Broadband reactive muffler, engine exhaust system and general gasoline engine

Abstract

The utility model discloses a broadband reactive muffler, an engine exhaust system and a general gasoline engine, the broadband reactive muffler comprises a muffler shell with an expansion cavity and a Helmholtz resonance muffling piece arranged in the muffler shell, an inner partition plate is arranged in the muffler shell in the radial direction, and the inner partition plate is arranged in the muffler shell in the radial direction; the expansion chamber is divided into a first chamber and a second chamber by the inner partition plate, a mounting through hole is formed in the middle of the inner partition plate, and the Helmholtz resonance silencing part is mounted in the mounting through hole; the two ends of the Helmholtz resonance silencing part are embedded into the first cavity and the second cavity correspondingly, and the first cavity and the second cavity are communicated through the Helmholtz resonance silencing part. On the premise of ensuring that the mounting space of the silencer is not increased and no sound-absorbing cotton is arranged, the silencing frequency range of the reactive silencer is effectively expanded.

Description

Technical Field

[0001] The present application belongs to the technical field of mufflers, and in particular relates to a broadband resistive muffler, an engine exhaust system and a general-purpose engine. Background Art

[0002] In modern society, science and technology are advancing rapidly, with numerous inventions and discoveries emerging one after another, and people's living standards are constantly improving. While people continue to enjoy the modern material civilization brought about by advanced technology, they also have to endure the environmental pollution it brings. Among these pollutions, noise pollution is the most serious and has the widest impact. At the very least, noise pollution affects normal human production and life, and at the worst, it endangers human health.

[0003] For general-purpose mufflers, under the premise of ensuring that the installation space of the muffler does not increase and no sound-absorbing cotton is installed, in order to find a method to maximize the muffler's sound attenuation and improve its frequency characteristics so that it can better eliminate the noise of the intake system, designing a muffler internal structure with excellent performance is an effective measure to reduce the noise of the intake and exhaust systems.

[0004] Resistant mufflers perform well in the low and medium frequency range (below 2000Hz), so they are often used in general engine mufflers. Figure 1 As shown, a reactive muffler uses internal components such as pipes and baffles to create various muffler units, such as expansion chambers and resonance chambers. This reduces sound waves by reflecting and interfering with them due to structural changes during sound wave transmission, such as sudden changes in cross-section or connecting resonance chambers. Existing reactive mufflers have poor performance in reducing high-frequency noise. If high-frequency noise needs to be reduced, this is usually achieved by adding sound-absorbing cotton inside the reactive muffler.

[0005] Therefore, how to effectively expand the noise reduction frequency range of the resistance muffler without increasing the installation space of the muffler and without installing sound-absorbing cotton is a problem that needs to be solved urgently in this field. Utility Model Content

[0006] In response to the defects in the existing technology, the purpose of this application is to provide a wide-band resistant silencer, an engine exhaust system and a general-purpose engine, which can effectively expand the sound-absorbing frequency range of the resistant silencer while ensuring that the installation space of the silencer is not increased and no sound-absorbing cotton is provided.

[0007] In order to achieve the above objectives, this application provides the following solutions:

[0008] According to a first aspect of the present application, a broadband reactive muffler is provided, comprising a muffler housing having an expansion chamber and a Helmholtz resonance muffler disposed in the muffler housing, wherein:

[0009] An inner partition is radially arranged in the muffler shell, and the inner partition divides the expansion chamber into a first chamber and a second chamber. A mounting hole is opened in the middle of the inner partition, and the Helmholtz resonance silencer is installed in the mounting hole. The two ends of the Helmholtz resonance silencer are respectively embedded in the first chamber and the second chamber to connect the first chamber and the second chamber.

[0010] Preferably, the Helmholtz resonance muffler comprises a cylindrical inner tube and a trumpet-shaped vent pipe, and the vent pipe is used to connect the first chamber and the second chamber;

[0011] The air inlet end of the inner tube is provided with a first baffle, and the air outlet end of the inner tube is provided with a second baffle. The first baffle and the second baffle are both sealed and connected to the inner tube. The first baffle, the inner tube and the second baffle form a resonance chamber. The ventilation pipe passes through the first baffle and the second baffle, and the outer wall of the ventilation pipe is sealed and connected to the first baffle and the second baffle.

[0012] The diameter of the air inlet end of the vent pipe is larger than the diameter of the air outlet end thereof, and a first vent hole is provided on the wall of the portion of the vent pipe located in the resonance chamber, and the first vent hole is used to connect the resonance chamber and the internal air flow channel of the vent pipe.

[0013] Preferably, a plurality of the first ventilation holes are provided, and the plurality of the first ventilation holes are evenly distributed on the wall of the ventilation pipe.

[0014] Preferably, the air inlet end of the vent pipe is arranged to protrude toward the air inlet side relative to the first baffle, and the air outlet end of the vent pipe is arranged to protrude toward the air outlet side relative to the second baffle.

[0015] Preferably, the Helmholtz resonance muffler further includes a muffler baffle, which is arranged at the air inlet end of the vent pipe, and a second vent hole is opened on the muffler baffle, and the second vent hole is used to connect the first chamber and the internal air flow channel of the vent pipe.

[0016] Preferably, a plurality of the first vent holes are provided, and the plurality of the second vent holes are evenly distributed on the sound-absorbing baffle.

[0017] Preferably, the Helmholtz resonance muffler further includes an intermediate baffle, which is disposed between the first baffle and the second baffle, wherein the outer edge of the intermediate baffle is sealedly connected to the inner wall of the inner tube, and the vent pipe also passes through the intermediate baffle, and the outer wall of the vent pipe is sealedly connected to the intermediate baffle.

[0018] The middle baffle divides the resonance chamber into a first resonance chamber and a second resonance chamber. Both the first resonance chamber and the second resonance chamber are connected to the internal air flow channel of the ventilation pipe through the first ventilation hole.

[0019] Preferably, the muffler shell includes an outer tube, an air intake connecting tube, an air outlet connecting tube, a first outer sealing plate and a second outer sealing plate, the air intake connecting tube and the air outlet connecting tube have the same diameter and are both smaller than the diameter of the outer tube, one end of the outer tube is connected to the air intake connecting tube through the first outer sealing plate, and the other end of the outer tube is connected to the air outlet connecting tube through the second outer sealing plate, and the first outer sealing plate, the outer tube and the second outer sealing plate enclose the expansion chamber.

[0020] According to a second aspect of the present application, the present application provides an engine exhaust system, comprising the broadband resistive muffler described in any one of the above-mentioned first aspects.

[0021] According to the third aspect of the present application, the present application provides a general engine, including the engine exhaust system described in the second aspect above.

[0022] Due to the adoption of the above technical solution, this application has the following beneficial effects:

[0023] Based on the existing technology, the present application provides an inner partition radially inside a silencer shell having an expansion chamber, the expansion chamber is divided into a first chamber and a second chamber by the inner partition, and a mounting hole is opened in the middle of the inner partition, a Helmholtz resonance silencer is installed in the mounting hole, and the two ends of the Helmholtz resonance silencer are respectively embedded in the first chamber and the second chamber and connected to the first chamber and the second chamber, thereby effectively expanding the silencer frequency range of the resistive silencer without increasing the installation space of the silencer and without providing sound-absorbing cotton.

[0024] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific embodiments of this application or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the various elements or parts are not necessarily drawn according to the actual scale. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without inventive effort.

[0026] Figure 1This is a schematic diagram of the cross-sectional structure of an existing general-purpose muffler;

[0027] Figure 2 2. It is a schematic diagram of the three-dimensional structure of a broadband reactive muffler in one embodiment of the present application;

[0028] Figure 3 yes Figure 2 The main view;

[0029] Figure 4 yes Figure 3 AA cross-sectional view;

[0030] Figure 5 yes Figure 2 A three-dimensional cross-sectional view of

[0031] Figure 6 yes Figure 5 The broadband reactive muffler in the embodiment of the present application is shown with Figure 1 The comparative diagram of the outlet response characteristic curve of the existing general-purpose muffler shown;

[0032] Figure 7 yes Figure 5 The broadband reactive muffler in the embodiment of the present application is shown with Figure 1 The figure shows a comparison of transmission loss characteristic curves of conventional mufflers. DETAILED DESCRIPTION

[0033] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0034] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art in the art to which this application belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with their meanings in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless specifically defined.

[0035] In this application, the terms "first," "second," etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the quantity of the technical features indicated. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0036] Furthermore, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," and the like should be interpreted broadly. For example, they may refer to fixed or detachable connections, or integration; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0037] like Figure 2-5 As shown, the embodiment of the present application provides a broadband reactive muffler, comprising a muffler housing 2 having an expansion chamber 1 and a Helmholtz resonance muffler 3 disposed in the muffler housing 2, wherein:

[0038] An inner partition 4 is radially arranged in the muffler shell 2, and the inner partition 4 divides the expansion chamber 1 into a first chamber 11 and a second chamber 12. A mounting hole 41 is opened in the middle of the inner partition 4, and the Helmholtz resonance muffler 3 is installed in the mounting hole 41. The two ends of the Helmholtz resonance muffler 3 are respectively embedded in the first chamber 11 and the second chamber 12 and connect the first chamber 11 and the second chamber 12.

[0039] The broadband resistant silencer of the embodiment of the present application is provided with an inner partition 4 radially inside a silencer shell 2 having an expansion chamber 1, and the expansion chamber 1 is divided into a first chamber 11 and a second chamber 12 by the inner partition 4. A mounting hole 41 is provided in the middle of the inner partition 4, and a Helmholtz resonance silencer 3 is installed in the mounting hole 41. The two ends of the Helmholtz resonance silencer 3 are respectively embedded in the first chamber 11 and the second chamber 12 and connect the first chamber 11 and the second chamber 12, thereby effectively expanding the sound absorption frequency range of the resistant silencer without increasing the installation space of the silencer and without providing sound-absorbing cotton.

[0040] In one embodiment, the Helmholtz resonance muffler 3 includes a cylindrical inner tube 31 and a trumpet-shaped vent pipe 32, and the vent pipe 32 is used to connect the first chamber 11 and the second chamber 12;

[0041] The air inlet end of the inner tube 31 is provided with a first baffle 33, and the air outlet end of the inner tube 31 is provided with a second baffle 34. The first baffle 33 and the second baffle 34 are both sealed and connected to the inner tube 31. The first baffle 33, the inner tube 31 and the second baffle 34 form a resonance chamber 35. The vent pipe 32 passes through the first baffle 33 and the second baffle 34, and the outer wall of the vent pipe 32 is sealed and connected to the first baffle 33 and the second baffle 34.

[0042] The diameter of the air inlet end of the vent pipe 32 is larger than the diameter of the air outlet end thereof. A first vent hole 321 is provided on the wall of the portion of the vent pipe 32 located within the resonance chamber 35 . The first vent hole 321 is used to connect the internal air flow channel of the resonance chamber 35 and the vent pipe 32 .

[0043] The Helmholtz resonance muffler 3 in this embodiment is provided with a cylindrical inner tube 31, and a first baffle 33 and a second baffle 34 are provided at both ends of the inner tube 31, so that the first baffle 33, the inner tube 31 and the second baffle 34 form a resonance chamber 35, and at the same time, a trumpet-shaped vent pipe 32 is provided inside the inner tube 31, and the diameter of the air inlet end of the vent pipe 32 is larger than the diameter of the air outlet end thereof, and a first vent hole 321 is provided on the wall of the portion of the vent pipe 32 located in the resonance chamber 35, and the internal air flow channel of the resonance chamber 35 and the vent pipe 32 is connected through the first vent hole 321, so that the air flow in the first chamber 11 enters the first chamber 11 from the air inlet end of the vent pipe 32. , enters the resonance chamber 35 through the closed first vent hole 321 on the vent pipe 32, and then is reflected and enters the vent pipe 32 through the first vent hole 321 and is discharged to the second chamber 12 from the outlet end of the vent pipe 32. The sound reaches the resonance frequency in the resonance chamber 35, thereby realizing the conversion from sound energy to kinetic energy, achieving the sound elimination effect and realizing the noise elimination based on the Helmholtz resonance principle. Experiments have shown that this structure can effectively increase the sound elimination frequency width range, so that the silencer has better sound elimination effect in both low frequency and high frequency bands, breaking through the technical bottleneck of the traditional method of reducing high-frequency noise by only adding sound-absorbing cotton, thereby reducing the cost investment of the silencer.

[0044] It should be noted that controlling the air penetration rate and the aperture size and number of the first vent holes 321 can adjust the inlet flow rate and impedance. The air penetration rate and the aperture size of the first vent holes 321 on the ventilation tube 32 in this embodiment can be set through experiments according to the frequency range of the noise to be eliminated.

[0045] In one embodiment, a plurality of first vent holes 321 are provided, and the plurality of first vent holes 321 are evenly distributed on the wall of the vent pipe 32. This arrangement allows the airflow to be evenly diffused when entering the resonance chamber 35 from the vent pipe 32, thereby better reducing the noise loudness.

[0046] In one embodiment, the air inlet end of the vent pipe 32 is convexly arranged toward the air inlet side relative to the first baffle 33 , and the air outlet end of the vent pipe 32 is convexly arranged toward the air outlet side relative to the second baffle 34 .

[0047] In one embodiment, the Helmholtz resonance muffler 3 further includes a muffler baffle 36, which is disposed at the air inlet end of the vent pipe 32. A second vent hole 361 is provided on the muffler baffle 36, and the second vent hole 361 is used to connect the first chamber 11 and the internal air flow channel of the vent pipe 32. By disposing the muffler baffle 36 at the air inlet end of the vent pipe 32 and providing the second vent hole 361 on the muffler baffle 36, when the air flow enters the interior of the vent pipe 32 from the first chamber 11 through the air inlet end of the vent pipe 32, the air flow impedance can be increased by the muffler baffle 36, thereby improving the muffler effect.

[0048] It should be noted that controlling the air penetration rate and the aperture size and number of the second air holes 361 can adjust the inlet flow rate and impedance. The air penetration rate and the aperture size of the second air holes 361 on the ventilation tube 32 in this embodiment can be set through experiments according to the frequency range of the noise to be eliminated.

[0049] In one embodiment, a plurality of first vent holes 321 are provided, and a plurality of second vent holes 361 are evenly distributed on the muffler baffle 36. This arrangement allows the airflow to diffuse evenly when entering the resonance chamber 35 from the vent pipe 32, thereby better reducing the noise loudness.

[0050] In one embodiment, the Helmholtz resonance muffler 3 further includes an intermediate baffle 37, which is disposed between the first baffle 33 and the second baffle 34. The outer edge of the intermediate baffle 37 is sealed with the inner wall of the inner tube 31. The vent pipe 32 also passes through the intermediate baffle 37, and the outer wall of the vent pipe 32 is sealed with the intermediate baffle 37.

[0051] The middle baffle 37 divides the resonance chamber 35 into a first resonance chamber 351 and a second resonance chamber 352 . The first resonance chamber 351 and the second resonance chamber 352 are both connected to the internal air flow channel of the ventilation pipe 32 through the first ventilation hole 321 .

[0052] In this embodiment, the resonance chamber 35 is divided into two resonance chambers by the middle baffle 37, which increases the number of resonance chambers, thereby increasing the sound elimination frequency and the sound elimination amount to a certain extent.

[0053] Since controlling the number of resonance chambers can adjust the silencing frequency and the silencing amount, the number of resonance chambers can be set according to the frequency range of the noise that needs to be eliminated through experiments.

[0054] In one embodiment, the muffler housing 2 includes an outer tube 21, an air intake connecting tube 22, an air outlet connecting tube 23, a first outer sealing plate 24 and a second outer sealing plate 25. The diameters of the air intake connecting tube 22 and the air outlet connecting tube 23 are the same and are both smaller than the diameter of the outer tube 21. One end of the outer tube 21 is connected to the air intake connecting tube 22 through the first outer sealing plate 24, and the other end of the outer tube 21 is connected to the air outlet connecting tube 23 through the second outer sealing plate 25. The first outer sealing plate 24, the outer tube 21 and the second outer sealing plate 25 form an expansion chamber 1.

[0055] like Figure 6-Figure 7 As shown, Figure 6 yes Figure 5 The broadband reactive muffler in the embodiment of the present application is shown with Figure 1 The comparison diagram of the outlet response characteristic curve of the existing general machine muffler is shown in the figure. Figure 7 yes Figure 5 The broadband reactive muffler in the embodiment of the present application is shown with Figure 1 The figure shows a comparison of transmission loss characteristic curves of conventional mufflers.

[0056] By comparison Figure 6 The blue curve in ( Figure 1 The outlet response characteristic curve of the existing general-purpose muffler shown) and the orange curve ( Figure 5 It can be seen from the outlet response characteristic curve of the wide-band resistive silencer in the embodiment of the present application that the wide-band resistive silencer in the embodiment of the present application increases the width range of the sound-absorbing frequency, has better sound-absorbing effects in both low and high frequency bands, effectively reduces the outlet response of the low and high frequency bands, especially the sound-absorbing effect of the high frequency band, and breaks through the technical bottleneck that the traditional silencer can only achieve by adding sound-absorbing cotton inside the resistive silencer, thereby effectively reducing the cost investment of the silencer.

[0057] By comparison Figure 7 The blue curve in ( Figure 1 The transmission loss characteristic curve of the conventional muffler shown) and the orange curve ( Figure 5 From the transmission loss characteristic curve of the broadband resistive silencer in the embodiment of the present application shown in FIG, it can be seen that the transmission loss of the broadband resistive silencer in the embodiment of the present application is more balanced and stable, which shows that the broadband resistive silencer in the embodiment of the present application can effectively reduce the loudness and sharpness of the silencer and improve the sound quality of the silencer.

[0058] An embodiment of the present application also provides an engine exhaust system, comprising the broadband reactive muffler of any of the above embodiments.

[0059] It should be noted that, since the engine exhaust system includes the broadband reactive muffler of any of the above-mentioned embodiments, the engine exhaust system has the same technical effects as the broadband reactive mufflers of the above-mentioned embodiments. The specific structure of the engine exhaust system belongs to the prior art and will not be described in detail here.

[0060] An embodiment of the present application also provides a general engine, including the engine exhaust system in the above embodiment.

[0061] It should be noted that, since the engine exhaust system includes the engine exhaust system in the above embodiment, the general engine has the same technical effects as the engine exhaust system in the above embodiment. The specific structure of the general engine belongs to the prior art and will not be described here.

[0062] Those skilled in the art will appreciate that although some embodiments herein include certain features included in other embodiments but not other features, the combination of features from different embodiments is intended to be within the scope of this application and to form different embodiments. In some instances, well-known methods, structures, and techniques are not shown in detail in order not to obscure the understanding of this specification.

[0063] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and description of the present application.

Claims

1. A broadband reactive muffler, characterized in that: The invention comprises a muffler shell having an expansion chamber and a Helmholtz resonance muffler arranged in the muffler shell, wherein: An inner partition is radially arranged in the muffler shell, and the inner partition divides the expansion chamber into a first chamber and a second chamber. A mounting hole is opened in the middle of the inner partition, and the Helmholtz resonance silencer is installed in the mounting hole. The two ends of the Helmholtz resonance silencer are respectively embedded in the first chamber and the second chamber to connect the first chamber and the second chamber.

2. The broadband reactive muffler according to claim 1, characterized in that: The Helmholtz resonance muffler includes a cylindrical inner tube and a trumpet-shaped vent pipe, and the vent pipe is used to connect the first chamber and the second chamber; The air inlet end of the inner tube is provided with a first baffle, and the air outlet end of the inner tube is provided with a second baffle. The first baffle and the second baffle are both sealed and connected to the inner tube. The first baffle, the inner tube and the second baffle form a resonance chamber. The ventilation pipe passes through the first baffle and the second baffle, and the outer wall of the ventilation pipe is sealed and connected to the first baffle and the second baffle. The diameter of the air inlet end of the vent pipe is larger than the diameter of the air outlet end thereof, and a first vent hole is provided on the wall of the portion of the vent pipe located in the resonance chamber, and the first vent hole is used to connect the resonance chamber and the internal air flow channel of the vent pipe.

3. The broadband reactive muffler according to claim 2, characterized in that: There are multiple first ventilation holes, and the multiple first ventilation holes are evenly distributed on the tube wall of the ventilation tube.

4. The broadband reactive muffler according to claim 2, characterized in that: The air inlet end of the vent pipe is arranged to protrude toward the air inlet side relative to the first baffle, and the air outlet end of the vent pipe is arranged to protrude toward the air outlet side relative to the second baffle.

5. The broadband reactive muffler according to claim 4, characterized in that: The Helmholtz resonance muffler also includes a muffler baffle, which is arranged at the air inlet end of the vent pipe. A second vent hole is opened on the muffler baffle, and the second vent hole is used to connect the first chamber and the internal air flow channel of the vent pipe.

6. The broadband reactive muffler according to claim 5, characterized in that: There are a plurality of first vent holes, and a plurality of second vent holes are evenly distributed on the sound-absorbing baffle.

7. The broadband reactive muffler according to claim 2, characterized in that: The Helmholtz resonance muffler also includes an intermediate baffle, which is arranged between the first baffle and the second baffle. The outer edge of the intermediate baffle is sealed with the inner wall of the inner tube. The vent pipe also passes through the intermediate baffle, and the outer wall of the vent pipe is sealed with the intermediate baffle. The middle baffle divides the resonance chamber into a first resonance chamber and a second resonance chamber. Both the first resonance chamber and the second resonance chamber are connected to the internal air flow channel of the ventilation pipe through the first ventilation hole.

8. The broadband reactive muffler according to any one of claims 1 to 7, characterized in that: The muffler shell includes an outer tube, an air intake connecting tube, an air outlet connecting tube, a first outer sealing plate and a second outer sealing plate. The diameters of the air intake connecting tube and the air outlet connecting tube are the same and are both smaller than the diameter of the outer tube. One end of the outer tube is connected to the air intake connecting tube through the first outer sealing plate, and the other end of the outer tube is connected to the air outlet connecting tube through the second outer sealing plate. The first outer sealing plate, the outer tube and the second outer sealing plate enclose the expansion chamber.

9. An engine exhaust system, characterized in that: The invention comprises the broadband reactive muffler according to any one of claims 1 to 8.

10. A general engine, characterized in that: Includes the engine exhaust system as claimed in claim 9.

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