CN114658901B

CN114658901B - Mute check valve

Info

Publication number: CN114658901B
Application number: CN202210424444.2A
Authority: CN
Inventors: 陈才尚
Original assignee: Taizhou Shangyi Valve Co ltd
Current assignee: Taizhou Shangyi Valve Co ltd
Priority date: 2022-04-22
Filing date: 2022-04-22
Publication date: 2022-10-25
Anticipated expiration: 2042-04-22
Also published as: CN114658901A

Abstract

The utility model relates to a silence check valve, relate to check valve technical field, which comprises a valve body, set up inlet and liquid outlet on the valve body, it is provided with the valve rod to slide in the valve body, be equipped with the disk seat that supplies the valve rod both ends to slide and run through in the valve body, there is the slip clearance between valve rod and the disk seat, the valve rod is close to the one end fixed connection of inlet has the valve clack, the cover is equipped with reset spring on the valve rod between valve clack and the disk seat, reset spring butt respectively in disk seat and valve clack, reset spring is used for supporting the valve clack with the inlet shutoff, be equipped with the bush in the disk seat, the valve rod slides all the time and runs through in the bush. This application reduces the damage that the valve rod received through setting up the bush, the striking of buffer valve rod and disk seat, and then reduces the noise that the valve rod struck to produce in the disk seat to have the advantage that reduces the check valve use and produce the noise.

Description

Mute check valve

Technical Field

The application relates to the technical field of check valves, in particular to a mute check valve.

Background

The present check valve is a valve whose opening and closing piece is a circular valve clack and acts by its own weight and medium pressure to block the medium from flowing backwards, and mainly plays a role in protecting other fluid machines and pipelines from safety by stopping the fluid from flowing backwards.

In the traditional check valve, the valve rod is driven by the valve clack to slide in the valve seat, the valve clack is flushed by fluid under the action of the spring, and the valve seat is closed by the flowing action of the spring and the fluid on the valve clack under the condition of counter-flow of the fluid.

The inventor thinks that: after the check valve is used for a long time, due to abrasion and rusting, the sliding friction of the valve rod in the valve seat is increased, the sliding sound of the valve rod in the valve seat is easy to make larger, and therefore the check valve has noise in the using process.

Disclosure of Invention

In order to reduce the noise generated in the use process of the check valve, the application aims to provide a mute check valve.

The application provides a silence check valve adopts following technical scheme:

the utility model provides a silence check valve, includes the valve body, has seted up inlet and liquid outlet on the valve body, it is provided with the valve rod to slide in the valve body, be equipped with the disk seat that supplies the sliding through in valve rod both ends in the valve body, there is sliding gap between valve rod and the disk seat, the one end fixed connection that the valve rod is close to the inlet has the valve clack, the cover is equipped with reset spring on the valve rod between valve clack and the disk seat, reset spring butt in disk seat and valve clack respectively, reset spring is used for supporting the valve clack with the inlet shutoff, be equipped with the bush in the disk seat, the valve rod slide all the time run through in the bush.

Through adopting above-mentioned technical scheme, when using the check valve for a long time, rivers impact in the valve clack after getting into from the inlet for the valve clack receives to drive the valve rod after assaulting and slides towards the liquid outlet, so that reset spring compresses. So as to open the liquid inlet after separating the valve clack from the liquid inlet, and ensure that water flows from the liquid inlet to the liquid outlet. When the water impact on the valve clack, the valve clack slides and shakes in the valve body after receiving the impact of rivers for the valve rod collides with the bush in the disk seat, with the striking through bush buffer valve rod and disk seat, reduces the damage that the valve rod received, and then reduces the noise that the valve rod struck to produce in the disk seat, thereby reduces the noise that the check valve produced in the use.

Optionally, one side of valve clack towards the inlet inlays and is equipped with the gasket, be equipped with the sealing ring that is located inlet department in the valve body, the sealing ring is used for supporting tightly and seals the inlet in the gasket.

Through adopting above-mentioned technical scheme, when appearing against the current, rivers flow to the inlet from the liquid outlet, and then make reset spring act on the valve clack on, drive the valve clack and slide towards the inlet. So that the gasket slides along with the valve clack and then is tightly propped against the sealing ring to plug the liquid inlet, thereby enhancing the sealing property of the valve clack for plugging the liquid inlet.

Optionally, the valve body is provided with positioning blocks on the inner wall of the valve body, the valve clack and the gasket slide between the positioning blocks, a guide edge is arranged at the edge of the valve clack, and the guide edge allows the valve clack to slide between the positioning blocks.

Through adopting above-mentioned technical scheme, when rivers flowed to the liquid outlet from the inlet, the valve clack receives water impact and compression reset spring to drive the gasket and shift up, and make the guiding edge butt of valve clack in locating piece diapire. And then lead to the valve clack between the locating piece to make the gasket also slide between the locating piece, so that the valve clack receives the direction of locating piece when driving the valve rod and slide, make reset spring support the valve clack and drive gasket and sealing ring and support tightly, thereby improve the stability that the valve rod slided in the disk seat.

Optionally, the locating piece lower extreme slides and has the locating lever, the locating lever slides along the direction that the perpendicular to valve rod slided, be equipped with in the valve body and support the locating spring that the locating lever slided towards the valve rod, the one end butt that the locating spring was kept away from to the locating lever is in the circumference lateral wall of valve clack and gasket.

Through adopting above-mentioned technical scheme, on rivers flowed to the liquid outlet from the inlet, the valve clack received rivers to strike the back and drives the valve rod and slide towards the liquid outlet, and then makes the circumference lateral wall butt locating lever of valve clack to slide the locating lever towards the direction of keeping away from the valve rod, make the compression of positioning spring. Until the valve clack drives the gasket and all slips the locating lever, the locating spring drives the locating lever cunning and moves to one side of gasket back to the valve clack, so that the locating lever butt in the gasket, reduce the gasket, the slip of valve clack in the valve body, and then reduce the slip of valve rod, make the water that gets into from the inlet form the stable velocity of flow and flow out from the liquid outlet, on the other hand also fixes a position and leads to valve clack and the gasket that gets into the locating piece, make valve clack and gasket can slide into smoothly between the locating piece, thereby be convenient for the valve clack and the gasket slide into between the locating piece.

Optionally, the bottom wall of gasket is the arc, the locating lever butt is also the arc in the one end cross-section of valve clack.

Through adopting above-mentioned technical scheme, when rivers flowed to the inlet from the liquid outlet, rivers assaulted and drive the valve clack and slide towards the inlet on the valve clack, and reset spring acts on the valve clack simultaneously, drives valve clack and gasket and together slides towards the inlet for gasket slip butt is in the tip of locating lever, supports to move the locating lever towards the direction of keeping away from the valve rod. Make the locating lever slide butt in the circumference lateral wall of valve clack under positioning spring's effect, until gasket butt in sealing ring, with the inlet shutoff to prevent the liquid refluence in the valve body, thereby be convenient for valve clack, gasket follow roll-off between the locating piece.

Optionally, a flow guide body located at the upper end of the valve rod is arranged in the valve body, the flow guide body is located below a valve seat at the upper end of the valve rod, an inclined plane is arranged on the bottom wall of the flow guide body, the inclined plane is attached to the guide edge, the flow guide body is used for plugging the liquid inlet, and the valve clack is abutted to the rear of the flow guide body and the gasket is located between the positioning blocks.

Through adopting above-mentioned technical scheme, when the rivers impact force that gets into from the inlet is great, the valve clack receives the impact force after compression reset spring and slides towards the liquid outlet for valve clack and gasket are backed off behind the locating lever and are slided between the locating piece, and continue to slide to the liquid outlet. Until the guide edge on the valve clack abuts against the inclined plane on the flow guiding body, the gasket is still positioned between the positioning blocks at the moment so as to plug the liquid outlet through the abutting of the guide edge and the inclined plane, so that the pipeline behind the liquid outlet is prevented from being damaged due to large water flow impact, and the pipeline behind the liquid outlet is protected conveniently.

Optionally, a rotating shaft is arranged in the positioning block in a rotating mode, a locking rod is arranged on the side wall of the rotating shaft and rotates in the positioning block, a locking groove for allowing the end portion of the locking rod to rotate into is formed in the side wall of the positioning rod, and a driving piece for driving the rotating shaft to drive the locking rod to rotate into the locking groove is arranged in the positioning block.

Through adopting above-mentioned technical scheme, after the valve clack drove the gasket and slided the locating lever, the locating spring was decided the locating lever and is reseed, and the valve clack continues to drive the gasket and slides towards the liquid outlet this moment. Then the driving piece is started, the rotating shaft is driven to drive the locking rod to rotate, so that the locking rod rotates into the locking groove to lock the sliding of the positioning rod, and the sliding of the positioning rod is reduced. And then increase the stability of locating lever butt gasket for the gliding in-process of valve clack along with rivers, the locating lever homoenergetic supports and fixes a position the gasket, reduces the scope that valve clack and gasket removed, thereby improves the stability that the locating lever reduced valve clack, gasket sliding distance.

Optionally, the driving piece sets up in the epaxial actuating lever of commentaries on classics including the bending, the actuating lever upper end is crooked to the sliding path of valve clack on, the actuating lever is used for receiving the slip of valve clack and drives the locking lever and change over to the locking groove, when valve clack and gasket were located between actuating lever and the locating lever, the actuating lever received gravity to drive the locking lever and rotates out from the locking groove.

Through adopting above-mentioned technical scheme, when the valve clack drives the gasket and slides towards the liquid outlet, valve clack and gasket support slip in between the locating piece behind the locating lever, and the locating lever slides to one side that the gasket dorsad the valve clack under the positioning spring. Then the valve clack drives the gasket to continue to slide towards the liquid outlet until the valve clack butts against the driving rod, and the driving rod butts against the inside of the positioning block, so that the driving rod drives the rotating shaft to rotate, the locking rod on the rotating shaft is rotated into the locking groove on the positioning rod, the sliding of the positioning rod is locked, and the valve clack and the gasket can stably slide in the positioning block. Until the rivers that get into from the inlet reduce or rivers from the liquid outlet when getting into, reset spring acts on the valve clack, supports valve clack and drives the gasket and slide towards the inlet for valve clack and gasket slide the actuating lever, the actuating lever receives gravity to rotate from the locating piece, in order to drive the locking lever and follow locking inslot and rotate out, in order to relieve the slip locking of locating lever. And then be convenient for gasket and valve clack slide to open and slide towards the inlet behind the locating lever, support tightly in the sealing ring with the inlet shutoff until the gasket. Therefore, the driving rod is arranged, the driving rod is driven to rotate into the locking groove by being pushed by the valve clack, and after the valve clack is separated from the driving rod, the driving rod drives the locking rod to rotate out of the locking groove by gravity, so that the positioning rod is locked in a sliding mode and unlocked, and the sliding of the positioning rod is controlled conveniently.

In summary, the present application includes at least one of the following beneficial technical effects:

the impact of the valve rod and the valve seat is buffered by arranging the bushing, so that the damage to the valve rod is reduced, the noise generated when the valve rod impacts the valve seat is further reduced, and the noise generated in the use process of the check valve is further reduced;

through the arrangement of the positioning block, the valve clack and the gasket slide in the positioning block, so that the sliding of the valve rod and the valve clack is guided, the impact of the valve rod and the bushing is reduced, and the stability of the sliding of the valve rod in the valve seat is improved;

by arranging the positioning rod and the positioning spring, the sliding range of the valve clack and the valve rod is reduced, and the valve clack and the gasket entering the positioning block are positioned and guided, so that the valve clack and the gasket can smoothly slide between the positioning blocks, and the valve clack and the gasket can conveniently slide between the positioning blocks;

through the arrangement of the rotating shaft, the locking rod and the driving rod, the driving rod is driven to rotate into the locking groove by being pushed by the valve clack, and after the valve clack is separated from the driving rod, the driving rod is driven to rotate out of the locking groove by gravity, so that the sliding locking and unlocking of the positioning rod are realized, and the sliding of the positioning rod is controlled conveniently.

Drawings

Fig. 1 is a sectional view of the entire structure of an embodiment of the present application.

Fig. 2 is an enlarged schematic view of a portion a in fig. 1.

Description of reference numerals: 1. a valve body; 11. a liquid inlet; 12. a liquid outlet; 13. a valve seat; 131. a bushing; 14. a seal ring; 15. a flow conductor; 151. a bevel; 2. a valve stem; 21. a valve flap; 211. a guide edge; 22. a gasket; 23. a return spring; 3. positioning a block; 31. positioning a rod; 311. a locking groove; 32. a positioning spring; 33. a rotating shaft; 34. a locking lever; 35. a drive rod; 36. a first rotating groove; 37. and rotating the second groove.

Detailed Description

The present application is described in further detail below with reference to figures 1-2.

The embodiment of the application discloses a silence check valve.

Referring to fig. 1, the check valve includes a valve body 1, a liquid inlet 11 and a liquid outlet 12 provided on the valve body 1, a valve seat 13 is fixedly connected to an inner wall of the valve body 1 and is close to the liquid inlet 11 and the liquid outlet 12, and the valve seat 13 extends along a direction perpendicular to a flow direction of a fluid in the valve body 1.

Referring to fig. 1, the valve rod 2 is penetrated in the valve seat 13 along the vertical direction in a sliding manner, the upper end and the lower end of the valve rod 2 are both penetrated in the valve seat 13 in a sliding manner, a sliding gap is formed between the valve seat 13 and the valve rod 2, namely, a bushing 131 is fixedly connected to the valve seat 13 and sleeved on the valve rod 2, the valve rod 2 is always slid in the bushing 131, and a sliding gap is formed between the bushing 131 and the valve rod 2, so that the collision of the valve rod 2 in the sliding process and the valve seat 13 is reduced through the bushing 131.

Referring to fig. 1, the upper end of the valve rod 2 extends into the liquid outlet 12, the lower end extends into the liquid inlet 11, a valve flap 21 is integrally formed at one end of the valve rod 2 close to the liquid inlet 11, and the valve flap 21 is disc-shaped. A gasket 22 is embedded in the bottom wall of the valve flap 21 facing the liquid inlet 11, the joint of the bottom wall and the side wall of the gasket 22 is arc-shaped, and the gasket 22 is made of rubber materials.

Referring to fig. 1, a sealing ring 14 is fixedly connected to an inner wall of the liquid inlet 11 in the valve body 1, and the sealing ring 14 extends along the length direction of the valve rod 2 and then abuts against a side wall of the gasket 22 facing away from the valve flap 21. The upper end cover of valve rod 2 is equipped with reset spring 23, and the radial pitch of reset spring 23 reduces gradually along the direction of keeping away from valve clack 21.

Referring to fig. 1, the upper end of the return spring 23 abuts against the valve seat 13 at the upper end of the valve rod 2, and the lower end abuts against the valve flap 21, so that the valve flap 21 and the gasket 22 are abutted against the liquid inlet 11 by the urging of the return spring 23, and the gasket 22 is abutted against the sealing ring 14 to block the liquid inlet 11.

Referring to fig. 1, a flow guiding body 15 is also fixedly connected to an inner wall of the valve body 1 close to the liquid outlet 12, the flow guiding body 15 extends toward the sealing ring 14, an inclined surface 151 is disposed on a bottom wall of the flow guiding body 15, and a guiding edge 211 attached to the inclined surface 151 is disposed on a top wall of the valve flap 21. When the impact of water flow entering from the liquid inlet 11 is too large, the valve flap 21 moves upwards to abut the guide edge 211 against the inclined surface 151, so as to block the liquid outlet 12, thereby preventing the pipeline behind the liquid outlet 12 from being damaged due to the too large water flow.

Referring to fig. 1, the inner wall of the valve body 1 is fixedly connected with positioning blocks 3 located on two sides of the valve rod 2, the valve flap 21 drives the gasket 22 to slide between the positioning blocks 3 so as to guide the sliding of the valve flap 21 and the gasket 22 in the valve body 1, and the gasket 22 always slides between the positioning blocks 3, namely when the guide edge 211 abuts against the inclined surface 151, the gasket 22 is located between the positioning blocks 3.

Referring to fig. 1 and 2, a positioning rod 31 is slidably disposed at a lower end of the positioning block 3, the positioning rod 31 is slidably disposed in a direction perpendicular to the sliding direction of the valve rod 2, and a lower end of the positioning rod 31 extends below the positioning block 3. The inner wall of the valve body 1 is fixedly connected with a positioning spring 32, the end part of the positioning spring 32 is fixedly connected with a positioning rod 31 so as to enable the positioning rod 31 to abut against the valve clack 21 and the gasket 22 after abutting out of the positioning block 3, and the section of the end part of the positioning rod 31 far away from the positioning spring 32 is arc-shaped.

Referring to fig. 1, after the valve flap 21 and the gasket 22 are pushed against the positioning rod 31 to be away from each other, the valve flap 21 and the valve rod 2 are positioned by the pushing of the positioning rod 31, so that the valve flap 21 and the gasket 22 can smoothly slide between the positioning blocks 3. After the valve flap 21 and the gasket 22 slide over the positioning rod 31, the positioning rod 31 is reset under the urging of the positioning spring 32, so that the sliding range of the valve flap 21 and the gasket 22 is reduced after the positioning rod 31 slides into the positioning block 3, and water entering from the liquid inlet 11 forms a stable flow rate and flows out from the liquid outlet 12.

Referring to fig. 1 and 2, a rotating shaft 33 is rotatably connected to the positioning block 3, an axis of the rotating shaft 33 extends in a direction perpendicular to the sliding direction of the positioning rod 31, and an axis of the rotating shaft 33 is also perpendicular to the sliding direction of the valve rod 2. The side wall of the rotating shaft 33 is fixedly connected with a locking rod 34, the locking rod 34 is positioned below the rotating shaft 33, and a first rotating groove 36 for the locking rod 34 to rotate out is formed in the positioning block 3.

Referring to fig. 1 and 2, the locking lever 34 rotates above the positioning lever 31, and a locking groove 311 into which the locking lever 34 rotates is formed in a top wall of the positioning lever 31. The positioning blocks 3 are further provided with a driving member for driving the rotating shaft 33 to rotate the locking rod 34 into the locking slot 311, so as to lock the positioning spring 32 in a state of pushing the positioning rod 31 to slide between the positioning blocks 3.

Referring to fig. 1 and 2, the driving member includes a driving rod 35 fixedly connected to the rotating shaft 33, the driving rod 35 and the locking rod 34 are both disposed in a bent manner, the driving rod 35 is located above the locking rod 34, the driving rod 35 is bent toward the valve rod 2, and a second rotating groove 37 for allowing the upper end of the driving rod 35 to rotate out is formed in the positioning block 3, so that the driving rod 35 is driven by gravity to rotate the rotating shaft 33, further the locking rod 34 is driven to rotate out from the inside of the locking groove 311, and the sliding locking of the positioning rod 31 is released.

Referring to fig. 1 and 2, when the valve flap 21 slides towards the liquid outlet 12, the driving rod 35 is abutted, so that the driving rod 35 rotates into the second rotating groove 37, the rotating shaft 33 and the locking rod 34 are driven to rotate, the locking rod 34 rotates into the locking groove 311, the gasket 22 slides to the upper side of the positioning rod 31 along with the valve flap 21, the driving rod 35 is always abutted by the valve flap 21 or the gasket 22, and the sliding of the positioning rod 31 is locked, so that the sliding directions of the valve flap 21 and the gasket 22 are reduced. When the valve flap 21 and the gasket 22 slide towards the liquid inlet 11, the valve flap 21 is firstly separated from the driving rod 35, and the gasket 22 is abutted with the positioning rod 31, so that the gasket 22 abuts against the positioning rod 31 to be separated from each other after the positioning rod 31 is unlocked.

The implementation principle of the mute check valve in the embodiment of the application is as follows: when water flows into the liquid inlet 11 and flows out of the liquid outlet 12, the water flow impacts on the valve clack 21 to drive the valve clack 21 and the valve rod 2 to slide towards the liquid outlet 12, so that the water flows out of the liquid outlet 12 after the liquid inlet 11 is opened through the positioning block 3 and the flow guide body 15. Until the valve flap 21 abuts the detent lever 31 to move the detent lever 31 away from each other. The positioning rod 31 abuts against the side wall of the valve clack 21 under the action of the positioning spring 32 to centralize and position the valve clack 21 and the valve rod 2, so that the valve clack 21 drives the gasket 22 to smoothly slide into the positioning blocks 3. After the gasket 22 slides over the positioning rod 31, the positioning rod 31 is reset under the urging of the positioning spring 32, and the valve flap 21 continues to drive the gasket 22 to slide towards the liquid outlet 12. Until the valve flap 21 abuts against the driving rod 35, the rotating shaft 33 and the locking lever 34 are driven to rotate, so that the locking lever 34 rotates into the locking groove 311 to lock the sliding of the positioning lever 31. The valve flap 21 and the gasket 22 slide above the positioning rod 31 until the water flow impact is large, the valve flap 21 moves upwards to abut against the flow guiding body 15 so as to block the liquid outlet 12, and damage to a pipeline connected behind the liquid outlet 12 due to excessive water flow impact is avoided.

When the water flow is weakened or the water flow flows from the liquid outlet 12 to the liquid inlet 11, the valve flap 21 drives the gasket 22 to move towards the liquid inlet 11 until the gasket 22 is still above the positioning rod 31 after the valve flap 21 is separated from the driving rod 35. The drive lever 35 is rotated out of the positioning block 3 by gravity to disengage the lock lever 34 from the lock groove 311, thereby releasing the slide lock of the positioning lever 31. Then the return spring 23 acts on the valve flap 21, so that the gasket 22 pushes the positioning rods 31 away from each other to slide the valve flap 21 out of the positioning blocks 3 until the gasket 22 abuts against the sealing ring 14 to block the liquid inlet 11 and stop the backflow of the fluid. And in the sliding process of the valve rod 2, the impact of the valve rod 2 and the valve seat 13 is buffered through the bushing 131, the damage to the valve rod 2 is reduced, the noise generated when the valve rod 2 impacts the valve seat 13 is further reduced, and the noise generated in the use process of the check valve is reduced.

The above are preferred embodiments of the present application, and the scope of protection of the present application is not limited thereto, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. A quiet check valve characterized in that: the valve comprises a valve body (1), a liquid inlet (11) and a liquid outlet (12) are formed in the valve body (1), a valve rod (2) is arranged in the valve body (1) in a sliding mode, a valve seat (13) for the two ends of the valve rod (2) to slide through is arranged in the valve body (1), a sliding gap is formed between the valve rod (2) and the valve seat (13), a valve clack (21) is fixedly connected to one end, close to the liquid inlet (11), of the valve rod (2), a reset spring (23) is sleeved on the valve rod (2) between the valve clack (21) and the valve seat (13), the reset spring (23) is respectively abutted to the valve seat (13) and the valve clack (21), the reset spring (23) is used for abutting against the valve clack (21) to block the liquid inlet (11), a bushing (131) is arranged in the valve seat (13), and the valve rod (2) always slides through the bushing (131);

a gasket (22) is embedded in one side, facing the liquid inlet (11), of the valve flap (21), a sealing ring (14) located at the liquid inlet (11) is arranged in the valve body (1), and the sealing ring (14) is used for abutting against the gasket (22) to seal the liquid inlet (11);

the inner wall of the valve body (1) is provided with positioning blocks (3) positioned at two sides of the valve rod (2), the valve clack (21) and the gasket (22) slide between the positioning blocks (3), the edge of the valve clack (21) is provided with a guide edge (211), and the guide edge (211) is used for the valve clack (21) to slide between the positioning blocks (3);

a rotating shaft (33) is rotatably arranged in the positioning block (3), a locking rod (34) is arranged on the side wall of the rotating shaft (33), the locking rod (34) rotates in the positioning block (3), a locking groove (311) for the end part of the locking rod (34) to rotate in is formed in the side wall of the positioning block (31), and a driving part for driving the rotating shaft (33) to drive the locking rod (34) to rotate in the locking groove (311) is arranged in the positioning block (3);

the driving piece comprises a driving rod (35) which is arranged on the rotating shaft (33) in a bending mode, the upper end of the driving rod (35) bends to the sliding path of the valve clack (21), the driving rod (35) is used for driving the locking rod (34) to rotate into the locking groove (311) under the sliding effect of the valve clack (21), when the valve clack (21) and the gasket (22) are located between the driving rod (35) and the positioning rod (31), the driving rod (35) drives the locking rod (34) to rotate out of the locking groove (311) under the effect of gravity.

2. A silent check valve as claimed in claim 1, wherein: the valve body (1) is internally provided with a positioning spring (32) which can push the positioning rod (31) to slide towards the valve rod (2), and one end of the positioning rod (31), which is far away from the positioning spring (32), is abutted to the circumferential side wall of the valve clack (21) and the gasket (22).

3. A silent check valve as claimed in claim 2, wherein: the bottom wall of the gasket (22) is arc-shaped, and the section of one end, abutted to the valve flap (21), of the positioning rod (31) is also arc-shaped.

4. A silent check valve as claimed in claim 1, wherein: be equipped with in valve body (1) and be located flow guide body (15) of valve rod (2) upper end, flow guide body (15) are located disk seat (13) below of valve rod (2) upper end, flow guide body (15) diapire is equipped with inclined plane (151), inclined plane (151) laminate in leading limit (211), flow guide body (15) are used for carrying out the shutoff with inlet (11), valve clack (21) butt behind flow guide body (15) gasket (22) are located between locating piece (3).