Exhaust passive valve for vehicle

Abstract

The utility model provides a kind of exhaust passive valve for vehicle, comprising: valve body assembly, comprising: mounting seat, for being set on exhaust pipe, valve body, one side of the valve body is fixedly connected with the mounting seat, the valve body includes through-hole, the through-hole is through the valve body, and gas flow is passed through;Shaft assembly, comprising rotating shaft, the rotating shaft extends along first direction, and it is set on the mounting seat and can rotate freely;Elastic component, the elastic component connects the rotating shaft with the valve body assembly;Valve piece, one side of the valve piece is fixedly connected with the rotating shaft, the valve piece can cover or open the through-hole, counterweight is equipped on the valve piece.The utility model embodiment provides exhaust passive valve for vehicle low in cost, torsional spring installation state is good, can overcome small and medium flow working condition product tremor problem, product torque characteristic consistent performance is good.

Description

Technical Field

[0001] This utility model belongs to the technical field of engine exhaust system, and in particular relates to a passive exhaust valve for vehicles. Background Technology

[0002] As drivers seek a more comfortable driving experience, the demand for noise suppression in automobiles is gradually increasing. As a core component of the automotive muffler unit, the exhaust passive valve plays a crucial role in controlling low- and mid-frequency noise. With hybrid vehicles increasingly dominating the market, exhaust muffler systems are becoming more constrained by the boundaries of the vehicle chassis, trending towards reduced volume. Therefore, the development of passive valves to replace the muffler volume is receiving increasing attention.

[0003] Conventional mufflers in automotive exhaust systems can reduce mid-to-high frequency noise from engine exhaust, but their effect on low-frequency noise is not significant. Using a passive exhaust valve can effectively reduce low-frequency noise and improve the overall NVH performance of the vehicle. The passive exhaust valve assembly is installed within the muffler housing. The passive valve's spring force keeps the valve plate in the closed position. When the exhaust pressure is high enough to overcome the spring force, the valve plate opens. The greater the exhaust back pressure, the larger the opening angle of the passive valve. When the exhaust pressure decreases, the spring returns the valve plate to the closed position. By adjusting the spring angle, the torque applied to the valve plate can be adjusted to meet the pressure requirements under different operating conditions.

[0004] However, in actual use, the changes in the combustion flow inside the engine will cause unstable airflow pulses in the entire exhaust system (each with its own characteristics under small, medium and large flow conditions). Under the impact of these unstable airflows, the moving parts (valve plates) in the exhaust valve will easily vibrate at a certain frequency with the airflow, which will cause corresponding abnormal noises in the muffler system. This will affect the subjective evaluation of the vehicle and the noise sound pressure level index, which is something that needs to be avoided in the field of NVH. Summary of the Invention

[0005] To address at least one technical problem in the prior art, this utility model provides a passive exhaust valve for vehicles with high reliability. To achieve the above technical objectives, the technical solution adopted by this utility model is as follows: This utility model embodiment provides a passive exhaust valve for vehicles, including: Valve body assembly, including: Mounting bracket for mounting on the exhaust pipe. A valve body, one side of which is fixedly connected to the mounting base, the valve body includes a through hole that penetrates the valve body and allows airflow to pass through; A pivot assembly includes a pivot extending in a first direction and rotatably mounted on the mounting base; An elastic component, wherein the elastic component connects the rotating shaft and the valve body assembly; A valve plate, one side of which is fixedly connected to the rotating shaft, is capable of covering or opening the through hole, and is provided with a counterweight.

[0006] Furthermore, the mounting base is U-shaped, with the opening of the U-shaped mounting base facing the valve body. One end of the rotating shaft is rotatably connected to one end of the mounting base, and the other end of the rotating shaft passes through the other end of the mounting base and is located outside the mounting base; The elastic component includes a torsion spring, which is disposed outside the mounting base and fitted with the rotating shaft. One end of the torsion spring is fixedly connected to the mounting base, and the other end of the torsion spring is fixedly connected to the end of the rotating shaft away from the mounting base.

[0007] Furthermore, the valve body assembly also includes: The first plug is fixedly connected to one end of the mounting base. The first plug includes a first protrusion that protrudes toward the side away from the mounting base, and the first protrusion contains a first receiving cavity. The second plug is fixedly connected to the other end of the mounting base. The second plug includes a second protrusion that protrudes toward the side away from the mounting base, and the second protrusion contains a second receiving cavity. The rotating shaft assembly also includes: The first bearing is disposed in the first accommodating cavity; A second bearing is disposed in the second accommodating cavity, and the first bearing and / or the second bearing is sleeved on the rotating shaft.

[0008] Furthermore, the rotating shaft is provided with a first limiting part and a second limiting part, the first limiting part and / or the second limiting part protruding radially along the rotating shaft, the first limiting part and the second limiting part being spaced apart along a first direction and disposed between the first bearing and the second bearing. The rotating shaft assembly also includes: A first spring washer is sleeved on the rotating shaft and disposed between the first limiting part and the first bearing; The second spring washer is sleeved on the rotating shaft and disposed between the second limiting part and the second bearing.

[0009] Furthermore, the mounting base near the end of the torsion spring also includes an extension, the extension having a first groove. The second protrusion is fitted onto one end of the torsion spring near the mounting base; The pin of the torsion spring near the mounting base is engaged in the first groove.

[0010] Furthermore, the rotating shaft assembly also includes a cap body, which is disposed at the end of the rotating shaft away from the first plug, and the opening of the cap body faces the mounting base; The cap body is provided with at least one second groove; The pin at the end of the torsion spring furthest from the mounting base engages in the second groove.

[0011] Furthermore, the cap body is square; The cap body is provided with four second grooves, and any one of the second grooves is located at one corner of the cap body.

[0012] Furthermore, the rotating shaft assembly also includes a spring support seat, which is disposed within the cap body. The bottom of the spring support is fixedly connected to the inner wall of the cap body, and the middle part of the spring support protrudes towards the mounting base to form a first protrusion; The first protrusion is fitted onto the end of the torsion spring away from the mounting base.

[0013] Furthermore, the vehicle exhaust passive valve also includes a gasket. The gasket is fixedly connected to the valve body and is disposed between the valve body and the valve plate.

[0014] Furthermore, the valve plate is also provided with: A positioning groove, wherein the positioning groove is used for positioning the counterweight; Assembly hole, the assembly hole being used to assemble the counterweight.

[0015] The beneficial effects of the technical solution provided by this utility model embodiment are: The passive exhaust valve for vehicles provided in this embodiment of the invention utilizes a torsion spring designed between the rotating shaft and the mounting base to apply an initial preload to the valve plate. The first protrusion of the spring mounting base and the second protrusion of the second end cap ensure that the torsion spring only undergoes standard torsion in the circumferential direction when the valve plate rotates, avoiding inconsistencies caused by lateral torsion of the torsion spring. A first spring washer is designed between the first limiting part and the first bearing of the rotating shaft, and a second spring washer is designed between the second limiting part and the second bearing to increase the torsional damping of the rotating shaft, reducing wear during long-term operation and minimizing vibrations caused by unstable airflow. A counterweight is welded to the valve plate, and its mass is adjusted to eliminate valve plate resonance caused by different engine characteristics in different vehicle models. The passive exhaust valve for vehicles provided in this embodiment of the invention is low in cost, has excellent torsion spring installation, overcomes product vibration problems under small to medium flow conditions, and exhibits good consistency in product torque characteristics. Attached Figure Description

[0016] Figure 1This is a schematic diagram of the structure of the passive exhaust valve for vehicles in this embodiment of the present invention.

[0017] Figure 2 This is a cross-sectional view of the vehicle exhaust passive valve in an embodiment of this utility model.

[0018] Figure 3 This is a schematic diagram of the structure of the passive exhaust valve for vehicles in this embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0020] In the description of the embodiments of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components; and they can refer to a wireless connection or a wired connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0022] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0023] This utility model embodiment provides a passive exhaust valve for vehicles, including: Valve body assembly 1 includes: Mounting bracket 11 is used for mounting on the exhaust pipe. The valve body 12 has one side fixedly connected to the mounting base 11. The valve body 12 includes a through hole that passes through the valve body 12 and allows airflow to pass through. The rotating shaft assembly 2 includes a rotating shaft 21, which extends along a first direction A and is rotatably mounted on the mounting base 11; Elastic component 3, which connects the rotating shaft 21 and the valve body assembly 1; Valve plate 4, one side of which is fixedly connected to the rotating shaft 21, the valve plate 4 can cover or open the through hole, and a counterweight 6 is provided on the valve plate 4.

[0024] In a specific embodiment, such as Figure 1 , Figure 2 As shown, the valve body 12 has a through hole. Since the rotating shaft 21 is rotatably connected to the mounting base 11 and the upper edge of the valve plate 4 is fixedly connected to the rotating shaft 21, when the airflow passes through the through hole, it will drive the valve plate 4 to rotate, causing the valve plate 4 to open the through hole. At the same time, the valve plate 4 drives the rotating shaft 21 to rotate. Furthermore, since the elastic component 3 connects the rotating shaft 21 and the valve body assembly 1, when the rotating shaft 21 rotates, the elastic component 3 deforms and has a tendency to return to its original shape. When the airflow decreases or disappears, the elastic component 3 returns to its original shape, causing the rotating shaft 21 to return to its initial state, thereby driving the valve plate 4 to rotate. At this time, the valve plate 4 closes the through hole.

[0025] The valve plate 4 is provided with the counterweight 6, which can be made of low carbon material through powder metallurgy. The counterweight 6 can overcome the resonance of the valve plate 4 caused by airflow fluctuations, and improve the safety and stability of the vehicle exhaust passive valve.

[0026] The specific configuration of the elastic component 3 described in this application is not limited. In one specific embodiment, the mounting base 11 is U-shaped, and the opening of the U-shaped mounting base 11 faces the valve body 12. One end of the rotating shaft 21 is rotatably connected to one end of the mounting base 11, and the other end of the rotating shaft 21 passes through the other end of the mounting base 11 and is located outside the mounting base 11; The elastic component 3 includes a torsion spring 31, which is disposed outside the mounting base 11 and sleeved on the rotating shaft 21. One end of the torsion spring 31 is fixedly connected to the mounting base 11, and the other end of the torsion spring 31 is fixedly connected to the end of the rotating shaft 21 away from the mounting base 11.

[0027] In a specific embodiment, such as Figure 1 , Figure 2As shown, the opening of the mounting base 11 faces downwards, the rotating shaft 21 extends in the left-right direction, the right end of the rotating shaft 21 is rotatably connected to the right end of the mounting base 11, the left end of the rotating shaft 21 passes through the left end of the mounting base 11 and extends to the left, the torsion spring 31 is sleeved on the rotating shaft 21, the right end of the torsion spring 31 is fixedly connected to the left end of the mounting base 11, and the left end of the torsion spring 31 is fixedly connected to the left end of the rotating shaft 21. In this structure, the torsion spring 31 can generate an initial preload force on the rotating shaft 21, thereby generating an initial preload force on the valve plate 4. By adjusting the initial preload force of the torsion spring 31, the initial preload force required for the valve plate 4 to open the through hole can be adjusted.

[0028] The manner in which the rotating shaft 21 is rotatably connected to the mounting base 11 is not limited. In one specific embodiment, the valve body assembly 1 further includes: The first plug 13 is fixedly connected to one end of the mounting base 11. The first plug 13 includes a first protrusion, which protrudes toward the side away from the mounting base 11. The first protrusion has a first receiving cavity inside. The second plug 14 is fixedly connected to the other end of the mounting base 11. The second plug 14 includes a second protrusion, which protrudes toward the side away from the mounting base 11, and the second protrusion contains a second receiving cavity. The rotating shaft assembly 2 also includes: The first bearing 22 is disposed in the first accommodating cavity; The second bearing 23 is disposed in the second accommodating cavity, and the first bearing 22 and / or the second bearing 23 are sleeved on the rotating shaft 21.

[0029] In a specific embodiment, such as Figure 1 and Figure 2 As shown, the right end of the mounting base 11 is provided with the first plug 13, the first boss of the first plug 13 protrudes to the right, and the first receiving cavity formed by the first boss is provided with the first bearing 22. Similarly, the left end of the mounting base 11 is provided with the second plug 14, the second boss of the second plug 14 protrudes to the left, and the second receiving cavity formed by the second boss is provided with the second bearing 23. The right end of the rotating shaft 21 is connected to the first plug 13 through the first bearing 22, and the left end of the rotating shaft 21 passes through the second bearing 23 and is connected to the second plug 14. This structure is simple, and the rotating shaft 21 can be rotatably connected to the mounting base 11.

[0030] Furthermore, the rotating shaft 21 is provided with a first limiting part 211 and a second limiting part 212, the first limiting part 211 and / or the second limiting part 212 protruding radially along the rotating shaft 21, the first limiting part 211 and the second limiting part 212 being spaced apart along a first direction (A) and disposed between the first bearing 22 and the second bearing 23. The rotating shaft assembly 2 also includes: The first spring washer 24 is sleeved on the rotating shaft 21 and is disposed between the first limiting part 211 and the first bearing 22; The second spring washer 25 is sleeved on the rotating shaft 21 and is located between the second limiting part 212 and the second bearing 23.

[0031] like Figure 1 and Figure 2 As shown, the first limiting part 211 and the second limiting part 212 play a limiting role. The first limiting part 211 facilitates the quick positioning and installation of the first spring washer 24, the first bearing 22, and the first plug 13, while the second limiting part 212 facilitates the quick positioning and installation of the second spring washer 25, the second bearing 23, and the second plug 14.

[0032] During installation, firstly, apply lubricating grease to the first bearing 22 and the second bearing 23. Then, sequentially fit the first spring washer 24 and the first bearing 22 onto the rotating shaft 21 from the right end to the left. Simultaneously, sequentially fit the second spring washer 25 and the second bearing 23 onto the rotating shaft 21 from the left end to the right. Next, use a clamping fixture to fit the first plug 13 onto the right end of the rotating shaft 21, so that the first bearing 22 is placed in the first accommodating cavity. Then, fit the second plug 14 onto the left end of the rotating shaft 21, so that the second bearing 23 is placed in the second accommodating cavity. Finally, weld the first plug 13 to the mounting base 11 and the second plug 14 to the mounting base 11, respectively.

[0033] The first spring washer 24 and the second spring washer 25 can increase the torsional damping of the rotating shaft 21, reduce the wear caused by long-term operation of the rotating shaft 21, and reduce the vibration caused by unstable airflow.

[0034] The vehicle exhaust passive valve is mounted on the exhaust pipe via the mounting base 11 and placed inside the muffler. When the engine speed is low, the airflow inside the muffler is small, and the airflow blows from one side towards the valve plate 4. At this time, the back pressure is small, and the initial preload of the torsion spring 31 is greater than the airflow back pressure. At this time, the valve plate 4 closes the through hole, and the exhaust gas flows out from other gaps inside the muffler. Thus, this structure can produce a good suppression effect on low-frequency noise. When the engine speed gradually increases to a certain range, the back pressure gradually increases and overcomes the initial preload of the torsion spring 31. At this time, the valve opens at a small angle, allowing some airflow to flow out through the through hole. At this time, the vehicle exhaust passive valve still has a good suppression effect on mid-to-low frequency noise. When the engine speed further increases and the flow rate is larger, the back pressure completely overcomes the initial preload of the torsion spring 31, and the valve is fully opened. At this time, most of the airflow can flow out through the through hole. This structure is simple and reasonably designed, and can simultaneously meet the requirements of high power and low fuel consumption.

[0035] Furthermore, the mounting base 11 further includes an extension 111 at one end near the torsion spring 31, and the extension 111 is provided with a first groove 11a. The second boss is fitted onto one end of the torsion spring 31 near the mounting base 11; The pin of the torsion spring 31 near the mounting base 11 is engaged in the first groove 11a.

[0036] In a specific embodiment, such as Figure 1 and Figure 2 As shown, the left end of the mounting base 11 is the second plug 14. On the second plug 14, the second boss protrudes to the left, and the extension 111 extends to the left. The right end of the torsion spring 31 is fitted with the second boss, and the pin is inserted into the first groove 11a on the extension 111. Thus, the position of the right end of the torsion spring 31 is kept fixed, and the second boss can limit the right end of the torsion spring 31 to only rotate circumferentially, so as to prevent the right end of the torsion spring 31 from rotating laterally.

[0037] Furthermore, the rotating shaft assembly 2 also includes a cap 26, which is disposed at the end of the rotating shaft 21 away from the first plug 13, and the opening of the cap 26 faces the mounting base 11; The cap body 26 is provided with at least one second groove 26a; The pin of the torsion spring 31 at the end away from the mounting base 11 is engaged in the second groove 26a.

[0038] like Figure 1 and Figure 2As shown, the opening of the cap 26 faces to the right, and the pin at the left end of the torsion spring 31 is inserted into the second groove 26a, thereby keeping the position of the left end of the torsion spring 31 fixed.

[0039] The specific configuration of the cap body 26 is not limited; in one specific embodiment, the cap body 26 is square. The cap body 26 is provided with four second grooves 26a, and any one of the second grooves 26a is located at one corner of the cap body 26.

[0040] The specific configuration of the second groove 26a is not limited. Furthermore, any second groove 26a on the cap body 26 extends in the left-right direction and then in the circumferential direction.

[0041] Furthermore, the rotating shaft assembly 2 also includes a spring support seat 27, which is disposed within the cap body 26. The bottom of the spring support 27 is fixedly connected to the inner wall of the cap 26, and the middle part of the spring support 27 protrudes toward the mounting base 11 and forms a first protrusion. The first protrusion is fitted onto the end of the torsion spring 31 away from the mounting base 11.

[0042] like Figure 1 and Figure 2 As shown, the first protrusion of the spring support 27 protrudes to the right, and the left end of the torsion spring 31 is fitted with the first protrusion. Since the right end of the torsion spring 31 is fitted with the second protrusion, the first protrusion of the spring support 27 and the second protrusion of the second plug can ensure that the torsion spring 31 only undergoes standard torsion in the circumferential direction when the valve plate 4 rotates, thus avoiding the problem of poor consistency caused by lateral torsion of the torsion spring 31.

[0043] The bottom of the spring support 27 is fixedly connected to the inner wall of the cap body 26. Furthermore, the bottom of the spring support 27 is quadrilateral. By selecting any two points on the diagonal of the bottom of the spring support 27 and welding them to the inner wall of the bottom of the cap body 26, the spring support 27 and the cap body 26 can be connected and fixed.

[0044] In this embodiment, during installation, the required preload angle of the torsion spring 31 is determined according to the operating conditions. The cap 26 is fitted onto the left end of the rotating shaft 21, so that the left end of the torsion spring 31 fits onto the first protrusion of the spring mounting seat 11 inside the cap 26, achieving secondary positioning. The pin of the left end of the torsion spring 31 is then inserted into a second groove 26a. After manually rotating the left end of the torsion spring 31 to the required position using a torsion spring 31 rotating wrench, the left end of the rotating shaft 21 is welded and fixed to the cap 26, thereby ensuring that the position of the left end of the torsion spring 31 remains fixed.

[0045] Furthermore, the vehicle exhaust passive valve also includes a gasket 5. The gasket 5 is fixedly connected to the valve body 12 and is disposed between the valve body 12 and the valve plate 4.

[0046] In a specific embodiment, such as Figure 2 As shown, the gasket 5 can buffer the valve plate 4, preventing elastic collisions between the valve plate 4 and the valve body 12. During installation, the gasket 5 and the valve body 12 are spot-welded together using a spot welding fixture. The gasket 5 can be made of densely pressed metal wire.

[0047] The quantity, mass, size, and position of the counterweights 6 described in this application are not limited. The quantity, mass, size, and position of the counterweights 6 can be adaptively adjusted according to actual needs. Furthermore, the valve plate 4 is also provided with: Positioning groove 4a, the positioning groove 4a is used for positioning the counterweight 6; Assembly hole 4b is used to assemble the counterweight 6.

[0048] like Figure 3 As shown, during installation, the positioning groove 4a facilitates the rapid positioning of the counterweight 6. The upper side of the counterweight 6 is aligned with the lower side of the positioning groove 4a, and the counterweight 6 is welded to the valve plate 4 through the assembly hole 4b.

[0049] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although this utility model has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A passive exhaust valve for vehicles, characterized in that, include: Valve body assembly (1) includes: Mounting bracket (11) is used to install on the exhaust pipe. A valve body (12) is fixedly connected to the mounting base (11) on one side. The valve body (12) includes a through hole that passes through the valve body (12) and allows airflow to pass through. The rotating shaft assembly (2) includes a rotating shaft (21) that extends along a first direction (A) and is rotatably mounted on the mounting base (11); Elastic component (3), the elastic component (3) connects the rotating shaft (21) and the valve body assembly (1); A valve plate (4) is fixedly connected to the rotating shaft (21) on one side. The valve plate (4) can cover or open the through hole. A counterweight (6) is provided on the valve plate (4).

2. The vehicle exhaust passive valve as described in claim 1, characterized in that, The mounting base (11) is U-shaped, and the opening of the U-shaped mounting base (11) faces the valve body (12). One end of the rotating shaft (21) is rotatably connected to one end of the mounting base (11), and the other end of the rotating shaft (21) passes through the other end of the mounting base (11) and is located outside the mounting base (11); The elastic component (3) includes a torsion spring (31), which is located outside the mounting base (11) and fitted with the rotating shaft (21). One end of the torsion spring (31) is fixedly connected to the mounting base (11), and the other end of the torsion spring (31) is fixedly connected to the end of the rotating shaft (21) away from the mounting base (11).

3. The vehicle exhaust passive valve as described in claim 2, characterized in that, The valve body assembly (1) also includes: The first plug (13) is fixedly connected to one end of the mounting base (11). The first plug (13) includes a first protrusion, which protrudes toward the side away from the mounting base (11). The first protrusion has a first receiving cavity inside. The second plug (14) is fixedly connected to the other end of the mounting base (11). The second plug (14) includes a second protrusion, which protrudes toward the side away from the mounting base (11). The second protrusion contains a second receiving cavity. The rotating shaft assembly (2) also includes: The first bearing (22) is disposed in the first accommodating cavity; The second bearing (23) is disposed in the second accommodating cavity, and the first bearing (22) and / or the second bearing (23) are sleeved on the rotating shaft (21).

4. The vehicle exhaust passive valve as described in claim 3, characterized in that, The rotating shaft (21) is provided with a first limiting part (211) and a second limiting part (212). The first limiting part (211) and / or the second limiting part (212) protrude radially along the rotating shaft (21). The first limiting part (211) and the second limiting part (212) are spaced apart along a first direction (A) and are located between the first bearing (22) and the second bearing (23). The rotating shaft assembly (2) also includes: The first spring washer (24) is sleeved on the rotating shaft (21) and disposed between the first limiting part (211) and the first bearing (22); The second spring washer (25) is sleeved on the rotating shaft (21) and disposed between the second limiting part (212) and the second bearing (23).

5. The vehicle exhaust passive valve as described in claim 3, characterized in that, The mounting base (11) near the end of the torsion spring (31) also includes an extension (111), on which a first groove (11a) is provided. The second boss is fitted onto one end of the torsion spring (31) near the mounting base (11); The pin of the torsion spring (31) near the mounting base (11) is engaged in the first groove (11a).

6. The vehicle exhaust passive valve as described in claim 3, characterized in that, The rotating shaft assembly (2) also includes a cap (26), which is located at one end of the rotating shaft (21) away from the first plug (13), and the opening of the cap (26) faces the mounting base (11). The cap body (26) is provided with at least one second groove (26a); The pin of the torsion spring (31) at the end away from the mounting base (11) is engaged in the second groove (26a).

7. The vehicle exhaust passive valve as described in claim 6, characterized in that, The cap body (26) is square; The cap body (26) is provided with four second grooves (26a), and any one of the second grooves (26a) is located at one corner of the cap body (26).

8. The vehicle exhaust passive valve as described in claim 6, characterized in that, The rotating shaft assembly (2) further includes a spring support seat (27), which is disposed in the cap body (26). The bottom of the spring support (27) is fixedly connected to the inner wall of the cap (26), and the middle part of the spring support (27) protrudes toward the mounting base (11) and forms a first protrusion. The first protrusion is fitted onto the end of the torsion spring (31) away from the mounting base (11).

9. The vehicle exhaust passive valve as described in claim 1, characterized in that, The vehicle exhaust passive valve also includes a gasket (5). The gasket (5) is fixedly connected to the valve body (12) and is located between the valve body (12) and the valve plate (4).

10. The vehicle exhaust passive valve as described in claim 1, characterized in that, The valve plate (4) is also provided with: Positioning groove (4a), the positioning groove (4a) is used for positioning the counterweight (6); Assembly hole (4b) for assembling the counterweight (6).

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