JP4534792B2 - Intercom system - Google Patents

Description

  The present invention relates to an improvement of an interphone system configured by connecting an interphone master unit and a door phone slave unit via a signal line.

  This type of intercom system is used in apartment houses and the like and is already known.

FIG. 9 shows a basic configuration of an intercom system shown in Patent Document 1 below.
The doorphone slave unit 100 installed at the entrance of each dwelling unit and the interphone master unit 200 installed in the dwelling unit are connected by a two-wire signal line C, and a call button (not connected) of the doorphone slave unit 100 is connected. If the dwelling unit is called by operating (illustrated), the ringing sound is generated on the base unit 200 side, and if the dweller responds, the customer and the dweller at the front door are connected via both microphones MIC and speaker SP. You can talk for a predetermined time between them.
Here, the doorphone sub unit 100 includes a call circuit unit 110, a demultiplexing circuit unit 111, and a power supply circuit unit 112. The call circuit unit 110 for calling uses a microphone that amplifies an audio signal input through the microphone MIC. The amplifier A1 includes a speaker amplifier A2 that amplifies a voice signal output through the call circuit unit 110 and outputs the amplified signal to the speaker SP.

  Also, one interphone master device 200 outputs an alarm to the door phone slave unit 100 when an abnormality is detected in the call circuit unit 210, the power circuit unit 211, the demultiplexing circuit unit 212, and the master device 200 for calling. An alarm signal transmission circuit unit 213, a fire sensor, a security sensor (not shown) such as a security sensor, and the like, to which an abnormal event occurrence detection unit 214 is connected. The call circuit unit 210 is input through a microphone MIC. A microphone amplifier A1 that amplifies the audio signal and a speaker amplifier A2 that amplifies the audio signal output through the call circuit unit 210 and outputs the amplified audio signal to the speaker SP are provided.

  The two-wire signal line C connecting the doorphone slave unit 100 and the interphone master unit 200 is multiplexed with a voice signal for a call, a system control signal, and a drive power supply to the doorphone slave unit. These signals are multiplexed or separated by the demultiplexing circuit unit 111 of the intercom master unit 100 and the demultiplexing circuit unit 212 of the interphone master unit 2.

In such a system, when the base unit 200 detects an abnormality of the security sensor, an alarm sound signal is superimposed and sent to the doorphone slave unit 100 through the signal line C. As a result, the doorphone slave unit 100 is The alarm sound can be output to the outside.
Japanese Patent No. 3414036

  By the way, in such an intercom system, when an alarm sound is output from a door phone slave unit to notify an abnormality to an outdoor person, it is necessary to increase the volume of the alarm sound in consideration of noise and the like.

  However, if the signal level of the alarm sound sent from the interphone master unit to the door phone slave unit is simply increased, the upper limit of the power supply voltage that is multiplexed on the signal line and supplied from the interphone master unit to the door phone slave unit will be affected. Therefore, the first problem that the alarm sound waveform may be distorted and the input to the speaker amplifier that amplifies the alarm sound signal in the door phone slave unit becomes excessive, and the output of the speaker amplifier Is clipped, and the second problem is that the alarm sound is distorted.

  The present invention has been proposed to solve such problems, and provides an intercom system that can output a loud alarm sound from a doorphone slave unit in a simple manner without causing distortion in the alarm sound. With the goal.

In order to achieve the above object, in claim 1, an interphone master unit having an abnormality monitoring function, a speaker and a speaker amplifier, and a door phone slave unit that operates upon receiving drive power from the interphone master unit, In the intercom system configured to send an alarm sound signal through the signal line from the interphone base unit to the door phone slave unit when the interphone base unit detects an abnormality. The interphone master unit includes an alarm control signal sending means for sending an alarm control signal before and after the alarm sound signal, and the doorphone slave unit stores a gain state of a speaker amplifier, When an alarm control signal sent before is received, the gain of the speaker amplifier is increased while it is sent after the warning sound signal. When receiving the alarm control signal, the interphone master unit having the audio signal gain switching means for returning the gain of the speaker amplifier to the original state has the alarm control signal before and after the alarm sound signal. An alarm control signal sending means for sending, the door phone slave unit stores the gain state of the speaker amplifier, and when receiving the alarm control signal sent before the alarm sound signal, the gain of the speaker amplifier On the other hand, when an alarm control signal sent after the alarm sound signal is received, a sound signal gain switching means for returning the gain of the speaker amplifier to the original state is provided.

And the said alarm control signal is comprised as the same frequency signal.

Furthermore, the door phone sub unit further includes a television camera, and the audio signal gain switching means is configured to stop the power supply of the television camera when detecting the audio signal gain switching signal.

According to the present invention, since the gain of the speaker amplifier built in the door phone slave unit is increased, there is no need to increase the level of the alarm sound and send it to the door phone slave unit. The alarm sound signal is not distorted due to the influence of the upper limit value of the power supply, and the input of the amplifier that drives the speaker is not excessive.

  Therefore, the volume can be increased without distorting the alarm sound.

Further, according to the present invention, since the alarm control signal is transmitted before and after the alarm sound signal, multiplexing is easy, and by referring to the state of the gain change of the speaker amplifier, the alarm control signal can After increasing the gain and outputting the alarm sound, the gain can be restored to the original state by the alarm control signal in the same manner.

And since the alarm control signal added before and behind an alarm sound signal is comprised by the same frequency, it is not necessary to provide the detection circuit of a frequency separately, respectively.
Furthermore, while increasing the gain of the speaker amplifier, so to stop the driving of the television camera to be built, a camera drive power can be turned to the speaker amplifier.
For this reason, the power supply of the speaker amplifier does not occur, and a high volume alarm sound can be output stably.

  Embodiments of the present invention will be described below.

  FIG. 1 is a block diagram showing an example of the basic configuration of the first present invention. Note that the basic operation is the same as that of the system shown in the prior art, and a description thereof will be omitted.

  In this intercom system, the doorphone slave unit 1 and the interphone master unit 2 are connected by a signal line C. The doorphone slave unit 1 includes a call circuit unit 10, a power supply circuit unit 11, a demultiplexing circuit unit 12, an audio. And signal gain switching means 13. Here, the audio signal gain switching means 13 includes a gain switching signal detection circuit unit 13a and a gain switching circuit unit 13b, and the call circuit unit 10 includes a microphone amplifier A1 that amplifies the audio level input through the microphone MIC. And a variable gain speaker amplifier A2 that amplifies the sound level output through the call circuit unit 10 and outputs the amplified sound level to the speaker SP.

  The audio signal gain switching means 13 includes a gain switching signal detection circuit unit 13a and a gain switching circuit unit 13b. The gain switching signal detection circuit unit 13a switches the audio signal gain transmitted from the base unit 2 through the signal line C. A signal is detected.

  The call circuit unit 10 includes a microphone amplifier A1 that amplifies the audio signal input through the microphone MIC, and a speaker amplifier A2 that amplifies the audio signal output through the call circuit unit 10 and outputs the amplified signal to the speaker SP. The gain switching circuit unit 13b can increase the gain of the speaker amplifier A2 when the gain switching signal detection circuit unit 13a detects the audio signal gain switching signal. Therefore, the gain of the speaker amplifier A2 can be varied. ing.

  One intercom master unit 2 has a security sensor S such as a fire sensor, a crime prevention sensor, a gas leak sensor, and an emergency push button connected to the abnormal event occurrence detection unit 25, and includes a call circuit unit 20, a power supply circuit unit 21, and a multiplexing circuit. A separation circuit unit 22, an alarm sound signal transmission circuit unit 23, and an audio signal gain switching signal transmission unit 24 are provided. Further, the call circuit unit 20 includes a microphone amplifier A1 that amplifies the sound level output through the microphone MIC, and a speaker amplifier A2 that amplifies the sound level output through the call circuit unit 20 and outputs the amplified sound level to the speaker SP. In such a configuration, the audio signal gain switching signal transmission means 24 transmits the audio signal gain switching signal in a manner to be described later.

  Steps 100 to 105 in FIG. 2 show the basic operation of the system of the present invention having such a configuration.

  That is, when an abnormality occurs in the dwelling unit (100), the master unit 2 detects this state, and transmits an alarm sound signal and an audio signal gain switching signal (101, 102). The signal format in that case is shown in FIG. 3, and on the signal line C, an alarm sound signal Sb is transmitted following the audio signal gain switching signal Sa. This alarm sound signal Sb may be transmitted not only continuously but also intermittently.

  When receiving the audio signal gain switching signal Sa (103), the door phone sub unit 1 increases the gain of the speaker amplifier A2 (104), and then outputs an alarm sound signal based on the alarm sound signal Sb (105). In this case, the audio signal gain switching signal Sa is preferably transmitted as an audible external frequency signal in order to prevent interference with the other alarm sound signal Sb multiplexed. It is not limited.

  It should be noted that the audible external frequency signal transmitted as the audio signal gain switching signal Sa is not limited to one pulse group, and may be a plurality of signals, or may be a plurality of signals transmitted continuously for a certain period of time. Good.

  FIG. 4 shows a frequency configuration diagram of multiple signals in the two-wire intercom system. The multiplexed signal transmitted from the intercom base unit 2 to the intercom unit 1 through the signal line C is normally transmitted by multiplexing the video signal and the call signal to the door phone driving power source. An audio signal gain switching signal that is not audible is added. Here, the alarm sound signal is assigned a frequency band of 100 to 10 KHz, the video signal is assigned a frequency band of 1 M to 10 MHz, and the audio signal gain switching signal is an audible frequency exceeding 10 MHz, as with other control signals. A bandwidth is allocated, but the present invention is not limited to this.

  That is, the frequency band of the audio signal gain switching signal may be any band as long as it does not overlap with other alarm sound signals and video signals.

  These signals are multiplexed and transmitted to the intercom unit 1. In the intercom unit 1, each signal is separated by the demultiplexing circuit unit 12, and each of the call circuit unit 10 and the audio signal gain switching unit 13 is separated. Then, the frequency is discriminated, and the speech circuit unit 10 inputs the audio signal and outputs it from the speaker SP. The audio signal gain switching means 13 inputs the audio signal gain switching signal and performs the above-described processing.

FIG. 5 is a diagram showing another example of the system of the present invention. In this configuration, the audio signal gain switching means 13 is provided with a power reception voltage determination circuit unit 13d, a power reception circuit unit 13e, and a gain switching circuit unit 13b with respect to the basic configuration of FIG.
On the other hand, the base unit 2 includes a power supply circuit unit 21 and a switching circuit 27 as the audio signal gain switching signal transmission unit 24. The switching circuit 27 supplies power to the door phone child unit 1 by the detection of the abnormal event occurrence detection unit 25. The voltage values V1 and V2 are switched.

  Explaining the basic operation, the base unit 2 normally supplies the drive power of the voltage value V1 to the door phone slave unit 1, but when an abnormality occurs, the switching circuit 27 is switched to drive the power supply value of V2. Switching to the power supply, this is the gain switching signal. When the received voltage determination circuit unit 13d of the door phone sub unit 1 detects and determines this V2 voltage value, the gain of the speaker amplifier A2 is increased and changed. Here, the received voltage determination circuit unit 13d can be configured by a comparator, a microcomputer, or the like.

  When the recovery operation is accepted on the base unit 2 side, the switching circuit 27 is switched to set the power supply value to V1. Then, in the door phone sub unit 1, the received voltage determination circuit unit 13d detects the voltage value V1, and returns the gain of the speaker amplifier A2.

  Next, the second present invention will be described. FIG. 6 is a block diagram showing an example of the basic configuration of the second present invention. In this system, the interphone master unit 2 is provided with an alarm control signal transmission means 24 for transmitting an alarm control signal and an alarm sound signal to the doorphone slave unit 1 before and after when an abnormality is detected. It has a configuration.

  The alarm control signal sending means 24 sends a signal in the signal format shown in FIG. 7 when an abnormality occurs on the base unit 2 side, and sends a warning sound signal S following the alarm control signal Sa. Then, the gain of the speaker amplifier A2 is increased by the alarm control signal Sa sent before the alarm sound signal S, and the gain increased by the alarm control signal Sb sent after the alarm sound signal S is restored. The audio signal gain switching control means 13 refers to the gain state of the speaker amplifier A2 when the alarm control signals Sa and Sb are received. When the gain is increased, the audio signal gain switching control means 13 performs alarm control. The gain of the speaker amplifier A2 is restored by the signal, and when the gain is not increased, the gain of the speaker amplifier A2 is increased by the alarm control signal.

  Note that the alarm control signal for restoring the gain of the speaker amplifier A2 may also be used as a restoration signal to be sent to the door phone slave unit 1 when an operation for stopping and restoring the alarm signal is received on the base unit 2 side. Needless to say.

  Therefore, since the audio signal gain switching means 13 performs the above operation with reference to the gain change state of the speaker amplifier A2 when receiving the alarm control signal, the connection between the alarm control signal and the alarm sound signal is established. Even if it becomes unclear, not only can the gain of the speaker amplifier A2 be switched correctly, but also the gain can be increased and returned by simply preparing one type of alarm control signal.

  In the second aspect of the present invention, if the alarm control signals Sa and Sb are configured with the same frequency, the alarm control signal sending means 24 only needs to generate one type of alarm control signal, so that the circuit configuration is simplified. Can be

  FIG. 8 is a block diagram showing an example in which the first and second aspects of the present invention are applied to a television intercom system. In this system, in order to constitute a television intercom system, a camera 19, a video signal processing unit 30, and a camera drive circuit unit 31 are separately provided with respect to the system of FIG. The camera 19 is driven by a driving power source from the parent device 2 and includes a switching circuit 18 that is opened and closed under the control of the camera driving circuit unit 31. The master unit 2 also includes a video signal processing unit 26 and a display unit 27 including a CRT, a liquid crystal monitor, etc. in order to configure a television interphone.

  According to such a configuration, when the gain switching signal detection circuit unit 13a detects the gain switching signal, the camera driving circuit unit 31 is controlled to turn off the switching circuit 18, and the driving power supply to the camera 19 is cut off. To do. Thereby, a camera drive power supply can be turned to an alarm sound output.

The block diagram which shows an example of the basic composition of the 1st present invention The flowchart which shows an example of the basic operation | movement of 1st this invention The figure shown about the transmission aspect of an audio | voice signal gain switching signal The figure which shows an example of the signal transmission format of a signal line The block diagram which shows the other examples of the basic composition of 1st this invention The block diagram which shows an example of the basic composition of the 2nd present invention The figure which shows the transmission mode of the alarm control signal Block diagram when the present invention is applied to a television intercom system Block diagram showing the configuration of a conventional two-wire intercom system

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Door phone subunit | mobile_unit 2 Interphone main unit 13 Audio | voice signal gain switching means 24 Audio | voice signal gain switching signal sending means C Signal line A2 Speaker amplifier

Claims (3)

An interphone master unit having an abnormality monitoring function, a speaker and a speaker amplifier, and a door phone slave unit that operates by receiving drive power from the interphone master unit are connected via a signal line, and the interphone When the base unit detects an abnormality, the interphone system is configured to send an alarm sound signal from the interphone base unit to the door phone slave unit through the signal line.
The intercom master includes an alarm control signal sending means for sending an alarm control signal before and after the alarm sound signal,
The door phone sub-unit stores the gain state of the speaker amplifier, and when receiving an alarm control signal sent before the alarm sound signal, increases the gain of the speaker amplifier, while after the alarm sound signal. An intercom system comprising audio signal gain switching means for returning the gain of the speaker amplifier to its original state when receiving a transmitted alarm control signal. In claim 1 ,
The intercom system, wherein the alarm control signal is configured as the same frequency signal sent before and after the alarm sound signal. In claim 1 or 2 ,
The intercom system further comprising a television camera, wherein the audio signal gain switching means stops the power supply of the television camera when detecting the audio signal gain switching signal.

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