JPH01265121A - Flow rate detector - Google Patents

Abstract

PURPOSE:To prevent rotational deterioration and a rotation stop due to foreign matter in a fluid by generating a revolving flow of the fluid by a revolving means and rotating a ferroelectric spherical body smoothly, and detecting the rotating speed, i.e. flow rate. CONSTITUTION:The fluid flows into a housing 4 as shown by an arrow and is revolved by the revolving means 6 in its flow passage 5 and the spherical body 7 has momentum by the revolving flow of the fluid and revolves in a cylindrical body 9 at right angles to the flow passage direction at the position where the spherical body contacts the internal wall of the cylindrical body 9 and an outflow preventing means 8. The rotating speed based upon the revolution is correlative to the flow rate of the fluid and in proportional relation, and a magnetic detecting means 11 detects the rotating speed of the magnetic spherical body 7. The magnetic detecting means 11 outputs pulses, which are processed by a control circuit and detected as an instantaneous flow rate or integral flow rate.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a flow rate detector that detects the flow rate of water or hot water in a water heater or hot water heater, or the fuel flow rate in a liquid fuel supply device.

Conventional technology There are various methods for measuring flow rate, and a simple method that can be applied to general consumer equipment is one that converts the rotational speed of a movable body such as an impeller that rotates in proportion to the flow rate into an electrical signal, which measures a total of 111
There is something to do. An example thereof will be explained in FIG.

The figure shows a vane-wheel type flow sensor, in which an impeller 1 is provided with an axis supported in the flow path, and a magnetic detection sensor 3 is attached outside the pipe line 1a by a permanent magnet 2 embedded in the outer periphery of the impeller.
By operating the pump and detecting its rotation, a bus output with a frequency proportional to the flow rate is obtained. .

Problems to be Solved by the Invention However, with the above configuration, there is a risk that the bearing 1C is located in the flow path 1b in the conduit 1a, and the rotation speed accuracy may be lowered or the bearing may deteriorate due to the intrusion of foreign matter, and the flow path Permanent magnet 2 inside
If foreign matter adheres to the inner surface of the passageway and reaches the inner surface of the passage, there is a problem in that there is a risk of deterioration of rotation accuracy or rotation stoppage.

The present invention is intended to solve such conventional problems, and aims to provide a flow rate detector that is resistant to foreign matter and can provide a high detection signal level without installing a bearing in the flow path.

Means for Solving the Problems In order to solve the above problems, the present invention provides a swirling means for swirling fluid in a flow path, a ferromagnetic sphere that rotates in the swirling flow downstream of the swirling means, and a ferromagnetic sphere that rotates in the swirling flow downstream of the swirling means. an outflow prevention means for keeping the sphere within the range of the swirling flow; a magnetic detection means located on the outer periphery of the flow path; This is a flow rate detector with a spherical magnet inserted.

Effect: With the above configuration, the swirling means generates a swirling flow in the fluid,
By rotating the ferromagnetic sphere smoothly, it is possible to detect the rotational speed, that is, the flow rate.

Example Embodiments of the present invention will be described below based on the drawings.

In FIG. 1, 4 is a housing forming a flow path 5;
Inside the housing 4, a rotating means 6, a ferromagnetic sphere 7, and a means 8 for preventing the sphere from flowing out are provided at appropriate intervals in order from the upstream side. The swirling means 6 is a non-rotating fixed impeller having a plurality of blades twisted in the same direction between the outer periphery and the center, and gives a swirling flow to the fluid. The outflow prevention means 8 has a center hole and an arcuate hole around the periphery, and the upstream end thereof is annular in the direction of flow and the end portion is a flat surface, which serves as a receptacle for the sphere 7 to revolve around.

The ferromagnetic sphere 7 rotates while contacting the inner peripheral surface of a cylinder 9 that is integrally formed with the rotating means 6 and the outflow prevention means 8, and the upstream flat surface 10 of the outflow prevention means 8. conduct. 1
Reference numeral 1 denotes a magnetic detection means, which detects the rotational speed of the sphere 7 as a pulse output using a magnetic resistance element or a Hall element and an amplifier circuit. It is fixed to the outside of the housing 4 on the outer periphery of the orbit.

Next, details of the ferromagnetic sphere 7 are shown in FIGS. 2 to 4. FIG. 2 is a cross-sectional view of the ferromagnetic sphere 7, which has a two-layer spherical structure with a hollow part 1a inside, a spherical permanent magnet 14 inserted inside, and a resin mode 14a outside. Permanent magnet 14
As shown in Figure 3, it has a hollow spherical shape, and the outer surface is all N poles, and the inside of the hollow side is all S poles, or the outer surface is S pole and the inside is N pole. are formed with the same polarity, and the magnetic flux is configured to uniformly extend radially from the center of the sphere. Although it is difficult to configure the permanent magnet 14 as described above, an example of how to configure it is shown in the fourth section.
As shown in the figure. It is possible to divide a hollow spherical permanent magnet into two and magnetize each as shown in the figure.It is possible to combine two hollow hemispheres 14' whose outer and inner surfaces are magnetized with different polarities, and to create an outer magnet. The ferromagnetic sphere 7 shown in FIG. 2 is formed by resin molding 14a.

In the above configuration, the fluid flows into the housing 4 from the direction indicated by the fluid force flow in FIG.
The sphere 7 obtains a kinetic force due to the swirling flow of the fluid.
It goes around inside the cylinder 9 in a direction perpendicular to the flow path direction at a position where it contacts the inner wall of the cylinder 9 and the outflow prevention means 8 . The rotational speed of the ferromagnetic sphere 7 is correlated with the flow rate of the fluid, and in this configuration, the rotational speed of the ferromagnetic sphere 7 is detected by the magnetic detection means 11. The magnetic detection means 11 outputs a pulse, which is calculated by a control circuit (not shown) and detected as an instantaneous flow rate or an integrated flow rate. The rotational speed level of the sphere 7 can be appropriately set according to the application by selecting the twist angle of, for example, a blade wheel of the turning means 6. In the above configuration, the material of the sphere 7 is not particularly specified, such as changing depending on the type of fluid, but the minimum detectable flow rate of the fluid can be lowered by using a lightweight non-metallic material such as resin. It is advantageous. In the embodiment, a fixed impeller is used as a means to cause swirling flow in the fluid, but
There are various means such as a flat plate twisting member and a cylindrical member having several diagonal holes, and the outflow prevention means may also be a flat plate with a large number of holes through which the sphere cannot pass. In the configuration of the embodiment, the impeller as a fluid swirling means has less resistance and is effective in generating a stronger swirling flow, and the annular shape with a flat part as a means for preventing outflow is similar to a sphere. Each of these configurations is advantageous, such as being effective for stable orbiting, but there are many methods available depending on the type of fluid and the required performance level, and the above methods are not limited to the configurations of the embodiments. do not have. Furthermore, the flow path is not limited to a circular cross section.

As described above, the present flow rate detector has a simple structure and high accuracy, is resistant to foreign substances in the fluid, has low water flow resistance, and can measure flow rates over a wide range.

Next, another embodiment of the present invention will be explained using FIGS. 5 and 6. In FIG. 5, 4 to 12 are the same as in FIG. A permanent magnet is provided at a position where it is in contact with the magnet, and it applies a bias magnetic field to the magnetic detection means 11.It is effective in increasing the detection pulse level of the magnetic detection means 11 due to the rotation of the ferromagnetic sphere 7 into which the permanent magnet is inserted. Furthermore, even if the magnetic level of the permanent magnet of the sphere 7 is weakened, the detection level can be increased due to the influence of the bias magnetic field.If the magnetic detection means 11 has a high detection level, It can also be made strong against various types of noise when applied.In other words, various methods can be considered for the magnetic detection means 11.Next, FIG. An example of application is shown. 16 is an annular passage with a circular cross section, and an inlet passage 17 and a jet nozzle 1v18 are opened on the outer periphery of this passage.
It has an outlet passage 19 in the center. 20 is a ferromagnetic sphere within the annular passage, and 2) is a magnetic detection means for detecting the rotational speed of the sphere 2), which is provided outside the annular passage. Fluid ejects from the nozzle/'
The ferromagnetic sphere 20 is ejected from the arrow in the direction of the arrow, and the ferromagnetic sphere 20 goes around the annular passage 16, and the rotational speed according to the flow rate is detected by the magnetic detection element 2.
) to determine the flow rate. This type of flow rate detector is used to measure weak flow rates, and the configuration of the present invention allows simple and reliable measurement.

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

(1) The fluid is swirled by a swirling means such as a fixed impeller, and the swirling flow rotates the sphere, and there are no narrow parts in the passage, such as between the bearing or the tip of the rotating blade and the inner diameter of the passage, so it is possible to There is no risk of rotation deterioration or rotation stoppage due to foreign objects, and since the outside of the ferromagnetic sphere is molded with resin and the permanent magnet is not in direct contact with the fluid, it is resistant to fluids containing iron powder, etc. is also a stronger configuration and provides a more reliable flow detector.

? ）Although the polarity of the permanent magnet inserted inside the ferromagnetic sphere is spherical, it has the same polarity with respect to the outside and the magnetic force is uniform, making stable detection possible with magnetic detection means. , the magnetic detection means is also simplified, such as by simplifying the circuitry.

(3) The outside of the rotating body is made of resin and is lightweight, so it is easy to operate even with small flow rates and has a wide detection flow range as a flow rate detector.Furthermore, the kinetic energy due to rotation is small, so there is no wear or noise caused by contact rotation. Extremely small.

(4) The spherical permanent magnet inserted into the ferromagnetic sphere is composed of two hollow spheres, so that the surface and inside of the sphere are composed of separate and identical poles, and it is possible to make the magnetic force uniform, allowing magnetic detection. stable detection is possible.

(51) The rotating means, the sphere, and the outflow prevention means all have extremely low resistance with respect to the passage diameter, and furthermore, as a flow rate detector, the flow passage and structure are simple, small and compact, and it is suitable for application to equipment.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the flow path of a flow rate detector according to the first embodiment of the present invention, FIGS. 2 to 4 are enlarged sectional views of the ferromagnetic sphere and its essential parts, and FIGS. 5 and 6 are FIG. 7 is a cross-sectional view of the flow path of a flow rate detector in the embodiment of the same polarity, and FIG. 7 is a cross-sectional view of the flow path of a conventional flow rate detector. 5...Flow path, 6...Swivel means, 7...
...Ferromagnetic sphere, 8...Outflow prevention means, 1
1... Magnetic detection means, 14... Spherical magnet. Name of agent: Patent attorney Toshio Nakao and 1 other person5-
・Flow path diagram 2 3v! J Figure 5 Figure 6 I? 018

Claims (2)

[Claims] (1) A swirling means for swirling the fluid in the flow path, a ferromagnetic sphere positioned in the swirling flow and rotating, and an outflow prevention means for keeping the sphere within the range of the swirling flow. , a flow rate detector comprising a magnetic detection means located on the outer periphery of a flow path, the sphere having an outer surface made of resin, and a spherical magnet whose outer surface is all of the same polarity inserted inside. (2) The flow rate detector according to claim 1, wherein the spherical magnet is divided into two hollow parts.