Axial flow check valve

Abstract

The application relates to an axial flow type check valve, relates to the technical field of valves, and comprises a valve body, a valve seat, a valve clack and a guide rod, a flow guide sleeve is arranged in the valve body, a guide frame is arranged in the flow guide sleeve, a guide ring is arranged in the valve seat, the guide rod penetrates the guide ring and the guide frame in an axial direction respectively, the valve clack is axially sleeved on the guide rod, a reset spring is sleeved on the guide rod, the two ends of the reset spring abut against the guide frame and the valve clack respectively, the application further comprises an anti-impact assembly for protecting the valve clack, a slow-closing assembly for slowing down the closing speed of the valve clack, and an adjusting assembly for balancing the water pressure in the valve. Through cooperation of the anti-impact assembly, the slow-closing assembly and the adjusting assembly, the impact force generated when the check valve is just filled with water can be effectively resisted, meanwhile, the impact force formed when the valve clack is rapidly closed can be avoided, so that the service life of the check valve is prolonged.

Description

Technical Field

[0001] This application relates to the field of valve technology, and in particular to an axial flow check valve. Background Technology

[0002] An axial flow check valve is a protective device used to prevent backflow of media. It adopts an axial flow shuttle structure, and the valve disc is equipped with a buffer and shock-absorbing spring to avoid the impact vibration between the valve disc and the valve body when a conventional check valve is opened.

[0003] In related technologies, if the axial flow check valve opens / closes too quickly, the pressure inside the pipeline will suddenly increase. After the pressure inside the pipeline increases, the flow velocity of the medium inside the pipeline will increase. The high-speed flow of the medium can easily form water hammer at the bend of the pipeline, damaging the pipeline and affecting its service life. Summary of the Invention

[0004] In order to improve the service life of check valves, the purpose of this application is to provide an axial flow check valve.

[0005] The axial flow check valve provided in this application adopts the following technical solution:

[0006] An axial flow check valve includes a valve body, a valve seat, a valve disc, and a guide rod. A flow guide sleeve is disposed within the valve body, a guide frame is disposed within the flow guide sleeve, and a guide ring is disposed within the valve seat. The guide rod axially passes through both the guide ring and the guide frame. The valve disc is axially sleeved on the guide rod, and a return spring is sleeved on the guide rod. The two ends of the return spring abut against the guide frame and the valve disc, respectively.

[0007] The impact-resistant assembly includes a buffer rubber sheet disposed on the valve disc, with a guide rod axially penetrating the buffer rubber sheet, and an inert gas injected between the buffer rubber sheet and the valve disc;

[0008] The slow-closing assembly includes a telescopic outer rod rotatably connected to the valve seat, a sliding groove is provided inside the telescopic outer rod, a slow-closing spring is provided at the bottom of the sliding groove, a telescopic inner rod is provided on the slow-closing spring, and the telescopic inner rod is rotatably connected to the guide ring.

[0009] The regulating component is used to balance the water pressure inside the valve.

[0010] By adopting the above technical solution, the connection between the buffer rubber and the valve disc allows the buffer rubber to form a buffer airbag between the valve discs, thereby resisting the impact force generated by the check valve when water is first injected. This effectively reduces the impact force on the valve disc and thus improves the service life of the valve disc.

[0011] When the valve disc closes, the return spring deforms, releasing the stored kinetic energy to push the valve disc closer to the valve seat. This causes the guide ring to pull the slow-closing spring and stretch the slow-closing spring, thereby consuming part of the force of the return spring and reducing the speed of the valve disc when closing. This avoids the impact force caused by the rapid closing of the valve disc and can effectively improve the service life of the check valve.

[0012] Optionally, the impact-resistant assembly also includes a sliding ring axially sleeved on the guide rod, the sliding ring sliding along the surface of the guide rod, and the side of the sliding ring opposite to the guide rod being connected to the buffer rubber.

[0013] By adopting the above technical solution, when the buffer rubber is subjected to impact force, it slides on the surface of the guide rod, thereby consuming the kinetic energy of the impact force and increasing the service life of the valve disc.

[0014] Optionally, an anti-impact spring is axially fitted onto the guide rod, with one end of the anti-impact spring abutting against the sliding ring and the other end abutting against the valve disc.

[0015] By adopting the above technical solution, when the sliding ring is impacted and slides towards the valve disc, the sliding ring contacts the anti-impact spring, thereby reducing the sliding speed of the sliding ring and effectively preventing damage to the valve disc.

[0016] Optionally, a buffer groove is provided on the valve disc, an anti-impact spring extends into the buffer groove, and a sliding ring extends into the buffer groove and abuts against the side wall of the buffer groove.

[0017] By adopting the above technical solution, after the sliding ring extends into the buffer groove, the buffer rubber abuts against the valve disc, thereby increasing the pressure on the valve disc and causing the valve disc to slide.

[0018] Optionally, the guide rod has several adjustment holes between the sliding ring and the guide ring. The adjustment assembly includes a first adjustment airbag disposed inside the guide rod, and a first adjustment tube is disposed on the first adjustment airbag extending between the buffer rubber and the valve disc.

[0019] By adopting the above technical solution, external fluid can flow into the guide rod through the adjustment hole. At the same time, when the buffer rubber abuts against the valve disc, the first adjustment airbag is inflated, thereby increasing the volume of the first adjustment airbag to supplement the volume after the buffer rubber and valve disc are in contact.

[0020] Optionally, a first adjusting spring is provided inside the guide rod. One end of the first adjusting spring is connected to the side of the first adjusting airbag away from the adjusting hole, and the other end of the first adjusting spring is connected to the inner wall of the guide rod.

[0021] By adopting the above technical solution, when the first adjusting airbag is inflated, the first adjusting airbag squeezes the first adjusting spring and causes the first adjusting spring to deform and compress; when the first adjusting airbag is deflated, the first adjusting spring deforms and stretches to squeeze out the gas in the first adjusting airbag, thereby realizing the automatic inflation of the cushioning rubber.

[0022] Optionally, the end of the first adjusting airbag away from the first adjusting spring is provided with one end of the second adjusting spring, and the other end of the second adjusting spring is provided with the second adjusting airbag. The end of the second adjusting airbag away from the second adjusting spring is connected to the inner wall of the guide rod, and a second adjusting tube extending into the telescopic inner rod is provided on the second adjusting airbag.

[0023] By adopting the above technical solution, after the first regulating airbag is inflated, the second regulating airbag is compressed, so that the gas in the second regulating airbag flows into the telescopic inner rod through the second regulating tube, thereby driving the telescopic inner rod to retract.

[0024] Optionally, a rotating groove is provided on the guide ring, and a rotating shaft is provided on the inner wall of the rotating groove. The rotating shaft extends into the telescopic inner rod, and the second adjusting tube is provided inside the rotating shaft. Several elastic adjusting surfaces are provided on the surface of the telescopic inner rod.

[0025] By adopting the above technical solution, the telescopic inner rod can be injected with air while rotating. In addition, after the air is injected, the valve can be adjusted to protrude outward to balance the water pressure inside the valve.

[0026] Optionally, a piston is slidably connected inside the telescopic inner rod, and a rack is provided on the piston that extends into the telescopic outer rod. One end of the telescopic inner rod inside the telescopic outer rod is rotatably connected to a gear that meshes with the rack, and the inner wall of the telescopic outer rod is provided with a tooth groove that meshes with the gear.

[0027] By adopting the above technical solution, when the telescopic inner rod retracts, the gear rotates to drive the piston to retract, and at the same time, when the telescopic inner rod extends, the piston rod extends.

[0028] In summary, this application includes at least one of the following beneficial technical effects:

[0029] 1. This application uses a buffer rubber sheet to effectively resist the impact force generated by the check valve when water is first injected, effectively reducing the impact force on the valve disc and thus improving the service life of the valve disc;

[0030] 2. The slow-closing component of this application can effectively reduce the speed of the valve disc when closing, thereby avoiding the impact force formed by the rapid closing of the valve disc and improving the service life of the check valve. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of this application;

[0032] Figure 2 This is a structural schematic diagram of Embodiment 1 of this application, mainly showing the fixing rod;

[0033] Figure 3 This is a schematic diagram of the structure of Embodiment 2 of this application;

[0034] Figure 4 yes Figure 3 A magnified view of part A in the middle;

[0035] Figure 5 yes Figure 3 A magnified view of part B in the middle section;

[0036] Figure 6 yes Figure 3 A magnified view of part C in the middle.

[0037] Figure Descriptions: 1. Valve body; 2. Valve seat; 3. Guide ring; 4. Flow guide sleeve; 5. Guide rod; 6. Valve disc; 7. Anti-impact assembly; 701. Sliding ring; 702. Buffer rubber; 703. Anti-impact spring; 8. Slow-closing assembly; 801. Telescopic outer rod; 802. Slow-closing spring; 803. Telescopic inner rod; 804. Snap-fit ​​ring; 805. Ball bearing; 806. Snap-fit ​​spring; 807. Gear; 808. Rack; 809. Tooth groove; 810. Piston; 8 11. Elastic adjustment surface; 9. Adjustment component; 901. First adjustment airbag; 902. Second adjustment airbag; 903. First adjustment spring; 904. Second adjustment spring; 905. First adjustment tube; 906. Second adjustment tube; 10. Guide plug; 11. Fixing ring; 12. Positioning ring; 13. Fixing rod; 14. Return spring; 15. Buffer groove; 16. Sliding groove; 17. Fixing groove; 18. Rotating groove; 19. Rotating shaft; 20. Adjustment hole. Detailed Implementation

[0038] The following is in conjunction with the appendix Figure 1 - Appendix Figure 6 This application will be described in further detail below. Example 1:

[0039] An axial flow check valve, as described above Figure 1 , Figure 2 The valve body includes a valve body 1, a valve seat 2 is embedded at one end of the valve body 1, and the valve seat 2 is press-fitted with the inner wall of the valve body 1. A guide ring 3 is provided inside the valve seat 2, and two fixing rods 13 are fixedly connected to the guide ring 3, and the fixing rods 13 are fixedly connected to the valve seat 2.

[0040] Several first metal connecting pieces are fixedly connected inside the valve body 1. A flow guide sleeve 4 is fixedly connected to the end of the first metal connecting piece away from the inner wall of the valve body 1. A flow guide plug 10 is threadedly connected to the end of the flow guide sleeve 4 away from the positioning ring 12. The flow guide plug 10 has a through hole for the flow of fluid. In addition, several second connecting pieces are fixedly connected inside the flow guide sleeve 4. A fixing ring 11 is fixedly connected to the end of the second connecting piece away from the flow guide sleeve 4. A positioning ring 12 is axially inserted into the fixing ring 11 and fixed to the fixing screw.

[0041] A guide rod 5 is axially inserted through the guide ring 3 and the positioning ring 12. The guide rod 5 slides within the guide ring 3 and the positioning ring 12. An arc-shaped valve disc 6 is axially sleeved on the guide rod 5 and fixedly connected to its own surface. The valve disc 6 is located between the guide ring 3 and the positioning ring 12, and the side of the valve disc 6 facing the guide ring 3 protrudes arc-shaped.

[0042] A sealing ring is embedded at one end of the valve seat 2 near the positioning ring 12, and the arc-shaped edge of the valve disc 6 abuts against the valve seat 2 and the sealing ring. A return spring 14 is axially sleeved on the guide ring 3. One end of the return spring 14 is fixedly connected to the side of the valve disc 6 away from the guide ring 3, and the other end of the return spring 14 is fixedly connected to the positioning ring 12.

[0043] The implementation principle of Embodiment 1 of this application is as follows: After the valve body 1 is installed, the fluid flows into the valve body 1 from the guide ring 3. When the fluid accumulates to a certain level, it pushes the valve disc 6, causing the valve disc 6 to separate from the valve seat 2, thereby allowing the fluid to flow into the space of the valve body 1 where the guide sleeve 4 is located. As the fluid continues to flow, it pushes the valve disc 6 towards the guide sleeve 4, causing the valve disc 6 to come into contact with the guide sleeve 4. At the same time, the return spring 14 deforms and stretches. When the fluid stops flowing in, the return spring 14 deforms and stretches, thereby pushing the valve disc 6 towards the valve seat 2, causing the valve disc 6 to come into contact with the valve seat 2, thereby preventing the fluid in the valve seat 2 from flowing into the space of the valve body 1 where the guide sleeve 4 is located through the valve disc 6. Example 2:

[0044] An axial flow check valve, see Figure 3 The difference between this embodiment and Embodiment 1 is that it also includes an anti-impact component 7 for protecting the valve disc 6, a slow-closing component 8 for slowing down the closing speed of the valve disc 6, and an adjusting component 9 for balancing the water pressure inside the valve.

[0045] See Figure 3 , Figure 4The impact-resistant component 7 includes a sliding ring 701 slidably connected to the guide rod 5, and a sealing ring is embedded in the inner wall of the sliding ring 701, with the inner ring of the sealing ring abutting against the guide rod 5. In addition, an arc-shaped buffer rubber 702 is fixedly connected to the outer wall of the sliding ring 701, and the edge of the buffer rubber 702 is fixedly connected to the arc-shaped edge of the valve disc 6, so that a buffer cavity is formed between the buffer rubber 702 and the valve disc 6, and an inert gas is injected into the buffer cavity to form a buffer airbag.

[0046] See Figure 4 The valve disc 6 has an arc-shaped buffer groove 15 on the side facing the buffer rubber 702. One end of the anti-impact spring 703 is fixedly connected to the bottom of the buffer groove 15, and the other end of the anti-impact spring 703 is fixedly connected to the sliding ring 701. The anti-impact spring 703 is axially sleeved on the surface of the guide rod 5. The anti-impact spring 703 includes a dense part and a sparse part. When the buffer rubber 702 is impacted, the sliding ring 701 compresses the buffer spring, causing the sparse part of the buffer spring to contract rapidly in response to the external flow, while the dense part weakens the impact of the external flow and allows the sliding ring 701 to slowly insert into the buffer groove 15.

[0047] See Figure 3 , Figure 5 The slow-closing assembly 8 includes two telescopic outer rods 801 rotatably connected to the inner wall of the valve seat 2, wherein the telescopic outer rods 801 are test tube shaped. A sliding groove 16 is provided inside the telescopic outer rod 801, and the opening of the sliding groove 16 is positioned close to the guide rod 5. One end of the slow-closing spring 802 is fixedly connected to the bottom of the sliding groove 16, and the other end of the slow-closing spring 802 is fixedly connected to a test tube shaped telescopic inner rod 803. The open end of the telescopic inner rod 803 extends into the sliding groove 16 and slides along the opening direction of the sliding groove 16.

[0048] A snap ring 804 is fixedly connected to the telescopic outer rod 801, and the snap ring 804 is sleeved on the telescopic inner rod 803. Two snap grooves are opened on the snap ring 804, and a ball 805 is rolled in the snap groove. One end of a snap spring 806 is fixedly connected to the bottom of the snap groove, and the other end of the snap spring 806 abuts against the ball 805.

[0049] Two arc-shaped fixing grooves 17 are formed on the outer surface of the telescopic inner rod 803, corresponding to the positions of the ball bearings 805. The slope of the arc-shaped fixing grooves 17 away from the valve seat 2 is smaller than the slope of the fixing grooves 17 near the valve seat 2. When the telescopic inner rod 803 slides away from the telescopic outer rod 801, and the valve disc 6 abuts against the valve seat 2, the ball bearings 805 extend into the fixing grooves 17 and abut against them. Additionally, a sealing ring is provided on the snap ring 804 to abut against the surface of the telescopic inner rod 803.

[0050] See Figure 5 , Figure 6Two gears 807 are rotatably connected to the open end of the telescopic inner rod 803. The gears 807 abut against the telescopic outer rod 801. The inner wall of the telescopic outer rod 801 has two toothed grooves 809 corresponding to the positions of the gears 807, and the toothed grooves 809 mesh with the gears 807. At the same time, a piston 810 is slidably connected inside the telescopic inner rod 803. A rack 808 is fixedly connected to the piston 810 and meshes with the two gears 807 respectively. The rack 808 extends into the sliding groove 16 and the soft-closing spring 802.

[0051] The end of the telescopic inner rod 803 furthest from the telescopic outer rod 801 is rotatably connected to the guide ring 3, and the guide ring 3 is fixedly connected to the surface of the guide rod 5. Additionally, the guide ring 3 has two rotating grooves 18 corresponding to the positions of the telescopic inner rod 803. Rotating shafts 19 are fixedly connected to the two opposite side walls of each rotating groove 18. The rotating shafts 19 penetrate and extend into the telescopic inner rod 803, and a sealing ring is provided between the rotating shafts 19 and the telescopic inner rod 803 to prevent external fluids from entering the telescopic inner rod 803.

[0052] In addition, the side wall of the telescopic inner rod 803 is provided with a strip-shaped through hole, and the inner wall of the strip-shaped through hole is fixedly connected with an elastic adjustment surface 811, and the elastic adjustment surface 811 is located between the piston 810 and the guide ring 3.

[0053] See Figure 3 , Figure 4 , Figure 6 The guide rod 5 has several adjustment holes 20 in the portion between the sliding ring 701 and the guide ring 3, allowing external fluids to flow into the guide rod 5. The adjustment assembly 9 includes a connecting ring fixedly connected to the inner wall of the guide rod 5, and a first adjustment airbag 901 is embedded in the connecting ring, with the connecting ring located in the middle section of the first adjustment airbag 901.

[0054] The surface of the first adjusting airbag 901 is provided with compression pleats, and both ends of the first adjusting airbag 901 are fixedly connected to the first connecting plate. In addition, one end of the first adjusting spring 903 is fixedly connected to the first connecting plate at the end of the first adjusting airbag 901 away from the guide ring 3, and the other end of the first adjusting spring 903 is fixedly connected to the inner wall of the end of the guide rod 5 away from the adjusting hole 20.

[0055] See Figure 4 A first regulating tube 905 is fixedly connected to the first regulating airbag 901. The first regulating tube 905 is a soft rubber tube, and the first regulating tube 905 passes through the connecting ring, the outer wall of the guide rod 5, and the valve disc 6 in sequence, extending into the space between the buffer rubber 702 and the valve disc 6, so that the buffer airbag and the first regulating airbag 901 are connected.

[0056] See Figure 3 , Figure 4 , Figure 6The guide rod 5 is fixedly connected to a second adjusting airbag 902 at the end away from the first adjusting spring 903, and the surface of the second adjusting airbag 902 is provided with compression pleats. A second connecting plate is fixedly connected to the end of the second adjusting airbag 902 near the first adjusting airbag 901. One end of the second adjusting spring 904 is fixedly connected to the second connecting plate, and the other end of the second adjusting spring 904 is fixedly connected to the first connecting plate at the end of the first adjusting airbag 901 near the adjusting hole 20.

[0057] See Figure 6 A second adjusting tube 906 is fixedly connected to the second adjusting airbag 902, and the second adjusting tube 906 passes through the guide rod 5, the guide ring 3, and the rotating shaft 19 in sequence before extending into the telescopic inner rod 803, so that the second adjusting airbag 902 and the telescopic inner rod 803 are connected in the inner cavity of the piston 810 near the guide rod 5.

[0058] The implementation principle of Embodiment 2 of this application is as follows: After the check valve is installed, the fluid flows into the check valve from the valve seat 2 end. The initial flow of the fluid is fast and impacts the surface of the buffer rubber 702, pushing the buffer rubber 702 towards the valve disc 6. During this process, the buffer rubber 702, under the action of the anti-impact spring 703, first moves quickly towards the valve disc 6 to reduce the impact force of the fluid, and then slowly moves towards the valve disc 6. At the same time, the gas in the buffer airbag gradually flows into the first regulating airbag 901, causing the first regulating airbag 901 to expand to both sides of the connecting ring, thereby compensating for the volume inside the valve after the buffer airbag deflates.

[0059] Simultaneously, the first adjusting spring 903 and the second adjusting spring 904 deform and contract. The first adjusting spring 903 contacts the first adjusting airbag 901, and the second adjusting spring 904 contacts and compresses the second adjusting airbag 902. Part of the gas inside the second adjusting airbag 902 flows into the telescopic inner rod 803, causing the elastic adjusting surface 811 to expand outwards from the telescopic inner rod 803, thereby compensating for the volume loss of the second adjusting airbag 902.

[0060] In addition, as the fluid continuously impacts the buffer rubber 702 and abuts against the arc-shaped surface of the valve disc 6, pushing the valve disc 6 to slide towards the guide sleeve 4, during this process, the telescopic inner rod 803 moves towards the bottom of the sliding groove 16 under the action of the slow-closing spring 802, causing the gear 807 to rotate, thereby driving the piston 810 to slide towards the bottom of the sliding groove 16, thereby further extracting the gas in the second regulating airbag 902, and then pulling the first regulating airbag 901 to expand through the second regulating spring 904 to compensate for the volume of the buffer airbag after it has further deflated.

[0061] After the valve disc 6 comes into contact with the guide sleeve 4, the fluid flows over both sides of the valve disc 6, and at this time the fluid continuously squeezes the buffer rubber 702 and the valve disc 6, thereby stabilizing the overall structure. When the fluid stops flowing, the return spring 14 pushes the valve disc 6 toward the valve seat 2. At the same time, the slow-closing spring 802 pushes the telescopic inner rod 803 to slide away from the sliding groove 16, thereby causing the piston 810 to pump the gas in the telescopic inner rod 803 into the second regulating air bag 902.

[0062] After the second adjusting airbag 902 expands, it squeezes the first adjusting airbag 901 through the second adjusting spring 904. In addition, after the buffer rubber 702 is no longer impacted by the liquid, the first adjusting spring 903 can squeeze the first adjusting airbag 901 to compress the first adjusting airbag 901, thereby allowing the gas in the first adjusting airbag 901 to flow into the buffer airbag.

[0063] Furthermore, during the movement of valve disc 6, the deformation of the slow-closing spring 802 applies tension to the telescopic inner rod 803, thereby slowing down the closing speed of valve disc 6. Also, when valve disc 6 abuts against valve seat 2, the buffer airbag first abuts against valve seat 2 to prevent damage to valve disc 6 upon contact with valve seat 2. Once the gas in the part of the buffer airbag that abuts against valve seat 2 is released, valve disc 6 closes.

[0064] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be covered within the scope of protection of this application.

Claims

1. An axial flow check valve, comprising a valve body (1), a valve seat (2), a valve disc (6), and a guide rod (5), wherein a flow guide sleeve (4) is provided inside the valve body (1), a guide frame is provided inside the flow guide sleeve (4), and a guide ring (3) is provided inside the valve seat (2), the guide rod (5) axially penetrates the guide ring (3) and the guide frame respectively, the valve disc (6) is axially sleeved on the guide rod (5), and a return spring (14) is sleeved on the guide rod (5), the two ends of the return spring (14) abutting against the guide frame and the valve disc (6) respectively, characterized in that: Also includes The impact-resistant assembly (7) includes a buffer rubber (702) disposed on the valve disc (6), and the guide rod (5) axially penetrates the buffer rubber (702), and an inert gas is injected between the buffer rubber (702) and the valve disc (6); The slow-closing assembly (8) includes a telescopic outer rod (801) rotatably connected to the valve seat (2), a sliding groove (16) is provided in the telescopic outer rod (801), a slow-closing spring (802) is provided at the bottom of the sliding groove (16), a telescopic inner rod (803) is provided on the slow-closing spring (802), and the telescopic inner rod (803) is rotatably connected to the guide ring (3); Adjustment component (9), the adjustment component (9) is used to balance the water pressure inside the valve; The impact-resistant assembly (7) further includes a sliding ring (701) axially sleeved on the guide rod (5). The sliding ring (701) slides along the surface of the guide rod (5). The side of the sliding ring (701) away from the guide rod (5) is connected to the buffer rubber (702). The guide rod (5) is axially fitted with an anti-impact spring (703), one end of the anti-impact spring (703) abuts against the sliding ring (701), and the other end of the anti-impact spring (703) abuts against the valve disc (6); The valve disc (6) is provided with a buffer groove (15), the anti-impact spring (703) extends into the buffer groove (15), and the sliding ring (701) extends into the buffer groove (15) and abuts against the side wall of the buffer groove (15). The guide rod (5) has several adjustment holes (20) between the sliding ring (701) and the guide ring (3). The adjustment assembly (9) includes a first adjustment airbag (901) disposed in the guide rod (5). The first adjustment airbag (901) is provided with a first adjustment tube (905) extending between the buffer rubber (702) and the valve disc (6). The guide rod (5) is provided with a first adjusting spring (903). One end of the first adjusting spring (903) is connected to the side of the first adjusting airbag (901) away from the adjusting hole (20), and the other end of the first adjusting spring (903) is connected to the inner wall of the guide rod (5). The first adjusting airbag (901) has one end of the second adjusting spring (904) at the end away from the first adjusting spring (903), and the other end of the second adjusting spring (904) has the second adjusting airbag (902). The end of the second adjusting airbag (902) away from the second adjusting spring (904) is connected to the inner wall of the guide rod (5). The second adjusting airbag (902) has a second adjusting tube (906) that extends into the telescopic inner rod (803).

2. The axial flow check valve according to claim 1, characterized in that: The guide ring (3) is provided with a rotating groove (18), and a rotating shaft (19) is provided on the inner wall of the rotating groove (18). The rotating shaft (19) extends into the telescopic inner rod (803), and the second adjusting tube (906) is provided in the rotating shaft (19). The surface of the telescopic inner rod (803) is provided with a plurality of elastic adjusting surfaces (811).

3. An axial flow check valve according to claim 2, characterized in that: A piston (810) is slidably connected inside the telescopic inner rod (803). A rack (808) is provided on the piston (810) and extends into the telescopic outer rod (801). A gear (807) that meshes with the rack (808) is rotatably connected to one end of the telescopic inner rod (803) inside the telescopic outer rod (801). A tooth groove (809) that meshes with the gear (807) is provided on the inner wall of the telescopic outer rod (801).

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