Pressure reducing valve

Abstract

The pressure reducing valve comprises a valve body, a diaphragm and a valve element part, a medium inflow channel, a medium outflow channel, a valve element cavity, a valve seat cavity and an outlet cavity are formed in the valve body, a valve seat is fixedly installed in the valve seat cavity, an elastic pressing assembly used for pressing the diaphragm downwards to be attached to the valve seat is arranged at the upper end of the diaphragm, and a center channel is formed in the valve seat; the upper end of the valve element piece penetrates through a center channel of the valve seat and abuts against the diaphragm or is connected to the diaphragm, a small spring is arranged in the valve body, the middle of the diaphragm is provided with a flat portion, the elastic pressing assembly comprises a pressing plate abutting against the flat portion of the diaphragm and a first elastic piece acting on the pressing plate, and the lower end of the pressing plate is provided with a downward protruding portion protruding downwards. The lower convex part is provided with a middle flat surface and an arc-shaped surface arranged on the periphery of the middle flat surface, the radius of the arc-shaped surface of the lower convex part is R, the height of the flat part of the diaphragm and the valve seat is H when the diaphragm is not subjected to the acting force of the elastic pressing assembly, H / R is larger than or equal to 0.045 and smaller than or equal to 0.055, and therefore the service life of the diaphragm is effectively prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of valves, and in particular to a pressure reducing valve. Background Art

[0002] The pressure reducing valve is a pressure regulating device in an air path system, which includes a valve body, a diaphragm and a valve core member. The valve body is provided with a medium inlet channel, a medium outflow channel, a valve core chamber, a valve seat chamber and an outlet chamber. A valve seat is fixedly installed in the valve seat chamber, the diaphragm is arranged in the outlet chamber and the outer periphery of the diaphragm is pressed on the diaphragm sealing surface of the valve body, and a pressing assembly for pressing the diaphragm down to fit the valve seat is arranged at the upper end of the diaphragm. The valve seat is provided with a central channel, and a valve port is formed at the lower end of the central channel. The valve core member is axially slidably arranged in the valve core chamber, and the upper end of the valve core member passes through the central channel of the valve seat and is against or connected to the diaphragm. A small spring for pushing up the valve core member is arranged in the valve body. In the initial state, the force exerted by the pressing assembly on the diaphragm is greater than the force exerted by the valve core member on the diaphragm.

[0003] When the pressure reducing valve is working, the diaphragm is pressed onto the valve seat under the drive of the pressing assembly. After the fluid medium is introduced into the medium inflow channel, the fluid pressure acting on the lower end surface of the diaphragm will push the diaphragm upward until the pressure acting on the upper end surface of the diaphragm and the thrust acting on the lower end surface of the diaphragm reach a dynamic balance. When the valve port and the fluid pressure in the outlet cavity at the lower end of the diaphragm increase, the fluid thrust acting on the diaphragm is greater than the pressure acting on the upper end surface of the diaphragm, causing the diaphragm to move upward. At this time, the valve core moves upward under the action of the small spring, causing the valve port to decrease, increasing the throttling effect, and thereby reducing the output pressure, establishing a new dynamic balance, and until the valve port is closed.

[0004] In a pressure reducing valve, the diaphragm deforms significantly every time it is opened and closed, so the durability and service life of the diaphragm are technical issues that require special attention. Summary of the invention

[0005] The object of the present invention is to provide a pressure reducing valve, which can ensure that the stress between the diaphragm and the pressure plate is uniformized in the initial contact state and the final contact state by ensuring that the ratio of the height H of the flat part of the diaphragm to the valve seat and the radius R of the arc surface of the lower convex part of the diaphragm is between 0.045 and 0.055 when the diaphragm is not subjected to the force of the elastic pressing component, thereby preventing excessive stress from acting locally on the diaphragm, thereby effectively improving the service life of the diaphragm.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions: a pressure reducing valve, comprising a valve body, a diaphragm and a valve core member, wherein the valve body is provided with a medium inlet channel, a medium outlet channel, a valve core cavity, a valve seat cavity and an outlet cavity, a valve seat is fixedly installed in the valve seat cavity, the diaphragm is arranged in the outlet cavity and the outer periphery of the diaphragm is pressed on the diaphragm sealing surface of the valve body, an elastic pressing component for pressing the diaphragm down to fit the valve seat is arranged at the upper end of the diaphragm, the valve seat is provided with a central channel, a valve port is formed at the lower end of the central channel, the valve core member is axially slidably arranged in the valve core cavity, and the upper end of the valve core member passes through the valve The central channel of the seat is against or connected to the diaphragm, a small spring for pushing up the valve core member is arranged in the valve body, the middle of the diaphragm has a flat portion, the elastic pressing assembly includes a pressure plate against the flat portion of the diaphragm and a first elastic member acting on the pressure plate, the lower end of the pressure plate has a downwardly protruding lower convex portion, the lower convex portion has a middle flat surface and an arcuate surface arranged on the outer periphery of the middle flat surface, the radius of the arcuate surface of the lower convex portion is R, and the height between the flat portion of the diaphragm and the valve seat when the diaphragm is not subjected to the force of the elastic pressing assembly is H, wherein 0.045≤H / R≤0.055.

[0007] Furthermore, the flat portion of the diaphragm covers the lower convex portion of the pressing plate.

[0008] Furthermore, when the diaphragm is pressed against the upper end surface of the valve seat under the action of the elastic pressing assembly, the middle flat surface and the arc surface of the pressing plate both fit the upper end surface of the flat portion of the diaphragm.

[0009] Further, the middle flat surface of the pressure plate is within the upper end surface area of ​​the valve seat, the arcuate surface portion of the pressure plate is within the upper end surface area of ​​the valve seat, and the arcuate surface portion of the pressure plate is outside the upper end surface area of ​​the valve seat.

[0010] Further, 0.9 mm ≤ H ≤ 1.1 mm.

[0011] Furthermore, a pressure regulating assembly is provided on the valve body, and the pressure regulating assembly includes a pressure block and a connecting handle. The connecting handle is rotatably connected to the valve body, the pressure block is arranged at the lower end of the connecting handle and is located in the valve body, and the first elastic member is arranged between the pressure block and the pressure plate. The position of the pressure block is adjusted by the connecting handle to adjust the pressure of the elastic pressing assembly on the diaphragm.

[0012] Furthermore, a center positioning column is provided at the upper end of the diaphragm, an annular groove is provided on the periphery of the center positioning column, the first elastic member is partially accommodated in the annular groove, and the first elastic member is sleeved on the periphery of the center positioning column.

[0013] Furthermore, the valve body comprises a first valve body, a second valve body and a connecting sleeve for connecting the first valve body and the second valve body, and a diaphragm sealing surface is provided at the connecting end of the first valve body and the second valve body.

[0014] Furthermore, a limiting step is provided in the valve body, and the upper end surface of the outer circumference of the pressure plate cooperates with the limiting step to limit the maximum upward movement position of the pressure plate.

[0015] In summary, the present invention has the following beneficial effects: The pressure reducing valve of the present invention ensures that the stress between the diaphragm and the pressure plate is uniformized in the initial contact state and the final contact state by ensuring that the ratio of the height H between the flat portion of the diaphragm and the valve seat to the radius R of the arc surface of the lower convex portion of the diaphragm is between 0.045 and 0.055 when the diaphragm is not subjected to the force of the elastic pressing component, thereby preventing excessive stress from acting locally on the diaphragm and effectively improving the service life of the diaphragm. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0017] Figure 2 It is a schematic structural diagram of the diaphragm of the present invention when it is not pressed onto the valve seat by the pressing plate.

[0018] Figure 3 It is a structural schematic diagram of the diaphragm of the present invention when it is pressed onto the valve seat by the pressing plate.

[0019] Figure 4 It is a structural schematic diagram of a pressing plate of the present invention.

[0020] In the figure: 10, valve body; 11, medium inflow channel; 12, medium outflow channel; 13, valve core chamber; 14, valve seat chamber; 15, outlet chamber; 16, first valve body; 17, second valve body; 171, limit step; 18, connecting sleeve; 19, diaphragm sealing surface; 20, diaphragm; 21, flat portion; 30, valve core member; 40, valve seat; 41, valve plate; 50, elastic pressing assembly; 51, pressure plate; 511, lower convex portion; 512, flat surface; 513, arc surface; 52, first elastic member; 60, small spring; 70, pressure regulating assembly; 71, pressure block; 72, connecting handle. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings.

[0022] like Figure 1-Figure 4 As shown, a pressure reducing valve comprises a valve body 10, a diaphragm 20 and a valve core member 30. A medium inflow channel 11, a medium outflow channel 12, a valve core cavity 13, a valve seat cavity 14 and an outlet cavity 15 are arranged in the valve body 10. The outlet cavity 15 is directly connected with the medium outflow channel 12 on one hand, and is connected with the medium inflow channel 11 through the valve seat cavity 14 and the valve core cavity 13 on the other hand. After the medium enters from the medium inflow channel 11, it will pass through the valve core cavity 13, the valve seat cavity 14, the outlet cavity 15 and the medium outflow channel 12 in sequence.

[0023] A valve seat 40 is fixedly installed in the valve seat cavity 14, and the diameter of the valve core cavity 13 is smaller than the diameter of the valve seat cavity 14, so that a step surface is formed between the valve core cavity 13 and the valve seat cavity 14. A valve plate 41 cavity is arranged at the bottom of the valve seat 40, and a valve plate 41 is fixedly embedded in the valve plate 41 cavity. The valve seat 40 is provided with a central channel, and a valve port is formed at the lower end of the central channel. Specifically, a valve port is arranged in the middle of the valve plate 41, and the valve port is connected to the central channel. The valve core member 30 is axially slidably arranged in the valve core cavity 13, and the upper end of the valve core member 30 passes through the central channel of the valve seat 40 and abuts against or is connected to the diaphragm 20. A valve body 10 is provided with a valve for moving the valve core member 30 upward. The small spring 60 on the top, specifically, the valve core part 30 has an abutting portion, a sealing portion and a positioning portion, wherein the sealing portion is a sealing structure with a gradually narrowing outer opening, the valve core part 30 seals the valve port through the sealing portion, the abutting portion passes through the central channel and is abutted against the diaphragm 20 and connected to the diaphragm 20, the positioning portion is arranged in the valve core cavity 13, the small spring 60 is sleeved on the outer periphery of the positioning portion, an abutting surface is formed between the positioning portion and the sealing portion, the upper end of the small spring 60 is abutted against the abutting surface, and the other end of the small spring 60 abuts against the bottom of the valve core cavity 13, and the elastic reset force of the small spring 60 is used to ensure that the upper end surface of the valve core part 30 is always abutted against the diaphragm 20.

[0024] The diaphragm 20 is disposed in the outlet cavity 15 and the outer periphery of the diaphragm 20 is pressed onto the diaphragm sealing surface 19 of the valve body 10. The upper end of the diaphragm 20 is provided with an elastic pressing component 50 for pressing the diaphragm 20 down to fit the valve seat 40. The diaphragm 20 has a flat portion 21 in the middle, and the outer periphery of the flat portion 21 has an inner concave portion that is recessed downward. The elastic pressing assembly 50 includes a pressing plate 51 that is against the flat portion 21 of the diaphragm 20 and a first elastic member 52 that acts on the pressing plate 51. The first elastic member 52 is a large spring and the elastic force of the first elastic member 52 is greater than the elastic force of the small spring 60. The lower end of the pressing plate 51 has a downwardly protruding lower convex portion 511, and the lower convex portion 511 has a middle flat surface 512 and an arcuate surface 513 arranged on the outer periphery of the middle flat surface 512. The radius of the arcuate surface 513 of the lower convex portion 511 is R. When the diaphragm 20 is not subjected to the force of the elastic pressing assembly 50, the height between the flat portion 21 of the diaphragm 20 and the valve seat 40 is H, wherein 0.045≤H / R≤0.055. Specifically, the radius R of the arc surface 513 and the ratio of the height H of the flat portion 21 of the diaphragm 20 to the valve seat 40 when the diaphragm 20 is not subjected to the force of the elastic pressing assembly 50 will affect the initial contact area and the final contact area between the pressure plate 51 and the diaphragm 20. The different initial contact area and the final contact area will affect the different contact stresses, thereby affecting the durability and service life of the diaphragm 20.

[0025] In the initial state, the pressure on the upper end surface of the diaphragm 20 is greater than the supporting force on the lower end surface of the diaphragm 20. At this time, the diaphragm 20 will be pressed against the upper end surface of the valve seat 40 by the pressure plate 51. In this state, the pressure plate 51 and the diaphragm 20 are in initial contact area, and the flat portion 21 of the diaphragm 20 abuts against the middle flat surface 512 of the pressure plate 51 and most or all of the arc surface 513. The valve core member 30 will move downward under the action of the diaphragm 20 and open the valve port. After the fluid medium is introduced into the medium inflow channel 11, the fluid pressure acting on the lower end surface of the diaphragm 20 will push the diaphragm 20 to move upward until the pressure acting on the upper end surface of the diaphragm 20 and the thrust acting on the lower end surface of the diaphragm 20 reach a dynamic balance. In this state, the pressure plate 51 and the diaphragm 20 are in final contact area, and the flat portion 21 of the diaphragm 20 only abuts against the middle flat surface 512 of the pressure plate 51.

[0026] In some embodiments, the flat portion 21 of the diaphragm 20 covers the lower convex portion 511 of the pressing plate 51. That is, the lower convex portion 511 of the pressing plate 51 is within the area where the flat portion 21 of the diaphragm 20 is located.

[0027] In some embodiments, when the diaphragm 20 is pressed against the upper end surface of the valve seat 40 by the elastic pressing assembly 50 , the middle flat surface 512 and the arc surface 513 of the pressing plate 51 both fit the upper end surface of the flat portion 21 of the diaphragm 20 .

[0028] In some embodiments, the middle flat surface 512 of the pressure plate 51 is within the upper end surface area of ​​the valve seat 40, the arcuate surface 513 of the pressure plate 51 is partially within the upper end surface area of ​​the valve seat 40, and the arcuate surface 513 of the pressure plate 51 is partially outside the upper end surface area of ​​the valve seat 40.

[0029] Furthermore, 0.9 mm ≤ H ≤ 1.1 mm. The height H between the flat portion 21 of the diaphragm 20 and the valve seat 40 when the diaphragm 20 is not subjected to the force of the elastic pressing assembly 50 is determined by the flow coefficient of each valve. If H is too large, it is not conducive to the miniaturization design of the pressure reducing valve. If H is too small, the discharge flow is too small.

[0030] In some embodiments, a pressure regulating assembly 70 is provided on the valve body 10, and the pressure regulating assembly 70 includes a pressing block 71 and a connecting handle 72, and the connecting handle 72 is rotatably connected to the valve body 10, and the pressing block 71 is provided at the lower end of the connecting handle 72 and is located in the valve body 10, and the first elastic member 52 is provided between the pressing block 71 and the pressure plate 51, and the position of the pressing block 71 is adjusted by the connecting handle 72 to adjust the pressure of the elastic pressing assembly 50 on the diaphragm 20. Specifically, the connecting handle 72 has a screwing portion, and the screwing portion facilitates the user to screw the connecting handle 72.

[0031] In some embodiments, the upper end of the diaphragm 20 is provided with a central positioning column, and the diaphragm 20 is provided with an annular groove on the periphery of the central positioning column, and the first elastic member 52 is partially accommodated in the annular groove, and the first elastic member 52 is sleeved on the periphery of the central positioning column. Through this arrangement, the first elastic member 52 is prevented from being offset during the expansion and contraction process, thereby improving its stability.

[0032] In some embodiments, the valve body 10 includes a first valve body 16, a second valve body 17, and a connecting sleeve 18 for connecting the first valve body 16 and the second valve body 17, and a diaphragm sealing surface 19 is provided at the connecting end of the first valve body 16 and the second valve body 17. Specifically, the first valve body 16 is provided with a positioning groove with an upper end opening, the second valve body 17 is arranged in the positioning groove, the lower end of the second valve body 17 is provided with a flange, the upper end of the inner ring of the connecting sleeve 18 is provided with a conical crimping surface, and the lower end of the inner ring is provided with a threaded connection portion, the connecting sleeve 18 is connected to the first valve body 16 through the threaded connection portion, and the second valve body 17 is firmly crimped onto the first valve body 16 through the crimping fit between the conical crimping surface and the flange.

[0033] In some embodiments, a limiting step 171 is provided in the valve body 10 , and the upper end surface of the outer circumference of the pressure plate 51 cooperates with the limiting step 171 to limit the highest upward position of the pressure plate 51 .

[0034] In summary, the present invention has the following beneficial effects: The pressure reducing valve of the present invention ensures that the stress between the diaphragm 20 and the pressure plate 51 is uniformed in the initial contact state and the final contact state by making the ratio of the height H between the flat portion 21 of the diaphragm 20 and the valve seat 40 and the radius R of the arc surface 513 of the lower convex portion 511 of the diaphragm 20 be between 0.045 and 0.055 when the diaphragm 20 is not subjected to the force of the elastic pressing assembly 50, thereby preventing excessive stress from acting locally on the diaphragm 20, thereby effectively improving the service life of the diaphragm 20.

[0035] When the height H is 0.9 mm, the experimental data of the maximum stress value and service life of the diaphragm under different radii are as follows: When the height H is 1.026mm, the experimental data of the maximum stress value and service life of the diaphragm under different radii are as follows: When the height H is 1.1 mm, the experimental data of the maximum stress value and service life of the diaphragm under different radii are as follows: The above description is only a preferred embodiment of the present invention, so all equivalent changes or modifications made according to the structure, characteristics and principles described in the scope of the patent application of the present invention are included in the scope of the patent application of the present invention.

Claims

1. A pressure reducing valve, characterized in that: The invention comprises a valve body (10), a diaphragm (20) and a valve core member (30), wherein the valve body (10) is provided with a medium inflow channel (11), a medium outflow channel (12), a valve core chamber (13), a valve seat chamber (14) and an outlet chamber (15), wherein a valve seat (40) is fixedly installed in the valve seat chamber (14), the diaphragm (20) is arranged in the outlet chamber (15) and the outer periphery of the diaphragm (20) is pressed on the diaphragm sealing surface (19) of the valve body (10), the upper end of the diaphragm (20) is provided with an elastic pressing component (50) for pressing the diaphragm (20) down to fit the valve seat (40), the valve seat (40) is provided with a central channel, the lower end of the central channel is formed with a valve port, the valve core member (30) is axially slidably arranged in the valve core chamber (13), the upper end of the valve core member (30) passes through the central channel of the valve seat (40) and abuts against or is connected to the diaphragm (20). The diaphragm (20) is provided with a small spring (60) for pushing up the valve core member (30), the diaphragm (20) has a flat portion (21) in the middle, the elastic pressing assembly (50) comprises a pressing plate (51) against the flat portion (21) of the diaphragm (20) and a first elastic member (52) acting on the pressing plate (51), the lower end of the pressing plate (51) has a downwardly protruding portion (511), The lower convex portion (511) has a middle flat surface (512) and an arcuate surface (513) arranged on the outer periphery of the middle flat surface (512), the radius of the arcuate surface (513) of the lower convex portion (511) is R, and the height between the flat portion (21) of the diaphragm (20) and the valve seat (40) when the diaphragm (20) is not subjected to the force of the elastic pressing component (50) is H, wherein 0.045≤H / R≤0.

055.

2. A pressure reducing valve according to claim 1, characterized in that: The flat portion (21) of the diaphragm (20) covers the lower convex portion (511) of the pressure plate (51).

3. A pressure reducing valve according to claim 1, characterized in that: When the diaphragm (20) is pressed against the upper end surface of the valve seat (40) under the action of the elastic pressing assembly (50), the middle flat surface (512) and the arc surface (513) of the pressing plate (51) both fit the upper end surface of the flat portion (21) of the diaphragm (20).

4. A pressure reducing valve according to claim 1, characterized in that: The middle flat surface (512) of the pressure plate (51) is within the upper end surface area of ​​the valve seat (40), the arcuate surface (513) of the pressure plate (51) is partially within the upper end surface area of ​​the valve seat (40), and at the same time, the arcuate surface (513) of the pressure plate (51) is partially outside the upper end surface area of ​​the valve seat (40).

5. A pressure reducing valve according to any one of claims 1 to 4, characterized in that: Among them, 0.9mm≤H≤1.1mm.

6. A pressure reducing valve according to claim 5, characterized in that: The valve body (10) is provided with a pressure regulating assembly (70), and the pressure regulating assembly (70) includes a pressure block (71) and a connecting handle (72). The connecting handle (72) is rotatably connected to the valve body (10), the pressure block (71) is arranged at the lower end of the connecting handle (72) and is located in the valve body (10), and the first elastic member (52) is arranged between the pressure block (71) and the pressure plate (51). The position of the pressure block (71) is adjusted by the connecting handle (72) to adjust the pressure of the elastic pressing assembly (50) on the diaphragm (20).

7. A pressure reducing valve according to claim 5, characterized in that: The upper end of the diaphragm (20) is provided with a central positioning column, and the diaphragm (20) is provided with an annular groove on the outer periphery of the central positioning column, and the first elastic member (52) is partially accommodated in the annular groove, and the first elastic member (52) is sleeved on the outer periphery of the central positioning column.

8. A pressure reducing valve according to claim 5, characterized in that: The valve body (10) comprises a first valve body (16), a second valve body (17) and a connecting sleeve (18) for connecting the first valve body (16) and the second valve body (17); a diaphragm sealing surface (19) is provided at the connecting end of the first valve body (16) and the second valve body (17).

9. A pressure reducing valve according to claim 5, characterized in that: A limiting step (171) is provided in the valve body (10), and the upper end surface of the outer circumference of the pressure plate (51) cooperates with the limiting step (171) to limit the highest upward position of the pressure plate (51).

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