JP2000009505A - Fluidic flow meter - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a fluidic flow meter capable of detecting an abnormality of a flow rate measuring means and recovering quickly by appropriate measures. SOLUTION: A fluidic flow meter 1 equipped with a dedicated flow rate sensor 6 for measuring a small flow rate is provided with a non-volatile storage means 82 for recording measurement data and the like, and
A warning generation circuit 73 of the arithmetic processing unit 7 that performs abnormality detection based on the sensor output is provided, and when there is an abnormality in the outputs of the fluidic element 5 and the flow velocity sensor 6, the number of occurrences of the abnormality is counted for each abnormality mode. And the non-volatile storage means 82
When the same number of occurrences of the abnormality are repeated a predetermined number of times, the abnormality warning means 83 is activated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring a flow rate by a fluidic element when a flow rate of a fluid to be measured is a medium flow rate or a large flow rate, and by measuring a flow rate by a flow rate sensor when the flow rate is a small flow rate. Fluidic flowmeters that achieve high-precision flow rate measurement in a wide range of flow rates.For details, see Fluidic flowmeters that have been improved to realize quick recovery in the event of an abnormality in these fluidic elements and flow rate sensors. About.

[0002]

2. Description of the Related Art In recent years, fluidic flow meters have been receiving attention as flow meters used in electronic gas meters and the like. This fluidic flow meter detects an appropriate physical quantity that changes according to the flow velocity of the fluid flowing in the flow path using an electronic sensor provided in the flow path, and detects the flow based on a detection signal of the electronic sensor. It is classified as a guess-type flow meter that intermittently measures the flow velocity in the road and estimates the integrated flow rate, and uses a fluidic element as an electronic sensor. Fluidic element is to detect the fluid vibration as a physical quantity that changes according to the flow velocity of the fluid flowing in the flow path, specifically, the fluid to be measured flowing in the element causes fluid vibration due to a vortex street, It is configured to detect the fluid vibration, convert it to an electric signal such as a pulse signal and output it.

[0003] Fluid vibrations are less likely to occur when the flow velocity is low, and it is difficult to understand the correlation with the flow velocity. Accordingly, a fluidic flow meter using a fluidic element can generally perform high-accuracy measurement at a large flow rate or a medium flow rate at which the flow rate of the fluid to be measured increases, but a small flow rate at which the flow rate of the fluid to be measured decreases. There is a problem that the measurement error becomes large at the time of flow. Therefore, there has been proposed a fluidic flow meter in which the flow rate is measured by a fluidic element when the flow rate is equal to or more than a certain flow rate, and the flow rate is measured by another flow rate sensor when the flow rate is equal to or less than the certain flow rate. (See JP-A-1-58118).

As a flow rate sensor for a small flow rate, for example, a pair of temperature detecting elements detects a temperature difference of a measured fluid between two positions sandwiching a heater in a flow path as a physical quantity indicating a flow rate of the measured fluid. There is known a configuration in which a pulse signal is output as a pulse signal.

[0005]

However, a fluidic flow meter having such a configuration in which a dedicated flow rate sensor is additionally provided for measuring a small flow rate can realize highly accurate measurement over a wide flow rate range. On the other hand, as the number of mounted electronic sensors increases, the operation of the electronic sensors due to failure of the electronic sensors themselves or disconnection of the lead wires or poor contact that sends the output of the electronic sensors to the processing unit, etc. A failure or the like is likely to occur, and sufficient consideration is required for an operation failure or the like of the electronic sensor. For example, if a failure occurs in the electronic sensor for measuring the small flow rate and the flow measurement is continued only with the electronic sensor for measuring the large and medium flow rate that is operating normally, the measurement error will increase. Become
There is a risk of inconvenience. Therefore, until now, as a fluidic flow meter of a configuration additionally equipped with a dedicated flow rate sensor for measurement of small flow rate, the abnormality of each electronic sensor is determined based on the output signals of the flow rate sensor and the fluidic element, A technique has been proposed in which an abnormality determination circuit is provided for generating an alarm signal indicating an instrument failure when any one of the electronic sensors becomes abnormal (see Japanese Patent Application Laid-Open No. 4-47224).

However, it is not sufficient to provide an abnormality determination circuit that outputs an alarm signal when an abnormality occurs in the electronic sensor. In the case of the above-described conventional abnormality determination circuit, since the location of the abnormality and the frequency of occurrence of the abnormality are not known, even if the occurrence of a failure in the fluidic flow meter is detected by the alarm signal, in order to recover the failure, first, A specialized engineer or the like must perform various tests on site to identify the abnormal location, and a problem arises in that the recovery work is delayed due to the work of identifying the abnormal location.

The present invention has been made in view of the above circumstances, and is a fluidic flow meter having a configuration in which a dedicated flow rate sensor is additionally provided for measuring a small flow rate, wherein the electronic sensor used for the flow rate measurement is provided. If an abnormality occurs in any of the above, the occurrence of the abnormality can be detected promptly, and failure information such as the location and frequency of occurrence of the abnormality is recorded and stored in the non-volatile storage means. It is an object of the present invention to provide a fluidic flow meter capable of easily and quickly specifying the flow rate and realizing quick recovery by appropriate measures.

[0008]

According to the present invention, there is provided a fluid flow meter for detecting a fluid by measuring a fluid vibration in a flow path as a physical quantity indicating a flow velocity of a fluid to be measured. An element, a flow rate sensor that detects by measuring a temperature difference between two positions in the flow path as a physical quantity indicating the flow rate of the fluid to be measured, and an abnormality of these flow rate measurement means based on outputs of the fluidic element and the flow rate sensor. In a fluidic flow meter including an arithmetic processing unit for determining and an abnormality warning unit for notifying the abnormality of the flow velocity measuring unit by the arithmetic processing unit, a nonvolatile storage unit for recording measurement data of the flow velocity measuring unit is provided. At the same time, the arithmetic processing unit determines whether the flow rate of the fluid to be measured is large, medium, or small based on the output of the flow velocity measuring means, At a medium flow rate, the flow rate is calculated based on the output of the fluidic element. At a small flow rate, the flow rate is calculated based on the output of the flow rate sensor. Is detected, and if there is an abnormality, the number of occurrences of the abnormality is counted for each mode of abnormality and recorded in the nonvolatile storage means. When the same number of occurrences of the abnormality is repeated a predetermined number of times, Activating the abnormality warning means.

According to the above configuration, if an abnormality occurs in any of the electronic sensors used for the flow rate measurement,
The occurrence of the abnormality is immediately determined by the arithmetic processing unit. The arithmetic processing unit records failure information such as the location and frequency of occurrence of the abnormality in the non-volatile storage unit, and activates the abnormality warning unit when the same number of occurrences of the abnormality is repeated a predetermined number of times. Notify the occurrence of Therefore, occurrence of an abnormality in the electronic sensor or the like can be promptly detected. Further, since failure information such as the location and frequency of occurrence of an abnormality is recorded in the non-volatile storage means, at the time of a recovery operation, by examining the information in the non-volatile storage means, it is possible to easily and quickly specify the abnormal location. .

[0010] When communication means for transmitting data to a monitoring device such as a facility performing maintenance work of the flow meter is provided as the abnormality warning means, the arithmetic processing unit causes the communication means to generate and detect an abnormality. Can be notified to a predetermined monitoring device. In this way, the technician performing the recovery work can immediately confirm the location of the occurrence of the abnormality from the abnormality notification information.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a fluidic flow meter according to the present invention will be described below in detail with reference to the drawings. 1 to 3 show an embodiment of a fluidic flow meter according to the present invention. FIG. 1 is a block diagram showing a schematic configuration of a fluidic flow meter according to the present invention, and FIGS. 2 and 3 are diagrams. 3 is a flowchart showing a process of the arithmetic processing unit in the fluidic flow meter shown in FIG.

The fluidic flow meter 1 is a fluidic flow meter as a flow rate measuring means provided in the flow path 3 with an appropriate physical quantity which varies in accordance with the flow rate of the fluid to be measured flowing in the flow path 3 in the direction of the arrow (a). A guessing equation for detecting intermittently at regular intervals (for example, every 6 seconds) by the element 5 and the flow rate sensor 6 and measuring the flow rate based on the output signals from these flow rate measuring means 5 and 6 to estimate the integrated flow rate. It is a flow meter used for electronic gas meters and the like.

The fluidic flow meter 1 calculates the flow rate of the fluid to be measured based on the outputs from the fluidic element 5 and the flow rate sensor 6 in addition to the fluidic element 5 and the flow rate sensor 6 described above. Device 7, a flow rate display means 81 connected to the arithmetic processing device 7 for displaying the flow rate calculated by the arithmetic processing device 7, and a non-volatile storage means 82 connected to the arithmetic processing device 7 for recording data and the like.
And an abnormality warning means 83 for notifying the occurrence of an abnormality by turning on a lamp or an alarm, and a communication means 84 for transmitting the processing result and the like of the arithmetic processing unit 7 to a monitoring apparatus such as a facility for maintenance work. Is done.

Although not shown, the fluidic element 5 generates fluid vibration due to a vortex street in a fluid to be measured flowing through the element, and detects the fluid vibration as a physical quantity that changes according to the flow velocity of the fluid. Thus, it is configured to convert the fluid vibration into an electric pulse signal and output it.

The flow rate sensor 6 is provided at a nozzle portion on the flow path 3 through which the fluid to be measured flows into the fluidic element 5, and includes a heater 61 for heating the fluid to be measured, and an upstream side and a rear side of the heater 61. A pair of temperature detecting elements 62 and 63 for detecting the temperature of the fluid to be measured on the flow side;
The temperature difference of the fluid to be measured between the two positions sandwiching 1 is detected by the temperature detecting elements 62 and 63 and output as a pulse signal.

The fluidic element 5 is used for measurement at medium and large flow rates where the flow rate is 130 l / h or more. As shown in Table 1 below, when the flow rate is 130 l / h or more, the fluid element 5 is normal. Then, a pulse signal of 1 to 150 Hz is output. The flow rate sensor 6 has a flow rate of 130 l / h.
As shown in Table 1 below, when the flow rate is less than 130 l / h, if the flow rate is normal, the temperature difference between the pair of temperature detection elements 62 and 63 is 700 pulses. Output less than pulse signal.

[0017]

[Table 1]

When the output of the fluidic element 5 indicates a value at a small flow rate, the output from the flow velocity sensor 6 indicates a value at a medium or large flow rate, or conversely, the output of the fluidic element 5 indicates If the output from the flow rate sensor 6 indicates a value at a small flow rate while indicating a value at a medium / large flow rate, either the fluidic element 5 or the flow rate sensor 6 is abnormal.

In the flow rate sensor 6, if the temperature detecting elements 62 and 63 are normal, the number of output pulses P _{1 of} the first temperature detecting element 62 located on the upstream side and the second pulse number on the downstream side. output pulse number P ₂ of the temperature detection element 63 is a value as shown in the following Table 2.

[0020]

[Table 2]

When the output values from these temperature detecting elements 62 and 63 deviate from the ranges shown in Table 2, it means that the flow rate sensor 6 is abnormal.

In the case of this embodiment, an EEPROM (electrically erasable read-only memory) is used as the non-volatile storage means 82. The communication unit 84 performs predetermined data transmission via a telephone line, a dedicated line, or wireless communication.

The arithmetic processing unit 7 includes a fluidic element 5
And a flow rate determining circuit 71 for determining whether the flow rate of the fluid to be measured is large, medium, or small based on the output of the flow rate sensor 6. The flow rate is calculated based on the output, and when the flow rate is small, the flow rate is calculated based on the output of the flow velocity sensor 6, and the calculated flow rate is displayed on the flow rate display means 81.
The abnormality of these flow rate measuring means 5 and 6 is detected from the output means of the display means control circuit 72 and the outputs of the fluidic element 5 and the flow rate sensor 6, and if there is an abnormality in the output of the fluidic element 5 and the flow rate sensor 6 The number of times of occurrence of abnormality is counted for each mode of abnormality and recorded in the non-volatile storage means 82. When the same number of occurrences of abnormality is repeated a predetermined number of times (10 times in this embodiment), Abnormality warning means 83
And a warning generating circuit 73 for operating the alarm.

Further, in the case of the present embodiment, the alarm generation circuit 7
3 is to activate the abnormality warning means 83 when the same abnormality occurrence number is repeated a predetermined number of times, and at the same time, to notify the occurrence of the abnormality and the state of the abnormality to a predetermined monitoring device by the communication means 84. Is formed.

The arithmetic processing unit 7 includes the above-described flow rate determination circuit 7
1. The display means control circuit 72 and the warning generation circuit 73
As shown in FIGS. 2 and 3, the flow rate calculation processing and the warning generation processing are performed at regular time intervals. That is, first, it is determined whether or not the output value of the fluidic element 5 is less than the lower limit (step 101). In step 101, the fluidic element 5
When the output value is determined to be equal to or less than the lower limit value, there is no output of the fluidic element 5, or the output is unstable, and there is a high probability that the flow rate is small. Therefore, next, the outputs P ₁ and P ₂ of the temperature detecting elements 62 and 63 of the flow velocity sensor 6 are read (step 102). Next, it is determined whether or not the outputs P ₁ and P _{2 of} these temperature detecting elements 62 and 63 are appropriate, and the value of the output difference (P ₁ −P ₂ ) of the temperature detecting elements 62 and 63 is determined in step 101. Are determined in order (steps 103 to 10).
5) If the output is determined to be appropriate in each of these steps 103 to 105, a prescribed flow rate calculation process for a small flow rate is performed based on the output of the flow rate sensor 6, and a flow rate display process and the like are performed. Then (step 106), the process returns to step 101.

[0026] In step 103, when the output P ₁ of the temperature detecting element 62 which is located upstream of the flow path 3 is determined to improper is to identify the temperature detecting element 62 as a break occurrence portion, The warning generation process is started (step 201), and the number CN of occurrences of abnormality of the temperature detection element 62
By adding +1 to T _1, · updated in the nonvolatile memory means 82
It is recorded (step 202), and if the same number of occurrences of the abnormality has reached 10 (step 203), a warning process for activating the abnormality warning unit 83 and the mode of occurrence and abnormality of the abnormality by the communication unit 84 ( A process of notifying data such as an abnormality occurrence location) to a predetermined monitoring device is performed (step 204), and the process returns to step 101. In step 203,
If the number of occurrences of the abnormality is less than 10, the process immediately returns to step 101 without performing the warning process.

If it is determined in step 104 that the output P ₂ of the temperature detecting element 63 located downstream of the flow path 3 is inappropriate, the temperature detecting element 63 is specified as an abnormality generating section, The warning generation process is started (step 301), and the number CN of occurrences of abnormality of the temperature detection element 63
To T ₂ by adding +1, and updated in the nonvolatile memory means 82
It is recorded (step 302), and then, if the same number of occurrences of abnormality has reached 10 (step 303), a warning process for activating the abnormality warning unit 83, and a mode of occurrence and abnormality of abnormality by the communication unit 84 ( A process for notifying data such as an abnormality occurrence location) to a predetermined monitoring device is performed (step 304), and the process returns to step 101. In step 303,
If the number of occurrences of the abnormality is less than 10, the process immediately returns to step 101 without performing the warning process.

In step 105, the temperature detecting element 6
If it is determined that the output difference between 2, 63 is 700 pulses or more, it is highly probable that the flow rate is a medium / large flow rate, so it is determined that there is an abnormality in the output of the fluidic element 5 and the fluidic element 5 identify and as abnormal unit starts warning generation process (step 401), the abnormality occurrence count CNT ₃ of fluidic element 5 by adding +1, updated and recorded in a nonvolatile memory means 82 (step 402 Next, if the number of occurrences of the same abnormality has reached 10 times (step 403), a warning process for activating the abnormality warning means 83, and the occurrence of the abnormality and the mode of the abnormality (the location of the abnormality) by the communication means 84, etc. Is performed to the predetermined monitoring device (step 404), and the process returns to step 101. If the number of times of occurrence of the abnormality is less than 10 in step 403, the process immediately returns to step 101 without performing the warning process.

In step 101, the fluidic element 5
If the output value is equal to or larger than the lower limit, it is determined whether the output value of the fluidic element 5 is equal to or smaller than the upper limit (step 501). When it is determined in step 501 that the output value of the fluidic element 5 is equal to or less than the upper limit value, it is highly probable that the output of the fluidic element 5 is within an appropriate range and the flow rate is a medium or large flow rate. Therefore, next, the outputs P ₁ and P ₂ of the temperature detecting elements 62 and 63 of the flow rate sensor 6 are read (step 502). Next, it is determined whether or not the outputs P ₁ and P _{2 of} these temperature detecting elements 62 and 63 are appropriate, and the difference between the outputs of the temperature detecting elements 62 and 63 (P
_It is sequentially determined whether or not the value of ( _1- P ₂ ) matches the determination of step 501 (steps 503 to 505). If the output is determined to be appropriate in each of these steps 503 to 505, the screen is cleared. The output of the dick element 5 is read (step 506), and based on the output value of the fluidic element 5, a prescribed flow rate calculation process for medium / large flow rate is performed, and a flow rate display process and the like are performed (step 507). ), And return to step 101.

Steps 503 to 505 correspond to the flow rate sensor 6
This is performed in order to confirm whether or not each of the temperature detecting elements 62 and 63 has an abnormality, and to confirm the reliability of the determination in step 501. In step 503, the output P _{1 of the} temperature detection element 62 located on the upstream side of the flow path 3
Is judged to be inappropriate, the temperature detecting element 6
2 is specified as an abnormality generating unit, and the above-described step 20 is performed.
The process proceeds to 1 to start the warning generation process. Similarly, in step 504, when the output P ₂ of the temperature detection element 63 that is located downstream of the flow path 3 is determined to improper it is to identify the temperature detecting element 62 as a break occurrence portion, The process proceeds to step 301 to start the warning generation process. If it is determined in step 505 that the output of the flow path 3 is less than 700 pulses, it is determined that the fluidic element 5 is abnormal. The process proceeds to step 401 to start the warning generation process.

In step 501, the fluidic element 5
When the output of the is judged to exceed the upper limit value, immediately it determines that the abnormality of the fluidic device 5 starts the warning generation process (step 601), the abnormality occurrence count CNT ₄ of fluidic elements 5 +1 is added and updated / recorded in the non-volatile storage means 82 (step 602). Then, if the same abnormality occurrence number has reached 10 (step 603), the alarm processing for activating the abnormality alarm means 83 Then, the communication unit 84 performs a process of notifying the data of the occurrence of the abnormality and the mode of the abnormality (the location of the abnormality) to a predetermined monitoring device (step 604), and returns to step 101. If the number of times of occurrence of the abnormality is less than 10 in step 603, the process immediately returns to step 101 without performing the warning process.

As is clear from the above description, in the fluidic flow meter 1 of the present embodiment, an abnormality occurs in one of the flow velocity measuring means (fluidic element 5, flow velocity sensor 6) used for flow measurement. Then, the abnormality is immediately detected by the warning generation circuit 73 provided in the arithmetic processing unit 7. Then, the warning generation circuit 73 records failure information such as the location and frequency of occurrence of the abnormality in the nonvolatile storage unit 82, and activates the abnormality warning unit 83 when the same number of occurrences of the abnormality is repeated a predetermined number of times. To report the occurrence of an abnormality. Therefore, occurrence of an abnormality in the electronic sensor or the like can be promptly detected. Further, since failure information such as the location and frequency of occurrence of an abnormality is recorded in the non-volatile storage means 82 and remains there, by examining the non-volatile storage means 82 at the time of recovery work, it is easy and quick to specify the abnormal location. Can be done.
Therefore, it is possible to realize quick recovery by appropriate measures without the trouble of specifying the abnormal portion.

In the case of the present embodiment, the alarm generation circuit 73 is configured to notify the occurrence of an abnormality and the mode of the abnormality to a predetermined monitoring device by the communication means 84.
The technician performing the recovery work can immediately recognize the abnormal location from the abnormality notification information, and can more appropriately perform the appropriate recovery work.

The specific configurations of the fluidic element 5 and the flow rate sensor 6 described above are not limited to the present embodiment, and the design can be changed as appropriate without departing from the spirit of the present invention.

[0035]

According to the fluidic flow meter of the present invention, if an abnormality occurs in any of the electronic sensors used for measuring the flow rate, the occurrence of the abnormality is determined by a warning generation circuit provided in the arithmetic processing unit. Is immediately detected by And
The alarm generation circuit records failure information such as the location and frequency of occurrence of the abnormality in the nonvolatile storage means, and activates the abnormality warning means when the same number of occurrences of the abnormality is repeated a predetermined number of times. Notify the occurrence of Therefore, occurrence of an abnormality in the electronic sensor or the like can be promptly detected. In addition, since failure information such as the location and frequency of occurrence of an abnormality is recorded in the non-volatile storage unit and remains, during recovery work, the information remaining in the non-volatile storage unit is examined to identify the abnormal location. Can be done easily and quickly. Therefore, it is possible to realize quick recovery by appropriate measures without the trouble of specifying the abnormal portion.

As an abnormality warning means, a communication means for transmitting data to a monitoring device such as a facility for maintenance work of the flow meter is provided, and a warning generation circuit is provided by the communication means.
When the occurrence of the abnormality and the mode of the abnormality are notified to a predetermined monitoring device, the engineer performing the recovery work can immediately identify the abnormal portion from the abnormality notification information, and more quickly,
Appropriate recovery work can be performed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of an embodiment of a fluidic flow meter according to the present invention.

FIG. 2 is a flowchart showing a process of the fluidic flow meter of FIG.

FIG. 3 is a flowchart showing a process of the fluidic flow meter of FIG. 1;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 fluidic flow meter 3 flow path 5 fluidic element (flow rate measuring means) 6 flow rate sensor (flow rate measuring means) 7 arithmetic processing unit 61 heater 71 flow rate determining circuit 72 display means control circuit 73 warning generating circuit 81 flow rate displaying means 82 non-volatile Storage means 83 abnormality warning means 84 communication means

Claims (2)

[Claims] 1. A fluidic element which is detected by measuring a fluid vibration in a flow path as a physical quantity indicating a flow rate of a fluid to be measured, and a temperature between two positions in the flow path as a physical quantity indicating a flow rate of the fluid to be measured. A flow rate sensor that detects the difference by measuring the difference, an arithmetic processing unit that determines the abnormality of the flow rate measuring means from the outputs of the fluidic element and the flow rate sensor, and notifies the abnormality of the flow rate measuring means by the arithmetic processing unit. A fluid flow meter comprising an abnormality warning unit, wherein a non-volatile storage unit for recording measurement data of the flow velocity measurement unit is provided, and the arithmetic processing unit is configured to calculate a flow rate of the fluid to be measured based on an output of the flow velocity measurement unit. The flow rate is determined based on the output of the fluidic element when the flow rate is large, medium, or small. Sometimes, the flow rate is calculated based on the output of the flow velocity sensor, and the abnormality of the fluidic element and the flow velocity sensor is detected from the output of the flow velocity measuring means. The number of occurrences is counted and recorded in the nonvolatile storage means,
A fluidic flowmeter characterized in that the abnormality warning means is activated when the same number of occurrences of an abnormality is repeated a predetermined number of times. 2. A communication device for transmitting data to a monitoring device such as a facility performing maintenance work of a flow meter as the abnormality warning device, wherein the arithmetic processing device is configured to detect occurrence and abnormality of the abnormality by the communication device. The fluidic flowmeter according to claim 1, wherein the mode is notified to a predetermined monitoring device.