JPS60164217A - Flow rate detecting device - Google Patents

Abstract

PURPOSE:To make flow-rate resistance very small, by providing linear blades at the blade tip parts of the first curved blade, which axially turns a fluid to be detected, and the second curved blade, which is provided at a downstream position in a 180 deg. point symmetrical manner with respect to the first curved blade. CONSTITUTION:A blade tip part 13 of an arc blade 11, which is the first curved blade that axially turns a fluid to be detected, is constituted of a linear blade, which is approximately in parallel with respect to an arrow 14 indicating the flowing direction in a flow path. An arc blade 16, which is the second curved blade, is provided in a 180 deg. point symmetrical manner with respect to the blade 11 at the downstream from a magnetic ball 15. A blade tip part 17 of the blade 16 is also formed by a linear blade which is approximately in parallel with the flowing direction 14. When the fluid to be detected flows in from the direction of the arrow 14, the fluid to be detected is aligned by the linear blade of the blade tip part 13 and flows along the arc blade 11. Thus the fluid is axially turned. As a result, a magnetic ball 15 placed in the turning flow is turned in a vertical plane with respect to the flow direction 14. The number of turning of the ball 15 is proportional to the flow rate. Therefore, by counting the number of turning of the ball 15, the flow rate can be measured.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a flow rate detection device for measuring the flow rate of fluid.

Structure of the conventional example and its problems A conventional flow rate detection device of this type has a structure as shown in FIGS. 1 and 2. In FIGS. 1 and 2, reference numeral 1 denotes an annular flow path having a circular cross section, and an inflow path 2 and an outflow path 3 are opened at the outer periphery of this flow path. This inflow passage 2 is provided with a nozzle 4 . Further, a sphere 5 is inserted into the annular flow path 1, transparent windows 6 and 7 are formed, and a light emitting element 8 and a light receiving element 9 are provided. In such a configuration, when fluid enters the annular channel 1 from the nozzle 4 of the inflow channel 2, the flow flows from the inflow channel 2 to the outflow channel 3 while circulating in the annular channel 1, and the sphere 5 also flows along with it. It moves around inside the annular flow path 1 in the direction of the solid arrow. Since the rotational speed of the sphere is proportional to the flow rate of the fluid, the rotational speed of the sphere 5 is detected as a pulse signal by the light emitting element 8 and the light receiving element 9, and the flow rate is measured through the control circuit.

The first problem with this conventional example is that the flow resistance is large. Since the annular flow path 1 is formed, the inlet and outlet of the flow path change direction, resulting in bending loss, and the circular flow intersects with the flow from the inflow path 2 near the inflow path, resulting in inflow resistance and loss. arise. Furthermore, if the sphere is configured to have a size close to the cross-sectional area of the annular flow path 1 so as to promote the rotation of the sphere 5, a large flow resistance will occur.

Further, if a nozzle 4 is provided in the inflow passage 2 so that the sphere 5 circulates smoothly, the flow passage resistance becomes even greater.

Second, there is the second problem of configuration, such as the fact that the sensor structure tends to be large. 2, the passage resistance increases, so it is necessary to increase the passage diameter to reduce it, and since it has an annular passage 1, it requires more space than a straight pipe. Yes, the sensor as a whole is larger than the front and rear passages. In addition, the inflow passage 2 and the outflow passage a
The direction of the sensor is limited to some extent, which poses problems such as constraints on the structure when incorporating it into equipment as a sensor, and an increase in overall size.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a small and compact flow rate detection device that eliminates such conventional drawbacks and has low flow resistance.

Structure of the Invention In order to achieve this object, the present invention includes a first curved blade that swirls the fluid to be detected in an axial flow, a rotating body that revolves in this swirling flow, and a first curved wing that is located downstream of this rotating body. It consists of a second curved wing provided 180 degrees symmetrically with respect to the first curved wing, and a detection means for detecting the rotational speed of the rotating body, and the blade tip of at least one of the curved wings is connected to a straight wing. This is what I did. With this configuration, the fluid to be detected is swirled in an axial flow, and in this swirling flow, it goes around a rotating body whose area is smaller than the cross-sectional area of the flow path, and the fluid to be detected is rectified by the straight blades, resulting in an extremely small flow rate. A small and compact flow rate detection device having resistance can be obtained.

DESCRIPTION OF EMBODIMENTS Next, embodiments of the present invention will be described with reference to FIGS. 3 and 4. In FIG. 3, reference numeral 10 denotes a housing, and inside the housing 10 are fixed to a casing 12 arcuate blades 11, which are first curved blades for axially swirling the fluid to be detected. The blade tip portion 13 of the arcuate blade 11 is constituted by a straight blade substantially parallel to an arrow 14 indicating the flow direction in the flow path. A magnetic sphere 15, which is a rotary body, is provided downstream of the arcuate blade 11 and rotates in a plane perpendicular to the flow direction and has a diameter much smaller than the cross-sectional area of the flow path. This magnetic sphere,
15 configurations include steel balls, hollow steel balls, and resin balls that are magnetically plated and then resin molded. A circular arc blade 1, which is a second curved blade, is downstream of the magnetic sphere 15.
6 is provided 180 degrees symmetrically with the first arcuate blade 11. The blade tip 17 of the second arcuate blade 16 on the opposite side to the circumferential surface of the magnetic sphere 15 also has an arrow 1 indicating the flow direction in the flow path.
It consists of straight wings that are approximately parallel to the 4.

The casing 12 is inserted into the housing 10 and fixed by a C-ring 18. Also, on the outside of the housing 10, there is a permanent magnet 19 and a magnetic resistance element 2 which is a magnetic detection element.
A rotation detector 21, which is a detection means for detecting the number of rotations of the magnetic sphere 15, is provided to constitute a flow rate detection device.

22 and 23 are piping connection ports, and 24 is an arrow indicating the direction of rotation of the magnetic sphere 15.

FIG. 4 is a diagram showing a state in which the inflow direction of the fluid to be detected is opposite to that in FIG. 3 as indicated by an arrow 25, but the configuration is the same as that in FIG. 3, and a description thereof will be omitted.

The operation of the above configuration will be explained with reference to FIG. Third
In the figure, when the fluid to be detected flows in from the direction of the arrow 14, the fluid to be detected is rectified by the straight blades of the blade tips 13, and then flows along the arcuate blades 11, thereby causing an axial swirl. As a result, the magnetic sphere 15 placed in the swirling flow gains a kinetic force from the swirling flow and rotates in a plane perpendicular to the direction of the flow shown by the arrow 14. The fluid to be detected that has passed the position of the magnetic sphere 15 flows along the arcuate blade 16 and then reaches the blade tip 17.
It is rectified by the straight blades and flows in the direction of the piping connection port 23.

The flow rectified by the straight blade is not a swirling flow, but as shown by arrow 1.
The flow is almost the same as direction 4.

Since the number of rotations of the magnetic sphere 15 is proportional to the flow rate, the flow rate can be measured by measuring the number of rotations of the magnetic sphere 15. As a method, a magnetic field of a constant strength is applied to the magnetoresistive element 20 by a permanent magnet 19, and the change in resistance of the magnetoresistive element 20 when the magnetic sphere 15 passes through this magnetic field is extracted as a pulse change in voltage. The measurement is performed via a control circuit (not shown).

FIG. 4 is a diagram when the inflow direction of the fluid to be detected is in the direction of the arrow 25. In this case, the fluid to be detected is axially swirled by the arcuate blades 16, and the magnetic sphere 15 The direction of rotation is the direction of arrow 24. The operation is the same as that shown in FIG. 3, and the explanation will be omitted.

In this embodiment, since the curved blades are configured with circular arc blades, the loss when the fluid to be detected is swirled in an axial flow is reduced. Furthermore, since the rotating body is detected by a magnetic sensor, the rotation can be detected from outside the housing, and even if the fluid to be detected is opaque, it has the advantage of being able to detect it.

Effects of the Invention As is clear from the above explanation, the flow rate detection device of the present invention includes a first swirling vane that axially swirls the fluid to be detected flowing in a flow path, and a first swirling vane that is located in this swirling flow in the direction of the flow. a rotating body rotating in a plane perpendicular to the rotating body, and a second curved blade located downstream of the rotating body and provided 180 degrees symmetrically with respect to the first curved blade.
and a detecting means for detecting the rotational speed of the rotating body, and a blade end portion of at least one curved blade on the side opposite to the rotating body circumferential surface is configured to detect a fluid to be detected flowing in the flow path. The following effects can be obtained by arranging the elements substantially parallel to each other.

(1) Low flow resistance. The fluid to be detected is axially swirled, and the rotating body is also configured to have a smaller diameter than the cross-sectional area of the flow path. Furthermore, in comparison with conventional ball-type flow rate sensors, the flow resistance of the fluid is extremely small, as there is no extreme change in the flow path and no interference with the fluid itself.

(2) The structure of the flow rate detection device is small and compact.

Unlike those in which the flow path itself forms an annular flow path, this type has the feature that it creates an axial flow swirl in the straight pipe section and circulates around a rotating body, and the flow path structure is the simplest and can be constructed with a short flow path length. .

(3) Flow rate measurement is possible regardless of the flow direction of the fluid to be detected. , a rotating body is provided downstream of the first curved blade, and a second curved blade is provided downstream of the rotating body in point symmetry with respect to the first curved blade, thereby detecting the fluid to be detected.

It becomes possible to measure the flow in two directions. Furthermore, by configuring at least one of the curved blades on the opposite side of the rotating body circumferential surface as a straight blade that is substantially parallel to the fluid to be detected, the flow before and after the curved blade is rectified and loss is reduced. It has the effect of making it smaller.

Note that the present invention is not limited to the above configuration, but the first
The curved wing and the second curved wing may be integrally constructed.

[Brief explanation of drawings]

FIG. 1 is a horizontal sectional view of the flow path of a conventional flow rate detection device, FIG. 2 is a vertical sectional view of the same device, and FIGS. 3 and 4 are cross sections of a flow rate detection device each showing an embodiment of the present invention. It is a diagram. 11...First curved wing (arc wing), 13...
... Wing tip (straight wing), 15... Rotating body (magnetic sphere), 16... Second curved wing (arc wing),
17... Wing tip (straight wing), 21...
Detection means (rotation detector). Name of agent: Patent attorney Toshio Nakao (1st person)
Figure 3 Figure 2 Figure 3 Figure 9 Figure 4

Claims (3)

[Claims] (1) A first system that rotates the detected fluid flowing in the flow path in an axial flow.
a curved blade, a rotating body located in the swirling flow and rotating in a plane perpendicular to the flow direction, and a rotating body located downstream of the rotating body and 180 degrees symmetrical with respect to the first curved blade. It comprises a second curved blade provided and a detection means for detecting the orbiting rotation speed of the rotating body, and a blade end portion of at least one curved blade on the opposite side to the rotating body circumferential surface flows in the flow path. A flow rate detection device consisting of straight blades that are almost parallel to the fluid to be detected. (2) The flow rate detection device according to claim 1, wherein the curved blade is an arcuate blade. (3) The flow rate detection device according to claim 1, comprising a detection means in which the rotating body is a magnetic sphere and is detected by a magnetic sensor.