Post-treatment noise elimination structure suitable for natural gas vehicle type
By introducing high-frequency pipes, sound-absorbing cotton and backpressure valves into the after-treatment and sound-absorbing structure of natural gas models, combining the bending of the outside air pipe and the V-shaped bracket, the noise problem of natural gas models is solved, and effective noise suppression and exhaust quality improvement are achieved.
Patent Information
- Application Number
- CN202422545646.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-22
- Publication Date
- 2025-07-25
- Estimated Expiration
- 2034-10-22
AI Technical Summary
In driving, natural gas models have problems such as failing to meet the standards and high low-frequency roar in the car. The existing valve body structure has poor matching performance at high flow and high temperature, resulting in low-frequency noise suppression but high-frequency noise amplification or increased back pressure, and the valve body is prone to breakage.
The sound-absorbing part is adopted, including high-frequency tubes and high-frequency sound-absorbing cotton, combined with a back pressure valve, absorbs low-frequency and high-frequency noise, connects through the bend of the outer air pipe and the V-shaped bracket to extend the exhaust path, increase the length of the sound-absorbing structure, and use the heat-insulating cotton to absorb heat, optimize the back pressure valve structure to reduce pressure difference.
Effectively suppress low-frequency noise, absorb high-frequency noise, solve the problem of roar in the car, while keeping the exhaust path length unchanged, reducing back pressure, avoiding valve body breakage, and improving exhaust quality.
Smart Images
Figure CN223152129U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of engine exhaust, in particular to a post-processing silencer structure suitable for natural gas vehicle models. Background Art
[0002] At present, the after-treatment volume of high-horsepower gas engines is about 100L, mainly including removable box-type platforms, pull-out box-type platforms, S-type cylindrical platforms, U-shaped tight-coupled platforms, etc.; but with the compact layout of the whole vehicle, under the balance of high performance and low cost, and under the requirements of airflow uniformity, low back pressure, emission limits, etc. of the after-treatment, a cylindrical platform solution is designed, with a volume of about 40-60L.
[0003] Compared with the traditional box-type platform, the structure adjustment space of the silencer module is smaller, resulting in the problem of substandard passing noise and loud low-frequency roar in the natural gas vehicle during driving.
[0004] In combination with the design requirements of the cylindrical structure, a valve body is added to the silencer module to control the low-frequency noise. However, the valve body structure is not well matched to the high flow and high temperature of natural gas vehicles, and often leads to low-frequency noise suppression but high-frequency noise amplification, or a large increase in back pressure, or valve body structure breakage and other problems. Summary of the invention
[0005] In view of the shortcomings of the prior art, the utility model provides a post-processing noise reduction structure suitable for natural gas vehicles, which comprehensively adjusts the post-processing noise reduction structure, absorbs low-frequency noise and high-frequency noise, and solves the roar problem in the vehicle. The technical solution adopted by the utility model is:
[0006] A post-processing silencer structure applicable to a natural gas vehicle, comprising a post-processing part, an outgoing air pipe, a silencer, and a back pressure valve, wherein the upstream end of the outgoing air pipe is connected to the outlet end of the post-processing part, and the downstream end thereof is connected to the inlet end of the silencer, and the back pressure valve is arranged at the connection between the outgoing air pipe and the silencer;
[0007] The muffler portion includes a high-frequency tube, an air outlet connecting tube, and high-frequency sound-absorbing cotton. The high-frequency tube and the air outlet connecting tube are nested inside and outside, and the high-frequency sound-absorbing cotton is filled between the high-frequency tube and the air outlet connecting tube.
[0008] Furthermore, the outgoing air pipe is bent so that the post-processing part and the muffler part are parallel, and the muffler part is connected to the post-processing part via a V-shaped bracket.
[0009] Furthermore, an oxygen sensor is arranged inside the outgoing air pipe.
[0010] Further, the post-treatment part includes a post-treatment inner cylinder, an air inlet end cover, an air outlet end cover, and a TWC catalytic converter. The air inlet end cover and the air outlet end cover are respectively arranged at the air inlet end and the air outlet end of the post-treatment inner cylinder, and at least two TWC catalytic converters are arranged in sequence along the air flow direction in the post-treatment inner cylinder.
[0011] Further, an outer post-treatment cylinder is nested outside the post-treatment inner cylinder, and heat insulation cotton is filled between the post-treatment inner cylinder and the outer post-treatment cylinder.
[0012] Further, an inner intake pipe is installed inside the post-treatment inner cylinder at the air inlet end cover. A plurality of intake holes are arranged on the side surface of the inner intake pipe facing the TWC catalytic converter, and the exhaust gas enters the post-treatment inner cylinder through the end of the inner intake pipe and the intake holes in sequence.
[0013] Further, an outer intake pipe connected to the inner intake pipe is installed outside the post-treatment inner cylinder at the air inlet end cover. An intake flange is arranged at one end of the outer intake pipe away from the air inlet end cover.
[0014] Further, an inner outlet pipe connected to the outer outlet pipe is installed inside the post-treatment inner cylinder at the air outlet end cover. A plurality of outlet holes are arranged on the side surface of the inner outlet pipe facing the TWC catalytic converter, and the exhaust gas is discharged from the post-treatment inner cylinder through the outlet holes and the end of the inner outlet pipe in sequence.
[0015] Further, a transverse bracket is arranged horizontally on the outer surface of the post-treatment outer cylinder; and / or, a longitudinal bracket is arranged vertically on the outer surface of the post-treatment outer cylinder.
[0016] Further, an outlet flange is arranged at one end of the outlet connection pipe away from the outer outlet pipe.
[0017] Advantages of the present utility model:
[0018] Through the cooperation of the muffler part and the back pressure valve, it is possible to both suppress low-frequency noise by using the back pressure valve and absorb high-frequency noise brought by the back pressure valve, solving the problem of interior booming;
[0019] The arrangement of the outlet elbow makes the total length of the entire post-treatment muffler structure unchanged, but the exhaust path is lengthened, which is beneficial to eliminating interior booming;
[0020] The heat is absorbed by the heat insulation cotton and the post-treatment outer cylinder. Description of the drawings
[0021] Figure 1 is a schematic diagram of the structural composition of the present utility model.
[0022] Figure 2 is a cross-sectional view of the present utility model.
[0023] Figure 3 This is the structural diagram of the internal intake pipe of the present utility model.
[0024] In the figure: 1 - post - treatment part, 110 - inner cylinder of post - treatment, 120 - intake end - cover, 130 - outlet end - cover, 140 - TWC catalytic converter, 150 - heat - insulating cotton, 160 - outer cylinder of post - treatment, 170 - internal intake pipe, 180 - internal outlet pipe, 2 - external outlet pipe, 210 - oxygen sensor, 3 - muffler part, 310 - high - frequency pipe, 320 - outlet connecting pipe, 330 - high - frequency sound - absorbing cotton, 340 - outlet flange, 4 - back - pressure valve, 5 - external intake pipe, 510 - intake flange, 6 - V - shaped bracket, 7 - transverse bracket, 8 - longitudinal bracket. Specific embodiments
[0025] In order to make the objectives, technical solutions and advantages of the present utility model clearer, the following further details the present utility model in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.
[0026] Please refer to the attached Figure 1-2 The present utility model provides a post - treatment muffler structure applicable to natural - gas vehicle models, including a post - treatment part 1, an external outlet pipe 2, a muffler part 3, and a back - pressure valve 4. The upstream end of the external outlet pipe 2 is connected to the outlet end of the post - treatment part 1, and its downstream end is connected to the intake end of the muffler part 3. The back - pressure valve 4 is arranged at the connection between the external outlet pipe 2 and the muffler part 3. The muffler part 3 includes a high - frequency pipe 310, an outlet connecting pipe 320, and high - frequency sound - absorbing cotton 330. The high - frequency pipe 310 and the outlet connecting pipe 320 are arranged with inner and outer nesting, and the high - frequency sound - absorbing cotton 330 is filled between the high - frequency pipe 310 and the outlet connecting pipe 320.
[0027] The exhaust gas is first treated by the post - treatment part 1, then enters the muffler part 3 through the external outlet pipe 2. After the muffler part 3 absorbs the noise, the exhaust gas is discharged from the end of the outlet connecting pipe 320 and enters the downstream equipment. The back - pressure valve 4 is opened under the action of the exhaust pressure to suppress low - frequency noise, and the high - frequency pipe 310 and the high - frequency sound - absorbing cotton 330 absorb the high - frequency noise brought by the back - pressure valve 4, solving the problem of interior rumbling.
[0028] In a specific connection relationship, one end of the outlet connecting pipe 320 is fixedly welded to the external outlet pipe 2, and the end of the high - frequency pipe 320 is tightly fitted with the inner wall of the outlet connecting pipe 320. The exhaust gas can only enter the high - frequency pipe 320 from the external outlet pipe 2 and does not directly contact the high - frequency sound - absorbing cotton 330.
[0029] Preferably, since the exhaust temperature is relatively high, adjusting the valve body size of the back pressure valve 4 and increasing the exhaust flow area can reduce the pressure difference between the front and rear pipelines of the back pressure valve 4. Secondly, by adjusting the torsion spring angle of the back pressure valve 4 to adapt to the exhaust gas flow velocity and the pipe diameter of the high-frequency pipe 310, the absorption effect of high-frequency noise can be further improved.
[0030] Preferably, the valve disc shape of the back pressure valve 4 is configured as a circle, so that the aperture of the valve disc at the high-flow opening angle and other apertures is as large as possible, which can increase the exhaust flow area and avoid the problem of the valve body falling off caused by the large pressure difference between the front and rear pipelines of the back pressure valve.
[0031] Furthermore, in order to facilitate the installation and connection of the muffler part 3 and the downstream equipment, an outlet flange 340 is provided at one end of the outlet connecting pipe 320 away from the outlet pipe 2.
[0032] In the present application, the outlet pipe 2 is bent to make the post-treatment part 1 and the muffler part 3 parallel, and the muffler part 3 is connected to the post-treatment part 1 through a V-shaped bracket 6. In a specific embodiment, the outlet end of the post-treatment part 1 is located on the side of the post-treatment part 1 and is perpendicular to the axis of the post-treatment part 1. By configuring the shape of the outlet pipe 2 as a bent pipe, the total length of the entire post-treatment and muffler structure remains unchanged, but the exhaust path is lengthened, and in cooperation with the structure of the muffler part 3, the in-vehicle roar is further eliminated.
[0033] In one embodiment, an oxygen sensor 210 is provided inside the outlet pipe 2. The oxygen sensor 210 can detect the pollutant content in the exhaust gas to ensure the exhaust gas quality.
[0034] In the present application, the post-treatment part 1 includes a post-treatment inner cylinder 110, an inlet end cover 120, an outlet end cover 130, and a TWC catalyst 140. The inlet end cover 120 and the outlet end cover 130 are respectively arranged at the inlet end and the outlet end of the post-treatment inner cylinder 110, and at least two TWC catalysts 140 are arranged in sequence along the gas flow direction inside the post-treatment inner cylinder 110. In a specific embodiment, the post-treatment inner cylinder, the inlet end cover 120, and the outlet end cover 130 are welded to form a sealed chamber. The exhaust gas enters from the side of the inlet end cover 120 and exits from the side of the outlet end cover 130. Two TWC catalysts 140 are press-fitted and over-fitted inside the post-treatment inner cylinder 110, and the generated CO, HC, NO X etc. are absorbed by the TWC catalyst 140, and at the same time, the honeycomb shape of the TWC catalyst 140 is used to absorb noise.
[0035] Furthermore, a post-treatment outer cylinder 160 is nested outside the post-treatment inner cylinder 110, and heat insulation cotton 150 is filled between the post-treatment inner cylinder 110 and the post-treatment outer cylinder 160. The post-treatment outer cylinder 160 and the post-treatment inner cylinder 110 implement a double-layer structure design for the cylinder structure, and the heat insulation cotton 150 filled in the middle prevents the temperature of the outer surface of the post-treatment part 1 from being too high.
[0036] The intake structure of the post-treatment part 1 is specifically configured as follows: An inner intake pipe 170 is installed at the intake end cover 120 and inside the post-treatment inner cylinder 110. A plurality of intake holes are provided on the side of the inner intake pipe 170 facing the TWC catalyst 140. Exhaust gas first passes through the end of the inner intake pipe 170 and then enters the post-treatment inner cylinder 110 through the intake holes. In one embodiment, please refer to the appendix Figure 2 and the appendix Figure 3 , the inner intake pipe 170 is horizontally arranged and perpendicular to the axis of the post-treatment inner cylinder 110. Exhaust gas enters its interior from the end of the inner intake pipe 170 and then enters the post-treatment inner cylinder 110 through the intake holes on its upper side; the shapes of the intake holes include square and circular, and the aperture sizes are large and small. Preferably, square holes are arranged in the middle of the inner intake pipe 170, and circular holes are arranged on the axial two sides of the square holes, aiming to evenly distribute the exhaust gas flow, make the contact between the exhaust gas and the TWC catalyst 140 more uniform, and avoid the problem that part of the TWC catalyst 140 is damaged after long-term use due to uneven exhaust gas flow.
[0037] To facilitate the connection between the post-treatment part 1 and the upstream equipment, an outer intake pipe 5 connected to the inner intake pipe 170 is installed at the intake end cover 120 and outside the post-treatment inner cylinder 110. An intake flange 510 is provided at the end of the outer intake pipe 5 away from the intake end cover 120. In a specific embodiment, the outer intake pipe 5 is fixedly welded to one end of the inner intake pipe 170, and the intake flange 510 is used to dock with the upstream equipment and is detachably connected.
[0038] The outlet structure of the post-treatment part 1 is specifically configured as follows: An inner outlet pipe 180 connected to the outer outlet pipe 2 is installed at the outlet end cover 130 and inside the post-treatment inner cylinder 110. A plurality of outlet holes are provided on the side of the inner outlet pipe 180 facing the TWC catalyst 140. Exhaust gas is discharged from the post-treatment inner cylinder 110 through the outlet holes and then through the end of the inner outlet pipe 180. In one embodiment, the inner outlet pipe 180 is horizontally arranged and perpendicular to the axis of the post-treatment inner cylinder 110. Exhaust gas enters the interior of the inner outlet pipe 180 through the outlet holes on the lower side of the inner outlet pipe 180 and then is discharged from its end; the shape of the exhaust hole is square or circular, and the aperture size is adjusted according to the diameter of the back pressure valve and the muffler part 3, which is used to comprehensively eliminate low-frequency and high-frequency noises.
[0039] In the present application, for the convenience of better fitting and fixing the sound absorption structure with the vehicle body, a transverse bracket 7 is arranged on the outer surface of the post-treatment outer cylinder 160 along the transverse direction; a longitudinal bracket 8 is arranged on the outer surface of the post-treatment outer cylinder 160 along the longitudinal direction.
[0040] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the examples, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.
Claims
1. A post-treatment silencing structure applicable to natural gas vehicle models, characterized in that: It includes a post-treatment part (1), an outlet air pipe (2), a silencing part (3), and a back pressure valve (4). The upstream end of the outlet air pipe (2) is connected to the air outlet end of the post-treatment part (1), and its downstream end is connected to the air inlet end of the silencing part (3). The back pressure valve (4) is arranged at the connection between the outlet air pipe (2) and the silencing part (3). The silencing part (3) includes a high-frequency pipe (310), an outlet connection pipe (320), and high-frequency sound-absorbing cotton (330). The high-frequency pipe (310) and the outlet connection pipe (320) are arranged with inner and outer nesting, and the high-frequency sound-absorbing cotton (330) is filled between the high-frequency pipe (310) and the outlet connection pipe (320).
2. The post-treatment muffler structure applicable to natural gas vehicle models according to claim 1, characterized in that: The outlet air pipe (2) is bent so that the post-treatment part (1) and the silencing part (3) are parallel, and the silencing part (3) is connected to the post-treatment part (1) through a V-shaped bracket (6).
3. The post-treatment muffler structure applicable to natural gas vehicle models according to claim 1, characterized in that: An oxygen sensor (210) is arranged inside the outlet air pipe (2).
4. The post-treatment muffler structure applicable to natural gas vehicle models according to any one of claims 1-3, characterized in that: The post-treatment part (1) includes a post-treatment inner cylinder (110), an inlet end cover (120), an outlet end cover (130), and a TWC catalytic converter (140). The inlet end cover (120) and the outlet end cover (130) are respectively arranged at the inlet end and the outlet end of the post-treatment inner cylinder (110), and at least two TWC catalytic converters (140) are arranged in sequence along the air flow direction inside the post-treatment inner cylinder (110).
5. The post-treatment muffler structure applicable to natural gas vehicle models according to claim 4, characterized in that: A post-treatment outer cylinder (160) is nested outside the post-treatment inner cylinder (110), and heat insulation cotton (150) is filled between the post-treatment inner cylinder (110) and the post-treatment outer cylinder (160).
6. The post-treatment silencing structure applicable to natural gas vehicle models according to claim 4, characterized in that: An inner inlet pipe (170) is installed at the inlet end cover (120) and inside the post-treatment inner cylinder (110). A plurality of inlet holes are arranged on the side surface of the inner inlet pipe (170) facing the TWC catalytic converter (140), and the exhaust gas enters the post-treatment inner cylinder (110) through the end of the inner inlet pipe (170) and the inlet holes in sequence.
7. The post-treatment silencing structure applicable to natural gas vehicle models according to claim 6, characterized in that: An outer inlet pipe (5) connected to the inner inlet pipe (170) is installed at the inlet end cover (120) and outside the post-treatment inner cylinder (110). An inlet flange (510) is arranged at one end of the outer inlet pipe (5) away from the inlet end cover (120).
8. The post-treatment muffler structure applicable to natural gas vehicle models according to claim 4, wherein: An inner outlet pipe (180) connected to the outlet air pipe (2) is installed at the outlet end cover (130) and inside the post-treatment inner cylinder (110). A plurality of outlet holes are arranged on the side surface of the inner outlet pipe (180) facing the TWC catalytic converter (140), and the exhaust gas is discharged from the post-treatment inner cylinder (110) through the outlet holes and the end of the inner outlet pipe (180) in sequence.
9. The post-treatment muffler structure applicable to natural gas vehicle models according to claim 5, characterized in that: A transverse bracket (7) is arranged horizontally on the outer surface of the post-treatment outer cylinder (160); and / or, a longitudinal bracket (8) is arranged vertically on the outer surface of the post-treatment outer cylinder (160).
10. The post-treatment silencing structure applicable to natural gas vehicle models according to any one of claims 1-3, characterized in that: An outlet flange (340) is arranged at one end of the outlet connection pipe (320) away from the outlet air pipe (2).