Active and passive noise reduction silencer

Abstract

The invention discloses an active and passive noise reduction silencer, and relates to the technical field of noise reduction silencers, the active and passive noise reduction silencer comprises a noise reduction pipe, and a honeycomb turbulent flow noise reduction assembly, a spiral injection speed reduction assembly and a kinetic energy turbine conversion assembly are arranged in an inner cavity of the noise reduction pipe in the airflow flowing direction; efficient noise reduction and stable operation are realized through three processes of multi-stage speed reduction, active and passive cooperative noise reduction and kinetic energy conversion; through conical expansion of an inlet section pipeline, rectification and backflow interference of a honeycomb turbulent flow noise reduction assembly, and extension paths of a porous sound absorption confluence module and a spiral flow guide turning module of a spiral injection speed reduction assembly, multi-stage stepped speed reduction is formed, air flow kinetic energy and impact force are gradually reduced, and noise is further reduced; the porous sound absorption confluence module reduces airflow vibration noise through shunting and multiple sound absorption, the kinetic energy turbine conversion assembly converts airflow kinetic energy into mechanical kinetic energy, residual noise is accurately counteracted in cooperation with active noise reduction of the tail end of the noise reduction section pipeline, and the noise reduction effect is greatly improved through active and passive combination.

Description

Technical Field

[0001] The present invention relates to the technical field of noise reduction mufflers, in particular to an active and passive noise reduction muffler. Background Art

[0002] The noise generated during engine exhaust is closely related to the kinetic energy of the high-speed airflow, its flow stability, and the energy conversion method. Existing mufflers have shortcomings in these key aspects, which affect the noise reduction effect.

[0003] A Chinese patent with authorization publication number CN110657001B discloses a muffler, which includes a muffler shell, the muffler shell having a shell cover extending in the direction of the longitudinal axis of the shell, and the muffler having an outer bottom connected to the shell cover on each of the two axial end areas of the shell cover, wherein the shell cover and the outer bottom define a muffler inner chamber, and at least one inner bottom is arranged in the muffler inner chamber to divide the muffler inner chamber, the muffler also includes a muffler unit, the muffler unit having an inner pipe for guiding exhaust gas, an outer pipe surrounding the inner pipe, and a muffler material arranged between the inner pipe and the outer pipe.

[0004] The core cause of engine exhaust noise is the kinetic impact and turbulent flow of high-speed airflow. Existing mufflers have limitations in controlling this noise. Existing mufflers often rely on a single expansion or simple flow-guiding structure, lacking a stepped deceleration design. This allows high-speed airflow to maintain a strong impact upon entering, continuously impacting the internal structure and generating vibration noise.

[0005] In terms of airflow stability, when the airflow passes through the muffler, it is easy to have problems such as diversion chaos and local vortexes due to unreasonable guidance. These turbulent flows not only directly generate turbulent noise, but also reduce the effective contact efficiency between noise reduction components such as sound-absorbing cotton and the airflow, affecting the passive noise reduction effect.

[0006] To this end, the present invention proposes an active and passive noise reduction muffler to solve the above problems. Summary of the Invention

[0007] In view of the above problems in the prior art, the present invention is proposed.

[0008] To solve the above technical problems, the present invention provides the following technical solutions: To solve the above technical problems, the present invention provides the following technical solutions: An active and passive noise reduction muffler, comprising a noise reduction pipe, wherein the inner cavity of the noise reduction pipe is provided with a honeycomb turbulence noise reduction component, a spiral ejection speed reduction component and a kinetic energy turbine conversion component along the airflow direction;

[0009] The honeycomb spoiler and noise reduction component is used to divert and guide the airflow of the engine outlet pipe and interfere with the backflow to reduce the main airflow speed;

[0010] The spiral ejection deceleration component includes a porous sound absorption and confluence module and a spiral flow guide switch module. The porous sound absorption and confluence module absorbs airflow through its own porous structure to reduce noise. The spiral flow guide switch module includes a spiral rotation chamber to extend the airflow running distance and direct the airflow toward the kinetic energy turbine conversion component.

[0011] A kinetic energy turbine conversion component includes a flow guide hood, a spiral rotation module and a cutting and diversion module arranged in the flow guide hood. The airflow is directed toward the spiral rotation module through the flow guide hood to drive the spiral rotation module to rotate about its own axis. The rotating spiral rotation module stirs the flow guide hood to integrate the airflow, and the airflow hits the cutting and diversion module to cut the integrated airflow.

[0012] As a preferred solution of the active and passive noise reduction silencer described in the present invention, the honeycomb turbulence noise reduction component includes a first substrate and a second substrate in parallel, a reflux gap is formed between the first substrate and the second substrate, and a plurality of conical guide tubes are arranged in a through-array on the surface of the first substrate and the second substrate, a plurality of guide holes are provided in the middle area of ​​the first substrate, a reflux groove is provided in its edge area, and an overflow hole is provided on the surface of the second substrate.

[0013] As a preferred solution of the active and passive noise reduction muffler described in the present invention, the guide hole is a conical hole, the flared end of which faces the direction of the airflow, the cross-section of the reflow groove is arranged in a trapezoidal structure, the constricted end of the reflow groove faces the direction of the airflow, and the guide hole, the reflow groove and the overflow hole are arranged in an staggered manner with the conical guide tube.

[0014] As a preferred solution of the active and passive noise reduction silencer described in the present invention, the porous sound absorption convergence module includes a frame body, a diversion structure, a multi-stage sound absorption structure and a deflection structure. The frame body includes an upper frame and a lower frame. The upper frame and the lower frame form a chamber for accommodating the diversion structure and the multi-stage sound absorption structure. There are multiple multi-stage sound absorption structures, and the multiple multi-stage sound absorption structures are circumferentially arranged on the outside of the diversion structure. The upper frame is provided with a central groove and a rectangular through groove for the air flow to enter the diversion structure, and the side wall of the lower frame is provided with multiple side flow ports corresponding to the multiple diversion structures. The deflection structure is configured as multiple deflection plate groups installed at the side flow ports.

[0015] As a preferred solution of the active and passive noise reduction silencer described in the present invention, the deflector group includes a deflector bend, a mounting base for mounting the deflector bend on the outer wall of the lower frame, and sound-absorbing cotton laid on the deflector bend, and an air flow channel for air flow discharge is formed between two adjacent deflector bends. The cross-section of the air flow channel is arranged in a trapezoidal structure, and the flared end of the air flow channel faces the spiral guide switch module, so that the gas in the air flow channel is guided toward the spiral guide switch module.

[0016] As a preferred solution of the active and passive noise reduction silencer described in the present invention, the diversion structure includes a central base shaft installed at the center of the lower frame and a plurality of spiral bends installed on the central base shaft. The airflow is guided to the side flow port through the spiral bends and enters the airflow channel, and the surface of the spiral bends is covered with a layer of sound-absorbing material.

[0017] As a preferred solution of the active and passive noise reduction silencer described in the present invention, the multi-stage sound absorption structure includes a multi-opening mask installed at a rectangular through slot, the multi-opening mask is provided with a plurality of parallel porous sound-absorbing panels, and the multi-opening mask is provided with no less than two openings, one of the openings faces the rectangular through slot, and the other opening faces the air flow channel.

[0018] As a preferred solution of the active and passive noise reduction silencer described in the present invention, the spiral guide switching module includes a spiral guide tube with an opening, in which a first annular dividing tube plate and a second annular dividing plate are installed, and a spiral dividing piece is spirally arranged between the spiral guide tube and the first annular dividing plate, and an annular through groove is provided on the side of the first annular dividing tube plate close to the bottom of the spiral guide tube, and a plurality of circumferentially distributed jet tubes are provided at the bottom of the spiral guide tube, and the jet tubes are arranged obliquely at the bottom of the spiral guide tube, and the air inlet of the spiral guide tube faces the chamber surrounded by the second annular dividing plate.

[0019] As a preferred embodiment of the active and passive noise reduction muffler of the present invention, the drainage cover includes an upper loading plate and a lower loading plate parallel to each other, and an annular cylinder plate arranged outside the upper loading plate and the lower loading plate, a mounting shaft seat is arranged between the upper loading plate and the lower loading plate, and a plurality of jet grooves are opened on the upper loading plate, and the jet grooves correspond to the jet cylinders;

[0020] A diameter-changing cavity for accommodating the spiral rotation module and the cutting and diverting module is formed in the flow guide cover, and the annular cylinder plate is symmetrically formed by two conical annular plates.

[0021] As a preferred solution of the active and passive noise reduction muffler described in the present invention, the spiral rotation module includes a spiral shaft connected to the mounting shaft seat bearing of the upper loading plate, and a worm gear arranged on the spiral shaft; the cutting and diversion module includes a support column assembled on the mounting shaft seat of the downloading plate, a plurality of circumferentially distributed supporting plates installed on the support column, and triangular fins distributed on the surface of the supporting plate.

[0022] Beneficial effects of the present invention: The present invention achieves efficient noise reduction and stable operation through three processes: multi-stage deceleration, active and passive coordinated noise reduction, and kinetic energy conversion. The multi-stage stepped deceleration is formed by the conical expansion of the inlet section pipe, the rectification and backflow interference of the honeycomb spoiler noise reduction component, and the extension path of the porous sound absorption confluence module and the spiral guide switch module of the spiral injection deceleration component, thereby gradually reducing the airflow kinetic energy and impact force, thereby reducing noise generation; among them, the porous sound absorption confluence module reduces the airflow vibration noise by diversion and multiple sound absorption, and the kinetic energy turbine conversion component converts the airflow kinetic energy into mechanical kinetic energy to reduce the airflow impact noise. The active noise reduction at the tail end of the noise reduction section pipe accurately offsets the residual noise, and the active and passive combination greatly improves the noise reduction effect. In addition, the overflow hole of the honeycomb spoiler noise reduction component is used to balance the pressure, the spiral guide switch module is used for directional guidance, and the cutting diversion module is used for airflow integration to ensure the stability of the airflow flow and avoid local turbulence to generate secondary noise. While achieving efficient noise reduction, the exhaust resistance is not significantly increased, and both the noise reduction effect and the engine exhaust smoothness are taken into account. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 It is a schematic diagram of the overall structure of the active and passive noise reduction muffler in the present invention.

[0025] Figure 2 Schematic diagram of the internal structure of the noise reduction tube in the present invention.

[0026] Figure 3 It is a schematic diagram of the overall structure of the spiral ejection deceleration component in the present invention.

[0027] Figure 4 This is an axonometric view of the overall structure of the spiral ejection deceleration component in the present invention.

[0028] Figure 5 It is a schematic diagram of the overall structure of the porous sound absorption and confluence module in the present invention.

[0029] Figure 6 It is a schematic diagram of the overall structure of the spiral guide switch module in the present invention.

[0030] Figure 7 It is a schematic diagram of the overall structure of the kinetic energy turbine conversion component in the present invention.

[0031] Figure 8 It is a structural schematic diagram of the support column in the present invention.

[0032] Reference numerals: 110, inlet section pipe; 111, mainstream inlet; 120, noise reduction section pipe; 130, outlet section pipe; 131, mainstream outlet; 210, honeycomb turbulence noise reduction component; 211, first substrate; 212, second substrate; 213, conical guide tube; 214, guide hole; 215, return groove; 216, overflow hole; 220, spiral injection deceleration component; 230, kinetic energy turbine conversion component; 231, annular cylinder plate; 232, upper loading plate; 233, downloading plate; 234, mounting shaft seat; 235, spiral shaft; 236, worm plate; 237, triangular fin; 238, bearing plate; 2 39. Support column; 240. Multi-porous sound-absorbing convergence module; 2411. Multi-opening mask; 2412. Multi-porous sound-absorbing panel; 2421. Upper frame; 2422. Lower frame; 2423. Side flow port; 2424. Rectangular through groove; 2431. Baffle; 2432. Mounting base plate; 2433. Sound-absorbing cotton; 2441. Spiral bend; 2442. Central base axis; 250. Spiral guide switch module; 251. Spiral guide tube; 252. Spiral dividing piece; 253. First annular dividing tube plate; 254. Second annular dividing plate; 255. Annular through groove; 256. Jet tube; 300. Active noise reduction structure. DETAILED DESCRIPTION

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0034] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0035] Secondly, the term "one embodiment" or "embodiment" herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in various places throughout this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive of other embodiments.

[0036] Reference Figures 1-8 As shown, this embodiment provides an active and passive noise reduction muffler, which is installed on the engine exhaust pipe, and includes a noise reduction pipe, a honeycomb turbulence noise reduction component 210, a spiral ejection speed reduction component 220 and a kinetic energy turbine conversion component 230. The honeycomb turbulence noise reduction component 210, the spiral ejection speed reduction component 220 and the kinetic energy turbine conversion component 230 are coaxially arranged in the inner cavity of the noise reduction pipe along the airflow direction.

[0037] The noise reduction pipe includes an inlet section pipe 110, a noise reduction section pipe 120 and an outlet section pipe 130 which are connected in sequence. The inlet section pipe 110 is provided with a mainstream inlet 111, and the outlet section pipe 130 is provided with a mainstream outlet 131. The mainstream inlet 111 and the mainstream outlet 131 are opposite to each other and are located on the center line of the shell; wherein, the inlet section pipe 110 and the outlet section pipe 130 are conical cylinders, and the airflow of the engine exhaust pipe enters the conical expansion chamber of the inlet section pipe 110 through the mainstream inlet 111. The initial deceleration is achieved by means of the expansion effect of the chamber of the inlet section pipe 110 with the help of the conical structure. When the airflow diffuses in the chamber of the outlet section pipe, the kinetic energy is dispersed by the cavity space, and the flow velocity is suppressed by the first stage of the airflow velocity.

[0038] Reference Figure 1 and Figure 4 As shown, the honeycomb turbulence noise reduction component 210 is used to divert, guide and reflux the airflow of the engine exhaust pipe to reduce the main airflow speed; the honeycomb turbulence noise reduction component 210 includes a first substrate 211 and a second substrate 212 that are parallel to each other, and a reflux gap is formed between the first substrate 211 and the second substrate 212. The surface of the first substrate 211 and the second substrate 212 are arrayed with multiple conical guide tubes 213. After the airflow in the chamber of the inlet section pipe 110 enters the honeycomb turbulence noise reduction component 210, most of the airflow will flow along the gaps between the conical guide tubes 213 and flow directly to the connection area between the honeycomb turbulence noise reduction component 210 and the spiral injection speed reduction component 220. The array distribution of the conical guide tubes 213 can play a preliminary regularizing role on this part of the main airflow to avoid irregular diffusion of the airflow.

[0039] A plurality of guide holes 214 are provided in the central region of the first substrate 211, a reflow groove 215 is provided in the edge region thereof, and an overflow hole 216 is provided on the surface of the second substrate 212. The guide holes 214, the reflow groove 215, and the overflow hole 216 are arranged in an alternating manner with the conical guide tube 213; wherein, the guide hole 214 is a conical hole, the flared end of which faces the direction of the airflow, and the cross-section of the reflow groove 215 is arranged in a trapezoidal structure, the constricted end of which faces the direction of the airflow.

[0040] The multiple guide holes 214 in the central region of the first substrate 211 are tapered holes. The flared ends of the guide holes 214 face the direction of the airflow, receiving a portion of the main airflow and guiding it through the first substrate 211 into the return flow gap between the first substrate 211 and the second substrate 212. The return flow grooves 215 in the edge region have a trapezoidal cross-section, with the constricted ends facing the direction of the airflow. This can intercept the entry of the main airflow, but can easily guide the airflow in the return flow gap. The airflow passing through the guide holes 214 and the return flow grooves 215 will form a rotating airflow between the first substrate 211 and the second substrate 212. The rotating airflow will collide and interfere with the subsequent main airflow in the opposite direction, using the kinetic energy between the airflows to offset and further weaken the impact force of the main airflow, thereby reducing the overall velocity of the main airflow and performing the second stage of airflow velocity suppression.

[0041] Dense overflow holes 216 are opened on the surface of the second substrate 212. Since part of the airflow forms a rotating airflow between the first substrate 211 and the second substrate 212, and the guide holes 214 and the reflux grooves 215 continuously introduce airflow, it is easy to cause the pressure between the first substrate 211 and the second substrate 212 to increase. The overflow holes 216 can discharge excess airflow to avoid excessive pressure affecting the stable operation of the honeycomb spoiler noise reduction component 210. At the same time, the discharged airflow will also merge into the main airflow at a lower speed, further helping to reduce the overall flow rate of the main airflow.

[0042] Furthermore, the guide holes 214, the return grooves 215, the overflow holes 216, and the conical guide tube 213 are arranged in a staggered manner, ensuring that most of the main airflow flows smoothly along the gaps in the conical guide tube 213, while allowing the revolving airflow to evenly interfere with the main airflow, thereby avoiding excessive or insufficient collision of local airflows and preventing the airflow from the overflow holes 216 from forming new turbulence with the main airflow.

[0043] Reference Figure 2 and Figure 5 As shown, the spiral injection deceleration component 220 includes a porous sound absorption and confluence module 240 and a spiral guide switch module 250. The porous sound absorption and confluence module 240 absorbs airflow through its own porous structure to reduce noise. The spiral guide switch module 250 includes a spiral rotating chamber to extend the airflow running distance and direct the airflow toward the kinetic energy turbine conversion component 230.

[0044] Reference Figure 5As shown, the porous sound-absorbing confluence module 240 includes a frame body, a diversion structure, a multi-stage sound-absorbing structure and a deflection structure. The frame body includes an upper frame 2421 and a lower frame 2422. The upper frame 2421 and the lower frame 2422 form a chamber for accommodating the diversion structure and the multi-stage sound-absorbing structure. There are multiple multi-stage sound-absorbing structures, and the multiple multi-stage sound-absorbing structures are circumferentially arranged on the outside of the diversion structure. A central groove and a rectangular through groove 2424 for air flow to enter the diversion structure are provided on the upper frame 2421. The side wall of the lower frame 2422 is provided with multiple side flow ports 2423 corresponding to the multiple diversion structures. The deflection structure is configured as a plurality of deflection plate groups installed at the side flow ports 2423.

[0045] Reference Figure 5 and Figure 6 As shown, the deflector plate group includes a deflector bend 2431, a mounting base plate 2432 for mounting the deflector bend 2431 on the outer wall of the lower frame 2422, and a sound-absorbing cotton 2433 laid on the deflector bend 2431. An airflow channel for airflow deflection is formed between two adjacent deflector bends 2431. The cross-section of the airflow channel is arranged in a trapezoidal structure, and the flared end of the airflow channel faces the spiral guide switch module 250, so that the gas is guided toward the spiral guide switch module 250 in the airflow channel.

[0046] Exemplarily, the diversion structure includes a central base shaft 2442 installed at the center of the lower frame 2422 and a plurality of spiral bends 2441 installed on the central base shaft 2442. The airflow is guided to the side flow port 2423 through the spiral bends 2441 and enters the airflow channel. The surface of the spiral bends 2441 is covered with a layer of sound-absorbing material.

[0047] Exemplarily, the multi-stage sound absorption structure includes a multi-opening mask 2411 installed at a rectangular through groove 2424, and the multi-opening mask 2411 is provided with a plurality of parallel porous sound absorbing panels 2412. The multi-opening mask 2411 is provided with no less than two openings, one opening facing the rectangular through groove 2424, and one opening facing the air flow channel.

[0048] like Figure 6As shown, the spiral guide switch module 250 includes a spiral guide tube 251 with an opening, in which a first annular dividing plate 253 and a second annular dividing plate 254 are installed. The chamber of the spiral guide tube 251 is divided into an outer cavity, a central cavity and an inner cavity by the first annular dividing plate 253 and the second annular dividing plate 254. The second annular dividing plate 254 is also provided with an annular opening communicating with the central cavity and the inner cavity near the opening of the spiral guide tube 251. A spiral dividing piece 252 is spirally provided between the spiral guide tube 251 and the first annular dividing plate. The outer cavity is divided into a spiral rotating chamber by the spiral dividing piece 252, so that the airflow enters the spiral rotating chamber, extending the airflow flow. The stroke of movement, thereby reducing the air flow velocity, completing the third stage of air flow velocity suppression, an annular groove 255 is provided on one side of the first annular dividing cylinder plate 253 close to the bottom of the spiral guide cylinder 251, and the outer cavity and the central cavity are connected through the annular groove 255. The spirally flowing airflow enters the central cavity through the outer cavity and flows back into the inner cavity. A plurality of circumferentially distributed jet tubes 256 are provided at the bottom of the spiral guide cylinder 251. The jet tubes 256 are obliquely arranged at the bottom of the spiral guide cylinder 251, and the air inlet of the spiral guide cylinder 251 faces the chamber surrounded by the second annular dividing plate 254. The airflow in the inner cavity is finally ejected to the kinetic energy turbine conversion component 230 through the jet tube 256.

[0049] Reference Figure 1 、 Figure 2 、 Figure 7 as well as Figure 8 As shown, the kinetic energy turbine conversion component 230 includes a drainage hood, a spiral rotation module and a cutting and diversion module arranged in the drainage hood. The airflow is directed toward the spiral rotation module through the drainage hood to drive the spiral rotation module to rotate about its own axis. The rotating spiral rotation module stirs the drainage hood to integrate the airflow, and the airflow hits the cutting and diversion module to cut the integrated airflow.

[0050] The drainage cover includes an upper loading plate 232 and a lower loading plate 233 that are parallel to each other, and an annular cylinder plate 231 disposed outside the upper loading plate 232 and the lower loading plate 233. A mounting shaft seat 234 is disposed between the upper loading plate 232 and the lower loading plate 233. A plurality of jet slots are formed on the upper loading plate 232, and the jet slots correspond to the jet tubes 256.

[0051] A variable diameter cavity for accommodating the spiral rotation module and the cutting and diverting module is formed in the drainage cover, and the annular cylinder plate 231 is symmetrically formed by two conical annular plates.

[0052] Reference Figure 7 and Figure 8As shown, the spiral rotation module includes a spiral shaft 235 connected to the mounting shaft seat 234 of the upper loading plate 232, and a worm gear 236 arranged on the spiral shaft 235. The cutting and diversion module includes a support column 239 assembled on the mounting shaft seat 234 of the downloading plate 233, a plurality of circumferentially distributed supporting plates 238 installed on the support column 239, and triangular fins 237 distributed on the surface of the supporting plate 238. The support column 239 supports the spiral shaft 235 and is rotatably connected to the spiral shaft 235.

[0053] An active noise reduction structure 300 is also installed at the tail end of the noise reduction duct. It includes a microphone, a controller, and a speaker. The microphone is used to collect the noise signal generated by the exhaust airflow at the tail end of the noise reduction duct in real time and transmit this signal to the controller. The controller has a preset noise cancellation algorithm that analyzes and processes the received noise signal to generate an anti-noise signal with the same frequency and opposite phase as the noise signal. The speaker receives the anti-noise signal output by the controller and plays the anti-noise signal. The anti-noise and the noise generated by the airflow are superimposed and canceled during the transmission process, thereby further reducing the exhaust noise.

[0054] Working Principle: Airflow from the engine exhaust pipe first passes through the main flow inlet 111 of the noise reduction tube and enters the tapered expansion chamber of the inlet section pipe 110. Because the inlet section pipe 110 is a conical cylinder, as the airflow expands within the chamber, its kinetic energy is dispersed within the cavity, resulting in a first stage of velocity reduction.

[0055] Subsequently, the airflow enters the honeycomb turbulence noise reduction component 210. Most of the airflow is guided into the connection area between the honeycomb turbulence noise reduction component 210 and the spiral injection speed reduction component 220 along the tapered guide tubes 213 arrayed on the surfaces of the first substrate 211 and the second substrate 212. The flared end of the tapered guide tube 213 faces the direction of the airflow, so that most of the airflow is regularized and guided by the array-distributed tapered guide tubes 213. Part of the gas passes through the tapered guide holes 214 in the middle of the first substrate 211 and enters the reflux gap between the first substrate 211 and the second substrate 212. It then flows back through the trapezoidal reflux groove 215 on the edge and flows back to the tapered expansion chamber of the inlet section pipe 110, thereby colliding and interfering with the main airflow of the inlet section pipe 110 that enters later. The impact force of the main airflow is weakened by kinetic energy offset, achieving the second stage of flow velocity suppression.

[0056] The airflow processed by the honeycomb turbulence noise reduction assembly 210 enters the spiral jet deceleration assembly 220. It first flows through the porous sound-absorbing confluence module 240, where the central slot and rectangular through-slot 2424 of the upper frame 2421 guide the airflow in. The airflow in the central slot is directed by the spiral bend 2441 of the diversion structure to the side flow port 2423 of the lower frame 2422, and then discharged through the air flow channel of the baffle structure. The airflow in the rectangular through-slot 2424 enters the multi-opening mask 2411 of the multi-stage sound-absorbing structure. After being diverted by the internal porous sound-absorbing panels 2412, it is also directed to the side flow port 2423 of the lower frame 2422, and then merges into the airflow channel through the opening.

[0057] As the airflow passes through the spiral bend 2441, the porous sound-absorbing panel 2412, and the deflection bend 2431, the sound-absorbing material absorbs the vibration noise of the airflow. At the same time, the trapezoidal structure of the airflow channel guides the airflow in a directional manner into the spiral guide switch module 250. The purpose of the porous sound-absorbing confluence module 240 is to rationally divert, guide, and adequately absorb the incoming airflow, thereby reducing airflow noise while ensuring a stable and directional flow state.

[0058] Next, the airflow enters the outer chamber of the spiral rotating chamber of the spiral guide switch module 250. Guided by the spiral partitions 252, it flows along a spiral path, extending the airflow's travel distance and further reducing its velocity, completing the third stage of velocity suppression. The airflow then passes through the annular grooves 255 of the first annular partition plate 253 and enters the central chamber, where it circulates back to the inner chamber. Finally, the airflow in the inner chamber is directed toward the kinetic energy turbine conversion assembly 230 via the inclined jet tube 256 at the bottom of the spiral guide tube 251.

[0059] Airflow passes through the upper carrier plate 232 of the guide housing and enters the variable diameter cavity of the kinetic energy turbine conversion assembly 230. It impacts the worm blade 236 of the spiral self-rotating module, driving the spiral shaft 235 to rotate about its own axis, converting the kinetic energy of the airflow into that of the worm blade 236. The rotating worm blade 236 stirs the airflow within the cavity, integrating it. The integrated airflow then strikes the triangular fins 237 of the cutting and diverting module, breaking it into dispersed streams, further reducing the impact and noise of the airflow.

[0060] Finally, the air is discharged through the pores on the surface of the load plate 233. At this point, the active noise reduction structure 300 at the end of the noise reduction tube is activated. The microphone collects the noise signal of the exhaust air in real time and transmits it to the controller. The controller uses a preset algorithm to generate an anti-noise signal with the same frequency and opposite phase, which is played by the speaker. The anti-noise and exhaust noise are superimposed and offset, ultimately achieving efficient noise reduction.

[0061] The present application realizes efficient noise reduction and stable operation through three processes: multi-stage speed reduction, active and passive coordinated noise reduction, and kinetic energy conversion. The multi-stage step-by-step speed reduction is formed by the conical expansion of the inlet pipe 110, the rectification and backflow interference of the honeycomb turbulence noise reduction component 210, the extended path of the porous sound absorption confluence module 240 of the spiral injection speed reduction component 220, and the spiral guide switch module 250, which gradually reduces the kinetic energy and impact force of the airflow, thereby reducing the noise generation; among them, the porous sound absorption confluence module 240 reduces the airflow vibration noise by diversion and multiple sound absorption, and the kinetic energy vortex is further reduced. The wheel conversion component 230 converts the kinetic energy of the airflow into mechanical kinetic energy, reduces the airflow impact noise, and cooperates with the active noise reduction at the tail end of the noise reduction section pipe 120 to accurately offset the residual noise. The active and passive combination greatly improves the noise reduction effect. In addition, the overflow hole 216 of the honeycomb spoiler noise reduction component 210 is used to balance the pressure, the directional guide of the spiral guide switch module 250, and the airflow integration of the cutting diversion module are used to ensure the stability of the airflow flow and avoid local turbulence to generate secondary noise. While effectively reducing noise, it does not significantly increase the exhaust resistance, taking into account both the noise reduction effect and the smoothness of engine exhaust.

[0062] Finally, a few points should be explained: First, in the description of this application, it should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense, and may refer to mechanical or electrical connections, internal communication between two components, or direct connection. "Up," "down," "left," and "right" are only used to indicate relative positional relationships. When the absolute positions of the objects being described change, the relative positional relationships may also change.

[0063] Secondly: The drawings of the embodiments disclosed in the present invention only involve structures related to the embodiments disclosed in the present invention. Other structures may refer to conventional designs. The same embodiment and different embodiments of the present invention may be combined with each other without conflict.

[0064] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An active and passive noise reduction muffler, which is installed on the engine exhaust pipe, characterized in that: It comprises a noise reduction pipe, wherein the inner cavity of the noise reduction pipe is provided with a honeycomb turbulence noise reduction component (210), a spiral ejection speed reduction component (220), and a kinetic energy turbine conversion component (230) along the airflow direction; The honeycomb turbulence noise reduction component (210) is used to divert and guide the airflow of the engine outlet pipe and perform backflow interference to reduce the main airflow speed; The spiral injection deceleration component (220) comprises a porous sound absorption and confluence module (240) and a spiral flow guide switch module (250), wherein the porous sound absorption and confluence module (240) absorbs airflow through its own porous structure to reduce noise, and the spiral flow guide switch module (250) comprises a spiral rotation chamber to extend the airflow running stroke and direct the airflow toward the kinetic energy turbine conversion component (230); A kinetic energy turbine conversion assembly (230) comprises a flow guide hood, a spiral rotation module and a cutting and diverting module arranged in the flow guide hood, wherein the airflow is directed toward the spiral rotation module through the flow guide hood to drive the spiral rotation module to rotate about its own axis, the rotating spiral rotation module stirs the flow guide hood to integrate the airflow, and the airflow impacts the cutting and diverting module to cut the integrated airflow.

2. The active and passive noise reduction muffler according to claim 1, characterized in that: The honeycomb disturbance noise reduction component (210) comprises a first substrate (211) and a second substrate (212) which are parallel to each other, a reflux gap being formed between the first substrate (211) and the second substrate (212), a plurality of conical guide tubes (213) being arranged in a through-type array on the surfaces of the first substrate (211) and the second substrate (212), a plurality of guide holes (214) being provided in a central region of the first substrate (211), a reflux groove (215) being provided in an edge region thereof, and an overflow hole (216) being provided on the surface of the second substrate (212).

3. The active and passive noise reduction muffler according to claim 2, characterized in that: The guide hole (214) is a tapered hole, the expanded end of which faces the direction of the airflow; the cross-section of the return groove (215) is arranged in a trapezoidal structure, the contracted end of the return groove (215) faces the direction of the airflow; and the guide hole (214), the return groove (215) and the overflow hole (216) are arranged in a staggered manner with the tapered guide tube (213).

4. The active and passive noise reduction muffler according to claim 3, characterized in that: The porous sound absorption confluence module (240) comprises a frame body, a diversion structure, a multi-stage sound absorption structure and a deflection structure, the frame body comprises an upper frame body (2421) and a lower frame body (2422), the upper frame body (2421) and the lower frame body (2422) form a chamber for accommodating the diversion structure and the multi-stage sound absorption structure, the number of the multi-stage sound absorption structures is multiple, and the multiple multi-stage sound absorption structures are circumferentially arranged on the outside of the diversion structure, the upper frame body (2421) is provided with a central groove and a rectangular through groove (2424) for air flow to enter the diversion structure, the side wall of the lower frame body (2422) is provided with a plurality of side flow ports (2423) corresponding to the plurality of diversion structures, and the deflection structure is configured as a plurality of deflection plate groups installed at the side flow ports (2423).

5. The active and passive noise reduction muffler according to claim 4, characterized in that: The deflector plate group includes a deflector bend (2431), a mounting base plate (2432) for mounting the deflector bend (2431) on the outer wall of the lower frame (2422), and sound-absorbing cotton (2433) laid on the deflector bend (2431). An airflow channel for guiding airflow is formed between two adjacent deflector bends (2431). The cross-section of the airflow channel is arranged in a trapezoidal structure, and the flared end of the airflow channel faces the spiral guide switch module (250), so that the gas in the airflow channel is guided toward the spiral guide switch module (250).

6. The active and passive noise reduction muffler according to claim 5, characterized in that: The diversion structure includes a central base shaft (2442) installed at the center of the lower frame (2422) and a plurality of spiral bends (2441) installed on the central base shaft (2442). The airflow is guided to the side flow port (2423) and enters the airflow channel via the spiral bends (2441). The surface of the spiral bends (2441) is covered with a layer of sound-absorbing material.

7. The active and passive noise reduction muffler according to claim 6, characterized in that: The multi-stage sound absorption structure comprises a multi-opening mask (2411) installed at a rectangular through slot (2424), wherein the multi-opening mask (2411) is provided with a plurality of parallel porous sound absorption panels (2412), and the multi-opening mask (2411) is provided with no less than two openings, one of the openings facing the rectangular through slot (2424), and the other opening facing the air flow channel.

8. The active and passive noise reduction muffler according to claim 7, characterized in that: The spiral guide switching module (250) comprises a spiral guide tube (251) with an opening, in which a first annular partitioning plate (253) and a second annular partitioning plate (254) are installed. A spiral partitioning piece (252) is spirally arranged between the spiral guide tube (251) and the first annular partitioning plate. An annular through groove (255) is provided on one side of the first annular partitioning plate (253) close to the bottom of the spiral guide tube (251). A plurality of circumferentially distributed jet tubes (256) are provided at the bottom of the spiral guide tube (251). The jet tubes (256) are obliquely arranged at the bottom of the spiral guide tube (251). The air inlet of the spiral guide tube (251) faces the chamber surrounded by the second annular partitioning plate (254).

9. The active and passive noise reduction muffler according to claim 8, characterized in that: The drainage cover comprises an upper loading plate (232), a lower loading plate (233) and an annular cylinder plate (231) arranged outside the upper loading plate (232) and the lower loading plate (233), wherein a mounting shaft seat (234) is arranged between the upper loading plate (232) and the lower loading plate (233), and a plurality of jet grooves are provided on the upper loading plate (232), and the jet grooves correspond to the jet cylinder (256); A variable diameter cavity for accommodating the spiral rotation module and the cutting and diverting module is formed in the drainage cover, and the annular cylinder plate (231) is symmetrically formed by two conical annular plates.

10. The active and passive noise reduction muffler according to claim 9, characterized in that: The spiral rotation module includes a spiral shaft (235) connected to the mounting shaft seat (234) of the upper loading plate (232) by a bearing, and a worm (236) arranged on the spiral shaft (235). The cutting and diversion module includes a support column (239) assembled on the mounting shaft seat (234) of the downloading plate (233), a plurality of circumferentially distributed supporting plates (238) installed on the support column (239), and triangular fins (237) distributed on the surface of the supporting plates (238).

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