WO2023113268A1

WO2023113268A1 - Double check valve

Info

Publication number: WO2023113268A1
Application number: PCT/KR2022/018318
Authority: WO
Inventors: 남충우; 이호길; 박장훈
Original assignee: 한국자동차연구원
Priority date: 2021-12-16
Filing date: 2022-11-18
Publication date: 2023-06-22
Also published as: KR102521583B1

Abstract

According to an embodiment of the present disclosure, provided is a check valve comprising: an entrance end (100) in which a fluid flows; an outlet end (111) from which the fluid flowing from the entrance end is discharged; a housing (12) which is between the entrance end (100) and the outlet end (111), allows the fluid to be in communication between the entrance end (100) and the outlet end (111), and has an inclined surface formed in at least part of the inner surface, the diameter of the inclined surface increasing downward from the entrance end (100) to the outlet end (111); an outer valve (200) which is formed in a hollow column shape disposed in the housing (12), and comprises an outer inclined portion (206) formed at the corner of the upper surface and being in contact with the inclined surface of the housing (12), a first through-hole (201) formed from the upper surface, and a second through-hole (203) which is formed in the lower side of the first through-hole (201) and has the diameter greater than the first through-hole (201); and an inner valve (300) which is formed to be at least partially arranged in the outer valve (200), the inner valve (300) comprising a first body portion (301) formed in a column shape having the outer diameter less than the inner diameter of the first through-hole (201), and a second body portion (302) of a column shape which is formed on the lower portion of the first body portion (301), has an inclined surface at the corner of the upper surface, and is restricted from moving upward by the ceiling portion of the second through-hole (203).

Description

double check valve

The present disclosure relates to a double check valve, and more specifically, to a double check valve capable of controlling a flow rate for a pressure section of a supplied fluid even though it has a relatively simple structure.

The content described in this section simply provides background information for the present disclosure and does not constitute prior art.

As shown in FIG. 1, the conventional check valve 1' is inserted into the first housing 10 having an inlet end 100 formed at one end and the first housing 10, and the outlet end 111 is The formed second housing 11, the first housing 10 and the third housing 12 disposed inside the second housing 11, and the valve body 14 disposed inside the third housing 12 and a spring 13 disposed between one surface of the valve body 14 and an inner surface of the third housing 12 .

When a fluid having a pressure higher than a certain pressure is introduced through the inlet end 100, the valve body 14 moves downward and the high-pressure flow hole 120 is opened. The fluid passes through the open high-pressure flow hole 120 and flows through the high-pressure flow path 110 formed between the lower cap 12a of the third housing and the second housing 11 . The fluid passing through the high-pressure flow passage 110 is discharged through the outlet end 111 .

On the other hand, although the first housing 10, the second housing 11, and the third housing 12 of the check valve 1' are all formed and assembled as separate components, they are shown as one component. may consist of

When a high-pressure fluid suddenly passes through the conventional check valve 1', problems such as noise may occur.

In addition, in the case of a check valve applied to a fueling receptacle of a vehicle, specifications for a layout are set. Due to this, it is not easy to change the design for performance improvement. In particular, in the case of a vehicle that runs on hydrogen fuel, it is necessary to endure high-pressure hydrogen when charging hydrogen, so strict standards must be observed.

In addition, there is a problem in that a sealing unit is separately included to ensure airtightness, complicating process procedures, and increasing manufacturing cost.

(Patent Document 1) US 10,767,773 B2

(Patent Document 2) JP 6384370 B2

(Patent Document 2) JP 2021-124049 A

Accordingly, an object of the present disclosure is to provide a check valve that is advantageous for noise in various pressure ranges.

In addition, an object of the present disclosure is to provide a check valve that satisfies the specifications of a check valve for a receptacle while improving its performance.

An object of the present invention is to provide a check valve that does not require a separate sealing device (eg, an O-ring).

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

According to one embodiment of the present disclosure, the inlet end 100 into which the fluid is introduced; an outlet end 111 through which the fluid introduced from the inlet end is discharged; The fluid between the inlet end 100 and the outlet end 111 is communicated between the inlet end 100 and the outlet end 111, and the outlet from the inlet end 100 to at least a part of the inner surface. a housing 12 having an inclined surface whose diameter increases downward in a direction toward the stage 111; As a hollow columnar outer valve 200 disposed inside the housing 12, the outer inclined portion 206 formed at the corner of the upper surface and in contact with the inclined surface of the housing 12; a first through hole 201 formed from the upper surface; and an outer valve 200 including a second through hole 203 formed under the first through hole 201 and having a larger diameter than the first through hole 201; At least a portion of the inner valve 300 configured to be disposed inside the outer valve 200, the columnar first body portion 301 having an outer diameter smaller than the inner diameter of the first through hole 201; A columnar second body portion formed below the first body portion 301 and having an inclined surface formed at the corner of the upper surface and limited in upward movement by the ceiling of the second through hole 203 ( 302) to provide a check valve including an inner valve 300.

Also, preferably, the outer valve 200 of the present disclosure is formed between the first through hole 201 and the second through hole 203, and is configured to increase in inner diameter toward the lower side. 1 includes an inner inclined portion 202, and the inner valve 300 is formed between the first body portion 301 and the second body portion 302, and has an inner diameter that increases as it goes downward. The configured body connection part 303 is included, the height of the first inner inclined part 202 is lower than the height of the body connecting part 303, and the gradient of the first inner inclined part 202 is, the body connecting part 303 ) is less than the gradient of

Also, preferably, the inner valve 300 of the present disclosure includes one or more inlet holes 305 formed from an inclined surface formed at an upper corner of the second body 302 toward the center of the inner valve 300. ); and a third body portion 304 extending from a lower surface of the second body portion 302 and having a low-pressure flow hole 306 formed therein so as to be in fluid communication with the one or more inlet holes 305 .

Also, preferably, the housing 12 of the present disclosure is formed on a side surface and includes one or more high-pressure flow holes 120 formed to face the outer valve 200 .

In addition, preferably, when a fluid having a pressure less than the first pressure is introduced through the inlet end 100 of the present disclosure, the outer inclined portion 206 and the housing 12 are in contact, and the first 1 The inner inclined part 202 and the body connection part 303 come into contact at a first contact point P ₁ , and the ceiling of the second through hole 203 and the body connection part 303 come into contact with each other at a second contact point P ₂ ), and the first pressure is equal to the sum of the frictional force at the first contact point P ₁ and the frictional force at the second contact point P ₂ .

In addition, preferably, when a fluid having a pressure greater than or equal to a first pressure and less than a second pressure greater than the first pressure is introduced through the inlet end 100 of the present disclosure, the outer inclined portion 206 and The housing 12 is in contact, the first inner inclined portion 202 and the body connection portion 303 are spaced apart, and the ceiling portion of the second through hole 203 and the body connection portion 303 are spaced apart, The second pressure is equal to the sum of the frictional force at the outer inclined portion 206 , the frictional force at the first contact point P ₁ , and the frictional force at the second contact point P ₂ .

Also, preferably, when a fluid having a pressure equal to or higher than the second pressure is introduced through the inlet end 100 of the present disclosure, the outer inclined portion 206 and the housing 12 are spaced apart, and the outer valve ( 200) moves downward, the outer inclined portion 206 and the housing 12 are separated, and the fluid introduced through the inlet end 100 flows into the high-pressure flow hole 120.

Also, preferably, the outer valve 200 of the present disclosure includes a groove 204 formed in the ceiling of the second through hole 203, and the groove 204 and the body connection part 303 The shortest distance between the lower edges of is shorter than the shortest distance between the lower edges of the second body part 302 and the body connecting part 303 .

As described above, according to the present embodiment, since the check valve is opened in stages, there is an effect of reducing noise in various pressure ranges.

In addition, as a check valve with a design change applied only to the inside, it has an effect that it can be compatible with all vehicles on the market because its appearance satisfies the standard.

In addition, since sealing is possible using only the contact surfaces such as the outer inclined portion, the first contact point, and the second contact point, there is no need to provide a separate sealing device (eg, O-ring), so the manufacturing is easy and the manufacturing cost is reduced. there is.

1 shows a conventional check valve structure.

2 is a perspective view of an outer valve and an inner valve of a check valve according to an embodiment of the present disclosure.

3 is a cross-sectional and partially enlarged view of a check valve according to an embodiment of the present disclosure.

4a to 4c show the operation sequence of the check valve according to an embodiment of the present disclosure.

Hereinafter, some embodiments of the present disclosure will be described in detail through exemplary drawings. In adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible, even if they are displayed on different drawings. In addition, in describing the present disclosure, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present disclosure, the detailed description will be omitted.

In describing the components of the embodiment according to the present disclosure, symbols such as first, second, i), ii), a), and b) may be used. These codes are only for distinguishing the component from other components, and the nature or sequence or order of the corresponding component is not limited by the codes. In the specification, when a part is said to 'include' or 'include' a certain component, it means that it may further include other components, not excluding other components unless explicitly stated otherwise. .

In the present disclosure, "upward" means the opposite direction to the flow direction when the fluid flows into the check valve 1.

In addition, in the present disclosure, "downward" means a direction in which fluid flows into the check valve 1 when it flows.

In addition, note that "low pressure" and "high pressure" in the present disclosure are intended to indicate relative magnitudes of fluid pressures, and are not absolute values.

In addition, in the present disclosure, the configuration of the check valve 1 except for the outer valve 200 and the inner valve 300 may be the same as the components described in FIG. 1 or may be at a level capable of simple design change. Therefore, in the present disclosure, parts except for the components described in FIG. 1 will be described.

In addition, in FIGS. 4B to 4C , relatively low-pressure fluids are indicated by thin line arrows, and relatively high-pressure fluids are indicated by thick-lined arrows, but this is for convenience of description and understanding. That is, it should not be understood that the low pressure fluid and the high pressure fluid flow separately, and it should be noted that the low pressure fluid and the high pressure fluid may flow in a mixture.

Referring to FIG. 2 , the check valve 1 according to an embodiment of the present disclosure may include an outer valve 200 and an inner valve 300 .

At least a part of the inner valve 300 is inserted into the outer valve 200, and the assembly of the outer valve 200 and the inner valve 300 includes the first housing 10, the second housing 11 and the third housing 10. It may be disposed inside the housing 12 (see FIG. 3).

The outer valve 200 is formed in a substantially hollow column shape, and is formed so that at least a part of the inner valve 300 is inserted therein.

An outer inclined portion 206 is formed at the corner of the upper surface of the outer valve 200. As the outer inclined portion 206 is formed, the outer valve 200 may come into contact with the inner surface of the third housing 12 (see FIG. 3). At this time, it is preferable that the gradient of the outer inclined portion 206 is the same as that of the inner surface of the third housing 12 . Due to this, the fluid flowing through the third housing 12 can be properly sealed without being discharged to the outside of the third housing 12 .

At least a part of the inner valve 300 is inserted into the outer valve 200.

The inner valve 300 includes all or part of the first body part 301, the second body part 302, the body connection part 303, the third body part 304, and the inflow hole 305.

The first body portion 301 has a substantially columnar shape, is disposed at an upper end of the inner valve 300, and is disposed such that at least a portion thereof is surrounded by the outer valve 200.

At the uppermost end of the first body part 301, a truncated cone-shaped column part may be further formed. Due to this, it is possible to guide the flow of the fluid flowing downward to be diffused.

The second body portion 302 is formed below the first body portion 301 and has a larger diameter than the maximum diameter of the first body portion 301 .

A body connection part 303 is disposed between the first body part 301 and the second body part 302 . The body connection portion 303 connects the first body portion 301 and the second body portion 302, and is formed such that its diameter increases downward.

The edge of the body connection part 303 is formed with an inclined surface, and an inlet hole 305 is formed toward the inside of the body connection part 303 from the inclined surface. The inlet hole 305 is preferably arranged in plurality along the circumferential direction of the inclined surface of the body connection part 303 . In the present disclosure, it is illustrated that four inlet holes 305 are formed, but it is not necessarily limited thereto, and the design may be appropriately changed according to the target blocking hydraulic pressure and flow rate.

The third body portion 304 is formed to extend from the lower surface of the second body portion 302 . A low pressure flow hole 306 (see FIG. 3 ) through which the fluid introduced from the inlet hole 305 can flow may be formed inside the third body part 304 .

In the check valve 1 according to an embodiment of the present disclosure, when fluid having a pressure lower than the first pressure flows in, the outer valve 200 and the inner valve 300 do not move. Hereinafter, this state is referred to as an unopened state.

When a fluid having a pressure higher than the first pressure and lower than the second pressure is introduced, the outer valve 200 and the inner valve 300 slightly move downward. Hereinafter, this state is referred to as an open state of the inner valve 300 . Meanwhile, the second pressure means a pressure greater than the first pressure.

When a fluid having a pressure equal to or higher than the second pressure is introduced, both the outer valve 200 and the inner valve 300 move downward with the inner valve 300 open. Hereinafter, this state is referred to as a state in which both the inner valve 300 and the outer valve 200 are open.

Referring to Figure 3, the configuration and shape of the check valve 1 according to an embodiment of the present disclosure will be described in detail. The check valve 1 includes all or part of the first housing 10, the second housing 11, the third housing 12, the spring 13, the outer valve 200 and the inner valve 300. do.

Meanwhile, the description of the first housing 10, the second housing 11, the third housing 12, and the spring 13 is replaced with the description in FIG.

The assembly of the outer valve 200 and the inner valve 300 is disposed inside the third housing 12 .

The outer valve 200 and the inner valve 300 are preferably formed of different materials. For example, the outer valve 200 is composed of polyamide-imide or PEEK, and the inner valve 300 is preferably formed of a material having strong durability against hydrogen embrittlement. . At this time, an example of a material having strong durability against hydrogen embrittlement may include SUS316L, and the content of nickel (Ni) may be increased depending on the use of the receptacle to which the check valve 1 is applied.

As the outer valve 200 and the inner valve 300 are formed of different materials, an appropriate friction force may be formed between the outer valve 200 and the inner valve 300 .

Inside the outer valve 200, a first through hole 201, a first inner inclined portion 202, a second through hole 203, and a second inner inclined portion 205 are sequentially formed.

At least a part of the inner valve 300 may be inserted into the first through hole 201 .

The first inner inclined portion 202 extends from the first through hole 201 and increases in diameter as it goes downward. At this time, the inclination of the first inner inclined portion 202 is referred to as a ₁ .

The second through hole 203 extends from the end of the first inner inclined portion 202 and is larger than the maximum diameter of the first inner inclined portion 202 .

At this time, a groove 204 is formed in the ceiling portion where the second through hole 203 is formed. The groove 204 is formed in a direction from the ceiling where the second through hole 203 is formed toward the top.

The fluid that has sequentially passed through the first through hole 201 and the first inner slope 202 may flow into the second through hole 203 (see FIG. 4B ). Meanwhile, a boundary surface is formed at a corner of the second body portion 302, so that a vortex forming portion 207, which is a predetermined space, is formed between the second through hole 203 and the second body portion 302.

As a vortex is generated in the vortex forming unit 207, the fluid is pushed by the swirling force of the fluid and flows into the inlet hole 305. However, at the time when the inner valve 300 moves downward, that is, in the initial stage when the contact points of the inner valve 300 and the outer valve 200 start to open, most of the vortex forming part 207 is the dead volume (dead volume). Specifically, in the initial stage when the valve starts to open, the fluid flows along the surface of the first body portion 301, but it is difficult to form a vortex in the vortex forming portion 207.

At this time, if the groove 204 is formed, the fluid may spread widely to the vortex forming unit 207 as a vortex is formed through the groove 204 even at the initial stage when the inner valve 300 is opened.

Due to this, the dead volume of the vortex forming unit 207 is reduced and the vortex forming unit 207 is fully utilized, so that the force pushing the inner valve 300 downward increases.

The groove 204 is preferably formed near a point where the boundary of the second body portion 302 and the upper surface of the second through hole 203 start to be separated. Due to this, the vortex formed in the groove 204 may be diffused to the vortex forming unit 207 in the widest possible vicinity.

Meanwhile, in the present disclosure, the cross section of the groove 204 is illustrated as being triangular, but this is only exemplary, and the shape of the cross section may be appropriately designed and changed by a user.

The second inner inclined portion 205 is formed by being connected to the lower end of the second through hole 203 . The second inner inclined portion 205 may be formed to increase in diameter as it goes downward. As the second inner inclined portion 205 is formed, assembly of the outer valve 200 and the inner valve 300 may be facilitated.

An outer inclined portion 206 is formed outside the outer valve 200 . The outer inclined portion 206 is formed at the corner of the upper surface of the outer valve 200 and contacts one surface of the upper cap 12b of the third housing (see enlarged view).

Depending on the contact area of the outer inclined portion 206, the magnitude of the second pressure may be determined. Specifically, when the contact area of the outer inclined portion 206 increases, the frictional force formed between the outer valve 200 and the upper cap 12b of the third housing increases. The outer valve 200 can be opened only when an external pressure equal to or greater than this frictional force is provided.

Therefore, the area of the outer inclined portion 206 can be appropriately determined in consideration of the purpose of the receptacle to which the check valve 1 is applied and the target blocking pressure.

On the other hand, the inner diameter of the upper cap 12b of the third housing is formed to decrease in an upward direction near the outer inclined portion 206 and the upper cap 12b of the third housing. Due to this, the outer valve 200 does not move upward to the point where the outer inclined portion 206 abuts, so that it can serve as a check valve.

At least a part of the inner valve 300 is formed and arranged so as to be surrounded by the outer valve 200 .

The inner valve 300 has a first body part 301, a second body part 302, a body connection part 303, a third body part 304, an inlet hole 305, and a low pressure flow hole 306. include all or part of

At least a portion of the first body portion 301 may be surrounded by the outer valve 200 . At this time, the outer diameter of the first body portion 301 is smaller than the inner diameter of the first through hole 201 . Due to this, a gap, that is, a flow path may be formed between the first through hole 201 and the first body portion 301, and the fluid may flow through the gap.

The second body portion 302 is formed to have a larger diameter than the diameter of the first body portion 301 . At this time, an inclined surface may be formed at the corner of the upper surface of the second body portion 302 .

The body connecting portion 303 connects both of the first body portion 301 and the second body portion 302, but is formed to increase in diameter as it goes downward.

The height of the body connection part 303 is formed higher than the height of the first inner inclined part 202 .

The inclination gradient (α ₁ ) of the body connection part 303 is greater than the inclination gradient (α ₂ ) of the first inner inclination part 202 . That is, the inclination of the body connection part 303 is steeper than the inclination of the first inner inclination part 202 . Due to this, the outer valve 200 and the inner valve 300 are primarily in contact at the first contact point P ₁ .

In addition, the second body portion 302 and the first inner inclined portion 202 are in second contact at the second contact point P ₂ . Thus, the space between the outer valve 200 and the inner valve 300 can be sealed twice.

As described above, the outer valve 200 and the inner valve 300 may be formed of different materials. Appropriate frictional force is formed at the first contact point P ₁ , and the flowing fluid may be sealed. That is, since there is a sealing effect between the outer valve 200 and the inner valve 300 only with the structure and material, there is no need to add a separate sealing part (eg, O-ring), thereby reducing costs.

The minimum diameter of the second body portion 302 is larger than the diameter of the hole at the connection point between the first inner inclined portion 202 and the second through hole 203 . Due to this, upward movement of the second body portion 302 may be restricted. That is, the upward movement of the inner valve 300 is restricted, so that it can serve as a check valve.

The third body portion 304 is formed to extend from the lower surface of the second body portion 302 . The diameter of the third body part 304 may be smaller than the maximum diameter of the second body part 302 . For this reason, the spring 13 may be disposed in the step formed between the second body part 302 and the third body part 304 .

The inlet hole 305 is formed in a direction toward the inside of the inner valve 300 from the inclined surface formed at the corner of the second body portion 302 . When a fluid having a certain pressure or more is introduced through the inlet end 100, the inner valve 300 slightly moves downward, and the outer valve 200 and the inner valve 300 are separated from each other. The fluid passing through the gap between the spaced outer valve 200 and the inner valve 300 may flow into the inlet hole 305 .

The low pressure flow hole 306 is formed in fluid communication with one or more inlet holes 305 . The low-pressure flow hole 306 is formed inside the third body portion 304 and may extend into the second body portion 302 in some cases.

The low pressure flow hole 306 extends to the lower surface of the third body portion 304 . The fluid flowing into the inner valve 300 through the inflow hole 305 passes through the low pressure flow hole 306 and through the opening of the third body 304, and is discharged to the outside of the inner valve 300. It can be.

In FIG. 4A , a state in which fluid does not flow through the inlet end 100 or a fluid having a pressure less than the first pressure is provided is illustrated. Even if the fluid having a pressure less than the first pressure pressurizes the outer valve 200 and the inner valve 300, the outer valve 200 and the inner valve formed at the first contact point P ₁ and the second contact point P ₂ Due to the friction between the parts 300, the inner valve 300 may not move.

In addition, the outer valve 200 may not move due to frictional force generated when the outer inclined portion 206 contacts the upper cap 12b of the third housing.

That is, both the outer valve 200 and the inner valve 300 are not opened due to the frictional force formed by the outer inclined portion 206, the first contact point P ₁ and the second contact point P ₂ .

In FIG. 4B , a state in which fluid having a pressure equal to or greater than the first pressure and less than the second pressure is introduced through the inlet 100 is shown. At this time, the first pressure is equal to or greater than the sum of the frictional force formed by the first contact point P ₁ and the frictional force formed by the second contact point P ₂ . However, the second pressure is less than the sum of the frictional force formed by the first contact point P ₁ , the frictional force formed by the second contact point P ₂ , and the frictional force formed by the outside inclined portion 206. corresponds to the value

The introduced fluid pressurizes the outer valve 200 and the inner valve 300 . The inner valve 300 moves slightly downward by the hydraulic pressure, and the outer valve 200 does not move. As the flow path leading to the inlet hole 305 is opened, the low-pressure fluid passes through the gap formed between the inner valve 300 and the first body beam, passes through the inlet hole 305 and the low-pressure flow hole 306, and exits. It is discharged to the outside of the check valve 1 through the stage 111.

In FIG. 4C , a state in which fluid having a pressure equal to or higher than the second pressure is introduced through the inlet end 100 is illustrated.

The introduced fluid pressurizes the outer valve 200 and the inner valve 300 . Both the inner valve 300 and the outer valve 200 are moved downward by the hydraulic pressure. This is because the second pressure is the sum of the frictional force formed by the first contact point P ₁ , the frictional force formed by the second contact point P ₂ , and the frictional force formed by the external inclined portion 206. possible.

When the outer valve 200 is opened, it sequentially passes through the high-pressure flow hole 120 and the high-pressure flow path 110 and joins the fluid passing through the low-pressure flow hole 306 .

4A to 4C, in the check valve 1 according to the present disclosure, the inner valve 300 is primarily opened in a relatively low pressure section, and the outer valve 200 is secondarily opened in a relatively high pressure section. ) and the inner valve 300 may both be opened. Due to this, noise due to chattering can be more effectively prevented than when the check valve is opened by the high-pressure fluid at once.

The above description is merely an example of the technical idea of the present embodiment, and various modifications and variations can be made to those skilled in the art without departing from the essential characteristics of the present embodiment. Therefore, the present embodiments are not intended to limit the technical idea of the present embodiment, but to explain, and the scope of the technical idea of the present embodiment is not limited by these embodiments. The scope of protection of this embodiment should be construed according to the claims below, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of rights of this embodiment.

1: check valve

10: first housing

11: second housing

12: third housing

13: spring

200: outer valve

300: inner valve

Claims

An inlet end 100 through which fluid is introduced;

an outlet end 111 through which the fluid introduced from the inlet end is discharged;

The fluid between the inlet end 100 and the outlet end 111 is communicated between the inlet end 100 and the outlet end 111, and the outlet from the inlet end 100 to at least a part of the inner surface. a housing 12 having an inclined surface whose diameter increases downward in a direction toward the stage 111;

As a hollow columnar outer valve 200 disposed inside the housing 12,

an outer inclined portion 206 formed at a corner of the upper surface and in contact with the inclined surface of the housing 12;

a first through hole 201 formed from the upper surface; and

an outer valve 200 formed below the first through hole 201 and including a second through hole 203 having a larger diameter than the first through hole 201;

As the inner valve 300, at least a part of which is configured to be disposed inside the outer valve 200,

a columnar first body portion 301 having an outer diameter smaller than an inner diameter of the first through hole 201;

A columnar second body portion formed below the first body portion 301 and having an inclined surface formed at the corner of the upper surface and limited in upward movement by the ceiling of the second through hole 203 ( Inner valve 300 including 302)

including,

check valve.
According to claim 1,

The outer valve 200 is formed between the first through hole 201 and the second through hole 203, and includes a first inner inclined portion 202 configured to increase in inner diameter toward the lower side. do,

The inner valve 300 is formed between the first body portion 301 and the second body portion 302, and includes a body connection portion 303 configured to increase in inner diameter toward the bottom,

The height of the first inner inclined portion 202 is lower than the height of the body connection portion 303,

The gradient of the first inner inclined portion 202 is smaller than the gradient of the body connection portion 303,

check valve.
According to claim 2,

The inner valve 300,

one or more inflow holes 305 formed from an inclined surface formed at a corner of an upper surface of the inner valve 300 toward the center of the inner valve 300; and

A third body portion 304 extending from the lower surface of the second body portion 302 and having a low-pressure flow hole 306 formed therein so as to be in fluid communication with the one or more inflow holes 305

including,

check valve.
According to claim 3,

The housing 12 is formed on a side surface and includes one or more high-pressure flow holes 120 formed to face the outer valve 200.

check valve.
According to claim 4,

When a fluid having a pressure less than the first pressure is introduced through the inlet end 100,

The outer inclined portion 206 and the housing 12 are in contact,

The first inner inclined portion 202 and the body connection portion 303 are in contact at a first contact point P 1 ,

The ceiling portion of the second through hole 203 and the body connection portion 303 are in contact at a second contact point P 2 ,

The first pressure is equal to the sum of the frictional force at the first contact point P 1 and the frictional force at the second contact point P 2 ,

check valve.
According to claim 5,

When a fluid having a pressure greater than the first pressure and less than the second pressure greater than the first pressure is introduced through the inlet end 100,

The outer inclined portion 206 and the housing 12 are in contact,

The first inner inclined portion 202 and the body connection portion 303 are spaced apart,

The ceiling portion of the second through hole 203 and the body connection portion 303 are spaced apart,

The second pressure is equal to the sum of the frictional force at the outer inclined portion 206, the frictional force at the first contact point P 1 and the frictional force at the second contact point P 2 ,

check valve.
According to claim 6,

When a fluid having a pressure equal to or higher than the second pressure is introduced through the inlet end 100,

The outer inclined portion 206 and the housing 12 are spaced apart, and the outer valve 200 moves downward, thereby separating the outer inclined portion 206 and the housing 12,

The fluid introduced through the inlet end 100 flows into the high pressure flow hole 120,

check valve.
According to claim 2,

The outer valve 200 includes a groove 204 formed in the ceiling of the second through hole 203,

The shortest distance between the groove 204 and the lower edge of the body connection part 303 is shorter than the shortest distance between the second body part 302 and the lower edge of the body connection part 303,

check valve.