JPH08200598A - Gas pipe leak detection system - Google Patents

Abstract

(57) [Summary] [Purpose] A gas leak from a gas meter to each gas appliance can be continuously detected, and the location of the leak can be quickly found even in a complicatedly branched gas pipe. Provide a leak detection system for gas piping. [Structure] It is installed at a plurality of locations along the gas flow path in the gas pipe 3 from the gas meter 2 to each of the gas appliances 4, 5, and 6, and a detection sound of a predetermined frequency different from each other corresponding to each location is provided. A group of whistles 7 generated by the gas flow
a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i
And a detection means 14 for continuously detecting gas leakage by discriminating the piping areas A to F where there is a leak location based on an electric signal from the microphone 13 that collects the detection sound generated by these. Leak detection system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas pipe leak detection system for continuously detecting a gas leak from a gas pipe from a gas meter to each gas appliance by identifying a pipe area where the gas leaks.

[0002]

2. Description of the Related Art For example, in a general household to which city gas is supplied, a large number of gas appliances such as a gas water heater, a gas range, a gas rice cooker, a gas stove, a gas warm air heater, and a gas bath are installed in a kitchen, a living room, It is installed in the required places such as bedrooms and bathrooms. The gas pipe from the gas meter to each of these gas appliances is routed under the floor or inside the wall so as not to get in the way or obstruct the eyes, and is often routed in a complicated manner.

The gas pipe from such a gas meter to each gas appliance may be deteriorated or damaged during the remodeling work of a house. In such a case, gas leakage occurs and gas poisoning or gas poisoning occurs. Since it causes an explosion accident, it has been conventionally demanded to detect a gas leak as soon as possible and to treat the leaked place in terms of safety management of gas supply.

Generally, as means for detecting the position of gas leak in the gas pipe, there is a method of applying soap water to the outer peripheral surface of the gas pipe and detecting the presence or absence of gas leak by the presence or absence of bubbles. A method of using a leak detector, a method of detecting the presence or absence of gas leak by measuring the holding state of the pressure inside the tube after sealing the gas tube, and the like are conventionally known in general.

[0005]

By the way, the above-mentioned method of applying the soapy water to the outer peripheral surface of the gas pipe and the method of measuring the holding state of the pipe internal pressure after sealing the gas pipe are described below the floor or inside the wall. It is difficult to apply to the gas pipe routed to, and when adopting this method by force, all of the floor and walls along the gas pipe must be destroyed to expose the entire gas pipe, It takes a lot of time and effort and is not practical.

On the other hand, in the method using the gas leak detector, it is possible to detect the presence or absence of the gas leak without breaking down the floor or the wall, but if the leaked gas is widely diffused, the gas leak location can be specified. Difficult to do.

Therefore, conventionally, even if a gas leak from the gas pipe from the gas meter to each gas appliance is found, it takes a lot of time to find the location of the gas leak,
There was also the possibility of an unexpected gas accident due to a delay in leak repair.

Therefore, the present invention can continuously detect a gas leak in a gas pipe from a gas meter to each gas appliance, and can quickly find a leak location even in a gas pipe that branches in a complicated manner. An object is to provide a leak detection system for piping.

[0009]

As a means for achieving this object, the present invention is a system for detecting a gas leak from a gas pipe from a gas meter to each gas appliance, wherein a gas flow path in the gas pipe is provided. Based on the detection sound generated by the group of sounding means, which is installed at a plurality of locations along each of the sounding means and which generates detection sounds of mutually different predetermined frequencies corresponding to the respective installation locations by the gas flow, The present invention is characterized by including a detection means for continuously detecting a gas leak by discriminating a piping area having a leak.

Here, the group of sounding means is a group of whistle devices that generate a detection sound by a gas flow, and the detection means includes a microphone that collects the detection sound from the group of whistle devices and outputs it as an electric signal. The present invention is also characterized by continuously detecting a gas leak by discriminating a piping area having a gas leak based on an electric signal from the microphone.

[0011]

According to the gas pipe leakage detection system of the present invention which employs such means, when the use of all gas appliances is stopped and each terminal of the gas piping from the gas meter to each gas appliance is blocked, the gas When there is no gas leak in the pipe, the gas flow in the gas pipe disappears, and the group of sound generating means stops generating the detection sound.

If there is a gas leak in the gas pipe, a gas flow from the gas meter to the leak point is generated in the gas pipe, so that a group of sound generators installed in the gas flow path upstream from the leak point is generated. The means generate mutually different detection sounds at a predetermined frequency corresponding to each installation location. Therefore, the detection means identifies the sounding means that is generating the detection sound on the upstream side that is closest to the leaked point and the sounding means that is not generating the detection sound on the downstream side that is closest to the leaked point, and Detect gas leaks in the gas pipes by determining that there is a leak point in the piping area between them.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be specifically described below with reference to the drawings. In FIG. 1 showing the basic configuration of the leak detection system for gas piping, reference numeral 1 is a supply pipe drawn into each customer from a conduit line under the road (not shown), reference numeral 2 is a gas meter connected to the supply pipe 1, and reference numeral 3 Indicates the indoor pipes routed to the interior of the consumer through the gas meter 2, and to the indoor pipes 3, the water heater 4, the gas stove 5, and the gas stove 6 that are installed indoors as gas appliances are branched. It is connected through the pipes 3a, 3b, 3c.

Here, inside the indoor pipe 3, a group of whistle devices 7 which generate a detection sound of a different predetermined frequency by a gas flow flowing therethrough by a whistle mouth or a reed.
a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i
Is installed as a group of sounding means. That is, for example, a whistle device 7a that generates a detection sound of 100 Hz is installed at an upstream position of the indoor pipe 3, and a whistle device 7b that generates a detection sound of 201 Hz is installed at an upstream position of the branch pipe 3a. A whistle device 7c that generates a detection sound of, for example, 301 Hz is installed at a position downstream of the pipe 3a. Similarly,
A whistle device 7d that generates a detection sound of, for example, 401 Hz is provided at a position immediately downstream of the branch position of the branch pipe 3a in the indoor pipe 3.
Is installed at the upstream position of the branch pipe 3b, for example, 501H.
The whistle device 7e for generating the detection sound of z is installed, and the branch pipe 3
For example, a whistle device 7f that generates a detection sound of 601 Hz is installed at a downstream position of b. Similarly, a whistle device 7g that generates a detection sound of 701 Hz, for example, is installed immediately downstream of the branch position of the branch pipe 3b in the indoor pipe 3, and a detection sound of 801 Hz is generated at the upstream position of the branch pipe 3c. A whistle device 7h for generating sound is installed, and a whistle device 7 for generating a detection sound of, for example, 901 Hz is provided at a position downstream of the branch pipe 3c.
i is installed.

The group of whistle devices 7a, 7b, 7c, 7
d, 7e, 7f, 7g, 7h, and 7i are installed in advance in a cheese or an elbow or a socket that is a connection joint of the indoor pipe 3, and the whistle device 7a is a whistle device 7b, 7d.
It is installed corresponding to the piping area A between the whistle device 7b
Is installed corresponding to the piping area B between the whistle device 7c. Similarly, the whistle device 7d is installed corresponding to the piping area C between the whistle devices 7e and 7g, and the whistle device 7e is installed corresponding to the piping area D between the whistle device 7f. Similarly, the whistle device 7g is installed corresponding to the piping area E between the whistle device 7h and the whistle device 7h.
It is installed corresponding to the piping area F between the and.

On the other hand, in the gas meter 2, the group of whistle devices 7a, 7b, 7c, 7d, 7e, 7f, 7g,
A microphone 13 that collects the detection sound generated by 7h and 7i through the indoor pipe 3 and outputs it as an electric signal is incorporated. Further, a control unit 14 which constitutes a detection means for detecting the gas leak by specifying the piping areas A to F based on the electric signal from the microphone 13 is also incorporated in the gas meter 2.

As shown in FIG. 2, the control unit 14 serves as a processing unit for an electric signal output from the microphone 13 which collects a detection sound, and amplifies the electric signal. Bandpass filter 16 and bandpass filter 1 that remove noise
It has an A / D converter 17 for converting an analog signal of the detection sound passed through 6 into a digital signal.

Further, the control unit 14 frequency-analyzes the detection sound of the digital signal converted by the A / D converter 17 to create detection sound analysis data for each frequency, and the group of whistles. Devices 7a, 7b, 7
c, 7d, 7e, 7f, 7g, 7h, 7i individually detects whistle sound generated reference sound data for each whistle device, and the signal analysis unit 18 The whistle devices 7a, 7b, 7c, 7 which generate the detection sound by collating the detection sound analysis data with the detection sound reference data from the detection sound reference data memory 19 for each whistle device.
d, 7e, 7f, 7g, 7h, 7i are identified, and based on the identification result, the piping area A where the gas leakage occurs
Leakage area determination unit 20 for determining F, an alarm device 22 for receiving a determination signal from the leakage area determination unit 20 to warn the occurrence of gas leakage, and a determination signal from the leakage area determination unit 20 for leakage Areas A to F where
And a display unit 24 for displaying a map on the LCD or the like.

Here, the leakage area discriminating unit 20 is arranged so that the whistle devices 7b and 7d are activated when the whistle device 7a is producing a detection sound.
Is not producing a detection sound, whistle device 7a and whistle device 7
It is determined that a gas leak is occurring in the piping area A between the whistle device 7b and 7d, and if the whistle device c is not producing the detection sound when the whistle device 7b is producing the detection sound, the whistle device 7b It is determined that gas leakage has occurred in the piping area B between the whistle device c and the whistle device c. Further, when the whistle device 7d is producing a detection sound and the whistle devices 7e and 7g are not producing a detection sound, a piping area C between the whistle device 7d and the whistle devices 7e and 7g is provided.
If the whistle device 7e is producing a detection sound and the whistle device 7f is not producing a detection sound, the pipe area between the whistle device 7e and the whistle device 7f is determined. It is determined that gas leakage has occurred in D. Furthermore, when the whistle device 7g is generating a detection sound, the whistle device 7h
7g and whistle device 7h if is not generating a detection sound
It is determined that gas leakage is occurring in the piping area E between the whistle device 7h and the whistle device 7h when the whistle device 7i is not producing the detection sound when the whistle device 7h is producing the detection sound. It is determined that gas leakage has occurred in the piping area F between 7i and 7i.

Next, the operation of the present embodiment constructed as above will be described. Among the gas appliances installed after the gas meter 2, for example, when the water heater 4 and the gas stove 6 are in use and the gas stove 5 is not in use, the piping areas A, B, C, E of the indoor pipe 3 are shown. , F, a gas flow is generated, and basically no gas flow is generated in the piping area D. Therefore, a group of other whistle devices 7a, 7b, 7c, 7d, 7g excluding the whistle devices 7e, 7f, 7h and 7i generate a detection sound. Here, when a gas leak occurs in the branch pipe 3b connected to the gas stove 5, that is, in the piping area D, a gas flow is generated from the upstream position of the branch pipe 3b to the gas leak point. Also generates a detection sound, but the whistle device 7f does not generate a detection sound.

Under such circumstances, a group of other whistle devices 7a, 7b, 7c, 7d, 7e, 7 excluding the whistle device 7f.
g, 7h, 7i frequency 100Hz, 201H
z, 301Hz, 401Hz, 501Hz, 701H
The detection sounds of z, 801 Hz, and 901 Hz are transmitted through the indoor pipe 3 and collected by the microphone 13 in the gas meter 2. In addition, since the detection sound hardly leaks from the indoor pipe 3 to the outside, there is no fear of being offensive to the ears.

Each detection sound from the group of whistle devices 7a, 7b, 7c, 7d, 7e, 7g, 7h, 7i picked up by the microphone 19 is amplified by the amplifier 15 as an electric signal in the control unit 14 to be bandpassed. The noise is removed by the filter 16 and the A / D converter 17
Is converted into a digital signal by.

Here, the digital signal from the A / D converter 17 is as shown in the control flowchart of FIG.
The signal is read as a detection sound signal by the signal analysis unit 18 (step S1), and is frequency-analyzed there.
Hz, 301Hz, 401Hz, 501Hz, 701H
Analysis data of each detection sound of z, 801 Hz, and 901 Hz is created (step S2).

In the subsequent step S3, the created 100
Hz, 201Hz, 301Hz, 401Hz, 501H
The analysis data of each detection sound of z, 701 Hz, 801 Hz, and 901 Hz is collated with the detection sound reference data stored in the detection sound reference data memory 19 for each whistle device by the leakage area determination unit 20. Then, based on this collation result, the leakage area determination unit 20 causes the whistle devices 7a, 7b, 7c, 7d, 7e, 7g, 7h, 7i that are generating the detection sound.
Is specified (step S4).

Here, the leakage area discriminating section 20 determines that the whistle device 7e does not generate the detection sound even though the whistle device 7e generates the detection sound.
It is determined that the gas leakage has occurred in the piping area D between the area f and the area f (step S5). Then, according to the determination result, the alarm device 22 warns that a gas leak has occurred (step S6), and the display unit 24 displays a map that a gas leak has occurred in the piping area D (step S7).

As described above, according to the gas pipe leakage detection system of the present embodiment, for example, when a gas leak occurs in the middle of the branch pipe 3b to which the gas stove 5 is connected, the gas stove 5 may be unused. When the whistle device 7e generates the detection sound and the whistle device 7f does not generate the detection sound, the alarm device 22 warns that the gas leakage has occurred, and the gas leakage point is displayed as the piping area D by the display unit 24. The map is displayed.

Similarly, at midnight, the water heater 4,
When all of the gas stove 5 and the gas stove 6 are stopped, for example, when a gas leak occurs in the piping area C, the whistle device 7d generates a detection sound on the upstream side closest to the leak point, and the leak point is detected. Whistle devices 7e, 7 at the nearest downstream side
Since g does not generate any detection sound, the fact that gas leakage has occurred in the piping area C is displayed on the display unit 24 as a map, and at the same time, the alarm device 22 gives an alarm. The same applies when the gas leakage occurs in any of the piping areas A to F. Therefore, it is possible to continuously detect the occurrence of a leak in the gas pipe, and it is possible to quickly find the leak location even in the case of a gas pipe that branches in a complicated manner.

Here, the gas appliance leak detection system of this embodiment is inexpensive and does not require a power source.
It is cost effective because it has a structure for detecting the occurrence of gas leakage in the indoor pipe 3 by 7b, 7c, 7d, 7e, 7f, 7g, 7h, and 7i. Further, in the past, when gas leakage was a concern, the pressure in the section where the gas was once shut off was detected, but in the leak detection system for gas appliances of the present embodiment, the gas leaks without shutting off the gas. The position of the place can be detected.

In this embodiment, the gas meter 2 is provided with the alarm device 22 for alarming the occurrence of gas leakage and the display unit 24 for displaying a map of the location of gas leakage, but these are easily noticeable. It may be installed at an appropriate place indoors.

Further, in the present embodiment, as the gas pipe, the branch system pipe in which the respective branch pipes 3a, 3b, 3c are branched from the indoor pipe 3a is targeted, but the present invention is applicable to a plurality of gas appliances connected to each gas appliance. The same can be applied to a header-type gas pipe in which the gas pipe is collected in the header, and in that case, the group of whistle devices is installed at the outlet of the header, the socket, the calan, or the like.

Further, in this embodiment, a group of whistle devices 7
a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i
The frequency of the detection sound generated is 100Hz, 201H
z, 301Hz, 401Hz, 501Hz, 601H
Although z, 701 Hz, 801 Hz, and 901 Hz are given, these are merely examples and other frequencies may be set.

Furthermore, the number and types of the circuits and members constituting the control unit 14 are not limited to those in this embodiment, but may be realized by software.

[0033]

As described above, according to the present invention, when the use of all gas appliances is stopped and each terminal of the gas piping from the gas meter to each gas appliance is closed, there is no gas leakage in the gas piping. The group of sounding means stops the generation of the detection sound when the gas flow in the gas pipe disappears, but if there is a gas leak in the gas pipe, the gas flow from the gas meter to the leak point in the gas pipe. When a sound is generated, a group of sounding means installed in the gas flow path upstream from the leaking site generate mutually different detection sounds at predetermined frequencies corresponding to the respective installation sites. So the detection method is
Identify the sounding means that is producing the detection sound at the upstream side closest to the leak point and the sounding means that is not producing the detection sound at the downstream side closest to the leak point, and install them in the piping area between both sound producing means. Detect gas leaks in gas pipes by determining that there is a leak location.

Therefore, according to the present invention, it is possible to continuously detect a gas leak in the gas pipe, and at this time, the pipe area in which the gas leak occurs is discriminated. Also, the leak location can be found quickly. As a result, it is only necessary to carry out repairs on the leaked portion, which enables low cost and early repairs.

[Brief description of drawings]

FIG. 1 is a block configuration diagram showing an overall configuration of an embodiment of a gas pipe leakage detection system according to the present invention.

FIG. 2 is a block diagram of a control unit according to an embodiment.

FIG. 3 is a control flowchart showing a process of a control unit in one embodiment.

[Explanation of symbols]

1 Supply Pipe 2 Gas Meter 3 Indoor Pipe 3a, 3b, 3c Branch Pipe 4 Water Heater 5 Gas Stove 6 Gas Stove 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7
i Whistle device 13 Microphone 14 Control unit 15 Amplifier 16 Bandpass filter 17 A / D converter 18 Signal analysis unit 19 Whistle device-specific detection sound reference data memory 20 Leakage area discrimination unit 22 Alarm device 24 Display unit

Claims (2)

[Claims] 1. A system for detecting a gas leak from a gas pipe from a gas meter to each gas appliance, the system being installed at a plurality of locations along a gas flow path in the gas pipeline, corresponding to each location. Based on a group of sounding means that generate detection sounds of mutually different predetermined frequencies by the gas flow, and the detection sound generated by the one group of sounding means, the pipe area where the gas leaks is discriminated and the gas leakage is continuously performed. A leak detection system for gas piping, comprising: a detection means for detecting. 2. The group of sounding means is a group of whistle devices that generate a detection sound by a gas flow, and the detection means includes a microphone that collects the detection sounds from the group of whistle devices and outputs the sound as an electric signal. A leak detection system for a gas pipe, which comprises a pipe area having a gas leak based on an electric signal from the microphone and continuously detects the gas leak.