JPH0124467B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a meeting line termination method used for maintenance of a communication system.

Conventionally, a meeting line between multiple stations is terminated by an ON HOOK signal from the calling station indicating the termination of the call.

Such conventional methods include, for example, EQIPMENT, published by NEC Corporation in August 1982.
MANUAL FOR NMS―402B TELEPHONE
EQIPMENT (equipment manual)
The system described in 402B Telephone Equipment (Reference 1) is known.

However, in the conventional method, it is turned on at the calling station.
As long as the HOOK signal is not sent, the communication line with the called station will continue to be maintained. Therefore, even if the call ends, if the caller forgets to hang up the handset of the calling station, the meeting line becomes occupied, making it impossible for other stations to talk.

SUMMARY OF THE INVENTION An object of the present invention is to provide a meeting line termination method that eliminates the above-mentioned drawbacks.

The method of the present invention is a method for terminating a meeting line used for maintenance of a communication system consisting of a plurality of stations, in which a first signal indicating the end of the call is sent to the called station at the end of the call. means for receiving a second signal sent from the called station at the end of a call; and a signal when the first signal is not sent within a predetermined time in response to the second signal; The calling station includes control means for controlling the sending means to send out the calling station.

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a block diagram showing a conventional meeting line described in the above-mentioned document 1. In the figure, each station 1
3 are respectively connected to a dedicated transmission line and a dedicated reception line via a connection unit 100. Each of these stations 1 to 3 includes a multifrequency signal oscillator 11 that generates a multifrequency signal using a key switch 14, a receiving circuit 12 that receives the multifrequency signal, and a multifrequency signal that transmits an on-hook or off-hook signal by lifting or hanging the handset. It has a switch 13 which operates to send out the signal from the transmitter. In such a meeting line system, station 2, which is called by station 1, communicates with station 1 in response. However, in such a conventional configuration,
Station 3 cannot make a call while stations 1 and 2 are talking. Therefore, even if the call between station 1 and station 2 ends, unless station 1 hangs up the handset,
ON HOOK signal indicating end of call is not sent,
The line may be put on hold between stations 1 and 2 because the calling station (in this case, station 1) forgets to hang up the handset.

Such a situation occurs when a head-on type handset is used and an off-hook signal is not sent through the switch even if the handset is removed at the end of a call.

FIG. 2 is a block diagram showing one embodiment of the present invention.

In the figure, each station 10 to 30 is connected to a transmission line and a reception line via a connection unit 100. Each station 10-30 has a timer 121 added to the conventional receiving circuit of stations 1-3. As will be described later, this timer 121 is provided to automatically terminate a line connection state caused by the calling station not hanging up the handset even though the call has ended. That is, the station 20 called by the station 10 communicates with the station 10 in response.
At the end of the call, it is also turned on from station 20 (called party).
The HOOK signal is transmitted to operate the timer in the receiving circuit 120 of the station 10 (calling side). I forgot to hang up the handset at station 10, so I called ON HOOK from station 10.
If no signal is sent, this timer controls the multi-frequency oscillator to automatically send an ON HOOK signal after a predetermined period of time, while at the same time
In this case, an alarm sound is generated to prevent the calling party from forgetting to hang up the handset.

As described above, the present invention has the advantage that the meeting line is not held on hold between specific offices, and the meeting line can be used effectively.

[Brief explanation of drawings]

FIG. 1 is a block diagram illustrating a conventional meeting line termination method, and FIG. 2 is a block diagram illustrating an embodiment of the present invention. In the figure, 1 to 3, 10 to 30... stations, 14
...Author switch, 11...Multi-frequency signal oscillator,
12, 120...reception circuit, 121...timer.

Claims (1)

[Claims] 1. A plurality of stations are connected to each other via dedicated transmitting and receiving circuits, and each station of the plurality of stations has a transmitting circuit that generates a multi-frequency signal, a receiving circuit that receives the multi-frequency signal, a telephone receiver and a receiver. In a call termination method for a meeting line used for maintenance of a communication system, the line has a switch that operates to transmit on-hook signals and off-hook signals from a multi-frequency oscillator when left on the line, a call between any two of the plurality of stations. sending means for sending a first on-hook signal indicating the end of a call to the called station at the end of the call; and receiving means for receiving a second on-hook signal sent from the called station at the end of the call; Each station includes control means for controlling the sending means to send the first on-hook signal when the first on-hook signal is not sent within a predetermined time in response to the second on-hook signal. A meeting line termination method characterized by: