JP2000180287A - Monitoring device for leakage of fluid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify constitution by discriminating presence of leakage when a low of fluid in a fluid feed passage continues for a fixed term, based on the detected result of a flow sensor provided in the fluid feed passage and detecting presence of fluid. SOLUTION: A flow sensor 12 provided on the optional position in a gas feed pipe 3 comprises a film heater part and a film detecting part, and by heating the film heater part, the flow of fluid can be detected as the increased portion of the resistance value of the film detecting part. A monitoring part 13 provided outside the gas feed pipe 3 is constituted of a main control part, a display part, and the like. The flow sensor 12 detects presence of gas flow in the gas feed pipe 3 and outputs to the monitoring part 13. When gas leakage is generated even at using no gas, the flow sensor 12 outputs a signal of presence of gas flow to the monitoring part 13. Assuming that gas is not continuously consumed for 720 hours ordinarily, and when the detected result of presence of gas leakage continues for 720 hours, the monitoring part 13 discriminates presence of gas leakage, and displays the presence of gas leakage on a display part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid leakage monitoring device, and more particularly to a fluid leakage monitoring device that does not use a bypass flow path.

[0002]

2. Description of the Related Art For example, in a gas facility, gas is supplied from a gas supply facility to a gas consuming facility in a general household via a gas supply pipe. In this case, a so-called microcomputer gas meter is attached to a gas consuming facility (a pipe connected to a gas supply pipe and a gas consuming apparatus) of each household, and a gas flow rate flowing through the gas pipe is measured. There must always be time to use no gas once
When a predetermined gas flow rate or more is detected continuously for 0 days, it is determined that there is a gas leak and an alarm is issued.

However, the gas supply pipe connecting the gas supply equipment to the gas consumption equipment is buried underground,
When a small gas leak occurs in the gas supply pipe, it is necessary to perform a boring operation to check the gas leak.

[0004] In this case, the microcomputer gas meter applied to the gas pipes of ordinary households described above is applied to directly detect the state of the gas flow in the gas supply pipe because the flow rate of the gas supply pipe is very large. Can not do. For this reason, a special gas meter must be used, and there is a problem that the cost is increased.

Therefore, conventionally, utility model registration No. 25028
As described in Japanese Patent No. 40, a small-volume bypass pipe is provided in a pressure regulator provided in a gas supply pipe (main pipeline) through which a large amount of gas flows, and an outlet from the pressure regulator is provided in this bypass pipeline. A pipe leak detector equipped with a small pressure regulator that sets the pressure slightly higher and a gas meter with the small leak detection function (microcomputer meter described above) that determines and displays leakage when the gas flow does not stop for a certain period of time It has been known.

That is, as shown in FIG.
Pressure regulation in the middle of a gas supply pipe 107 for supplying gas from a gas supply source 103, which is a combination of a gas cylinder 101 and a switch 102, to a gas consuming apparatus and a piping portion of each household 104, and a gas consuming facility 106 including a microcomputer gas meter 105. And a pressure regulator 108
A bypass pipe 109 is provided for connecting the inlet side and the outlet side of the fuel cell. A small pressure regulator 110 having an outlet pressure slightly higher than that of the pressure regulator 108 is provided in the bypass pipe 109, and a gas meter with a small leak detection function is provided. 111 is provided.

[0007] This pipe leak detecting device is designed such that when the gas flow in the gas supply pipe 107 almost stops at night or at midnight, the pressure regulator 10
Since the outlet pressure of the small pressure regulator 110 is slightly higher than that of 8, the gas is switched so as to flow only through the bypass line 109, and it is determined whether or not a very small amount of gas is flowing through the bypass line 109. Gas meter with detection function 1
11 is detected.

[0008] Although the construction is exactly the same as that of the pipe leakage detecting device, as described in Japanese Patent No. 2587108, a gas supply pipe connecting a gas supply source and gas consuming equipment has one pressure regulator. And a bypass gas flow path connecting the inlet side and the outlet side of the one pressure regulator is provided, and the other pressure regulator having a higher regulation pressure than the one pressure regulator is provided in the bypass gas flow path. Along with the provision of the micro-leakage detection means, when the gas supply pipe has a low flow rate, the gas flows only into the bypass gas flow path,
There is also known a gas flow channel leak monitoring system in which the micro leak detection means detects a micro flow rate in a bypass gas flow channel.

[0009]

However, in the above-mentioned conventional pipe leak detecting device or gas flow channel leak monitoring system, in any case, the existing microcomputer gas meter is diverted to prevent the gas leak from the gas supply pipe. Therefore, a bypass line must be connected to a gas supply pipe through which a large amount of gas flows, and a small pressure regulator and a gas meter must be attached to the bypass line.

[0010] Therefore, the work of mounting the bypass line, the small pressure regulator and the gas meter is troublesome, the number of parts is increased and the cost is increased, and a large installation place must be secured in order to increase the size of the device. Must.
In addition, providing a bypass pipe separately from the gas supply pipe increases the number of conduits through which the gas passes, and accordingly increases the possibility of leakage.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a leak detecting device capable of detecting a leak of a fluid with a simple configuration.

[0012]

According to a first aspect of the present invention, there is provided a fluid leakage detecting apparatus for connecting a fluid supply source to a fluid consuming facility and / or the consuming facility. A flow sensor for detecting the presence or absence of a fluid provided in the fluid supply path, and a flow of the fluid in the fluid supply path based on a detection result of the flow sensor. And a determining means for determining that there is a leak when a predetermined period of time has elapsed.

According to a second aspect of the present invention, in the fluid leakage monitoring device according to the first aspect of the present invention, the flow sensor is provided downstream of a pressure adjusting means provided in the fluid supply path.

According to a third aspect of the present invention, in the fluid leakage monitoring device according to the second aspect, the flow sensor is provided downstream and upstream of the pressure adjusting means.

According to a fourth aspect of the present invention, in the fluid leakage monitoring device according to any one of the first to third aspects, the fluid supply source is a gas supply source, and the fluid consumption equipment is a gas consumption device. 720, wherein the fluid supply path is a gas supply pipe, and the determining means checks the detection result of the flow sensor one or more times per unit time to determine whether or not there is a fluid flow. When there is a gas flow for a continuous time, it is determined that there is a leak.

[0016]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an overall explanatory diagram of a gas facility provided with a gas leak monitoring device according to a first embodiment of the present invention. In this gas facility, a gas supply source 1 as a fluid supply source and a gas consumption facility 2 as a fluid consumption facility are connected via a gas supply pipe 3 as a fluid supply path. The gas supply source 1 includes a plurality of gas cylinders 4 and a switch 5 for switching the gas cylinders 4 for supplying gas to the gas supply pipe 3. The gas consuming equipment 2 includes, for example, a gas consuming appliance of each home 6, a pipe 7 for distributing and supplying gas from the gas supply pipe 3 to each home 6, and a gas meter 8 attached to the pipe 7.

As shown in FIG. 2, the gas leak detecting device according to the present invention applied to such a gas facility has an arbitrary portion of the gas supply pipe 3 (this is referred to as a "detecting portion 11"). And a flow sensor 12 for detecting the presence or absence of a gas flow in the gas supply pipe 3 and a detection signal from the flow sensor 12 provided outside the gas supply pipe 3 to determine gas leakage. And a monitoring unit 13 including a determination unit for determining whether or not to perform the determination.

The flow sensor 12 has, for example, a membrane heater section and a membrane detection section bridged in a cantilever or cantilever manner on a through hole or a cavity formed in a substrate, and heats the membrane heater section. In this way, when the fluid to be measured flows, the temperature of the membrane detecting section rises due to heat conduction in accordance with the flow rate, and if the membrane detecting section is a resistor having a positive temperature coefficient, the flow rate is reduced. It can be detected as an increase in the value. Such a flow sensor 12 is specifically described in, for example, JP-A-6-66613.

As shown in FIG. 3, the monitoring unit 13 comprises a main control unit 14 comprising a microcomputer or the like which also serves as a discriminating means for controlling the whole control, and a warning for displaying an alarm when it is determined that there is a leak. Display unit 15 and buzzer 16; communication control unit 17 for transmitting through a communication line; main control unit 1
Operation unit 1 for inputting various setting information to 4
8 is provided.

Next, the operation of the leak detecting device thus configured will be described with reference to FIG. First, when gas is used in the gas consuming equipment 2, the gas is supplied from the gas supply source 1 to the gas consuming equipment 2 through the gas supply pipe 3, so that a gas flow occurs in the gas supply pipe 3. I have. Therefore, at this time, the flow sensor 12 provided in the gas supply pipe 3 detects a state that the gas flows in the gas supply pipe 3 and outputs the detected state to the monitoring unit 13.

Further, gas is no longer used in all of the gas consuming equipment 2 and the gas consuming equipment 2 and the gas supply pipe 3
If there is no gas leak at the above, no gas is supplied from the gas supply source 1 and the gas flow in the gas supply pipe 3 stops. Therefore, at this time, the flow sensor 12 provided in the gas supply pipe 3 detects a state in which there is no gas flow in the gas supply pipe 3 and outputs the state to the monitoring unit 13.

On the other hand, although the gas is no longer used in all the gas consuming equipment 2, if a gas leak occurs in the gas consuming equipment 2 and / or the gas supply pipe 3, the gas is supplied from the gas supply source 1. Is supplied, a gas flow is generated in the gas supply pipe 3. Therefore, at this time, the flow sensor 12 provided in the gas supply pipe 3 detects a state that the gas flows in the gas supply pipe 3 and outputs the detected state to the monitoring unit 13.

Therefore, referring to FIG. 4, the main control unit 14 of the monitoring unit 13 measures a time interval (here, one hour) for checking the detection signal from the flow sensor 12. Is set / started, and when the timer expires, the detection signal from the flow sensor 12 is taken in, and it is determined whether or not the detection signal indicates that there is a gas flow.

If there is a gas flow, the counter is incremented (+1), and then it is determined whether or not the count value of the counter is "720". At this time, if the count value of the counter is not "720", the process returns to the process of setting / starting the timer. When there is no gas flow, a process of resetting the count value of the counter is performed, and the process returns to the process of setting / starting the timer.

As described above, the detection signal of the flow sensor 12 is checked every hour. If the detection signal indicates that there is a gas flow, the counter is incremented (+1), and if there is no gas flow, the counter is reset. Thus, when the detection result of the presence of gas flow by the flow sensor 12 continues for 720 hours (30 days), the count value of the counter becomes “720”, so it is determined that there is gas leakage, and the presence of gas leakage is displayed on the display unit. 15 or an alarm is issued by a buzzer 16 and a determination result is transmitted to a central management unit (not shown) through the communication control unit 17.

That is, normally, 720 hours (30 days)
Assuming that gas is not consumed continuously regardless of day and night, if there is a continuous gas flow for 720 hours, it can be determined that a gas leak has occurred. As described above, when there is a continuous gas flow for a certain period, it is treated as gas leakage.

As described above, the flow sensor provided in the gas supply path for detecting the presence / absence of the gas and the leakage when the gas flow in the gas supply path continues for a predetermined period based on the detection result of the flow sensor. A bypass pipe for bypassing a gas supply pipe, a branch part for bypassing the bypass pipe, a microcomputer meter for detecting gas flow in the bypass pipe, pressure adjustment Since various components such as a machine are not required, the configuration is simplified, the cost is reduced, and gas leaks in the gas supply pipe can be accurately detected.

In the above-described embodiment, the leakage is determined on the assumption that the gas should not be consumed continuously for a certain period of time. Appliances that continue to consume are beginning to be used.

Therefore, when the present invention is applied to a gas facility using such a gas consuming appliance, the main control unit 14 uses the gas consumption per unit time of the appliance that continuously consumes gas on a 24-hour basis as a reference amount. (For example, it can be set from the operation unit 18), and the flow sensor 1
2. If the amount of gas flow is detected in step 2 and the amount of gas flow in the gas supply pipe 3 does not fall below the reference amount at least once every 30 days, it is determined that there is a gas leak. Monitoring can be performed.

Since a gas flow may be generated due to a temperature change, the sensitivity of the flow sensor is set so that the gas flow due to the temperature change is not detected as a gas flow.
Alternatively, when the detection signal from the flow sensor is checked, the detection signal is checked a plurality of times, and if there is no gas flow once or several times, a process of making the check result at that time no gas flow is performed. You can also.

Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. This embodiment is a gas facility in which a pressure regulator 10 is provided in the middle of a gas supply pipe 3.
A flow sensor 12 is provided at an arbitrary position (hereinafter referred to as a “detection unit 10”) on the downstream side of the pressure regulator 10, that is, in the gas supply pipe 3 between the pressure regulator 10 and the gas consuming facility 2.
This is an example in which is provided.

In this way, if a minute leak occurs downstream of the pressure regulator 10, it can be detected.

Next, a third embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. This embodiment is a gas facility in which a pressure regulator 10 is provided in the middle of a gas supply pipe 3.
Arbitrary locations (referred to as "detection unit 10") in two locations on the upstream and downstream sides of the pressure regulator 10, that is, in the gas supply pipe 3 between the pressure regulator 10 and the gas supply source 1. And a flow sensor 12 at an arbitrary position (hereinafter referred to as a “detection unit 10”) in the gas supply pipe 3 between the pressure regulator 10 and the gas consuming equipment 2. This is an example in which a detection signal of the flow sensor 12 is input to the monitoring unit 13.

In this way, even when the pressure regulator 10 is provided, it is possible to detect a minute leak occurring upstream or downstream of the pressure regulator 10.

Next, application of the present invention to existing gas equipment will be described with reference to FIG. That is, the sensor-equipped pipe 21 in which the flow sensor 12 of the detection section is incorporated is formed, and is attached in the middle of the existing gas supply pipe 3, so that the flow sensor 12 can be easily incorporated into the existing gas supply pipe 3. it can. When the flow sensor 12 and the control unit (monitoring unit) 13 are connected, a leakage monitoring device can be easily configured.

Next, the flow sensor 1 into the gas supply pipe 3
2 will be described with reference to FIG. The flow sensor 12 is rotatably supported by a support member 22 provided in the gas supply pipe 3, and when there is no gas flow or when there is a small gas flow, the flow sensor 12 moves in the gas flow direction as shown in FIG. The detection surfaces are opposed to each other, and when the gas flow is large, it is held in a substantially horizontal or inclined state as shown in FIG.

In this manner, when the flow rate is small, the sensitivity is increased, and the gas flow can be accurately detected. When the flow rate is large, the accuracy of sensing can be increased without obstructing the gas flow. In order to make the sensor displaceable in this way, in addition to the above example, for example, an elastic member may be used for the sensor mounting portion so that the sensor can be displaced by pressure due to the flow rate.

In the above embodiment, the present invention is applied to the monitoring of the leakage of gas as a fluid.
The present invention can also be applied to leakage monitoring of gas, liquid, and the like other than gas.

[0039]

As described above, according to the fluid leakage detecting device of the first aspect, the fluid supply path connecting the fluid supply source and the fluid consuming equipment and / or the fluid leakage in the consuming equipment. A flow sensor for detecting the presence or absence of a fluid provided in the fluid supply path, wherein the flow of the fluid in the fluid supply path is continuously performed for a predetermined period based on a detection result of the flow sensor. Since it is provided with a discriminating means for discriminating that there is a leak when the fluid is leaked, the leak of the fluid can be detected with a simple configuration.

According to the fluid leakage detecting device of the second aspect,
2. The fluid leakage monitoring device according to claim 1, wherein the flow sensor is provided on a downstream side of a pressure adjusting unit provided in the fluid supply path. Fluid can be detected at the same time.

According to the fluid leakage detecting device of the third aspect,
In the fluid leakage monitoring device according to claim 2, since the flow sensor is configured to be provided on the downstream side and the upstream side of the pressure adjusting unit, even when the pressure adjusting unit is provided,
It is possible to detect leakage of the fluid upstream or downstream.

According to the fluid leakage detecting device of the fourth aspect,
The fluid leakage monitoring device according to any one of claims 1 to 3, wherein the fluid supply source is a gas supply source, the fluid consumption facility is a gas consumption facility, and the fluid supply path is a gas supply pipe. The determination means checks the detection result of the flow sensor once or more times per unit time to determine whether there is a gas flow, and determines that there is a leak when there is a continuous gas flow for 720 hours. With this configuration, it is possible to detect a minute leak of gas in the gas equipment.

[Brief description of the drawings]

FIG. 1 is an overall explanatory diagram of a gas facility provided with a gas leak monitoring device according to a first embodiment of the present invention.

FIG. 2 is an enlarged explanatory diagram of a main part of a detection unit in FIG. 1;

FIG. 3 is a block diagram of the monitoring unit.

FIG. 4 is a flowchart for explaining the operation of the monitoring device;

FIG. 5 is an overall explanatory diagram of a gas facility provided with a gas leak monitoring device according to a second embodiment of the present invention.

FIG. 6 is an overall explanatory diagram of a gas facility provided with a gas leak monitoring device according to a third embodiment of the present invention.

FIG. 7 is an explanatory diagram illustrating attachment of a flow sensor to existing equipment.

FIG. 8 is an explanatory view for explaining a structure for attaching a flow sensor to a gas supply pipe.

FIG. 9 is an explanatory diagram of a conventional leak monitoring device.

[Explanation of symbols]

1 gas supply source, 2 gas consumption equipment, 3 gas supply pipe,
10: pressure regulator, 12: flow sensor, 13: monitoring unit.

Claims (4)

[Claims] 1. A fluid supply path for connecting a fluid supply source to a fluid consuming facility and / or a leak monitoring device for monitoring fluid leakage in the consuming facility, wherein the fluid is provided in the fluid supplying path. A flow sensor for detecting the presence or absence of
A fluid leakage monitoring device comprising: a determination unit configured to determine that there is a leak when the flow of the fluid in the fluid supply path has continued for a predetermined period based on the detection result of the flow sensor. 2. The fluid leakage monitoring device according to claim 1, wherein the flow sensor is provided downstream of a pressure adjusting unit provided in the fluid supply path. 3. The fluid leakage monitoring device according to claim 2, wherein the flow sensor is provided downstream and upstream of the pressure adjusting means. 4. The fluid leakage monitoring device according to claim 1, wherein the fluid supply source is a gas supply source, the fluid consumption equipment is a gas consumption equipment, and the fluid supply path is A gas supply pipe, wherein the determination means checks the detection result of the flow sensor one or more times per unit time to determine whether there is a fluid flow, and determines whether the gas flow is continuous for 720 hours. A fluid leakage monitoring device characterized in that it is determined that there is leakage at a certain time.