JP2000337539A - Check valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the reliability of a check valve and secure the versatility of the valve. SOLUTION: The check valve is equipped with a hollow conduit 1 furnished at one end with a flow inlet 3 and at the other end with an outlet 5, a poppet 7 installed movably in the conduit 1, an outer magnet 19 installed on the conduit 1, and an inner magnet 15 installed inside the poppet 7, wherein the poppet movement and its direction are decided by the relation of the differential pressure between the pressure B at the outlet and the pressure A at the inlet to the magnetic forces M of the inner 15 and outer magnet 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a check valve which prevents a liquid from flowing backward and flows only in one direction, and more particularly to a check valve utilizing magnetic force. The check valve according to the present invention is, for example,
Used for pure water, chemicals, etc.

[0002]

2. Description of the Related Art In a conventional check valve, a poppet generally provided in a conduit is held by a coil spring, and the poppet is moved by using a biasing force of the coil spring.

[0003]

Since the check valve opens and closes the flow path by the pressure of the fluid, a pressure loss inevitably occurs. Generally, the smaller the pressure loss, the better, and the smaller the operating pressure for opening and closing the flow path, the better. According to conventional check valves, this pressure loss depends on the capacity of the coil spring. For example, when the coil spring is made of plastic due to the nature of the fluid, the coil spring made of plastic has a disadvantage in that the elastic force thereof is greatly deteriorated with time and reliability is reduced. Further, the coil spring made of plastic is difficult to manufacture, and it is necessary to respond individually to provide various elasticity, so that there is a disadvantage that the cost is increased accordingly.

[0004] It is an object of the present invention to solve the above-mentioned drawbacks and to improve the reliability of the valve and ensure the versatility of the valve.

[0005]

In order to achieve the above object, a check valve according to the present invention comprises a hollow conduit having an inlet at one end and an outlet at the other end, and movable in the conduit. , An external magnet provided in the conduit, and an internal magnet provided in the valve element, wherein the valve element has a differential pressure between the pressure on the outlet side and the pressure on the inlet side and the inner and outer magnets. The presence / absence and direction of the movement are determined based on the relationship with the magnetic force. Further, in the check valve according to the first aspect, the polarity of the external magnet and the polarity of the internal magnet are different. Further, in the check valve according to the first aspect, the polarities of the external magnet and the internal magnet are the same. In the check valve according to the first aspect, the external magnet is provided on an outer periphery of the conduit. In the check valve according to the first aspect, the external magnet is provided on an inner periphery of the conduit.
The check valve according to claim 1, wherein the external magnet is embedded in the conduit. In the check valve according to the first aspect, the conduit may be divided into an inlet side portion and an outlet side portion. Further, in the check valve according to the first aspect, the valve body is made of a poppet.

[0006]

Next, a check valve according to the present invention will be described in more detail with reference to the drawings showing an embodiment. 1
Is a hollow conduit having an inlet 3 at the left end and an outlet 5 at the right end. The conduit 1 has a front 1 with an inlet 3
a and a rear part 1b provided with an outlet 5. The conduit 1 forms a tapered constriction 4 on the inner peripheral wall of a front part 1 a leading to an inlet 3 and a rear part 1 leading to an outlet 5.
A step 6 having a small diameter is formed on the inner peripheral wall of b. The inner peripheral wall of the conduit 1 between the constriction 4 and the step 6 is formed to have the same diameter,
It has become. A poppet 7 is slidably fitted in the conduit 1 so as to be movable. In the poppet 7, the outer peripheral wall of the front end portion 8 is formed in a shape corresponding to the narrowed portion 4, and the rear end portion 9 is slidably fitted into the step portion 6 so as to be movable. Four ribs 11 for preventing backlash are protruded from a part of the outer periphery of the poppet 7 at equal intervals, and the ribs 11 are slidably contacted with the inscribed portion 2. The rear end 9 is formed in a hollow cylindrical shape, and has a through hole 13 in a part of the peripheral wall. An internal magnet 15 made of a permanent magnet is provided inside the poppet 7. Reference numeral 17 denotes an O-ring provided on the distal end portion 8. An external magnet 19 made of a permanent magnet is provided on the outer periphery of the front portion 1a of the conduit 1 near the front of the center. The internal magnet 15
And the external magnet 19 have different polarities. Reference numeral 21 denotes a screw ring for fixing the external magnet 19. In the figure, 2
Reference numeral 3 denotes an O-ring provided between the front part 1a and the rear part 1b, and arrows indicate the flow direction of a fluid (not shown).

In the above configuration, movement of the poppet 7 and opening and closing of the flow path are as follows. First, the fluid is delivered at a predetermined pressure. At this time, the relationship between the difference (differential pressure) between the pressure A on the inflow port 3 side and the pressure B on the outflow port 5 side and the attracting magnetic force M between the internal magnet 15 and the external magnet 19 is as shown in Table 1.

[0008]

[Table 1]

The pressure A at the inlet 3 is equal to the pressure B at the outlet 5
In the case of a larger value (Table 1), the relationship between the magnetic force and the differential pressure is as follows. That is, the pressure A on the inlet 3 side is a. When the pressure B on the outlet 5 side and the sum of the attractive magnetic force M between the internal magnet 15 and the external magnet 19 are larger than b. When smaller than the above sum, c. It is when it is equal to the above sum. a. In this case, the poppet 7 is pushed by the fluid and moves rightward against the attractive magnetic force M between the internal magnet 15 and the external magnet 19, and the flow path is opened (FIG. 1A). b. In the case described above, when the previous state is open, the poppet 7 moves to the left, and the flow path is closed (FIG. 1B). When the previous state is closed, the poppet 7 does not move and remains closed. That is, the fluid flowing in the opposite direction hits the inner wall 7a of the poppet 7 and presses the poppet 7 in the closing direction. c. In this case, the poppet 7 does not move to the left or right, and the previous state is maintained. That is, when the flow path is closed, it remains closed, and when it is open, it remains open. The relationship between the magnetic force and the differential pressure is as described in a. b.
c. Is determined by appropriately adjusting the magnetic force and the differential pressure.

Next, when the pressure A at the inlet 3 is smaller than the pressure B at the outlet 5 (Table 1), the relationship between the magnetic force and the differential pressure is as follows. Since the pressure is smaller than the sum of the pressure B and the attracting magnetic force M, the poppet 7 moves to the left when the previous state is open, and the flow path is closed (FIG. 1).
B). When the previous state is closed, the poppet 7 does not move and remains closed.

Next, when the pressure A on the inlet 3 side is equal to the pressure B on the outlet 5 side (differential pressure 0, Table 1), the relationship between the magnetic force and the differential pressure becomes small. Is open, it is pulled to the left by the magnetic force M, and the flow path is closed (FIG. 1B). When the previous state is closed, the poppet 7 does not move and remains closed.

Examples are shown in Tables 2 and 3.

[0013]

[Table 2]

[0014]

[Table 3]

As described above, by appropriately adjusting the differential pressure and the magnetic force M, the operating pressure of the valve body can be easily changed, so that it is possible to easily set the operating pressure for various purposes. Become. The adjustment of the magnetic force M is performed by adjusting the distance between the internal magnet 15 and the external magnet 19 and the magnetic force of the internal magnet 15 and the external magnet 19 themselves.

According to the above-described embodiment, there is no possibility that the elastic force is reduced due to the deterioration of the member with the passage of time, so that the reliability and durability of the valve are improved. Also, by adjusting the distance between the internal magnet 15 and the external magnet 19 and the magnetic force of the internal magnet 15 and the external magnet 19 itself, the operating pressure of the valve body can be easily changed. Operating pressure can be set, and versatility is improved. In particular, it is possible to provide a check valve that operates with high reliability even at extremely low operating pressures. For example, even when the capacity of a pump or the like for sending a fluid is small and a conventional check valve is susceptible to the pressure loss of the fluid and cannot flow a desired flow rate,
Such a problem can be prevented. In addition, conduit 1
Can be divided into a front part 1a and a rear part 1b,
Maintenance such as replacement and cleaning of the O-rings 17 and the O-rings 23 is easy. Further, since the internal magnet 15 and the external magnet 19 are made permanent magnets, there is an effect that contributes to downsizing.

The check valve according to the present invention is not limited to the above embodiment. For example, the polarity of the internal magnet 15 and the polarity of the external magnet 19 may be the same, and the repulsive force may be used.

The external magnet 19 may be provided on the inner periphery of the conduit 1 or may be embedded in the conduit 1 depending on the nature of the fluid.

The position of the external magnet 19 is arbitrary, and may be, for example, a position near the center of the conduit 1 at the rear. In this case, the polarities of the inner magnet 15 and the outer magnet 19 are made the same,
Suitable for utilizing its repulsion.

The conduit 1 does not have to be configured to be dividable.

The material constituting each part such as the conduit 1, the poppet 7 and the like is arbitrary.

The shapes of the conduit 1 and the poppet 7 are not limited as long as they can move in one direction. The shape of the tip 8 of the poppet 7 is also arbitrary.

[0023]

As described above, according to the check valve of the present invention, it is possible to improve the reliability of the valve and to ensure the versatility of the valve.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a check valve according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 conduit 1a front part 1b back part 2 inscribed part 3 inflow port 4 constriction part 5 outflow port 6 stepped part 7 poppet 7a inner wall 8 tip part 9 rear end part 11 rib 13 through hole 15 internal magnet 17 O-ring 19 external magnet 21 screw Ring 23 O-ring

Claims (8)

[Claims] 1. A hollow conduit having an inlet at one end and an outlet at the other end, a valve movably provided in the conduit, an external magnet provided in the conduit, and an external magnet provided in the conduit. An internal magnet provided inside, wherein the valve body determines the presence or absence and direction of movement based on the relationship between the differential pressure between the pressure on the outlet side and the pressure on the inlet side and the magnetic force of the inner and outer magnets. Check valve. 2. The check valve according to claim 1, wherein the external magnet and the internal magnet have different polarities. 3. The check valve according to claim 1, wherein the external magnet and the internal magnet have the same polarity. 4. The check valve according to claim 1, wherein the external magnet is provided on an outer periphery of the conduit. 5. The check valve according to claim 1, wherein the external magnet is provided on an inner periphery of the conduit. 6. The check valve according to claim 1, wherein the external magnet is embedded in the conduit. 7. The check valve according to claim 1, wherein said conduit is dividable into an inlet side portion and an outlet side portion. 8. The check valve according to claim 1, wherein the valve body is formed of a poppet.