JPS6210649Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a vortex flowmeter that can measure flow rate with high sensitivity.

Vortex flowmeters have been put into practical use in the past, in which a flexible vortex generator is placed in the flow path and the flow rate is measured by detecting the flexible deformation of the vortex generator. Vortex flowmeters have the disadvantage of not being highly sensitive. Conventionally, such a vortex flowmeter that has been put into practical use fixes one end of the vortex generator to a conduit and protrudes the other end into the flow path to flexibly deform using the fixed surface as a fulcrum. The body needs to have a relatively large cross-sectional area in order to generate Karman vortices, and in order to maintain its shape, a material with a fairly high Young's modulus must be used, resulting in Karman vortices. The displacement of the vortex generator, that is, the sensitivity to

This idea was devised by focusing on the above-mentioned problems with vortex flowmeters, and its purpose was to reduce the section modulus of the vortex generator by providing a notch in the vortex generator. By embedding a material with a lower Young's modulus than the vortex generator in the notch and restoring the shape of the vortex generator to its original state without the notch, it is possible to measure the flow rate with high sensitivity without deteriorating measurement accuracy. The object of the present invention is to provide a vortex flow meter that can measure .

An embodiment of this invention will be described below with reference to the drawings.

The figure shows a part of the vortex generator that constitutes the main part of the vortex flowmeter. In the figure, 1 is a vortex generator formed in the shape of a triangular prism, and one end of the vortex generator is connected to a pipe wall (not shown).
The other end is configured to protrude into the flow path and generate a Karman vortex. Further, the vortex generator 1 is made of a desired flexibly deformable material such as metal or resin, and is configured to be flexibly deformable in response to pressure changes caused by generation of vortices. 2 is a concave portion formed near the center of the vortex generating body 1; 3 is a concave portion having one end fixed to the concave portion 2 and the other end connected to a desired fixed object (not shown) located outside the vortex generating body 1; The fixed plate 4 is a strain detector mounted on the fixed plate 3, and is made of a member such as a strain gauge, so as to be able to detect the flexible deformation of the vortex generating body 1. This vortex generator 1 is arranged so that its surface A faces the flow direction B in the flow path.
When viewed from the direction B, slits 5, 5 are provided which are horizontally cut out from both left and right ends toward the center. Furthermore, filling members 6 made of a material such as resin or metal having a smaller Young's modulus than the vortex generator 1 are embedded in the slits 5, 5, respectively, and grooves 7, which are formed in the slits 5, 5, respectively, are embedded therein. 7 locks the filling member 6 to prevent it from falling off from the vortex generator 1. Furthermore, this filling member 6 completely fills the slits 5, 5 of the vortex generator 1, and the shape of the vortex generator 1 is such that the slits 5, 5,
5, it has a triangular prism shape with a uniform plane.

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

If the vortex generator 1 is disposed in a desired flow path to be measured, and the open end 3a of the fixed plate 3 is fixed to the desired path, and the output of the strain detector 4 is measured, as is known in the art. A Karman vortex is generated near the vortex generator 1, and the vortex generator 1 is flexibly deformed due to the pressure change caused by the generation of the Karman vortex, so this displacement is detected as strain by the strain detector 4, and the Karman vortex is A corresponding output is obtained, namely the flow rate or flow rate.
Here, the vortex generator 1 flexibly deforms due to pressure fluctuations, and the vortex generator 1 is provided with slits 5, 5, in which filler members 6, 6 with a small Young's modulus are embedded. Therefore, assuming that the Young's modulus of the filling members 6, 6 is negligibly small compared to that of the vortex generator 1, the section modulus of the vortex generator 1 becomes extremely small due to the slits 5, 5. High sensitivity can be achieved.

Further, since the slits 5, 5 are completely filled with the filling member 6, they do not affect the Karman vortex, and the measurement accuracy does not deteriorate.

Note that the shape of the vortex generator and the shape and position of the slit are not particularly limited, and the same applies to the mounting position of the strain detector and the support type of the fixed plate.

FIG. 3 shows an embodiment in which the vortex generator 1' is supported at both ends. One end of the vortex generator 1' is fixed to the conduit by its flange, and the other end is fixed to the conduit by a flat spring C or the like. It is temporarily fixed by being supported within the conduit via a flexible body. By adopting such a structure in which both ends are supported, earthquake resistance, which is a drawback of vortex flowmeters, can be improved.

According to this invention, the vortex generator has the same vortex generation ability as before, but its section modulus is reduced, making it easier to displace the vortex generator, making it possible to measure flow with high sensitivity. An extremely reliable vortex flowmeter can be obtained because there is no deterioration in characteristics.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the vortex generator of the vortex flow meter according to this invention, and FIG. 2 is the same as that shown in FIG.
FIG. 3 is a cross-sectional view showing an embodiment in which the vortex generator is supported at both ends. 1, 1'... Vortex generator, 2... Concave portion, 4...
Strain detector, 5... slit, 6... filling member.

Claims (1)

[Claims for Utility Model Registration] (1) In a vortex flowmeter in which a vortex generator is disposed in a flow path and the flow rate is measured using the deformation of the vortex generator due to vortex fluctuation pressure, A minute width slit is provided from both ends of the generator in a direction perpendicular to the axis.
The cross-section of the vortex generator sandwiched between the slits is approximately rectangular, and a filling member having a Young's modulus smaller than that of the vortex generator is buried in the slit to detect strain in the vicinity of the rectangular cross-section of the vortex generator. Features of vortex flowmeter. (2) The vortex flowmeter according to claim (1) of the utility model registration, characterized in that the slit has a groove larger than the slit width bored in parallel with the slit and a filler embedded therein. .