A normally closed gas meter and method of use

Abstract

The application discloses a normally closed gas meter and a use method, which comprise a normally closed detection module and a leakage detection module. The normally closed detection module is connected with a gas meter body and a gas meter valve and is used for judging and controlling whether the gas meter valve is closed. The gas leakage detection module is connected with the gas meter body, the gas meter valve and a gas pipeline pressure gauge and is used for judging whether gas leakage exists. The application fundamentally changes the working mode of a traditional gas meter and a rear pipeline which is always connected with a gas source. The gas meter is in a valve closed state during a non-gas using period, gas leakage is avoided, safety is improved, the working load of the gas meter and related equipment is reduced, and the service life is prolonged. The gas meter automatically detects gas leakage in real time, the false report rate is extremely low, no additional equipment needs to be installed, and no professional personnel needs to enter a house for detection. Gas leakage signs can be found to immediately start corresponding emergency measures, gas leakage risks are reduced, and user life and property safety are ensured.

Description

Technical Field

[0001] This invention relates to the field of gas metering technology, specifically to a normally closed gas meter and its usage method. Background Technology

[0002] Traditional gas meters keep the valve open when gas is not in use, maintaining pressure in the gas pipeline. This accelerates aging, increases malfunctions and maintenance costs, and if the pipeline ruptures due to aging or external forces such as animal bites, it can cause gas leaks, exacerbate the greenhouse effect, and have a negative impact on the environment. In severe cases, it can even lead to fires and explosions.

[0003] Currently, the main methods for preventing gas leaks are as follows: First, using automatic gas shut-off valves. However, this method has many drawbacks. Firstly, it requires additional installation, increasing user costs and maintenance. Secondly, the valve may accidentally close due to pipeline pressure fluctuations, affecting normal gas supply. Thirdly, it needs to be manually reopened, which is inconvenient for vulnerable groups such as the elderly and children. Some older gas appliances may also be incompatible, preventing proper installation of the valve. Fourthly, using gas leak detectors. However, this method also has several disadvantages. Firstly, it increases costs. Secondly, it can produce false alarms due to oil fumes, causing panic among users. Thirdly, the detectors rely on electricity and cannot function properly during power outages or when batteries are depleted. Finally, the detection range of the detectors is limited. Fifthly, regularly inspecting gas appliances and pipelines. However, this generally requires professional personnel using specialized instruments for on-site inspection, which is time-consuming, labor-intensive, and cannot be done frequently.

[0004] In view of the above-mentioned defects, the inventors of this invention have finally obtained this invention after a long period of research and practice. Summary of the Invention

[0005] To address the aforementioned technical deficiencies, the present invention provides a normally closed gas meter, comprising a normally closed detection module, a leak detection module, a gas meter valve, a gas meter body, and a gas pipeline pressure gauge. The gas meter body is used to detect the gas flow rate in the gas pipeline, the gas pipeline pressure gauge is used to detect the pipeline pressure value in the gas pipeline, and the gas meter valve is used to control the opening and closing of the gas pipeline. The normally closed detection module is connected to the gas meter body and the gas meter valve, and is used to determine and control whether to close the gas meter valve. The gas leak detection module is connected to the gas meter body, the gas meter valve, and the gas pipeline pressure gauge, and is used to determine whether a gas leak exists.

[0006] Preferably, a method of using the normally closed gas meter includes: the normally closed detection module is provided with a preset closing condition; if the preset closing condition is met, the normally closed detection module closes the gas meter valve; the preset closing condition includes a first closing condition and a second closing condition; if the first closing condition and the second closing condition are met simultaneously, the normally closed detection module closes the gas meter valve; if the first closing condition and the second closing condition are not met simultaneously, the normally closed detection module restarts the judgment process.

[0007] Preferably, the first shut-off condition is met when the current time of the gas meter body is outside the user's gas usage time period; the normally closed detection module is set with a preset timing flow rate and a preset valve closing duration. When the real-time measured flow rate of the gas meter body is less than the preset timing flow rate, valve closing timing begins. When the duration of the valve closing timing is greater than the preset valve closing duration, the second shut-off condition is met.

[0008] Preferably, the method of using the normally closed gas meter further includes: the leak detection module is equipped with a first leak detection mode and a second leak detection mode, and the first leak detection mode and the second leak detection mode perform leak detection simultaneously.

[0009] Preferably, in the first leak detection mode, the leak detection module is set with a preset leak detection duration and a preset zero-flow time period. The leak detection module monitors the real-time measured flow of the gas meter body in real time. When the real-time measured flow reaches zero, zero-flow timing begins. During the zero-flow timing process, if the real-time measured flow is greater than zero, the zero-flow timing duration is reset to zero, and continues when zero flow reappears. If no zero-flow timing exceeding the preset leak detection duration occurs within the preset zero-flow time period, a leak is determined to exist.

[0010] Preferably, in the second leak detection mode, the leak detection module sets a preset self-test time, a preset leak detection condition, and a preset judgment time period. The leak detection module determines whether the gas meter body has reached the preset self-test time. If it has, it reads the valve status of the gas meter valve. When the read valve status is open, a leak self-test is performed when the preset leak detection condition is met.

[0011] When the valve is closed, if the gas meter valve is in an openable condition, the gas meter valve will open and the pipeline pressure value will be read every ten seconds as the judgment pressure value. If two consecutive judgment pressure values ​​are equal within the preset judgment time period, or if the opening time of the gas meter valve exceeds the preset judgment time period, a leak self-check will be performed. If the gas meter valve is in an unopenable condition, a leak self-check will be performed directly.

[0012] Preferably, the leak detection preset conditions include a first leak detection condition and a second leak detection condition. A leak self-check is performed when either the first or second leak detection condition is met. A preset valve-closing time period is set. If the gas meter valve is closed during the preset valve-closing time period, the first leak detection condition is met. A preset flow rate time period and a preset flow rate duration are set. If the real-time measured flow rate reaches zero during the preset flow rate time period, a no-flow timer is started. If the real-time measured flow rate is greater than zero during the no-flow timer, the no-flow timer duration is reset to zero and resumes when zero flow occurs again. If the no-flow timer duration is greater than the preset flow rate duration, the second leak detection condition is met.

[0013] Preferably, the leakage self-test is judged as a leak if the pre-leakage condition is met. The leakage self-test is set with a preset self-test time period and a preset pressure change. The preset leakage condition is that when the gas meter valve is closed, the pipeline pressure value is read every ten seconds as the self-test pressure value. During the preset self-test time period, the difference between the maximum and minimum values ​​of the self-test pressure value is greater than the preset pressure change.

[0014] Compared with existing technologies, the advantages of this invention are as follows: This invention fundamentally changes the traditional working mode of gas meters and downstream pipelines always being connected to the gas source. During non-gas usage periods, the gas meter keeps the valve closed, preventing gas leaks, improving safety, reducing the workload of the gas meter and related equipment, and extending their service life. The gas meter automatically detects leaks in real time, with an extremely low false alarm rate and no need for additional equipment installation or professional on-site inspection. If any signs of leaks are detected, corresponding emergency measures are immediately activated, reducing user costs while also greatly reducing the risk of gas leaks caused by equipment aging or animal damage to pipelines, ensuring the safety of users' lives and property. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the normally closed gas meter.

[0016] Figure 2 This is a schematic diagram of the judgment process of the normally closed detection module;

[0017] Figure 3 This is a schematic diagram of the judgment process of the leakage detection module. Detailed Implementation

[0018] The above-mentioned and other technical features and advantages of the present invention will be described in more detail below with reference to the accompanying drawings.

[0019] like Figure 1 As shown, Figure 1 This is a schematic diagram of the normally closed gas meter.

[0020] The normally closed gas meter of this invention includes a normally closed detection module, a leak detection module, a gas meter valve, a gas meter body, and a gas pipeline pressure gauge. The gas meter body is used to detect the gas flow rate in the gas pipeline, the gas pipeline pressure gauge is used to detect the pipeline pressure value in the gas pipeline, and the gas meter valve is used to control the opening and closing of the gas pipeline. The normally closed detection module is connected to the gas meter body and the gas meter valve and is used to determine and control whether to close the gas meter valve. The gas leak detection module is connected to the gas meter body, the gas meter valve, and the gas pipeline pressure gauge and is used to determine whether a gas leak exists.

[0021] like Figure 2 and Figure 3 As shown, Figure 2 This is a schematic diagram of the judgment process of the normally closed detection module; Figure 3 This is a schematic diagram of the judgment process of the leakage detection module.

[0022] The method of using the normally closed gas meter of the present invention includes: the normally closed detection module is set with a preset closing condition; if the preset closing condition is met, the normally closed detection module closes the gas meter valve; the preset closing condition includes a first closing condition and a second closing condition; if the first closing condition and the second closing condition are met simultaneously, the normally closed detection module closes the gas meter valve; if the first closing condition and the second closing condition are not met simultaneously, the normally closed detection module restarts the judgment.

[0023] Specifically, the first shut-off condition is met when the current time of the gas meter body is outside the user's gas usage time period. Generally, the user's gas usage time period is set to 6:00 to 22:00 every day.

[0024] The normally closed detection module is set with a preset timing flow rate and a preset valve closing duration. Generally, the preset timing flow rate is 40 L / h, and the preset valve closing duration is 60 minutes. When the real-time measured flow rate of the gas meter body is less than the preset timing flow rate, valve closing timing begins. When the valve closing timing duration is greater than the preset valve closing duration, the second closing condition is met.

[0025] The method of using the normally closed gas meter of the present invention further includes: the leak detection module is provided with a first leak detection mode and a second leak detection mode, and the first leak detection mode and the second leak detection mode perform leak detection simultaneously.

[0026] The first leak detection mode includes: the leak detection module sets a preset leak detection duration and a preset zero-flow time period; the leak detection module monitors the real-time measured flow rate of the gas meter body; when the real-time measured flow rate reaches zero, zero-flow timing begins; if the real-time measured flow rate exceeds zero during the zero-flow timing process, the zero-flow timing duration is reset to zero and resumes when zero flow rate reappears; if no zero-flow timing exceeding the preset leak detection duration occurs within the preset zero-flow time period, a leak is determined to exist. Generally, the preset zero-flow time period is 24 hours, and the preset leak detection duration is 10 minutes.

[0027] The second leak detection mode includes: the leak detection module sets a preset self-test time, preset leak detection conditions, and a preset judgment time period; the leak detection module determines whether the gas meter body has reached the preset self-test time; if it has, it reads the valve status of the gas meter valve; if the read valve status is open, a leak self-test is performed when one of the preset leak detection conditions is met. The preset self-test time is generally set to 2 AM every day.

[0028] When the valve is closed, if there are no other abnormalities in the gas meter body, the gas meter valve will open, and the pipeline pressure value will be read every ten seconds as a judgment pressure value. If two consecutive judgment pressure values ​​are equal within the preset judgment time period, or if the opening time of the gas meter valve exceeds the preset judgment time period, a leak self-check will be performed. If there are other abnormalities in the gas meter body, a leak self-check will be performed directly. The preset judgment time period is 1 minute.

[0029] Specifically, the leak detection preset conditions include a first leak detection condition and a second leak detection condition.

[0030] A preset valve-closing time period is set, which is 120 minutes; if the gas meter valve is closed within the preset valve-closing time period, the first leak detection condition is met.

[0031] A preset flow time period and a preset flow duration are set, wherein the preset flow time period is 120 minutes and the preset flow duration is 30 minutes. Within the preset flow time period, if the real-time measured flow reaches zero, a no-flow timer begins. If, during the no-flow timer, the real-time measured flow exceeds zero, the no-flow timer duration is reset to zero and resumes when zero flow reappears. If the no-flow timer duration exceeds the preset flow duration, the second leak detection condition is met.

[0032] The self-check for leakage is determined to be a leak if it meets the pre-leakage conditions. The self-check for leakage is set with a preset self-check time period and a preset pressure change. The preset self-check time period is 10 minutes, and the preset pressure change is 200 Pa. The preset leakage condition is that, with the gas meter valve closed, the pipeline pressure value is read every ten seconds as the self-check pressure value. Within the preset self-check time period, the difference between the maximum and minimum self-check pressure values ​​is greater than the preset pressure change.

[0033] This invention fundamentally changes the traditional working mode of gas meters and downstream pipelines always being connected to the gas source. During non-gas usage periods, the gas meter keeps the valve closed, preventing gas leaks, improving safety, reducing the workload of the gas meter and related equipment, and extending their service life. The gas meter automatically detects leaks in real time, with an extremely low false alarm rate and no need for additional equipment installation or professional on-site inspection. Upon detecting any signs of a leak, it immediately activates corresponding emergency measures, reducing user costs while also significantly reducing the risk of gas leaks caused by equipment aging or animal damage to pipelines, ensuring the safety of users' lives and property.

[0034] Example

[0035] In a specific embodiment, the normally closed detection module is used to determine whether to close the gas meter valve. Keeping the valve closed isolates the gas meter and downstream pipeline from the gas source, preventing gas leakage and reducing the risk of fire and explosion. Every minute, the gas meter checks whether the current time on the meter is outside the preset gas usage period, which is from 6:00 AM to 10:00 PM. If it is outside the usage period, the current flow rate is obtained. If the current flow rate is less than the preset timing flow rate, timing begins. If the timing duration exceeds the preset valve closing duration, the valve is closed. The preset timing flow rate is 40 L / h, and the preset valve closing duration is 60 minutes.

[0036] The leak detection module is used to determine whether there is a gas leak. If a gas leak is detected, corresponding emergency measures will be activated immediately to ensure the safety of users' lives and property. Emergency measures include, but are not limited to, closing the gas meter valve, displaying an error code on the gas meter's LCD screen, and uploading data to the backend system.

[0037] In the first leak detection mode, the gas meter monitors the flow rate in real time. When the flow rate is zero, the timer starts; when the flow rate is greater than zero, the timer is cleared. If no timer exceeds the preset leak detection time within the preset zero flow period, a leak is determined to exist. The preset zero flow period is 24 hours, and the preset leak detection time is 10 minutes.

[0038] In the second leak detection mode, the gas meter determines whether the preset self-test time has been reached at each hour. The preset self-test time is 2 o'clock. If the preset self-test time has been reached, the gas meter valve status is read. If the read valve status is open, a leak self-test is performed when one of the following preset leak detection conditions is met.

[0039] The leak detection preset condition includes that the gas meter valve is closed during the preset valve closing time period, which is 120 minutes.

[0040] The leak detection preset conditions also include starting the timer when zero flow occurs within the preset flow time period, clearing the timer when the flow is greater than zero, and the timer duration being longer than the preset flow duration. The preset flow time period is 120 minutes and the preset flow duration is 30 minutes.

[0041] If the valve status is read as closed, and if there is no abnormal situation requiring the valve to be closed, the gas meter will automatically open the valve and read the pipeline pressure value every ten seconds. If two consecutive pressure values ​​are equal or exceed the preset judgment time period, a leak self-check will be performed. The preset judgment time period is 1 minute.

[0042] If the gas meter exhibits an abnormal condition requiring valve closure, a leak self-check will be performed directly. If the leak self-check meets the pre-leakage setting conditions, a leak is identified. These pre-leakage setting conditions are: closing the gas meter valve, reading the pipeline pressure value every ten seconds, and within the preset self-check time period, the difference between the maximum and minimum pressure values ​​exceeds the preset pressure change amount. The preset self-check time period is 10 minutes, and the preset pressure change amount is 200 Pa.

[0043] The above description is merely a preferred embodiment of the present invention and is illustrative rather than restrictive. Those skilled in the art will understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, all of which will fall within the protection scope of the present invention.

Claims

1. A normally closed gas meter, characterized in that, The system includes a normally closed detection module, a leak detection module, a gas meter valve, a gas meter body, and a gas pipeline pressure gauge. The gas meter body detects the gas flow rate in the gas pipeline, the gas pipeline pressure gauge detects the pipeline pressure, and the gas meter valve controls the opening and closing of the gas pipeline. The normally closed detection module is connected to the gas meter body and the gas meter valve to determine and control whether to close the gas meter valve. The gas leak detection module is connected to the gas meter body, the gas meter valve, and the gas pipeline pressure gauge to determine whether a gas leak exists.

2. A method of using a normally closed gas meter as described in claim 1, characterized in that, include: The normally closed detection module is equipped with a preset closing condition. If the preset closing condition is met, the normally closed detection module closes the gas meter valve. The preset closing condition includes a first closing condition and a second closing condition. If both the first closing condition and the second closing condition are met simultaneously, the normally closed detection module closes the gas meter valve. If neither the first closing condition nor the second closing condition is met simultaneously, the normally closed detection module restarts the judgment process.

3. The method of use as described in claim 2, characterized in that, When the current time of the gas meter body is outside the user's gas usage time period, the first shut-off condition is met; the normally closed detection module is set with a preset timing flow rate and a preset valve closing duration. When the real-time measured flow rate of the gas meter body is less than the preset timing flow rate, valve closing timing begins. When the valve closing timing duration is greater than the preset valve closing duration, the second shut-off condition is met.

4. The method of use as described in claim 2, characterized in that, The method of using the normally closed gas meter further includes: the leak detection module is equipped with a first leak detection mode and a second leak detection mode, and the first leak detection mode and the second leak detection mode perform leak detection simultaneously.

5. The method of use as described in claim 4, characterized in that, In the first leak detection mode, the leak detection module is set with a preset leak detection duration and a preset zero flow period. The leak detection module monitors the real-time measured flow of the gas meter body in real time. When the real-time measured flow reaches zero flow, the zero flow timer starts. During the zero-flow timing process, if the real-time measured flow rate is greater than the zero flow rate, the zero-flow timing duration is reset to zero and continues when the zero flow rate reappears; if no zero-flow timing exceeding the preset leak detection duration occurs within the preset zero-flow time period, it is determined that a leak exists.

6. The method of use as described in claim 4, characterized in that, In the second leak detection mode, the leak detection module sets a preset self-test time, a preset leak detection condition, and a preset judgment time period. The leak detection module determines whether the gas meter body has reached the preset self-test time. If it has, it reads the valve status of the gas meter valve. When the read valve status is open, a leak self-test is performed when the preset leak detection condition is met. When the valve is closed, if the gas meter valve is in an openable condition, the gas meter valve will open and the pipeline pressure value will be read every ten seconds as the judgment pressure value. If two consecutive judgment pressure values ​​are equal within the preset judgment time period, or if the opening time of the gas meter valve exceeds the preset judgment time period, a leak self-check will be performed. If the gas meter valve is in an unopenable condition, a leak self-check will be performed directly.

7. The method of use as described in claim 6, characterized in that, The leak detection preset conditions include a first leak detection condition and a second leak detection condition. A leak self-test is performed when either the first or second leak detection condition is met. A preset valve closing time period is set. During the preset valve closing time period, the gas meter valve is in a closed state, which satisfies the first leak detection condition. Set a preset flow time period and a preset flow duration. If the real-time measured flow reaches zero flow within the preset flow time period, start the no-flow timing. During the no-flow timing process, if the real-time measured flow is greater than zero flow, the duration of the no-flow timing is reset to zero, and it continues when zero flow reappears; if the duration of the no-flow timing is greater than the preset flow duration, the second leak detection condition is met.

8. The method of use as described in claim 6, characterized in that, If the self-test for leakage meets the pre-leakage setting conditions, it is judged as a leak. The self-test for leakage is set with a preset self-test time period and a preset pressure change. The preset leakage condition is that when the gas meter valve is closed, the pipeline pressure value is read every ten seconds as the self-test pressure value. Within the preset self-test time period, the difference between the maximum and minimum values ​​of the self-test pressure value is greater than the preset pressure change.

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