JPS60213152A - Remote supervisory system - Google Patents

Abstract

PURPOSE:To monitor plural positions connected in a parity line made through an existing telephone line by using a DTMF signal by providing each position to be monitored with a peculiar timepiece and a monitoring information encoder. CONSTITUTION:A monitoring device 1 consists of a display device 4, monitoring information decoder 5 and a DTMF decoder 6; and each of monitored devices 2, 3 consists of a DTMF encoder 7, timepiece 8 and a monitoring information encoder 9. The timepieces 8 are set up to time t1 and t2 peculiar to respective monitored devices 2, 3. Alarm information is encoded by the monitoring information encoder 9, converted into a DTMF signal fixed by the DTMF encoder 7 and transmitted to the monitoring device 1. Since the DTMF encoder 7 is controlled by the timepiece 8 so as to transmit monitoring information during a specific period, plural monitored positions can be connected through party line connection.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a remote monitoring system, which allows monitoring of multiple points connected to a party line by equipping each monitored point with a unique clock built into an existing telephone. The present invention relates to a remote monitoring system that can be easily implemented through a telephone signal transmission channel using a dual tone multi-frequency (DTMF) signal.

(Prior art and its problems) Conventionally, in remote monitoring of IIj points connected by a party line, a special monitoring signal was assigned to the monitored point and monitoring information was transmitted, so a special signal transmission device was required. Not only that, but also a special transmission path must be provided for transmitting those monitoring signals.

On the other hand, in the method of transmitting surveillance information using DTMF signals, it is necessary to provide an independent telephone signal line from each monitored point, and there is a drawback that each monitored point cannot be connected using the party line connection method. .

(Object of the Invention) The present invention provides a system for transmitting monitoring information of a plurality of monitored points connected by a party line by providing a special signal transmission device and a signal transmission path by equipping each monitored point with a unique clock. Instead, it provides a remote monitoring system that can be easily transmitted using DTMF signals built into existing telephones.

(Structure of the invention) The present invention aims to solve the drawbacks of the above-mentioned prior art.

Each monitored point is equipped with a unique clock, and the clock is used to start the transmission of monitoring information. Monitoring information is transmitted sequentially using DTMF (No. 1) from multiple monitored points connected by a party line. It is.

(Example of the invention) Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a simplified block diagram of a monitoring device and a monitored device according to an embodiment of the present invention, and FIG. 2 shows an operational procedure.

In FIG. 1, 1 is a monitoring device, and a display 4. Monitoring information decoder5. It consists of a DTMF decoder 6, 2 and 3 are monitored devices, each consisting of a DTMT encoder 71 and a monitoring information encoder 9. or,
In FIG. 2, 15 indicates that alarm information is input to the monitored device 2, 16 indicates that alarm information is not input to the monitored device 2, and 17 indicates that alarm information is input to the monitored device 3. 18 indicates that alarm information has not been input to the monitored device 3;
0 indicates the state of the signal transmission path, 11 indicates the monitoring signal of the monitored device 2, and 12 indicates the monitoring signal of the monitored device 3. 13
Since there is no alarm input to the monitored device 2, and 14 indicates that there is no alarm signal to the monitored device 3, the monitoring signal is not transmitted and the transmission path is empty.

The clock 8 is set to a time specific to each monitored device, and is set to 11 for the monitored device 2 + J”j t * for the monitored device 3.The alarm information is set to a time specific to each monitored device. 9, is converted into a DTMF signal determined by the D'1゛MF encoder, and transmitted to the monitoring device IK.At this time, the DTMP encoder is monitored by the clock 8 at a specific time shown in FIG. Since it is controlled to transmit information, multiple monitored devices do not transmit monitoring signals at the same time, and thus multiple monitored points can be connected by a party line connection.

Furthermore, as shown in Figure 2, when no alarm information is input to the monitored device, that is, when the monitored point is normal, no monitoring signal is transmitted even if it is on time, so there is no idle time on the telephone signal channel. Therefore, a remote monitoring system can be easily realized using existing meeting telephone lines without providing a dedicated transmission line for actual monitoring.

(Effects of the Invention) As explained above, the present invention provides a monitoring ID for a plurality of points connected to a party line using an existing telephone line by providing a unique clock and a monitoring information encoder for each monitored point.
Since it can be easily realized using 'rMF signals and the same line can be used for telephone calls, it has an economical effect.

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram showing an embodiment of the present invention using a simplified monitoring device and a monitored device. 1...Monitoring device, 2 and 3...Monitored device, 4...Display device, 5...Monitoring information decoder, 6... ...DTMF decoder, 7...
...D'rMF encoder, 8...Clock, 9...
...Monitoring information encoder. I t'""""' Agent Patent Attorney Uchihara 1f-n

Claims (1)

[Claims] In a remote monitoring system that uses a dual-tone multi-frequency signal, which is a telephone ring signal, as a transmission signal, each monitored point is equipped with a unique clock, and multiple points connected to the same telephone signal transmission path are monitored. This is a remote monitoring method that is characterized by: