Gas flow measurement device

Abstract

To provide a gas flow measurement device capable of further improving the accuracy of gas flow measurement.SOLUTION: A gas flow measurement device 1 includes: a measuring unit 22 for measuring the instantaneous flow rate Q of the gas; a control unit 20 that controls the operation of the measuring unit 22; and a storage unit 21. The control unit 20 executes: a series of flow measurement processing (S3) to cause the measuring unit 22 to measure of instantaneous gas flow rate Q for every first period T1; a series of deviation calculation processing (S5) of collecting measured instantaneous gas flow rate Q as many as the number of times corresponding to a second period T2 and calculating standard deviation σ regarding the collected multiple instantaneous flow rates Q; and a series of determination processing (S9) of determining whether the calculated standard deviation σ is greater than or equal to a threshold σt stored in storage unit 21.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a gas flow measurement device for measuring the flow rate of gas in a pipe to which gas is supplied.

Background Art

[0002] Conventionally, for example, fuel gas has been supplied to gas-consuming households such as individual households through pipes. And, in order to perform billing or provide discount services according to the amount of gas used in each household, a gas flow measurement device is attached to the pipe so that the amount of gas used (consumption) for each household can be measured. As such a gas flow measurement device, for example, devices such as ultrasonic type and thermal type are known as those capable of accurately measuring the instantaneous flow rate of gas.

[0003] By the way, Patent Document 1 proposes a flow measurement device aimed at further improving the measurement accuracy of the gas flow rate. Specifically, in Patent Document 1, paying attention to the fact that pulsation (that is, gas pressure fluctuation) occurring in the pipe through which gas flows induces a measurement error, a method for eliminating the measurement error caused by this pulsation is proposed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the phenomenon that causes an error in gas flow measurement is not only pulsation.

[0006] Therefore, an object of the present disclosure is to provide a gas flow measurement device capable of further improving measurement accuracy.

Means for Solving the Problems

[0007] The gas flow rate measuring device of the present disclosure includes a measuring device that measures the instantaneous flow rate of a gas, a control device that controls the operation of the measuring device, and a storage device. The control device performs a flow rate measurement process of causing the measuring device to measure the instantaneous flow rate of the gas every predetermined first period, collects the instantaneous flow rates measured by the flow rate measurement process a number of times corresponding to a predetermined second period longer than the first period, and calculates a standard deviation for the plurality of collected instantaneous flow rates. The control device also performs a determination process of determining whether the standard deviation calculated by the deviation calculation process is equal to or greater than a predetermined threshold value stored in the storage device.

Advantages of the Invention

[0008] According to the gas flow rate measuring device according to the present disclosure, the gas flow rate can be measured more accurately.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0010] As described above, pulsation, which is a pressure fluctuation of gas, is one of the factors that cause errors in gas flow measurement. However, there are various factors other than pulsation that affect the measurement accuracy of the flow rate. As a result of verification by the present inventors, it has been discovered that, for example, due to unstable operation of the measurement device itself, etc., a phenomenon may occur in which the measured value of the gas fluctuates (varies) with a shorter period than in the case of pulsation. Therefore, the present inventors have invented the gas flow measurement device according to the present disclosure in order to eliminate the decrease in measurement accuracy caused by such variations in the measured value in a short period.

[0011] Hereinafter, specific embodiments of such a gas flow measurement device will be described. In each embodiment, an example in which an ultrasonic method is adopted as a method for measuring the gas flow rate is shown, but the present invention is not limited thereto. Any configuration that can measure the so-called instantaneous flow rate may be used. For example, a configuration adopting a known thermal measurement method may also be used.

[0012] The gas flow measurement device according to the present disclosure includes a measurement device that measures the instantaneous flow rate of gas, a control device that controls the operation of the measurement device, and a storage device. The control device executes a flow rate measurement process for causing the measurement device to measure the instantaneous flow rate of gas at predetermined first periods, a deviation calculation process for collecting the instantaneous flow rates measured by the flow rate measurement process a number of times corresponding to a predetermined second period longer than the first period and calculating the standard deviation for the plurality of collected instantaneous flow rates, and a determination process for determining whether or not the standard deviation calculated by the deviation calculation process is equal to or greater than a predetermined threshold value stored in the storage device.

[0013] Hereinafter, specific embodiments of such a gas flow measurement device will be described. However, the configurations other than those described above mentioned in the present embodiment are arbitrary configurations in the present disclosure and are not essential. Also, hereinafter, the same or corresponding elements will be given the same reference numerals throughout all the drawings, and duplicate descriptions will be omitted.

[0014] FIG. 1 is a schematic diagram of a gas flow rate measuring device 1 according to the present embodiment. The gas flow rate measuring device 1 is provided in the middle of a gas pipe 100 that constitutes a flow path network for supplying gas. The flow path network for supplying gas is composed of a pipe network that extends from a gas supply facility located on the upstream side to a plurality of customer houses located on the downstream side while branching appropriately in the middle. A part of this pipe network is constituted by the above gas pipe 100. Further, each customer house is equipped with gas-consuming equipment, and the gas flowing through the gas pipe 100 is consumed by this gas-consuming equipment. Examples of the gas-consuming equipment include a gas stove, a gas fan heater, a water heater, a fuel cell system, and the like.

[0015] The gas flow rate measuring device 1 includes a measurement unit 2 and a flow path unit 3. Among these, the flow path unit 3 has a flow path main body 10. The flow path main body 10 is composed of a pipe member made of metal, resin, or the like and having a circular or rectangular cross section. The flow path main body 10 is provided intervening in the middle of the gas pipe 100, and its internal space communicates with the internal space of the gas pipe 100 to form a gas flow path 13. That is, the flow path main body 10 has an upstream opening 11 and a downstream opening 12, and the gas flowing in from the upstream opening 11 flows through the flow path 13 and flows out from the downstream opening 12.

[0016] The flow path 13 of the flow path main body 10 includes a measurement area 14 for measuring the flow rate of gas. The measurement area 14 is an area of the flow path of the flow path main body 10 that includes a propagation path of ultrasonic waves described later, and is formed so that the cross-sectional area is constant over the entire region in the gas flow direction.

[0017] The flow path unit 3 has a first ultrasonic transceiver 15 and a second ultrasonic transceiver 16 provided on the flow path main body 10 and capable of transmitting and receiving ultrasonic waves. These first ultrasonic transceiver 15 and second ultrasonic transceiver 16 constitute a measuring device that measures a physical quantity having a correlation with the instantaneous flow rate of gas in the flow path 13 and outputs a signal. In the present embodiment, this physical quantity is exemplified by the propagation time of ultrasonic waves.

[0018] In the case of Fig. 1, the first ultrasonic transceiver 15 is arranged on the upstream side in the direction of gas flow in the flow path main body 10, and the second ultrasonic transceiver 16 is arranged on the downstream side of the first ultrasonic transceiver 15. Also, the first ultrasonic transceiver 15 and the second ultrasonic transceiver 16 are arranged on the wall portions in the same direction with respect to the flow center line of the flow path 13, with the ultrasonic transmission direction facing the flow path 13 side. Then, the ultrasonic wave transmitted from the first ultrasonic transceiver 15 is reflected by the inner wall surface of the flow path main body 10 and received by the second ultrasonic transceiver 16 through a V-shaped path, and the ultrasonic wave transmitted from the second ultrasonic transceiver 16 is reflected by the inner wall surface of the flow path main body 10 and received by the first ultrasonic transceiver 15 through a V-shaped path. In this way, a V-shaped ultrasonic propagation path 17 is formed between the first ultrasonic transceiver 15 and the second ultrasonic transceiver 16.

[0019] Also, in the case of such a propagation path 17, the propagation of the ultrasonic wave from the first ultrasonic transceiver 15 to the second ultrasonic transceiver 16 is in the forward direction with respect to the gas flow, and the propagation of the ultrasonic wave from the second ultrasonic transceiver 16 to the first ultrasonic transceiver 15 is in the reverse direction with respect to the gas flow. Therefore, when the gas is flowing, a difference Δt occurs between the first propagation time td required for the ultrasonic wave transmitted by the first ultrasonic transceiver 15 to be received by the second ultrasonic transceiver 16 and the second propagation time tu required for the ultrasonic wave transmitted by the second ultrasonic transceiver 16 to be received by the first ultrasonic transceiver 15. And this propagation time difference Δt changes according to the flow velocity of the gas. Thus, the flow velocity of the gas can be obtained from the propagation time difference Δt, and furthermore, the gas flow rate Q can be obtained based on the flow velocity of the gas and the cross-sectional area of the flow path 13.

[0020] Note that the propagation speed of ultrasonic waves in the gas is sufficiently fast, and the time required to calculate the flow rate Q from the propagation time difference Δt is also extremely short (for example, less than 1 second). Therefore, the gas flow rate Q obtained by the above method is referred to as the instantaneous flow rate, especially when compared with the flow rate obtained by the membrane type flow measurement method.

[0021] Incidentally, the arrangements of the first ultrasonic transmitter / receiver 15 and the second ultrasonic transmitter / receiver 16 are not limited to those shown in FIG. 1. That is, in FIG. 1, an arrangement in which the propagation path 17 forms a V shape is illustrated, but it is not limited to this. The first ultrasonic transmitter / receiver 15 and the second ultrasonic transmitter / receiver 16 may be arranged on the upstream side and the downstream side while facing each other across the flow center line, or an arrangement may be adopted such that ultrasonic waves transmitted from one are received by the other after being reflected two or more times by the inner wall surface of the flow path body 10.

[0022] The measurement unit 2 is, in terms of hardware, composed of a computer system having one or more processors, memories, and communication interfaces respectively. Also, in terms of a functional configuration, the measurement unit 2 includes a control device 20, a storage device 21, and a measurement device 22.

[0023] The control device 20 is composed of a processor, an internal memory, etc., and controls the operations of each part of the gas flow measurement device 1 according to a computer program and data stored in the storage device 21 which is an internal memory or an external memory. For example, the control device 20 functions as at least a flow rate measurement unit 30, a deviation calculation unit 31, and a determination unit 32.

[0024] Among these, the control device 20 functioning as the flow rate measurement unit 30 causes the measurement device 22 to measure the instantaneous flow rate of the gas flowing through the flow path 13. That is, the flow rate measurement unit 30 drives the measurement device 22 to measure the instantaneous flow rate Q of the gas flowing through the flow path 13 every predetermined first period T1 (for example, 2 seconds). Note that the control device 30 causes the measured instantaneous flow rate Q to be cumulatively stored in the storage device 21.

[0025] Further, the control device 20 functioning as the deviation calculation unit 31 calculates a standard deviation using a plurality of instantaneous flow rates Q measured every first period T1. That is, the deviation calculation unit 31 collects the instantaneous flow rate Q the number of times corresponding to a predetermined second period T2 (for example, 10 minutes) longer than the first period T1, and calculates the standard deviation σ for the collected plurality of instantaneous flow rates Q. When the first period T1 is 2 seconds and the second period T2 is 10 minutes as described above, the deviation calculation unit 31 reads out (collects) the instantaneous flow rate Q which is the measured value for a total of 300 times accumulated and stored in the storage device 21, and calculates the standard deviation σ using this.

[0026] Further, the control device 20 functioning as the determination unit 32 determines whether or not the standard deviation σ calculated as described above is equal to or greater than a predetermined threshold value σt stored in advance in the storage device 21.

[0027] On the other hand, the storage device 21 is composed of a volatile memory, a non-volatile memory, etc., stores a computer program and various data, and is readable and writable by the control device 20. For example, the storage device 21 stores a computer program for causing the control device 20 to function as the above-described respective units 30 to 32, etc. Further, the storage device 21 stores in advance a predetermined threshold value σt related to the standard deviation, and stores in real time the instantaneous flow rate Q measured in a timely manner after the installation of the gas flow measurement device 1 and the calculated standard deviation σ.

[0028] Further, the measurement device 22 is composed of a microcomputer made of an electronic circuit, a memory that stores a computer program, etc. The measurement device 22 operates based on a control signal from the control device 20, drives the first ultrasonic transceiver 15 and the second ultrasonic transceiver 16, and measures the instantaneous flow rate Q of the gas. That is, as described above, the first ultrasonic transceiver 15 and the second ultrasonic transceiver 16 are driven to measure the first propagation time td and the second propagation time tu, the propagation time difference Δt is calculated from these, and further, the instantaneous flow rate Q is calculated based on the cross-sectional area of the flow path 13. The measurement device 22 transmits the calculated instantaneous flow rate Q to the control device 20, and the control device 20 stores this in the storage device 21.

[0029] In this embodiment, the first ultrasonic transceiver 15 and the second ultrasonic transceiver 16, which are the pair of ultrasonic transceivers described above, are components of the flow path unit 3 and also form part of the configuration of the measuring device 22. Further, the gas flow rate measuring device 1 described above operates, for example, by power supply from a battery (not shown).

[0030] Next, the operation of the gas flow rate measuring device 1 will be described with reference to the flowchart of FIG. 2. The flowchart of FIG. 2 shows a determination operation for determining the presence or absence of an abnormality in which the measured value of the instantaneous flow rate Q varies significantly in a short period of time, among the operations of the gas flow rate measuring device 1.

[0031] As shown in FIG. 2, the gas flow rate measuring device 1 starts the flow rate measurement process (step S1). That is, the control device 20 functioning as the flow rate measurement unit 30 controls the measuring device 22 to start measuring the instantaneous flow rate Q. At the same time as the start of the flow rate measurement process, the counter C is reset to C = 1 (step S2). Then, when one measurement of the instantaneous flow rate Q is completed, the counter C is incremented by 1 (step S3). The measured instantaneous flow rate Q is stored in the storage device 21.

[0032] The measurement of the instantaneous flow rate Q and the increment of the counter C are repeated until the counter C reaches a predetermined value N (S3, S4). That is, when the counter C is less than N (S4: YES), the control device 20 repeats the operation of step S3, and when it is determined that the counter C = N (S4: NO), the process proceeds to step S5. In the case of this embodiment, the measurement period of the instantaneous flow rate Q in step S3 corresponds to the first period T1 and is, for example, 2 seconds, and the predetermined value N referred to in step S4 is, for example, 300 when the second period T2 is 10 minutes.

[0033] When the control device 20 determines in step S4 that the counter C = N, it calculates the standard deviation σ for each of the N instantaneous flow rates Q stored in the storage device 21 (step S5). Also, it calculates the average flow rate Qave using each of the N instantaneous flow rates Q for the same sample (step S6). Then, it specifies the category based on the average flow rate Qave (step S7), and the deviation calculation unit 31 acquires the threshold value σt for the standard deviation based on the specified category (step S8).

[0034] More specifically, the gas flow rate measuring device 1 determines the presence or absence of an abnormality based on the degree of variation of a plurality of instantaneous flow rates Q, which is grasped by comparing the standard deviation obtained from a predetermined number of samples regarding the instantaneous flow rate Q with a predetermined threshold value. Here, the degree of variation serving as an index for determining the abnormality of the instantaneous flow rate Q may differ depending on the volume of the instantaneous flow rate Q. Therefore, in the gas flow rate measuring device 1 according to the present embodiment, different values are used as the threshold value σt to be compared with the standard deviation σ according to the volume of the instantaneous flow rate Q.

[0035] FIG. 3 is a chart showing an example of a reference table regarding threshold values σt of different values, and such table information is stored in the storage device 21. In this example, as the volume of the instantaneous flow rate Q, the average flow rate Qave calculated from the N instantaneous flow rates Q in step S6 is used (denoted as Q in FIG. 3). As shown in FIG. 3, category 1 is the case where the average flow rate Qave is less than the flow rate q1, and the threshold value of the standard deviation at this time is set to σt1. Category 2 is the case where the average flow rate Qave is equal to or greater than the flow rate q1 and less than the flow rate q2, and the threshold value of the standard deviation at this time is set to σt2. Category 3 is the case where the average flow rate Qave is equal to or greater than the flow rate q2 and less than the flow rate q3, and the threshold value of the standard deviation at this time is set to σt3. Category 4 is the case where the average flow rate Qave is equal to or greater than the flow rate q3, and the threshold value of the standard deviation at this time is set to σt4.

[0036] Therefore, in step S7 of FIG. 2, the control device 20 specifies a category by referring to the table information in FIG. 3 based on the average flow rate Qave calculated in step S6. Further, in step S8, the control device 20 acquires a threshold value σt corresponding to the specified category.

[0037] Next, the control device 20 functioning as the determination unit 32 compares the standard deviation σ with the threshold value σt (step S9). As a result, if it is determined that the standard deviation σ is greater than the threshold value σt (S9: YES), it is determined as abnormal (step S10). If it is determined that the standard deviation σ is less than or equal to the threshold value σt (S9: NO), it is determined as normal (step S11). After determining the presence or absence of an abnormality in this way, this flow is terminated.

[0038] According to the gas flow rate measuring device 1 described above, the gas flow rate can be measured more accurately. In particular, when a variation phenomenon of the measured value occurs in a shorter cycle than general pulsation, the possibility of an operation abnormality of the gas flow rate measuring device 1 itself is also considered. In the gas flow rate measuring device 1 according to the present embodiment, it is also possible to self-diagnose an operation abnormality at such a time. Further, when the operation of the gas flow rate measuring device 1 is normal, it is possible to detect an abnormal variation phenomenon of the measured value due to an external factor.

[0039] In the above description, an example is shown in which the threshold value σt compared with the standard deviation σ in step S9 uses different values according to the average flow rate Qave, but the present invention is not limited to this. For example, when the difference in the average flow rate Qave does not significantly affect the standard deviation σ depending on the configuration of the flow path body 10 or the type of gas flowing through it, etc., a configuration may be adopted in which a single threshold value σt is compared regardless of the average flow rate Qave.

[0040] Also, in step S3, an example is shown in which the number of times of measuring the instantaneous flow rate Q is determined by the counter C, but the present invention is not limited to this. For example, the elapsed time from the start (S1) of the flow rate measurement process may be measured, and the measurement of the instantaneous flow rate Q may be periodically repeated until this reaches a predetermined time (for example, the second period T2).

[0041] (Modification 1) The gas flow rate measuring device 1 according to the present embodiment may have a configuration according to the following Modification Example 1. That is, when it is determined in step S9 of FIG. 2 that there is an abnormality (S10) as a result of the determination, the gas flow rate measuring device 1 according to Modification Example 1 deletes data on a plurality of instantaneous flow rates Q used for this determination (data collected and stored in the corresponding second period T2) from the storage device 21. Further, data on the average flow rate Qave calculated from these instantaneous flow rates Q may also be deleted from the storage device 21.

[0042] In this case, it is possible to prevent unnecessary data from being erroneously referred to and treated as the flow rate of normal gas. Further, an increase in the capacity of the memory of the storage device 21 can be suppressed.

[0043] (Modification Example 3) The gas flow rate measuring device 1 according to the present embodiment may also have a configuration according to the following Modification Example 2. FIG. 4 is a schematic diagram of the gas flow rate measuring device 1 according to Modification Example 2. As shown in FIG. 4, this gas flow rate measuring device 1 is different from the gas flow rate measuring device 1 according to the embodiment in that the control device 20 further includes a reset unit 33. Since the other configurations are the same as those described in the first embodiment, the description thereof is omitted here.

[0044] In Modification Example 2, when it is determined in step S9 of FIG. 2 that the standard deviation σ is equal to or greater than the threshold value σt (S9: YES), the control device 20 functioning as the reset unit 33 executes a reset of the electronic circuit constituting the measuring device 22. For example, the electronic circuit is restarted as a reset.

[0045] Accordingly, when the cause of the measurement value variation phenomenon lies in the abnormal operation of the measuring device 22, resetting the electronic circuit of the measuring device 22 may eliminate the cause. In this case, since data such as the measured instantaneous flow rate Q and the preset threshold value σt are stored in the storage device 21, these data will not be lost due to the reset of the measuring device 22. However, data such as the instantaneous flow rate Q and the average flow rate Qave measured during the abnormal operation of the measuring device 22 may be deleted from the storage device 21 in conjunction with the execution of the above reset. That is, Modification 1 and Modification 2 can also be applied to Embodiment 1 simultaneously.

[0046] Also, the following techniques are disclosed by the description of the above embodiments.

[0047] (Technique 1) The gas flow rate measuring device of Technique 1 includes a measuring device for measuring the instantaneous flow rate of gas, a control device for controlling the operation of the measuring device, and a storage device. The control device executes a flow rate measurement process for causing the measuring device to measure the instantaneous flow rate of gas at predetermined first periods, a deviation calculation process for collecting the instantaneous flow rates measured by the flow rate measurement process a number of times corresponding to a predetermined second period longer than the first period and calculating the standard deviation for the collected plurality of instantaneous flow rates, and a determination process for determining whether the standard deviation calculated by the deviation calculation process is equal to or greater than a predetermined threshold value stored in the storage device.

[0048] Thereby, the gas flow rate can be measured more accurately. In particular, when a measurement value variation phenomenon occurs in a shorter cycle than general pulsation, this can be determined as an abnormality.

[0049] (Technique 2) In the gas flow rate measuring device of Technique 2, in Technique 1, different values of the threshold value corresponding to the gas flow rate in the second period are stored in the storage device.

[0050] Thus, by using a judgment criterion according to the flow rate, it is possible to determine the abnormality of the measurement value variation phenomenon, and thus a more accurate determination can be made.

[0051] (Technology 3) In the gas flow rate measuring device of Technology 3, in Technology 1 or 2, the control device stores the instantaneous flow rate of the gas in the storage device, and deletes the instantaneous flow rate measured during the second period in which the standard deviation is determined to be equal to or greater than the threshold value by the determination process from the storage device.

[0052] Thus, data regarding the instantaneous flow rate when an abnormality is determined can be deleted, preventing these data from being erroneously referred to as normal data.

[0053] (Technology 4) The gas flow rate measuring device of Technology 4, in any of Technologies 1 to 3, the measuring device has a pair of ultrasonic transceivers that transmit and receive ultrasonic waves to and from each other through a flow path through which gas flows, and the control device measures the instantaneous flow rate of the gas based on the propagation time of ultrasonic waves between the pair of ultrasonic transceivers in the flow rate measurement process.

[0054] Thus, since the instantaneous flow rate can be measured in a short time of less than 1 second, it is possible to accurately detect the variation phenomenon of the measurement value in a shorter cycle than the pulsation, and to determine the presence or absence of an abnormality.

[0055] (Technology 5) The gas flow rate measuring device of Technology 5, in any of Technologies 1 to 4, when the standard deviation is determined to be equal to or greater than the threshold value by the determination process, the control device executes a reset process for resetting the electronic circuit constituting the measuring device.

[0056] Thus, when there is an abnormality in the operation of the measuring device, there is a possibility that the abnormality of the measurement operation can be eliminated by a reset process such as restarting.

Industrial Applicability

[0057] The present disclosure can be applied to a gas flow rate measuring device that measures the flow rate of a gas.

Explanation of Signs

[0058] 1 Gas flow rate measurement system 2 Gas flow rate measuring device 3 Flow path unit 10 Flow path body 13 Flow path 20 Control device 21 Storage device 22 Measuring device 100 Gas pipe

Claims

1. A measuring device for measuring the instantaneous flow rate of a gas, a control device for controlling the operation of the measuring device, and a storage device, wherein the control device performs a flow rate measurement process for causing the measuring device to measure the instantaneous flow rate of the gas every predetermined first period, collects the instantaneous flow rates measured by the flow rate measurement process a number of times corresponding to a predetermined second period longer than the first period, and performs a deviation calculation process for calculating a standard deviation for the plurality of collected instantaneous flow rates, and executes a determination process for determining whether or not the standard deviation calculated by the deviation calculation process is equal to or greater than a predetermined threshold value stored in the storage device. A gas flow rate measuring device.

2. The threshold values stored in the storage device are different values depending on the gas flow rate during the second period. The gas flow rate measuring device according to Claim 1.

3. The control device stores the instantaneous flow rate of the gas in the storage device, and deletes the instantaneous flow rate measured during the second period in which the standard deviation is determined to be equal to or greater than the threshold value by the determination process from the storage device. The gas flow rate measuring device according to Claim 1.

4. The measuring device has a pair of ultrasonic transceivers that transmit and receive ultrasonic waves to and from each other through a flow path through which the gas flows, and in the flow rate measurement process, the control device measures the instantaneous flow rate of the gas based on the propagation time of the ultrasonic waves between the pair of ultrasonic transceivers. The gas flow rate measuring device according to Claim 1.

5. When the standard deviation is determined to be equal to or greater than the threshold value by the determination process, the control device executes a reset process for resetting the electronic circuit constituting the measuring device. The gas flow rate measuring device according to Claim 1.

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