JP3144986B2 - Flowmeter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow meter for measuring and displaying a flow rate of a fluid such as a gas.

[0002]

2. Description of the Related Art In a flow meter such as a gas meter, the flow rate of a gas flowing in a pipe is measured by a flow rate sensor such as a hot-wire anemometer, and the flow rate is calculated from the flow rate and displayed.

Here, in the conventional flow meter, FIG.
As shown in (1), one flow rate sensor 1 is disposed at the center of the gas flow path in the pipe 2, and the flow velocity at the flow path center obtained by the flow rate sensor 1 is calculated by the flow rate calculation unit 3 as the flow rate. Then, it is displayed on the display unit 4.

[0004]

However, the piping 2
The medium flow velocity has a different flow velocity distribution on the same cross section due to a difference in pipe shape, the presence of a bent portion, a branch portion, or the like, or the magnitude of the flow rate. For this reason, with a conventional flowmeter that can detect only the flow velocity at the center of the cross section of the gas flow path, the measurement value of the flow velocity cannot be obtained accurately, and as a result, a wide range of flow rate cannot be accurately measured. There was a problem.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a flow meter capable of improving the measurement accuracy of a flow rate sensor and accurately measuring a wide range of flow rate.

[0006]

[Means for Solving the Problems]

[0007]

[0008] In the flowmeter according to the first aspect, a guide member insertion portion provided at an arbitrary position on a wall surface along the longitudinal direction of the pipe so as to penetrate the wall surface, and the pipe is inserted through the guide member insertion portion. And a hollow guide member having a plurality of first fluid passage holes along the flow direction of the fluid, and a plurality of first fluids of the guide member being inserted into the guide member and being inserted into the guide member. A plurality of second holes corresponding to the passage holes
Flow rate sensor unit having a plurality of fluid passage holes, and a plurality of flow rate sensors arranged to face each of the plurality of second fluid passage holes, and output signals of the plurality of flow rate sensors in the flow rate sensor unit. And an average flow velocity calculating means for calculating an average value of flow velocity at a plurality of points in the fluid flow path, and a flow rate calculating means for calculating a flow rate of the fluid based on a calculation result of the average flow rate calculating means. It is provided.

In this flow meter, the flow rate sensor unit is inserted from the outside into the guide member, so that the flow meter can be easily installed.

According to a second aspect of the present invention, in the flow meter, a plurality of guide member insertion portions provided so as to penetrate the wall surface on the same cross section orthogonal to the longitudinal direction of the pipe, and a plurality of guide member insertion portions. And a plurality of hollow guide members having at least one first fluid passage hole along the flow direction of the fluid, and inserted into each of these guide members,
A plurality of guide members each having at least one second fluid passage hole corresponding to the first fluid passage hole, and at least one flow rate sensor disposed to face the second fluid passage hole; Flow rate sensor units, average flow rate calculating means for receiving each output signal of a plurality of flow rate sensors in these flow rate sensor units, and calculating an average value of flow rates at a plurality of points in the fluid flow path; Flow rate calculating means for calculating the flow rate of the fluid based on the calculation result of the calculating means.

This flow meter has a plurality of flow rate sensor units, and more flow rate sensors can be arranged on the same cross section, so that the measurement accuracy is further improved.

According to a third aspect of the present invention, there is provided a flow meter according to the second aspect , wherein the guide member is formed in a cylindrical shape so as not to obstruct the flow of the fluid.

According to a fourth aspect of the present invention, there is provided the flow meter according to the third aspect, wherein the guide member is provided in the inner hollow portion along at least one of the first fluid passage holes along the longitudinal direction. And a semi-cylindrical unit insertion section on each side of the partition section, while the flow rate sensor units each have a unit insertion section for the guide member. And two unit members each having a semi-cylindrical shape that can be inserted into the unit, and each of these unit members is provided with at least one second fluid passage hole facing the third fluid passage hole, and is provided on the downstream side. The flow rate sensor is arranged corresponding to the second fluid passage hole on the unit member side arranged in the above.

According to a fifth aspect of the present invention, there is provided a flow meter according to the third aspect , wherein the guide member is provided in the inner hollow portion along at least one of the first fluid passage holes along the longitudinal direction. It has two partition portions formed with three fluid passage holes, and has three unit insertion portions with these partition portions interposed therebetween, while the flow rate sensor units are each provided in a unit insertion portion of the guide member. Insertable for 3
At least one second member facing each of the third fluid passage holes.
And a flow rate sensor is arranged corresponding to the second fluid passage hole of the unit member arranged in the middle with respect to the flow direction.

[0015] The flow meter according to the sixth aspect is characterized in that the first to fourth aspects are as follows.
5. The flowmeter according to any one of 5 , wherein an index portion for adjusting the installation direction of the guide member is provided on the outer wall of the guide member corresponding to the first fluid passage hole, whereby the guide is provided. The members can be installed accurately.

[0016]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a schematic sectional structure of a flow meter according to an embodiment of the present invention, and FIG. 2 shows a sectional structure in the direction of arrows AA in FIG. In the flow meter of the present embodiment, a cylindrical sensor unit 13 is disposed at a predetermined position in a pipe 11 through which a fluid, for example, gas a passes, so as to be orthogonal to the flow direction of gas a. The sensor unit 13 has four fluid passage holes 13 ₁ ,
13 ₂ , 13 ₃ , and 13 ₄ are provided. A plurality of, for example four flow sensors of a position facing thereto the fluid passage holes _131-134 each sensor unit 13 12 _1, 1
2 _2, 12 _3, 12 ₄ are disposed.

That is, in the flow meter of this embodiment, the pipe 1
4 at different positions on the same cross section in the gas flow path in 1.
In which is disposed pieces of the flow rate sensor 12 ₁ to 12 ₄ tandem to. Flow sensors 12 ₁ to 12 ₄ each detected signal is input to the average flow velocity calculating unit 14 as shown in the block diagram in FIG. 3, the average value of the flow velocity measurements in the mean flow velocity calculating unit 14 (Va) is calculated You. The flow rate average value (Va) calculated by the average flow rate calculation unit 14 is converted into a flow rate Q by the following equation 1 in the flow rate calculation unit 15, and then the display unit 16
Is displayed in. Note that the average flow velocity calculating section 14 and the flow rate calculating section 15 are realized by the microcomputer 17.

[0019]

## EQU1 ## Q = k × Va (k is a pipe shape factor)

In the present embodiment, it is arranged a plurality of flow sensors 12 ₁ to 12 ₄ in the gas passage, because it calculates the flow rate based on the average of these measurements, the difference in pipe shape Therefore, even if the flow velocity distribution changes, the flow velocity can be measured more accurately than a conventional flow meter having one flow velocity sensor. Therefore, the flow rate can be accurately measured over a wide range from a small flow rate to a large flow rate.

FIG. 4 is a perspective view showing a more specific embodiment of the flowmeter, FIG. 5 is a sectional view taken along the line BB of FIG. 4, and FIG. 6 is a direction taken along the line CC of FIG. FIG. 1 to 3 are denoted by the same reference numerals, and description thereof will be omitted.

In this flow meter, a guide member insertion portion 21 is provided at an arbitrary position on the wall surface along the longitudinal direction of the pipe 11 so as to penetrate the wall surface 11. A cylindrical guide member 22 is inserted into the guide member insertion portion 21. The guide member 22 is formed of a metal such as steel or a resin. The guide member 22 has a plurality of, for example, four first fluid passage holes 23 ₁ , 23 ₂ , 23 ₃ , 2 along the flow direction of the gas a at a portion inserted into the pipe 11.
3 ₄ is provided. Further, a plate-like partition portion 25 is provided along the longitudinal direction in the internal hollow portion of the guide member 22, and on both sides of the partition portion 25, as shown in FIG. 22b is provided. The partition 25 has four first fluid passage holes 23.
Similarly, four third fluid passage holes 26 ₁ , 26 ₂ , 26 ₃ , 26 ₄ are formed corresponding to ₁ , 23 ₂ , 23 ₃ , 23 ₄ .

[0023] The portion which is located outside of the pipe 11 of the guide member 22, along the first fluid passage holes 23 ₁ to 23 ₄ in the longitudinal direction (i.e. the direction of gas flow a), a plate-shaped indicator A part 24 is provided. After inserting the guide member 22 into the guide member insertion portion 21, look at the index portion 24,
A first fluid passage holes 23 ₁ to 23 ₄ can be accurately directed to the direction of gas flow a. Note that this positioning part 24
May be any as long as it can determine the installation direction of the guide member 22, and may be a mark display or the like.

The guide member 22 has a flow rate sensor unit 2
7 is inserted. The flow rate sensor unit 27 has a structure in which a columnar member formed of, for example, resin is divided into two, and the two semi-cylindrical unit members 27 are formed.
A, 27B. These unit members 2
7A, the 27B, the guide member first four formed 22 fluid passage hole 23 _{1-23 4} corresponding four second
Fluid passage hole 28 _1, 28 _2, 28 _3, 28 ₄ are formed. Of the two unit members 27A and 27B,
The unit member 27B located downstream with respect to the flow direction of the gas a has second fluid passage holes 28 ₁ , 28 ₂ , 28
_3, 28 ₄ flow sensor 29 ₁ so as to face each, 2
9 _2, 29 _3, 29 ₄ are disposed.

FIG. 7 shows the state of attachment of the flow velocity sensor unit 27 by taking out the guide member 22 and the flow velocity sensor unit 27. The unit insertion portion 22a of the guide member 22 has one unit member 27A constituting the flow rate sensor unit 27, and the unit insertion portion 22b has the other unit member 27 constituting the flow rate sensor unit 27.
B are inserted respectively.

In the present embodiment, a part of the gas a flowing through the pipe 11 is supplied to the _{four first} fluid passage holes 231 to 234 formed in the guide member 22 and the flow rate sensor unit 2.
Second fluid passage holes 28 ₁ to 28 ₄ formed on 7, and the third fluid passage holes 26 ₂₁ to formed in the partition portion 25
6 flow ₄ through the downstream side of the guide member 22, the flow rate is measured by the flow rate sensor 29 _{1-29 4} in the middle. The average value of the flow rate measured by the flow rate sensor 29 _{1-29 4,} obtained in the average flow velocity calculating unit 14 described above is converted into a further flow in the flow rate calculation unit 15, is displayed on the display unit 16. The rest of the gas a flows downstream on both sides of the guide member 22 along the outer wall surface of the guide member 22.

In this embodiment, the flow rate sensors 29 arranged at different positions on the same section in the pipe 11 are different from each other.
₁ for ~ 29 average of _four measurements is calculated, even if the flow velocity distribution is different due differences in pipe shape can be measured accurately velocity, thus accurately measure the flow rate over a wide range from a small flow rate to a large flow rate be able to. In this embodiment, since the outer shape of the guide member 22 is cylindrical, the gas a flows smoothly.

FIG. 8 is a perspective view showing still another embodiment of the flow meter, FIG. 9 is a sectional view taken along the line DD of FIG.
FIG. 10 is a view showing the state of attachment of the flow rate sensor unit 27 by taking out the guide member 22 and the flow rate sensor unit 27. FIG. 11 is a sectional view taken along the line EE of FIG.
FIG. 11 is a sectional view taken in the direction of arrows FF in FIG. 10. FIG.
6 are assigned the same reference numerals as in FIG. 6 and the description thereof is omitted.

In the present embodiment, two plate-like partitioning portions 25 are formed in the hollow portion inside the guide member 22 along the longitudinal direction.
A and B are formed, and unit insertion portions 22a, 22b, and 22c are provided with the partition portions 25A and 25B therebetween. Partitioning portion 25A, the first fluid passing hole 23 _{1-23 4} corresponding to the same four third fluid passage holes 26 ₁ to 26 ₄ which are formed in each guide member 22 to 25B
Are formed.

The flow rate sensor unit inserted into the guide member 22
The knit 27 has a structure in which a columnar member is divided into three.
And three columnar unit members 27A, 27B, 27C.
It is composed of These unit members 27A to 27
Each of the four C
1 fluid passage hole 23₁~ 23_FourFour second
Fluid passage hole 28₁~ 28_FourAre formed. Three you
Among the knit members 27A to 27C, the middle is in the flow direction.
The second fluid is supplied to the unit member 27C located in the central portion.
Passage hole 28₁, 28_Two, 28_Three, 28_FourFace each other
Flow sensor 29 ₁, 29_Two, 29_Three, 29_FourIs arranged
Have been.

As shown in FIG. 10, a unit member 27A is inserted into the unit insertion portion 22a of the guide member 22, a unit member 27B is inserted into the unit insertion portion 22b, and a unit member 27C is inserted into the unit insertion portion 22c. You.

In this embodiment, a part of the gas a flowing through the pipe 11 is
2, the four first fluid passage holes 23 ₁ to 23 2
3 _4, the second fluid passage holes 28 ₁ to 28 _4, and the partitioning portion 25A, the guide through the third fluid passage hole 26 _{1-26 4} formed in the B member 22 formed on the flow sensor unit 27 flows to the downstream side, the flow velocity is measured by the flow rate sensor 29 _{1-29 4} in the middle. The following is the same as the above embodiment.

[0033] Also in this embodiment, since the average of the respective different positions on the same cross-section arranged measured value of the flow velocity sensor 29 _{1-29 4} in the pipe 11 is calculated, it can be measured more accurately a flow rate Therefore, the flow rate can be accurately measured over a wide range from a small flow rate to a large flow rate. Further, in the present embodiment, the flow rate sensors 29 ₁ to 29 2
9 ₄ mounting is the unit member 27C is another unit member 27A for the sensor, since it is formed separately independently of the 27B, manufactured thin in structure such as a printed circuit board including the flow sensor 29 _{1-29 4} be able to.

FIG. 13 shows a configuration of a flow velocity sensor according to still another embodiment of the present invention. In this embodiment,
In this embodiment, two guide members 30 and 31 are further mounted in the horizontal direction on the flow meter shown in FIGS. The same components as those in FIGS. 4 to 7 are denoted by the same reference numerals, and description thereof will be omitted. Two first fluid passage holes 32 ₁ and 32 ₂ are formed in the guide member 30 and the flow rate sensor 3 similar to the flow rate sensor unit 27 is formed.
3 _1, 33 sensor unit including a ₂ is inserted. On the other hand, the sensor unit including a flow sensor unit 27 and the same flow rate sensor 35 _1, 35 ₂ with the first fluid passage hole 34 ₁ is also of the two guide member 31, 34 ₂ is formed is inserted.

In this embodiment, the guide member 22
The guide members 30 and 31 are disposed so as to be orthogonal to each other, and the eight flow velocity sensors 2 are larger in number than in the above embodiment.
9 _{1-29 4,} 33 _1, 33 _2, 35 _1, 35 the average of the _two measurements is calculated more accurately be measured the flow velocity, it is possible to accurately measure the flow rate over a wider flow range .

In the above embodiment, the guide member 22
And the guide members 30 and 31 are disposed so as to be orthogonal to each other. However, as shown in FIG.
Guide members 36 and 37 having the same structure as 1 are further added, and each member is configured to form an angle of 60 ° with each other. By further increasing the number of flow velocity sensors, the flow velocity can be measured more accurately. The flow rate can be accurately measured over a wider flow rate range.

The present invention is not limited to the above embodiment. For example, in the embodiment shown in FIGS. 13 and 14, a plurality of fluid passage holes and a plurality of Is provided, but one fluid passage hole and one flow sensor may be provided for each guide member and flow sensor unit. In short, a plurality of fluid passage holes and a plurality of What is necessary is just a structure in which a flow velocity sensor is arranged. In each of the above embodiments, the guide member 22 is inserted into the boss (guide member insertion portion 21). However, as shown in FIG. 40,
41 may be provided, and both may be fixed by tightening screws 42, 43. Further, an O-ring may be interposed between the pipe 11 and the guide member 22 to prevent gas leakage.

[0038]

As described above, according to the flow meter according to any one of the first to sixth aspects, a plurality of flow rate sensors are disposed in the fluid flow path in the pipe, and the measured values of the flow rate sensors are measured. it is possible to convert the flow rate to determine the average value, and improve the measurement accuracy, there is an effect that a wide range of flow rates can be measured accurately.

[Brief description of the drawings]

FIG. 1 is a sectional view illustrating a configuration of a flow meter according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1;

FIG. 3 is a block diagram illustrating a circuit configuration of the flow meter of FIG.

FIG. 4 is a perspective view illustrating a specific mode of the flow meter of FIG.

FIG. 5 is a sectional view taken along line BB of FIG. 4;

6 is a cross-sectional view taken along line CC of FIG.

FIG. 7 is an exploded perspective view showing a guide member and a flow rate sensor unit of the flow meter of FIG.

FIG. 8 is a perspective view illustrating a configuration of a flow meter according to another embodiment of the present invention.

FIG. 9 is a cross-sectional view taken along line DD of FIG. 8;

FIG. 10 is an exploded perspective view showing a guide member and a flow rate sensor unit of the flow meter of FIG.

FIG. 11 is a front view in the direction of arrows EE in FIG. 10;

FIG. 12 is a front view in the direction of arrows FF in FIG. 10;

FIG. 13 is a cross-sectional view illustrating a configuration of a flow meter according to still another embodiment of the present invention.

FIG. 14 is a sectional view illustrating a configuration of a flow meter according to still another embodiment of the present invention.

FIG. 15 is a sectional view illustrating a configuration of a flow meter according to still another embodiment of the present invention.

FIG. 16 is a cross-sectional view for explaining a measurement principle of a conventional flow meter.

FIG. 17 is a sectional view taken along line GG of FIG. 16;

[Explanation of symbols]

Reference Signs List 11 piping 12 _{1 to} 12 ₄ , 29 _{1 to} 29 ₄ flow rate sensor 13, 22 guide member 13 _{1 to} 13 ₄ fluid passage hole 14 average flow rate calculating section 15 flow rate calculating section 16 display section 21 guide member inserting section 23 ₁ to 23 ₄ First fluid passage hole 24 Positioning unit 26 _{1 to} 26 ₄ Third fluid passage hole 27 Flow rate sensor unit 27A, 27B, 27C Unit member 28 _{1 to} 28 ₄ Second fluid passage hole

Claims (6)

(57) [Claims] A guide member insertion portion provided at an arbitrary position on a wall surface along a longitudinal direction of the pipe so as to penetrate the wall surface, and inserted into the pipe via the guide member insertion portion; A hollow guide member having a plurality of first fluid passage holes along a flow direction of the fluid; a plurality of guide members being inserted into the guide member and corresponding to the plurality of first fluid passage holes of the guide member; A flow rate sensor unit having a second fluid passage hole and a plurality of flow rate sensors arranged so as to face each of the plurality of second fluid passage holes; Average flow velocity calculating means for receiving each output signal as input and calculating an average value of flow velocity at a plurality of points in the fluid flow path; flow rate calculating for calculating a flow rate of the fluid based on a calculation result of the average flow rate calculating means Flowmeter characterized by comprising a stage. 2. A plurality of guide member insertion portions provided so as to penetrate the wall surface on the same cross section orthogonal to the longitudinal direction of the pipe, and each of the guide member insertion portions is inserted into the pipe via these guide member insertion portions. And a plurality of hollow guide members having at least one first fluid passage hole along the flow direction of the fluid, and inserted into each of these guide members and the first fluid passage of the guide member At least one corresponding to the hole
A plurality of flow rate sensor units each having two second fluid passage holes and at least one flow rate sensor disposed so as to face the second fluid passage holes; and a plurality of flow rate sensors in these flow rate sensor units. And an average flow velocity calculating means for calculating an average value of flow velocity at a plurality of points in the fluid flow path, and a flow rate for calculating a flow rate of the fluid based on a calculation result of the average flow velocity calculating means. A flow meter, comprising: a calculation unit. 3. The flowmeter according to claim 2, wherein the guide member is formed in a cylindrical shape. 4. The guide member has one partition in which at least one third fluid passage hole corresponding to the first fluid passage hole is formed in the inner hollow portion along the longitudinal direction. And a semi-cylindrical unit insertion part on each side of the partition part. On the other hand, the flow rate sensor unit is formed of two semi-cylindrical unit members each insertable into the unit insertion part of the guide member. Each of these unit members is provided with at least one second fluid passage hole facing the third fluid passage hole, and corresponds to the second fluid passage hole on the unit member side arranged downstream. 4. The flowmeter according to claim 3, further comprising a flow rate sensor. 5. The guide member has two partition portions in which at least one third fluid passage hole is formed in the inner hollow portion along the longitudinal direction corresponding to the first fluid passage hole. And three unit insertion portions with these partition portions interposed therebetween. On the other hand, the flow rate sensor unit includes three unit members that can be inserted into the unit insertion portions of the guide members, respectively. At least one second fluid passage hole is provided opposite to the third fluid passage hole, and the flow velocity corresponds to the second fluid passage hole of the unit member disposed at the center in the flow direction. 4. The flow meter according to claim 3 , wherein a sensor is provided. 6. Corresponding to the first fluid passing hole to the outer wall of the guide member, with claim 1, characterized in that it comprises an indicator portion for matching the installation direction of the guide member 5 1 The flow meter according to one of the above.