JPH0694568A - Method and apparatus for detecting leak of water - Google Patents

Abstract

PURPOSE:To detect the presence and position of a leak of water without requiring skill. CONSTITUTION:A cock S11 is preliminarily closed on the day before the leak test of a water pipe L11 is performed and, tomorrow morning, the impedance value Z11CA in the ground between points C1 and A1 is measured in such a state that the cock S11 is closed. Thereafter, the impedance value Z12Ca in the ground between the points C1 and A1 is measured in such a state that the cock S11 is opened. When there is a leak at the point A1 the impedance value in the ground around the leak lowers by the opening of the cock S11 and the impedance value Z12Ca lowers as compared with the impedance value Z11Ca and, therefore, it can be detected that a leak of water is generated at a branch part A11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water leak detecting method for detecting the presence or absence of water leak in a water conduit such as a water pipe or a drainage channel, and a water leak detecting device used for carrying out the method.

[0002]

2. Description of the Related Art The occurrence of water leakage in a water conduit such as a water pipe embedded in the ground can be detected by a change in water pressure or the like, but it is necessary to determine the position of the water leakage for restoration. . Therefore, conventionally, a method has been performed in which an audio sound measuring device is applied from the ground surface to a branch portion where water leakage is likely to occur, and a slight difference in water flow sound is heard to determine a water leakage position. In addition, there is also adopted a method in which a worker holds a tool called a towing rod, walks around the ground corresponding to the predicted leak position, and detects the leak position from the movement of the dowsing rod.

[0003]

However, all of the conventional water leak detection methods using the sound-tone measuring device and the dowsing rod use the sense of the operator and therefore require a skill. Moreover, if the detection result is incorrect, the conventional detection method has a problem that the hit rate is low, although the water supply for a long time and the great construction cost are wasted.

In view of the above problems, the object of the present invention is to
It is to realize a water leakage detection method and a water leakage detection device that can reliably detect the presence or absence of water leakage and its position without requiring skill.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, the means taken in the present invention is such that, when a leak occurs in a water conduit in the ground, the impedance value in the ground around the leak position ( The presence or absence of water leakage at that position is detected based on the fact that the resistance value in the case where the measurement signal is DC is lower than the impedance value in the state without water leakage. For example, using the two electrode bodies embedded at the position where the presence or absence of water leakage should be detected, after measuring the first impedance value between the electrode bodies while the supply of water to the water guiding path is stopped, The second impedance value between the electrode bodies is measured while supplying water to the water guiding path, and water leakage occurs in the water guiding path at any position between one side and the other side of the electrode body. The second impedance value is lower than the first impedance value during the operation. Therefore, it is to detect the presence or absence of water leakage between the electrode bodies. Here, as the electrode body, it is possible to use an electrode rod buried in the ground for detecting water leakage, or a metal pipe or water faucet launched from the insulating water supply pipe in the ground to the ground surface. .

As a water leakage detecting device used for carrying out such a water leakage detecting method, it is provided with input terminals to which electrode bodies are respectively connected, and a thyristor and a first thyristor are provided corresponding to a change in impedance value between the input terminals. The drive current converted from the commercial power supply by the transformer is changed and supplied to the second transformer, and the measurement signal generating unit which emits as an AC signal from the second transformer, the rectifying unit that rectifies the AC signal, and the rectifier The amplification unit that amplifies the level of the signal rectified by the unit based on the amplification degree set externally, the movable coil driven by the signal amplified by the amplification unit, and the position corresponding to the impedance value by the movable coil. It is possible to use a water leak detection device or the like having a detection result display unit provided with a displaceable pointer.

[0007]

[Operation] When a water leak occurs in the underground conduit,
Although the underground impedance decreases, it is impossible to detect it from the absolute value of the underground impedance. On the other hand, in the present invention, from the state where there is no water leakage or the state where water supply to the water conduit is difficult to leak, the state where water leakage has occurred or water is supplied to the water conduit to cause severe water leakage. When the state changes to the above state, it is detected that the impedance value in the ground where the water leakage has occurred decreases, and the presence or absence of water leakage at that position is detected. For example, using the two electrode bodies embedded at the position where the presence or absence of water leakage should be detected, after measuring the first impedance value between the electrode bodies while the supply of water to the water guiding path is stopped, When the second impedance value between the electrode bodies is measured in a state where water is supplied to the water guide path, the first impedance value and the second impedance value hardly change when there is no water leakage point. Since the second impedance value becomes lower than the first impedance value when water leakage occurs in the water guiding path at any position between the electrode bodies, The presence or absence of water leakage at the position can be reliably detected.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A water leak detection method according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

Here, in any of the water leak detection methods according to any of the embodiments, the configuration of the water leak detection device commonly used for the implementation will be described with reference to FIG.

FIG. 1 is a block diagram showing the configuration of the water leakage detection device of this example.

In this figure, a water leak detection device 1 of this example is shown.
Corresponds to a change in the impedance value between the input terminals 11 and 12 to which the electrode bodies are respectively connected, and corresponds to the thyristor 13
And a measurement signal generator 10 that changes the drive current 15 converted from the commercial power supply by the first transformer 14 and supplies the changed drive current 15 to the second transformer 17, and outputs the alternating current signal 16 from the second transformer 17. , The AC signal 16 output from the measurement signal generator 10 is provided on the rear side.
Is full-wave rectified with _four diodes D _{1 to} D ₄ ,
It has a rectifying section 20 that is smoothed by capacitors C ₁ and C ₂ of 200 to 470 nF. Further, on the subsequent stage side of the rectification unit 20, there is provided an amplification unit 30 including an operational amplifier 31 for amplifying the level of the signal rectified by the rectification unit 20 based on the amplification degree set externally via the volume V _1. The amplified signal from 31 is output to the detection result display section 40 via the volume V ₂ .
Here, in the detection result display section 40, a movable coil (not shown) driven by the signal amplified by the amplification section 30.
And a current detector 41 provided with a pointer (not shown) that is displaced by the movable coil to a position corresponding to the impedance value. For this current detector 41, a volume rated as a shunt resistor is 200Ω. V ₃ is connected in parallel. Among these constituent parts, in the amplifying section 30, a volume V ₄ having a rating of 10 kΩ supplies an offset voltage to the operational amplifier 31 and a volume V _{5 having a} rating of 10 kΩ.
With this, fine adjustment of the amplification degree of the operational amplifier 31 is possible, and adjustment of the zero point and shake of the galvanometer 41 is possible.

As described above, since it is impossible to detect the presence or absence of water leakage from the absolute value of the impedance in the ground, it is necessary for the water leakage detection device 1 of this embodiment to carry out the water leakage detection method described later. Only the function is provided and the circuit configuration is simplified. In other words, when there is no water leakage or when the water supply to the water conduit is stopped and it is difficult to leak water, when a water leak occurs or when water is supplied to the water conduit and the water leakage is changed to a severe state. ,
If water leakage occurs at any of the positions, the configuration is suitable for detecting that the underground impedance value at the water leakage occurrence point relatively decreases. In addition, the thyristor 13, the first transformer 14, and the second transformer 17 are used to employ the measurement signal generator 10 that emits the AC signal 16 corresponding to the impedance value in the ground. Even if the absolute value is high, the change can be stably detected with a simple circuit configuration.

Next, a water leak detecting method using the water leak detecting device 1 of the present embodiment will be described below.

[Embodiment 1] FIG. 2 is an explanatory view for explaining a water leakage detection method according to Embodiment 1 of the present invention, and shows a plan view of an arrangement state of water pipes (water guide paths).

In FIG. 2, an insulating water pipe L ₁₁ such as a clay pipe or a vinyl chloride pipe is horizontally arranged in the ground, and a water faucet S ₁₁ is provided on the water source side (upstream side) thereof. Has been. Also, from the branch A ₁₁ at the A ₁ point of the water pipe L ₁₁ ,
A metal pipe (not shown) is branched toward the ground and a metal faucet D ₁₁ is provided on the ground, while a water pipe L ₁₁ is provided.
A metal pipe (not shown) is branched from the branching point B ₁₁ at the point B ₁ toward the ground, and a metal faucet D ₁₂ is grounded on the ground.
Is provided.

[0016] To test the leakage of such water pipe L _11, the C ₁ point lateral position of the water pipe L ₁₁ consists of a metal electrode rod D ₁₃ is embedded from the ground, one end thereof is It projects from the ground. Here, the electrode rod D ₁₃ at the C ₁ point is used as an electrode body for measuring the impedance in the ground, while the faucet D ₁₁ at the A ₁ point and the faucet D ₁₂ at the B ₁ point are also It is used as an electrode body for measuring impedance, and any of the electrode bodies is used by being connected to the input terminals 11 and 12 of the water leak detection device 1 shown in FIG.

In such an arrangement state, in the following description, it is assumed that the branch portion A ₁₁ (A ₁ point) is damaged and water leaks there.

First, before conducting a water leakage test on the water pipe L _11, for example, in the evening of the day before the test, the faucet S ₁₁ is kept in a stopped state. This state corresponds to the state without water leakage.

Next morning, using the electrode rod D ₁₃ , the faucet D ₁₁ and the faucet D ₁₂ with the faucet S ₁₁ stopped, the faucet D ₁₁ (A ₁ point) -faucet D ₁₂ (B ₁ point) impedance value between Z11 _AB faucet D ₁₂ (B ₁ point) - electrode rod D ₁₃ (C ₁ point) impedance value between Z11 _BC electrode bar D ₁₃ (C ₁ point) - faucet D ₁₁ (a ₁ point The impedance value Z11 _CA between the two is measured.

Next, after opening the faucet S ₁₁ , the impedance value between the faucet D ₁₁ (A ₁ point) and the faucet D ₁₂ (B ₁ point) Z _{12 AB} faucet D ₁₂ (B ₁ point) -electrode again bar D ₁₃ (C ₁ point) between the impedance value Z12 _BC electrode bar D ₁₃ (C ₁ point) - to measure respectively the impedance value Z12 _CA between faucet D ₁₁ (a ₁ point).

As a result, since there is no water leakage at the branch B ₁₁ at the point B ₁ , regardless of the state of the faucet S ₁₁ ,
Since the impedance in the surrounding ground does not change, the impedance value Z11 _BC and the impedance value Z1 _2BC show the same value.

[0022] On the other hand, in the A ₁ point of the branch portion A _11, in the state in which stopped the faucet S _11, was in a state in which the leakage has stopped, by opening the faucet S _11, water leakage beginning again, since the ground impedance of the surrounding is reduced, the impedance value Z11 _CA in a state that had stopped faucet S _11, when comparing the impedance value Z12 _CA after opening the faucet S _11, the impedance The value Z12 _CA is
Impedance value is lower than Z11 _CA. Similarly, the impedance value Z12 _AB is equal to the impedance value Z11.
It is lower than _AB . As a result, it is possible to reliably detect the occurrence of water leakage at the branch portion A ₁₁ .

On the other hand, when water leakage is occurring at the branch B ₁₁ (point B ₁ ), the water faucet S ₁₁ is closed and the water leakage is stopped in the same manner as above. Electrode D
₁₃ , using faucet D ₁₁ and faucet D ₁₂ , the impedance value between the faucet D ₁₁ (A ₁ point) -faucet D ₁₂ (B ₁ point) Z 11 _AB faucet D ₁₂ (B ₁ point) -electrode bar D ₁₃ ( C ₁ point) between the impedance value Z11 _BC electrode bar D ₁₃ (C ₁ point) - faucet D ₁₁ (a ₁ point) the impedance value Z11 _CA between after measuring each open the faucet S _11, faucet D ₁₁ (A ₁ point) -faucet D ₁₂ (B ₁ point) impedance value Z12 _AB faucet D ₁₂ (B ₁ point) -electrode bar D ₁₃ (C ₁ point) impedance value Z12 _BC electrode bar D ₁₃ ( C ₁ point) - faucet as determined D ₁₁ (a ₁ point) the impedance value Z12 _CA between each for leakage in the a ₁ point of the bifurcation a ₁₁ does not occur, the impedance value Z11 _CA and the impedance value Z12 _CA And are almost the same value. On the other hand, since water leakage occurs at the branch B ₁₁ at the point B ₁ , impedance value Z _{11 BC} when the faucet S ₁₁ is stopped and impedance value Z 12 after the faucet S ₁₁ is opened. Comparing with _BC , the impedance value Z12 _BC is
It is lower than the impedance value Z11 _BC . Similarly, the impedance value Z12 _AB is equal to the impedance value Z11.
It is lower than _AB . As a result, it is possible to reliably detect the occurrence of water leakage at the branch portion B ₁₁ . Further, in this example, the supply of water to the water pipe L ₁₁ is forcibly changed and the impedance values before and after the change are compared, so that the impedance value can be easily and reliably monitored without constantly monitoring the impedance value. Can detect water leaks.

[Embodiment 2] FIG. 3 is an explanatory diagram for explaining a water leakage detection method according to Embodiment 2 of the present invention, in which an arrangement state of water pipes (water guide paths) is shown in a plan view.

In FIG. 3, an insulating water pipe L ₂₁ such as a soil pipe or a vinyl chloride pipe is horizontally arranged in the ground, and a water faucet S ₂₁ is provided on the water source side (upstream side) thereof. Has been. Also, from the branch A ₂₁ at the A ₂ point of the water pipe L ₂₁ ,
A metal pipe (not shown) is branched toward the ground and a metal faucet D ₂₁ is provided on the ground, while a water pipe L _21.
A metal pipe (not shown) is branched from the branching point B ₂₁ at the point B ₂ toward the ground, and the faucet D ₂₂ made of metal is grounded on the ground.
Is provided.

[0026] In order to perform the leakage test of such water pipe L _21, the C ₂ point lateral position of the water pipe L ₂₁ consists of a metal electrode rod D ₂₃ is embedded from the ground, one end thereof is It projects from the ground. Similarly, D _{2 at the} lateral position of the water pipe L ₂₁
A metal electrode rod D ₂₄ is embedded from the ground at the point,
A metal electrode rod D ₂₅ is embedded from the ground at a point E ₂ on the side of the water pipe L ₂₁ , and an electrode F ₂₅ on the side of the water pipe L ₂₁ is embedded.
_{At the two} points, a metal electrode rod D ₂₆ is embedded from the ground, and one of the electrode rods D ₂₄ , D ₂₅ , D ₂₆ has one end protruding to the ground. Where any of the electrode rods D ₂₃ , D
₂₄ , D ₂₅ and D ₂₆ are also used as electrode bodies for measuring the impedance in the ground, while the faucet D ₂₁ at the point A ₂
The faucet D ₂₂ at points B ₂ and B _{2 is} also used as an electrode body for measuring the impedance in the ground.

In such an arrangement state, in the following description, at the point E ₂ , a water pipe L ₂₁ is cracked,
It is assumed that there is a water leak.

First, before conducting a water leak test on the water pipe L _21, for example, in the evening of the day before the test, the faucet S ₂₁ is kept in a stopped state. This state corresponds to the state without water leakage.

[0029] Then, the next morning, in the state stopping the faucet S _21, faucet D _21, D ₂₂ and the electrode rod _{D 23, D 24, D 25} ,
Using the D _26, faucet D ₂₁ (A ₂ points) - electrode rod D ₂₃ (C ₂ points) impedance value between Z21 _AC electrode bar D ₂₃ (C ₂ points) - electrode rod D ₂₄ (D ₂ points) impedance Z21 _CD electrode rod D ₂₄ between (D ₂ points) - electrode bar D ₂₅ (E ₂ points) impedance value between Z21 _DE electrode bar D ₂₅ (E ₂ points) - electrode rod D ₂₆ (F ₂ points) impedance value between Z21 _EF electrode bar D ₂₆ (F ₂ points) - impedance value Z21 _FB respectively measured between faucet D ₂₂ (B ₂ points).

Next, after opening the faucet S ₁₁ , the impedance value Z 22 _AC electrode bar D ₂₃ (C ₂ point) between the faucet D ₂₁ (A ₂ point) and the electrode bar D ₂₃ (C ₂ point) is again displayed. - electrode rod D ₂₄ (D ₂ points) impedance value between Z22 _CD electrode bar D ₂₄ (D ₂ points) - electrode bar D ₂₅ (E ₂ points) impedance value between Z22 _DE electrode bar D ₂₅ (E ₂ points) - electrode rod D ₂₆ (F ₂ points) impedance value Z22 _EF electrode rod D ₂₆ between (F ₂ points) - to measure respectively the impedance value Z22 _FB between faucet D ₂₂ (B ₂ points).

As a result, at point E ₂ , the water tap S ₁₁
At the stop state, it was in a state in which the leakage has stopped, by opening the faucet S _21, leakage begins again, the ground of the impedance of the surroundings is reduced. Accordingly, the impedance value Z21 _DE and impedance values Z21 _EF in a state that had stopped faucet S _21, when the impedance value Z22 _DE and impedance values Z22 _EF after opening the faucet S ₂₁ compares each faucet S The impedance value in the state in which ₂₁ is opened is lower than the impedance value in the state in which the faucet S ₂₁ is stopped.
In contrast, E is the impedance value at the _two points is not involved segment, state and faucet S ₂₁ had stopped faucet S ₂₁
There is no big change after opening. As a result, E ₂
It is possible to reliably detect the occurrence of water leakage at the point. Further, in this example, the supply of water to the water pipe L ₂₁ is forcibly changed and the impedance values before and after the change are compared, so that the impedance value can be easily and reliably monitored without constantly monitoring the impedance value. Can detect water leaks.

As described above, in any of the above-described embodiments, the leakage of water generated at the branch portion of the water conduit such as a water pipe or the pipe itself is measured by the impedance change in the ground before and after changing the leakage state. Therefore, it is possible to reliably detect the presence or absence of water leakage and the position thereof regardless of the skill and sense of the operator.

In each of the above embodiments, the water leak test for a water pipe is described as an example. However, the present invention is not limited to this, and any route can be used as long as it is a route for supplying / draining a liquid capable of changing the underground impedance. There are no restrictions. In addition, in this example, the water leak detection device shown in FIG.
Not limited to this, the leak detection method of this example may be performed using other measuring equipment. However, for the measurement,
It is preferable to use an AC signal for measurement because the influence of the electrolytic effect can be avoided. Furthermore, the impedance value with respect to the surroundings of the water pipe may be constantly monitored. Further, there is no limitation on the setting of the time from the stopped state to the supply state when switching the state in which the water supply is stopped to the state in which the water is supplied to the water guide path and comparing the impedance values.

[0034]

As described above, in the present invention, when a water leak occurs in the water conduit in the ground, the impedance value (resistance value) in the ground around the water leak position is the impedance value in a state where there is no water leak. The feature is that the presence or absence of water leakage at the position is detected based on the fact that it becomes lower than Therefore, according to the present invention, since the water leakage is determined by the change in the underground impedance due to the water leakage state, it is possible to reliably detect the presence or absence of the water leakage and the position thereof regardless of the skill and sense of the operator.

When the supply of water to the water conduit is forcibly changed and the impedance values before and after the change are compared, the leakage can be detected easily and reliably without constantly monitoring the impedance value. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing a basic configuration of a water leak detection device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a water leak detection method according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a water leak detection method according to a second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Leakage detection device 13 ... Thyristor 14 ... 1st transformer 17 ... 2nd transformer 10 ... Measurement signal generation part 20 ... Rectification part 30 ... Amplification part 40. · detection result display unit 41 ... current detector L _11, L ₂₁ ... water pipe (water guide path) S _11, S ₂₁ ··· Faucets _{A 1, B 1, C 1} , A 2, B ₂ , C ₂ , D ₂ , E ₂ , F
₂ ... Points A ₁₁ , B ₁₁ , A ₂₁ , B ₂₁ ... Bifurcations D ₁₁ , D ₁₂ , D ₂₁ , D ₂₂ ... Faucet (electrode body) D ₁₃ , D ₂₃ , D ₂₄ , D ₂₅ , D ₂₆ ... Electrode rod (electrode body)

Claims (3)

[Claims] 1. When a water leak occurs in a water conduit in the ground, the impedance value in the ground around the water leak position is lower than the impedance value in a state without water leak, and the position of the position is reduced. A method for detecting water leakage, which comprises detecting the presence or absence of water leakage in. 2. The two electrode bodies according to claim 1, wherein the two electrode bodies embedded at the positions where the presence or absence of water leakage should be detected are used to stop the water supply to the water guiding path between the electrode bodies. After measuring the first impedance value as the impedance value in the absence of water leakage,
The second impedance value between the electrode bodies is measured in a state where water is supplied to the water guide path, and the water guide path is provided at any position between one side and the other side of the electrode body. When water is leaking to the electrode, the second impedance value becomes lower than the first impedance value, and therefore the presence or absence of water leakage between the electrode bodies is detected. . 3. A water leakage detection device used for carrying out the water leakage detection method as defined in claim 1 or 2, comprising: input terminals to which the electrode bodies are respectively connected, and an impedance value between the input terminals. In response to the change, the drive current converted from the commercial power supply by the thyristor and the first transformer is changed and supplied to the second transformer,
A measurement signal generator that outputs an AC signal from the second transformer, a rectifier that rectifies the AC signal, and an amplifier that amplifies the level of the signal rectified by the rectifier based on an externally set amplification degree. And a detection result display unit including a movable coil driven based on the signal amplified by the amplification unit and a pointer that is displaced by the movable coil to a position corresponding to the impedance value. Detection device.