Sectional type silencer and motorcycle

Abstract

According to the sectional type silencer and the motorcycle, an inner cylinder body and an outer cylinder body are at least partially installed in an interference fit mode, the inner cylinder body and the outer cylinder body are designed in a sectional mode, compared with a conventional integral type inner cylinder body structure, the overall length of the inner cylinder body is shortened, the expansion amount of thermal expansion and cold contraction of the inner cylinder body is reduced, and the service life of the inner cylinder body is prolonged. The problem that the inner cylinder body is broken due to thermal expansion and cold contraction is solved, the risk of tension fracture at the connecting position of the inner cylinder body and the rear oxygen sensor is reduced, and the stability of the silencer is improved; the catalytic converter is arranged at the front position of the front section of the inner barrel and fixed through welding, so that the supporting strength of the catalytic converter is improved, the conversion efficiency of the catalytic converter is improved, the use cost is reduced, and the goal of green emission is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of motorcycle engines, and particularly to a segmented muffler and a motorcycle. Background Art

[0002] A muffler is an important component of an engine. It is used to reduce the noise generated by the engine and convert the harmful components in the exhaust gas emitted by the engine into carbon dioxide and nitrogen, thereby improving the comfort of equipment use and reducing environmental pollution. Consumers' requirements for the quality of mufflers and the emission requirements of engines are constantly increasing, which has promoted the development of muffler structure technology.

[0003] Compared with traditional mufflers, existing mufflers usually adopt the impedance composite sound absorption principle, which combines the characteristics of reactive mufflers and resistive mufflers, has a wider frequency range of noise reduction ability and better environmental adaptability, can achieve high-efficiency noise reduction in a wider frequency range, and create a quieter driving environment. However, there are also many deficiencies. For example, both ends of the inner cylinder are fixed by welding, and due to thermal expansion and contraction, the inner cylinder changes in length repeatedly for a long time, and the change frequency is relatively large, resulting in the rupture of the inner cylinder; due to the different degrees of thermal expansion and contraction of the inner cylinder, outer cylinder and the conduit of the catalytic converter, there is a risk of tearing at the welding position between the inner cylinder of the muffler and the post-oxygen sensor; the catalytic converter is fixedly installed in the inner cylinder through a partition, which cannot provide sufficient support strength, and the catalytic converter is far from the engine exhaust port, and the ignition temperature is insufficient, resulting in a low conversion efficiency of the catalytic converter and affecting emissions.

[0004] Therefore, it is necessary to improve the structure of the existing muffler, which can not only avoid the rupture problem of the inner cylinder of the muffler caused by thermal expansion and contraction, solve the risk of tearing at the connection position between the inner cylinder of the muffler and the post-oxygen sensor, but also optimize the installation position of the catalytic converter, which can not only increase the support strength of the catalytic converter, improve the stability of the device, but also improve the conversion efficiency of the catalytic converter, reduce the use cost, and achieve the goal of green emissions. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a segmented muffler and a motorcycle, which can not only avoid the rupture problem of the inner cylinder of the muffler caused by thermal expansion and contraction, solve the risk of tearing at the connection position between the inner cylinder of the muffler and the post-oxygen sensor, but also optimize the installation position of the catalytic converter, which can not only increase the support strength of the catalytic converter, improve the stability of the device, but also improve the conversion efficiency of the catalytic converter, reduce the use cost, and achieve the goal of green emissions.

[0006] To achieve the object of the invention, a segmented muffler provided by the invention includes an outer cylinder and an inner cylinder. The inner cylinder includes a front section of the inner cylinder and a rear section of the inner cylinder. At least one end of the rear section of the inner cylinder is in interference fit with the outer cylinder.

[0007] Furthermore, the interference fit and the fixed connection between the rear section of the inner cylinder and the outer cylinder are realized through a smooth curve transition section. The smooth curve transition section is a smooth curve transition intermediate member or / and formed by the deformation of the inner cylinder itself.

[0008] Furthermore, an interference fit is realized between the rear end of the rear section of the inner cylinder and the outer cylinder through a smooth curve transition intermediate member I, and the front end is fixedly welded to the outer cylinder through a smooth curve transition intermediate member II.

[0009] Furthermore, the rear end of the front section of the inner cylinder is welded to the outer cylinder through its own smooth curve transition section, and the front end is welded to the outer cylinder through gradual necking.

[0010] Furthermore, the outer cylinder includes a front section of the outer cylinder and a rear section of the outer cylinder. The front end of the rear section of the outer cylinder is butted and welded to the rear end of the front section of the inner cylinder.

[0011] Furthermore, the smooth curve transition intermediate member II is a reduced-diameter cylindrical structure II. The large-diameter section of the reduced-diameter cylindrical structure II covers forward the butting position of the front end of the rear section of the outer cylinder and the rear end of the front section of the inner cylinder and is fixedly welded, and the small-diameter section extends backward to the inner circle of the front end of the rear section of the inner cylinder and is fixedly welded;

[0012] The smooth curve transition intermediate member I is a reduced-diameter cylindrical structure I. The small-diameter section of the reduced-diameter cylindrical structure I extends backward and is sleeved outside the rear section of the inner cylinder and is fixedly welded, and the large-diameter section is in interference fit with the rear section of the outer cylinder; or the small-diameter section of the reduced-diameter cylindrical structure I extends backward and is sleeved outside the rear section of the inner cylinder and is in interference fit, and the large-diameter section is fixedly welded to the rear section of the outer cylinder.

[0013] Furthermore, the rear end of the front section of the outer cylinder is sleeved outside the rear end of the front section of the inner cylinder and is fixedly welded, and the front section of the outer cylinder and the rear section of the outer cylinder are transitioned and fixedly welded through an expansion joint.

[0014] Furthermore, a catalytic converter is further included. The catalytic converter is located at a position close to the front of the front section of the inner cylinder;

[0015] The front section of the inner cylinder and the front section of the outer cylinder are partially closely arranged against the catalytic converter, and a corresponding resonance cavity is formed on the corresponding side.

[0016] Furthermore, the inner cylinder is divided into a plurality of resonance cavities by a plurality of partition plates. A plurality of exhaust pipes, intake pipes and resonance pipes are correspondingly supported on the partition plates. The exhaust pipes, intake pipes and resonance pipes are supported on the corresponding partition plates through interference fit.

[0017] The motorcycle of the present invention includes the segmented muffler described above.

[0018] Advantages of the present invention: For the segmented muffler and motorcycle of the present invention, at least part of the installation between the inner cylinder and the outer cylinder adopts an interference fit method, and the inner cylinder and the outer cylinder are designed in a segmented manner. Compared with the conventional integral inner cylinder structure, the overall length of the inner cylinder is shortened, the expansion and contraction amount caused by thermal expansion and contraction of the inner cylinder is reduced, the problem of cracking of the inner cylinder caused by thermal expansion and contraction is solved, and the risk of tearing at the connection position between the inner cylinder and the post-oxygen sensor is also reduced, improving the stability of the muffler; the catalytic converter is arranged at a position close to the front of the front section of the inner cylinder and fixed by welding, increasing the support strength of the catalytic converter, improving the conversion efficiency of the catalytic converter, reducing the use cost, and achieving the goal of green emissions. Description of the Drawings

[0019] Figure 1 is the longitudinal sectional view of the segmented muffler of the present invention along the length direction;

[0020] Figure 2 is Figure 1 the enlarged view of part A in

[0021] Figure 3 is Figure 1 the enlarged view of part B in

[0022] Figure 4 is Figure 1 the enlarged view of part C in

[0023] Figure 5 is Figure 1 the longitudinal sectional view along part D in

[0024] Figure 6 is the structural schematic diagram of the muffler.

[0025] Description of the reference numerals: 1. Outer cylinder; 101. Front section of the outer cylinder; 1011. Expansion joint on the front section of the outer cylinder; 102. Rear section of the outer cylinder; 2. Inner cylinder; 201. Front section of the inner cylinder; 2011. Smooth curve transition section of the front section of the inner cylinder itself; 2012. Expansion joint on the front section of the inner cylinder; 202. Rear section of the inner cylinder; 3. Smooth curve transition intermediate member; 301. Smooth curve transition intermediate member I; 302. Smooth curve transition intermediate member II; 4. Expansion joint; 5. Catalytic converter; 6. Baffle; 7. Exhaust pipe; 8. Post-oxygen sensor; 9. Intake pipe; 10. Resonator pipe. Detailed Description of the Invention

[0026] The following further describes the present invention in detail with reference to the attached Figure 1-6 drawings.

[0027] An embodiment of the present invention discloses a segmented muffler, which includes an outer cylinder 1 and an inner cylinder 2. The inner cylinder 2 includes a front section 201 and a rear section 202 of the inner cylinder. At least one end of the rear section 202 of the inner cylinder is in interference fit with the outer cylinder 1. The outer cylinder 1 functions to protect and seal, preventing the leakage of engine exhaust gas and providing support and fixation for the inner cylinder 2. The material of the outer cylinder 1 generally has good strength and corrosion resistance to withstand the pressure inside the muffler and the erosion of the external environment. The inner cylinder 2 is the core noise reduction component of the muffler and usually adopts a perforated design, enabling the exhaust gas to evenly enter each chamber inside the inner cylinder 2. At the same time, sound-absorbing materials such as fiberglass or ceramic fiber can be filled between the outer cylinder 1 and the inner cylinder 2. Through the absorption of sound waves by the sound-absorbing materials, the noise is further reduced. Interference fit refers to a fitting method in which the enclosed part, such as a shaft, is inserted into the enclosing part, such as a hole. After assembly, the actual interference amount between the two is within the specified range, so that the two parts are tightly connected together, and a kind of assembly method that relies on the frictional force between the mating surfaces to transmit torque or / and axial force. The inner cylinder 2 is divided into the front section 201 and the rear section 202 of the inner cylinder. According to the actual working conditions and performance requirements, different materials or different structural designs are adopted. For example, the front section 201 of the inner cylinder is closer to the air flow inlet and needs to withstand higher pressure and flow rate. Therefore, materials with higher strength and better wear resistance are selected. The rear section 202 of the inner cylinder pays more attention to the cooperation with the outer cylinder 1 and the reflection and absorption of sound waves. Materials with good acoustic performance are selected or special structures are designed to enhance the sound absorption effect. Separated processing can be optimized according to their respective characteristics, improving the processing accuracy and production efficiency, reducing the processing difficulty and cost. At the same time, the front section 201 and the rear section 202 of the inner cylinder are installed separately, which is more convenient than installing the integral inner cylinder 2, improving the assembly accuracy and efficiency, which will not be elaborated here. The interference fit makes the connection between the outer cylinder 1 and the inner cylinder 2 relatively tight, effectively suppressing the relative vibration and collision between the outer cylinder 1 and the inner cylinder 2, and reducing the noise and wear generated by vibration. If the inner cylinder 2 or the outer cylinder 1 is damaged, due to the relatively simple connection method of the interference fit, it is easier to operate when disassembling and replacing parts compared to some complex connection methods. Under the working conditions of the engine, the inner cylinder 2 expands thermally due to temperature changes. The interference fit can compensate for this thermal expansion difference to a certain extent. Through the reasonable design of the interference amount, the outer cylinder 1 and the inner cylinder 2 can still maintain good connection performance and sealing performance under different temperature conditions.

[0028] In this embodiment, the interference fit and fixed connection between the rear section 202 of the inner cylinder and the outer cylinder 1 are realized through a smooth curve transition section. The smooth curve transition section is a smooth curve transition intermediate member 3 or / and is formed by the deformation of the inner cylinder 2 itself. The fixed connection between the rear section 202 of the inner cylinder and the outer cylinder 1 can adopt connection methods such as welding connection or bolt connection in the prior art, which will not be elaborated here. The smooth curve transition section can avoid the appearance of sharp corners or mutations at the welding position, enabling the stress flow to pass through the connection area more smoothly, thereby further reducing the degree of stress concentration and avoiding problems such as crack propagation and structural damage caused by stress concentration. When the exhaust gas flows in the rear section 202 of the inner cylinder, the smooth curve transition section can make the exhaust gas flow more smoothly when passing through the welding part, reducing the vortex and turbulent flow phenomena of the exhaust gas. This not only reduces the flow resistance of the exhaust gas, improves the exhaust gas transportation efficiency, but also reduces the vibration and noise caused by the impact of the exhaust gas, which is beneficial to the stable operation of the muffler. At the same time, compared with the traditional vertical cylinder wall, the smooth curve transition section can delay the degree of thermal expansion and contraction of the inner cylinder 2, avoiding the problem of rupture of the inner cylinder 2 caused by thermal expansion and contraction. The smooth curve transition intermediate member 3 is usually a metal part with a reducing cylinder structure, which has the characteristics of connecting cylinders with different diameters, adjusting the flow rate and pressure of the exhaust gas, adapting to changes in the cylinder layout, and improving the stability of the connection structure, which will not be elaborated here.

[0029] In this embodiment, the rear end of the inner cylinder rear section 202 is interference fit with the outer cylinder 1 through a smooth curve transition middle piece Ⅰ301, and the front end is welded and fixed to the outer cylinder 1 through a smooth curve transition middle piece Ⅱ302. As shown in the figure, the rear end of the inner cylinder rear section 202 is provided with a smooth curve transition middle piece Ⅰ301, and the smooth curve transition middle piece Ⅰ301 is usually a metal piece with a large and small head cylindrical structure. The large head section of the smooth curve transition middle piece Ⅰ301 is interference fit with the outer cylinder 1, and the small head section is backward and sleeved on the inner cylinder rear section 202 and welded and fixed. This connection method can effectively resist the vibration that occurs when the muffler is running. , impact and other external forces to prevent the connection parts from loosening and ensure the stability of the entire structure. The smooth curve transition middle piece Ⅰ301 also has the function of uniformly transmitting stress, and reasonably distributes the external forces acting on the structure to the inner cylinder 2 and the outer cylinder 1 to avoid stress concentration, which helps to extend the service life of the muffler and improve the reliability of the entire structure. In actual production, there will be certain errors in the sizes of the outer cylinder 1 and the inner cylinder rear section 202. The smooth curve transition middle piece Ⅰ301 compensates for the size error through its own elastic deformation, so that the outer cylinder 1 and the inner cylinder rear section 202 can achieve good fit, which improves to a certain extent. The processing technology and assembly success rate of the parts are improved, and the production cost is reduced. During installation, heating or cooling methods can be used to make the smooth curve transition middle piece I301 easier to install, which will not be repeated here; the front end of the inner cylinder rear section 202 is welded and fixed to the outer cylinder 1 through the smooth curve transition middle piece II302, and the inner cylinder 2 and the outer cylinder 1 are further connected into a whole, so that the whole structure can work together when subjected to external force, and has a better ability to resist deformation and damage; the interference fit can reduce the relative movement between the inner cylinder 2 and the outer cylinder 1, and suppress the generation of vibration, and the welding fixation provides a rigid connection, which can have The vibration and impact loads are effectively transferred to the entire structure, avoiding local stress concentration, and improving the stability and reliability of the structure under dynamic loads; the interference fit forms a good sealing effect at the rear end of the inner cylinder rear section 202, which can prevent the internal medium from leaking from the rear end of the inner cylinder rear section 202, and the welding fixation at the front end of the inner cylinder rear section 202 can also ensure the sealing of the connection part. In addition, the setting of the smooth curve transition middle piece Ⅰ301 and the smooth curve transition middle piece Ⅱ302 can reduce the flow resistance of the exhaust gas at the connection, reduce the scouring and erosion of the exhaust gas on the connection part, and further improve the sealing performance.

[0030] In this embodiment, the rear end of the front section 201 of the inner cylinder body is welded to the outer cylinder body 1 through its own smooth curve transition section 2011, and the front end is gradually necked down and welded to the outer cylinder body 1. The smooth curve transition section 2011 of the front section 201 of the inner cylinder body itself can make the stress transfer between the front section 201 of the inner cylinder body and the outer cylinder body 1 more uniform, avoid stress concentration, improve the anti-fatigue performance and stability of the overall connection structure. The design of gradually necking down at the front end of the front section 201 of the inner cylinder body enables the stress at the front end of the front section 201 of the inner cylinder body to change gradually. When bearing external forces, the stress can be gradually transmitted and dispersed along the necked-down part, reducing the risk of excessive local stress, enhancing the connection strength, improving the structural rigidity, and making the deformation of the whole structure smaller when stressed. This will not be elaborated here. At the same time, the smooth curve transition section 2011 and the design of gradually necking down can be relatively easily manufactured into the corresponding shape through appropriate processing techniques such as stamping and forging during the manufacturing process. And during the welding process, due to the regularity of the structure, the welding operation is relatively easy to carry out, improving the production efficiency, ensuring the welding quality, reducing the usage amount of welding materials, and lowering the production cost.

[0031] In this embodiment, the outer cylinder body 1 includes a front section 101 and a rear section 102 of the outer cylinder body. The front end of the rear section 102 of the outer cylinder body is butt-jointed and welded to the rear end of the front section 201 of the inner cylinder body, forming an integral whole. When bearing external forces, they can jointly bear the load, avoiding local stress concentration caused by insecure connection, enhancing the strength and stability of the overall connection structure, preventing the leakage of exhaust gas in the muffler, and ensuring the normal operation of the muffler. The butt welding makes the stress transfer between the outer cylinder body 1 and the inner cylinder body 2 more uniform. When subjected to external loads, the stress can be smoothly transferred from the outer cylinder body 1 to the inner cylinder body 2 through the welded part, avoiding stress mutation, reducing the possibility of damage due to stress concentration, and extending the service life of the muffler.

[0032] In this embodiment, the smooth curve transition middleware II 302 is a reduced-diameter cylindrical structure II. The large-head section of the reduced-diameter cylindrical structure II covers forward the butt joint position between the front end of the rear section 102 of the outer cylinder and the rear end of the front section 201 of the inner cylinder and is welded and fixed. The small-head section extends backward to the inner circle at the front end of the rear section 202 of the inner cylinder and is welded and fixed. This connection method enables a firm overall connection among the outer cylinder, the inner cylinder, and the middleware, allowing each part to work together effectively, avoiding structural failure caused by local loosening, and enhancing the reliability and stability of the overall connection structure. The welding method can provide a high connection strength between components. When bearing tensile force, pressure, and shear force, the welded part can reliably transmit the load, ensuring the safe operation of the structure under complex working conditions. The smooth curve transition middleware II 302 has good elastic deformation ability. When the muffler generates stress due to factors such as temperature change and pressure fluctuation during operation, the reduced-diameter cylindrical structure II of the smooth curve transition middleware II can absorb and disperse the stress through its own deformation, dispersing the concentrated stress along its smooth curve to a larger area, avoiding stress concentration at the connection part, thereby reducing the risk of cracking at the butt joint and weld position between the front end of the rear section 102 of the outer cylinder and the rear end of the front section 201 of the inner cylinder and damage to the inner cylinder 2 and the outer cylinder 1. At the same time, the small-head section of the reduced-diameter cylindrical structure II extends backward to the inner circle at the front end of the rear section 202 of the inner cylinder, making the smooth curve transition middleware II 302 form a fixed connection with the rear section 202 of the inner cylinder, enhancing the stability of the connection, which will not be elaborated here;

[0033] The smooth curve transition intermediate piece I 301 is a reduced-diameter cylindrical structure I. The small-diameter section of the reduced-diameter cylindrical structure I faces backward and is sleeved outside the rear section 202 of the inner cylinder and is fixed by welding. The large-diameter section is in interference fit with the rear section 102 of the outer cylinder; or the small-diameter section of the reduced-diameter cylindrical structure I faces backward and is sleeved outside the rear section 202 of the inner cylinder and is in interference fit, and the large-diameter section is fixed by welding with the rear section 102 of the outer cylinder. In this embodiment, the small-diameter section of the reduced-diameter cylindrical structure I faces backward and is sleeved outside the rear section 202 of the inner cylinder and is fixed by welding, which can provide reliable connection strength and ensure that there is no relative displacement between the smooth curve transition intermediate piece I 301 and the rear section 202 of the inner cylinder during the operation of the muffler. The large-diameter section of the reduced-diameter cylindrical structure I is in interference fit with the rear section 102 of the outer cylinder, so that the smooth curve transition intermediate piece I 301 is tightly combined with the rear section 102 of the outer cylinder. Through the frictional force and extrusion force generated by the interference amount, the stability of the connection is enhanced, and it can effectively withstand various forces generated during the operation of the equipment, such as pressure or vibration, etc., reducing the possibility of failures caused by loose connections; the setting of the smooth curve transition intermediate piece I 301 helps to reduce the stress concentration phenomenon. During the operation of the muffler, when the exhaust gas flows in the inner cylinder 2 or the outer cylinder 1 is subjected to external load, the smooth curve can make the stress more evenly distributed on the overall structure, reducing the risk of excessive local stress, improving the reliability and safety of the overall structure, and extending the service life of the muffler; of course, it can also be that the small-diameter section of the reduced-diameter cylindrical structure I faces backward and is sleeved outside the rear section 202 of the inner cylinder and is in interference fit, and the large-diameter section is fixed by welding with the rear section 102 of the outer cylinder, which has the same connection effect and will not be elaborated here.

[0034] In this embodiment, the rear end of the front section 101 of the outer cylinder is sleeved outside and welded to the rear end of the front section 201 of the inner cylinder. A bellows 4 is used to transition and is welded between the front section 101 and the rear section 102 of the outer cylinder. The rear end of the front section 101 of the outer cylinder is sleeved outside and welded to the rear end of the front section 201 of the inner cylinder, forming a relatively large welding contact area. This not only enhances the connection strength between the outer cylinder 1 and the inner cylinder 2, enabling it to withstand greater external forces and internal pressures, but also improves the structural sealing performance, effectively preventing the leakage of exhaust gas. The way of sleeving and welding the rear end of the front section 101 of the outer cylinder makes the stress transfer more uniform, avoiding stress concentration. When subjected to external forces, the stress can be dispersed more smoothly to the entire cylinder through the welded part, reducing the risk of structural damage caused by excessive local stress and extending the service life of the muffler. This will not be elaborated here. Usually, the welded connection position is a weak area in the connection structure and is prone to stress concentration when stressed. The bellows 4 can disperse the stress at the welded connection position to a larger area, avoiding excessive stress concentration at the welded connection position, thereby reducing the risk of cracking at the welded connection position, increasing the connection stiffness, making the connection between the bellows 4 and the front section 101, the rear section 102 of the outer cylinder, and the front section 201 of the inner cylinder more firm, enabling it to better resist external forces and ensuring stability under complex working conditions. It also enhances the sealing performance of the welded connection position, filling the tiny gaps existing at the welded connection position, preventing exhaust gas from leaking into the external environment, and ensuring the normal operation of the muffler. The bellows 4 also has a protective effect, preventing erosion media such as liquids and gases outside the muffler from entering the inside of the welded connection position, thereby slowing down the corrosion rate of the welded connection position and extending the service life of the muffler. This will not be elaborated here.

[0035] In this embodiment, a catalytic converter 5 is further included. The catalytic converter 5 is located at a position close to the front of the front section 201 of the inner cylinder. The catalytic converter 5 is used to convert harmful substances in the engine exhaust gas. It usually contains noble metal catalysts such as platinum, palladium or rhodium, etc., which can promote chemical reactions of carbon monoxide, hydrocarbons and nitrogen oxides in the engine exhaust gas to be converted into harmless substances such as carbon dioxide, water and nitrogen, reducing environmental pollution. Since the temperature of the exhaust gas discharged from the engine is relatively high when it first enters the muffler, the front section 201 of the inner cylinder can maintain a relatively high temperature. At the same time, the catalytic converter 5 can achieve the best catalytic effect only within a certain temperature range. Setting the catalytic converter 5 at a position close to the front of the front section 201 of the inner cylinder can make full use of the heat in the exhaust gas, enabling the catalytic converter 5 to reach the operating temperature faster and improving the conversion efficiency. The front end part of the catalytic converter 5 is welded and fixed to the front section 201 of the inner cylinder, and the rear end part is connected to a connecting pipe arranged in the inner cylinder 1. The catalytic converter 5 covers the connection position between the connecting pipe and the front section 201 of the inner cylinder and is welded and fixed, so that the catalytic converter 5, the connecting pipe and the front section 201 of the inner cylinder form an integral body, ensuring that there is no relative displacement or looseness between the components, and increasing the connection strength. A bellows 2012 is provided between the connecting pipe and the front section 201 of the inner cylinder. The bellows 2012 is a smoothly transitioning convex part at a position close to the front of the front section 201 of the inner cylinder, which has a protective function to prevent erosion media such as liquid and gas outside the muffler from entering the inside of the welded connection position, thereby slowing down the corrosion rate of the welded connection position and extending the service life of the muffler, which will not be elaborated here. An expansion joint 1011 sleeving the bellows 2012 is further provided on the front section 101 of the outer cylinder. The expansion joint 1011 can reduce the turbulence and eddy current generated by the air flow near the welded connection position, and reduce the additional pressure impact on the welded connection position. At the same time, under the working conditions of the muffler, due to the influence of internal pressure, temperature changes and the external environment, various stresses are generated. The bellows 2012 and the expansion joint 1011 can change the stress distribution around the welded connection position, disperse the stress to a larger area, avoid stress concentration at the welded connection position, improve the strength and stability of the entire structure, and prevent cracking of the welded connection position or deformation of the inner cylinder 2 caused by stress concentration.

[0036] The front section 201 of the inner cylinder body and the front section 101 of the outer cylinder body are partially closely attached to the catalytic converter 5, and a corresponding resonance cavity is formed on the corresponding side. This design makes the integration degree of the overall structure higher, the connection between components more tight and stable, helps to reduce the vibration and noise of the overall structure during operation, improves the overall stability and reliability, effectively utilizes the space, makes the muffler more compact, combines the catalytic converter 5 with the resonance cavity, reduces the overall size and floor area of the muffler, is convenient for installation and layout in a limited space, simplifies the installation and maintenance process, and reduces the maintenance cost; the existence of the resonance cavity can, to a certain extent, suppress the influence of external interference on the catalytic conversion process. The resonance cavity serves as an acoustic or mechanical buffer zone, reducing the interference of external vibration, noise or other fluctuating factors on the internal reaction of the catalytic converter 5, making the catalytic conversion process more stable and reliable, and extending the service life of the catalytic converter 5. This will not be elaborated here.

[0037] In this embodiment, the inner cylinder body 2 is divided into several resonance cavities by several partition plates 6. The exhaust pipe 7, the intake pipe 9 and the resonance pipe 10 are correspondingly supported on the corresponding partition plates 6. The exhaust pipe 7, the intake pipe 9 and the resonance pipe 10 are supported on the corresponding partition plates 6 by interference fit. By dividing the inner cylinder body 2 into several resonance cavities by several partition plates 6, the structure of the inner cylinder body 2 becomes more stable, can withstand a certain pressure and external force, and is not easily deformed. At the same time, the partition plates 6 play a supporting role for the exhaust pipe 7, the intake pipe 9 and the resonance pipe 10, and the interference fit method further enhances the stability of the connection, ensuring that the exhaust pipe 7, the intake pipe 9 and the resonance pipe 10 will not easily shake or fall off during the operation of the muffler, guaranteeing the stability and reliability of the overall structure, and also helping to improve the sealing performance between the exhaust pipe 7, the intake pipe 9 and the resonance pipe 10 and the corresponding partition plates 6, reducing the possibility of gas leakage; dividing the inner cylinder body 2 into multiple resonance cavities can guide the tail gas to flow along a specific path, making the flow of the tail gas more stable, reducing the pressure fluctuation and turbulence of the air flow, reducing the additional noise generated by the unstable air flow, and also helping to reduce the impact on the muffler structure, improving the reliability of the muffler and extending its service life. At the same time, according to different working requirements and frequency requirements, each resonance cavity is independently designed and optimized to achieve specific resonance functions and improve the performance of the muffler; in the prior art, the exhaust pipe 7 is correspondingly arranged on the partition plate 6 far from the front section of the inner cylinder body, and the intake pipe 9 and the resonance pipe 10 are correspondingly arranged between two adjacent partition plates 6 in the rear section 202 of the inner cylinder body. This will not be elaborated here; the intake pipe 9 refers to the exhaust pipe connected to the catalytic converter 5. This will not be elaborated here; the resonance pipe 10 is connected between adjacent resonance cavities. When the tail gas flows between the resonance cavities, the resonance pipe 10 can cause the vibration and disturbance of the tail gas, increase the contact area and contact time between the tail gas and the inner surface of the inner cylinder body 2, and improve the sound absorption effect.

[0038] In this embodiment, a post-oxygen sensor 8 is further provided on the front section 201 of the inner cylinder body. The post-oxygen sensor 8 is mainly used to detect the oxygen concentration in the exhaust gas after being treated by the catalytic converter 5, which will not be elaborated here. Since the outer cylinder body 1 and the inner cylinder body 2 adopt a segmented design, compared with the traditional integral outer cylinder body 1 and inner cylinder body 2, the overall length of the outer cylinder body 1 and the inner cylinder body 2 is shortened by half. Under the same working environment, according to the telescopic amount calculation formula, the telescopic rate of the inner cylinder body 2 is reduced by 50%, reducing the telescopic amount of the inner cylinder body 2 due to thermal expansion and contraction. Therefore, the risk of the post-oxygen sensor 8 being torn from the front section 201 of the inner cylinder body is reduced, which will not be elaborated here.

[0039] The motorcycle of this embodiment includes the segmented muffler described above. An interference fit installation method is at least partially adopted between the inner cylinder body 2 and the outer cylinder body 1, and the inner cylinder body 2 and the outer cylinder body 1 are designed in a segmented manner. Compared with the conventional integral inner cylinder body 2 structure, the overall length of the inner cylinder body 2 is shortened, the telescopic amount of the inner cylinder body 2 due to thermal expansion and contraction is reduced, the problem of the inner cylinder body 2 being cracked due to thermal expansion and contraction is solved, and the risk of tearing at the connection position between the inner cylinder body 2 and the post-oxygen sensor 8 is also reduced, improving the stability of the muffler. The catalytic converter 5 is arranged at a position close to the front of the front section 201 of the inner cylinder body and fixed by welding, increasing the support strength of the catalytic converter 5, improving the conversion efficiency of the catalytic converter 5, reducing the use cost, and achieving the goal of green emission.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, 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 purpose and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A segmented muffler, characterized in that: The invention comprises an outer cylinder and an inner cylinder, wherein the inner cylinder comprises an inner cylinder front section and an inner cylinder rear section, and at least one end of the inner cylinder rear section is interference fit with the outer cylinder.

2. The segmented muffler according to claim 1, characterized in that: The interference fit and fixed connection between the rear section of the inner cylinder and the outer cylinder are achieved through a smooth curve transition section, which is a smooth curve transition middle piece and / or is formed by deformation of the inner cylinder itself.

3. The segmented muffler according to claim 2, characterized in that: The rear end of the rear section of the inner cylinder is interference fit with the outer cylinder through a smooth curve transition middle piece I, and the front end is welded and fixed to the outer cylinder through a smooth curve transition middle piece II.

4. The segmented muffler according to claim 1, characterized in that: The rear end of the front section of the inner cylinder is welded to the outer cylinder through its own smooth curve transition section, and the front end is gradually necked and welded to the outer cylinder.

5. The segmented muffler according to claim 3 or 4, characterized in that: The outer cylinder comprises an outer cylinder front section and an outer cylinder rear section, and the front end of the outer cylinder rear section is butted and welded with the rear end of the inner cylinder front section.

6. The segmented muffler according to claim 3 or 5, characterized in that: The smooth curve transition middle piece II is a large and small head cylindrical structure II, the large head section of the large and small head cylindrical structure II covers the front end of the rear section of the outer cylinder body and the rear end of the front section of the inner cylinder body and is welded and fixed, and the small head section extends backward to the front end inner circle of the rear section of the inner cylinder body and is welded and fixed; The smooth curve transition middle piece I is a large and small head cylindrical structure I, the small head section of the large and small head cylindrical structure I is backward and outer sleeved on the rear section of the inner cylinder and fixed by welding, and the large head section is interference fit with the rear section of the outer cylinder; or the small head section of the large and small head cylindrical structure I is backward and outer sleeved on the rear section of the inner cylinder and interference fit, and the large head section is fixed with the rear section of the outer cylinder by welding.

7. The segmented muffler according to claim 5, characterized in that: The rear end of the front section of the outer cylinder is sleeved on the rear end of the front section of the inner cylinder and fixed by welding. The front section of the outer cylinder and the rear section of the outer cylinder are transitioned through an expansion joint and fixed by welding.

8. The segmented muffler according to claim 1 or 5, characterized in that: It also includes a catalytic converter, which is located at the front of the front section of the inner cylinder; The front section of the inner cylinder and the front section of the outer cylinder are arranged closely to the catalytic converter, and the corresponding sides form corresponding resonance cavities.

9. The segmented muffler according to claim 1, characterized in that: The inner cylinder is divided into a plurality of resonance cavities by a plurality of partitions, and an exhaust pipe, an air intake pipe and a resonance pipe are supported correspondingly on the plurality of partitions. The exhaust pipe, the air intake pipe and the resonance pipe are supported on the corresponding partitions by interference fit.

10. A motorcycle, characterized in that: A segmented muffler comprising any one of claims 1 to 9.

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