JP5182153B2 - Flow rate measuring device and fluid supply system - Google Patents

Description

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

  Conventionally, there exists a thing of patent documents 1 as a gas meter device which specifies a use instrument in a fluid piping system which has a gas meter device.

  As shown in FIG. 6, the gas meter device 100 of this document is disposed in a flow path 102 connected to a household gas supply pipe 19, and includes a flow rate measurement unit 104, a measured flow rate information storage unit 106, a calculation unit 108, The flow rate classification table holding unit 110, the difference value conversion unit 112, the code string generation unit 114, the appliance discriminating unit 116, the appliance unique code string information holding unit 118, the appliance-specific flow rate calculation unit 120, and the flow path cutoff And a valve 122.

  In the gas meter device 100, the flow rate measuring unit 104 measures the flow rate of the gas as the fluid flowing in the flow path 102 at regular time intervals. The measured flow rate information storage unit 106 stores the measured flow value measured by the flow rate measuring unit 104 and target data described in association with the measurement time when the measured flow rate value was measured.

  The calculation unit 108 calculates a difference value of the gas flow rate measured by the flow rate measurement unit 104 at regular intervals.

  The flow rate classification table holding unit 110 holds a flow rate classification table 110a in which a plurality of difference value categories according to the size of the difference values and codes representing each category are associated with each other as shown in FIG. is there. The flow rate classification table 110a functions as a conversion table that classifies the measured difference values into predetermined categories and converts them into predetermined codes representing the categories.

  The difference value conversion unit 112 converts the difference value calculated by the calculation unit 108 into a code representing a category into which the difference value for each predetermined time is classified based on the flow rate classification table 110a. The code string generation unit 114 generates a measurement code string, which is a code string obtained by actual measurement, based on a set of codes at regular intervals obtained by the difference value conversion unit 112. This measurement code string represents a change in the flow rate of the fluid in a pseudo manner. The code generation unit 114 records the generated measurement code string in a memory (not shown) as necessary.

  The appliance discriminating unit 116 discriminates various gas appliances 13, 14, and 15 using gas as a fluid based on the measurement code sequence generated by the code sequence generating unit 114. Here, the appliance discriminating unit 116 compares the measurement code sequence with an appliance specific code sequence indicating a code sequence specific to the gas appliance stored in advance in the appliance specific code sequence information holding unit 118 for each gas appliance, and the similarity relationship between them. The gas appliance that uses gas is determined from the above.

The appliance-specific flow rate calculation unit 120 calculates the flow rate for each gas appliance determined by the appliance determination unit 116.
JP 2008-309498 A

In the above configuration, since the reference value of the classification of the flow rate classification table is determined by the absolute value, in order to accurately discriminate devices having different activation flow value values, a plurality of flow rate classification tables corresponding to the activation flow value values are required. It is necessary to use this, and the required amount of memory increases by the number of flow rate classification tables.

  The present invention has been made to solve the above-described problems. The purpose of the present invention is to suppress an increase in the amount of memory necessary for calculation even when identifying instruments having different starting flow rates, and to improve the calculation speed and instrument identification accuracy. The goal is to improve.

The flow rate measuring device of the present invention includes a flow rate measuring unit that measures the flow rate of the fluid flowing in the flow path at regular time intervals, and an arithmetic unit that computes a difference value of the flow rate measured by the flow rate measuring unit at regular intervals. The flow rate measured by the flow rate measurement unit is divided into a plurality of activation flow value detection units that detect activation flow value values during instrument operation, and reference values determined according to the magnitude of the activation flow value.
The difference value group, the flow rate classification table associated with the code representing each category, the activation flow value detected by the activation flow value detection unit and the difference value calculated by the calculation unit, the flow rate A difference value conversion unit that converts the code into the code based on a classification table; a code string generation unit that generates a measurement code string based on the set of codes at regular intervals obtained by the difference value conversion unit; and the measurement code The device includes a device discriminating unit that compares the device with a device-specific code sequence indicating a device-specific code sequence for each device, and determines the device that uses the fluid.

  According to the present invention, when discriminating a device that uses a fluid, the reference value of the classification of the flow rate classification table is set to a variable value corresponding to the startup flow rate, so that the flow rate can be adjusted even for appliances having different startup flow rate values. There is no need to use a plurality of partition tables, and a sign value obtained by encoding (converting) a difference value of flow rate based on the same one is used. Therefore, when performing appliance discrimination, it is possible to suppress an increase in the amount of memory required for computation and improve the calculation speed and appliance discrimination accuracy.

  In the flow rate measuring device of the present invention, since the reference value of the classification of the flow rate classification table is determined by, for example, the ratio to the starting flow rate value, the reference value can be obtained by simple calculation, so that the calculation speed It is possible to improve the accuracy of appliance discrimination.

  Further, in the flow rate measuring device of the present invention, the reference value of the classification of the flow rate classification table is, for example, the ratio where the influence of the activation flow value is large with the activation flow value, and the part where the influence of the activation flow value is small. Since the reference value can be obtained by a simple calculation only for a necessary portion by setting the value by a combination such as a value, it is possible to improve the calculation speed and the instrument discrimination accuracy.

  Further, in the flow rate measuring device of the present invention, the appliance discriminating unit is combined with the comparison of the starting flow rate values in addition to the comparison of only the code strings, so that the discrimination is difficult only by the comparison of the code strings. Even if it exists, a more accurate discrimination | determination is attained by combining the comparison of starting flow volume value.

  Furthermore, according to the present invention, a flow rate measuring method executed by the flow rate measuring device and a computer program for controlling the flow rate measuring device are provided. Furthermore, a fluid supply system using these apparatuses, methods, and programs is provided.

  According to the present invention, when discriminating instruments having different activation flow rate values, it is possible to suppress an increase in the required memory amount and improve the calculation speed and the instrument discriminating accuracy.

The first invention includes a flow rate measurement unit that measures the flow rate of the fluid flowing through the flow path at a constant time interval, a calculation unit that calculates a difference value of the flow rate measured by the flow rate measurement unit for each predetermined time, The flow rate measured by the flow rate measurement unit, and the flow rate measured by the activation flow rate value detection unit for detecting the activation flow value during the operation of the instrument, and the difference value divided into a plurality of reference values determined according to the magnitude of the flow rate value of the activation flow rate Based on the flow rate classification table, the flow rate classification table associated with the code representing each classification, the activation flow value detected by the activation flow value detection unit and the difference value calculated by the calculation unit A difference value conversion unit for converting to the code, a code sequence generation unit for generating a measurement code sequence based on the set of codes for each predetermined time obtained by the difference value conversion unit, the measurement code sequence, and an instrument Per Code string Yu compares the instrument-specific code sequence indicating the one in which and a appliance determination unit that determines an appliance that uses a fluid.

  According to this, when discriminating the appliance that uses the fluid, by setting the reference value of the classification of the flow rate classification table to a variable value that is commensurate with the startup flow rate, the flow rate classification can be performed even for instruments having different startup flow rate values. It is not necessary to use a plurality of tables, and a code value obtained by encoding (converting) the difference value of the flow rate based on the same table is used. Therefore, when performing appliance discrimination, it is possible to suppress an increase in the amount of memory required for computation and improve the calculation speed and appliance discrimination accuracy.

  In particular, the second invention is characterized in that, in the first invention, the reference value of the classification of the flow rate classification table is determined by the ratio with the starting flow rate value.

  According to this, since the reference value can be obtained by a simple calculation, it is possible to improve the calculation speed and the instrument discrimination accuracy.

  In particular, the third invention is characterized in that, in the first invention, the reference value of the classification of the flow rate classification table is determined by a combination of a ratio with the starting flow rate value and an absolute value.

  According to this, since the reference value can be obtained by simple calculation only for a necessary portion, it is possible to improve the calculation speed and the instrument discrimination accuracy.

  In a fourth aspect of the invention, in particular, in any one of the first to third aspects of the invention, the appliance discriminating unit compares the measurement code string with an instrument specific code string indicating a specific code string for each instrument. The activation flow value detected by the activation flow value detection unit is compared with the unique activation flow value for each appliance, and the appliance using the fluid is discriminated.

  According to this, even when it is difficult to determine only by comparing the code strings, more accurate determination can be performed by combining the comparison of the startup flow rate values.

  According to a fifth aspect of the invention, in particular, in any one of the first to fourth aspects of the invention, the flow rate measurement unit is composed of an ultrasonic measurement method.

  According to this, since the instantaneous measurement can be performed, it is possible to measure the details of the change in the flow rate over time, and it is possible to discriminate the appliance with higher accuracy.

  According to a sixth aspect of the present invention, there is provided a step of measuring the flow rate of the fluid flowing in the flow path at a constant time interval, a step of calculating a difference value of the measured flow rate for each predetermined time, and an instrument operation by the measured flow rate. Detected based on a flow rate classification table in which a step of detecting a starting flow rate value, a plurality of differential value categories according to the magnitude of the startup flow rate value and the difference value, and a code representing each category are associated with each other A step of converting the activation flow rate value and the calculated difference value into the code, a step of generating a measurement code string based on the set of the codes for each predetermined time, the measurement code string, The present invention relates to a flow rate measurement method comprising a step of comparing a device-specific code sequence indicating a code sequence and determining a device using a fluid.

  According to this, when discriminating the appliance that uses the fluid, by setting the reference value of the classification of the flow rate classification table to a variable value that is commensurate with the startup flow rate, the flow rate classification can be performed even for instruments having different startup flow rate values. It is not necessary to use a plurality of tables, and a code value obtained by encoding (converting) the difference value of the flow rate based on the same table is used. Accordingly, it is possible to provide a flow rate measurement method capable of suppressing an increase in the amount of memory required for calculation and improving the calculation speed and the accuracy of appliance discrimination when executing appliance discrimination.

  A seventh invention is a program that causes a computer that controls a flow rate measuring device to execute the following steps, the step of measuring the flow rate of a fluid flowing through a flow path at a constant time interval, A step of calculating a difference value for each fixed time; a step of detecting a startup flow value during operation of the appliance from the measured flow rate; and a plurality of difference value categories according to the startup flow value and the magnitude of the difference value; Based on a flow rate classification table in which codes representing each category are associated, a step of converting the detected activation flow rate value and the calculated difference value into the code, and based on the set of codes at the predetermined time A step of generating a measurement code string and a step of comparing the measurement code string with an instrument-specific code string indicating a unique code string for each instrument to determine an instrument that uses fluid. It is intended to be executed by the Yuta.

  According to this, when discriminating the appliance that uses the fluid, by setting the reference value of the classification of the flow rate classification table to a variable value that is commensurate with the startup flow rate, the flow rate classification can be performed even for instruments having different startup flow rate values. It is not necessary to use a plurality of tables, and a code value obtained by encoding (converting) the difference value of the flow rate based on the same table is used. Accordingly, it is possible to provide a program that can suppress an increase in the amount of memory required for calculation and improve the calculation speed and the accuracy of appliance discrimination when executing appliance discrimination.

  The eighth invention particularly relates to a fluid supply system using any one of the first to seventh flow measuring devices, the flow measuring method, or a program executed by a computer.

  According to this, when discriminating the appliance that uses the fluid, by setting the reference value of the classification of the flow rate classification table to a variable value that is commensurate with the startup flow rate, the flow rate classification can be performed even for instruments having different startup flow rate values. It is not necessary to use a plurality of tables, and a code value obtained by encoding (converting) the difference value of the flow rate based on the same table is used. Therefore, it is possible to provide a fluid supply system capable of suppressing an increase in the amount of memory necessary for calculation and improving the calculation speed and the accuracy of instrument discrimination when executing instrument discrimination.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment)
FIG. 1 shows a block diagram of a gas meter as a flow rate measuring apparatus in an embodiment of the present invention.

  In FIG. 1, a gas meter 200 includes a flow path 202, an ultrasonic flow meter 204 as a flow rate measurement unit, a measured flow rate information storage unit 206, a calculation unit 208, an activation flow rate value detection unit 209, and a flow rate classification table holding unit. 210, a difference value conversion unit 212, a code string generation unit 214, a device determination unit 216, and a device specific code string information holding unit 218. Furthermore, the gas meter 200 includes a flow path cutoff valve 222 that is disposed in the flow path 202 and shuts off the gas in an emergency or the like.

  The ultrasonic flowmeter 204 measures the flow rate by emitting ultrasonic waves at a predetermined time interval (for example, 2 seconds) with respect to a gas as a fluid flowing in the flow path 202, and uses a general one. can do. The measured flow rate information storage unit 206 stores the measured flow value measured by the ultrasonic flow meter 204 and target data described in association with the measurement time when the measured flow rate value was measured.

  The calculation unit 208 calculates a difference value for each fixed time corresponding to the above-described ultrasonic wave emission interval of the gas flow rate measured by the ultrasonic flowmeter 204. For example, in FIG. 3 described later, when the flow rate (absolute flow rate) at a predetermined timing is 60 L / h (liters per hour) and the flow rate at the next timing is 120 L / h, the difference value at this time is 120-60 = It is calculated as 60 (L / h). Here, the calculation of the difference value may be performed at the flow rate at the next next timing (the flow rate next to the flow rate of 120 L / h).

  The activation flow value detection unit 209 detects the activation flow value during the operation of the instrument based on the gas flow rate measured by the ultrasonic flowmeter 204. For example, in FIG. 3 to be described later, if the absolute flow rate at the time when the ratio between the flow rate at a predetermined timing (absolute flow rate) and the difference value becomes 1% or less is set as the startup flow rate value, the startup flow rate value at this time is 166 L / h. .

  The flow rate classification table holding unit 210 includes a flow rate classification table 210a in which a plurality of differential value categories corresponding to the startup flow rate value and the size of the differential values and codes representing the respective categories are associated as shown in FIG. It is to hold. The flow rate division table 210a serves as a conversion table that divides the measured difference values into predetermined divisions and converts them into predetermined codes representing the divisions. The number of sections in the flow rate classification table 210a is not particularly limited, but two types of 16 (code N1) and 4 (code N2) are prepared in FIG. That is, the gas meter 200 can be used by appropriately switching between a flow rate classification table with 16 divisions and a flow classification table with 4 divisions.

  As shown in FIG. 2, in the flow rate classification table, two types of classification represented by code N1 and code N2 are prepared. In the code N1, the classification of the flow rate classification table is an area where the flow rate is determined to be zero, an area where the flow rate is determined to be stable (stable area), an area where the flow rate is determined to increase (increase area), and the flow rate. Is divided into four events in a region (decreased region) in which it is determined that the number is decreasing. As shown in the table, these four areas are associated with four numbers of 0, 1, 2, and 3, and can be represented by 2-bit codes. That is, 0 can be expressed as “00”, 1 as “01”, 2 as “10”, and 3 as “11”. In this way, by expressing the classification using a code instead of a conventional difference value, better affinity with the microcomputer program is ensured, and a determination index can be provided with a small memory size and a small amount of calculation.

  In this example, the region in which the flow rate is determined to be zero has been described. However, in an actual apparatus, the actually measured flow rate has a slight variation, and thus it is not often zero. Therefore, the flow rate becomes zero, including when the flow rate is substantially zero and substantially zero.

  The code N2 is generated by further subdividing each of the above-mentioned areas. The stable area is divided into seven according to the degree of flow stability, four according to the degree of increase, and four according to the degree of decrease in the flow. Each is generated by subdividing. The area where the flow rate is judged as zero is not subdivided. Therefore, the code N2 can be expressed by a 4-bit code (0 to 9, A to F).

In the code N1, each region is subdivided with different flow rate intervals. For example, in the increase region, the smaller the difference flow rate, the smaller the interval. For example, in the area of the code “6”, if the starting flow rate value is Qst, the differential flow width is 0.75 × Qst−0.5 × Qst = 0.25 × QstL / h, but the code “4”. In the region of 0.25
× Qst−0.05 × Qst = 0.2 × QstL / h, and in the area of code 3, 0.05 × Qst−0.005 × Qst = 0.045 × QstL / h. Such a configuration is adopted because it is necessary to reduce the interval in order to increase the discrimination accuracy because there are many types of instruments in the region where the differential flow rate is small.

  The difference value conversion unit 212 uses the activation flow rate value detected by the activation flow value detection unit 209 and the difference value calculated by the calculation unit 208 based on the flow rate classification table 210a as a difference at regular intervals (ultrasonic emission). Converts to a code that represents the category into which the value is classified. The code string generation unit 214 generates a measurement code string, which is a code string obtained by actual measurement, based on a set of codes at regular intervals obtained by the difference value conversion unit 212. This measurement code string represents a change in the flow rate of the fluid in a pseudo manner. The code generation unit 214 records the generated measurement code string in a memory (not shown) as necessary.

  The appliance discriminating unit 216 discriminates a gas appliance that uses a gas as a fluid based on the measurement code string generated by the code string generating unit 214. Here, the appliance discriminating unit 216 compares the measurement code string with the instrument-specific code string indicating the gas instrument-specific code string stored in the instrument-specific code string information holding unit 218 in advance for each gas instrument, and the similarity relationship thereof The gas appliance that uses gas is determined from the above.

  The appliance-specific flow rate calculation unit 220 can also calculate the flow rate for each gas appliance determined by the appliance determination unit 216. The gas meter 200 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.

  Hereinafter, a flow rate change history recording method using the gas meter 200 of the present embodiment will be described. First, the flow rate (absolute flow rate) Q (n) measured at a certain time interval (for example, 2 seconds) by the ultrasonic flow meter 204 and the flow rate Q (n−1) measured last time are stored in the measured flow rate information storage. The information is temporarily stored in the unit 106. Thereafter, the calculation unit 208 calculates a difference value ΔQ (n) = Q (n) −Q (n−1) that is a difference between Q (n) and the flow rate Q (n−1) measured last time. Here, the fixed interval may be 4 seconds or 6 seconds.

  The starting flow rate value detection unit 209 calculates a ratio between the flow rate (absolute flow rate) Q (n) stored in the measured flow rate information storage unit 106 and the difference value ΔQ (n) calculated in the calculation unit 208, The absolute flow rate at the time when the ratio (for example, 1%) or less is detected as the starting flow rate value Qst. Here, the predetermined ratio for determining the starting flow rate value may be another value such as 2% or 3%. In addition, when there is no absolute flow value that meets the conditions, for example, the peak value at the start of the instrument or the value when a predetermined time has elapsed since the start of the instrument is used as a substitute for the start flow value. It is good.

  The difference value conversion unit 212 is a code that represents the difference value ΔQ (n) calculated by the calculation unit 208 with reference to the flow rate division table 210a of FIG. It is converted into a code (2-bit code or 4-bit code of N1 or N2). Here, it is possible to freely select which of the division codes N1 and N2 is used. Here, the reference value of the 210a section is obtained by simple ratio calculation with the starting flow rate value, but the reference value may be obtained by calculation of other mathematical formulas including the starting flow rate value. In the mathematical formulas included, a plurality of mathematical formulas may be switched depending on conditions.

FIG. 3 shows an example of conversion using such a flow rate classification table. When a 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” in FIG. Value ”, as shown in the graph of FIG. 3B, 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 ultrasonic flowmeter 204, the calculation unit 208 calculates the difference value, the activation flow value detection unit 209 detects the activation flow value, and the conversion to the category code N1 or the category code N2 is the difference value conversion. This is performed by the unit 212.

  From the code obtained as a result of the conversion, the code string generation unit 214 generates a measurement code string corresponding to the 2-bit code or 4-bit code of “division code N1” and “division code N2” in FIG. . The measurement code sequence obtained by actual measurement, which is a set of codes at regular intervals, is a pseudo representation of a change in the gas flow rate, and the code sequence generation unit 214 obtains the obtained measurement code. Records columns in a memory (not shown) as necessary.

  That is, “classification code N1” and “classification code N2” in FIG. 3A do not represent the flow rate itself as in the “flow rate value” in FIG. 3A and the graph in FIG. Absent. However, such a code string generally changes the gas flow rate, that is, the region where the flow rate is determined to be zero, the region where the flow rate is determined to be stable, the region where the flow rate is determined to increase, and the flow rate decreases. The four events of the area judged to be in a pseudo manner are represented in a pseudo manner, and the change in the behavior of the approximate flow rate can be grasped using the code string.

  FIG. 4 shows an example of conversion using a flow rate classification table of a gas appliance B (for example, a water heater) different from the gas appliance A. Also in the gas appliance B, the classification code N1 ”and“ classification code N2 ”can be obtained in exactly the same procedure as the gas appliance A. Therefore, the change in the behavior of the approximate flow rate can be grasped using the code string in the same manner. It becomes possible.

  Thus, by using the same flow rate classification table 210a for the appliances having different starting flow values such as the gas appliance A and the gas appliance B, the code based on the reference value of the classification corresponding to each starting flow rate value is used. Since the columns can be obtained, it is possible to suppress an increase in the amount of memory necessary for the calculation.

  In addition, when such a measurement code string is unique to each gas appliance, it is possible to determine the gas appliance using the gas.

  Attention is paid to the flow rate change from the start of gas use to a predetermined time, for example, until the third sampling (6 seconds have elapsed). In the example of the gas appliance A in FIG. 3, the classification code N1 (measurement code string) is “0553”. On the other hand, the gas flow rate classification code N1 (measurement code string) until the third sampling is obtained by the gas flow rate after starting the gas appliance B (for example, a water heater) shown in FIG. 0654 ".

  Here, when the codes N1 of the gas appliance A and the gas appliance B are compared, the gas appliance A rises along a unique code string “0553”, and the gas appliance B rises along a unique code string “0654”. A unique code string that is an individual rising characteristic for each gas appliance is stored in advance, and if the classification code N1 that is a measurement code string obtained by measurement and conversion is “0553”, the gas used. It can be determined that the appliance is the gas appliance A. Further, if the classification code N1 that is the obtained measurement code string is “0654”, it can be determined that the used gas appliance is the gas appliance B.

The appliance discriminating unit 216 discriminates a gas appliance using gas by the above-described method based on the measurement code string generated by the code string generating unit 214. Here, the appliance discriminating unit 216 compares the measurement code sequence with the unique code sequence specific to the gas appliance stored in the appliance-specific code sequence information holding unit 218 for each gas appliance in advance, and uses the gas based on the similar relationship. Identify the gas appliance to be used. Similar to N1 and N2 in FIGS. 3 and 4, a code string specific to the gas appliance is stored in advance in the instrument specific code string information holding unit 218. The code string unique to the gas appliance is created in consideration of the codes N1 and N2 corresponding to the differential flow zones in the flow rate classification table 210a shown in FIG.

  In the above-described example, the measurement code string and the instrument specific code string indicate the rising characteristics of the gas instrument A, the gas instrument B,..., That is, the rising characteristics of the flow rate immediately after the start of gas use by the gas instrument. It is. However, there is no particular limitation as long as the gas appliance can be specified, and the measurement code string and the instrument specific code string generally indicate control characteristics (control characteristics of the flow rate) during operation of the gas instrument. Used. The flow rate characteristics during operation of the device include, for example, a flow rate rising characteristic immediately after the start of use of the fluid by the device, a flow rate falling characteristic at the end of use of the fluid, or a flow rate control characteristic during stable use of the fluid. included. Here, the code sequence unique to the gas appliance stored in the appliance specific code sequence information holding unit 218 may be learned and corrected by actual flow measurement instead of being set in advance.

  Further, when attention is paid to the code N2 from the rise (starting time) of the flow rate to a predetermined time (for example, the seventh), the code N2 of the gas appliance A is “01131133” and the code N2 of the gas appliance B is “01113333”. ing. Here, the code N2 is defined as 0: an area where the flow rate is zero, 1: an increasing area, 2: a decreasing area, 3: a stable area, and the gas appliance A rises once and increases temporarily. It is understood from the code N2 of the gas appliance A that there is a characteristic that increases again. On the other hand, it can be understood from the code N2 of the gas appliance B that the gas appliance B has a characteristic that it once rises, continues to increase, and then stabilizes. Therefore, if the code N2 is “01131133”, it is possible to determine the possibility that the gas appliance used is the gas appliance A. If the code N2 is “01113333”, it is possible to determine the possibility that the gas appliance used is the gas appliance B. And the characteristic of the gas appliance A and the characteristic of the gas appliance B can be easily determined by combining the code N1 and the code N2.

  As described above, the measurement code string according to the present invention handles data having a longer measurement time because the memory size is smaller even if the data is the same measurement time as compared to the history of the conventional difference values. Since the same flow rate classification table 210a is used for instruments having different activation flow rate values, it is possible to suppress an increase in the amount of memory required for computation. Therefore, it becomes easy to handle a flow rate change history corresponding to a long measurement time even when determining the appliance. By using a long-term flow rate change history, the accuracy of appliance discrimination can be improved.

  FIG. 5 shows another example of the flow rate classification table 210a. The reference value of the classification in the flow rate classification table of FIG. 5 is a combination of the ratio with the starting flow rate value and the absolute value. For example, if there is a condition such as the flow rate range of the equipment used is within a certain range, the part with a small difference value is considered to be less affected by the startup flow rate value, and the reference value is determined as an absolute value. Since the starting flow rate value has a large influence on the part where the difference value is large, if the reference value is determined based on the ratio to the starting flow rate value, only the necessary part can be obtained by simple calculation. It becomes possible to improve the speed and the accuracy of device discrimination. Here, although the reference value of the classification of the flow rate classification table 210a is obtained by simple ratio calculation with the startup flow value, the reference value may be obtained by calculation of other mathematical formulas including the startup flow value. In a mathematical expression including a flow rate value, a plurality of mathematical expressions may be switched including a portion determined by an absolute value depending on conditions.

In addition to comparing the measurement code string and the unique code string unique to the gas appliance stored in the instrument unique code string information holding unit 218 in advance for each gas instrument, the appliance discrimination unit 216 of the present invention is also provided with an activation flow rate. By comparing the starting flow rate value detected by the value detection unit 209 with the unique starting flow rate value for each appliance, and determining the gas appliance that uses gas from its similarity, etc., only the comparison of code strings Then, even if it is difficult to discriminate, it becomes possible to discriminate more accurately by combining the comparison of the startup flow rate values. Here, the unique starting flow rate value for each instrument may be additionally stored in the instrument-specific code string information holding unit 218, or may be separately stored in another information holding unit (not shown). Further, here, the starting flow rate value unique to each instrument may be either an absolute value of the starting flow rate value and a value added with an allowable range thereof, or a value obtained by coding the starting flow rate value.

  In order to carry out the flow rate measuring method as described above, the instrument discriminating unit 216 of the gas meter 200 and a computer (arithmetic unit) (not shown) store programs for executing the steps of the flow rate measuring method. In addition, a fluid supply system including a fluid (gas) supply source using a flow measurement device, a flow measurement method, and a program executed by a computer of the present invention is also included in the present invention.

  Although the above explanation has been given for the case where an ultrasonic flowmeter is used, it is obvious that the same effect can be obtained with other instantaneous flow measurement devices using a sampling signal. The processing after the device identification is omitted, but in the gas meter, the fee for each device by measuring the accumulated flow rate for each registered device or each classified group, and the safety management for each registered device or each classified group ( It is obvious that it is possible to set a security function for each device of the processing. In addition, if the gas meter and the gas appliance can be equipped with transmission / reception means such as a radio, it is clear that the accuracy of appliance discrimination is further improved. Furthermore, although it demonstrated with the gas meter and the gas appliance, it can use for the specification of the use appliance connected to the downstream of the flow measuring device, and its grouping similarly in an industrial flowmeter and a water meter.

  Further, in the above-described embodiment, the flow rate rising characteristic immediately after the start of use of the instrument is set as a coding target. However, the encoding target of the present invention is not limited to the rising characteristics of the flow rate immediately after the start of use of the appliance, but includes a wide range of flow rate changes such as the falling characteristics of the flow rate at the end of use of the appliance and the control characteristics of the flow rate when using the appliance. It can be grasped as the general characteristics of

  Further, in the above-described embodiment, the difference value of the flow rate of the gas, which is a fluid, is the object to be coded. However, the encoding target of the present invention is not limited to the difference value of the flow rate, and can be widely grasped as the physical quantity of the fluid such as the absolute value of the flow rate, the temperature, pressure, and mass of the fluid.

  Although various embodiments of the present invention have been described above, the present invention is not limited to the matters shown in the above-described embodiments, and those skilled in the art can make modifications and applications based on the description and well-known techniques. This is also the scope of the present invention, and is included in the scope for which protection is sought.

  As described above, according to the present invention, in order to convert the difference value into a code that is easier to handle, it is possible to reduce the amount of memory required for the apparatus and provide the calculation speed and the instrument while providing the discrimination technique of the fluid use instrument. It becomes possible to improve the discrimination accuracy.

Block diagram of a gas meter in an embodiment of the present invention The figure which shows an example of the flow volume division table of this invention (A) The figure which shows the concept which classifies the difference value of the starting flow rate value and flow volume by use of gas appliance A according to a flow rate division table (b) The figure which shows the time transition of the startup flow value value by use of gas appliance A (A) The figure which shows the concept which classifies the difference value of the starting flow rate value and flow volume by use of gas appliance B according to a flow rate division table (b) The figure which shows the time transition of the startup flow value value by use of gas appliance B The figure which shows the other example of the flow rate division table | surface of this invention Block diagram of a conventional gas meter Figure showing an example of a conventional flow rate classification table

13, 14, 15 Gas appliance 19 Gas pipe line 200 Gas meter (flow rate measuring device)
202 Flow path 204 Ultrasonic flow meter 206 Measurement flow rate information storage unit 208 Calculation unit 209 Start flow rate value detection unit 210 Flow rate classification table holding unit 212 Difference value conversion unit 214 Code string generation unit 216 Instrument discrimination unit 218 Instrument specific code string information storage Unit 220 flow rate calculation unit for each instrument 222 flow path shut-off valve

Claims (8)

A flow rate measurement unit for measuring the flow rate of the fluid flowing in the flow path at regular time intervals;
A calculation unit that calculates a difference value of the flow rate measured by the flow rate measurement unit for each predetermined time; and
A starting flow rate value detecting unit that detects a starting flow rate value at the time of operation of the instrument based on the flow rate measured by the flow rate measuring unit;
A difference value divided into a plurality of reference values determined according to the magnitude of the starting flow rate value;
A flow rate classification table associated with codes representing each classification;
A difference value conversion unit that converts the activation flow value detected by the activation flow value detection unit and the difference value calculated by the calculation unit into the code based on the flow rate classification table;
A code string generation unit that generates a measurement code string based on the set of codes for each predetermined time obtained by the difference value conversion unit;
An instrument discriminating unit that compares the measurement code string and an instrument-specific code string indicating a unique code string for each instrument, and discriminates an instrument that uses fluid;
A flow rate measuring device comprising: The flow rate measuring device according to claim 1,
The flow rate measuring apparatus according to claim 1, wherein the reference value of the classification of the flow rate classification table is determined by a ratio with the starting flow rate value. The flow rate measuring device according to claim 1,
The reference value of the classification of the flow rate classification table is determined by a combination of a ratio with an activation flow value and an absolute value. It is a flow measuring device given in any 1 paragraph of Claims 1-3,
In addition to comparing the measurement code string and the instrument-specific code string indicating a unique code string for each instrument, the instrument determination unit includes the activation flow value detected by the activation flow value detection unit and the instrument-specific code string. The flow rate measuring device characterized by comparing the starting flow rate values of the two, and discriminating an instrument that uses the fluid. The flow rate measuring device according to any one of claims 1 to 4,
The flow rate measuring unit is a flow rate measuring device comprising an ultrasonic measurement method. Measuring the flow rate of the fluid flowing in the flow path at regular time intervals;
A step of calculating a difference value of the measured flow rate for each predetermined time;
A step of detecting a starting flow rate value during operation of the instrument from the measured flow rate; and
Based on a flow rate classification table in which a plurality of differential value categories according to the size of the startup flow rate value and the difference value and a code representing each category are associated, the detected startup flow rate value and the calculated difference value are Converting to the code;
Generating a measurement code string based on the set of codes at the predetermined time;
Comparing the measurement code string with an instrument-specific code string indicating a unique code string for each instrument, and determining an instrument that uses fluid;
A flow measurement method comprising: A program for controlling a flow measuring device to execute the following steps,
Measuring the flow rate of the fluid flowing in the flow path at regular time intervals;
A step of calculating a difference value of the measured flow rate for each predetermined time;
A step of detecting a starting flow rate value at the time of instrument operation based on the measured flow rate, a plurality of difference value categories according to the starting flow rate value and the size of the difference value, and a flow rate associated with a code representing each category Converting the detected starting flow rate value and the calculated difference value into the code based on the classification table;
Generating a measurement code string based on the set of codes at the predetermined time;
Comparing the measurement code string with an instrument-specific code string indicating a unique code string for each instrument, and determining an instrument that uses fluid;
A program that causes a computer to execute. A fluid supply system using the flow rate measuring device or the flow rate measuring method according to claim 1, or a program executed by a computer.