Coaxial Vehicle Muffler Structure for Additional Frequency Attenuation
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Solution Overview
Problem
Existing vehicle silencers for charge air lines with turbochargers lack a simple yet effective structure for attenuating additional frequency spectra, and they often compromise on robustness and mass due to material limitations.
Innovation Solution
A vehicle silencer design featuring a first and second housing part forming an outer shell with an inner resonator element, creating two resonator chambers and an annular space between outer and inner tube sections, allowing for pressure wave transmission and adjustable frequency spectrum attenuation, with options for metallic or plastic materials to enhance robustness and reduce mass.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If an additional frequency spectrum is to be attenuated, then the sound attenuation effectiveness is improved, but the device complexity increases
Solution Approach 1:
The resonator inner element is nested within the housing parts, with the annular space formed between the outer tube section and the outer jacket. This nesting arrangement allows the additional frequency attenuation function to be integrated into the existing structure without requiring separate components, thereby improving sound attenuation effectiveness while avoiding increased device complexity.
Solution Approach 2:
The annular space is formed by utilizing the radial dimension between the outer tube section and the outer jacket, rather than adding length in the axial dimension. This dimensional approach allows pressure waves to be transmitted through an additional path for attenuating another frequency spectrum, improving effectiveness without significantly increasing the overall device size or complexity.
2Reliability
If metallic housing parts are used, then robustness and temperature resistance are improved, but mass increases
Solution Approach 1:
The silencer employs a composite material strategy where the housing parts are made of metallic material for robustness and temperature resistance, while the resonator inner element is made of plastic material to reduce mass. This combination allows the system to achieve the desired reliability without excessive mass increase, as the plastic inner element compensates for the weight of the metallic housing.
3Weight of stationary object
If the resonator inner element is made of plastic material, then mass is reduced and vibration properties are improved, but temperature resistance and robustness deteriorate
Solution Approach 1:
Different parts of the silencer are assigned different material qualities according to their functional requirements. The housing parts, which require temperature resistance and robustness, are made of metallic material. The resonator inner element, which benefits from low mass and good vibration properties, is made of plastic material. This local differentiation of material properties allows each component to optimize its performance for its specific function while the overall system achieves a balance between mass and reliability.
4Object-generated harmful factors
If the annular space gap width is reduced to improve sound attenuation, then the frequency spectrum attenuation is improved, but the manufacturing precision requirements increase
Solution Approach 1:
The silencer is divided into separately manufacturable components (housing parts and resonator inner element) that are assembled together. The annular space is formed between these assembled components rather than being a monolithic feature. This segmentation allows the gap width to be controlled through the design of standardized connection features and positioning elements, reducing the overall manufacturing precision requirements compared to forming the entire annular space in a single machining operation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design effectively attenuates additional frequency spectra while maintaining structural robustness and minimizing mass, allowing for efficient sound attenuation and cost-effective series production.
Implementation Method 1
at least a first and a second resonator chamber are formed by the two housing parts and the resonator inner element... pressure waves in the first or second resonator chamber can be transmitted via the annular space
Data Source
Figure 1~3
Figure 2
Figure 4~5
AI summary
The invention relates to a vehicle silencer (1). The vehicle silencer (1) comprises a first housing part (2) having a first outer casing (10) and a second housing part (3) having a second outer casing (21). The vehicle silencer (1) also comprises a resonator inner element (31) that is interlockingly accommodated in at least one of the housing parts (2, 3), and at least one chamber separation wall (17), as well as at least one first inner pipe section (15) connecting to an inner perimeter (51) of the chamber separation wall (17), wherein at least one first (6) and a second resonator chamber (7) are formed by the two housing parts (2, 3) and the resonator inner element (31). The resonator element (31) has at least one first outer pipe section (42) connecting to an outer perimeter (37) of the chamber separation wall (17), said pipe section being formed coaxially to the first inner pipe section (15) of the resonator inner element (31), wherein an annulus (44) is formed between the outer pipe section (42) and the first outer casing (10) and/or the second outer casing (21).