One-way valve

Abstract

The utility model provides a one-way valve which comprises a valve seat portion and a piston, and one end of the valve seat portion is provided with a valve port. The piston is movably arranged in the valve seat part to open and close the valve port, the piston comprises a piston body and a guide structure, the piston body is of a shell-shaped structure, the guide structure is connected with the periphery of the piston body, and the guide structure is in sliding fit with the valve seat part. According to the scheme, the piston is movably arranged in the valve pipe, and when the pressure of the side, close to the valve port, of the piston is smaller than that of the side, away from the valve port, of the piston, the piston blocks the valve port; when the pressure of one side of the piston close to the valve port is larger than that of one side of the piston away from the valve port, the piston leaves the valve port, and the valve port is opened. The piston body is of the shell-shaped structure, so that the mass of the piston is small, when the pressure difference between the two sides of the piston changes, the influence of the self weight on the piston is smaller, and the piston can move more flexibly and rapidly to open or close the valve port. According to the scheme, the pressure difference for driving the piston is smaller, and the movement of the piston is more flexible.

Description

Technical Field

[0001] The utility model relates to the technical field of check valves, and more specifically, to a check valve. Background Art

[0002] In some check valves, a piston is used to block or open the check valve. The pressure difference on both sides of the piston causes the piston to block or open the valve port of the check valve, so as to achieve the purpose of automatically unidirectional flow of the fluid in the check valve.

[0003] However, the piston of the check valve in the prior art has a large weight, so that the valve port of the check valve is greatly affected by the self-weight of the piston during the opening and closing processes, and the pressure difference required to block or open the valve port is too large, resulting in inflexible movement of the piston and inability to be applicable to more working environments. Therefore, it is necessary to reduce the weight of the piston and provide a check valve with a smaller pressure difference for driving the piston. Summary of the Utility Model

[0004] The utility model provides a check valve to solve the problem of inflexible movement of the piston of the check valve in the prior art.

[0005] To solve the above problems, the utility model provides a check valve, which includes a valve seat part and a piston. One end of the valve seat part has a valve port; the piston is movably arranged in the valve seat part to open and close the valve port. The piston includes a piston body and a guiding structure. The piston body is a shell-like structure, and the guiding structure is connected to the outer periphery of the piston body and is in sliding fit with the valve seat part.

[0006] Further, the piston body includes a flow-through section, a blocking section and a guiding section connected in sequence. The outer diameter of the flow-through section is less than or equal to the inner diameter of the valve port, the outer diameter of the blocking section is greater than the inner diameter of the valve port, the outer diameter of the guiding section is less than the outer diameter of the blocking section, the guiding section is arranged on the side of the blocking section away from the valve port, and the blocking section is used to block the valve port.

[0007] Further, the cross-section of the piston along the axial direction of the check valve is a piston cross-section. The angle between the two sides of the flow-through section in the piston cross-section is a flow-through angle, and the range of the flow-through angle is 50° to 100°.

[0008] Further, the thickness range of the shell wall of the piston body is 0.3 mm to 1.5 mm.

[0009] Further, the material of the piston is stainless steel.

[0010] Further, the valve seat part includes a valve pipe and a valve seat. The outer ring of the valve seat is connected to the inner wall of the valve pipe. The valve seat has a valve port. The piston is movably arranged in the valve pipe to open and close the valve port. The check valve further includes a retaining ring, which is arranged on the side of the piston away from the valve port. The valve pipe, the valve seat and the retaining ring are made of cast iron or steel.

[0011] Further, the guiding structure includes a plurality of sheet-like structures which are distributed along the outer periphery of the piston body and fixed to the piston body. The outer side wall of the sheet-like structure is in sliding fit with the valve seat portion. Along the axial direction of the one-way valve, the length of the piston is N, and the distance between the end of the sheet-like structure away from the valve port and the end of the piston body away from the valve port is M. The ratio range of M to N is 0.35 to 0.7.

[0012] Further, the one-way valve further includes a retaining ring which is arranged on the side of the piston facing away from the valve port and fixed in the valve seat portion. The retaining ring is used to stop the piston. The retaining ring includes a first annular section, and the inner diameter of the first annular section is smaller than the outer diameter of the piston. The end face of the first annular section close to the valve port is in stop fit with the end face of the piston facing away from the valve port.

[0013] Further, the retaining ring further includes a second annular section which is connected to the end face of the first annular section close to the valve port. The inner diameter of the second annular section is larger than that of the first annular section. The guiding structure includes a plurality of sheet-like structures, and the end of the sheet-like structure facing away from the valve port has a retracted section which can be inserted into the inner ring of the second annular section.

[0014] Further, the outer sides of the retracted sections of the plurality of sheet-like structures are located on the same annular circle. The diameter of the annular circle is E, and the inner diameter of the second annular section is F. F is larger than E, and the difference range between E and F is 0.3 mm to 1.5 mm.

[0015] Further, the piston is processed by powder metallurgy; or, the piston is processed by die forming.

[0016] Applying the technical solution of the present utility model, a one-way valve is provided, which includes a valve seat portion and a piston. One end of the valve seat portion has a valve port; the piston is movably arranged in the valve seat portion to open and close the valve port. The piston includes a piston body and a guiding structure. The piston body is a shell-like structure. The guiding structure is connected to the outer periphery of the piston body and is in sliding fit with the valve seat portion. With this solution, the piston is movably arranged in the valve tube. When the pressure on the side of the piston close to the valve port is less than the pressure on the side of the piston away from the valve port, the piston blocks the valve port; when the pressure on the side of the piston close to the valve port is greater than the pressure on the side of the piston away from the valve port, the piston leaves the valve port and the valve port opens. The piston body being a shell-like structure makes the mass of the piston smaller. When the pressure difference between the two sides of the piston changes, the piston is less affected by its own weight and can move more flexibly and quickly to open or close the valve port. Through this solution, the pressure difference for driving the piston is smaller, making the movement of the piston more flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings forming a part of this application are used to provide a further understanding of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation of the present utility model. In the drawings:

[0018] Figure 1 shows a schematic structural view of a check valve provided by an embodiment of the present utility model;

[0019] Figure 2 shows Figure 1 a schematic structural view of the piston of the check valve in

[0020] Figure 3 shows Figure 2 a cross-sectional view taken along line A-A in

[0021] Figure 4 shows Figure 1 a schematic structural view of the piston of the check valve in

[0022] Figure 5 shows Figure 4 a cross-sectional view taken along line B-B in

[0023] Figure 6 shows Figure 1 a schematic structural view of the retaining ring of the check valve in

[0024] Figure 7 shows Figure 1 a schematic structural view of the check valve when the valve port is closed in

[0025] Figure 8 shows Figure 7 a partial enlarged view at C in

[0026] Figure 9 shows Figure 7 a partial enlarged view at D in

[0027] Among them, the above-mentioned drawings include the following reference numerals:

[0028] 10, valve tube;

[0029] 11, first connection section;

[0030] 12, second connection section; 121, first positioning surface; 122, second positioning surface;

[0031] 13, third connection section;

[0032] 20, valve seat;

[0033] 21, valve port; 22, first annular flow guiding surface; 221, first included angle; 23, second annular flow guiding surface; 231, second included angle;

[0034] 30. Piston

[0035] 31. Piston body; 311. Flow-through section; 312. Sealing section; 313. Flow-guiding section

[0036] 32. Guiding structure; 321. Flaky structure

[0037] 3211. First section; 3212. Second section; 3213. Retracted section; 3214. Flow-guiding inclined surface

[0038] 33. Flow-through angle

[0039] 34. First flow-guiding fillet

[0040] 35. Second flow-guiding fillet

[0041] 36. Arc surface

[0042] 40. Retaining ring; 41. First annular section; 42. Second annular section; 43. First annular inclined surface; 44. Second annular inclined surface Detailed implementation mode

[0043] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and in no way restricts the present utility model and its application or use. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

[0044] As Figures 1 to 9 shown, an embodiment of the present utility model provides a one-way valve, including a valve seat portion and a piston 30. One end of the valve seat portion has a valve port 21; the piston 30 is movably arranged in the valve seat portion to open and close the valve port 21. The piston 30 includes a piston body 31 and a guiding structure 32. The piston body 31 is a shell-like structure. The guiding structure 32 is connected to the outer periphery of the piston body 31, and the guiding structure 32 is in sliding fit with the valve seat portion.

[0045] With this solution, the piston 30 is movably arranged in the valve tube 10. When the pressure on the side of the piston 30 close to the valve port 21 is less than the pressure on the other side of the piston 30, the piston 30 blocks the valve port 21; when the pressure on the side of the piston 30 close to the valve port 21 is greater than the pressure on the side of the piston 30 away from the valve port 21, the piston 30 moves away from the valve port 21 and the valve port 21 opens. The body of the piston 30 is of a shell-like structure, making the mass of the piston 30 smaller. When the pressure difference between the two sides of the piston 30 changes, the piston 30 is less affected by its own weight and can move more flexibly and quickly to open or close the valve port 21. Through this solution, the pressure difference driving the piston 30 is smaller, making the movement of the piston 30 more flexible.

[0046] Optionally, the piston body 31 is of a shell-like structure, and the shell-like structure has an open cavity, and the opening of the cavity is arranged at one end of the piston body 31 away from the valve port 21. The method of arranging a weight-reducing cavity in the piston 30 can also be adopted to reduce the influence of the piston self-weight on the flexibility of the one-way valve.

[0047] As Figure 4 shown, the piston body 31 includes a flow-through section 311, a blocking section 312 and a diversion section 313 connected in sequence. The outer diameter of the flow-through section 311 is less than or equal to the inner diameter of the valve port 21, the outer diameter of the blocking section 312 is greater than the inner diameter of the valve port 21, the outer diameter of the diversion section 313 is less than the outer diameter of the blocking section 312, the diversion section 313 is arranged on the side of the blocking section 312 away from the valve port 21, and the blocking section 312 is used to block the valve port 21.

[0048] It can be understood that when the piston 30 blocks the valve port 21, the flow-through section 311 of the piston body 31 is inserted into the valve port 21 to block the valve port. The outer diameter of the blocking section 312 is greater than the inner diameter of the valve port 21, which can ensure sealing of the valve port 21. When the piston 30 opens the valve port 21, the medium flows through the gap between the flow-through section 311 and the valve port 21, and the medium flows along the outer side walls of the flow-through section 311, the blocking section 312 and the diversion section 313 in sequence.

[0049] As Figure 4 shown, one end of the flow-through section 311 connected to the blocking section 312 is the first end, the other end of the flow-through section 311 is the second end, the flow-through section 311 is a tapered section, the outer diameter of the first end is greater than the outer diameter of the second end, and the position where the first end is connected to the blocking section 312 has a first diversion fillet 34, and the second end has a second diversion fillet 35; one end of the diversion section 313 connected to the blocking section 312 is the third end, the other end of the diversion section 313 is the fourth end, the diversion section 313 is a tapered section, and the outer diameter of the third end is greater than the outer diameter of the fourth end.

[0050] With this setting, the flow passage 311 is a tapered section, which guides the medium and buffers the movement of the medium, so that the medium will not cause too much impact on the piston body 31, and increases the flow capacity of the medium. The diversion section 313 is a tapered section, and the outer diameter of the third end is larger than that of the fourth end, so that the flow area for the medium to flow along the outer side wall of the diversion section 313 gradually increases, enhancing the flow capacity of the check valve without increasing the inner diameter of the valve seat portion.

[0051] Optionally, the outer wall of the flow passage 311 can be selected as an arc surface, so that the medium flows along the arc surface to buffer the impact of the medium; the outer wall of the diversion section 313 can be selected as an arc surface, so that the medium flows along the arc surface to buffer the impact of the medium.

[0052] As Figure 5 shown, the cross-section of the piston 30 along the axial direction of the check valve is the piston cross-section, and the angle between the two sides of the flow passage 311 in the piston cross-section is the flow angle 33, and the range of the flow angle 33 is 50° to 100°.

[0053] When the piston 30 is separated from the valve port 21, the medium flows through the gap between the flow passage 311 and the valve port 21, and the medium flows along the outer side wall of the flow passage 311 to buffer the impact of the medium. When the range of the flow angle 33 is 50° to 100°, the buffering effect on the medium is better and the medium can flow better.

[0054] In a specific embodiment of the present invention, the thickness range of the shell wall of the piston body 31 is 0.3 mm to 1.5 mm. Within this thickness range, the weight of the piston body 31 can be reduced while ensuring the stiffness of the piston body 31, reducing the influence of the self-weight of the piston 30 on the opening and closing of the check valve, and making the movement of the piston 30 in the valve seat portion more flexible.

[0055] As Figure 3 shown, the guiding structure 32 includes a plurality of sheet-like structures 321, and the plurality of sheet-like structures 321 are distributed along the outer circumference of the piston body 31. One end of the piston body 31 facing the valve port 21 opens or blocks the valve port 21. Along the radial direction of the check valve, the side of the sheet-like structure 321 facing away from the piston body 31 is slidably matched with the valve seat portion.

[0056] The medium flows through the gap between the valve port and the piston body 31, and passes through the space between two adjacent sheet-like structures 321 to flow to the side of the piston 30 facing away from the valve port 21. The plurality of sheet-like structures 321 are distributed along the circumferential direction of the piston body 31, so that the guiding effect of the valve seat portion on the piston 30 is more uniform, and the piston 30 moves along the axial direction of the valve seat portion without being skewed and getting stuck.

[0057] As Figure 1 、 Figure 3 AndFigure 4 As shown, the guiding structure 32 includes a plurality of sheet-like structures 321. The one-way valve further includes a retaining ring 40 which is arranged on the side of the piston 30 facing away from the valve port 21 and is fixed within the valve seat portion. The sheet-like structure 321 includes a first section 3211 and a second section 3212 which are connected to each other. The first section 3211 is connected to the piston body 31. One end of the first section 3211 close to the valve port 21 has a flow guiding inclined surface 3214. The connecting surface between the first section 3211 and the second section 3212 is flush with the end surface of the piston body 31 facing away from the valve port 21. The second section 3212 is arranged on the side of the first section 3211 away from the piston 30 along the axial direction of the one-way valve, and the second section 3212 is in a retaining fit with the retaining ring 40.

[0058] The retaining ring 40 is arranged on the side of the piston 30 facing away from the valve port 21 to stop the piston 30 and prevent the piston 30 from disengaging from the valve seat portion, limiting the piston between the retaining ring 40 and the valve port 21, so as to realize that the piston 30 is driven by the pressure difference on both sides to automatically open and close the valve port 21. The first section 3211 of the sheet-like structure 321 is connected to the piston body 31. Preferably, the first section 3211 should be connected to the flow passage section 311 of the piston body 31 to avoid interference between the first section 3211 and the valve seat portion when the piston 30 closes the valve port 21.

[0059] The flow guiding inclined surface 3214 guides the medium to buffer the impact of the medium on the sheet-like structure 321, avoiding deformation or damage of the sheet-like structure 321 under the impact of the medium and prolonging the service life of the sheet-like structure 321.

[0060] As Figure 3 shown, the length of the second section 3212 along the axial direction of the one-way valve is M, and the length of the piston 30 along the axial direction of the one-way valve is N. The ratio range of M to N is 0.35 to 0.7. With such a setting, the sheet-like structure 321 can reduce the weight of the piston 30 as much as possible while ensuring the guiding function.

[0061] Optionally, the length M of the second section 3212 along the axial direction of the one-way valve is greater than or equal to 1 mm to ensure sufficient guiding length.

[0062] Furthermore, in a specific embodiment of the present utility model, the piston 30 is processed by powder metallurgy; or, the piston 30 is processed by die forming.

[0063] Processing the piston 30 by powder metallurgy has fewer processes, high material utilization rate, can save costs, and can adapt to the complex shape of the piston 30.

[0064] Adopting die forming to process the piston 30 has higher production efficiency, higher manufacturing precision of the produced piston 30, and can form the piston 30 with a complex structure at one time without multiple processing.

[0065] like Figure 6 As shown, the one-way valve also includes a retaining ring 40, which is arranged on the side of the piston 30 away from the valve port 21. The retaining ring 40 is fixed in the valve seat portion. The retaining ring 40 is used to stop the piston 30. The retaining ring 40 includes a first annular segment 41. The inner diameter of the first annular segment 41 is smaller than the outer diameter of the piston 30. The end face of the first annular segment 41 close to the valve port 21 cooperates with the end face stop of the piston 30 away from the valve port 21.

[0066] The inner diameter of the first annular segment 41 is smaller than the outer diameter of the piston 30 , so that the end surface of the first annular segment 41 close to the valve port 21 stops the piston 30 and prevents the piston 30 from falling out of the valve seat.

[0067] like Figure 6 As shown, the retaining ring 40 also includes a second annular segment 42, which is connected to the end face of the first annular segment 41 near the valve port 21. The inner diameter of the second annular segment 42 is larger than the inner diameter of the first annular segment 41. The guide structure 32 includes a plurality of sheet structures 321. The sheet structure 321 has a retracted section 3213 at one end facing away from the valve port 21. The retracted section 3213 can be inserted into the inner ring of the second annular segment 42.

[0068] Optionally, the second annular segment 42 is clearance-fitted with the retracted segment 3213 , so that the movement of the piston 30 is more flexible, thereby preventing the second annular segment 42 from getting stuck on the piston 30 .

[0069] like Figure 4 and Figure 6 As shown, the outer sides of the retracted sections 3213 of the multiple sheet structures 321 are located in the same annular ring, the diameter of the annular ring is E, the inner diameter of the second annular section 42 is F, F is greater than E, and the difference between E and F ranges from 0.3mm to 1.5mm.

[0070] By setting F greater than E, a clearance fit is achieved between the second annular segment 42 and the retracted segment 3213 , the second annular segment 42 radially limits the retracted segment 3213 , and prevents the second annular segment 42 and the retracted segment 3213 from getting stuck and affecting the normal operation of the piston 30 .

[0071] like Figure 6 As shown, the inner ring of the first ring segment 41 has a first ring bevel 43 , and the inner ring of the second ring segment 42 has a second ring bevel 44 . The first ring bevel 43 and the second ring bevel 44 are used to guide the medium.

[0072] The medium flows through the valve port 21 towards the retaining ring 40. The impact of the medium on the retaining ring 40 is relatively large. The first annular inclined surface 43 and the second annular inclined surface 44 conduct the medium, which can buffer the impact of the medium, make the flow of the medium more stable, increase the flow capacity of the retaining ring 40, and thus improve the flow efficiency of the one-way valve.

[0073] Furthermore, in a specific embodiment of the present utility model, the first annular inclined surface 43 and the second annular inclined surface 44 are located on the same conical surface, making the flow of the medium smoother, increasing the flow capacity at the retaining ring 40, and maximizing the flow rate in the smallest space.

[0074] The first annular inclined surface 43 and the second annular inclined surface 44 make the flow area of the medium change gradually without sudden change, reducing the impact of the area change on the flow of the medium and avoiding the medium turbulence caused by the sudden change of the area.

[0075] Furthermore, the second annular inclined surface 44 plays a guiding role in the stop fit between the piston 30 and the retaining ring 40, enabling the retracted section 3213 of the piston 30 to cooperate more smoothly with the second annular section 42.

[0076] As Figure 6 shown, the inner diameter of the end of the first annular inclined surface 43 close to the valve port 21 is smaller than the inner diameter of the other end of the first annular inclined surface 43; the inner diameter of the end of the second annular inclined surface 44 close to the valve port 21 is smaller than the inner diameter of the other end of the second annular inclined surface 44.

[0077] It can be understood that from the end of the first annular inclined surface 43 close to the valve port 21 to the end away from the valve port 21, the inner diameter gradually becomes smaller; from the end of the second annular section 42 close to the valve port 21 to the end away from the valve port 21, the inner diameter gradually becomes smaller. The flow area of the medium gradually becomes smaller from the second annular inclined surface 44 to the first annular inclined surface 43, enabling the medium to flow smoothly along the first annular inclined surface 43 and the second annular inclined surface 44, and the medium will not generate a large impact on the retaining ring 40 due to the sudden change of the flow area.

[0078] Preferably, the end surface of the first annular section 41 in stop fit with the piston 30 is perpendicular to the movement direction of the piston 30.

[0079] As Figure 3 shown, the outer ring of the end of the piston 30 close to the retaining ring 40 has an arc surface 36, and the part of the arc surface 36 close to the end surface of the piston 30 abuts against the end surface of the first annular section 41 close to the valve port 21.

[0080] When the piston 30 engages the retaining ring 40, the curved surface 36 reduces impact and provides a certain degree of guidance. The portion where the curved surface 36 connects to the end face of the piston 30 makes surface contact with the end face of the first annular segment 41, avoiding line contact between the curved surface 36 and the first annular segment 41 and preventing excessive inclination at the contact point, which could cause the piston 30 and retaining ring 40 to become stuck.

[0081] like Figure 1 As shown, the valve seat portion includes a valve tube 10 and a valve seat 20 . The outer ring of the valve seat 20 is connected to the inner wall of the valve tube 10 . The valve seat 20 has a valve port 21 . The piston 30 is movably disposed in the valve tube 10 to open and close the valve port 21 .

[0082] The piston 30 is movably disposed in the valve tube 10 . The valve seat 20 and the retaining ring 40 are respectively disposed on both sides of the piston 30 to limit the piston 30 in the valve tube 10 . The piston 30 is driven by the pressure difference on both sides to open and close the valve port 21 .

[0083] Optionally, in a specific embodiment of the present invention, the valve tube 10, the valve seat 20, the piston 30 and the retaining ring 40 are all made of cast iron or steel, and both ends of the valve tube 10 are respectively welded to the external tube made of cast iron or steel.

[0084] The valve pipe 10 and the external pipe are both made of cast iron or steel, and can be directly connected to the external pipe by welding. Compared with the prior art method of arranging sleeves at both ends of the valve pipe 10 and connecting the valve pipe 10 to the external pipe through the sleeves, the welding method saves costs and simplifies the process.

[0085] The valve pipe 10, valve seat 20, piston 30 and retaining ring 40 are all made of cast iron or steel, so that the valve pipe 10 and the external pipe can be connected by integral furnace welding, which is convenient, fast and cost-effective.

[0086] Preferably, the valve tube 10 , the valve seat 20 , the piston 30 , the retaining ring 40 and the external tube can be made of carbon steel or stainless steel.

[0087] like Figure 8 and Figure 9 As shown, the external tube includes a first external tube and a second external tube. The first external tube is connected to one end of the valve tube 10 close to the retaining ring 40, and the second external tube is connected to one end of the valve tube 10 close to the valve seat 20. The valve tube 10 has a first positioning surface 121 and a second positioning surface 122. The first positioning surface 121 is used to position the retaining ring 40. The end of the retaining ring 40 facing away from the valve port 21 abuts against the first external tube, and the second positioning surface 122 is used to position the second external tube.

[0088] The first positioning surface 121 is used to limit the retaining ring 40, and indirectly limit the first outer connecting pipe at the same time. The second positioning surface 122 is used to limit the second outer connecting pipe, avoiding the excessive insertion depth during the connection of the first outer connecting pipe and the second outer connecting pipe to the valve pipe 10 respectively, interfering with the piston 30, and affecting the normal use of the one-way valve.

[0089] Optionally, the first positioning surface 121 can be set to directly position the first outer connecting pipe, and the end surface of the retaining ring 40 close to the first outer connecting pipe is flush with the first positioning surface 121; the valve seat 20 can be set to abut against the second positioning surface 122, and the end surface of the valve seat 20 facing away from the piston 30 abuts against the second outer connecting pipe.

[0090] As Figure 7 shown, the valve pipe 10 includes a first connecting section 11, a second connecting section 12 and a third connecting section 13 connected in sequence. The first outer connecting pipe is connected to the first connecting section 11, the second outer connecting pipe is connected to the third connecting section 13, the first positioning surface 121 is arranged on the end surface of the second connecting section 12 close to the first connecting section 11, and the second positioning surface 122 is arranged on the end surface of the second connecting section 12 close to the third connecting section 13.

[0091] The first positioning surface 121 positions the first outer connecting pipe, and the second positioning surface 122 positions the second outer connecting pipe. The structure of the valve pipe 10 itself is used to position the first outer connecting pipe and the second outer connecting pipe, which is convenient and fast. At the same time, the insertion lengths of the first outer connecting pipe and the second outer connecting pipe into the valve pipe 10 are limited.

[0092] It can be understood that the first positioning surface 121 and the second positioning surface 122 can be arranged on the inner wall or the outer wall of the valve pipe 10, and the outer connecting pipe is inserted into the valve pipe 10 or sleeved on the outer periphery of the valve pipe 10.

[0093] As Figure 9 shown, the end surface of the valve seat 20 facing away from the piston 30 is flush with the second positioning surface 122, and the outer ring of the valve seat 20 is laser welded annularly with the inner wall of the second connecting section 12 close to the third connecting section 13.

[0094] The end surface of the valve seat 20 facing away from the piston 30 is flush with the second positioning surface 122 for laser welding between the valve seat 20 and the valve pipe 10. The outer ring of the valve seat 20 is closely attached to the inner wall of the valve pipe 10 for laser welding. In this way, when welding between the second outer connecting pipe and the valve pipe 10, the solder cannot penetrate into the inner wall of the second connecting section 12 along the gap between the valve seat 20 and the valve pipe 10, thus avoiding the solder affecting the smoothness of the inner wall of the second connecting section 12 and the flexible movement of the piston 30 in the valve pipe 10.

[0095] Optionally, the outer ring of the retaining ring 40 is connected to the inner wall of the valve pipe 10 by means of annular laser welding. The outer ring of the retaining ring 40 is in interference fit with the inner wall of the valve pipe 10 so that the retaining ring 40 is closely attached to the valve pipe 10, making the laser welding more firm.

[0096] As Figure 9 shown, the outer ring of the valve seat 20 is connected to the inner wall of the valve pipe 10. One end of the inner ring of the valve seat 20 close to the piston 30 has a first annular flow guiding surface 22, and the first annular flow guiding surface 22 is used for guiding the medium flowing into the valve port 21. One end of the inner side of the valve seat 20 facing away from the piston 30 has a second annular flow guiding surface 23, and the second annular flow guiding surface 23 is used for guiding the medium into the valve port 21.

[0097] The first annular flow guiding surface 22 guides the medium flowing into the valve port 21, and the second annular flow guiding surface 23 guides the medium into the valve port 21, so that the medium flows along the first annular flow guiding surface 22 and the second annular flow guiding surface 23, and the flow area of the medium gradually changes, avoiding a large impact on the medium caused by a sudden change in the flow area.

[0098] As Figure 9 shown, the cross-section of the valve seat 20 along the axis direction of the check valve is the valve seat cross-section. The included angle between the two sides of the first annular flow guiding surface 22 in the valve seat cross-section is the first included angle 221, and the included angle between the two sides of the second annular flow guiding surface 23 in the valve seat cross-section is the second included angle 231. The range of the first included angle 221 is 50° to 100°, and the range of the second included angle 231 is 50° to 100°.

[0099] With this setting, the range of the first included angle 221 is 50° to 100°, and the range of the second included angle 231 is 50° to 100°. Within this range, the flow capacity of the medium when flowing through the valve port 21 is better. Moreover, when the ranges of the first included angle 221 and the second included angle 231 are 50° to 100°, the change in the flow area of the medium is relatively slow, making the flow of the medium relatively gentle and not likely to cause a large impact.

[0100] In a specific embodiment of the present invention, a valve group device is provided, which includes a first external connecting pipe, a second external connecting pipe and the above-mentioned check valve. The first external connecting pipe is connected to one end of the valve pipe 10 of the check valve close to the retaining ring 40 of the check valve, the second external connecting pipe is connected to one end of the valve pipe 10 close to the valve seat 20, and the valve pipe 10, valve seat 20, piston 30 and retaining ring 40 of the check valve are made of cast iron or steel, and the first external connecting pipe and the second external connecting pipe are made of cast iron or steel.

[0101] The valve tube 10 can be connected to the first external connecting tube and the second external connecting tube by welding. Compared with the prior art where the materials of the first external connecting tube, the second external connecting tube and the valve tube 10 cannot be directly welded, copper sleeves are connected to both ends of the valve tube 10, and then the copper sleeves are used to connect to the first external connecting tube and the second external connecting tube. The welding method is simpler, more convenient and faster.

[0102] Further, the first external connecting tube is connected to the valve tube 10 by furnace welding, and the second external connecting tube is connected to the valve tube 10 by furnace welding.

[0103] The valve tube 10, valve seat 20, piston 30 and retaining ring 40 of the one-way valve are made of cast iron or steel, and the valve tube 10 can be integrally furnace welded with the first external connecting tube and the second external connecting tube.

[0104] Optionally, the valve tube 10 can also be connected to the first external connecting tube and the second external connecting tube by laser welding.

[0105] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

[0106] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or their combinations.

[0107] Unless otherwise specifically stated, the relative arrangements of the components and steps, numerical expressions and values set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that for the convenience of description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationship. Technologies, methods and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods and devices should be regarded as part of the specification. In all the examples shown and discussed here, any specific value should be interpreted as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0108] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom", etc. is usually based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description. Without contrary explanation, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the protection scope of the present utility model; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0109] For ease of description, spatial relative terms such as "above...", "over...", "on the upper surface of...", "above-mentioned", etc. can be used here to describe the spatial positional relationship between a device or feature shown in the drawings and other devices or features. It should be understood that the spatial relative terms are intended to include different orientations in use or operation in addition to the orientation described in the drawings for the device. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "over other devices or structures" will then be positioned "below other devices or structures" or "under other devices or structures". Thus, the exemplary term "above..." can include both the orientations of "above..." and "below...". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding interpretations should be made for the spatial relative descriptions used here.

[0110] In addition, it should be noted that using words such as "first", "second", etc. to limit components is only for the convenience of distinguishing the corresponding components. Without otherwise stating, these words have no special meaning. Therefore, it should not be construed as a limitation on the protection scope of the present utility model.

Claims

1. A check valve, characterized in that, Comprising: A valve seat portion, one end of the valve seat portion having a valve port (21); A piston (30), the piston (30) being movably disposed within the valve seat portion to open and close the valve port (21), the piston (30) including a piston body (31) and a guiding structure (32), the piston body (31) being a shell-like structure, the guiding structure (32) being connected to the outer periphery of the piston body (31), and the guiding structure (32) being in sliding fit with the valve seat portion.

2. The one-way valve according to claim 1, characterized in that, The piston body (31) includes a flow-through section (311), a plugging section (312), and a diversion section (313) connected in sequence. The outer diameter of the flow-through section (311) is less than or equal to the inner diameter of the valve port (21), the outer diameter of the plugging section (312) is greater than the inner diameter of the valve port (21), the outer diameter of the diversion section (313) is less than the outer diameter of the plugging section (312), the diversion section (313) is disposed on a side of the plugging section (312) away from the valve port (21), and the plugging section (312) is used to plug the valve port (21).

3. The one-way valve according to claim 2, wherein, A cross-section of the piston (30) along the axis direction of the one-way valve is a piston cross-section. An angle between two sides of the flow-through section (311) in the piston cross-section is a flow angle (33), and the range of the flow angle (33) is 50° to 100°.

4. The one-way valve according to claim 1, characterized in that, The thickness range of the shell wall of the piston body (31) is 0.3 mm to 1.5 mm.

5. The one-way valve according to claim 1, characterized in that, The material of the piston (30) is cast iron or steel material.

6. The one-way valve according to claim 5, characterized in that, The valve seat portion includes a valve tube (10) and a valve seat (20). The outer ring of the valve seat (20) is connected to the inner wall of the valve tube (10). The valve seat (20) has the valve port (21). The piston (30) is movably disposed within the valve tube (10) to open and close the valve port (21). The one-way valve further includes a retaining ring (40). The retaining ring (40) is disposed on a side of the piston (30) away from the valve port (21). The valve tube (10), the valve seat (20), and the retaining ring (40) are made of cast iron or steel material.

7. The one-way valve according to claim 1, characterized in that, The guiding structure (32) includes a plurality of sheet-like structures (321). The plurality of sheet-like structures (321) are distributed along the outer periphery of the piston body (31) and fixed to the piston body (31). The outer side wall of the sheet-like structure (321) is in sliding fit with the valve seat portion. Along the axial direction of the one-way valve, the length of the piston (30) is N, and the distance between one end of the sheet-like structure (321) away from the valve port (21) and one end of the piston body (31) away from the valve port (21) is M. The ratio range of M to N is 0.35 to 0.

7.

8. The one-way valve according to claim 1, characterized in that, The one-way valve further includes a retaining ring (40). The retaining ring (40) is disposed on a side of the piston (30) facing away from the valve port (21). The retaining ring (40) is fixed within the valve seat portion. The retaining ring (40) is used to stop the piston (30). The retaining ring (40) includes a first annular segment (41). The inner diameter of the first annular segment (41) is smaller than the outer diameter of the piston (30). An end face of the first annular segment (41) close to the valve port (21) is in stop fit with an end face of the piston (30) facing away from the valve port (21).

9. The one-way valve according to claim 8, characterized in that, The retaining ring (40) further includes a second annular segment (42). The second annular segment (42) is connected to an end face of the first annular segment (41) close to the valve port (21). The inner diameter of the second annular segment (42) is larger than the inner diameter of the first annular segment (41). The guiding structure (32) includes a plurality of sheet-like structures (321). An end of the sheet-like structure (321) facing away from the valve port (21) has a constricted section (3213). The constricted section (3213) can be inserted into the inner ring of the second annular segment (42).

10. The one-way valve according to claim 9, characterized in that, The outer sides of the constricted sections (3213) of the plurality of sheet-like structures (321) are located on the same annular circle. The diameter of the annular circle is E. The inner diameter of the second annular segment (42) is F. F is greater than E. The difference range between E and F is 0.3 mm to 1.5 mm.

11. The check valve according to claim 1, characterized in that, The piston (30) is processed by powder metallurgy; or, the piston (30) is processed by die molding.

Images