JPS603519A - Flow rate detecting device - Google Patents

Abstract

PURPOSE:To obtain an extremely small flow rate resistance, and also to obtain a small- sized and compact flow rate detecting device by setting a flow direction of a fluid to an axial-flow direction, and rotating a rotating body whose area is smaller than a sectional area of a flow path in a swirling flow by a swirling means. CONSTITUTION:A fluid to be detected which has flowed in from an inlet 24 side is brought to axial-flow swirling by flowing to the downstream along a circular arc blade 13 of a blade 11. As a result, a magnetic spherical body 18 turns round in the direction vertical to a direction of the flow by obtaining a dynamic force by the swirling flow. In this case, the magnetic spherical body 18 abuts on two points of a rotating surface 28 of a spherical body receiver 19 and a casing 12 and turns round. A revolving speed of a rotation of this magnetic spherical body 18 is proportional to a flow rate, therefore, the flow rate can be measured by measuring the revolving speed of this magnetic spherical body 18. Its means gives a magnetic field of a constant strength to a magneto-resistance element 21 by a permanent magnet 20, and a resistance variation of the magneto-resistance element 21 in case when the magnetic spherical body 18 has passed through this magnetic field is fetched as a pulse variation of voltage, and processed through a controlling circuit.

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.

2.-2゛Conventional structure and problems thereof Conventionally, this type of flow rate detection device has been structured 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, a transparent window 6.7 is formed, and a light emitting element 8 and a light receiving element 9 are provided. In this 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. This results in losses. 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 50 revolutions of the sphere, a large flow path resistance will occur. Further, if a nozzle (V4) is provided in the inflow passage 2 so as to make the rotation of the sphere 5 smooth, the flow passage resistance becomes even greater. Second, there are structural issues such as the sensor structure tends to be large. As mentioned above, the passage resistance increases, so it is necessary to increase the passage diameter to reduce it.Also, since it has an annular passage 1 compared to a straight pipe, a corresponding amount of Nupaine is required. The sensor as a whole is larger than the front and rear passages. In addition, the directions of the inflow passage 2 and the outflow passage 3 are limited to some extent, which poses problems such as the restriction of configuration C5 when incorporated into equipment as a sensor and the 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 provides a swirling means that swirls the fluid to be detected in an axial flow, and a swirling means in which a curved blade is provided around an axis along the substantially axial direction, and a swirling means that swirls the fluid to be detected in an axial flow. It consists of a rotating body that revolves perpendicularly to the flow direction, an outflow prevention means for keeping this rotating body within the range of the swirling flow, and a detection means for the rotating body, and the swirling means is configured to detect the curved blade. ”−
The flow side end portion is provided substantially parallel to the flow direction of the fluid to be detected, and is configured to have a curved shape with respect to the axial direction as it goes from the upstream side end portion to the downstream portion.

With this configuration, the fluid flow direction is the axial flow direction, and by rotating the rotating body whose area is smaller than the cross-sectional area of the flow path in the swirling flow caused by the swirling means, it becomes extremely small flow resistance, and is compact and compact. It is possible to obtain a flow rate detection device.

DESCRIPTION OF EMBODIMENTS 1 Next, embodiments of the present invention will be described based on FIGS. 3 to 5. In FIG. 3, reference numeral 10 denotes a housing 5' knee, and inside this housing 10 there are blades 11 that serve as swirling means for axially swirling the fluid to be detected.
It is fixed at 2. This wing 11 has a circular arc wing 13 and a shaft 14.
It consists of The upstream end 15 of the arcuate blade 13 is provided substantially parallel to the arrow 16 indicating the flow direction of the fluid to be detected. Further, the arcuate blade 13 is formed into an arcuate shape toward the downstream portion 17. A magnetic sphere 18 which is a rotating body is located downstream of the blade 11, and a sphere receiver 19 which is a means for preventing the magnetic sphere 18 from flowing out is fixed to the casing 12 downstream thereof. The configuration of the magnetic sphere 18 includes a hollow steel ball, a solid steel ball, a resin ball whose surface is plated with FeN1, and the like. A magnetic sphere 1 consisting of a permanent magnet 20 and a magnetic resistance element 21 is disposed outside the housing 10.
A rotation detector 22 serving as a detection means of 8 is provided to constitute a flow rate detection device. 23 is a retaining ring of the casing 12. 24 and 25 are an inlet and an outlet, and 26 is an arrow indicating the direction of rotation of the magnetic sphere 18. Figure 4 is a view of the blade 11 seen from the inlet 24 side.
1, and the gap 27 between the arc blades 13 is extremely small. FIG. 5 shows the spherical receiver 19, and 28 is the circumferential surface of the magnetic sphere 18, which has a conical shape. 29 is a flow path.

Next, the operation of the above configuration will be explained with reference to FIGS. 3 to 5. The fluid to be detected flowing in from the inlet 24 side flows into the blade 11
The air flows downstream along the arcuate blades 13 of the air, causing an axial swirl. As a result, the magnetic sphere 18 is rotated in a direction perpendicular to the direction of the flow due to the rotational flow. At this time, the magnetic sphere 18 contacts two points, the circumferential surface 28 of the sphere receiver 19 and the casing 12, and rotates. Since the number of rotations of the magnetic sphere 18 is proportional to the flow rate, the flow rate can be measured by measuring the number of rotations of the magnetic sphere per day.

This means that a permanent magnet 20 applies a magnetic field of constant strength to the magnetoresistive element 21, and when the magnetic sphere 18 passes through this magnetic field, the resistance change of the magnetoresistive element 21 is extracted and controlled as a voltage pulse change. Processed through a circuit (not shown), 7t, -2! It is. In this embodiment, the fluid to be detected is converted into a swirling flow by the arcuate blade 13, and the arcuate blade 13 has a simple blade shape among curved blades and is a preferable shape since it can reduce loss. The magnetic sphere 18 times is still a magnetic detection method and can be used even in opaque liquids.

Effects of the Invention As is clear from the second explanation, the flow rate detection device of the present invention has a swirling means for axially swirling the fluid to be detected, and a swirling means in which curved blades are provided around a shaft substantially along the axial direction; A rotating body located in this flow and rotating in a plane perpendicular to the direction of the flow, an outflow prevention means for keeping this rotating body within the range of the swirling flow, and a detection means for detecting the rotational speed of the rotating body. The swirling means is provided with an upstream end of the curved blade substantially parallel to the flow direction of the fluid to be detected, and a curved blade with respect to the axial direction as it goes from the upstream end to the downstream part. The configuration provides the following effects.

(1) Low flow resistance. Since the upstream end of the curved blade is provided substantially parallel to the flow direction of the fluid to be detected, loss when the fluid to be detected flows into the curved blade is small. Further, the loss caused when the fluid to be detected flows along the curved blade can also be reduced by using the curved blade. Furthermore, the rotating body has a much smaller diameter than the cross-sectional area of the flow path, and thus has low loss. Moreover, there is no bend in the flow path 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 advantage of creating an axial flow swirl in the straight pipe section and causing a rotating body to revolve around it.The flow path is the simplest and can be configured with a short flow path length. .

[Brief explanation of the drawing]

1 and 2 are horizontal and vertical cross-sectional views of the flow path of a conventional flow rate detection device, FIG. 3 is a sectional view of a flow rate detection device according to an embodiment of the present invention, and FIG. 4 is a fixed blade Fig. 5 is a perspective view of the appearance of the outflow prevention means. ...Axis, 15...
・"Second flow side end, 179 l knee zz...Downstream part, 18...Rotating body (magnetic sphere)
, 19... Outflow prevention means (spherical receiver), 22.
...Detection means (rotation detector) Name of agent Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (2)

[Claims] (1) The fluid to be detected flowing in the flow path is swirled in an axial flow, and a swirling means is provided with curved blades provided around the axis along the approximately axial direction, and a swirling means is positioned in the swirling flow and rotates in the direction of the flow. It consists of a rotating body that revolves in a vertical plane, an outflow prevention means that keeps this rotating body within the range of the swirling flow, and a detection means that detects the rotation speed of the rotating body, and the curved blade of the swirling means A flow rate detection device having a side end portion provided substantially parallel to a flow direction of the fluid to be detected, and having a curved shape with respect to an axial direction from the upstream end portion toward the downstream portion. (2) The flow rate detection device according to claim 1, wherein the curved blade is an arcuate blade.