JP2009063401A - Mass flow meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mass flow meter having almost no loss head in a detection section for calculating a mass flow value even when mass fluid is consumed simultaneously, always calculates exact mass flow value over long term to the increase/decrease in flow rate, and reduces the installation cost though it has an emergency cut-off function. <P>SOLUTION: The flow meter calculates a mass flow value of the fluid flowing in a fluid passage with a cross type rotary valve 14 disposed in the fluid passage and supported in an outer casing 12 so as to rotate freely. The cross type rotary valve 14 is configured with a cross tube 15 including 2 straight tubes 15-1 and 15-2, and in a fully opened state of the cross type rotary valve 14, the one straight tube 15-1, a flow-in tube 34 connected to the outer casing 12 and a flow-out tube 36 are aligned linearly, and a cumulative integration amount of the mass flow value is calculated based on fluid pressure received at the cross tube 15. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a mass flow meter that calculates a cumulative accumulated amount of a fluid flow rate (mass flow) flowing through a fluid pipe line in which a cross-shaped rotary valve that is normally fully open and can be urgently closed is disposed.

  2. Description of the Related Art Conventionally, a mass flow meter that calculates the accumulated amount of fluid flow values flowing through a water pipe or the like is known that is calculated from the rotational speed of an impeller (see Patent Document 1). FIG. 6 is a schematic partial cross-sectional view of such a mass flow meter.

  As shown in FIG. 8, in the mass flow meter 1, the holding tube 3 rises from the water pipe 2, and the meter case 4 is assembled in the holding tube 3 in a state where the entire circumference is sealed. The meter case 4 is formed of a material that allows magnetic force to pass through, and an impeller 5 whose number of rotations increases or decreases in accordance with the flow of water is provided in the area of the water pipe 2 below the meter case 4. A magnet 7 that rotates together with the support shaft 6 is disposed above the impeller 5 that is rotatably supported by the support shaft 6. Inside the meter case 4, there is a detection sensor 8 that detects the rotational speed of the impeller 9, and a measuring circuit section 9 that converts the rotational speed from the detection sensor 8 into a flow rate of water.

Japanese Patent Laid-Open No. 2002-270908 (FIG. 1)

  However, the mass flow meter 1 in Patent Document 1 uses the impeller 5 supported by the support shaft 6 in order to detect the number of rotations, but since it can reach the consumption side while rotating the impeller, it is lost water in the rotating part. When tap water is supplied to a general house with many heads and toilets, bathrooms, washrooms, etc. where water is used, the total size of the head loss is an increase in supply heads and the effective use of energy. It was not desirable from the viewpoint. When a large amount of water is consumed at the same time, a large amount of water passes through the impeller, and the rotation of the impeller 5 cannot catch up and there is a possibility that an accurate mass flow value cannot be calculated. In addition, if the impeller 5 is used for a long period of time, the followability of rotation with respect to changes in the flow rate decreases due to wear of the support shaft 6 or damage to the blades themselves, so that the impeller 5 is periodically inspected, maintained, or replaced. It took me. In a pipeline system having such a mass flow meter 1, an emergency shut-off valve is generally provided along with an abnormal outflow of fluid or the need to shut off the flow in the pipeline at the time of an earthquake. The increase in cost was inevitable.

  The present invention has been made paying attention to such problems, and even when a large amount of fluid is consumed at the same time, there is almost no loss head in the detection unit for calculating the mass flow value, and the flow rate is It is an object of the present invention to provide a mass flow meter that can always calculate an accurate mass flow value over a long period of time, and can reduce the installation cost even though the emergency shutoff has a function.

In order to solve the above problems, a mass flow meter according to claim 1 of the present invention flows in a fluid pipe line by a cross-shaped rotary valve disposed in the fluid pipe line and rotatably supported in an outer casing. In the flow meter for calculating the mass flow value of the fluid, the cross-shaped rotary valve is configured by a cross pipe composed of two orthogonal straight pipes, and when the cross-type rotary valve is in a fully opened state, one of the cross pipes The straight pipe is aligned linearly with respect to the inflow pipe and the discharge pipe connected to the outer casing, and the communication between the inflow pipe and the discharge pipe is established by rotating the cross-shaped rotary valve. A signal obtained based on the fluid pressure received by the cruciform tube at the time of full opening is input to the controller, and the calculation unit of the controller continuously calculates the average velocity of the fluid flowing in the cruciform tube. It is characterized by calculating the cumulative 蓄算 amount of Sufuro value.
According to this feature, in the fully open state of the cross-shaped rotary valve, there is no valve body that resists the flow of fluid like the conventional butterfly valve, so it is possible to create a fluid flow with almost no fluid loss It is. Further, when the fluid flow is interrupted by the rotation of the cross-shaped rotary valve, it is not necessary to rotate the fluid flow to 90 degrees as in the case of the conventional butterfly valve, so that the time required for the interruption can be shortened. Furthermore, even if the opening packing of one straight pipe used at the time of full opening is damaged, the cross pipe can be rotated 90 degrees and the other straight pipe can be used as a normal pipe at the time of full opening.

A mass flow meter according to claim 2 of the present invention is the mass flow meter according to claim 1, wherein a signal obtained based on the fluid pressure is transmitted to an outer casing facing the other straight pipe of the cross pipe. It is a fluid drag signal from a provided strain gauge.
According to this feature, since the strain gauge can be provided in the outer casing facing the other straight pipe of the cross tube, there is almost no loss head in the flow of the fluid when fully opened.

The mass flow meter according to claim 3 of the present invention is the mass flow meter according to claim 1 or 2, wherein the cruciform tube is rotated by an emergency closing output signal from a controller to connect the inflow pipe and the discharge pipe. The communication is cut off.
According to this feature, the rotary type shut-off valve can be appropriately operated by the controller at the time of an earthquake, fluid leakage, non-payment of charges, etc., so that the mass flow meter can be used widely.

The mass flow meter according to claim 4 of the present invention is the mass flow meter according to claim 3, wherein the emergency closing output signal from the controller is generated by the magnitude of irregular pulsating flow generated in the fluid conduit. It is characterized by having.
According to this feature, an earthquake can be detected by measuring an irregular pulsating flow generated in a fluid pipe without installing a seismometer during an earthquake.

A mass flow meter according to claim 5 of the present invention is the mass flow meter according to any one of claims 1 to 4, wherein the cross-shaped rotary valve is arranged with the other straight pipe in a vertical state. It is characterized in that an air valve is provided on the upper part of the.
According to this feature, since the air valve can be used for intake and exhaust of air in the fluid pipe, unlike the conventional meter-reading flow meter, which cannot be installed higher than the ground due to the inability to intake and exhaust air, It is possible to install a mass flow meter higher than the ground up to an easy-to-see position.

A mass flow meter according to a sixth aspect of the present invention is the mass flow meter according to any one of the first to fifth aspects, wherein a cumulative accumulated amount of the mass flow value is calculated every predetermined number of days, and the mass storage meter is stored in the host computer. It is characterized by having means for transmitting calculation information.
According to this feature, there is no need to provide order software on the host computer, and the host computer only needs general-purpose software that divides and accumulates information from each controller, greatly increasing the investment amount for the automatic meter reading system. Can be reduced.

  Examples of the present invention will be described below.

  FIG. 1 is a schematic front view and a partially enlarged sectional view of a mass flow meter with the cross-shaped rotary valve of the present invention fully opened, FIG. 2 is a side view of FIG. 1, and FIG. It is an exploded perspective view of the outer casing in a state, (b) is a perspective view of the packing inserted between the half outer casing, FIG. 4 is a perspective view of the cross-shaped rotary valve and a partially enlarged view thereof, FIG. 5 is a schematic front view of the mass flow meter in a state where the pipe is blocked by the cross-shaped rotary valve, FIG. 6 is a schematic explanatory diagram of the mass flow meter for calculating the flow rate, and FIG. 7 is used in the mass flow meter. FIG. In the following description of FIG. 1, the left side of the paper is the left side of the mass flow meter, the right side of the paper is the right side of the mass flow meter, and similarly, the upper part of the paper is the upper part of the mass flow meter and the lower part of the paper is the lower part of the mass flow meter.

  The mass flow meter of the present invention is used, for example, as a water meter instrument for calculating the amount of monthly tap water used for collecting water charges, and can shut off tap water in case of unauthorized use or emergency. It is. As shown in FIGS. 1 and 2, a mass flow meter 10 inserted in a tap water channel pipe between a main plug and a faucet has a cross-shaped rotary valve 14 rotatably supported in an outer casing 12, and a cross-shaped rotation valve. It comprises a valve drive unit 16, a controller 18 such as a microcomputer incorporating a calculation unit for calculating the mass flow value of tap water, and a display unit 20 for displaying the mass flow value. The drive unit 16 is a motor (not shown). The drive shaft 22 of the cross-shaped rotary valve 14 can be driven to open and close. However, in the event of a motor failure or the like, the drive shaft 22 and the reduction gear G are connected to each other via the clutch 24 so that the drive shaft 22 can be manually driven by the operation handle 26. It is like that.

  The controller 18, the reduction gear G, or the clutch 24 is housed in a case 28 that can be opened and closed (indicated by a two-dot chain line in FIG. 2), and a display unit 20 having various operation buttons and a liquid crystal display screen is placed on the upper surface of the case 28. ing. As shown in FIG. 2, the controller 18 receives a signal from the strain gauge 30, calculates a mass flow value, accumulates and accumulates the value for each month, and displays it on the display unit 20. A motor drive signal is transmitted to the drive unit 16 so that the fluid flow is closed by driving the cross-shaped rotary valve 14. Since the strain gauge 30 can be provided on the inner wall 42c of the outer casing 12 facing the other straight pipe 15-2 of the cross tube 15, there is no loss head in the fluid flow when fully opened.

  As shown in FIG. 3A, the outer casing 12 includes divided casings 12-1 and 12-2 having a semicircular cross section so that the cross-shaped rotary valve 14 can be easily assembled. -1 is connected to the inflow pipe 34 connected to the upstream main plug, and the other casing 12-2 is connected to the outflow pipe 36 serving as a discharge pipe from the cross-shaped rotary valve 14 connected to the downstream faucet. Yes.

  After the cross-shaped rotary valve 14 is housed in the casings 12-1 and 12-2, the packings 38a and 38b shown in FIG. 3B are inserted between the split mating surfaces 12a and 12b of the split casings, A pair of upper and lower mounting flanges 12 c of each casing are aligned and tightened with bolts 40. When the cruciform rotary valve 14 is housed in the split casings 12-1 and 12-2, the support shaft 14a of the cruciform rotary valve 14 shown in FIG. The drive shaft 22 of the cruciform rotary valve 14 is inserted into the fitting hole 12e formed in this way through a bearing (not shown), and the boss provided at a position facing the boss portion 12d of both split casings. The front end portion extending from the outer casing 12 is connected to the drive portion 16 (see FIG. 2), and is inserted into the fitting hole 12g formed by combining the portions 12f.

  Next, the structure of the cross-shaped rotary valve 14 will be described with reference to FIGS. The cross-shaped rotary valve 14 is constituted by a cross tube 15 composed of two orthogonal straight tubes 15-1 and 15-2, and the inside thereof is formed in a hollow pipe shape so that fluid can be conducted. The outer side of the cross tube 15 is surrounded by an annular band 42 having a U-shaped cross section that is open on the outer peripheral surface side. As shown in the enlarged view of FIG. 4, the annular band 42 includes a ring-shaped inner wall 42 c and an inner wall 41. A ring-shaped upper piece 42a and a ring-shaped lower piece 42b extending radially outward from the upper and lower ends are welded to the inner wall 42c of the annular band 42 at four outer end portions of the straight pipes 15-1 and 15-2. Has been.

  In the vicinity of the inner wall 42c where the straight pipes 15-1 and 15-2 are welded, two partition plates 42d and 42d for connecting the ring-shaped upper piece 42a and the ring-shaped lower piece 42b of the annular band 42 in a sealed state are provided. Thus, the cabin 44 surrounded by the four surfaces of the two partition plates 42d and 42d and the upper and lower ring-shaped upper and lower pieces 42a and 42b is formed.

  The opening seal part 46a surrounds the opening part side periphery of the four cabins 44, and as shown in FIG. 2, one straight pipe 15-1 is connected to the outer casing, the inflow pipe 34 and the outflow pipe 36. In the fully open state aligned in a straight line, the opening seal portion 46a is in sealing contact with the inner wall 12h (see FIG. 3a) of the outer casing, so that the fluid introduced from the inflow pipe 34 passes directly through the cabin 44. It can flow toward the outflow pipe 36 via the pipe 15-1. Since the cabin 44 on the outflow pipe 36 side of the straight pipe 15-1 is also in contact with the inner wall 12h of the outer casing in a sealing manner by the opening seal portion 46a, all the fluid flowing into the cross-shaped rotary valve 14 does not leak out. 36.

  Further, ring-shaped seal portions 46b and 46b are respectively provided on the outer peripheral surfaces of the ring-shaped upper piece 42a and the ring-shaped lower piece 42b of the annular band 42, and the opening seal portion 46a and the ring-shaped seal portion 46b are connected to each other. A seal portion 46c is provided.

  Thus, in the fully open state of the cross-shaped rotary valve 14, there is no valve body that resists the flow of fluid, such as a conventional butterfly valve, so that it is possible to create a fluid flow with almost no fluid loss. . Further, in the fully open state of the cross-shaped rotary valve 14, the fluid flows into the other straight pipe 15-2, but does not leak out from the cabin 44 by the opening seal portion 46 a of the cabin 44.

  The cabin 44 above the other straight pipe 15-2 communicates with an air valve 48 connected to a boss portion 12i formed on the upper portion of the outer casing 12. This air valve 48 has a float valve that moves up and down in accordance with the water level introduced into the cross-shaped rotary valve 14, releases the air present in the cross tube 15 to the outside, and externally when the water level drops. This is a known air valve that takes in air from the air. In this way, air can be sucked and exhausted by the air valve 48. Thus, unlike the conventional meter-reading flowmeter that cannot be placed higher than the ground due to the fact that air cannot be sucked and exhausted, the present invention is provided to a position where the meter reader can easily see. It is also possible to install a mass flow meter.

  Next, a method for blocking the cross-shaped rotary valve 14 in an emergency will be described with reference to FIG. When a motor drive signal is transmitted from the fully open state of the cross-shaped rotary valve 14 shown in FIG. 1 to the motor that drives the drive unit 16 in an emergency, the drive shaft 22 of the cross-shaped rotary valve 14 rotates to the right and is driven. The straight pipe 15-1 integrally connected to the shaft 22 also rotates to the right by about 45 degrees, and the cabin 44 of the straight pipe 15-1 that is in communication with the inflow pipe 34 is cut off.

  That is, when the partition plate 42d forming the cabin 44 passes through the opening of the inflow pipe 34 by the right rotation of the straight pipe 15-1, the fluid flowing from the inflow pipe 34 into the cross-shaped rotary valve 14 is transferred to the straight pipe 15-. 1 and straight pipe 15-2, the opening seal portion 46a of the cabin 44, the ring-shaped seal portions 46b and 46b provided on the outer peripheral surfaces of the ring-shaped upper piece 42a and the ring-shaped lower piece 42b, and the connecting seal portion 46c, respectively. Therefore, the fluid introduced from the inflow pipe 34 cannot flow out beyond the U-shaped annular band 42 between the straight pipe 15-1 and the straight pipe 15-2, and the U-shaped annular section. It is confined in the band 42 and does not flow toward the outflow pipe 36.

  Next, a method of integrating the flow rate flowing through the cross-shaped rotary valve 14 will be described with reference to FIG. When the cross-shaped rotary valve 14 is fully open, the cabin 44 below the other straight pipe 15-2 is also sealed, and a strain gauge 30 is embedded in the inner wall 12h of the outer casing 12 facing the cabin 44. By converting the drag force received by the strain gauge 30 into an electrical signal and inputting it to the controller 18 to calculate the pressure of the fluid flowing in the cross tube 15 passage and monitoring the change, for example, every predetermined time The flow rate flowing through the cross-shaped rotary valve 14 can be integrated.

In the schematic explanatory diagram of FIG. 6, the flow velocity at the point O which is the center of the cross tube 15 is expressed as V ₁ , When the static pressure P ₁ , the pressure in the lower portion of the other straight pipe 15-2 calculated from the strain gauge 30 is P ₂ , and the total delivery pressure for discharging to the inflow pipe 34 is P, the total pressure at the point O (total head) ) T is represented by T = PL. Here, L is a pipe resistance value from the pump delivery point to the point O, and is a numerical value already known as an experimental value in advance depending on the material of the pipe, the pipe diameter, and the like.

Since the strain gauge 30 is separated from the point O by a distance h, the relational expression P ₂ = P ₁ + gh is established. Therefore, if the density of water is ρ, T = PL = (V ₁ ² ρ / 2) + P ₁ = (V ₁ ² ρ / 2) + P ₂ -ρgh, and V ₁ ² = 2 (P−L The magnitude of the flow velocity V ₁ can be obtained from −P ₂ + gh) / ρ. If the flow velocity V ₁ is known, it is calculated an average flow velocity V of the road-tube by the controller by a general method.

  Since the magnitude of the average flow velocity V in the pipe line changes every time depending on the usage condition of tap water, the mass flow value used (here, the mass flow value is the amount of fluid that has moved in the pipe pipe due to the use of fluid). ) Is obtained as a value obtained by integrating the product of the average flow velocity V and the cross-sectional area of the straight pipe 15-1 with the usage time. If the mass flow value is accumulated and accumulated every time tap water is used in this way, the total total usage can be calculated every day or every month and used as a mass flow meter.

  Next, the operation of the controller will be described with reference to FIG. The controller 18 includes an input unit 18-1, an output unit 18-2, a calculation unit 18-3, and a storage unit 18-4. As a signal received by the input unit 18-1, a drag F received by the strain gauge 30 is obtained. A signal F1 converted as an electrical signal, a vibration (or seismic intensity from the earthquake detector) signal F2 from a vibration sensor directly attached to the case 28 containing the controller 18 or the outer casing 12 of the cross-shaped rotary valve 14 , Information signal F3 from a charge card such as a prepaid card, command signal F4 from various operation buttons provided on display unit 20, command signal F5 from transmission / reception unit 52 that can be transmitted / received to / from base station 50 by an antenna, etc. It is.

  On the other hand, as a signal transmitted from the output unit 18-2, a command signal O1 to the valve driving unit 16 for opening and closing the cross-shaped rotary valve 14, a display for displaying characters and the like on the liquid crystal display screen of the display unit 20 An instruction signal O2 and an information signal O3 output to the transmission / reception unit 52 in order to transmit necessary information to the management center 56 are included. The information signal received by the transmission / reception unit 52 is transmitted to the base station 50 by an antenna, and can be sent from the base station to the management center 56 via a public line 54 such as the Internet. As a matter of course, the command signal from the management center 56 is sent to the transmission / reception unit 52 via the public line 54 and can be input to the controller 18 from the transmission / reception unit 52 as the signal F5.

  Since the mass flow meter 10 of the present invention includes the controller 18 described above, the usage amount of tap water is simply calculated based on the signal F1 and the value is displayed on the display unit 20, and various functions are added. be able to. That is, the command signal O1 (emergency closing output signal) for closing the cruciform rotary valve 14 is output to the valve drive unit 16 with the amplitude and seismic intensity of the F2 signal, and the fluid introduced from the inflow pipe 34 is shut off. If the prepaid card is inserted, the F3 signal outputs a command signal O1 for opening the cross-shaped rotary valve 14 to the valve drive unit 16 so that tap water can be used, or if there is no remaining balance, the cross-shaped rotation The valve 14 can be closed.

  In addition, as F2 signal, a measuring instrument such as a vibration detector or seismic detector is directly attached to the tap water pipe, and the magnitude of the amplitude and seismic intensity is measured. The irregular pulsating flow that occurs is regarded as a fluctuation of the drag F by the strain gauge 30, and compared with the drag fluctuation pattern at the time of the earthquake stored in the storage unit 18-4 of the controller 18, it is determined whether or not it is an earthquake. Means to do so is also inherent in the controller 18. In this case, for example, when the acceleration vibrates at 160 gal or more, it is determined that the earthquake is a large earthquake, and the command signal O1 for closing the cross-shaped rotary valve 14 is output as an emergency closing output signal. At the same time, the system notifies the management center 56 at the same time. Thereby, the management center 56 side can grasp the distribution status of the magnitude of the earthquake over a wide range by totaling and analyzing the information from each controller.

  On the other hand, the display unit 20 is equipped with various operation buttons, scrolling the mass flow value for each month, displaying the amount of money used based on the amount of water used, Etc.), there are buttons for reporting to the management center 56, etc., which are input as the signal F4, processed by the calculation unit 18-3, and then the information stored in the storage unit 18-4 is displayed from the output unit 18-2. The command signal O2 is transmitted to the display unit 20 or the information signal O3 is transmitted to the transmission / reception unit 52. Further, using the F5 signal, the management center 56 issues a command to open / close the cross-shaped rotary valve 14 to the valve drive unit 16 or displays a message stored in advance in the storage unit 18-4 of the controller 18 on the display unit 20. It can also be made.

  In addition, the mass flow meter of the present invention can also construct an automatic meter reading system using the controller 18. Specifically, this is a system in which the controller 18 sends the total amount of water usage to the host computer in the management center 56 every predetermined number of days, for example every 15 or 30 days. The total amount of water usage stored in the storage unit 18-4 is taken out, the address of the host computer is read out, and the information signal O3 is sent through the transmission / reception unit 52 and the public line 54 (including the power line communication line called PLC). Information is transmitted to a host computer in the management center 56.

  By constructing such an automatic meter reading system, it is not necessary for the host computer to have order software for collecting accumulated water usage information from the host computer to the individual controllers 18. Only general-purpose software that divides and accumulates information from 18 can be used, and the investment amount for the automatic meter reading system can be greatly reduced. Since this automatic meter-reading apparatus uses the controller 18 used in the mass flow meter of the present invention, the automatic meter-reading system can be implemented selectively in sequence from where the controller is provided.

  Although the embodiments of the present invention have been described with reference to the drawings, the specific configuration is not limited to these embodiments, and modifications and additions within the scope of the present invention are also included in the present invention. For example, in the above-described embodiment, the example of using as a water meter instrument for a tap water channel pipe has been described. However, the present invention is not limited to tap water and can be used as a general liquid or gas accumulator, and as a gas meter instrument. Needless to say, it can also be used.

  In the above-described embodiment, the example in which the cross-shaped rotary valve 14 is rotated to the right by approximately 45 degrees to block the fluid flow has been described. Moreover, since the partition plate 42d of the cabin 44 can block the fluid flow at a rotation angle that passes through the opening of the inflow pipe 34, it can be blocked even at 45 degrees or less. Therefore, since it is not necessary to rotate 90 degrees like the conventional butterfly valve, the time required for shut-off can be shortened.

  Furthermore, in the above-described embodiment, the cross-shaped rotary valve 14 has been described as being installed with the air valve 48 on the upper side. However, when the cross-type rotary valve 14 is not disposed higher than the ground or when gas is used as the fluid, It is also possible to install it in a place.

  The opening seal portion 46a facing the inflow pipe 34 and the outflow pipe 36 of one pipe 15-1 used when the cross-shaped rotary valve 14 is fully opened is directly subjected to a pulse pressure based on a water hammer generated in the pipe, and thus deteriorates. Although it is easy to proceed, it is possible to rotate the cross tube 90 degrees at the time when the deterioration progresses and use the other straight tube 15-2 as a regular tube when fully opened.

FIG. 2 is a schematic front view of a mass flow meter with a cross-shaped rotary valve of the present invention fully opened and a partially enlarged cross-sectional view thereof. FIG. 6 is a flow chart of a controller used in a mass flow meter. It is a schematic front view of the mass flow meter in which the butterfly valve in Example 1 of this invention is a valve closing state. It is a side view of FIG. (A) is an exploded perspective view of the outer casing in a half state, and (b) is a perspective view of the packing inserted between the half outer casings. It is the perspective view of a cross-type rotary valve, and its one part enlarged view. It is a schematic front view of a mass flow meter in a state where a pipe line is blocked by a cross-shaped rotary valve. It is a schematic explanatory drawing of the mass flow meter for calculating a flow rate. It is a flowchart of the controller used for the mass flow meter. It is a general | schematic fragmentary sectional view of the conventional mass flow meter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Mass flow meter 12 Outer casing 14 Cross-shaped rotary valve 15 Cross pipe 15-1 One straight pipe 15-2 The other straight pipe 16 Valve drive part 18 Controller
18-1 Input unit 18-2 Output unit 18-3 Calculation unit 18-4 Storage unit 20 Display unit 24 Clutch 26 Operation handle 28 Case 30 Strain gauge 34 Inflow pipe 36 Outflow pipe (discharge pipe)
38a, b Packing 42 Annular belt 44 Cabin 46a Opening seal 46b Ring-shaped seal 46c Connection seal 48 Air valve
50 Base station 52 Transceiver 54 Public line 56 Management center

Claims (6)

  In a flow meter for calculating a mass flow value of a fluid flowing in a fluid pipe by means of a cross-shaped rotary valve disposed in a fluid pipe and rotatably supported in an outer casing, the cross-type rotary valve is configured to have two orthogonal cross valves. When the cross-type rotary valve is fully open, one of the cross pipes is linear with respect to the inflow pipe and the discharge pipe connected to the outer casing. A signal obtained on the basis of the fluid pressure received by the cruciform tube when the cruciform tube is fully opened and the communication between the inflow tube and the discharge tube is blocked by the cruciform tube by rotating the cruciform rotary valve. A mass flow meter, characterized in that a cumulative amount of mass flow values is calculated by inputting to a controller and continuously calculating an average velocity of a fluid flowing through the cross tube by a calculation unit of the controller.   The mass flow meter according to claim 1, wherein the signal obtained based on the fluid pressure is a fluid drag signal from a strain gauge provided in an outer casing facing the other straight pipe of the cross tube.   The mass flow meter according to claim 1 or 2, wherein the cross tube is rotated by an emergency closing output signal from a controller and communication between the inflow tube and the discharge tube is blocked.   4. The mass flow meter according to claim 3, further comprising means for generating an emergency closing output signal from the controller according to an irregular pulsating flow generated in the fluid conduit.   The mass flow meter according to any one of claims 1 to 4, wherein the cross-shaped rotary valve is arranged with the other straight pipe in a vertical state and an air valve is provided on an upper portion of the straight pipe.   6. The mass flow according to claim 1, wherein the controller includes means for calculating a cumulative accumulation amount of the mass flow value every predetermined number of days and transmitting the calculation information to a host computer. Meter.

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