JPH11108711A - Flow meter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic coupling type flow meter in which a follow body faithfully follow even if a flow rate changes suddenly, free from malfunctions and high in reliability. SOLUTION: In this flow meter, a magnet or a mover 4 with a built-in magnet in a tube body 1 is moved by fluidal force of a fluid flowing in the tube body and a magnet or a follow body 5 with a built-in magnet outside the tube body is moved by magnetic coupling with the mover and follows the mover. A magnet or a magnetic force generating body 8 for backup with a built-in magnet is provided outside the tube body 1 so as to confront the follow body such that two surfaces facing each other have the same polarity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a magnetically coupled flow meter.

[0002]

2. Description of the Related Art A flowmeter includes an area flowmeter which measures a flow rate by detecting displacement of a moving element in a pipe due to a fluid force of a fluid flowing in the pipe. There is a transparent tube such as a glass tube or a plastic tube so that the displacement state can be visually recognized from the outside. However, in the case of a glass tube or a plastic tube, there is a problem in terms of strength and corrosiveness due to a chemical solution. Therefore, a metal tube having high strength and corrosion resistance, for example, a stainless steel tube is used.

[0003] In a metal tube, the state of the moving member inside cannot be visually recognized from the outside. Therefore, a follower that follows the movement of the moving member is provided outside the tube. Has a built-in magnet or magnet, and the driven body is also formed of a magnet or a magnet built-in body, and is a so-called magnet coupling in which the moving element and the driven body are magnetically coupled.

In this magnet-coupled area flow meter, the follower follows the movement of the moving element as described above. However, if the flow rate of the fluid flowing through the tube changes abruptly, especially the first If the moving element moves rapidly by the fluid head at the time of inflow, the follower cannot follow it, and the magnetic coupling force between them will be smaller than the gravity of the follower, and the follower may return to the reference position. There is a problem that erroneous indication such as zero in the flow rate display often occurs.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic coupling type flow meter capable of solving the above-mentioned conventional problems by a follower faithfully following a sudden change in the flow rate.

[0006]

In order to achieve the above object, a flow meter according to the present invention is arranged such that a magnet or a moving element having a built-in magnet is moved by the fluid force of the fluid flowing through the inside of the tube, and the flowmeter is disposed outside the tube. In a flow meter in which a magnet or a driven body with a built-in magnet is moved following a moving element by magnetic coupling with a moving element, the magnet or back-up magnetic force generator with a built-in magnet or magnet has the same polarity as the surface facing the driven element. It is provided on the outside of the tube so as to face the driven body.

Further, more specific means of the present invention are as follows. <Specific Means 1> A magnet or a magnet with a built-in magnet having an apparent specific gravity larger than that of a fluid is provided in a tube having a fluid inlet at a lower portion and a fluid outlet at an upper portion, and the slider flows through the tube. In a flow meter that is moved by the fluid force of a fluid and a magnet or a driven body with a built-in magnet on the outside of the tube is moved following the moving element by magnetic coupling with the moving element, a magnetic force for backup with a built-in magnet or magnet The generator is provided outside the fluid inlet of the tube body so as to face the driven body so that the surface facing the driven body has the same polarity.

<Specific Means 2> A magnet having a magnet or a built-in magnet having an apparent specific gravity smaller than that of a fluid is provided in a tube having a fluid inlet at an upper portion and a fluid outlet at a lower portion. In a flow meter that is moved by the fluid force of the fluid flowing inside the body and a magnet or a driven body with a built-in magnet on the outside of the tube is moved following the moving element by magnetic coupling with the moving element, a backup with a built-in magnet or magnet The magnetic force generator for use is provided on the outer side of the fluid outlet of the tube body so as to face the driven body so that the surface facing the driven body has the same polarity.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on embodiments shown in the accompanying drawings. FIG. 1 shows a flowmeter according to a first embodiment of the present invention. Reference numeral 1 denotes a tube, which in this embodiment is a tapered tube whose inner surface at least increases in diameter toward the top, and is made of metal such as stainless steel. With a fluid inlet 2 at the bottom and a fluid outlet 3 at the top, fluid flows from below to above.

Reference numeral 4 denotes a mover provided in the tapered tube 1.
It is made of a magnet or a magnetic force generator containing a magnet, and the apparent specific gravity is larger than the specific gravity of the fluid flowing through the tapered pipe.

Reference numeral 5 denotes a follower that follows the movement of the mover, and is constituted by a magnet or a magnetic force generator containing a magnet.
It is arranged around the tapered tube with a ring shape,
Also, the movable member is magnetically coupled so as to be stationary, and a plurality of vertical holes 6 drilled in place are fitted in a plurality of vertical guide shafts 7 so that the vertical holes 6 can move up and down along the guide shafts 7. It has become.

Further, in the present invention, a ring-shaped backup magnetic force generator 8 having the same pole on the surface facing the follower is provided below the follower, that is, on the inlet side of the tapered tube. The backup magnetic force generator is constituted by a magnet or a magnet having a built-in magnet.

In the drawing, reference numeral 9 denotes a guide shaft of the mover, which stands on the center axis line in the tapered tube.
A vertical hole 15 formed in the center of the mover is loosely fitted thereto. Reference numeral 10 denotes an index piece provided on the driven body, 11 denotes a flow rate display scale plate, 12a denotes an upper stopper for the mover, 1
2b denotes the lower stopper.

[0014]

In this embodiment, the moving element 4 moves up and down in the tapered tube due to a change in the flow rate of the fluid flowing in the tapered tube 1, and the follower also moves up and down following the movement. When the mover 4 is stationary in the tapered tube 1 at a position corresponding to the flow rate of the fluid, the follower 5 is opposed to the mover 4 against the repulsive force (f) with the backup magnetic force generator 8. It is stationary by the magnetic coupling force (F), and the magnetic coupling force (F) is larger than the repulsion force (f).

In this state, when the flow rate rapidly increases and the moving element rapidly rises, when the moving element starts to rise, the distance between the moving element and the driven body increases, and the magnetic coupling force between them, that is, Since the magnetic coupling force (F) between the mover and the driven body, which has suppressed the repulsion force with the backup magnetic force generator 8, becomes small, the driven body uses the repulsion force (f) of the backup magnetic force generator 8. ) And rises following the moving element.

Therefore, even if the flow rate suddenly increases,
The follower cannot follow and cannot be left behind. When the flow rate suddenly decreases, the moving element descends by its own weight, and the driven body also descends by its own weight and the magnetic coupling force with the moving element.

FIG. 2 shows a second embodiment of the present invention. In this embodiment, the tube 1 is a straight tube, but has an orifice 13 inside, and the moving member 4 is formed of a tapered body having a large thickness. The moving element is an area flow meter that moves up and down in the orifice 13 according to a change in the flow rate, and the operation is the same as that of the first embodiment.

FIG. 3 shows a third embodiment of the present invention, in which the tube is a straight tube, and the moving member is connected to the upper stopper 12a.
It is assumed that a resistance force is applied to the flow of the fluid by the compression spring 14 therebetween. In this flow meter, the flow rate is measured by moving the moving element 4 against the spring 14 by the fluid force of the fluid, and the relationship between the magnetic force generator for backup and the driven body is the first and second embodiments. The operation is the same as that of the first and second embodiments.

Since the spring 14 provides a resistance to the flow of the fluid to the moving element, the moving element may be pulled downward by a tension coil spring.

FIG. 4 shows a fourth embodiment of the present invention. In this embodiment, the tubular body 1 is a tapered tubular body whose inner surface at least expands in diameter toward the lower side, and is made of metal such as stainless steel and has a fluid inlet 2 at an upper part and a fluid outlet 3 at a lower part. Fluid is allowed to flow. Reference numeral 4 denotes a moving member provided in the tapered tube 1, which is constituted by a magnet or
Alternatively, it is constituted by a magnetic force generator incorporating a magnet, and the apparent specific gravity is smaller than the specific gravity of the fluid flowing through the tapered pipe.

Reference numeral 5 denotes a follower that follows the movement of the mover, and is constituted by a magnet or a magnetic force generator containing a magnet.
It is arranged around the tapered tube with a ring shape,
Also, the movable member is magnetically coupled so as to be stationary, and a plurality of vertical holes 6 drilled in place are fitted in a plurality of vertical guide shafts 7 so that the vertical holes 6 can move up and down along the guide shafts 7. It has become.

Further, in this embodiment, the ring-shaped backup magnetic force generator 8 having the same pole on the surface facing the follower is provided below the follower, that is, on the outlet side of the tapered tube. The backup magnetic force generator is constituted by a magnet or a magnet having a built-in magnet.

In the drawing, reference numeral 9 denotes a guide shaft of the mover, which stands on the center axis in the tapered tube.
A vertical hole formed in the center of the moving element is fitted into the moving element. Reference numeral 10 denotes an indicator piece provided on the driven body, 11 denotes a flow rate display scale plate, 12a denotes an upper stopper for the moving element, and 12b denotes a lower stopper for the moving element. Is shown.

The moving element has an apparent specific gravity smaller than that of the fluid. For this purpose, for example, a compression coil spring is interposed between the lower part of the moving element and the lower stopper 12b of the tube, or the upper end is moved. The lower force of the lower tension coil spring fixed to the upper stopper 12a is fixed to the mover by applying a lifting force to the mover, or a hollow body in which the upper and lower ends of the cylindrical magnet are closed by a sealing body. I do.

[0025]

In this embodiment, the moving element 4 moves up and down in the tapered tube due to a change in the flow rate of the fluid flowing in the tapered tube 1, and the follower also moves up and down following the movement. When the mover 4 is stationary in the tapered tube 1 at a position corresponding to the flow rate of the fluid, the follower 5 is opposed to the mover 4 against the repulsive force (f) with the backup magnetic force generator 8. It is stationary due to the magnetic coupling force (F). Even if the flow rate suddenly increases from this state and the moving element descends rapidly, the follower descends due to its own weight and magnetic coupling with the moving element and follows the moving element.

Conversely, even if the flow rate suddenly decreases and the movable element rises rapidly, the distance between the movable element and the follower increases when the movable element starts to rise, and the magnetic force between the movable element and the driven element increases. Since the coupling force, that is, the magnetic coupling force (F) between the mover and the follower, which has suppressed the repulsion between the backup magnetic force generator 8 and the follower, becomes smaller, the follower becomes the backup magnetic force generator 8. It is pushed up by the repulsion force (f) and rises following the moving element. Therefore, even if the flow rate suddenly decreases, the driven body cannot follow and cannot be left behind.

FIG. 5 shows a fifth embodiment of the present invention. In this embodiment, the tube 1 is a straight tube, but has an orifice 13 inside, and the moving element 4 is formed of a tapered body having a lower thickness. The moving element is an area flow meter that moves up and down in the orifice 13 according to a change in the flow rate, and the operation is the same as that of the fourth embodiment.

FIG. 6 shows a sixth embodiment of the present invention, in which the tube is a straight tube, and the moving member is connected to the lower stopper 13b.
It is assumed that a resistance force is applied to the flow of the fluid by the compression spring 14 therebetween. In this flow meter, the flow rate is measured by moving the mover 4 against the spring 14 by the fluid force of the fluid, and the relationship between the magnetic force generator for backup and the follower is the fourth or fifth embodiment. The operation is the same as that of the fourth and fifth embodiments. .

Since the spring 14 gives the moving element a resistance to the flow of the fluid, the moving element may be pulled upward by a tension coil spring.

[0030]

According to the present invention, even if the flow rate of the fluid changes abruptly and the moving element is rapidly moved, the driven body faithfully follows the moving element and the driven body malfunctions. And a highly reliable magnetically coupled flowmeter can be provided.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of a flow meter according to the present invention.

FIG. 2 is a longitudinal sectional view showing a second embodiment of the flow meter according to the present invention.

FIG. 3 is a longitudinal sectional view showing a third embodiment of the flow meter according to the present invention.

FIG. 4 is a longitudinal sectional view showing a fourth embodiment of the flow meter according to the present invention.

FIG. 5 is a longitudinal sectional view showing a fifth embodiment of the flow meter according to the present invention.

FIG. 6 is a longitudinal sectional view showing a sixth embodiment of the flow meter according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 pipe 2 fluid inlet 3 fluid outlet 4 mover 5 follower 6 vertical hole of follower 7 guide shaft of follower 8 magnetic force generator for backup 9 guide shaft of mover 10 indicator piece 11 scale plate 12a 12b stopper 13 Orifice 14 Spring 15 Vertical hole of slider

Claims (1)

[Claims] A magnet or a movable member with a built-in magnet in a tube is moved by the fluid force of a fluid flowing through the tube, and a magnet or a driven member with a built-in magnet on the outside of the tube is magnetically coupled to the movable member. In a flow meter that is moved to follow, a magnet or a backup magnetic force generator with a built-in magnet is provided on the outside of the tube by facing the driven body so that the surface facing the driven body has the same polarity. Flow meter.