Low-noise pocket wheel covers

Abstract

The present invention provides a low-noise pocket-type wheel cover, comprising a protective cover mounted to face a surface of a vehicle tire, wherein a noise reduction pocket is formed within the protective cover so as to protrude toward the interior of the vehicle. Since the noise reduction pocket is formed at an end of the wheel cover where a sound field due to tire tread noise is expected to be generated, the sound field due to the tire tread noise is interfered with and prevented from being generated.

Description

Technical Field

[0001] The present invention relates to a low-noise pocket wheel cover, and more particularly to a low-noise pocket wheel cover capable of effectively removing peak noise generated by tire tread components and deteriorating running noise in a vehicle. Background Art

[0002] Wheel covers are installed on vehicles to enhance the appearance by covering the vehicle body and to prevent the tires from contaminating the vehicle body. At the same time, studies have shown that when a vehicle is running, tire pattern noise is generated in the frequency range of 800Hz to 1200Hz.

[0003] Meanwhile, studies have shown that tire tread noise is generated in the frequency range of 800 Hz to 1200 Hz when a vehicle is running (SW Hwang, MJ Bang, GHR Ho, and CTC Ho, "Study on Tire Tread Noise," Proceedings of the Spring Meeting of the Korean Society of Noise and Vibration Engineering, pp. 310-313, 2006).

[0004] Due to the peak noise characteristics, the tire pattern noise is recognized by the user in the vehicle. In addition, the acoustic constructive interference phenomenon of the tire pattern noise occurs according to the distance between the tire surface and the wheel cover, which worsens the running noise heard in the vehicle.

[0005] Figure 1 FIG is a diagram showing driving noise detected in a vehicle with a wheel cover installed and a vehicle without a wheel cover installed according to the related art. Figure 1 As shown, when the wheel cover is installed, the peak point of the driving noise detected in the vehicle is measured to be higher. When the wheel cover is installed, the vibration corresponding to the frequency of the peak point of the tire pattern noise is concentrated on a specific part of the wheel cover, forming a sound field.

[0006] Figure 2 The results of analyzing the sound field of the wheel cover according to the related art are shown. Figure 2 As shown, a strong sound field is concentrated at the wheel housing end at the tire tread noise frequency (e.g., from 800Hz to 1200Hz). Therefore, it can be inferred that vibrations at the frequency corresponding to the tire tread noise peak create a sound field in the wheel housing, amplifying the tire tread noise peak. Furthermore, since the amplified tire tread noise peak is introduced into the vehicle interior, the driving noise detected inside the vehicle deteriorates. Summary of the Invention

[0007] The present invention provides a low-noise pocket wheel cover that effectively removes peak noise, which is a component of tire tread patterns and degrades the driving noise detected within a vehicle. Other objects and advantages of the present invention will be understood from the following description and will become apparent with reference to the embodiments of the present invention. Furthermore, it will be apparent to those skilled in the art that the objects and advantages of the present invention can be achieved by the claimed apparatus and combinations thereof.

[0008] According to an exemplary embodiment of the present invention, a low-noise pocket wheel cover may include a protective cover mounted to face a surface of a tire in a vehicle, wherein a noise reduction pocket may be formed in the protective cover so as to protrude toward the interior of the vehicle. Furthermore, the protective cover may be arc-shaped, and the noise reduction pocket may include an inlet formed on the inner surface of the protective cover and a space protruding from the inlet toward the outside of the protective cover.

[0009] The inlet may be provided on one side of the ends of the protective cover facing the rear of the vehicle. The protective cover may be arc-shaped, and the noise reduction pocket may include: a first pocket provided on one side of the ends of the protective cover facing the rear of the vehicle; and a second pocket formed closer to the center portion of the protective cover than the first pocket.

[0010] The wavelength tube principle can be applied to calculate the height of the space perpendicular to an imaginary line parallel to the ground and in the same direction as the vehicle's travel direction. The height of the space can be calculated using the following formula 1:

[0011] Formula 1

[0012] h=(1 / 4)×(c / f),

[0013] Wherein, h represents the height of the space, c represents the speed of sound (about 340m / s), and f represents the target frequency (in the range of about 700Hz to 1400Hz).

[0014] The expansion tube principle can be applied to calculate the length of the inlet perpendicular to an imaginary line parallel to the ground. The length of the inlet can be calculated using the following formula 2:

[0015] Formula 2

[0016] a=(1 / 2)×(c / f)=2×h,

[0017] Wherein, a represents the length of the inlet, c represents the speed of sound (approximately 340 m / s), f represents the target frequency (in the range of approximately 700 Hz to 1400 Hz), and h represents the height of the space 220 .

[0018] In addition, the noise reduction pocket can be formed as two or more noise reduction pockets, arranged from one side of the rear end of the vehicle at both ends of the protective cover toward the center part of the protective cover; and because the two or more noise reduction pockets are formed closer to the center part of the protective cover, the target frequency substituted into the calculation of the length of the entrance and the height of the space can be set to be smaller.

[0019] In addition, the height of the space may include: a first height corresponding to the size of the edge of the lower surface of the space closest to the ground; and a second height corresponding to the size of the edge of the upper surface of the space farther from the ground than the lower surface of the space, the target frequencies substituted into the calculation of the first height and the second height may be different from each other, and the smaller target frequency of the target frequencies substituted into the calculation of the first height and the second height may be substituted into the calculation of the length of the entrance.

[0020] The entrance length perpendicular to an imaginary line parallel to the ground can be determined in the range of approximately 12 cm to 24 cm, and the height of the space perpendicular to an imaginary line parallel to the ground and in the same direction as the vehicle's travel can be determined in the range of approximately 6 cm to 12 cm. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and other features of the present invention will now be described in detail with reference to exemplary embodiments of the invention shown in the accompanying drawings which are given hereinafter by way of illustration only and are therefore non-limiting, and in which:

[0022] Figure 1 A diagram showing driving noise at a front seat detected in the interior of a vehicle with a wheel cover installed and a vehicle without a wheel cover installed according to the related art;

[0023] Figure 2 A diagram showing a result of analyzing a sound field of a wheel cover according to the related art;

[0024] Figure 3 A perspective view showing a low-noise pocket wheel cover according to an exemplary embodiment of the present invention;

[0025] Figures 4 to 6 To illustrate an exemplary embodiment of the present invention Figure 3 A cross-sectional view of the main part of the low-noise pocket wheel cover;

[0026] Figure 7 A cross-sectional view illustrating an inlet length and a space height according to an exemplary embodiment of the present invention;

[0027] Figure 8 is a diagram of setting a target frequency according to an exemplary embodiment of the present invention;

[0028] Figure 9A diagram showing a result of measuring noise in a front-rear direction of a wheel house according to an exemplary embodiment of the present invention;

[0029] Figure 10 is a diagram illustrating running noise detected in a vehicle according to an exemplary embodiment of the present invention;

[0030] Figure 11 A schematic diagram illustrating the wavelength tube principle according to an exemplary embodiment of the present invention; and

[0031] Figure 12 Schematic diagram illustrating the principle of an expansion tube according to an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0032] It should be understood that the term "vehicle" or "vehicular" or other similar terms used herein generally include motor vehicles, such as passenger vehicles including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, ships including various boats, vessels, aircraft, etc., and include hybrid vehicles, electric vehicles, combustion engine vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g., fuels derived from non-fossil energy sources).

[0033] Although the exemplary embodiments are described as utilizing multiple units to perform the exemplary processes, it should be understood that the exemplary processes may also be performed by one or more modules. Furthermore, it should be understood that the term controller / control unit refers to a hardware device that includes a memory and a processor. The memory is configured to store the modules, and the processor is specifically configured to execute the modules to perform one or more processes described further below.

[0034] The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "one", "an" and "the" used herein are intended to also include plural forms, unless the context clearly indicates other situations. It should be further understood that, when used in this specification, the terms "include" and / or "comprise" specify the features, numerical values, steps, operations, elements, and / or components of the present statements, but do not exclude the presence or increase of one or more other features, numerical values, steps, operations, elements, components, and / or their combinations. The terms "and / or" used herein include any and all combinations of one or more associated listed items.

[0035] Unless specifically stated or obvious from the context, the term "about" as used herein is understood to mean within a normal tolerance range in the art, such as within 2 standard deviations of the mean. "About" can be understood to mean within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the stated value. Unless otherwise clear from the context, all numerical values provided herein are modified by the term "about."

[0036] Hereinafter, a low-noise pocket type wheel cover according to an exemplary embodiment of the present invention will be described with reference to the accompanying drawings.

[0037] like Figures 3 to 7 As shown, a low-noise pocket type wheel cover according to an exemplary embodiment of the present invention may include a protective cover 100 mounted on a surface T facing a tire in a vehicle and a noise reduction pocket 200 formed in the protective cover 100 to protrude toward an interior of the vehicle. Figure 3 The protective cover 100 shown can be manufactured in an arc shape. In addition, the protective cover 100 can be manufactured so that the diameter based on the center point of the tire is larger than the diameter of the tire. The protective cover 100 can be made of iron material. A guide device for increasing air flow can be formed in the protective cover 100.

[0038] like Figures 4 to 7 As shown, it can be assumed that the distance d between the protective cover 100 and the surface T of the tire is in the range of about 6 centimeters (cm) to 12 centimeters (cm). The noise reduction pocket 200 may include an inlet 210 and a space 220, wherein the inlet 210 is formed on the inner surface of the protective cover 100 and has a length a, and the space 220 is formed to protrude to the outside of the protective cover 100 and has the length a of the inlet 210. The inlet 210 may be formed in a portion of the surface of the protective cover 100 where a sound field of a vibration frequency corresponding to a peak point of tire pattern noise is formed. The inlet 210 may be formed so that the length a is 1 / 2 wavelength of the vibration frequency of the peak point. The space 220 may be formed so that the height h is 1 / 4 wavelength of the vibration frequency of the peak point. The 1 / 4 wavelength can be obtained by dividing the speed of sound by the vibration frequency.

[0039] When the tire pattern noise moves along the protective cover 100, the wavelength corresponding to the peak point oscillates toward the space 220, thereby preventing the formation of a sound field. In addition, since the formation of a sound field in the protective cover 100 can be prevented, the tire pattern noise is not amplified by the sound field.

[0040] like Figure 2 As shown, the inlet 210 may be arranged on one side of the end portion at the rear of the vehicle at both ends of the protective cover 100. Figure 9As shown, the vibration frequency corresponding to the peak point of the tire pattern noise on the side of the ends of the protective cover 100 in front of the vehicle is not amplified by the protective cover 100. Therefore, the noise reduction pockets 200 do not need to be formed on the ends of the protective cover 100 in front of the vehicle.

[0041] like Figure 5 As shown, the noise reduction pocket 200 may include a first pocket 201 provided on one side of the end portion of the protective cover 100 at the rear of the vehicle, and a second pocket 202 formed outside the first pocket 201 near the center portion of the protective cover 100. Since two or more noise reduction pockets 200 are formed in the protective cover 100, it is possible to prevent the formation of sound fields of different frequencies (see FIG. Figure 8 ).

[0042] like Figure 6 As shown, the inner wall surface of the space 220 facing the rear side of the vehicle can be formed into an inclined shape. Figure 7 , the length a of the entrance 210 perpendicular to an imaginary line parallel to the ground can be determined within a range of approximately 12 cm to 24 cm. The height h of the space 220 perpendicular to an imaginary line parallel to the ground and in the same direction as the vehicle's travel direction can be determined within a range of approximately 6 cm to 12 cm. Figure 7 In the figure, the dotted line represents the waveform of tire noise propagation.

[0043] In addition, the wavelength tube principle (in which the sound waves reflected from the far end of the pipe are reversed at the inlet end to control the noise at the inlet end) can be used to control the noise at the inlet end. Figure 11 )) and the expansion pipe principle (reducing the noise transmission sensitivity by suddenly changing the area of the pipe or pipeline (see Figure 12 )) Calculate the length a of the entrance 210 and the height h of the space 220. The height h of the space 220 perpendicular to an imaginary line parallel to the ground and in the same direction as the vehicle's travel direction can be calculated using the following formula 1.

[0044] Formula 1

[0045] h=(1 / 4)×(c / f)

[0046] Here, h represents the height of the space 220, c represents the speed of sound (approximately 340 m / s), and f represents the target frequency (in the range of approximately 700 Hz to 1400 Hz).

[0047] In addition, the length a of the inlet 210 perpendicular to an imaginary line parallel to the ground can be calculated by the following Formula 2.

[0048] Formula 2

[0049] a=(1 / 2)×(c / f)=2×h

[0050] Wherein, a represents the length of the inlet 210 , c represents the speed of sound (approximately 340 m / s), f represents the target frequency (in the range of approximately 700 Hz to 1400 Hz), and h represents the height of the space 220 .

[0051] like Figure 5 As shown, when two or more noise reduction pockets 200 are formed to be arranged from one side of the end portion at the rear of the vehicle at both ends of the protective cover 100 toward the central portion of the protective cover 100, because the two or more noise reduction pockets 200 are formed closer to the central portion of the protective cover 100, the target frequency substituted into the calculation of the length a of the entrance 210 and the height h of the space 220 can be set to be smaller or reduced (compared to when one noise reduction pocket is provided).

[0052] like Figure 6 As shown, when the inner wall of noise reduction pocket 200 is tilted toward the rear of the vehicle, the target frequency can be set as follows. Within the height h of space 220, the dimension of the edge of the lower surface of space 220 closest to the ground is referred to as first height h1, and the dimension of the edge of the upper surface of space 220 farther from the ground than the lower surface of space 220 is referred to as second height h2. Different target frequencies can be substituted into the calculation of first height h1 and second height h2. Furthermore, the smaller target frequency among the target frequencies substituted into the calculation of first height h1 and second height h2 can be substituted into the calculation of length a of inlet 210.

[0053] As described above, according to the low-noise pocket wheel cover according to an exemplary embodiment of the present invention, the noise reduction pocket 200 can be formed at the end of the wheel cover where a sound field due to tire pattern noise is expected to be formed, which can interfere with and prevent the formation of a sound field due to tire pattern noise.

[0054] like Figure 10 As shown, when an exemplary embodiment of the present invention is applied, the peak point in the target frequency range is measured to be lower than the peak point when an exemplary embodiment of the present invention is not applied. Figure 10 It is shown that the peak noise of the tire pattern component that deteriorates the running noise detected inside the vehicle can be effectively removed.

[0055] According to the low-noise pocket wheel cover described above, according to an exemplary embodiment of the present invention, the noise reduction pocket can be formed at the end of the wheel cover where the sound field due to tire tread noise is expected to form, thereby interfering with and preventing the formation of a sound field due to the tire tread noise. As a result, the peak noise of the tire tread component that worsens the driving noise detected inside the vehicle can be effectively removed.

[0056] Although the present invention has been described with respect to specific exemplary embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present invention as defined by the appended claims. Therefore, it should be noted that such changes or modifications fall within the scope of the claims of the present invention and should be interpreted based on the appended claims.

Claims

1. A low-noise pocket wheel cover, comprising: A protective cover mounted to face the surface of the vehicle tire, wherein a noise reduction pocket is formed in the protective cover so as to protrude toward the interior of the vehicle; Wherein, the noise reduction pocket includes: an inlet formed on an inner surface of the protective cover; and a space that protrudes from the entrance toward the outside of the protective cover; wherein the inlet is formed at a portion of the surface of the protective cover that forms a sound field having a vibration frequency corresponding to a peak point of the tire tread noise, thereby preventing the formation of the sound field and preventing amplification of the tire tread noise caused by the sound field; The noise reduction pocket includes a first pocket and a second pocket, wherein the first pocket is provided on one side of the ends of the protective cover at the rear of the vehicle, and the second pocket is formed closer to the center of the protective cover than the first pocket, thereby preventing the formation of sound fields of different frequencies; The height of the space is calculated by the following formula 1: Formula 1: h=(1 / 4)×(c / f), Where h represents the height of the space, c represents the speed of sound, and f represents the target frequency; wherein a target frequency substituted into the calculation of the length of the entrance and the height of the space is set to be smaller or reduced compared to when a noise reduction pocket is provided; The length of the inlet is calculated by the following formula 2: Formula 2: a=(1 / 2)×(c / f)=2×h, Where a represents the length of the entrance, c represents the speed of sound, f represents the target frequency, and h represents the height of the space; Among them, when the inner wall of the noise reduction pocket is inclined toward the rear side of the vehicle, the height of the space includes: a first height corresponding to a dimension of an edge of a lower surface of the space closest to the ground; and a second height corresponding to the dimension of the edge of the upper surface of the space that is further from the ground than the lower surface of the space, and wherein the target frequencies substituted into the calculations of the first height and the second height are different from each other, and Among the target frequencies substituted into the calculation of the first height and the second height, the minimum target frequency is substituted into the calculation of the length of the entry.

2. The low-noise pocket wheel cover according to claim 1, wherein: The inlet is provided on one side of the end portion of the protective cover at the rear of the vehicle.

3. The low-noise pocket wheel cover according to claim 1, wherein: The protective cover is curved.

4. The low-noise pocket wheel cover according to claim 1, wherein: The wavelength tube principle is applied to calculate the height of the space parallel to an imaginary line parallel to the ground and in the same direction as the vehicle's travel direction.

5. The low-noise pocket wheel cover according to claim 1, wherein: Apply the expansion tube principle to calculate the length of the inlet perpendicular to an imaginary line parallel to the ground.

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