CN111169221A

CN111169221A - Wheel with sound absorption device

Info

Publication number: CN111169221A
Application number: CN201911343993.1A
Authority: CN
Inventors: 徐世文; 冯树伟; 李明磊; 郎玉玲; 黄少兵; 胡铁峰; 陈铭博; 王大东; 刘伟东
Original assignee: Citic Dicastal Co Ltd
Current assignee: Citic Dicastal Co Ltd
Priority date: 2019-12-24
Filing date: 2019-12-24
Publication date: 2020-05-19

Abstract

The present application relates to a wheel with sound absorption means, which are installed inside a wheel air chamber (30) for reducing acoustic resonance, wherein the sound absorption means comprise at least one integrally formed cassette sound absorber unit (10) or at least one cassette sound absorber assembly integrally combined by a plurality of sound absorber units, which are bound to a hub (20) of the wheel by means of a binding element (50). According to the technical scheme provided by the invention, the noise reduction effect is improved, and meanwhile, the sound absorption device is simpler, more convenient and more economical to manufacture and install.

Description

Wheel with sound absorption device

Technical Field

The invention relates to a wheel with sound absorption means, in particular a vehicle wheel equipped with a pneumatic tyre.

Background

In the normal running process of the vehicle, the excitation of the road surface to the wheels and the excitation of the wheel axle to the wheels caused by the rotation unbalance of the wheels can excite an air chamber in the wheels to generate acoustic resonance, and the resonance is transmitted to a vehicle body structure through the wheel axle and a suspension system and then radiates noise in the vehicle. The noise characteristics of the car noise suppression device are mainly low-frequency narrow bands, the magnitude is high, noise interference is formed for the interior passenger environment of the car, and effective control is needed.

Currently, there are numerous studies and patents that provide methods to effectively control such acoustic resonances. The method mainly adopts a sound absorption control principle, wherein the Helmholtz resonance sound absorption is widely applied and has a good effect. For example, chinese patents CN101301842B, CN104981359B, CN105209267B, and CN104908513B relate to a series of wheel solutions implemented based on helmholtz resonator noise reduction method. However, in the solutions known from the prior art, the constructive design and mounting structure of the helmholtz resonator is complex and also not ideal in terms of its sound absorption effect. In particular, since the conditions during four-wheel driving are different, there are a plurality of narrow-band high-value noises with different distribution characteristics, so that the noises present a larger noise value in a wider frequency band, which is contrary to the advantages of helmholtz narrow-band sound absorption. Therefore, the structure based on the helmholtz sound absorption principle still needs to be continuously developed and improved. Meanwhile, the structure based on the principle is various, and a space for further improvement is provided in the aspects of amplitude and bandwidth control. In addition, the helmholtz sound absorption principle is also suitable to be combined with other noise reduction principles (such as box-type structure resonance sound absorption) to make up for the deficiency of the helmholtz principle, so that the efficiency of controlling the resonance of the air chamber can be effectively improved, but the integration of various noise reduction principles at present is not popularized and applied in the aspect of reducing the acoustic resonance of the wheel air chamber.

Further, in the case of the above-described prior art, the structural design and mounting structure of the helmholtz resonator are complicated, and for this reason, the resonator member ("sub-air chamber member") is structured with a flange-like thin plate flange ("rim portion"), a groove ("groove portion") is formed in a wall surface specially structured in the boss, and the resonator member is fixed and positioned by the flange-like thin plate flange and the groove portion of the wall surface, and this engagement mechanism is difficult to secure the connection strength due to its thin-walled feature, and on the other hand, since the connection and fitting of both the members are basically dependent on the structural dimensional accuracy, it is highly required for the processing and manufacturing of the members, and moreover, the alignment and mounting work of both the members is troublesome, and the final mounting and fastening force cannot be controlled.

Furthermore, KR101822271B1 discloses an aluminum wheel, wherein resonator tubes are mounted along the circumference of the rim, and the resonator tubes are fixed by: the rim is provided with a single side wall extending along the circumferential direction of the rim, and the single side wall is provided with a buckling bulge extending towards the center of the rim; a flange at one side and a flange at the other side are formed at two sides of the resonance tube; the resonance tube is inserted into and hooked on the buckling bulge by a flange at one side, threads are formed on the flange at the other side, and the resonance tube is matched and fixed on the circumferential surface of the wheel rim by a nut member matched with the resonance tube. For such a fixing scheme of the resonator tube, there are also problems of unreasonable structure, high manufacturing requirements, inconvenient assembly and the like, and importantly, the final mounting and fastening force is still difficult to control.

Disclosure of Invention

The present invention proposes a wheel with a sound absorber, which partially or completely overcomes the above-mentioned drawbacks of the prior art, and in particular, improves the noise reduction effect while making the manufacture and installation of the sound absorber (or resonator) simpler and more economical.

To this end, the invention provides a wheel with sound absorption means mounted inside the air chamber of the wheel for reducing acoustic resonances, characterized in that the sound absorption means comprise at least one integrally formed cassette sound absorber unit or at least one cassette sound absorber assembly consisting of a plurality of sound absorber units integrated, the cassette sound absorber unit or the cassette sound absorber assembly being bound to the hub of the wheel by means of a binding element.

The technical scheme provided by the invention is mainly based on the following ideas: the sound absorption device is formed by adopting the integrally formed sound absorber units, so that the realization of modular and standardized mass production of the sound absorption device is supported; and secondly, the sound absorber unit is fixed by adopting a binding element with a tensioning effect, so that the convenient and controllable installation operation is allowed to be implemented, and meanwhile, the wheel assembly (particularly the sound absorber module) is convenient to disassemble and assemble, thereby being beneficial to later maintenance and replacement of spare parts.

According to one embodiment, the cassette sound absorber unit or the cassette sound absorber subassembly is a cuboid box integrally formed from a metal material or a plastic material.

According to one embodiment, the cassette sound absorber unit or the cassette sound absorber assembly is a cuboid box produced by a 3D printing process, preferably made of a plastic material.

According to the present invention, the sound absorber unit (or the sound absorber assembly composed of a plurality of sound absorber units) is of a box-type configuration. Accordingly, the cassette-type sound absorber unit has two side faces which delimit the two ends of the cassette in the circumferential direction of the wheel hub, wherein one end forms an open-end side face with an opening into the interior cavity of the cassette and the other end forms a closed-end side face.

In order to improve the resonance control effect of the wheel air chamber, the invention provides a special optimization design aiming at a sound absorption device (or a sound absorber unit), and the key points of the design idea comprise: by adopting a double-layer porous resonance sound absorption structure, the defects that the low-frequency sound absorption capability is difficult to improve under the limited volume and the sound absorption frequency band is narrow in single Helmholtz resonance sound absorption are overcome on the control principle; the box-type sound absorption structure is a rectangular hexahedral box-type structure, is preferably made of plastic materials, and is designed to have the structural resonance frequency consistent with that of the air chamber, so that the sound absorption quantity is further increased on the basis of double-layer porous resonance sound absorption, and the sound absorption frequency band is expanded. In addition, with regard to the design of the sound absorption device (or sound absorber unit) construction, it is also to be ensured that the shaping thereof can be carried out by means of suitable production techniques, and that the sound absorption structure according to the invention can be produced efficiently by means of a 3D printing process, which facilitates the flexible production of the cassette sound absorber unit and/or the cassette sound absorber assembly.

It should be noted that the "cuboid shape" in the present application is not strictly limited to a regular cuboid shape in a geometric sense, but may substantially have a shape similar to a cuboid, wherein one or more faces are configured to have a certain curvature (e.g., the bottom surface of the case has a circular arc shape adapted to the contour of the outer surface of the rim) and/or have a local convex or concave structure (e.g., for installation or fixation), the intersecting faces may not be absolutely orthogonal, and the opposing faces may not be absolutely parallel, without affecting the implementation of the technical solution of the present invention.

According to one embodiment, it is advantageous that the cassette sound absorber unit forms a porous double-layer helmholtz resonance sound absorption structure, wherein the interior of the box body of the box type sound absorber unit is divided into a first cavity and a second cavity which are sequentially arranged along the circumferential direction of the wheel hub through a partition plate, two hollow tube orifices are formed on the open end side, the orifices of the two hollow tubes open to the wheel air chamber and the two hollow tubes extend into the first cavity at a distance corresponding to the tube length thereof, a nozzle of one hollow tube is formed on the partition plate, the nozzle of the one hollow tube opens into the first cavity and the one hollow tube extends into the second cavity by a distance corresponding to the tube length thereof, the first cavity and the second cavity form two layered resonant cavities of the porous double-layer Helmholtz resonance sound absorption structure.

It is further advantageous that the structural parameters of the case-type sound absorber unit, including the thickness of the partition plate and the plate bodies on the open-end side and the closed-end side, the orifice diameter and the tube length of each of the hollow tubes, and the shape, volume and wall thickness of the first cavity and the second cavity, are determined by a predetermined sound absorption coefficient and sound absorption amount of the porous double-layer helmholtz resonance sound absorbing structure.

According to one embodiment, the cassette type sound absorber assembly is formed by combining two of the cassette type sound absorber units with their closed end sides joined. By adopting the sound absorber component, the situation that the sound absorbing structure is installed inversely in the way of meeting the flow caused by misorientation is not needed to be worried about during installation, and in the actual use process, the wheels provided with the corresponding sound absorbing devices can be randomly exchanged without influencing the noise reduction effect.

Advantageously, the cassette sound absorber unit or the cassette sound absorber assembly itself forms a structural resonance sound absorber, as which the first order natural mode frequency coincides with the first order natural mode frequency of the wheel air chamber.

According to one embodiment, a plurality of said cassette sound absorber units or said cassette sound absorber assemblies are arranged side by side on the hub of the wheel or distributed along the circumference of the hub to optimize or adapt the sound absorption and noise reduction requirements of the wheel as a whole or the dynamic balance characteristics thereof. In particular, a plurality of cassette-type sound absorber units or cassette-type sound absorber assemblies may be arranged uniformly along the circumferential direction of the wheel hub, for example, two cassette-type sound absorber units (or cassette-type sound absorber assemblies) may be arranged symmetrically along the circumferential direction of the wheel hub, that is, mounted opposite to each other in the wheel diameter direction, for the specific case of a particular vehicle type.

According to one embodiment, the cassette sound absorber unit or the cassette sound absorber assembly rests with the bottom side of the cassette against the outer rim surface of the hub in the installed state. In this connection, it is expedient if the cassette sound absorber unit or the cassette sound absorber module is provided with at least one bend extending transversely of its cassette body, which divides the cassette sound absorber unit or the cassette sound absorber module in its cassette body longitudinal direction into at least two sections in order to adapt the cassette body base to the circular-arc-shaped contour of the outer surface of the rim in the mounted state. For the cassette sound absorber unit, for example, the bent portion may be provided between the first chamber and the second chamber; for the cassette type sound absorber module, for example, the bent portion may be additionally provided at the connecting portion of the sound absorber unit. The bending part can be designed as a material weak part of the box body, can be continuous or discontinuous along the transverse direction of the box body, can transversely extend through the box body, and can also only extend on a part of the transverse section of the box body.

According to one embodiment, the binding element is a strap (for example, a steel band) which is pressed from the top side of the casing of the cassette sound absorber unit or the cassette sound absorber assembly against the outer surface of the rim of the wheel hub and fastens the cassette sound absorber unit or the cassette sound absorber assembly around the wheel hub, the two ends of the strap being fixedly connected by snap-on fastening, the strap tension being adjustable and/or displayable by means of a fastening tool.

In this connection, it is advantageous if the cassette sound absorber unit or the cassette sound absorber module is provided on its box top face with a U-shaped recess for the insertion of the strap.

According to a further embodiment, the restraining element is a carrier strip (for example a steel strip) to which the cassette sound absorber unit or the cassette sound absorber assembly is pre-fastened to form a pre-assembled unit, which is fastened by the carrier strip being wound around the hub and tightened around the outer surface of the rim.

In this connection, it is possible that the cassette sound absorber unit or the cassette sound absorber module is fitted with its cassette bottom face and the carrier tape establishing face and adhesively fixed to the carrier tape so that they are firmly joined to form a preassembled unit.

The cassette absorber unit or the cassette absorber assembly can also be fastened to the carrier strip by means of suitable fasteners, such as adhesive tape, clips, screws or the like.

Thus, according to the present invention, a structure for reducing acoustic resonance of a wheel air chamber mounted on a wheel hub can be realized. The specific implementation is a box-shaped structure which is in a cuboid shape, two cavities are formed by dividing a layer of thin plate in the box-shaped structure, two hollow pipes are connected to one side face (parallel to the thin plate divided in the box) of the box-shaped structure, the thin plate divided in the box is connected with one hollow pipe, the pipe orifice plane at one end of each hollow pipe and the side face of the box-shaped structure are on the same face, the pipe length extends into the cavities, the pipe orifice plane at one end of each hollow pipe and the thin plate divided in the box are on the same face, and the pipe length extends into the other cavity. The two hollow pipes of the structure are communicated with the tire air chamber and are arranged on the circumferential surface of a circular arc of the hub to form a porous double-layer Helmholtz resonance sound absorption structure. Compared with single-cavity single-hole type Helmholtz resonance sound absorption, the structure is easier to be designed to be close to low frequency, and the sound absorption frequency band is wider. And relevant parameters of the structure are determined by using the sound absorption coefficient and the sound absorption quantity of the double-layer Helmholtz resonance sound absorption structure.

The box-type structure is preferably made of plastic materials with certain rigidity and strength, clings to the circular arc circumference of the hub and is fixedly installed by utilizing a steel belt. In the structure in the installation mode, the first-order natural modal frequency of the structure is consistent with the first-order natural modal frequency of the wheel air chamber, and a structural resonance sound absorption structure is formed.

The natural mode of the structure meets the design requirements through plate thickness and shape adjustment, and the adjustment needs to be realized through finite element calculation. On one hand, the design of the sound absorption structure can further increase the sound absorption quantity of the porous double-layer resonance sound absorption structure, and the sound absorption bandwidth can also be further increased through the design.

The box-type sound absorption structure consisting of the porous double-layer resonance sound absorption and the structural resonance sound absorption has the advantages that the upper surface can be designed with the U-shaped groove, and the mounting mode of the box-type structure is that a steel belt is utilized to pass through the U-shaped groove and is fixed around the hub in a circle. It is also possible to arrange a plurality of cassette sound-absorbing structures on the hub according to the actual needs and the specific design situation, and a steel belt is wound around the hub to fix the several cassette sound-absorbing structures on the hub together. The steel band junction is fastened with the buckle, and fastening force can show with fastening tool to judge the firm degree of installation.

Based on the optimized design of the sound absorption device, the invention can also realize the following beneficial technical effects: the comprehensive sound absorption structure composed of porous double-layer resonance sound absorption and structural resonance sound absorption realizes more effective sound absorption effect, and the sound absorption effect is embodied as follows: firstly, the sound absorption frequency is easier to approach to the low frequency; secondly, the sound absorption frequency band is wider; thirdly, the sound absorption capacity is higher.

Drawings

Fig. 1 is a schematic view of the mounting of a sound absorber unit on a wheel.

Fig. 2 is a schematic view of a sound absorber unit arranged on a wheel hub according to a first embodiment.

Fig. 3 is a schematic view of a sound absorber unit arranged on a wheel hub according to a second embodiment.

Fig. 4A is a schematic view of the principle of construction of a first embodiment of the sound absorber unit.

Fig. 4B is a schematic view of the construction principle of a second embodiment of the sound absorber unit.

Fig. 4C is a schematic view of the construction principle of a sound absorber assembly.

Fig. 5 is a perspective view of an acoustic absorber assembly in physical appearance.

FIG. 6 is a perspective view of an example wheel having a sound absorbing device showing a suction assembly secured to the hub of the wheel.

Figure 7 is a perspective view of the combination of the aspirator assembly and the restraining element used in the example of figure 6.

FIG. 8 is a graph showing the noise level spectrum measured in the vehicle under the condition that the wheels of the vehicle are not provided with the resonance sound absorption structure, the vehicle is provided with the resonance sound absorption structure according to the prior art and the vehicle is provided with the resonance sound absorption structure according to the present invention in the road running test at the vehicle speed of 15 km/h.

FIG. 9 is a graph showing the noise level spectrum measured in the vehicle under the condition that the wheels of the vehicle are not provided with the resonance sound absorption structure, the vehicle is provided with the resonance sound absorption structure according to the prior art and the vehicle is provided with the resonance sound absorption structure according to the present invention in the road running test at the vehicle speed of 30 km/h.

Wherein: 1-side of the opening end of the box body, 1' -side of the closed end of the box body, 2-hollow pipe, 3-hollow pipe, 4-first cavity, 5-partition board, 6-hollow pipe, 7-second cavity and 8-U-shaped groove; 9-bend, 9' -bend, 10-absorber unit, 20-hub, 30-wheel air chamber, 40-tire, 50-binding element.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "first," "second," "third," "fourth," and the like in the description and claims of this application and in the accompanying drawings are used for distinguishing between different objects and not for describing a particular order. Furthermore, the terms "comprising" and "having," as well as any variant thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of steps or elements is not limited to those listed but may alternatively include other steps or elements not listed or inherent to such process, method, article, or apparatus. It will be understood by those skilled in the art that throughout the present specification and claims, the terms "longitudinal," "lateral," "up," "down," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings for the convenience of description and simplicity of description, and do not indicate or imply that the device, mechanism, structure, or element being referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore the terms should not be construed as limiting the invention.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

The present application provides a wheel, in particular a motor vehicle wheel provided with a pneumatic tyre 40, with sound absorbing means mounted inside the wheel air chamber 30 for reducing acoustic resonances, as shown in fig. 1, wherein said sound absorbing means comprise at least one integrally formed cassette-type sound absorber unit 10 or at least one cassette-type sound absorber assembly integrated by a plurality of sound absorber units, said cassette-type sound absorber unit or said cassette-type sound absorber assembly being bound to the hub 20 of the wheel by means of binding elements 50 (see fig. 2 and 3).

Fig. 2 is a schematic view of a sound absorber unit arranged on a wheel hub according to a first embodiment. Accordingly, the binding element 50 is a band (e.g., a steel band) which presses the cassette type sound absorber unit 10 or the cassette type sound absorber assembly from the top surface of the case body thereof toward the outer surface of the rim of the wheel hub and fastens the cassette type sound absorber unit 10 or the cassette type sound absorber assembly around the hub 20, both ends of the band are fixedly connected by a snap, and the tension of the band can be set and/or displayed by means of a fastening tool. Suitably, the cassette sound absorber unit 10 or the cassette sound absorber assembly is provided with a U-shaped groove 8 on the top face of its case for inserting the strap (see fig. 4A).

According to the actual requirement, a plurality of the cassette type sound absorber units 10 or the cassette type sound absorber assemblies can be arranged on the hub 20 of the wheel side by side, or a plurality of the cassette type sound absorber units 10 or the cassette type sound absorber assemblies can be arranged along the circumferential direction of the hub.

Fig. 3 is a schematic view of the sound absorber unit provided on the wheel hub according to a second embodiment, in which two cassette type sound absorber units (or cassette type sound absorber modules) are arranged symmetrically in the circumferential direction of the hub, that is, installed opposite to each other in the wheel diameter direction.

As an alternative to the assembly of the cassette sound absorber unit or the cassette sound absorber assembly by means of a binding element on the wheel hub, the binding element 50 can also be designed as a carrier band (for example, as a steel band) on which the cassette sound absorber unit 10 or the cassette sound absorber assembly is fixed beforehand to form a preassembled unit, which is tightened around the wheel hub and around the rim outer surface to secure the preassembled unit. In order to form the preassembled unit, the cassette sound absorber unit 10 or the cassette sound absorber module is fitted with its cassette bottom surface and the carrier tape establishing surface and adhesively fixed to the carrier tape; alternatively, the cassette sound absorber unit 10 or the cassette sound absorber assembly is fixed to the carrier tape by fasteners (e.g., adhesive tape, clips, screws, etc.).

FIGS. 4A and 4B show the general configuration and internal construction of a single sound absorber unit, wherein the first embodiment of the sound absorber unit shown in FIG. 4A is provided with a groove in the top surface of the case, particularly adapted for assembly and securing with a strap according to the embodiment shown in FIGS. 2 and 3; the second embodiment of the sound absorber unit shown in fig. 4B is simple and neat in shape and convenient to manufacture and store. Fig. 4C exemplarily shows a general outer shape structure and an inner configuration of a sound absorber assembly in which two sound absorber units are combined.

Preferably, the cassette sound absorber unit 10 (see fig. 4A and 4B) or the cassette sound absorber assembly (see fig. 4C) is a rectangular parallelepiped-shaped box body integrally made of a plastic material, and may be manufactured by a 3D printing process.

As shown in particular in fig. 4A and 4B, the cassette-type sound absorber unit 10 has two sides bounding the two ends of the cassette in the circumferential direction of the wheel hub, one of the ends forming an open-end side 1 with an opening into the interior cavity of the cassette and the other end forming a closed-end side 1'. The cassette type sound absorber unit 10 forms a porous double-layer helmholtz resonance sound absorbing structure in which, the interior of the box body of the cassette sound absorber unit is divided by a partition 5 into a first cavity 4 and a second cavity 7 arranged one after the other in the circumferential direction of the wheel hub, two

hollow tubes

2, 3 whose orifices open into the wheel air chamber and which extend into the first cavity 4 at a distance corresponding to their tube length are formed on the open-end side 1, a nozzle of a hollow tube 6 is formed on the partition 5, the nozzle of the hollow tube opens into the first cavity 4 and the hollow tube extends into the second cavity 7 by a distance corresponding to the tube length, the first cavity 4 and the second cavity 7 constitute two layered resonant cavities of the porous double-layer helmholtz resonance sound absorbing structure. Here, the structural parameters of the case of the cassette type sound absorber unit 10, including the plate thickness of the partition plate 5 and the open-end side 1 and closed-end side 1', the orifice diameter and the tube length of each of the hollow tubes, and the shape, volume and wall thickness of the first cavity 4 and the second cavity 7, are determined by the predetermined sound absorption coefficient and the sound absorption amount of the porous double-layer helmholtz resonance sound absorbing structure. According to the present invention, it is advantageous that the cassette sound absorber unit 10 or the cassette sound absorber assembly itself forms a structural resonance sound absorber, as which the first order natural mode frequency coincides with the first order natural mode frequency of the wheel air chamber 30. This will be further explained below.

As shown in fig. 4C, the cassette type sound absorber module can be assembled by joining two of said cassette type sound absorber units 10 with their closed end sides 1'.

It is possible that a plurality of the cassette type sound absorber units 10 or the cassette type sound absorber modules are provided side by side on the hub 20 of the wheel, or a plurality of the cassette type sound absorber units 10 or the cassette type sound absorber modules are provided distributed along the circumference of the hub. The cassette sound absorber unit 10 or the cassette sound absorber assembly is in the mounted state with the bottom face of the cassette body abutting against the outer face of the rim of the hub 20.

As shown in fig. 5, it is expedient for this purpose for the cassette sound absorber unit 10 or the cassette sound absorber module to be provided with at least one bend extending transversely along its housing, which divides the cassette sound absorber unit or the cassette sound absorber module in the longitudinal direction of its housing into at least two sections in order, in the installed state, to conform the housing base to the circular-arc-shaped contour of the outer surface of the rim. For the cassette sound absorber unit, the bent portion 9' may be provided, for example, between the first chamber and the second chamber (see fig. 5); for the cassette-type sound absorber module, the bent portion 9 may be additionally provided at the attachment portion of the sound absorber unit, for example (see fig. 5). The bending part can be designed as a material weak part of the box body, can be continuous or discontinuous along the transverse direction of the box body, can transversely extend through the box body, and can also only extend on a part of the transverse section of the box body.

Specifically, fig. 4A and 4B show an embodiment of the sound absorber unit of the present invention, which is embodied as a box-shaped structure in a rectangular parallelepiped shape processed by injection molding. The interior of the box is divided into two cavities, namely a first cavity 4 and a second cavity 7, by a layer of thin plate (a partition plate 5), a side surface 1 (parallel to the interior of the box is divided into thin plates) of the box structure is provided with two pipe openings of

hollow pipes

2 and 3, and the interior of the box is divided into thin plates which are provided with a pipe opening of a hollow pipe 6. The plane of the orifice at one end of the two

hollow pipes

2 and 3 and the side surface 1 of the box-shaped structure are on the same plane, the pipe length extends into the first cavity 4, the plane of the orifice at one end of the hollow pipe 6 and the partition plate (partition plate 5) in the box are on the same plane, and the pipe length extends into the second cavity 7. The two

hollow tubes

2 and 3 of the resonance sound absorbing box structure shown in fig. 4A and 4B, which are installed on the circumferential surface of the circular arc of the hub 20 shown in fig. 1 to form a porous double-layered helmholtz resonance sound absorbing structure, communicate with the wheel air chamber (or tire air chamber) 30 shown in fig. 1.

Relevant parameters of the box structure having a rectangular parallelepiped shape shown in the drawing are determined using the sound absorption coefficient and the sound absorption amount of the double-layer helmholtz resonance sound absorbing structure, as described in the following equation:

z is the acoustic impedance of the resonant structure. Z_p1Acoustic impedance of the holes of the perforated structure of the first layer, Z_a1The acoustic impedance of the cavity of the first layer. Z_p2Acoustic impedance of the holes of the perforated structure of the second layer, Z_a2The acoustic impedance of the cavity of the second layer.

Where ρ is an air density, c is an air sound velocity, ω is 2 pi f, and f is a frequency. Gamma is air motion viscosity coefficient, gamma is 15 × 10^-6m²/s。t₁And t₂Thickness of the first and second layer, respectively, d₁And d₂The respective apertures of the first and second layers, δ₁And delta₂The perforation rates, D, of the first and second plies, respectively₁And D₂The thicknesses of the first layer and second layer cavities, respectively.

Z_rIs the relative specific acoustic impedance of the resonant structure.

Let R be Z_rThe real part of (A), X is Z_rthe sound absorption coefficient α of the resonance sound absorption structure is as follows:

sound absorption quantity calculation formula, A ═ as

Wherein: and A is the sound absorption quantity of the resonance sound absorption structure.

And S is the sum of the cross sectional areas of the hollow pipe 2 and the hollow pipe 3 of the resonance sound absorption structure.

The box-shaped structure with a cuboid shape is used as a resonance sound absorption structure, and the first-order natural modal frequency of the box-shaped structure is consistent with the first-order natural modal frequency of the wheel air chamber. The natural frequency of the steel plate reaches the design requirement through plate thickness and shape adjustment, and the adjustment mode of the steel plate needs to be realized through finite element calculation.

As an example, fig. 2 shows a first embodiment in which the sound absorber unit is arranged on the wheel hub. The sound absorbing porous double layer resonance structure shown in fig. 4A is designed with U-shaped grooves 8 on the upper surface thereof in order to mount the sound absorbing structure on the hub 20 shown in fig. 1. As shown in fig. 2, the installation method is as follows: the steel belt is used as a binding belt to pass through and be embedded into the U-shaped groove 8, and the resonance sound absorption structure is tightly pressed on the hub around the periphery of the hub to be fixed. The steel band may be fastened to the hub around its circumference by one or more sound-absorbing structures. The steel band junction is fastened with the buckle, and fastening force can show with fastening tool to judge the firm degree of installation.

As an example, fig. 3 shows a second embodiment in which the sound absorber unit is arranged on the wheel hub. In the application example shown in fig. 6, the natural frequency of the SUV vehicle, particularly the air chamber deformation geometry in the driving state, is calculated by using a commercial software, and for the natural frequency, the geometry and the sound absorption performance of the resonance sound absorption structure shown in fig. 4A or fig. 4B are designed and adjusted according to the formula (1) and the formula (2). Because the inherent structure mode of a single resonance sound absorption structure is higher, in order to enable the structure mode of the resonance sound absorption structure to be consistent with the inherent mode of a tire air chamber and achieve the purpose of structure resonance noise reduction, two resonance sound absorption structures (namely the sound absorber unit 10) are connected together at the closed end, and the geometric dimension of the inherent frequency of the whole connected structure is adjusted by a numerical simulation means, so that the design of the resonance sound absorption structure is completed. In this case, a plastic material is used to fabricate a resonant sound absorption structure object ("sound absorber unit" or "sound absorber assembly") by 3D printing, and two sound absorber units are combined together as shown in fig. 5 to form a sound absorber assembly (that is, a pair of sound absorber units forms a sound absorber assembly). Two sound absorber assemblies (i.e., two pairs of sound absorber units in total) are mounted on the rim surface, and the two sound absorber assemblies are symmetrically mounted on the rim surface, as shown in fig. 7. It is possible to pre-fix the two sound absorber modules to the tie-down element to form a pre-assembled unit (in which case the tie-down element acts as a carrier band, for example steel strips may be used) and then to assemble and fix the pre-assembled unit to the wheel hub.

The SUV is taken as a tested vehicle, road surface working condition driving is executed under the vehicle speeds of 15km/h and 30km/h under the three conditions that the wheels of the SUV are not provided with a resonance sound absorption structure, the resonance sound absorption structure is arranged according to the prior art and the resonance sound absorption structure is arranged according to the invention, actual measurement and comparison of noise characteristics in the SUV are carried out, and the measuring point is positioned at a co-driver position. FIG. 8 is a graph showing the spectrum of the noise level measured in the vehicle under the condition that the wheels of the vehicle are not provided with the resonance sound absorption structure, the vehicle is provided with the resonance sound absorption structure according to the prior art and the vehicle is provided with the resonance sound absorption structure according to the invention in the road running test at the vehicle speed of 15 km/h. FIG. 9 is a graph showing the spectrum of the noise level measured in the vehicle under the condition that the wheels of the vehicle are not provided with the resonance sound-absorbing structure, the vehicle is provided with the resonance sound-absorbing structure according to the prior art and the vehicle is provided with the resonance sound-absorbing structure according to the present invention in the road running test at the vehicle speed of 30 km/h. Here, the process is repeated. Each of the four wheels is provided with two pairs of the resonance sound absorption structures (see fig. 7), for a total of eight pairs. And carrying out real vehicle test on a rough road surface. In fig. 8 and 9, a line "III" is a spectrum of the noise level in the vehicle when the tested vehicle is not equipped with the resonance sound absorbing structure, a line "II" is a spectrum of the noise level in the vehicle when the resonance sound absorbing structure of the present invention is installed, and a line "I" is a spectrum of the noise level in the vehicle when the resonance sound absorbing structure of the prior art is installed (for comparative reference only). As can be seen from the figure, the peak value of the noise generated by the resonance of the tire air chamber in the vehicle is prominent near 200Hz, and after the resonance sound absorption structure is installed, the peak value is greatly reduced, the maximum value is about 8dB (A), and the noise generated by the resonance of the tire air chamber is effectively reduced.

The foregoing detailed description of the embodiments of the present application has been presented to illustrate the principles and implementations of the present application, and the above description of the embodiments is only provided to help understand the core concepts of the present application; meanwhile, for those skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims

1. A wheel with sound absorption means mounted inside the wheel air chamber (30) for reducing acoustic resonances, characterized in that the sound absorption means comprise at least one integrally formed cassette sound absorber unit (10) or at least one cassette sound absorber assembly composed of a plurality of sound absorber units into a single body, said cassette sound absorber unit or said cassette sound absorber assembly being bound to the hub (20) of the wheel by means of a binding element (50).

2. A wheel according to claim 1, characterized in that said cassette sound absorber unit (10) or said cassette sound absorber assembly is a parallelepiped-shaped box made in one piece of metal material or plastic material.

3. A wheel according to claim 1, characterized in that said cartridge-type sound absorber unit (10) or said cartridge-type sound absorber assembly is a cuboid-shaped box made by a 3D printing process.

4. A wheel according to claim 1, characterized in that the cassette-type sound absorber unit (10) has two sides bounding the two ends of the cassette in the circumferential direction of the wheel hub, wherein one end forms an open-ended side (1) with an opening into the interior cavity of the cassette and the other end forms a closed-ended side (1').

5. A wheel according to claim 4, wherein the cassette-type sound absorber unit (10) forms a porous double-layer Helmholtz resonance sound absorbing structure, wherein the interior of the cassette-type sound absorber unit is divided by a partition wall (5) into a first cavity (4) and a second cavity (7) arranged one after the other in the circumferential direction of the wheel hub, wherein two tubular openings (2, 3) are formed in the open-end side (1), wherein the tubular openings of the two hollow tubes are open to the wheel air chamber and extend into the first cavity (4) at a distance corresponding to the tube length thereof, wherein a tubular opening of a hollow tube (6) is formed in the partition wall (5), wherein the tubular opening of the one hollow tube is open to the first cavity (4) and wherein the one hollow tube extends into the second cavity (7) at a distance corresponding to the tube length thereof, the first cavity (4) and the second cavity (7) form two layered resonant cavities of the porous double-layer Helmholtz resonance sound absorption structure.

6. A wheel according to claim 5, characterized in that the structural parameters of the box of said box-type sound absorber unit (10), including the plate thickness of said partition plate (5) and of said open-end side (1) and closed-end side (1'), the orifice diameter and the tube length of each of said hollow tubes, the shape, volume and wall thickness of said first (4) and second (7) cavities, are determined by the predetermined sound absorption coefficient and sound absorption capacity of said porous double-layer Helmholtz resonance sound absorbing structure.

7. A wheel according to claim 4, characterized in that said cassette-type sound absorber assembly is composed of two said cassette-type sound absorber units (10) joined with their closed end sides (1').

8. A wheel according to any of claims 1 to 7, wherein said cassette sound absorber unit (10) or said cassette sound absorber assembly itself forms a structural resonance sound absorber as the first order natural modal frequency of which coincides with the first order natural modal frequency of the wheel air chamber (30).

9. A wheel according to any of claims 1 to 7, wherein a plurality of said cassette sound absorber units (10) or said cassette sound absorber assemblies are arranged side by side on the hub (20) of the wheel or a plurality of said cassette sound absorber units (10) or said cassette sound absorber assemblies are arranged distributed along the circumference of the hub.

10. A wheel according to any of claims 1 to 7, characterized in that the cassette sound absorber unit (10) or the cassette sound absorber assembly in the mounted state rests with the bottom surface of the cassette against the outer rim surface of the hub (20).

11. A wheel according to claim 10, wherein said cassette sound absorber unit (10) or said cassette sound absorber assembly is provided with at least one bend (9, 9') extending transversely of its cassette body, said bend dividing the cassette sound absorber unit or said cassette sound absorber assembly in its cassette body longitudinal direction into at least two sections for conforming the cassette body bottom surface to the circular arc shaped contour of the rim outer surface in the mounted state.

12. A wheel according to any of claims 1 to 7, characterized in that said tie element (50) is a tie strap which is pressed from the top face of the box of the cartridge sound absorber unit (10) or assembly against the outer face of the wheel hub rim and tightens said cartridge sound absorber unit (10) or assembly around the hub (20), the two ends of the tie strap being fixedly connected by snapping, the tightening force of the tie strap being settable and/or displayable by means of a tightening tool.

13. A wheel according to claim 12, characterized in that said cassette sound absorber unit (10) or said cassette sound absorber assembly is provided with a U-shaped groove (8) for embedding said strap on the top surface of its case.

14. A wheel according to any of claims 1 to 7, wherein the restraining element (50) is a carrier tape to which the cartridge absorber unit (10) or assembly is pre-secured to form a pre-assembled unit, the carrier tape being tightened around the hub and around the outer surface of the rim to secure the pre-assembled unit.

15. A wheel according to claim 14, wherein said cassette sound absorber unit (10) or cassette sound absorber assembly is fitted with its cassette bottom face to said carrier strip establishing face and adhesively fixed to said carrier strip.

16. A wheel according to claim 14, wherein said cassette sound absorber unit (10) or cassette sound absorber assembly is fixed to said carrier strip by fasteners.