JPH054295U - Underground alarm system - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent accidents such as cutting and damage of underground buried objects due to excavation work on the ground. [Structure] A detection line 2 laid in parallel on a buried object 3 at a predetermined interval, and a signal current is sent to the detection line 2 to detect an abnormality in the signal current. And a monitoring panel 1 for issuing an alarm.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an alarm device for preventing cutting or damage to underground buried objects such as electricity, gas, and water due to excavation work.

[0002]

[Prior Art]

 Conventionally, when an underground buried object such as electricity, gas or water is constructed, a color or a color indicating the type of the underground buried object is displayed between the buried object and the surface of the ground so as to indicate the existence of the buried object. A display sheet made of synthetic resin with letters was embedded. If this display sheet is dug out during excavation work, etc., it is known that there is a buried object displayed below it, and it is possible to prevent the underground buried object from being cut or damaged. ..

[0003]

[Problems to be solved by the device]

 The conventional means for preventing damage to buried objects are as described above, but when performing construction with large civil engineering machinery or when digging, the display sheet is hidden in the excavated soil. Since it is often overlooked, it has a problem that it may cut or damage underground buried objects.

The present invention has been made to solve the above problems, and when there is a risk of cutting or damaging an underground buried object due to excavation work or the like, a warning should be issued without fail. The purpose is to obtain an underground buried object alarm device that can be activated to prevent accidents.

[0005]

[Means for Solving the Problems]

 The underground buried object alarm device according to the present invention includes a detection line laid side by side at a predetermined interval on the underground buried object, a means for sending a signal current to this detection line, and a signal current for this signal current. When an abnormality occurs, a means for detecting the abnormality and issuing an alarm is provided.

[0006]

[Action]

 According to the underground buried object alarm device of the present invention, when the ground above the underground buried object is excavated and the excavation tool cuts this detection line, an abnormality occurs in the signal current sent to the detection line and an alarm is generated. The device detects an abnormality of the signal current flowing through the detection line and issues an alarm.

[0007]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic vertical sectional view showing an embodiment of the underground buried object alarm device, FIG. 2 is a diagram showing another example of use of the underground buried object alarm device, and FIG. 3 is a system diagram of the embodiment. Is. In the figure, 3 is an underground buried object such as electricity, water and gas, 2 is a detection line buried in parallel between this underground buried object 3 and the ground surface, 4 is a laid detection line 2 and the ground A repeater installed at a key point such as a corner of the middle buried object 3 or a point with an appropriate interval, 5 is a terminal device installed at the end of the detection line 2, and 1 is a monitoring panel. A power supply device that sends a current or a signal current to the detection line 2 in the monitoring panel 1, a device that detects a current or a signal current flowing in the detection line 2, and if the detected current or signal current is different from the normal one, There is a device that gives an alarm according to the difference. The detection wire 2 is an electric wire coated with a suitable insulating coating, and may be buried as it is or may be buried in a suitable protective tube. The repeater 4 contains a resistor having a relatively high resistance value, and the terminator 5 contains a resistor having a relatively low resistance value. Reference numeral 7 is a branching device, which is installed at the branching point of the branching line and has a built-in resistor having a relatively medium resistance value in parallel with the branching line. 6 is a movable detector which can move.

Next, the operation will be described. The parts to be buried in the ground, such as the detection line 2, the repeater 4, the terminating device 5, and the branching device 7, may be buried at the same time when the buried work of the underground buried object 3 is completed and backfilled. The monitoring panel 1 may be installed at an appropriate place for ground monitoring or the like. First, a method of detecting by applying a constant voltage from the monitor panel 1 to the detection line 2 and passing a current through the detection line 2 which is a normal detection method will be described. In FIG. 1, when there is no abnormality, the current flowing from the monitoring panel 1 to the detection line 2 flows through the repeater 4a, the current flowing through the repeater 4b, and the terminating device 5. A constant current that is the sum of the current and the current flows. However, for example, it is assumed that the road surface or the like is excavated at a point between the relays 4a and 4b, and the detection line 2 at that location is cut by a drilling tool. Then, the current flowing from the monitor board 1 to the detection line 2 is only the current flowing through the repeater 4a. Since the repeater 4 is a resistor having a relatively high resistance value, the amount of current flowing only through the repeater 4a is small, and the current detection device in the monitoring panel 1 immediately detects that the current has decreased. The alarm means gives an alarm in response to the detection. In FIG. 1, when the detection line 2 between the monitoring panel 1 and the repeater 4a is disconnected, the current becomes zero, and when the detection line 2 between the repeater 4b and the terminator 5 is disconnected. The total current of the current flowing through the repeater 4a and the current flowing through the repeater 4b flows. Since the amount of current differs depending on the cut position, the monitoring panel 1 can determine the cut position based on the detected current amount, and displays the determined cut position and issues an alarm.

FIG. 2 shows a means for detecting the position of the detection line 2 from the ground, that is, the buried position of the underground buried object 3. A signal current is sent from the monitoring panel 1 to the detection line 2 and the movable detector 6 is moved on the ground, and the electromagnetic effect generated from the signal current flowing in the detection line 2 is measured to measure the detection line 2 The position, that is, the buried position of the underground buried object 3 can be confirmed. As a result, excavation work can be performed without damaging the underground buried object 3.

In the above embodiment, the repeater 4, the terminating device 5 and the branching device 7 are described as having resistors built therein, but impedances utilizing resonance may be used. Moreover, if an alarm device is installed in the repeater 4, the terminating device 5, and the branch device 7, an alarm can be issued near the construction site and the worker can be directly alerted.

[0011]

[Effect of the device]

 As described above, according to the present invention, the signal line is buried at a predetermined interval above the underground buried object, and the current of the signal line is detected to issue an alarm. By knowing the existence of the structure, it is possible to prevent accidents such as cutting or damaging the underground structure during excavation work.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an underground buried object alarm device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a usage example of an underground buried object alarm device according to an embodiment of the present invention.

FIG. 3 is a system diagram of an underground buried object alarm device according to an embodiment of the present invention.

[Explanation of symbols]

 1: Monitoring panel 2: Detection line 3: Underground object 4: Repeater 5: Terminator 6: Movement detector 7: Branch device In the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims for utility model registration] [Claim 1] A detection line laid in parallel on a buried object at a predetermined interval, a means for sending a signal current to the detection line, and a signal current An underground buried object alarm device comprising means for detecting an alarm when an abnormality occurs and issuing an alarm.