JPS61122521A - Flow rate detector - Google Patents

Abstract

PURPOSE:To secure high operation reliability against foreign matter in fluid such as dust, sand, and iron rust and scale production by allowing a spherical body to receive a swivel flow generated by a swiveling means and rotates in contact an annular internal wall surface perpendicular to the flow direction. CONSTITUTION:The fluid is placed in swiveling motion in addition to axial motion when passing through the swiveling means 12 and the spherical body 17 receives the force of the swivel and rotates in contact with the annular internal wall surface 16. The rotation of the spherical body 17 is limited within the influence range of the swivel flow by a flowing-out preventing member 14. For the purpose, the interruption of light switch is caused every time the spherical body 17 crosses the optical axis between the light emitting element 18 and photodetecting element 19 provided while aligned to the track surface of the rotation is detected as an electric pulse signal to obtain the number of rotations of the spherical body 17, i.e. flow rate. The spherical body 17 rotates while pressed against the annular internal surface 16 with centrifugal force, so sticking scale deposition components are wiped away and transmissivity is not spoiled.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to the construction of a detector for measuring fluid flow rate.

Conventional technology Although various operating principles are known for measuring fluid flow rate, it is easy to obtain an electrical signal output. The rotation is transmitted to a permanent magnet 4 outside the flow path, which is provided opposite the permanent magnet 3 integrated with the impeller 1, and the rotation of the permanent magnet 4 is detected by a magnetic sensor 5.
It is now detected by . On the other hand, the conventional impeller JE6, which does not use bearings, gives the fluid a flow in the swirling direction.
The rotational speed of the sphere 7, which rotates due to the flow, is detected by the light emitting element 8 and the light receiving element 9.

Problems to be Solved by the Invention The conventional example shown in FIG. This may cause unevenness. In particular, when used to measure the flow rate of water, there is a possibility that iron rust in the piping will attract and adhere to the permanent magnet, making it impossible to rotate. On the other hand, in the conventional example shown in Fig. 8, there is no risk of bearing malfunction or iron rust, but when used to measure water flow rate, scale adheres to the inner surface of the flow channel, causing light to pass through the light-emitting and light-receiving elements. There was a possibility that the sensitivity would be lost, resulting in poor detection. The present invention solves the problems of the prior art, and aims to ensure high operational reliability against foreign matter such as dust, sand, iron rust, and scale formation in the fluid.

Means for Solving the Problems In order to solve the above problems, the flow rate detector of the present invention includes:
a traveling means provided in the flow path, a sphere that receives the swirling flow and rotates while contacting an annular inner wall surface in a direction perpendicular to the flow direction, and an outflow prevention member that keeps the sphere within the influence range of the swirling flow; It has a configuration consisting of light emitting and light receiving elements provided in the radial direction of the orbital surface of a sphere.

, Operation The present invention has the above-described configuration, which not only allows the number of rotations of the sphere to be proportional to the flow rate, but also prevents malfunctions due to foreign matter clogging and adhesion of iron powder, even though the configuration does not include bearings or permanent magnets. There is no fear. In addition, since the sphere revolves around the annular inner wall surface of the flow path while always being in contact with it, the contact surface is constantly wiped and no scale components are deposited or deposited. Therefore, there is no reduction in the detection sensitivity of the light emitting and light receiving elements, and high reliability can be ensured. In particular, since the spherical body, which is a rotating body, revolves around its axis while making irregular rotational movements due to the swirling flow, a high effect of preventing scale adhesion to the contact inner wall surface is obtained.

Embodiments Hereinafter, embodiments of the present invention will be explained based on the accompanying drawings. 1 and 2, on the upstream side of a flow path 11 passing through the housing 10, there is a fixed impeller-shaped travel imparting means 12 that applies swirling force to the fluid, and downstream thereof there is a through hole 13. The outflow prevention member 14 is provided with a plurality of . A sphere 17 is inserted between the travel force applying means 12 and the outflow prevention member 14, and the sphere 17 circulates in a direction perpendicular to the flow direction while contacting the central inclined surface 15 of the outflow prevention means 14 and the annular inner wall surface 16 of the flow path. There is. There are a light emitting element 18 and a light receiving element 19 placed at symmetrical positions in the radial direction of the orbital surface on which the sphere orbits, and each element is connected to the annular inner wall surface 16.
Only the tip 2o facing the front end 2o is translucent, and the other surfaces are housed in a resin case 21 plated with metal to reflect light. Of course, the tip 20 of the resin case 21 is connected to the channel inner wall surface 1.
It is finished so that it is flush with 6.

In the above configuration, when the fluid Id passes through the swirling means 12, it becomes a flow with traveling motion added to the axial motion, and the sphere 17/
In response to the turning force, the ring moves around while contacting the annular inner wall surface 16. Since the turning momentum is proportional to the flow rate, the force that causes the sphere 17 to revolve is also proportional to the flow rate, and the rotational speed shows a value representative of the flow rate. Since this orbit plane and the optical axes of the light emitting element 18 and the light receiving element 19 coincide, each time the sphere 17 crosses the optical axis, the light is blocked and can be detected as an electrical pulse signal. Since the sphere 17 rotates while being pressed into contact with the annular inner wall surface 16 due to centrifugal force, adhesion of scale deposits is constantly wiped off, so that the translucency is not impaired. In the conventional example shown in Fig. 5, the sphere 7 rotates in an annular V-shaped groove separated from the inner wall surface, so it is not effective in preventing scale from adhering to the inner surface on the optical axis. .

Next, another embodiment of the present invention will be described with reference to FIGS. 3 and 4. Here, the annular inner wall surface on which the sphere 17 contacts and revolves is formed of an annular transparent resin 22, and the light emitting and light receiving element 1
8.19, each tip is in contact with the outside of the annular transparent resin 22, and the other parts have the same structure as the embodiment shown in FIGS. 1 and 2, and perform the same function. In this embodiment, since the mating members that the sphere 17 comes into contact with are made of the same material, there is no change in the coefficient of friction during rotation, resulting in uniform rotation. Moreover, in the embodiment shown in FIG. 2, the housing 10 and the resin case 2 are
Nonuniform wear, which is a concern when 1 is made of a different material, does not occur. Of course, the scale prevention effect is the same.

Furthermore, other embodiments of the present invention are shown in FIGS. 5 and 6.

Here, optical fibers 23 and 24 connected to a light-emitting element 18 and a light-receiving element 19 are exposed on the orbital plane of the annular inner wall surface 16 around which the sphere 17 revolves, and only the tips of the two optical fibers are transparent. The end face is held in a resin case 25 having optical properties.

The light emitting element 18 and the light receiving element 19 are mounted on a separate printed circuit board 26.
, and forms a signal processing circuit 27. The other parts have the same structure and function as the embodiment shown in FIG. In this embodiment, the light is reflected when the sphere 17 is at the position shown in the figure, and the light is diffused when the sphere 17 is at any other position. Less processing is required and the signal processing circuit 2
Since the light-emitting element 18 and the light-receiving element 19, which are electrical parts, are provided in the light emitting element 7, there is no electrical connector and there is no risk of accidents caused by poor contact.

Effects of the Invention As described above, the flow rate detector of the present invention provides the following effects.

(1) Since it detects the circular motion of a sphere, it does not require bearings or permanent magnets in the flow path, does not cause performance deterioration due to foreign matter in the fluid, and is highly reliable for long-term use.

■ The optical axes of the light emitting element and light receiving element are placed on the orbiting surface of the sphere, so the inner wall surface of the orbit is always wiped clean, so there is no deterioration in translucency due to scale adhesion, making it reliable for long periods of time even for water level detection. Rich in sex.

■ Since no magnetic sensor is used, there is no risk of generating false signals even if a solenoid or motor is installed in close proximity. Also, the change in the amount of light received as the sphere approaches and moves away is
Since the variation range is significantly wider than the variation in the amount of magnetic flux due to the proximity and separation of the permanent magnets, the signal is digitized, the signal-to-noise ratio is high, and the processing circuit is easy.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a flow rate detector according to a first embodiment of the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, and FIG. 3 is a sectional view showing a second embodiment of the present invention. Figure 4 is A- of Figure 3.
5 is a sectional view showing the third embodiment of the present invention, FIG. 6 is a sectional view taken along line A-A in FIG. 5, and FIGS. 7 and 8 are a conventional flow rate detector. FIG. 11...flow path, 12...axial flow swirling means, 14...
...Outflow prevention member, 16...-annular inner wall surface,
17... Sphere, 18-... Light emitting element, 19...
. . . Light receiving element, 22 . . . Annular translucent resin. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 3
Figure 4

Claims (2)

[Claims] (1) A means for axially swirling the fluid in the flow path; a sphere located in the swirl flow and circulating in contact with an annular inner wall surface of the flow path in a direction perpendicular to the flow direction; A flow rate detector comprising an outflow prevention member that keeps the swirling flow within the range, and a light emitting and light receiving element that is provided in the radial direction of the orbital surface of the sphere and detects the rotation speed of the sphere. (2) The flow rate detector according to claim 1, wherein the annular inner wall surface around which the sphere contacts is made of an annular transparent resin.