermined voltage. Various power supplies can be supplied to the circuit 29.

Since the impedance seen from the transmission line 16 is 8 ohms, the power supply section 12 and the power reception section 21 have a high AC impedance, so that the audio signal or the video signal multiplexed on the DC voltage is directly affected. Instead, it is supplied to each processing unit.

As described above, the power supply unit 12 for 8 ohms
Also, since the power receiving unit 21 has high impedance, leakage of audio signals, video signals, etc. into the power supply system is eliminated. Also, since it is for 8 ohms, it is possible to improve without constructing a very complicated circuit.

In the present invention, only the DC power source is multiplexed and transmitted, but the present invention is not limited to this, and can be extended to a configuration in which a DC signal is used for camera control and the like.

[0039]

As described above, according to the present invention as set forth in the claims, since power can be supplied from the master unit to the slave unit, it is not necessary to purposely provide a power source on the slave unit side, and the slave unit is small and lightweight. Can be realized. Further, if the video signal is modulated in a frequency band different from the base band of the audio signal and transmitted, the audio signal, the video signal and the DC voltage can be easily separated.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a door horn that is an embodiment of the present invention.

FIG. 2 is a specific circuit example of a power feeding unit and a power receiving unit.

[Explanation of symbols]

 10 ... Parent unit 12 ... Power feeding unit 20 ... Slave unit 21 ... Power receiving unit

Claims (12)

[Claims] 1. An imaging unit; a microphone; a multiplexing unit for multiplexing a video signal from the imaging unit and an audio signal from the microphone; and a transmission for transmitting the signal from the multiplexing unit to the same transmission path. And a power receiving unit that receives power by separating the power source supplied from the master unit from the audio signal and the video signal on the transmission line, and outputs the audio signal sent from the master unit on the transmission line as voice. A handset equipped with a speaker and a speaker. 2. The slave unit according to claim 1, wherein the impedance of the transmission line is an electric impedance of the speaker. 3. The slave unit according to claim 1, wherein the electrical impedance is 8 ohms. 4. The power receiving section is provided so as to be branched to the transmission line, and the impedance seen from the transmission line has a higher AC impedance than the electric impedance. Cordless handset. 5. An electric device system comprising: the slave unit according to claim 1; and a device body. 6. A signal separating unit for separating and receiving a video signal and an audio signal transmitted from a slave unit through a transmission path; and demodulating a video signal of the signals separated by the signal separating unit. , A video signal processing unit for displaying as a video from the display unit;
Of the signals separated by the signal separation unit, an audio output unit that outputs an electric signal sent from the slave unit side as a sound; a sound input unit that sends sound to the slave unit side as an electric signal; Impedance conversion provided between the audio output section and the signal separating section and sending the electrical signal from the audio input section to the slave side and sending the electrical signal sent from the slave side to the audio output section. And a power supply unit for generating a plurality of DC power supplies from commercial power supplies and supplying one DC power supply from the created power supplies to the slave unit side through the transmission path. Base unit. 7. The master unit according to claim 6, wherein the impedance of the transmission path is an electric impedance of the speaker. 8. The master unit according to claim 7, wherein the electrical impedance is 8 ohms. 9. The master unit according to claim 6, wherein one impedance of the impedance conversion unit is 8 ohms, and the other impedance converted is 100 ohms. 10. The power supply unit is provided so as to be branched to the transmission line, and the impedance viewed from the transmission line has a higher AC impedance than the electric impedance. Parent machine. 11. A base unit according to claim 6, and a device body;
An electric equipment system comprising: 12. An electric equipment system according to claim 5,
The electric device system according to claim 11, and T
V door horn system.