JP6083664B2 - Flow measuring device - Google Patents

Description

  The present invention relates to a flow rate measuring device that measures the flow rate of a fluid such as a gas.

  Currently, a gas meter for measuring the amount of gas used is installed in a gas pipe in a general gas consumer's house. As the gas meter, a membrane gas meter, an ultrasonic gas meter, and the like are known. The membrane gas meter measures the gas flow rate by the number of times it passes through the measuring chamber. The ultrasonic gas meter is equipped with ultrasonic sensors upstream and downstream of the flow path through which the gas flows, and measures the flow velocity of the gas flowing through the flow path using the arrival time of the ultrasonic wave. Is used to measure the amount of gas used.

  By the way, in an ultrasonic gas meter or the like, for example, when a gas engine is operated nearby, a pressure fluctuation occurs, and the flow rate in the gas pipe fluctuates periodically. In order to solve such a problem, a flow rate measuring device aimed at maintaining and improving measurement accuracy and realizing low power consumption is known (see, for example, Patent Document 1).

  The flow rate measuring device disclosed in Patent Document 1 is an integer N times the fluctuation period and the length of the fluctuation period so that the number of measurements performed by the measurement period changing unit within one measurement period is substantially equal. By setting the number of periods inversely proportional to the measurement period, the measurement accuracy is maintained and improved when the fluctuation period is short, and the power consumption is low when the fluctuation period is long.

  In addition, there is known a flow rate measuring device in which a flow rate measuring unit is provided in each of a plurality of channels arranged in parallel for the purpose of measuring from a large flow rate to a small flow rate (see, for example, Patent Document 2). ).

Patent No. 4008266 Japanese Patent No. 4174878

  However, neither of the inventions disclosed in Patent Documents 1 and 2 considers a case where flow rate measuring means is arranged in a plurality of flow paths and the flow rate fluctuates periodically in the flow paths.

  The present invention has been made in view of the above problems, and by arranging flow rate measuring devices in a plurality of flow paths, even if the flow rate fluctuates periodically in the flow paths, the measurement accuracy of the total flow rate of the fluid is improved. An object of the present invention is to provide a flow rate measuring device that can be used.

  In order to solve the above-described conventional problems, a flow rate measuring device according to the present invention is provided in each of a plurality of flow paths provided between an inlet and an outlet and each of the flow paths. A flow rate measuring device that measures the flow rate of the flowing fluid, and a flow rate calculator that calculates the total flow rate of the fluid flowing between the inlet and the outlet from the flow rate measured by the flow rate measuring device, Each of the flow rate measuring devices is configured to perform measurement of the flow rate of the fluid a predetermined number of times within a first period in which start times coincide with each other, and two or more of the flow rate measuring devices are first in the first period. The timing for executing the fluid flow rate measurement is different from each other.

  As a result, even if the flow rate fluctuates periodically in the flow path, the influence of the periodic fluctuation of the flow rate can be reduced by shifting the timing for measuring the flow rate of the fluid. The measurement accuracy of the total flow rate can be improved.

  The flow rate measuring device according to the present invention measures a flow rate of a plurality of flow paths provided between an inflow port and an outflow port, and a fluid that is provided in each of the flow paths and flows through the flow path. A flow rate measuring device, and a flow rate calculating unit that calculates a total flow rate of fluid flowing between the inlet and the outlet from the flow rate measured by the flow rate measuring device, and each of the flow rate measuring devices starts The flow rate measurement of the fluid is performed a predetermined number of times within a first period in which the times coincide with each other, and the two or more flow rate measuring devices perform the measurement of the flow rate of the fluid within the first period. The intervals are different from each other.

  As a result, even if the flow rate fluctuates periodically in the flow path, the influence of the cyclic fluctuation of the flow rate can be reduced by shifting the interval for measuring the flow rate of the fluid. The measurement accuracy of the total flow rate can be improved.

  Furthermore, the flow rate measuring device according to the present invention measures a flow rate of a plurality of flow paths provided between an inflow port and an outflow port, and a fluid that is provided in each of the flow paths and flows through the flow path. A flow rate measuring device, and a flow rate calculating unit that calculates a total flow rate of a fluid flowing between the inlet and the outlet from the flow rate measured by the flow rate measuring device, and each of the flow rate measuring devices includes: The start time of the first period is configured to coincide with each other, and the two or more flow rate measuring devices have a length of a second period that is a period in which the flow rate measurement of the fluid in the first period is executed a predetermined number of times. Each is configured differently.

  As a result, even if the flow rate periodically fluctuates in the flow path, the influence of the periodic fluctuation of the flow rate can be reduced by shifting the length of the second period in which the fluid flow rate is measured within the first period. As a result, the measurement accuracy of the total fluid flow rate can be improved.

  According to the flow rate measuring device according to the present invention, it is possible to reduce the influence of periodic fluctuations in the flow rate, and as a result, it is possible to improve the measurement accuracy of the total flow rate of the fluid.

FIG. 1 is a schematic diagram showing a schematic configuration of the flow rate measuring apparatus according to the first embodiment. FIG. 2 is a schematic diagram showing a configuration of a flow rate measuring device in the flow rate measuring apparatus shown in FIG. FIG. 3 is a graph showing the relationship between the fluctuation cycle of the fluid flow and the measurement cycle in the flow rate measuring apparatus according to the first embodiment. FIG. 4 is a graph showing the relationship between the fluctuation cycle of the fluid flow and the measurement cycle in the flow rate measurement device according to the second embodiment. FIG. 5 is a graph showing the relationship between the fluctuation cycle of the fluid flow and the measurement cycle in the flow rate measurement device according to the third embodiment. FIG. 6 is a graph showing the relationship between the fluctuation cycle of the fluid flow and the measurement cycle in the flow rate measurement device of the present modification.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted. In all the drawings, components necessary for explaining the present invention are extracted and shown, and other components may be omitted.

(Embodiment 1)
The flow rate measuring apparatus according to the first embodiment is provided in each of a plurality of flow paths provided between the inlet and the outlet, and the flow path of the fluid flowing through the flow path for each first period. A flow rate measuring device for measuring the flow rate, and a flow rate calculating unit for calculating a total flow rate of the fluid flowing between the inlet and the outlet from the flow rate measured by the flow rate measuring device. The start point of one period is the same and the flow rate of the fluid is measured a predetermined number of times within the first period, and the two or more flow rate measuring devices are configured to measure the flow rate of the first fluid within the first period. The aspect which is comprised so that the timing which performs a measurement may differ, respectively is illustrated.

  Hereinafter, an example of the flow rate measuring apparatus according to the first embodiment will be described with reference to FIGS. 1 to 3.

[Configuration of flow measurement device]
FIG. 1 is a schematic diagram showing a schematic configuration of the flow rate measuring apparatus according to the first embodiment.

  As shown in FIG. 1, the flow rate measuring device 100 according to the first embodiment is installed in the middle of a gas pipe, and a plurality of (here, three) are provided between the inlet 1 and the outlet 2. ), The flow rate measuring devices 4A to 4C for measuring the flow rate of the fluid flowing through each of the flow channels 3A to 3C, and the total flow rate of the fluid flowing between the inlet 1 and the outlet 2 And a main controller (flow rate calculator) 5 for calculating.

  The inflow port 1 is an entrance for flowing gas into the flow rate measuring device 100, and is connected to a gas pipe on the gas supply source side. An inlet buffer unit 6 communicates with the inflow port 1. The inlet buffer unit 6 is a space for diverting the gas that has flowed into the inlet buffer unit 6 from the inlet 1 into the flow paths 3A to 3C.

  A blocking mechanism 7 is provided in the middle of the inlet buffer unit 6. The blocking mechanism 7 is configured to block the flow of gas from the gas supply source side to the gas consumption source side. The shut-off mechanism 7 may be configured by, for example, a valve body that closes the flow path that forms the inlet buffer unit 6 and a stepping motor that drives the valve body. Since such a blocking mechanism 7 is well known, detailed description thereof is omitted.

  Further, the outlet 2 is an outlet for allowing the gas flowing into the flow rate measuring device 100 to flow out to the gas pipe on the gas consumption source side. An outlet buffer unit 8 communicates with the outlet 2. The outlet buffer unit 8 is a space for joining the gases that have flowed through the flow paths 3A to 3C. By the inlet buffer unit 6 and the outlet buffer unit 8, the flow velocity and flow rate of the gas flowing through the flow paths 3A to 3C can be made uniform.

  The flow paths 3 </ b> A to 3 </ b> C are provided to communicate the inlet buffer unit 6 and the outlet buffer unit 8. The flow paths 3A to 3C may be formed so that the cross-sectional areas of the flow paths are the same or different from each other. Moreover, in this Embodiment 1, although the form which arrange | positions a flow measuring device was employ | adopted for each of the flow paths 3A-3C, it is not limited to this, The flow measuring device is arrange | positioned in any flow path. No form may be employed.

  The flow rate measuring devices 4A to 4C are configured to measure the flow rate of the fluid flowing through each of the flow paths 3A to 3C using sensors such as an ultrasonic sensor, a thermal flow sensor, and a fluidic sensor, for example. ing. In the first embodiment, the flow rate measuring device 4A uses an ultrasonic sensor.

  Here, the configuration of the flow rate measuring device 4A will be described in more detail with reference to FIG. Since the flow rate measuring device 4B and the flow rate measuring device 4C are configured in the same manner as the flow rate measuring device 4A, detailed description thereof is omitted.

  FIG. 2 is a schematic diagram showing a configuration of a flow rate measuring device in the flow rate measuring apparatus shown in FIG.

  As shown in FIG. 2, the flow rate measuring device 4 </ b> A includes an upstream ultrasonic sensor 11, a downstream ultrasonic sensor 12, and a sub controller 13.

  The upstream ultrasonic sensor 11 and the downstream ultrasonic sensor 12 are configured to transmit and receive ultrasonic waves to each other and to be driven according to a control instruction from the sub-controller 13. The upstream ultrasonic sensor 11 is provided on the upstream side wall of the flow path 3A, and the downstream ultrasonic sensor 12 is provided on the downstream side wall of the flow path 3A. The side ultrasonic sensors 12 are disposed so as to face each other.

  The sub-controller 13 includes a calculator 13A and a memory 13B, and is configured to control the upstream ultrasonic sensor 11 and the downstream ultrasonic sensor 12. As the arithmetic unit 13A, an LSI (Large Scale Integration) or the like can be used. Further, as the memory 13B, for example, a semiconductor storage device such as a readable / writable RAM or ROM can be cited.

  Then, the arithmetic unit 13A controls the upstream ultrasonic sensor 11 and the downstream ultrasonic sensor 12 based on the control signal from the main controller 5, and calculates the flow rate of the gas flowing through the flow path 3A. The flow rate is output to the main controller 5.

  Specifically, the sub-controller 13 causes each of the upstream ultrasonic sensor 11 and the downstream ultrasonic sensor 12 to output an ultrasonic wave, and the output ultrasonic wave is transmitted to the downstream ultrasonic sensor 12 and the upstream ultrasonic sensor. The time required to reach each of the sound wave sensors 11 is measured. Then, the sub-controller 13 calculates the flow velocity of the gas flowing through the flow path 3A from the difference in arrival time, and multiplies the calculated flow velocity of the gas by the cross-sectional area of the flow path 3A, thereby flowing the gas flowing through the flow path 3A. The flow rate is calculated.

  The main controller 5 includes an arithmetic processing unit exemplified by a microprocessor, a CPU, and the like, and a storage unit configured by a memory or the like that stores a program for executing each control operation (both shown in FIG. 1). (Not shown). The main controller 5 calculates the total flow rate of the gas flowing between the inlet 1 and the outlet 2 based on the flow rates of the flow paths 3A to 3C input from the flow rate measuring devices 4A to 4C. .

  In the first embodiment, the sub controller 13 calculates the flow rate of the gas flowing through the flow path, and the main controller 5 sends the total flow rate of the gas flowing between the inlet 1 and the outlet 2. However, the present invention is not limited to this. For example, the sub controller 13 measures the arrival time of the ultrasonic wave, outputs the measured arrival time to the main controller 5, and the main controller 5 calculates the flow rate of each flow path, and calculates the total flow rate. You may employ | adopt the form to calculate. Alternatively, the sub controller 13 may estimate the total flow rate from the calculated flow rate of the flow path, and output the estimated total flow rate to the main controller 5. The estimation of the total flow rate by the sub controller 13 can be performed by multiplying the calculated flow rate by three, for example, since there are three flow paths in the first embodiment.

  The main controller 5 and the flow rate measuring devices 4 </ b> A to 4 </ b> C are supplied with power from the battery 14. Further, the battery 14 supplies power to the stepping motor of the shut-off mechanism 7. Further, the main controller 5 causes the display 15 to display the flow rate of each of the flow paths 3A to 3C and / or the total flow rate of the gas flowing between the inlet 1 and the outlet 2. Examples of the display 15 include a CRT, a liquid crystal display, a plasma display, an organic EL display, and the like.

[Operation of flow measurement device]
Next, the operation of the flow rate measuring apparatus 100 according to the first embodiment will be described with reference to FIGS. 1 to 3.

  FIG. 3 is a graph showing the relationship between the fluctuation cycle of the fluid flow and the measurement cycle in the flow rate measuring apparatus according to the first embodiment.

  First, it is assumed that the fluid flowing through each of the flow paths 3A to 3C of the flow rate measuring device 100 is flowing at the fluctuation period shown in FIG. 3 (see the graph where the vertical axis indicates the flow rate and the horizontal axis indicates time). Moreover, each flow volume measuring device 4A-4C is comprised so that the flow volume of the fluid which flows through each flow path 3A-3C for every 1st period P1 may be measured. The flow rate measuring devices 4A to 4C are synchronized by a common clock input from the main controller 5, and the start points (start times) of the first period P1 coincide with each other. Further, each of the flow rate measuring devices 4A to 4C is configured to measure the flow rate a predetermined number of times within the first period P1.

  The main controller 5 instructs each of the flow rate measuring devices 4A to 4C to measure the flow rate of the fluid at time t0 that is the start point of the first period P1. Each of the flow rate measuring devices 4A to 4C (more precisely, the sub-controller 13) receives the instruction and measures the flow rate as follows.

  The flow rate measuring device 4A outputs ultrasonic waves from the upstream ultrasonic sensor 11 and the downstream ultrasonic sensor 12 after a predetermined time Ta from the start of the first period P1 (time tA1 in FIG. 3), and the flow path The flow rate of the fluid flowing through 3A is measured. Then, the flow rate measuring device 4A measures the flow rate of the fluid flowing through the flow path 3A every predetermined interval ISa (time tA2, time tA3, and time tA4) a predetermined number of times (here, a total of 4 times), After the measurement, the measured fluid flow rate is output to the main controller 5. Note that a period during which the flow rate measuring device 4A performs flow rate measurement a predetermined number of times within the first period (a period from the measurement start time at time tA1 to the measurement end time at time tA4) is referred to as a second period PA here. .

  Similarly, the flow rate measuring device 4B measures the flow rate of the fluid flowing through the flow path 3B after a predetermined time Tb (time tB1 in FIG. 3). Then, the flow rate measuring device 4B measures the flow rate of the fluid flowing through the flow path 3B at a predetermined number of times (here, a total of 4 times) at every predetermined interval ISb (time tB2, time tB3, and time tB4). After the measurement, the measured fluid flow rate is output to the main controller 5. Note that a period in which the flow rate measuring device 4B executes the flow rate measurement a predetermined number of times within the first period is referred to herein as a second period PB.

  Further, the flow rate measuring device 4C measures the flow rate of the fluid flowing through the flow path 3C after a predetermined time Tc (time tC1 in FIG. 3). Then, the flow rate measuring device 4C measures the flow rate of the fluid flowing through the flow path 3C at a predetermined number of times (here, a total of 4 times) at every predetermined interval ISc (time tC2, time tC3, and time tC4), After the measurement, the measured fluid flow rate is output to the main controller 5. Note that a period during which the flow rate measuring device 4C executes the flow rate measurement a predetermined number of times within the first period is referred to herein as a second period PC.

  Here, as shown in FIG. 3, by setting the predetermined time Ta <predetermined time Tb <predetermined time Tc, each of the flow rate measuring devices 4A to 4C has a timing for measuring the flow rate of the first fluid in the first period. Different. Thereby, even if the flow rate fluctuates periodically in the flow path, the influence of the periodic fluctuation of the flow rate can be reduced, and as a result, the measurement accuracy of the total flow rate of the fluid can be improved.

  Moreover, in this Embodiment 1, by making the space | interval measured in each flow volume measuring device 4A-4C the same (predetermined interval ISa = predetermined interval ISb = predetermined interval ISc), each flow volume measuring device 4A-4C is The timings for measuring the flow rate of the fluid in the first period are all different. Thereby, even if the flow rate fluctuates periodically in the flow path, the influence of the periodic fluctuation of the flow rate can be reduced, and as a result, the measurement accuracy of the total flow rate of the fluid can be improved.

  Then, the main controller 5 calculates the total flow rate of the fluid flowing from the inlet 1 to the outlet 2 from the flow rates of the respective flow paths 3A to 3C measured by the flow rate measuring devices 4A to 4C. The total flow rate may be calculated, for example, by obtaining an average value of four flow rates measured by each of the flow rate measuring devices 4A to 4C and integrating the average value.

  Next, when the time t1, which is the start point of the next first period P1, is reached, the main controller 5 instructs the flow rate measuring devices 4A to 4C to measure the flow rate of the fluid again, and repeats the above operation. In this way, the main controller 5 calculates the total flow rate of the fluid flowing between the inlet 1 and the outlet 2 for each first period P1.

  In the flow rate measuring apparatus 100 according to the first embodiment configured as described above, the timing of measuring the flow rate of the first fluid in the first period P1 of each of the flow rate measuring instruments 4A to 4C is different. The influence of periodic fluctuations can be reduced, and as a result, the measurement accuracy of the total fluid flow rate can be improved.

  In the first embodiment, the main controller 5 employs a mode in which the flow rate measuring devices 4A to 4C are instructed to measure the flow rate of the fluid when the time that is the starting point of the first period P1 is reached. However, it is not limited to this. For example, the flow rate measuring devices 4A to 4C are configured to measure the flow rate a predetermined number of times at predetermined intervals ISa, ISb, and ISc, respectively, and the main controller 5 determines the predetermined time Ta from the start point of the first period P1. , Tb, and Tc may be used to instruct the flow rate measuring devices 4A to 4C to measure the fluid flow rate, respectively.

  In addition, for example, the flow rate measuring devices 4A to 4C are configured to measure the flow rate based on an instruction from the main controller 5, and the main controller 5 performs the predetermined time Ta from the start point of the first period P1. , Tb, and Tc, after the elapse of time, an instruction to measure the flow rate is output to each of the flow rate measuring devices 4A to 4C, and then the predetermined number of times for each of the predetermined intervals ISa, ISb, ISc, A mode of outputting an instruction to measure the value may be adopted.

  In the first embodiment, all of the flow rate measuring devices 4A to 4C adopt a mode in which the timing for measuring the first fluid flow rate in the first period P1 is different, but the present invention is not limited to this. As long as the above timing is different in two or more flow rate measuring devices among a plurality (three in this case) of flow measuring devices, any form may be used.

  Furthermore, the flow rate measuring device 100 according to the first embodiment detects the fluctuation cycle of the flow rate generated in the flow path with a pressure detector or the like, and the flow rate measuring devices 4A to 4C of the flow rate measuring devices 4A to 4C are detected according to the length of the fluctuation cycle. You may change the timing which measures the flow volume of the first fluid within 1 period. That is, the predetermined times Ta, Tb, and Tc for determining the timing may be predetermined fixed values, or may be changed as appropriate according to the fluid pressure fluctuation period.

(Embodiment 2)
The flow rate measuring device according to the second embodiment is provided in each of a plurality of flow paths provided between the inlet and the outlet, and the flow path of the fluid flowing through the flow path for each first period. A flow rate measuring device for measuring the flow rate, and a flow rate calculating unit for calculating a total flow rate of the fluid flowing between the inlet and the outlet from the flow rate measured by the flow rate measuring device. The start point of one period is the same, and the flow rate of the fluid is measured a predetermined number of times within the first period, and the two or more flow rate measuring instruments measure the flow rate of the fluid within the first period. The mode which is comprised so that the space | interval to perform may each differ may be illustrated.

  Note that the flow rate measuring device 100 according to the second embodiment has the same configuration as the flow rate measuring device 100 according to the first embodiment, and thus a detailed description of the configuration is omitted.

[Operation of flow measurement device]
FIG. 4 is a graph showing the relationship between the fluctuation cycle of the fluid flow and the measurement cycle in the flow rate measurement device according to the second embodiment.

  First, it is assumed that the fluid flowing through each of the flow paths 3A to 3C of the flow rate measuring device 100 flows at the same cycle as the fluctuation cycle shown in FIG. 3 (see FIGS. 3 and 4). Moreover, each flow measuring device 4A-4C measures the flow volume of the fluid which flows through each flow path 3A-3C for every 1st period P1, the starting point of 1st period P1 is common, and 1st period P1 It is configured to measure the flow rate a predetermined number of times.

  As shown in FIG. 4, the operation of the flow measurement device 100 according to the second embodiment is the same as the operation of the flow measurement device 100 according to the first embodiment, but the first operation in the first period is the same. The difference is that the timing at which the flow rate of the fluid is measured is the same, and that the intervals measured by the flow rate measuring devices 4A to 4C in the first period are different. More specifically, the flow rate measuring device 4A performs the same operation as the flow rate measuring device 100 according to Embodiment 1, but the flow rate measuring devices 4B and 4C perform the following operations.

  The flow rate measuring device 4B measures the flow rate of the fluid flowing through the flow path 3B after a predetermined time Tb (time tB1 in FIG. 4). Then, the flow rate measuring device 4B passes through the flow path 3B every predetermined interval ISb (time tB2, time tB3, time tB4, time tB5, time tB6, and time tB7) a predetermined number of times (here, a total of 7 times). The flow rate of the flowing fluid is measured, and after the measurement, the measured fluid flow rate is output to the main controller 5.

  The flow rate measuring device 4C measures the flow rate of the fluid flowing through the flow path 3C after a predetermined time Tc (time tC1 in FIG. 4). Then, the flow rate measuring device 4C is set at a predetermined number of times (here, total tC2, time tC3, time tC4, time tC5, time tC6, time tC7, time tC8, time tC9, and time tC10) (here, total) 10 times), the flow rate of the fluid flowing through the flow path 3C is measured, and after the measurement, the measured flow rate of the fluid is output to the main controller 5.

  As described above, in the flow rate measuring device 100 according to the second embodiment, even when the timing (time tA1, time tB1, and time tC1) for measuring the flow rate of the first fluid in the first period P1 is the same, The flow rate measuring devices 4A to 4C are configured so that the intervals at which the flow rate is measured are different (in this embodiment, the predetermined interval ISa> the predetermined interval ISb> the predetermined interval ISc), so that each of the flow rate measuring devices 4A to 4C The timing for measuring the flow rate of the fluid in the period P1 can be varied. Thereby, even if the flow rate fluctuates periodically in the flow path, the influence of the periodic fluctuation of the flow rate can be reduced, and as a result, the measurement accuracy of the total flow rate of the fluid can be improved.

  In addition, in the flow measuring device 100 which concerns on this Embodiment 2, although the timing which measures the flow volume of the first fluid in each 1st period P1 of each flow measuring device 4A-4C was employ | adopted, it is limited to this. Not. As in the flow rate measuring device 100 according to the first embodiment, a mode in which the timing of measuring the first fluid flow rate in the first period P1 of each of the flow rate measuring devices 4A to 4C may be adopted.

  Moreover, in this Embodiment 2, each flow measuring device 4A-4C employ | adopts the form which makes the space | interval which measures a flow flow respectively a predetermined fixed value (predetermined interval ISa, predetermined interval ISb, and predetermined interval ISc). However, it is not limited to this. If each of the flow rate measuring devices 4A to 4C can change the timing for measuring the flow rate of the fluid in the first period P1, each of the flow rate measuring devices 4A to 4C may adopt a form in which the flow rate measurement intervals are different. Good. That is, for example, the flow rate measuring device 4A may measure the flow rate so that the interval between tA1 and tA2 is different from the interval between tA2 and tA3 (length of time). .

(Embodiment 3)
The flow rate measuring device according to the third embodiment is provided in each of a plurality of flow paths provided between the inflow port and the outflow port, and the flow path of the fluid flowing through the flow path for each first period. A flow rate measuring device for measuring the flow rate, and a flow rate calculating unit for calculating a total flow rate of the fluid flowing between the inlet and the outlet from the flow rate measured by the flow rate measuring device. The start points of one period are configured to be the same, and the two or more flow rate measuring devices have different lengths of the second period, which is a period in which the flow rate measurement of the fluid in the first period is executed a predetermined number of times. It is an example of a configured aspect.

  Further, in the flow rate measuring apparatus according to the third embodiment, two or more flow rate measuring devices may be configured such that the intervals at which the fluid flow rate is measured in the first period are different.

  Note that the flow rate measuring device 100 according to the third embodiment has the same configuration as the flow rate measuring device 100 according to the first embodiment, and thus a detailed description of the configuration is omitted.

[Operation of flow measurement device]
FIG. 5 is a graph showing the relationship between the fluctuation cycle of the fluid flow and the measurement cycle in the flow rate measurement device according to the third embodiment.

  First, it is assumed that the fluid flowing through each of the flow paths 3A to 3C of the flow rate measuring device 100 flows in the same cycle as the fluctuation cycle shown in FIG. 3 (see FIGS. 3 and 5). Moreover, each flow measuring device 4A-4C measures the flow volume of the fluid which flows through each flow path 3A-3C for every 1st period P1, the starting point of 1st period P1 is common, and 1st period P1 It is configured to measure the flow rate a predetermined number of times.

  As shown in FIG. 5, the operation of the flow measuring device 100 according to the third embodiment is the same as the operation of the flow measuring device 100 according to the first embodiment, but the flow measuring devices 4A to 4C. The timing of measuring the first fluid flow rate in the first period P1 is the same, and the length of the second period PA to PC, which is a period in which the measurement of the fluid flow rate in the first period P1 is executed a predetermined number of times. Are different and different.

  More specifically, the flow rate measuring device 4A performs the same operation as the flow rate measuring device 100 according to the first embodiment, but the flow rate measuring devices 4B and 4C perform measurement of the flow rate of the fluid within the first period. The intervals (predetermined intervals ISb and ISc) are different from the predetermined interval ISa in the flow rate measuring device 4A. Specifically, the flow rate measuring devices 4A to 4C measure the flow rate so that the predetermined interval ISa <the predetermined interval ISb <the predetermined interval ISc. In the third embodiment, the flow rate measuring devices 4A to 4C are configured so that the number of times of measurement of the flow rate of the fluid in the first period P1 is the same (here, 4 times in total). Has been.

  Thus, in the flow rate measuring device 100 according to the third embodiment, the flow rate measuring devices 4A to 4C change the second period by changing the interval at which the fluid flow rate is measured in the first period P1. Thereby, the timing which measures the flow volume of the fluid in the 1st period P1 can be changed. Thereby, even if the flow rate fluctuates periodically in the flow path, the influence of the periodic fluctuation of the flow rate can be reduced, and as a result, the measurement accuracy of the total flow rate of the fluid can be improved.

  In addition, in the flow measuring device 100 which concerns on this Embodiment 3, although the timing which measures the flow volume of the first fluid in the 1st period P1 of each flow measuring device 4A-4C was employ | adopted, it is limited to this. Not. As in the flow rate measuring device 100 according to the first embodiment, a mode in which the timing of measuring the first fluid flow rate in the first period P1 of each of the flow rate measuring devices 4A to 4C may be adopted.

  In the third embodiment, each of the flow rate measuring devices 4A to 4C adopts a mode in which the flow rate measurement intervals are set to predetermined fixed values (predetermined interval ISa, predetermined interval ISb, and predetermined interval ISc). However, it is not limited to this. If each of the flow rate measuring devices 4A to 4C can change the timing for measuring the flow rate of the fluid in the first period P1, each of the flow rate measuring devices 4A to 4C may adopt a form in which the flow rate measurement intervals are different. Good. That is, for example, the flow rate measuring device 4A may measure the flow rate so that the interval between tA1 and tA2 is different from the interval between tA2 and tA3 (length of time). .

[Modification]
Next, a modification of the flow rate measuring device according to the third embodiment will be described.

  The flow rate measuring device of the modification in the third embodiment exemplifies an aspect in which two or more flow rate measuring devices are configured to have different numbers of times of measuring the flow rate of the fluid. Note that the flow measurement device 100 of the present modification has the same configuration as that of the flow measurement device 100 according to Embodiment 3, and therefore a detailed description of the configuration is omitted.

[Operation of flow measurement device]
FIG. 6 is a graph showing the relationship between the fluctuation cycle of the fluid flow and the measurement cycle in the flow rate measurement device of the present modification.

  First, it is assumed that the fluid flowing through each of the flow paths 3A to 3C of the flow rate measuring device 100 flows in the same cycle as the fluctuation cycle shown in FIG. 3 (see FIGS. 3 and 6). Moreover, each flow measuring device 4A-4C measures the flow volume of the fluid which flows through each flow path 3A-3C for every 1st period P1, the starting point of 1st period P1 is common, and 1st period P1 It is configured to measure the flow rate a predetermined number of times.

  As shown in FIG. 6, the operation of the flow rate measuring device 100 of the present modification is the same as that of the flow rate measuring device 100 according to Embodiment 3, but the first of the flow rate measuring devices 4A to 4C. The number of times of measuring the flow rate of the fluid in the period P1 is different. Specifically, the flow rate measuring device 4A measures the flow rate for a total of 4 times within the first period P1, the flow rate measuring device 4B measures the flow rate for a total of 5 times, and the flow rate measuring device 4C measures the flow rate for a total of 6 times. It is configured to measure.

  Even the flow measurement device 100 of the present modification configured as described above has the same effects as the flow measurement device 100 according to the third embodiment.

  In addition, in the flow measuring device 100 of this modification, although the timing which measures the flow volume of the first fluid in the 1st period P1 of each flow measuring device 4A-4C is the same, it employ | adopted, but it is not limited to this. As in the flow rate measuring device 100 according to the first embodiment, a mode in which the timing of measuring the first fluid flow rate in the first period P1 of each of the flow rate measuring devices 4A to 4C may be adopted.

  Further, in this modification, each of the flow rate measuring devices 4A to 4C adopts a mode in which the flow rate measurement intervals are set to predetermined fixed values (predetermined interval ISa, predetermined interval ISb, and predetermined interval ISc). However, the present invention is not limited to this. If each of the flow rate measuring devices 4A to 4C can change the timing for measuring the flow rate of the fluid in the first period P1, each of the flow rate measuring devices 4A to 4C may adopt a form in which the flow rate measurement intervals are different. Good. That is, for example, the flow rate measuring device 4A may measure the flow rate so that the interval between tA1 and tA2 is different from the interval between tA2 and tA3 (length of time). .

  As described above, the first embodiment shows an example in which the measurement timings to be executed first in the same first period P1 in each of the flow rate measuring devices 4A to 4C coincides, and in the second embodiment, the flow rate measuring devices 4A to 4C. The example in which the measurement intervals in the second periods PA to PC are different from each other is shown. In the third embodiment, the example in which the second periods PA to PC are different from each other is shown in each of the flow rate measuring devices 4A to 4C. And in the said modification, although the example which combined Embodiment 2, 3 was shown generally, it is a case where any aspect which combined 2 or more of Embodiment 1-3 is employ | adopted. In addition, it is possible to realize the measurement of the total flow rate while reducing the influence of the periodic fluctuation of the flow rate.

  In the above-described embodiment, the flow measurement device 100 that measures the gas usage amount has been described as an example, but the measurement target is not limited to gas, and may be a fluid.

  From the foregoing description, many modifications and other embodiments of the present invention are obvious to one skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

  The flow rate measuring device of the present invention can reduce the influence of periodic fluctuations in the flow rate, and as a result, can improve the measurement accuracy of the total flow rate of the fluid, and is therefore useful in the field of flow meters. is there.

DESCRIPTION OF SYMBOLS 1 Inflow port 2 Outlet port 3A Flow path 3B Flow path 3C Flow path 4A Flow rate measuring device 4B Flow rate measuring device 4C Flow rate measuring device 5 Main controller (flow rate calculator)
DESCRIPTION OF SYMBOLS 6 Inlet buffer part 7 Blocking mechanism 8 Outlet buffer part 11 Upstream ultrasonic sensor 12 Downstream ultrasonic sensor 13 Sub controller 13A Calculator 13B Memory 14 Battery 15 Display 100 Flow rate measuring device

Claims (2)

A plurality of flow paths provided between the inlet and the outlet;
A flow rate measuring device that is provided in each of the flow paths and measures the flow rate of fluid flowing through the flow path;
A flow rate calculator for calculating a total flow rate of fluid flowing between the inlet and the outlet from the flow rate measured by the flow rate measuring device;
Each of the flow rate measuring devices performs the fluid flow rate measurement a predetermined number of times within a first period in which start times coincide with each other. Configured to calculate the flow rate,
Two or more flow rate measuring instruments are
(A) Timing for executing the first measurement of the flow rate of the fluid within the first period;
(B) an interval for measuring the flow rate of the fluid within the first period;
(C) the length of the second period, which is a period in which the measurement of the flow rate of the fluid within the first period is executed a predetermined number of times;
Among them, at least one of the plurality of flow paths is configured to be different from each other, and the interval between the measurement execution timings in the plurality of flow paths is set to a time at which measurement accuracy can be obtained according to the period of the pulsation when the pulsation occurs. The flow measurement device. The said flow measuring device has a pair of ultrasonic transducer | vibrator, It is comprised so that the flow velocity of the fluid which flows through the said fluid flow path may be measured using an ultrasonic signal. Flow measurement device.

Images