JPS5832817B2 - Kakuseiyobidashiniyoruuchiawasetsuushinhoushiki - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a meeting communication system that performs calling and communication settings using amplified sound.

The call meeting call system using amplified sound is widely used as a maintenance call system for microwave, coaxial, etc. communication lines, or as a communication connection system within a station building.

When making a call using this method, in the conventional method, the call on the call line is always amplified unnecessarily by the paging speaker, which creates annoying noise and noise for people who are talking on other lines or people who are not involved in the call. Become.

The present invention is an improvement on this, and aims to provide a system in which the calling speaker operates only during a loudspeaker call.

The present invention is characterized in that each station is provided with a ringing trigger signal oscillator, and when performing a loudspeaker call, a ringing trigger signal is sent out, and only the subsequent ringing sound is amplified to operate a speaker circuit, thereby performing a loudspeaker call. It is something.

Therefore, calls without a ring trigger signal will be sent from the speaker.
Since the sound is not amplified, annoyance can be prevented.

In the present invention, a plurality of stations are connected to a common communication path, and each of the plurality of stations includes a transmitter for transmitting an audio signal current to the communication path, and a transmitter for transmitting the audio signal current on the communication path to a low-volume voice. In a communication method that includes a receiver that converts the audio signal current of the communication channel into a loud voice and a speaker that converts and amplifies the voice signal current of the communication path into a loud voice, the plurality of stations each includes a call trigger signal oscillator that sends out a signal current of a predetermined frequency, and a switch that directs the output of this oscillator to the communication path;
a selection circuit that selectively receives the signal current of the predetermined frequency sent to the communication path; and the communication path that starts within a certain period of time after the selection circuit receives the signal current of the predetermined frequency. and means for applying an audio signal current to the speaker until the audio signal current is interrupted.

This will be explained below by way of example with reference to the drawings.

FIG. 1 is a circuit diagram of a device according to an embodiment of the present invention.

In FIG. 1, stations 2A to 2N are connected to a plurality of common communication paths 1. In FIG.

At each station 2A to 2N, the selection switch 3 selects the communication path 1.
The structure is such that two or more stations can be connected to the transmitter 4 selectively.
They can talk to each other using the telephone receiver 5.

At this time, the signal on the communication path 1 is guided to a mixing circuit 6 at each station, and the output thereof is amplified by an amplifier 8 via a switch 7 and amplified by a speaker 9.

This is used to call the other station, and the other station listens to the voice coming from the speaker 9, goes to the location of the transmitter 4 and handset 5, and responds. Communication path 1 is selected and communication is set up. Ru.

Here, the feature of the device of the present invention is that it is configured so that the voice of the call is not amplified by the speaker 9 when the call is not made.

To explain this, 10 is a call trigger signal oscillator, the output of which is coupled to the selection switch 3 via a switch 11.

The switch 11 interlocks with the switch 7 by reversing opening and closing.

Further, the signal led from switch 7 to amplifier 8 is branched and coupled to selection circuit 12 and selection circuit 130 inputs.

The selection circuit 12 includes a band p-wave generator that passes only the output frequency of the call trigger oscillator 10, and after rectifying this output, the output is NANDed via a delay operation delay recovery circuit.
It is coupled to circuit 140 input.

- The power selection circuit 13 is equipped with a low-frequency wave generator that passes audio band signals, and after rectifying the output, the output is connected to one input of the NAND circuit 14 and the NAND circuit 14 through a delay recovery circuit.
It is coupled to the input of AND circuit 15.

NAND circuits 15 and 16 constitute a bistable circuit,
Its output is amplified by amplifier 17 and relay winding 18
It is configured to drive.

The contacts of relay winding 18 are shown at r inserted into the speaker 90 circuit.

The operation of the device configured in this way will be explained.

For example, when a 2N station makes a meeting call by loudspeaker call to a 2A station, the 2N station first selects the communication path to be used, closes the switch 11 for a short time, and oscillates and sends out the paging trigger signal f1.

This signal passes through the mixing circuit 6 of each station including the 2A station and is applied to circuits 12 and 13.

Therefore, the calling trigger signal f1 passes only through the circuit 12, and N
A logic value rHJ is given to the AND circuit 14.

The "H" state of Ll is maintained by the delay recovery circuit of circuit 12 for a time tSRf after the paging trigger signal f1 is cut off.

This situation is shown in the operation time chart of FIG.

When Ll is in the state of rHl, when a voice is transmitted from the transmitter 4 of the 2A station, it is applied to the circuits 12 and 13 through the same path as the paging trigger signal f.

Therefore, the audio passes through the circuit 13 and the NAND gate circuit 1
Logic value rHJ is given to L2 of 4 and 15.

As a result, L3 becomes the logical value "L" and L4 becomes rHJ, driving the relay 18, closing the contact r of the speaker circuit, and making it possible to amplify the sound.

Once this audio is interrupted, L2 becomes the logical value rLJ, and the bistable circuit constituted by circuits 16 and 15 is inverted.
Since L4 becomes rLJ, the contact r of the speaker circuit is disconnected.

However, due to the delay recovery circuit of circuit 13, the delay time tsR
Since V is provided, even if the audio is cut off in the middle, the time t S
If the sound is transmitted again into the RV, contact r of the speaker circuit
never breaks.

If a call is made after the time t S RV has elapsed since the sound was interrupted, the call sound will not be amplified by the speaker.

If the circuits 12 and 13 are provided with delay recovery characteristics, the bistable circuit will be reversed immediately when the next voice is not emitted immediately after the call trigger signal f1 or voice is interrupted. can be prevented.

Further, by providing delay operation to the circuit 12, it is possible to prevent malfunction due to short-term noise, etc., and also to prevent the ringing signal tone from being directly transmitted from the speaker.

It is preferable that the delay times tsRvt, tsRf and tSO are each set to about 5 seconds to 20 seconds.

Incidentally, it is preferable to set the positional relationship of the frequencies so that the frequency of the paging trigger signal f1 falls within the blocking range of the low-frequency p-wave generator of the circuit 13.

Furthermore, even if there is a call from another station during a call, an interrupt call can be made using the same process as above.

As described above, the present invention provides a device that can prevent unnecessary amplified sound from being played from a speaker during a call.

Note that the number of communication channels of 10 and the number of each station of 20 described in the above description are not limited.

Further, the present invention can be implemented in the same manner with other configurations of the selection circuits 12 and 130, the configuration of the logic circuit or the bistable circuit, etc. other than those illustrated.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a device of a telephone communication system showing one example of implementation of the present invention. FIG. 2 is a time chart for explaining the operation. 1...Communication path, 2...Station, 3...
...Selection switch, 4...Telephone, 5...
...Telephone receiver, 6...Mixed circuit, 7...
Switch, 8...Intensifier, 9...Speaker, 10...--Call trigger signal oscillator, 11.
...Switch, 12, 13... Selection circuit, 14, 15, 16... NAND circuit, 17.
...Amplifier, 18...Relay winding.

Claims (1)

[Claims] 1. A plurality of stations are connected to a common communication path, and each of the plurality of stations includes a transmitter that transmits an audio signal current to the communication path, and a transmitter that transmits the audio signal current of the communication path. In a communication method that includes a receiver that converts the audio signal to a low-volume voice, and a speaker that converts and amplifies the audio signal current of the communication path to a high-volume voice, and that calls and communication settings are performed using the amplified sound transmitted from the speaker, Each of the plurality of stations includes a call trigger signal oscillator that sends a signal current of a predetermined frequency, a switch that guides the output of this oscillator to the communication path, and a signal current of the predetermined frequency that is sent to the communication path. a selection circuit that selectively receives the audio signal current of the communication channel that is started within a certain period of time after the signal current of the predetermined frequency is received by the selection circuit; A meeting communication system using loudspeaker calling, characterized in that the method comprises: means for giving information to the speaker until the time period of