JP6447827B2 - Flow measuring device - Google Patents

Description

  The present invention relates to a technique for discriminating an instrument that uses a fluid by detecting a change in the flow rate of the fluid.

  There is a gas meter device that detects a change in the flow rate of a fluid in a fluid piping system and discriminates an instrument that uses the fluid (for example, Patent Document 1). There are various types of gas appliances, such as fan heaters, gas tables, water heaters, floor heating, etc., but the characteristics of the gas flow rate change at the time of ignition etc. are different, so it is in use by grasping the characteristics of the flow rate change The gas appliance can be identified.

JP 2011-95200 A

  When the gas appliance is used, the manner in which the flow rate changes even with the same appliance varies depending on the manual operation and the ignition state at that time, but it is desirable that the appliance can be accurately identified even in such a case. In the device disclosed in Patent Document 1, for example, by acquiring a flow rate indicating characteristics during the operation of the appliance from a stable flow rate or an intermediate stable flow rate, it is possible to absorb variations due to manual operation or the ignition state when using the appliance, and to determine the appliance discrimination accuracy. We are trying to improve. In the discrimination of such gas appliances, further improvement in accuracy is required.

  It is an object of the present invention to perform instrument discrimination with high accuracy even when the fluctuation of the fluid flow rate is large.

  An exemplary flow rate measuring apparatus according to the present specification includes a flow rate measuring unit that measures a flow rate of a fluid flowing through a flow path at a constant time interval, and a flow rate variation detecting unit that detects a variation in the flow rate measured by the flow rate measuring unit. Appliance feature extraction means for extracting a plurality of appliance feature flow rates indicating the characteristics of the appliance from the flow rate measured by the flow rate measurement means, and holding a plurality of characteristic flow states of specific appliances as appliance specific feature flow rates. The device-specific feature information holding unit, the plurality of device feature flow rates extracted by the device feature extraction unit, and the plurality of device-specific feature flow rates unique to the device held in the device-specific feature information holding unit. Appliance discriminating means for discriminating the specific appliance, wherein the flow rate variation detecting means has a flow rate measured by the flow rate measuring means within a first predetermined period. In the first predetermined period as the first characteristic flow of the instrument characteristic flow, and the instrument characteristic extraction means obtains the first characteristic flow obtained by the flow fluctuation detection means. , And when the flow rate measured by the flow rate measurement means continues for the second predetermined number of times within the second predetermined range, the average value of the flow rate is stored as the second characteristic flow rate of the instrument characteristic flow rate. .

  According to the flow rate measuring device of the present invention, it is possible to accurately determine the instrument even when the fluctuation of the flow rate of the fluid is large.

It is a block diagram of the flow measuring device in an embodiment of the invention. It is a schematic block diagram of the flow volume measurement means in embodiment of this invention. It is a figure which shows the flow rate change at the time of gas appliance use in embodiment of this invention, and the degree of dispersion | variation. It is a figure which shows the flow volume characteristic at the time of gas appliance use in embodiment of this invention. It is a figure which shows the flow rate change at the time of gas appliance use in embodiment of this invention, and the degree of dispersion | variation. It is a figure which shows the flow volume characteristic at the time of gas appliance use in embodiment of this invention. It is a figure which shows the flow volume measuring apparatus in embodiment of this invention.

  First, the inventions made by the present inventors are as follows.

  A flow rate measuring device according to a first invention of the present application includes a flow rate measuring unit that measures a flow rate of a fluid flowing in a flow path at a constant time interval, and a flow rate variation detecting unit that detects a variation in the flow rate measured by the flow rate measuring unit. , An appliance feature extraction means for extracting a plurality of appliance feature flow rates indicating the characteristics of the appliance from the flow rate measured by the flow measurement means, and an appliance that holds a plurality of characteristic flow states of a specific appliance as appliance-specific feature flow rates The specific feature information holding means, the plurality of appliance feature flow rates extracted by the appliance feature extraction means, and the plurality of appliance unique feature flows held by the appliance unique feature information holding means are compared, An apparatus discriminating unit for discriminating, and the flow rate variation detecting unit is configured to detect a first flow rate when the flow rate measured by the flow rate measuring unit has a predetermined variation or more within a first predetermined period. An average flow value for a predetermined period is obtained as a first feature flow of the appliance feature flow, the appliance feature extraction means holds the first feature flow obtained by the flow variation detection means, and the flow rate measured by the flow measurement means is the first feature flow. 2 When the second predetermined number of times is continued at a flow rate within a predetermined range, the average value of the flow rate for that number of times is stored as the second characteristic flow rate of the instrument characteristic flow rate.

  In the flow rate measuring device according to the second invention of the present application, the instrument feature extracting unit is configured so that the flow rate measured by the flow rate measuring unit does not continue for the first predetermined number of times within the first predetermined range and is predetermined within the first predetermined period. When it has the above dispersion | variation, the average flow value of a 1st predetermined period is preserve | saved as a 1st characteristic flow of an instrument characteristic flow.

  In the flow rate measuring device according to the third invention of the present application, the instrument feature extracting unit is configured such that, when the flow rate measured by the flow rate measuring unit continues for the first predetermined number of times within the first predetermined range, the average of the flow rate for that number of times. The value is stored as the first feature flow of the instrument feature flow.

  In the flow rate measuring device according to the fourth invention of the present application, the flow rate variation detecting means includes a flow rate measured at a specific time out of the flow rates measured by the flow rate measuring means at regular time intervals, and one before the specific time. The variation is detected using the flow rate measured at the time and the flow rate measured two times before the specific time.

  Hereinafter, a flow rate measuring device according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the embodiment described below, a gas meter is given as an example of the flow rate measuring device, and the process will be described. In the drawings, the same components are denoted by the same reference numerals, and the description of the components already described is omitted. In addition, this invention is not limited by embodiment described below.

  FIG. 1 is a block diagram of a gas meter 100 according to an embodiment of the present invention. The gas meter 100 includes a gas flow path 102, a flow rate measuring unit 104, a flow rate variation detecting unit 106, an appliance feature extracting unit 214, an appliance discriminating unit 116, and an appliance specific feature information holding unit 218. Further, the gas meter 100 includes a blocking means 122 that is disposed in the gas flow path 102 and blocks gas in an emergency or the like.

  The gas meter 100 is connected to the gas pipeline 19 on the upstream side, and connected to various gas appliances 13, 14, 15 such as a gas table, a fan heater, and floor heating on the downstream side.

  The flow rate measuring means 104 is, for example, an ultrasonic flow meter. The ultrasonic flowmeter measures the flow rate by emitting ultrasonic waves to the gas as the fluid flowing in the flow channel 102 at regular time intervals. FIG. 2 is a schematic configuration diagram of the flow rate measuring means 104. The flow rate measuring means 104 has a measurement flow path 30 having a rectangular cross section communicating with the gas flow path 102. A pair of ultrasonic transmitters / receivers 31 and 32 are disposed on the upstream side and the downstream side of the opposing channel walls of the measurement channel 30. These ultrasonic transmitters / receivers 31 and 32 are set so that the ultrasonic propagation path obliquely crosses the gas flow flowing through the measurement flow path 30, and the ultrasonic waves are alternately transmitted / received, so that the ultrasonic flow is sequentially transmitted and received. Propagation of ultrasonic waves in the opposite direction. The direction of gas flow is indicated by arrows in FIG.

  At this time, the distance between the ultrasonic transceivers 31 and 32, that is, the measurement distance is L, the angle of the ultrasonic propagation path with respect to the gas flow is φ, and the ultrasonic propagation time from the upstream to the downstream of the ultrasonic transceivers 31 and 32 is If t1, the ultrasonic propagation time from downstream to upstream is t2, and the sound velocity is C, the flow velocity V can be obtained by the following equation.

The propagation time t1 until the ultrasonic wave transmitted from the ultrasonic transmitter / receiver 31 reaches the ultrasonic transmitter / receiver 32 is expressed by the following equation.
t1 = L / (C + Vcosφ) (1)

The propagation time t2 until the ultrasonic wave transmitted from the ultrasonic transmitter / receiver 32 reaches the ultrasonic transmitter / receiver 31 is expressed by the following equation.
t2 = L / (C-Vcosφ) (2)

When the sound velocity C of the fluid is eliminated from the equations (1) and (2), the following equation is obtained.
V = (L / (2cosφ)) x ((1 / t1)-(1 / t2)) (3)

  The instantaneous flow rate of the gas flow is calculated from the flow velocity V and the cross-sectional area of the measurement channel 30. The time interval for measuring the instantaneous flow rate is arbitrary. For example, an interval of 0.5 seconds may be used, or an interval of 1 second or 2 seconds may be used.

  The flow rate variation detecting unit 106 detects a variation in flow rate measured by the flow rate measuring unit 104. The appliance feature extraction unit 214 monitors the gas flow rate measured by the flow rate measurement unit 104, and extracts a plurality of appliance feature flow rates indicating the appliance features such as a slow ignition flow rate of a fan heater from the flow rate change, If necessary, it is recorded in a memory (not shown).

  The appliance unique feature information holding unit 218 stores a plurality of appliance feature flow rates specific to the gas appliance in advance as appliance unique feature flows for each gas appliance. The appliance discriminating means 116 compares the plurality of appliance feature flow rates extracted by the appliance feature extraction means 214 with a plurality of appliance intrinsic feature flow rates unique to the appliance held in the appliance unique feature information holding means 218, and uses them as a fluid. Identify gas appliances that use gas. In addition, the appliance discriminating means 116 compares the measured gas flow rate with the appliance inherent feature flow rate stored in the appliance inherent feature information holding means 218, and discriminates the gas appliance using the gas from the similarity relationship. To do.

  The appliance feature extraction process in the flow rate measuring apparatus configured as described above will be described.

The flow rate variation detecting means 106 includes a flow rate Q (n) measured at a specific time out of the flow rates (absolute flow rate) measured by the flow rate measuring means 104 at a constant time interval (for example, 0.5 seconds), and its specification. The degree of variation using the flow rate Q (n−1) measured at the time one minute before the previous time and the flow rate Q (n−2) measured two times before the specific time Is detected. For example, the variation Va is expressed by the following equation.
Va = (Q (n) −Q (n−1)) − (Q (n−1) −Q (n−2))
= Q (n) + Q (n-2)-(Q (n-1) x 2) (4)

  In this example, the inflection point (difference twice) of the flow rate is calculated to obtain the variation Va. When the variation Va is equal to or greater than a predetermined value (for example, 35 or greater), it is determined that the flow rate variation is large.

  FIG. 3 is a diagram showing the flow rate change and the degree of variation when the gas appliance is used, and FIG. 4 is a diagram showing the flow characteristics when the gas appliance is used.

  When the gas appliance A (for example, a fan heater) corresponding to any of the gas appliances 13, 14, and 15 in FIG. 1 starts to start and a gas flow rate is generated, the measured flow rate is “flow rate value” in FIG. As shown in the graph of FIG. 4, the flow rate Q (n) = 0 to the flow rate Q (n) ≠ 0, and the flow rate changes according to the amount of gas used. Simultaneously with the measurement of the flow rate by the flow rate measuring unit 104, the flow rate variation detecting unit 106 calculates the variation Va. The calculated variation Va is shown in the “degree of variation” column of FIG.

  The instrument feature extraction unit 214 continuously performs the first predetermined number of times (for example, 3 to 5 times) within a predetermined range (for example, within a range of 40 L / h to 60 L / h). If so, the average value of the flow rate at that time is calculated and stored as an intermediate stable flow rate. In the example shown in FIG. 3 and FIG. 4, the portion where the flow rate of 40 L / h or more and 60 L / h or less continues from 3 times to 5 times applies from time 2 to time 5, and the flow rate of time 2 is 48 L / h and time. The average value 51 L / h of the flow rate 54 L / h of 3, the flow rate 50 L / h of time 4 and the flow rate 52 L / h of time 5 is stored as an intermediate stable flow rate.

  In addition, the appliance feature extraction unit 214 performs the second predetermined number of times (for example, 6 times) continuously within a predetermined range (for example, within a range of not less than 170 L / h and not more than 190 L / h) by the flow rate measuring unit 104. Then, the average value of the flow rate at that time is calculated and stored as a stable flow rate. In the example shown in FIG. 3 and FIG. 4, time 10 to time 15 apply to a portion where the flow rate of 170 L / h or more and 190 L / h or less continues six times. Average value of flow rate 184L / h at time 10, flow rate 180L / h at time 11, flow rate 184L / h at time 12, flow rate 182L / h at time 13, flow rate 180L / h at time 14, and flow rate 180L / h at time 15. 181.67 L / h is stored as a stable flow rate.

  As can be seen from the graph of FIG. 4, the stored intermediate stable flow rate corresponds to the slow ignition flow rate (between the change point I and the change point II of the graph), and the stable flow rate is the stable flow rate immediately after ignition (change point III of the graph). It can be seen that the appliance characteristic flow rate is extracted.

  Instrument-specific intermediate stable flow rate and stable flow rate, which are individual rising characteristics for each gas appliance, are stored in advance in instrument-specific feature information holding means 218, and the intermediate stable flow rate and stable flow rate of the used gas appliance are compared and determined. By doing so, it is possible to determine whether the used gas appliance is one of a plurality of registered appliances or a new appliance.

  For example, when the instrument specific feature information holding unit 218 stores information as a specific fan heater such as an intermediate stable flow rate of 50 to 60 L / h and a stable flow rate of 175 to 185 L / h in advance, the above detection result is Since it matches the content of the information, it can be determined that the appliance used is the specific fan heater.

  In the example of FIGS. 3 and 4, the flow rate measured by the flow rate measuring means 104 is a flow rate within a first predetermined range (for example, within a range of 40 L / h or more and 60 L / h or less) for a first predetermined number of times (for example, 3 times or more). Since there were continuous portions (5 times or less), the average value of the flow rate for that number of times could be stored as an intermediate stable flow rate of the instrument characteristic flow rate. For this reason, in the example of FIGS. 3 and 4, the intermediate stable flow rate can be stably acquired without using the variation Va.

  Next, a method for discriminating the gas appliance when the intermediate stable flow rate cannot be obtained stably will be described. Depending on the usage status of the gas appliance, it may be possible that an intermediate stable flow rate cannot be obtained due to fluctuations in the flow rate. Even in such a case, it is desirable that the gas appliance can be accurately identified. In the present embodiment, when the intermediate stable flow rate cannot be acquired due to the fluctuation of the flow rate, the intermediate stable flow rate is specified using the variation Va.

  FIG. 5 is a diagram showing the flow rate change and the degree of variation when using the gas appliance, and FIG. 6 is a diagram showing the flow rate characteristic when using the gas appliance.

  When the gas appliance A (for example, a fan heater) corresponding to any of the gas appliances 13, 14, and 15 in FIG. 1 starts to start and a gas flow rate is generated, the measured flow rate is “flow rate value” in FIG. As shown in the graph of FIG. 6, the flow rate Q (n) = 0 to the flow rate Q (n) ≠ 0, and the flow rate changes according to the amount of gas used. Simultaneously with the measurement of the flow rate by the flow rate measuring unit 104, the flow rate variation detecting unit 106 calculates the variation Va. The calculated variation Va is shown in the “degree of variation” column of FIG.

  The instrument feature extraction unit 214 continuously performs the first predetermined number of times (for example, 3 to 5 times) within a predetermined range (for example, within a range of 40 L / h to 60 L / h). If so, the average value of the flow rate at that time is calculated and stored as an intermediate stable flow rate. However, in the examples shown in FIG. 5 and FIG. 6, the fluctuation of the flow rate is large, and there is no portion where the flow rate is not less than 3 times and not more than 5 times within the range of 40 L / h to 60 L / h, and the intermediate stable flow rate cannot be obtained. . In this case, the flow rate variation detecting means 106 identifies a portion where the variation Va within a predetermined period (time interval is 3 or more and 5 or less) and within a predetermined period (for example, 35 or more) exists, and calculates an average flow rate value for the predetermined period. Calculated as the intermediate stable flow rate of the instrument characteristic flow rate. In the example shown in FIGS. 5 and 6, the time 3 to the time 6 apply, the flow rate 48L / h for the time 3, the flow rate 68L / h for the time 4, the flow rate 40L / h for the time 5, and the flow rate 66L / h for the time 6. The average value of 55.5 L / h is obtained as an intermediate stable flow rate. The appliance feature extraction unit 214 stores the intermediate stable flow rate obtained by the flow rate variation detection unit 106.

  In addition, the appliance feature extraction unit 214 performs the second predetermined number of times (for example, 6 times) continuously within a predetermined range (for example, within a range of not less than 170 L / h and not more than 190 L / h) by the flow rate measuring unit 104. Then, the average value of the flow rate at that time is calculated and stored as a stable flow rate. In the example shown in FIG. 5 and FIG. 6, time 10 to time 15 apply to a portion where the flow rate of 170 L / h or more and 190 L / h or less continues six times. Average value of flow rate 186L / h at time 10, flow rate 180L / h at time 11, flow rate 184L / h at time 12, flow rate 178L / h at time 13, flow rate 184L / h at time 14, and flow rate 180L / h at time 15. Store 182 L / h as a stable flow rate.

  If the instrument specific feature information holding means 218 stores information on the intermediate stable flow rate of 50 to 60 L / h and the stable flow rate of 175 to 185 L / h in advance as a specific fan heater, the above detection result is obtained from this information. Since it matches the contents, it can be determined that the appliance used is the specific fan heater.

  As described above, in the present embodiment, it is possible to specify the flow rate indicating the feature during the operation of the instrument and the flow rate indicating the characteristic at the time of stable operation even when the fluctuation of the flow rate is large, and it is possible to accurately discriminate the instrument. It becomes.

  FIG. 7 is a diagram illustrating a hardware configuration example of the gas meter 100. The gas meter 100 includes a central processing circuit (CPU) 210, a memory 220, a flow rate measuring unit 104, and a blocking unit 122.

  The CPU 210 executes a computer program 230 stored in the memory 220. The computer program 230 describes the various processes described above. The CPU 210 executes various processes of the flow rate variation detection means 106, the appliance feature extraction means 214, and the appliance discrimination means 116 shown in FIG. The memory 220 is controlled by the CPU 210 and operates as the appliance unique feature information holding unit 218. In this way, the various processes described above are executed using the CPU 210 and the memory 220, and the appliance can be discriminated with high accuracy.

  The embodiment of the present invention has been described above. The above description of the embodiment is an exemplification of the present invention and does not limit the present invention. In addition, an embodiment in which the components described in the above-described embodiments are appropriately combined is also possible. The present invention can be modified, replaced, added and omitted within the scope of the claims and the equivalents thereof.

  The present invention is particularly useful in the technical field of discriminating an instrument that uses a fluid.

13, 14, 15 Gas appliance 19 Gas pipe line 100 Gas meter 102 Gas flow path 104 Flow rate measuring means 106 Flow rate variation detecting means 116 Appliance discriminating means 122 Blocking means 214 Appliance feature extracting means 218 Appliance specific feature information holding means

Claims (4)

A flow rate measuring means for measuring the flow rate of the fluid flowing in the flow path at regular time intervals;
Flow rate variation detecting means for detecting variations in flow rate measured by the flow rate measuring unit;
Appliance feature extraction means for extracting a plurality of appliance feature flow rates indicating the characteristics of the appliance from the flow rate measured by the flow measurement means;
Device-specific feature information holding means for holding a plurality of characteristic flow states of a specific device as device-specific feature flows;
A device that discriminates the specific device by comparing the plurality of device feature flow rates extracted by the device feature extraction unit with a plurality of device unique feature flow rates unique to the device held in the device unique feature information holding unit. Discrimination means;
With
When the flow rate measured by the flow rate measuring unit has a variation greater than or equal to a predetermined value within a first predetermined period, the flow rate variation detecting unit calculates an average flow value of the first predetermined period as a first of the instrument characteristic flow rate. Obtained as a characteristic flow rate,
The appliance feature extraction unit holds the first characteristic flow rate obtained by the flow rate variation detection unit, and when the flow rate measured by the flow rate measurement unit continues for a second predetermined number of times within a second predetermined range of flow rate, A flow rate measuring device that stores an average value of the flow rate for the number of times as a second characteristic flow rate of the instrument characteristic flow rate.   When the flow rate measured by the flow rate measuring unit does not continue for a first predetermined number of times at a flow rate in a first predetermined range and has a variation of a predetermined value or more within the first predetermined period, The flow rate measuring device according to claim 1, wherein the average flow rate value of the first predetermined period is stored as the first characteristic flow rate of the instrument characteristic flow rate.   When the flow rate measured by the flow rate measuring unit continues for the first predetermined number of times within the first predetermined range, the appliance feature extracting unit calculates an average value of the flow rate for the number of times as the first of the instrument characteristic flow rate. The flow rate measuring device according to claim 2, wherein the flow rate measuring device is stored as a characteristic flow rate.   The flow rate variation detecting means includes a flow rate measured at a specific time among flow rates measured by the flow rate measuring means at regular time intervals, a flow rate measured at a time one time before the specific time, and The flow rate measuring device according to any one of claims 1 to 3, wherein the variation is detected using a flow rate measured two times before a specific time.

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