JPS6228407B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to improvements in flow meters.

[Prior Art] Conventionally, when measuring the flow rate electrically in area type flowmeters, an optical method has been used to detect the position of the float, but with this method, There were problems such as measurement errors if dust particles were floating or the glass taper tube was dirty. Additionally, this optical method cannot be used for opaque liquids or synthetic resin pipes, and the device itself has many components and is expensive, making it unsuitable for practical use in area flowmeters. .

In addition, as an electromagnetic detection method, for example, an actuating transformer is used, but these have the problem that a large coil must be used to widen the movement range of the float, making the device large and expensive. It was hot.

[Problem that the invention seeks to solve]

The present invention has been made based on the above-mentioned viewpoints, and its purpose is to simplify the configuration of the measuring device itself and make it inexpensive, and to prevent dirt on the tube body, dust in the air, etc. It is an object of the present invention to provide a flow meter that is not affected by the flow, has a wide movable range of the float, can always obtain constant measurement results with high precision, and can output measurement signals as displays, control signals, etc.

[Means for solving problems]

The above purpose is to use a flowmeter that allows fluid to flow through a tapered pipe into which a float is inserted, moves the float in accordance with the flow rate, and determines the flow rate based on the position of the float. A coil is provided at the end of the tapered tube, the axial length of which is extremely short compared to the tapered tube, and the cross-sectional area perpendicular to the axis is sequentially arranged in the axial direction of the tapered tube over the entire floating range of the float from the coil. This is achieved by a flowmeter that is provided with a variable magnetic member and further provided with a circuit that converts the reactance change of the coil into an electrical signal to measure the flow rate.

[Effect]

Therefore, when using the flowmeter according to the present invention, the configuration of the measuring device itself can be simplified, the cost can be kept low, and the movement of the float is not affected by dirt on the tube or dust in the air. The possible range is wide, and therefore highly accurate and constant measurement results can be obtained, and furthermore, the measurement signal can be output as a display, control signal, etc.

〔Example〕

Hereinafter, the configuration of the present invention will be specifically explained with reference to the drawings.

FIG. 1 is an explanatory diagram showing one embodiment of a flowmeter according to the present invention, FIG. 2 is an explanatory diagram showing another embodiment, and FIG. 3 is an explanatory diagram showing still another embodiment. FIG. 4 is a sectional view taken along line AA in FIG. 3.

First, FIG. 1 will be explained.

In FIG. 1, 1 is a tapered tube, 2 is a reactance coil, 3 is a float, 4 is a high frequency power source, and 13 is an instrument that displays the reactance of the coil 2 in terms of voltage, the position (cm) of the float 3, etc.

One reactance coil 2 is provided at one end of the outer periphery of the tapered tube 1, and a float 3 is housed inside the tapered tube 1.
Float 3 above contains 65% ferrite grains in synthetic resin.
The frequency of the high frequency power source 4 connected to the reactance coil 2 is 5M.
Hz, position detection of the float 3 is effective up to 15 cm.

Next, FIG. 2 will be explained.

In FIG. 2, 5 is a tapered tube, 6 and 7 are reactance coils, 8 is a float, and 9 is a high frequency power source.

As shown in FIG. 2, reactance coils 6 and 7 are provided at both ends of the outer circumference of the tapered tube 5.
When using the float 8 having the same structure as above and setting the frequency of the high frequency power source 9 to 5 MHz, the position detection of the float 8 is effective up to 30 cm.

Therefore, as mentioned above, in a flowmeter for a small flow rate, it is sufficient to measure the flow rate by providing only one or two reactance coils.

Furthermore, as shown in FIGS. 3 and 4, the inner surface of the tapered tube 10 is provided with an elongated strip, strip, etc. whose width gradually becomes narrower (or wider) as it goes downward along its longitudinal direction. The upper limit of the effective detection position of the float 12 can be increased by attaching two sheets of high magnetic permeability material 11 so as to face each other.

Note that the shape of the high magnetic permeability material 11 is not limited to the above, and the width may be constant. Furthermore, a paint containing a magnetic material other than the high magnetic permeability material 11 may be applied to the tapered tube.

〔Effect of the invention〕

Since the present invention is configured as described above, when using the flowmeter according to the present invention, the configuration of the measuring device itself can be simplified and made inexpensive, and it is not affected by dirt on the pipe body or dust in the air. , it is possible to provide a flowmeter in which the float has a wide range of movement, and therefore highly accurate and constant measurement results can be obtained at all times. Furthermore, since the flow rate can be detected as an electrical signal, it is possible to automatically control the flow rate or record the flow rate from time to time.

Note that the configuration of the present invention is not limited to the above-mentioned embodiments. That is, for example, if the tapered tube used is uniform and has high precision, the wound reactance coil does not need to be a mounted winding. A large number of coils may be printed in advance and attached to the tapered tube by pasting or the like. In addition, the configuration of the flow rate measuring circuit and its elements can be freely modified within the scope of the purpose of the present invention, and the present invention encompasses all of them.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing one embodiment of a flowmeter according to the present invention, FIG. 2 is an explanatory diagram showing another embodiment, and FIG. 3 is an explanatory diagram showing still another embodiment. FIG. 4 is a sectional view taken along line AA in FIG. 3. 1, 5, 10... Tapered tube, 2, 6, 7... Reactance coil, 4, 9... High frequency power supply, 3, 8, 1
2...Float, 11...High magnetic permeability material.

Claims (1)

[Claims] 1. A flow meter in which fluid flows through a tapered pipe into which a float is inserted, the float is moved in accordance with the flow rate, and the flow rate is determined by the position of the float, wherein the float is made of a magnetic material. , a coil is provided at the end of the tapered tube, the axial length of which is extremely short compared to the tapered tube, and the cross-sectional area perpendicular to the axis of the coil changes sequentially in the axial direction of the tapered tube over the entire floating range of the float. The above-described flowmeter includes a magnetic member and further includes a circuit that converts the reactance change of the coil into an electric signal to measure the flow rate. 2. The flowmeter according to claim 1, wherein the coil is provided only at one end of the tapered tube. 3. The flowmeter according to claim 1, wherein one coil is provided at each end of the tapered tube. 4. The flowmeter according to claim 1, wherein the tapered tube also serves as the magnetic body portion. 5. The flowmeter according to claim 1, wherein the tapered tube is provided separately from the magnetic body section.