CN220505908U

CN220505908U - Novel high clean gas relief pressure valve

Info

Publication number: CN220505908U
Application number: CN202321997322.9U
Authority: CN
Inventors: 王贤松; 龚如意; 胡跃钢
Original assignee: Gentec Shanghai Corp
Current assignee: Gentec Shanghai Corp
Priority date: 2023-07-27
Filing date: 2023-07-27
Publication date: 2024-02-20
Anticipated expiration: 2033-07-27

Abstract

The utility model discloses a novel high-clean gas pressure reducing valve which comprises a valve body, a valve rod, a diaphragm assembly, a valve cover and an upper cover, wherein the valve body is provided with an air outlet cavity, an air inlet and an air outlet which are communicated with the air outlet cavity, an inlet cavity and a valve core cavity are sequentially arranged between the air inlet and the air outlet cavity, and a diaphragm sealing surface is arranged at the top of the air outlet cavity. The valve rod reset spring is arranged in the spring cavity on the basis of the existing high-cleanness pressure reducing valve, and the valve rod is lifted through the diaphragm assembly, so that the valve rod reset spring is prevented from being detained in the flow passage, and the cleanliness of the valve is prevented from being influenced. In addition, an anti-loosening device is further added to prevent the anti-loosening problem after the valve rod is connected with the diaphragm assembly. After the collecting cavity is completely closed, the collecting cavity can be used as a DOM cavity of the DOM pressure reducing valve, and the output pressure of the pressure reducing valve can be remotely controlled by loading air pressure to the DOM cavity, so that the function of the pressure reducing valve is improved.

Description

Novel high clean gas relief pressure valve

Technical Field

The utility model relates to the field of valves, in particular to a novel high-clean gas pressure reducing valve.

Background

In the process of ion implantation, deposition, diffusion, etching and the like in semiconductor manufacturing, various control valves are needed to control the high-purity or ultra-high-purity gases in order to ensure the product quality. To prevent the electron gas from being polluted during the gas transportation, the control valves and the equipment all meet the requirement of high cleanliness.

In order to meet the requirement of high cleanliness, the valve element has no pollution or little pollution, or the flow passage surface is smooth, and the flow passage is simple, free of stagnation and convenient to purge and clean. The high clean valve generally adopts a stainless steel diaphragm valve structure without sealing, has no sealing friction pair and has no pollution caused by relative friction.

The high clean gas pressure reducing valve also adopts a stainless steel diaphragm type structure, and compared with a common diaphragm valve, the internal structure of the high clean gas pressure reducing valve is more complex, as shown in figure 1. In order to reduce pollution, stagnation is reduced in the flow channel, and stagnation surfaces such as the thread surfaces are isolated or hidden in the closed containing cavity, so that the influence of threads on fluid stagnation is reduced, and the flow channel is convenient to purge and remove surface particles. However, the valve rod reset spring is still in the flow channel, the shape of the spring is irregular, particles are easy to stay, the purging effect is affected, and residual particles are not easy to blow clean. In addition, the valve rod is only supported by the reset spring and is simply in threaded connection with the diaphragm assembly, no effective anti-loosening measures exist, and the risk of loosening the valve rod exists.

In addition, because the electronic gas is inflammable and explosive, any leakage has potential accident risk, the spring cavity at the upper part of the diaphragm of the pressure reducing valve is used as a collecting cavity for collecting the escaping gas, so that the gas is prevented from escaping during faults, and the gas possibly escaping is led out to the outdoor or special collecting and processing equipment through a pipeline. The existing structure can not completely lead out the escaping gas, and the leakage from the connection is still risked.

In terms of the stainless steel diaphragm sealing structure, the diaphragm sealing surface on the valve body is exposed, so that the production process is easy to be knocked and damaged, the sealing surface is invalid, leakage is generated, the sealing effect is affected, and the control difficulty of the manufacturing process is increased.

Aiming at the problems, a novel high-clean gas pressure reducing valve is invented.

Disclosure of Invention

Aiming at the defects of the prior art, the utility model provides a novel high-cleanness gas pressure reducing valve, which moves a reset spring to the outside of a flow channel to reduce the influence of the reset spring on cleanliness; a sealing ring is added to completely seal the collecting cavity; the novel stainless steel diaphragm sealing structure protects the diaphragm sealing surface on the valve body, prevents the sealing surface from being bumped in the production process, and solves the problems in the background art.

In order to achieve the above purpose, the utility model is realized by the following technical scheme: a novel high clean gas pressure reducing valve, comprising:

the valve body is provided with an air outlet cavity, an air inlet and an air outlet which are communicated with the air outlet cavity, an inlet cavity and a valve core cavity are sequentially arranged between the air inlet and the air outlet cavity, and a diaphragm sealing surface is arranged at the top of the air outlet cavity;

the valve rod is arranged in the air inlet cavity, and the two ears of the valve rod are clamped with the double concave ear grooves in the air inlet cavity;

the valve seat assembly is screwed into the valve core cavity and comprises valve seat seals and valve seat screws, the valve seat seals are sealed with the step end face of the valve core cavity, a taper hole of the valve seat seals is attached to a taper head of the valve rod, and a valve port is formed between the taper hole and the taper head;

the diaphragm assembly comprises a lifting screw rod, a corrugated stainless steel diaphragm and a lifting nut which are sequentially arranged from top to bottom, a diaphragm blocking sleeve is sleeved on the lifting screw rod, the corrugated stainless steel diaphragm covers the diaphragm sealing surface, and a screw hole of the lifting nut is connected with a threaded rod at the top of the valve rod;

the valve cover with the sealing ring is in butt joint connection with the air outlet cavity of the valve body through a screw cap, a return spring is arranged in the inner cavity of the valve cover, a flange side cover of a cup opening of the diaphragm retaining sleeve is erected on the return spring, and a limit nut in the diaphragm retaining sleeve is connected with the lifting screw;

the upper cover is in threaded connection with the valve cover, an adjusting spring is arranged in the diaphragm retaining sleeve, a spring cover is arranged at the top of the adjusting spring in a supporting mode, and an adjusting device connected with the spring cover is arranged at the top of the upper cover.

Further limited, the novel high clean gas pressure reducing valve is characterized in that an annular protection edge is arranged on the outer side of the sealing surface of the diaphragm.

Further limited, the novel high clean gas pressure reducing valve is characterized in that sealing rings are arranged at the joint of the upper cover and the valve cover and between the spring cover and the upper cover.

Further limited, the novel high clean gas pressure reducing valve is characterized in that a DOME pressure cavity is formed in the inner cavity of the valve cover and the inner cavity of the upper cover, and a DOME pressure control port is formed at the side surface of the upper cover and a screw hole outlet connected with the DOME pressure cavity.

Further limited, the novel high clean gas pressure reducing valve, wherein, the corrugated stainless steel diaphragm, the lifting screw and the lifting nut are welded into a whole, the lower part of the lifting screw is a disc, the center of the upper part is a screw, the top of the screw is provided with a straight groove, and the center of the lifting nut is provided with a straight threaded hole.

Further limited, the novel high clean gas pressure reducing valve is characterized in that the diaphragm retaining sleeve is cup-shaped, the cup opening is provided with a flange, and a through hole for the lifting screw rod to pass through is formed in the center of the diaphragm retaining sleeve.

Further limiting, the novel high clean gas pressure reducing valve is characterized in that the valve cover is a rotary body with a transparent center, an inner hole at the upper end of the valve cover is provided with an inner thread, a sealing groove is arranged outside the inner thread, flange edges are arranged on the inner side and the outer side of the lower end of the valve cover, a sealing groove is arranged on the outer edge end face of the lower end of the valve cover, and a sealing ring matched with a screw cap is arranged in the sealing groove.

Further limiting, the novel high-clean gas pressure reducing valve is characterized in that the upper cover is in an inverted cup shape, the opening at the lower part of the upper cover is provided with a countersink cavity, the outer edge of the lower part of the upper cover is provided with threads and flange edges, a sealing groove is arranged between the threads and the flange edges, the upper bottom is thickened, the center is provided with an adjusting threaded hole, and the side surface of the countersink cavity is provided with the threaded hole.

Further limited, the novel high clean gas pressure reducing valve comprises a knob and an adjusting screw, wherein the adjusting screw penetrates through the upper cover and is connected with the spring cover.

Further limited, the novel high-clean gas pressure reducing valve is characterized in that the spring cover is disc-shaped with a boss in the center, and a sealing groove is formed in the outer edge of the spring cover.

The utility model has the following beneficial effects: according to the utility model, the valve rod and the valve core cavity of the valve body are matched with the double concave ear grooves and double ears, so that the valve rod can be effectively prevented from loosening during working; the annular protection edge of the valve body can effectively protect the sealing surface in the production process; the diaphragm assembly, the diaphragm retaining sleeve, the valve cover and the return spring structure are arranged outside the flow passage, so that the pollution of the return spring of the pressure reducing valve to high-purity gas can be avoided, the pressure reducing valve can be conveniently purged during use, and the cleaning treatment of the return spring with complex structure is also avoided.

The DOME pressure cavity and the DOME pressure control port can control output pressure through external loading pressure, so that the function of the pressure reducing valve is increased; the DOME pressure cavity and the DOME pressure control port can also be used as a collecting cavity, so that the gas escaping after the fatigue fracture of the diaphragm can be effectively collected, and the escaping gas is led out to a safety zone. Is suitable for conveying dangerous gases with extremely toxicity, harm, flammability and explosiveness, and improves the safety.

The valve rod is lifted by the diaphragm assembly, so that the valve rod return spring is prevented from being detained in the flow passage and the cleanliness of the valve is prevented from being influenced. In addition, an anti-loosening device is further added to prevent the anti-loosening problem after the valve rod is connected with the diaphragm assembly. After the collecting cavity is completely closed, the collecting cavity can be used as a DOM cavity of the DOM pressure reducing valve, and the output pressure of the pressure reducing valve can be remotely controlled by loading air pressure to the DOM cavity, so that the function of the pressure reducing valve is improved. The novel valve body upper diaphragm sealing surface outer ring is additionally provided with the protection ring, so that the problem that the valve body upper diaphragm sealing surface is directly exposed outside can be effectively reduced, the control difficulty of the manufacturing process is reduced, and the production cost is reduced.

Drawings

FIG. 1 is a schematic diagram of a conventional high clean gas pressure reducing valve;

FIG. 2 is a cross-sectional view of the present utility model;

FIG. 3 is an exploded view of the present utility model;

FIG. 4 is a cross-sectional view of a valve body of the present utility model;

FIG. 5 is a side view and a cross-sectional view of a valve stem of the present utility model;

FIG. 6 is a cross-sectional view of a diaphragm assembly of the present utility model;

fig. 7 is a schematic diagram of the operation of the present utility model.

In the figure: 1. a valve body; 1-1, an air inlet; 1-2, an air outlet; 1-3, valve core cavity; 1-4, entering a cavity; 1-5, an air outlet cavity; 1-6, sealing surface of diaphragm; 1-7, annular guard edges; 1-8, double concave ear grooves; 2. a valve seat assembly; 2-1, valve seat screw; 2-2, sealing the valve seat; 3. a valve stem; 3-1, a conical head; 3-2, thin rods; 3-3, double ears; 3-4, threaded rod; 4. a diaphragm assembly; 4-1, corrugated stainless steel diaphragm; 4-2, lifting the screw rod; 4-3, lifting the nut; 5. a diaphragm sleeve; 6. a valve cover; 7. a screw cap; 8. an upper cover; 9. a spring cover; 10. a limit nut; 11. a return spring; 12. an adjusting device; 13. an adjusting spring; 14. a seal ring; 15. a DOME pressure chamber; 16. a DOME pressure control port; 17. the valve port.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Referring to fig. 2-7, the present utility model provides a technical solution: a novel high clean gas pressure reducing valve comprises the following components:

the valve body 1, as shown in figure 4, the valve body 1 is cylindrical, the valve body 1 is provided with an air outlet cavity 1-5, an air inlet 1-1 and an air outlet 1-2 which are communicated with the air outlet cavity 1-5, an inlet cavity 1-4 and a valve core cavity 1-3 are sequentially arranged between the air inlet 1-1 and the air outlet cavity 1-5, a diaphragm sealing surface 1-6 is arranged at the top of the air outlet cavity 1-5, and compared with the conventional valve body 1, a circle of annular guard edges 1-7 are additionally arranged at the outer side of the position of the diaphragm sealing surface 1-6, so that the sealing surface can be effectively protected from collision in the production process; the bottom of the inlet cavity 1-4 at the lower part of the valve core cavity 1-3 is provided with a double concave ear groove 1-8;

the valve rod 3, as shown in figure 5, the valve rod 3 is arranged in the air inlet cavity, the upper part of the valve rod 3 is a thin rod 3-2, the top is provided with a threaded rod 3-4, the bottom of the suction rod is provided with a conical head 3-1, the bottom of the conical head 3-1 is provided with double ears 3-3, and the double ears 3-3 are clamped with the double concave ear grooves 1-8 to prevent the valve rod 3 from rotating;

the valve seat assembly 2 is screwed into the valve core cavity 1-3, the valve seat assembly 2 comprises a valve seat seal 2-2 and a valve seat screw 2-1, the valve seat screw 2-1 adopts a screw plug type screw with a through center, an air groove is formed in the upper part of the valve seat screw, a conical surface flaring valve seat seal 2-2 is additionally arranged at the bottom opening of the valve seat seal 2-2), and the conical surface of the valve seat seal 2-2 is downwards sleeved into a counter bore at the lower part of the valve seat. After the valve seat seal 2-2 is acted by the air inlet pressure, the valve seat seal 2-2 is expanded outwards, so that the valve seat seal is beneficial to sealing, the valve seat seal 2-2 is sealed with the step end face of the valve core cavity 1-3, the threads of the valve seat screw 2-1 are closed and completely isolated from a flow passage, a taper hole of the valve seat seal 2-2 is attached to the taper head 3-1 of the valve rod 3, and a valve port 17 is formed between the taper hole and the taper head 3-1.

The diaphragm assembly 4, as shown in fig. 6, comprises a lifting screw 4-2, a corrugated stainless steel diaphragm 4-1 and a lifting nut 4-3 which are sequentially arranged from top to bottom, the corrugated stainless steel diaphragm 4-1, the lifting screw 4-2 and the lifting nut 4-3 are welded into a whole, the lower part of the lifting screw 4-2 is a disc, the center of the upper part is a screw, the top of the screw is provided with a straight slot, the center of the lifting nut 4-3 is provided with a straight thread, the lifting screw 4-2 is sleeved with a diaphragm retaining sleeve 5, the diaphragm retaining sleeve 5 is cup-shaped, the cup mouth is provided with a flange edge, the center of the diaphragm retaining sleeve 5 is provided with a through hole for the lifting screw 4-2 to pass through, the corrugated stainless steel diaphragm 4-1 is covered on the diaphragm sealing surface 1-6, a screw hole of the lifting nut 4-3 is in threaded connection with the top of the valve rod 3, and the diaphragm assembly 4 is rotated to lift the valve rod 3 until the conical head 3-1 of the valve rod 3 is effectively attached to the conical top of the conical hole of the valve seat seal 2-2 of the valve seat assembly 2.

The valve cover 6 with seal ring 14, valve cover 6 adopts the central penetrating revolution body, the upper end inner hole of valve cover 6 sets up the internal thread, the outside of internal thread sets up the seal groove, the inside and outside of the lower end of valve cover 6 all has flange edges, the outer edge end surface of valve cover 6 lower extreme sets up the seal groove, there is seal ring 14 cooperating with nut 7 in the seal groove, go out the gas cavity 1-5 butt joint with valve body 1 through nut 7, screw up nut 7, apply certain moment of torsion, ensure the seal between diaphragm and seal surface, the inner chamber of valve cover 6 has reset spring 11, the flange edge cover of the opening of diaphragm shield 5 cup is set up on reset spring 11, the stop nut 10 in the diaphragm shield 5 is connected with lifting screw 4-2;

the upper cover 8 is in an inverted cup shape and is in threaded connection with the valve cover 6, a sinking cavity is formed in an opening in the lower portion of the upper cover 8, threads and flange edges are arranged on the outer edge of the lower portion of the upper cover 8, a sealing groove is formed between the threads and the flange edges, the upper bottom is thickened, an adjusting threaded hole is formed in the center of the upper cover 8, a threaded hole is formed in the side face of the sinking cavity, an adjusting spring 13 is arranged in the diaphragm retaining sleeve 5, a spring cover 9 is arranged on the top of the adjusting spring 13 in a supporting mode, the spring cover 9 is in a disc shape with a boss in the center, a sealing groove is formed in the outer edge of the spring cover 9, DOME pressure cavities 15 are formed in the inner cavities of the valve cover 6 and the upper cover 8, a DOME pressure control port 16 is formed in the joint of the side face of the upper cover 8 and the valve cover 6, a sealing ring 14 is arranged between the spring cover 9 and the upper cover 8, an adjusting device 12 connected with the spring cover 9 is arranged on the top of the upper cover 8, the adjusting device 12 comprises a knob and an adjusting screw rod, and the adjusting screw rod penetrates through the upper cover 8 and is connected with the spring cover 9.

The valve body 1, the valve seat assembly 2, the valve rod 3 and the diaphragm assembly 4 form a concise internal flow passage, a stagnation area is avoided, purging and cleaning are facilitated, the requirement of high cleanliness is met, and conveyed gas is not polluted.

When the diaphragm retaining sleeve 5 is installed, the reset spring 11 is firstly placed in the inner cavity of the valve cover 6, then the diaphragm retaining sleeve 5 is sleeved on the lifting screw 4-2 of the diaphragm assembly 4, the flange edge of the cup opening of the diaphragm retaining sleeve 5 is covered on the reset spring 11, the diaphragm retaining sleeve 5 is pressed down, the reset spring 11 is compressed, the nut is screwed on to fix the reset spring 11, the reset spring 11 is loaded, and a reset force is transmitted to the valve rod 3 through the diaphragm retaining sleeve 5; in order to prevent the rotation of the nut, the lifting screw 4-2) is driven to rotate, a tool can be inserted into a straight groove at the end part of the upper lifting screw 4-2, and the upper lifting screw 4-2 is fixed to prevent the rotation.

Then the adjusting spring 13 is arranged in the diaphragm retaining sleeve 5, the spring cover 9 with the sealing ring 14 is arranged on the upper part of the adjusting spring 13, the sealing ring 14 is sleeved on the upper cover 8, and then the adjusting spring is screwed into the valve cover 6 for fixation, and finally the adjusting device 12 is installed.

In addition, the sealing ring 14 completely seals the spring cavity closed by the diaphragm assembly 4, the valve cover 6, the valve body 1, the upper cover 8 and the spring cover 9 to form a DOME pressure cavity 15, and a screw hole outlet on the side surface of the upper cover 8 is a DOME pressure control port 16 for externally loading and controlling output pressure so as to increase the control function of the pressure reducer. The device can also be used as a collecting cavity to effectively collect the gas which escapes after the fatigue fracture of the diaphragm, and the escaping gas is led out to a safety area.

In operation, as shown in fig. 7, the rotation adjusting device 12 pushes the spring cover 9, compresses the adjusting spring 13, and then opens the valve rod 3 through the diaphragm retaining sleeve 5 and the diaphragm assembly 4 to set output pressure.

The high-pressure gas is connected from the gas inlet 1-1, enters the gas inlet cavity, enters the gas outlet cavity 1-5 through the valve port 17, acts under the diaphragm assembly 4 after the pressure in the gas outlet cavity 1-5 rises, generates upward thrust, counteracts the force of the loaded regulating spring 13 through the diaphragm retaining sleeve 5, and pulls the valve rod 3 to reset by the lifting nut 4-3 until the pressure in the gas outlet cavity 1-5 rises enough, and closes the valve port 17. When the pressure of the air outlet cavity 1-5 is reduced, the thrust acting under the diaphragm assembly 4 is reduced, the force of the regulating spring 13 pushes the valve rod 3 downwards to open the valve port 17, dynamic balance is achieved, and finally the output pressure is stabilized in a certain range and is output from the air outlet 1-2.

The reset spring 11 is supported on the inner flange edge of the lower end of the valve cover 6, and provides an upward lifting reset force for the diaphragm assembly 4 through the diaphragm retaining sleeve 5 and the nut, the valve rod 3 is pulled to reset by the lifting nut 4-3, and when the output pressure is not set by the regulating device 12, the valve is closed.

Because the flow passage inside the valve is concise, no stagnation area and no cleaning blind area exist, the high-purity gas can conveniently reach the requirement of high cleanliness after being purged, and the high-purity gas can not be polluted after passing through the valve and still keeps a high-cleanliness state.

According to the utility model, the valve rod 3 and the valve core cavity 1-3 of the valve body 1 are matched with the double concave ear grooves 1-8 and the double ears 3-3, so that the valve rod 3 can be effectively prevented from loosening during working; the annular protective edges 1-7 of the valve body 1 can effectively protect the sealing surface in the production process; the diaphragm assembly 4, the diaphragm baffle sleeve 5, the valve cover 6 and the reset spring 11 are of a structure, the reset spring 11 is arranged outside the flow passage, the pollution of the reset spring 11 of the pressure reducing valve to high-purity gas can be avoided, the pressure reducing valve can be conveniently purged during use, and the cleaning treatment of the reset spring 11 with complex structure is also avoided.

The DOME pressure cavity 15 and the DOME pressure control port 16 can control output pressure through external loading pressure, so that the function of the pressure reducing valve is increased; the DOME pressure chamber 15 and the DOME pressure control port 16 can also be used as collecting chambers, so that the gas escaping after the fatigue fracture of the diaphragm can be effectively collected, and the escaping gas is led out to a safety zone. Is suitable for conveying dangerous gases with extremely toxicity, harm, flammability and explosiveness, and improves the safety.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A novel high clean gas relief valve, characterized in that includes:

the valve comprises a valve body (1), wherein the valve body (1) is provided with an air outlet cavity (1-5), an air inlet (1-1) and an air outlet (1-2), wherein the air inlet is communicated with the air outlet cavity (1-5), an inlet cavity (1-4) and a valve core cavity (1-3) are sequentially arranged between the air inlet (1-1) and the air outlet cavity (1-5), and a diaphragm sealing surface (1-6) is arranged at the top of the air outlet cavity (1-5);

the valve rod (3) is arranged in the air inlet cavity, and double lugs (3-3) of the valve rod (3) are clamped with double concave lug grooves (1-8) in the air inlet cavity;

the valve seat assembly (2) is screwed into the valve core cavity (1-3), the valve seat assembly (2) comprises a valve seat seal (2-2) and a valve seat screw (2-1), the valve seat seal (2-2) is sealed with the step end face of the valve core cavity (1-3), a taper hole of the valve seat seal (2-2) is attached to a taper head (3-1) of the valve rod (3), and a valve port (17) is formed between the taper hole and the taper head (3-1);

the diaphragm assembly (4) comprises a lifting screw (4-2), a corrugated stainless steel diaphragm (4-1) and a lifting nut (4-3) which are sequentially arranged from top to bottom, a diaphragm blocking sleeve (5) is sleeved on the lifting screw (4-2), the corrugated stainless steel diaphragm (4-1) covers a diaphragm sealing surface (1-6), and a screw hole of the lifting nut (4-3) is connected with a threaded rod (3-4) at the top of the valve rod (3);

the valve cover (6) is in butt joint connection with the air outlet cavity (1-5) of the valve body (1) through the screw cap (7), a reset spring (11) is arranged in the inner cavity of the valve cover (6), a flange edge cover of a cup opening of the diaphragm retaining sleeve (5) is arranged on the reset spring (11), and a limit nut (10) in the diaphragm retaining sleeve (5) is connected with the lifting screw (4-2);

the upper cover (8) is in threaded connection with the valve cover (6), an adjusting spring (13) is arranged in the diaphragm retaining sleeve (5), a spring cover (9) is arranged at the top of the adjusting spring (13), and an adjusting device (12) connected with the spring cover (9) is arranged at the top of the upper cover (8).

2. The novel high-purity gas pressure reducing valve according to claim 1, wherein: an annular guard edge (1-7) is arranged on the outer side of the diaphragm sealing surface (1-6).

3. The novel high-purity gas pressure reducing valve according to claim 2, wherein: sealing rings (14) are arranged at the joint of the upper cover (8) and the valve cover (6) and between the spring cover (9) and the upper cover (8).

4. A novel high clean gas pressure reducing valve according to claim 3, wherein: the inner cavities of the valve cover (6) and the upper cover (8) form a DOME pressure cavity (15), and a screw hole outlet connected with the DOME pressure cavity (15) is formed at the side surface of the upper cover (8) to form a DOME pressure control port (16).

5. The novel high-purity gas pressure reducing valve according to claim 4, wherein: the corrugated stainless steel diaphragm (4-1), the lifting screw (4-2) and the lifting nut (4-3) are welded into a whole, the lower part of the lifting screw (4-2) is a disc, the center of the upper part is a screw, the top of the screw is provided with a straight groove, and the center of the lifting nut (4-3) is provided with a straight threaded hole.

6. The novel high-purity gas pressure reducing valve according to claim 5, wherein: the diaphragm retaining sleeve (5) is cup-shaped, the cup opening is provided with a flange, and a through hole for the lifting screw (4-2) to pass through is formed in the center of the diaphragm retaining sleeve (5).

7. The novel high-purity gas pressure reducing valve according to claim 6, wherein: the valve gap (6) adopts the penetrating solid of revolution in center, and the upper end hole of valve gap (6) sets up the internal thread, and the internal thread outside sets up the seal groove, and the inside and outside of valve gap (6) lower extreme all is equipped with the flange limit, and the outer terminal surface of following of valve gap (6) lower extreme sets up the seal groove, is equipped with in the seal groove with nut (7) complex sealing washer (14).

8. The novel high-purity gas pressure reducing valve according to claim 7, wherein: the upper cover (8) is in an inverted cup shape, the opening of the lower part of the upper cover (8) is provided with a countersunk cavity, the outer edge of the lower part of the upper cover (8) is provided with threads and flange edges, a sealing groove is arranged between the threads and the flange edges, the upper bottom is thickened, the center of the upper cover is provided with an adjusting threaded hole, and the side surface of the countersunk cavity is provided with a threaded hole.

9. The novel high-purity gas pressure reducing valve according to claim 8, wherein: the adjusting device (12) comprises a knob and an adjusting screw rod, and the adjusting screw rod penetrates through the upper cover (8) to be connected with the spring cover (9).

10. The novel high-purity gas pressure reducing valve according to any one of claims 1 to 9, wherein: the spring cover (9) is disc-shaped with a boss in the center, and a sealing groove is formed in the outer edge of the spring cover (9).