JPH04172049A - Line monitoring device - Google Patents

Abstract

PURPOSE:To early discover the line faults of the lines of emergency telephone sets scattered on an expressway or the like, and to obtain the cause of the line faults by automatically testing the lines, detecting each kind of faults, and sending an alarm signal. CONSTITUTION:This device is equipped with a clock part 4 which outputs a time signal at the interval of the preliminarily decided time. And also, this device is equipped with a detecting part 1 which outputs the alarm signal after detecting the line interruption, ground interference, and battery interference at the telephone set side of a sound line each time the time signal is inputted except for a period when a communication signal is inputted, and sends the alarm signal after detecting an insulation failure at the telephone set side of the sound line when the input of the communication signal is stopped. Thus, the discovery and the restoring processing of the faults such as the line interruption, ground interference, and battery interference of the lines of the emergency telephone sets scattered on the expressway, can early be operated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a track monitoring device, and more particularly to a track monitoring device for monitoring tracks such as emergency telephones on expressways.

[Conventional technology]

Conventionally, this type of equipment did not exist, and maintenance workers regularly tested the lines of emergency telephones scattered along the expressway using a track tester or the like to carry out maintenance work.

[Problem to be solved by the invention]

As mentioned above, in the past, maintenance personnel regularly monitored the lines of emergency telephones scattered on expressways using test equipment, etc., so it was difficult to make normal calls when using emergency telephones. There was a risk of delays in dealing with problems such as line disconnections, earth-air cross-wires, and battery cross-wires. Further, there was a problem that the efficiency of maintenance work was poor and the maintenance work cycle became long.

[Means to solve the problem]

The track monitoring device of the present invention includes a current limiting resistor and a polarity limiting resistor that are connected in series to each other and connected to an audio line terminal of a telephone, and a current limiting resistor and a polarity limiting resistor that are connected to the telephone via an audio line to detect off-hook of the telephone. a calling section that outputs a calling signal only while detecting off-hook; a clock section that outputs a time signal at predetermined time intervals; and a clock section that is inserted into the audio line and receives the calling signal from the talking section. Except during the period when the time signal is input from the clock section, disconnection of the voice line on the telephone side, ground air cross-wire, and battery cross-wire are detected, and an alarm signal is outputted. and a detection section that detects insulation failure on the telephone side of the voice line and sends out an alarm signal when input of a call signal stops.

〔Example〕

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

FIG. 1 is a block diagram of one embodiment of the present invention.

The operating modes of the embodiment shown in FIG. 1 are broadly divided into a detection mode and a communication mode.

First, the operation in detection mode will be explained.

The detection unit 1 detects a signal from the clock unit 4 at regular intervals (for example, every 3 minutes).
Due to the detection activation signal sent from signal line S1 to S2,
Switching relay rl11. rl12 for a certain period of time (about 50m5
degree), and the line disconnection and crosstalk detection unit 11. switching relay r
111. Audio line L5→L7. Current limiting resistor R9 polarity limiting diode D, audio line L8→L7. A current loop is formed in the order of switching relay RL12 and line disconnection/crosstalk detection section 11. If a loop is detected, it is normal; if the loop cannot be detected, the line is disconnected; if ground voltage or voltage is detected at terminal L5 or L6, a crosstalk fault is detected. Then, ALM is connected to signal line S3→S4.
Send a signal.

When the monitoring unit 3 receives the ALM signal from the detection unit 1,
Displays the corresponding fault and sends a fault signal to the outside.

This fault signal is latched until a normal signal is received from the signal line S3→S4.

The above is the operation in the detection mode, and the above operation is repeated until the emergency telephone 6 goes off-hook.

Next, the operation in call mode will be described.

In the communication section 2, the terminal L1 has negative polarity, and the terminal L
2 has a positive polarity, and normally a loop is not formed by the polarity limiting diode D.

When the emergency telephone 6 goes off-hook, the voice line L2→L
4. Switching relay r122. Switching relay r112, audio line L6→L10. Audio line L9+L5. Switching relay r111y Switching relay r121, audio line L3→
A loop is formed in the order of L1, and a call from the emergency telephone 6 is detected.

When the communication unit 2 detects a loop, it sends a calling signal for the emergency telephone 6 to the exchange through the signal line S7→SS, and connects the voice line via the terminals Lll and L12. or,
At the same time, a call signal is sent to the detection unit 1 via the signal line Sθ→S5.

The detection unit 1 stops operating in the detection mode when the call signal is turned on from the signal line S6→S5, and enters the call mode. When a response signal is received from the exchange side on the signal line SR→S8, a mutual communication state is established, and when the end of the call (loop break from voice line L2→L4 to voice line L3→L1) is detected, the signal line S6→
Turn off the call signal of S5.

In the detection unit 1, switching relays r121 and L122 are operated for a certain period of time by turning off the call signal of the signal line S6→S5,
Insulation defect detection section 12. Switching relay r l 22 #Switching relay rl12. Audio line L6→L8. Polarity limiting diode D, current limiting resistor R, audio line L7→L5. Switching relay rl11, switching relay r l 21 *A loop test is performed in the order of the insulation failure detection unit 12, and if a loop resistance value below a specified value (for example, 20Ω) is detected, it is determined that the insulation is defective and an ALM signal is sent to the signal line S3→S4. Send.

When the monitoring unit 3 receives the ALM signal from the detection unit 1, it displays an insulation failure and sends a failure signal to the outside. If the resistance value is greater than the specified value, the mode is switched to the loop tester detection mode, and the operation in the detection mode is repeated until the emergency telephone 6 goes off-hook.

〔Effect of the invention〕

As explained above, the present invention automatically tests railway lines to detect various faults and send out alarm signals.
This has the effect of enabling early detection and ascertaining the cause of track disturbances on the emergency telephone lines etc. that are scattered on expressways, and allowing quick and accurate responses to track disturbances.

[Brief explanation of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

Claims (1)

[Claims] A current limiting resistor and a polarity limiting resistor are connected in series to each other and connected to the voice line terminal of the telephone, and are connected to the telephone via the voice line to detect off-hook by detecting the off-hook of the telephone. a talking part that outputs a call signal only during the period of time; a clock part that outputs a time signal at predetermined time intervals; Each time the time signal is input from the telephone section, line disconnection, ground air crosstalk, and battery crosstalk on the telephone side of the voice line are detected and an alarm signal is output, and when input of the call signal from the telephone section stops. A track monitoring device comprising: a detecting section that detects insulation failure on the telephone side of the audio line and sends an alarm signal.