JPH10292900A - Flow rate measuring device and pipe volume measuring method - Google Patents

Abstract

(57) [Summary] [Problem] To automatically detect a location where a supply pressure abnormality occurs. SOLUTION: A passing flow rate measuring means 6 for measuring a passing flow rate of a fluid passing through a fluid passage 1, a pressure measuring means 10, 11 for measuring a pressure of a fluid passing through the fluid passage 1, and a means for opening and closing the fluid passage. 4 is provided. Thus, the flow rate value measured by the passing flow rate measuring means 6 and the pressure measuring means 1
From the pressure values measured at 0 and 11, it can be determined whether the location of the supply pressure abnormality is upstream or downstream of the fluid passage opening / closing means 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow rate measuring device for automatically detecting an abnormal supply pressure of a fluid and a method for measuring a pipe capacity.

[0002]

2. Description of the Related Art A conventional flow measuring device of this type is generally described in Japanese Patent Application Laid-Open No. HEI 8-189872 (see FIG. 7). That is, a fluid passage opening and closing means 4 for opening and closing the fluid passage from the upstream side 2 to the downstream side 3 in the fluid passage 1, a pressure measuring means 5 for measuring the pressure of the fluid, a passing flow rate for measuring the passing flow rate of the fluid Measuring means 6 are sequentially arranged, and a fluid flow meter 8 is configured in which the control unit 7 controls the fluid passage opening / closing means 4 for opening / closing the fluid passage based on the measurement results of the fluid pressure and the flow rate of the fluid. Reference numeral 9 denotes an informing means for displaying a pressure measurement result, a passing flow rate measurement result, and the like. In the fluid flow meter 8 having such a configuration, when the pressure drop of the fluid pressure becomes equal to or less than the predetermined value based on the output signal of the pressure measuring means 5, the control unit 7 determines that there is an abnormality, The fluid supply opening / closing means 4 was operated to automatically stop the supply of the fluid.

[0003]

However, in the above-described conventional configuration, when an abnormality such as a pressure drop occurs,
Since the pressure measuring means 5 is configured on the downstream side of the fluid passage opening / closing means 4, it is not possible to determine whether an abnormality such as a pressure drop is upstream or downstream of the fluid passage opening / closing means 4.
Further, since the pressure states of the fluids on the upstream side and the downstream side cannot be measured at the same time, the closed fluid passage opening / closing means 4 cannot be automatically opened after an abnormality such as a pressure drop.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a fluid flow measuring device comprising a first pressure measuring means for measuring the pressure of a fluid from upstream to downstream of a fluid passage. Fluid passage opening / closing means for opening / closing the fluid passage, second pressure measuring means for measuring the pressure of the fluid, and passing flow rate measuring means for measuring the passing flow rate of the fluid.
And the state of supply of the fluid is determined from the measurement results of the second pressure measuring means and the flow rate measuring means.

According to the present invention, even if an abnormality such as a pressure drop occurs, the pressure measuring means for measuring the pressure of the fluid is provided on both the upstream and downstream sides of the fluid passage opening / closing means. Even if the fluid passage is closed by operating the passage opening / closing means, it is possible to measure the pressure of the fluid on both the upstream side and the downstream side of the fluid passage opening / closing means, and whether an abnormality such as a pressure drop occurs on the upstream side. , Or whether it occurred on the downstream side. Also, even if the fluid passage opening / closing means is operated due to a pressure drop abnormality and the fluid passage is closed, the pressure of the fluid on the upstream side or the downstream side can be simultaneously measured, so after confirming safety, The closed fluid passage opening / closing means can be automatically opened and the supply of fluid can be started automatically.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A fluid flow measuring device according to the present invention comprises: first pressure measuring means for measuring the pressure of a fluid from upstream to downstream of a fluid passage; fluid passage opening / closing means for opening / closing the fluid passage; A second pressure measuring means for measuring the pressure of the fluid, and a passing flow rate measuring means for measuring the passing flow rate of the fluid, and supply of the fluid from the measurement results of the first and second pressure measuring means and the flow rate measuring means. A control means for judging a state and operating the fluid passage opening / closing means, and a notifying means for notifying the judgment result are provided. Thereby, the fluid passage opening / closing means is operated due to a pressure drop abnormality, etc.
Even if the fluid passage is closed, the pressure of the fluid on the upstream side and the pressure on the downstream side can be simultaneously measured, so that it is possible to determine whether an abnormality such as a pressure drop has occurred on the upstream side or the downstream side. . Further, since the supply state of the fluid on the upstream side or the downstream side can be confirmed, the closed fluid passage opening / closing means can be automatically opened after confirming the safety.

[0007] An upstream pressure introduction hole for measuring the pressure of the fluid from upstream to downstream of the fluid passage, a fluid passage opening / closing means for opening and closing the fluid passage, and a downstream pressure for measuring the pressure of the fluid. Inlet holes, passing flow rate measuring means for measuring the passing flow rate of the fluid are sequentially configured, and pressure measuring means for measuring the pressure of the fluid via a switching valve is connected to the upstream pressure introducing hole and the downstream pressure introducing hole. A configuration comprising: control means for determining the supply state of the fluid from the measurement result of the pressure measurement means and the measurement result of the flow rate measurement means, operating the fluid passage opening / closing means, and a notification means for reporting the determination result. did. Thus, even if the fluid passage opening / closing means is operated due to a pressure drop abnormality or the like and the fluid passage is closed, the pressures of the upstream and downstream fluids can be measured almost simultaneously by operating the switching valve. Therefore, it is possible to determine whether an abnormality such as a pressure drop has occurred on the upstream side or the downstream side. Further, since the supply state of the fluid on the upstream side or the downstream side can be confirmed, the fluid can be gradually supplied to the downstream side through the upstream side pressure introduction hole and the downstream side pressure introduction hole, and the downstream side The closed fluid passage opening / closing means can be automatically opened while confirming the increase in the pressure.

[0008] Further, the switching valve of the fluid flow rate measuring device,
There are three connection ports, and any two connection ports can be selected. Therefore, when the fluid passage opening / closing means operates and the fluid passage is closed, it can be used as a bypass passage for supplying fluid. Further, when the fluid pressure measuring means fails, the pressure measuring means can be replaced with a normal one without closing the fluid passage.

The switching valve has four connection ports, and is constituted by a switching valve capable of selecting any three connection ports.
For this reason, when the fluid passage opening / closing means is operated and the fluid passage is closed, it can be used as a bypass passage for supplying fluid, and further, in the state of supply of fluid to the downstream side,
The pressure change on the downstream side can also be measured. Further, when the fluid pressure measuring means fails, the pressure measuring means can be replaced with a normal one without closing the fluid passage.

The method for measuring the volume of a downstream fluid passage according to the present invention includes an upstream pressure introduction hole for measuring the pressure of the fluid from upstream to downstream of the fluid passage, a fluid passage opening / closing means for opening / closing the fluid passage, A downstream pressure introducing hole for measuring the pressure of the fluid, a passing flow rate measuring means for measuring the passing flow rate of the fluid are sequentially constituted, and the fluid is supplied to the upstream pressure introducing hole and the downstream pressure introducing hole via a switching valve. Control means for connecting a pressure measuring means for measuring the pressure of the fluid, judging a supply state of the fluid from a measurement result of the pressure measuring means and a measurement result of the flow rate measuring means, and operating the fluid passage opening / closing means; And a notifying means for notifying the result, by closing the fluid passage opening and closing means, and by sequentially selecting the connection ports of the switching valve, the upstream pressure or the downstream pressure. Or by measuring the flow rate of the fluid supplied to the downstream side through the upstream pressure introduction hole and the downstream pressure introducing hole, and measures the volume of the downstream side fluid passage. Therefore, the downstream pipe capacity and the like can be displayed, and for example, it is possible to obtain a guide for determining whether or not the pipe diameter is appropriate.

Further, the fluid flow rate measuring device of the present invention comprises: a first fluid passage opening / closing means for opening / closing the fluid passage from upstream to downstream of the fluid passage; a pressure measuring means for measuring the pressure of the fluid; A second fluid passage opening / closing means for opening and closing the passage, and a passing flow rate measuring means for measuring a passing flow rate of the fluid are sequentially constituted, and a supply state of the fluid is determined from a measurement result of the pressure measuring means and a measurement result of the flow rate measuring means. Then, the control device is configured to include control means for operating the fluid passage opening / closing means, and notification means for notifying the determination result.
Therefore, even if the fluid passage opening / closing means is operated due to a pressure drop abnormality and the fluid passage is closed, the pressure of the fluid on the upstream side and the downstream side is appropriately opened / closed by the first and second fluid passage opening / closing means. Can be measured. Therefore,
It is possible to determine whether an abnormality such as a pressure drop has occurred on the upstream side or the downstream side. Similarly, since the supply state of the fluid on the upstream side or the downstream side can be confirmed, the closed fluid passage opening / closing means can be automatically opened after confirming the safety.

Further, a method of measuring the volume of the downstream fluid passage is as follows.
A first fluid passage opening / closing means for opening / closing the fluid passage from upstream to a downstream of the fluid passage, a pressure measurement means for measuring a pressure of the fluid, a second fluid passage opening / closing means for opening / closing the fluid passage, The flow rate measuring means for measuring the passing flow rate is sequentially configured, and the supply state of the fluid is determined from the measurement result of the pressure measuring means and the measurement result of the flow rate measuring means,
A closed space formed by a first fluid passage opening / closing fluid and a second fluid passage opening / closing fluid, which comprises control means for operating the fluid passage opening / closing means and notifying means for notifying the determination result; The volume of the downstream fluid passage is measured from the pressure and the pressure change when the second fluid passage opening / closing means fluid is released, and the volume of the downstream fluid passage is measured. Therefore, the downstream pipe capacity and the like can be displayed, and for example, it is possible to obtain a guide for determining whether or not the pipe diameter is appropriate.

An embodiment of the present invention will be described below with reference to the drawings. (Embodiment 1) FIG. 1 shows a fluid flow measuring device according to Embodiment 1 of the present invention. From an upstream side 2 to a downstream side 3 of the fluid passage 1, an on-off valve 4 as a fluid passage opening / closing means for opening / closing the fluid passage 1 and a flow meter 6 as a passing flow rate measuring means for measuring a passing flow rate of the fluid are sequentially configured. Further, first and second pressure sensors as first and second pressure measuring means 10 and 11 for detecting the pressure of the fluid on the upstream side and the downstream side of the on-off valve 4 are provided. Further, the measurement result of the flow meter 6 and
The control unit 7 controls the on-off valve 4 based on the detection results of the first and second pressure sensors. Reference numeral 9 denotes a liquid crystal display as a leaving means for displaying a flow measurement result, an output result of the control unit 7, and the like. Reference numeral 8 denotes a fluid flow meter configured as described above. In addition, the flowmeter 6 is 3-6000 [L / Hr].
Was used. Further, as the first and second pressure sensors, pressure sensors capable of measuring 0 to 500 [mmAq] were used.

In such a configuration, the pressure of the fluid is
When a pressure drop from 200 [mmAq] during normal operation to 100 [mmAq] or less occurs, the control unit 7 determines that the pressure has dropped based on the detection results of the first and second pressure sensors, and operates the on-off valve 4. , Shut off the fluid passage. After the operation of the on-off valve 4, the control unit 7 monitors the detection results of the first and second pressure sensors, so that it is possible to determine where the pressure drop abnormality has occurred. .

(1) If the result of detection by the first pressure sensor on the upstream side indicates an increase and the result of detection by the second pressure sensor on the downstream side indicates a decrease, an abnormality occurs on the downstream side from the on-off valve 4. It can be determined that it has been done.

(2) When the result of detection by the first pressure sensor on the upstream side indicates a decrease and the result of detection by the second pressure sensor on the downstream side also indicates a decrease, the upstream and downstream sides of the on-off valve 4 It can be determined that an abnormality has occurred in both cases.

(3) When the result of detection by the first pressure sensor on the upstream side indicates a drop and the result of detection by the second pressure sensor on the downstream side indicates no change, an abnormality is detected on the upstream side from the on-off valve 4. It can be determined that this has occurred.

As described above, the control unit 7 monitors the detection results of the first and second pressure sensors, so that an abnormal portion can be determined.

Further, for example, even if an external impact is applied to the flow meter 8 and the on-off valve 4 is operated by the reaction, the control unit 7 monitors the detection results of the upstream and downstream pressure sensors 10 and 11. By doing so, it can be determined that the on-off valve 4 has malfunctioned. That is, when a fluid is flowing (which can be determined from the measurement result of the flow meter 6), the pressure change hardly occurs in the pressure sensor 10 on the upstream side, but the pressure drop occurs in the pressure sensor 11 on the downstream side. Therefore, it can be determined that the on-off valve 4 is closed. At this time, when a difference occurs between the detection results of the upstream and downstream pressure sensors together with the flow of the fluid, the operation of the on-off valve 4 is confirmed, or the on-off valve 4 is operated so as to be opened. The abnormal operation of the on-off valve 4 can be eliminated.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described.
This will be described with reference to FIG. The fluid flow measuring device of the second embodiment has the same configuration as that of the first embodiment. However, the pressure sensor 5 as the fluid pressure detecting means is one element, a three-way switching valve 12 is provided, and the upstream pressure introduction hole and the downstream It was configured to be connected to the pressure passage inlet. FIG. 3 shows details of the three-way switching valve 12. FIG.
(A) shows a case where the pressure sensor 5 is connected to the upstream pressure introduction hole 13. In this case, the pressure sensor 5 can detect the pressure of the fluid on the upstream side of the on-off valve 4. FIG. 3B shows a case where the pressure sensor 5 is connected to the downstream pressure introduction hole 14. In this case, the pressure sensor 5 can detect the pressure of the fluid downstream of the on-off valve 4.
FIG. 3C shows a case where the pressure sensor 5 is not connected to either the upstream pressure introduction hole 13 or the downstream pressure introduction hole 14. In this case, the pressure sensor 5 cannot detect the pressure of the fluid flowing through the fluid passage 1. By operating the three-way switching valve 12 in this manner, one pressure sensor 5 can detect the pressure on the upstream side and the pressure on the downstream side of the on-off valve 4. Therefore, the same effect as in the first embodiment can be obtained. Further, in this case, when the pressure sensor 5 fails, the switching valve 12 is set to the state shown in FIG. 3C without closing the fluid passage, that is, while the fluid is flowing.
The pressure sensor 5 can be replaced. Further, when the on-off valve 4 is closed and a large differential pressure is applied between the upstream side and the downstream side, a large power is required to open the on-off valve 4. In such a case, by setting the switching valve 12 to the state shown in FIG. 3C, the upstream pressure introduction hole 13 and the downstream pressure introduction hole 14 can be used as the bypass passage of the fluid passage 1. As described above, the upper and lower sides of the on-off valve 4 are connected by the bypass passage, and the fluid flows, so that a large differential pressure applied to the upstream side and the downstream side of the on-off valve 4 can be eliminated. Therefore, the on-off valve 4 can be opened with small power. When the on-off valve 4 is operated by a battery or the like, a very large effect of power saving can be obtained. Further, in this case, it is possible to estimate the volume of the fluid passage after the on-off valve 4, the pipe capacity, and the like. That is, the upstream pressure introduction hole 1
The fluid is supplied from the upstream side to the downstream side by using a bypass passage composed of 3 and the downstream pressure introduction hole 14 for a certain period of time. Further, by detecting the pressures and pressure changes of the upstream and downstream fluids before and after that, it is possible to estimate the volume of the fluid passage after the on-off valve 4, the pipe capacity, and the like.

(Embodiment 3) Next, Embodiment 3 of the present invention will be described.
This will be described with reference to FIG. The fluid flow measuring device of the third embodiment has the same configuration as that of the second embodiment, except that the pressure sensor 5 as the fluid pressure detecting means is one element, and the four-way switching valve 15 is used instead of the three-way switching valve 12. FIG. 4 shows the relationship among the four-way switching valve 15, the upstream pressure introduction hole 13, the downstream pressure introduction hole 14, and the pressure sensor 5. FIG. 4A shows a case where the pressure sensor 5, the upstream pressure introduction hole 13, and the downstream pressure introduction hole 14 are connected. In this case, the upstream pressure introduction hole 13 and the downstream pressure introduction hole 14 form a bypass passage connecting the upstream side and the downstream side of the on-off valve 4. Therefore,
When the on-off valve 4 is closed, the pressure sensor 5 detects the pressure of the fluid flowing through the bypass passage, that is, the average pressure between the upstream pressure and the downstream pressure. FIG. 4B shows that the pressure sensor 5 is connected to the upstream pressure introduction hole 1.
3 shows the case where only the pressure on the upstream side is detected. FIG. 4C shows a case where the pressure sensor 5 is connected to the downstream pressure introduction hole 14 and detects only the downstream pressure. FIG. 4D shows a case where the pressure sensor 5 is not connected to either the upstream pressure introduction hole 13 or the downstream pressure introduction hole 14. In this case, when the pressure sensor 5 described in the second embodiment breaks down, the pressure sensor 5 can be replaced without closing the on-off valve 4. In this configuration, the same effect as described in the second embodiment can be obtained. When estimating the volume and the pipe capacity of the fluid passage after the on-off valve 4, it is possible to detect a pressure change by the pressure sensor 5 while flowing the fluid through the bypass passage with the on-off valve 4 closed. Since the flow rate of the fluid can also be measured by the flow meter 6, it can be estimated with high accuracy. The inner diameters of the upstream pressure introduction holes 13 and the downstream pressure introduction holes 14 shown in the above Examples 2 and 3 are about 0.1 [mm] or more, as long as the pressure of the fluid can be detected. It is enough. Therefore, when used as a bypass flow path, the inner diameter can be freely set to about 0.1 to 10 [mm] in accordance with the assumed pipe capacity.

(Embodiment 4) Next, a method for estimating the volume of the fluid passage downstream of the on-off valve 4, that is, the pipe capacity described in the second and third embodiments will be described.

For example, the fluid passage on the downstream side has an inner diameter of 20 [m
m] and a length of 30 [m]. That is, the downstream pipe capacity is
It was set to 9.4 [L]. Further, the pressure of the fluid on the upstream side is set to 200
[mmAq], the pressure on the downstream side is the atmospheric pressure (0 [m
mAq]). In addition, the bypass channel, that is, the inner diameter of the upstream pressure introduction hole 13 and the downstream pressure introduction hole 14 is 1 [mm],
The length was set to 100 [mm]. 200 differential pressure in bypass flow path
When [mmAq] is applied, fluid filling is started at a flow rate of about 25 [cc / sec], and as the pressure of the fluid in the downstream pipe increases, the differential pressure applied to the bypass decreases and the flow rate increases. Gradually decreases. FIG. 5 shows this state. In FIG. 5, the horizontal axis represents time [sec], and the left vertical axis represents downstream fluid pressure [mmAq].
On the right vertical axis is the flow rate of the fluid flowing through the bypass [cc / sec]
Is shown. A solid line 16 indicates a pressure increase on the downstream side when the gas is charged from the bypass flow path, and a dotted line 17 indicates a flow rate of the fluid flowing through the bypass flow path. That is, via the bypass flow path,
When the fluid is filled downstream for about 5 seconds, the flow rate of the fluid during that time gradually decreases from about 25 [cc / sec] to about 12 [cc / se].
c], and the pressure on the downstream side at that time is about 1 from 0 [mmAq].
It shows that it increases to 10 [mmAq]. Like this
By connecting the bypass flow path for a predetermined period of time and measuring the pressure change and the flow rate at that time, the downstream pipe capacity can be estimated. The bypass flow path can be realized by connecting the upstream pressure introduction hole 13 and the downstream pressure introduction hole 14 by operating a switching valve and operating the three-way valve 12 and the four-way valve 15 from the control unit 7.

(Embodiment 5) Next, Embodiment 5 of the present invention will be described.
This will be described with reference to FIG. The fluid flow measuring device of the fifth embodiment is provided with an upstream opening / closing valve 18 and a downstream opening / closing valve 19 as first and second fluid passage opening / closing means on the upstream side and the downstream side of the flow meter 6, respectively. The pressure sensor 5 was installed. In this configuration, when an abnormality such as a pressure drop occurs, the on-off valves 18 and 19 on the upstream and downstream sides are closed, and the pressure sensor 5 detects a change in the pressure of the fluid, thereby determining whether the fluid is normal or abnormal. be able to. Thereafter, by opening the on-off valve 18 on the upstream side or the on-off valve 19 on the downstream side, it is possible to determine whether an abnormality such as a pressure drop has occurred on the upstream side or on the downstream side. When the pressure sensor is out of order, both the upstream and downstream on-off valves 18 and 19 can be closed and replaced. In this case, the supply of the fluid is temporarily shut off, but the fluid on the upstream side and the downstream side is kept held, so that the fluid can be easily returned. That is, the pressure sensor 5
After the replacement, the on-off valve 18 on the upstream side is opened and closed for a certain period of time, the fluid is filled into the on-off valves 18 and 19, and it is confirmed that there is no abnormality. On-off valve 1
8 can be automatically and safely restored by sequentially opening and confirming. Also, two on-off valves 1 are provided on the upstream side and the downstream side.
Since it has 8, 19, the piping capacity on the downstream side can be easily estimated.

(Embodiment 6) A method for estimating the downstream pipe capacity in the case of the configuration described in the above-described Embodiment 5 will be described. That is, let Vs be the capacity of the closed space formed by the on-off valve 18 on the upstream side and on-off valve 19 on the downstream side, and let Vk be the pipe capacity on the downstream side. Now, the pressure of the fluid in the downstream pipe is reduced to 0.
[mmAq] (atmospheric pressure), and the pressure of the fluid on the upstream side is Pj. First, the on-off valve 18 on the upstream side is opened, and the on-off valve 19 on the downstream side is closed. Accordingly, the pressure in the closed space formed by the upstream and downstream on-off valves 18 and 19 becomes Pj. Next, the upstream side on-off valve is closed, and after confirming that there is no abnormality in the pressure, the downstream side on-off valve 19 is opened. If the fluid pressure at this time is Pk, Vs * Pj = (Vs + Vk) * Pk
Therefore, Vs * (Pj / Pk) = Vs + Vk. Therefore, the downstream pipe capacity Vk is Vk = Vs * [1- (Pj / Pk)].
It can be easily estimated. In addition, since the volume Vs of the closed space formed by the on-off valve 18 on the upstream side and the on-off valve 19 on the downstream side can be easily determined in advance, if the pressure Pk of the fluid on the downstream side is detected only, Can be estimated.

[0026]

As is clear from the above description, the following effects can be obtained according to the fluid flow measuring device of the present invention.

(1) Since pressure sensors are provided on the upstream and downstream sides of the on-off valve, it is possible to determine whether an abnormality such as a pressure drop has occurred on the upstream side or on the downstream side. . Further, the closed on-off valve can be opened and returned after confirming the safety on the downstream side.

(2) The closed on-off valve can be opened after confirming the safety on the downstream side. (3) Since the pressure sensor can be connected to the fluid passages on the upstream and downstream sides of the on-off valve via the switching valve, an abnormality such as a pressure drop occurs upstream or downstream of the on-off valve. Can be determined. By connecting the upstream and downstream pressure introduction holes, a bypass passage for the on-off valve can be provided.

(4) Even if the pressure sensor fails, it can be replaced without stopping the supply of fluid.

(5) By operating the switching valve, the downstream pipe capacity can be estimated.

(6) By operating the upstream and downstream open / close valves, the downstream pipe capacity can be estimated.

(7) By operating the switching valve, the safety on the downstream side can be confirmed, and the closed on-off valve can be opened.

(6) By operating the upstream and downstream on-off valves, the safety on the downstream side can be confirmed, and the closed on-off valves can be opened.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a fluid flow measurement device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a fluid flow measuring device according to Embodiments 2 and 3 of the present invention.

FIG. 3A is a diagram illustrating a first operation of a three-way switching valve of the device 2; FIG. 3B is a diagram illustrating a second operation of the three-way switching valve; FIG. Diagram explaining operation

FIG. 4A is a diagram illustrating a first operation of a four-way switching valve in a fluid flow measurement device according to a third embodiment of the present invention. FIG. 4B is a diagram illustrating a second operation of a four-way switching valve in the device. C) A diagram illustrating a third operation of the four-way switching valve in the same device. (D) A diagram illustrating a fourth operation of the four-way switching valve in the same device.

FIG. 5 is a characteristic diagram of a pressure and a flow rate in the fluid flow rate measuring devices according to the fourth and fifth embodiments of the present invention.

FIG. 6 is a configuration diagram of a fluid flow measurement device according to a fifth embodiment of the present invention.

FIG. 7 is a configuration diagram of a conventional fluid flow measurement device.

[Explanation of symbols]

 Reference Signs List 4 fluid passage opening / closing means 6 passing flow rate measuring means 7 control unit 10 first pressure measuring means 11 second pressure measuring means 12 switching valve 13 upstream pressure introducing hole 14 downstream pressure introducing hole 15 four-way switching valve 16 pressure characteristic curve 17 Flow characteristic curve 18 First fluid passage opening / closing means 19 Second fluid passage opening / closing means

Claims (7)

[Claims] 1. A first pressure measuring means for measuring a pressure of a fluid, a fluid passage opening / closing means for opening / closing a fluid passage, a second pressure measuring means for measuring a pressure of the fluid, and a passing flow rate for measuring a passing flow rate of the fluid. Measuring means is sequentially arranged from upstream to downstream of the fluid passage, and a supply state of the fluid is determined from measurement results of the first and second pressure measuring means and the flow rate measuring means. A flow rate measuring device that operates a passage opening / closing unit and notifies a determination result by a notifying unit. 2. An upstream pressure introducing hole for measuring the pressure of the fluid, a fluid passage opening / closing means for opening and closing the fluid passage, a downstream pressure introducing hole for measuring the pressure of the fluid, and measuring the flow rate of the fluid. The flow rate measuring means is sequentially configured from upstream to downstream of the fluid passage, and the upstream pressure introducing hole or the downstream pressure introducing hole is connected to a pressure measuring means for measuring the pressure of the fluid via a switching valve, A flow rate measuring device for judging a supply state of a fluid from a measurement result of the pressure measuring means and a measurement result of the flow rate measuring means, operating the fluid passage opening / closing means by a control means, and notifying the judgment result by a notifying means. 3. The flow measuring device according to claim 2, wherein the switching valve has three connection ports, and any two of the connection ports pass through the three connection ports. 4. The flow measuring device according to claim 2, wherein the switching valve has four connection ports, and any three of the connection ports pass therethrough. 5. An upstream pressure introducing hole for measuring a pressure of a fluid, a fluid passage opening / closing means for opening / closing a fluid passage, a downstream pressure introducing hole for measuring a pressure of the fluid, and measuring a flow rate of the fluid. The flow rate measuring means is sequentially arranged from the upstream to the downstream of the fluid passage, and the upstream pressure introducing hole or the downstream pressure introducing hole is connected to a pressure measuring means for measuring the pressure of the fluid via a switching valve. Determining the supply state of the fluid from the measurement result of the pressure measurement means and the measurement result of the flow rate measurement means, operating the fluid passage opening / closing means by a control means; The opening / closing means is closed, and the connection port of the switching valve is sequentially selected to measure the pressure in the upstream pressure introduction hole or the downstream pressure introduction hole, and to measure the volume of the downstream fluid passage. Piping capacity measurement method. 6. A first fluid passage opening / closing means for opening / closing a fluid passage, a pressure measuring means for measuring a pressure of a fluid, a second fluid passage opening / closing means for opening / closing a fluid passage, and a passage for measuring a flow rate of the fluid. The flow rate measuring means is sequentially arranged from the upstream to the downstream of the fluid passage, and the supply state of the fluid is determined from the measurement result of the pressure measuring means and the measurement result of the flow rate measuring means, and the fluid passage opening and closing is controlled by the control means. A flow rate measuring device that operates means and notifies the determination result by the notifying means. 7. A first fluid passage opening / closing means for opening / closing a fluid passage, a pressure measuring means for measuring a pressure of a fluid, a second fluid passage opening / closing means for opening / closing a fluid passage, and a passage for measuring a flow rate of the fluid. The flow rate measuring means is sequentially arranged from the upstream to the downstream of the fluid passage, and the supply state of the fluid is determined from the measurement result of the pressure measuring means and the measurement result of the flow rate measuring means. Is operated to notify the determination result by the notifying means, and the pressure of the closed space formed by the first fluid passage opening and closing means and the second fluid passage opening and closing means, and the second fluid passage opening and closing A pipe volume measuring method for measuring a volume of a fluid passage on a downstream side from a pressure change when a fluid is released.