JPS6212255Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is based on the Karman vortex flowmeter, which enables easy and highly accurate measurement of flow rates over a large range by appropriately replacing and combining the vortex flowmeter body and the separate mounting plate. Regarding vortex flow meter unit.

In general, a flowmeter known as a Karman vortex flowmeter detects and counts the Karman vortices that are generated alternately on the downstream side of a vortex generator installed in a pipe through which the fluid flows. Therefore, it is assumed that the size of the pipe cross section is suitable for the vortex generation effect, or that the vortex detection and counting effects are excellent, etc., will have a large impact on improving flow accuracy. It is said.

In particular, when the flow rate of the fluid to be measured becomes large, the entire flowmeter has to be enlarged, which not only becomes expensive, but also requires greater precision in order to improve accuracy, which poses a big problem in terms of cost. It's summery.

As a solution to this problem, the present applicant has previously proposed a vortex flowmeter equipped with a branch pipe as shown in FIG. 1, for example.

That is, the Karman vortex flow rate is such that the overall flow rate can be measured by installing a branch line 4 in the main line 3 in which the vortex generator 1 and the vortex detection mechanism 2 are provided, and measuring the flow rate flowing through the main line 3. This is related to the total amount. If the cross-sectional area of the shunt 4 in this case is appropriately selected, the flow rate of the main pipe 3 can be maintained at the optimum conditions for measurement.

However, in the past, the main pipe line 3 was used as a fixed set with the shunt line 4 fixed and attached as one unit, so there were several types of sets in which the main pipe line and the shunt line were appropriately combined according to the flow rate range. It is necessary to prepare the same, leading to an increase in costs in terms of productivity and inventory management, and there are problems in that it tends to be difficult to respond quickly to demand. Furthermore, even if the main pipe and branch pipe (bypass pipe) are appropriately combined according to the flow rate range, fine adjustment of the flow rate may be necessary within the specified range, but this cannot be easily done. was difficult.

This idea was made with attention to these problems, and its purpose is to provide a vortex flowmeter body equipped with a vortex detector, a vortex flowmeter body that can be detachably attached, and a vortex flowmeter body equipped with a vortex detector. Various types of mounting plates, each of which is provided with a diversion bypass pipe having various diameters as necessary, are formed separately, and the desired mounting plates are appropriately selected and assembled to the vortex flowmeter main body. Accordingly, it is an object of the present invention to provide a vortex flow meter unit that can be installed in a manner that is well adapted to the dimensions and flow rate of a system through which a fluid to be measured flows, and can easily obtain optimum measurement conditions.

Another object of the present invention is to pre-drill a hole in the mounting plate for fine flow adjustment that can be opened and closed with a plug, and to adjust the degree of opening by simply attaching and removing the plug. To provide a vortex flowmeter unit which prevents a stopper from falling out of a hole due to fluid pressure or other mechanical vibrations, and which allows easy and precise adjustment of the flow rate within a desired optimum flow rate range to measure the flow rate.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

First, the configuration will be explained. In FIG. 2, 11 is the vortex flow meter main body, and 12 is a separately formed mounting plate. The vortex flow meter main body 11 includes a vortex generating body 1 having a triangular cross section or the like, which is provided facing the flow in a straight cylinder portion 13 having a rectangular cross section perpendicular to the flow direction of the fluid.
4 and an ultrasonic transmitter 15a and an ultrasonic receiver 1 provided opposite to each other on the side wall of the straight cylindrical portion 13 on the downstream side thereof.
5b is provided.

However, the vortex generator 14 is not limited to the one shown in the drawings, for example, as described in Japanese Patent Application No.
A vortex generator having multiple configurations as shown in No. 139020 may also be used.

Further, the vortex detection mechanism 5 can also have various mechanisms such as a strain gauge configuration, a diaphragm configuration, a configuration utilizing temperature change, an electrical configuration, etc. in addition to the configuration using ultrasonic waves.

Reference numeral 16 denotes a collar that is integrally formed at the downstream end of the straight cylindrical portion 13 and is formed to protrude from the mounting holes 16a, 16.
b, 16c, and 16d are provided.

Incidentally, reference numeral 17 denotes an arc-shaped possible constriction section 1, such as a nozzle, which is connected to the front part of the straight cylindrical section 13 and gradually expands.
An enlarged cylindrical part with a square cross section provided at the tip of 7.
A rectifier 19 having a honeycomb structure, for example, is provided over the entire area.

Reference numeral 20 indicates an ultrasonic sound-absorbing material such as a non-woven fabric attached along the inner wall surface of the vortex flowmeter main body 11 over the entire area or at necessary locations to improve the accuracy of the vortex detection mechanism 15.

Therefore, the vortex flowmeter body 11 shown in the above-described embodiments is not necessarily limited in all its configurations, and its cross-sectional shape, rectifier 19,
The presence or absence of the retractable portion 17 can be changed or selected as appropriate. On the other hand, the mounting plate 12 has, for example, a disc-shaped outer shape, and its plane part 21 has a shape and depth that match the flange 16 formed at the end of the vortex flowmeter main body 11. Fitting recess 2
2, and the mounting holes 16a, 16b, 1 of the collar 16
Mounting holes 22a drilled corresponding to 6c and 16d,
22b, 22c, 22d, and further the straight cylindrical portion 1
A mounting mechanism A consisting of a through hole 23 bored corresponding to 3 is provided.

The center of the through hole 23 is offset from the center of the mounting plate 12, thereby ensuring a space for providing a bypass conduit, which will be described later, on the mounting plate 12. Further, a sealing mechanism B having a sealing material mounting groove 24 is provided on the outer periphery of the mounting plate 12. The sealing mechanism B may be provided on the outer flat surface of the mounting plate 12. Furthermore, a flow rate fine adjustment hole 25 having a counterbore 25a as shown in cross section in FIG. 6 is bored in the flat surface 21 of the mounting plate 12. By attaching and detaching a plug 26 to and from this hole 25, it is possible to finely adjust the bypass flow rate of the vortex flow meter main body.

The diameter and number of the fine adjustment holes 25 are selected as appropriate; for example, in the example shown in FIG. Each small hole is formed so that the bypass flow rate of the fluid can be adjusted to 0.5%.

3 and 4 show a mounting plate 12a integrally provided with one bypass conduit 27, and FIG. 5 shows a mounting plate 12b integrally provided with two bypass conduits 28, 28. These bypass lines 27 or 2
The number, shape, cross-sectional area, and length of 8 and 28 may be freely selected as necessary and within the space available.

The above-mentioned mounting plates 12, 12a, 12b can be selected, for example, as shown by the chain line in FIG.
By assembling it into the vortex flowmeter main body 11, a vortex flowmeter unit 33 is constructed. In other words, in the figure, 3
0 is the mounting hole 16a, 16b, 16c, 16d and the corresponding mounting hole 22a, 22b, 22c, 22d
The vortex flow meter unit 33 assembled in this way is installed in the pipe line 32 via a sealing material 31 such as an O-ring, for example. In addition, although the above-mentioned Example showed the case where the number of bypass pipes differed, it is needless to say that it is not limited to this, and the diameters of the bypass pipes may be different.

The vortex flowmeter unit 33 of the present invention constructed as described above is used in the manner shown in FIG. That is, (a) shows the case where the device is installed at the end of the pipe 32 through which the fluid to be measured flows, and the fluid is sucked downstream and flows. (b) shows the case where the tube is mounted in a pinched manner in the divided piping 32, and the fluid is forced to flow from the upstream side. In this case, the vortex flow meter unit 3
It is attached via the upstream flange 34 of No. 3. (C) shows the case where it is installed in the middle of the pipe 32, and the vortex flow meter unit 33 may be installed at a predetermined position in the pipe 32 and inserted so as to be locked to a stepped portion (not shown).

The operation of the present invention will be explained based on the above configuration.

When the vortex flowmeter main body 11 is combined with the mounting plate 12 having no bypass pipe line, the entire amount of fluid flowing through the pipe 32 passes through the vortex flowmeter main body 11 and is detected by the vortex generator 14 and the vortex detection mechanism 15. The flow rate is sensed and measured. On the other hand, the mounting plate 12a or 12 having the bypass line 27 or 28, 28
In the case of combining b, the fluid flowing through the pipe 32 is divided by the vortex flow meter main body 11 and the bypass pipe 27 or 28, and the fluid flowing inside the bypass pipe 27 or 28 flows as it is without being measured. . On the other hand, the flow rate of the fluid flowing inside the vortex flow meter main body 11 is detected and measured, and as a result, both pipes 11
and 27 or 28 can be measured.

Therefore, the size of the flow path, especially when the flow rate is large,
In order to structurally fix only the vortex flowmeter main body 11, which serves as a measurement pipe, and adjust the flow rate by adjusting the size of the branch pipe attached to this, bypass pipes 27 or 27 having various diameters are used. Mounting plate 12a provided with 28
Alternatively, only the configuration of 12b may be appropriately selected according to the flow rate and installed in combination with the vortex flow meter main body 11.

Next, the function of the flow rate fine adjustment holes 25 formed in the mounting plates 12, 12a, and 12b will be explained.

This hole 25 is normally left open, so that a portion of the fluid flowing through the pipe 32 is diverted and passes through this hole 25 . By the way, the vortex flowmeter body 11
Since the ratio of the flow rate Q to a unit pulse of the fluid to be measured flowing therein (meter coefficient) is approximately constant within a certain fixed flow rate range, a flow rate larger than this certain range flows inside the vortex flowmeter body 11. In some cases, it is necessary to control the amount of bypass so that the flow rate can be maintained within the above-mentioned certain range.

In that case, the fine adjustment hole 25 may be closed with the plug 26. As a result, the flow rate inside the vortex flowmeter main body 11 can be adjusted to 0.5%, 1%, 1.5% of the total flow rate, for example.
It can be increased or decreased in steps such as 2%, 2.5%, and 3%. In this case, the head of the stopper 26 is attached to the mounting plate 1.
2, it is possible to prevent the risk of the plug 26 being washed away downstream due to fluid pressure or the like.

After the plug 26 is inserted, the countersunk portion 25a prevents it from coming off in the opposite direction.

As explained above, according to this invention, the configuration of the vortex flowmeter unit is such that the vortex flowmeter body is equipped with a vortex generator and a vortex detection mechanism, and the vortex flowmeter body can be detachably attached, and the vortex flowmeter unit can be removably attached. Just by separately forming mounting plates that are also provided with diversion bypass pipes having various diameters depending on the flowmeter, and selecting and assembling the desired mounting plates to the vortex flowmeter main body, Since it can be installed according to the dimensions and flow rate of the system through which the fluid to be measured flows, various types of flowmeters with different flow rate ranges can be easily installed by simply installing the main body in the specified position on the mounting plate. Moreover, it can be obtained at a low cost and has the effect of being able to respond immediately to demand. Furthermore, since the mounting plate has a hole for fine flow adjustment that can be opened and closed with a plug, flow control to maintain proper measurement conditions can be easily performed on site, making it possible to freely measure flow with high precision. is obtained. Furthermore, since the plug is shaped so that it does not easily fall off from the flow rate fine adjustment hole, there is also the effect that stable flow rate measurement can be performed.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a conventional vortex flowmeter equipped with a branch pipe, Fig. 2 is a perspective view showing the main parts of an embodiment of this invention, and Fig. 3 is a mounting plate of this invention. Fig. 4 is a front view showing an example of - of Fig. 3.
An explanatory diagram showing a line cross section, FIG. 5 is a front view showing another example of the mounting plate according to this invention, and FIG. 6 is a diagram showing FIG.
The line sectional view and FIG. 7 are explanatory diagrams showing the usage mode. 1, 14... Vortex generator, 2, 15... Vortex detection mechanism, 11... Vortex flowmeter body, 12, 12a, 12
b...Mounting plate, 21...Plane part, 25...Flow rate fine adjustment hole, 27, 28...Bypass pipe line, 33...
...Vortex flow meter unit, A...Mounting mechanism, B...Seal mechanism.

Claims (1)

[Claims for Utility Model Registration] (1) A vortex flowmeter body provided with a vortex generator and a vortex detection mechanism, a collar integrally formed at the downstream end of the vortex flowmeter body, and A mounting plate having a recess for fixation is formed, a bypass pipe is provided on the mounting plate, a sealing mechanism is provided on the mounting plate to fit into the pipe through which the fluid to be measured flows, and the mounting plate has different sizes. A vortex flowmeter unit characterized by having a hole drilled therein and a plug for closing the hole being detachably provided. (2) The vortex flowmeter unit according to claim 1, wherein the hole has a counterbore. (3) The vortex flowmeter unit according to claim 1, wherein the plug has a head and a shape to prevent it from coming off.