Sound deadening structure and vehicle

Abstract

To provide a muffling structure with a simpler structure.SOLUTION: A muffling structure 1 includes a frame 31 positioned between right and left vents 40. The frame 31 includes: two resonator chambers 50 and 51; and two communication pipes 60 and 61 communicated from the right and left vents 40 to the resonator chambers 50 and 51 corresponding to the vents. The two resonator chambers 50 and 51 are arranged side by side in a ventilation direction of the vents 40. The communication pipes 60 and 61 are formed by using a part of side walls of the resonator chambers 50 and 51.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a sound deadening structure and a vehicle. [Background technology]

[0002] Patent Document 1 discloses a gas turbine combustor for aircraft that uses a Helmholtz resonator (resonator) (see Patent Document 1). Also, Cited Document 2 discloses a variable frequency silencing system that uses a variable resonator for use in automobile engines (see Patent Document 2). Devices that generate noise like this require a silencing device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 071399 [Patent Document 2] JP 2007-205327 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional noise reduction system as described above requires adding a new resonator to existing devices and components, and has a complex configuration and is expensive.

[0005] The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a sound deadening structure having a simpler structure. [Means for solving the problem]

[0006] A sound-absorbing structure according to one embodiment of the present invention comprises a frame located between left and right air vents, the frame having a plurality of resonator chambers and a plurality of communicating pipes connecting each of the left and right air vents to the corresponding resonator chamber.

[0007] According to the above aspect, by using the frame of the vent hole, a sound deadening structure with a simpler structure can be realized.

[0008] In the above aspect, the multiple resonator chambers may be arranged side by side in the direction in which the ventilation opening passes.

[0009] In the above aspect, the communication pipe may be formed using a part of a side wall of the resonator chamber.

[0010] In the above aspect, the communication pipe may be formed between adjacent resonator chambers.

[0011] In the above aspect, the plurality of resonator chambers and the plurality of communicating pipes may be formed so as to target sound of a single frequency for noise reduction.

[0012] In the above aspect, the plurality of resonator chambers and the plurality of communicating pipes may be formed so as to target sounds of a plurality of frequencies to be silenced.

[0013] In the above aspect, at least one of the plurality of resonator chambers may be provided with a sound absorbing material.

[0014] In the above aspect, the frame may have an elongated shape that is long in a direction perpendicular to the air flow direction of the air vent, and the multiple resonator chambers and the multiple communicating pipes may extend along the longitudinal direction of the frame.

[0015] In the above aspect, a plurality of the ventilation openings may be arranged in one direction, and the frames may be provided between adjacent left and right ventilation openings.

[0016] A vehicle according to another aspect of the invention includes the above-described sound deadening structure. Effect of the Invention

[0017] The present invention can provide a sound deadening structure with a simpler structure. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a diagram showing an outline of a cowl louver of a vehicle; [Diagram 2] FIG. [Diagram 3] FIG. 4 is an enlarged view of a portion of the outside air introduction section. [Figure 4] FIG. 2 is an explanatory diagram showing a frame configuration. [Diagram 5] FIG. 2 is a cross-sectional view of the frame viewed in the longitudinal direction. [Figure 6] 13 is a schematic diagram showing the sound deadening effect of sound passing through ventilation holes between multiple frames. FIG. [Figure 7] FIG. 2 is a cross-sectional view of a frame having sound-deadening material. [Figure 8] 10A to 10C are explanatory diagrams for explaining the sound deadening effects of various frames. [Figure 9] A cross-sectional view of a frame having two resonator chambers with different volumes. [Figure 10] FIG. 13 is a cross-sectional view of a frame in which the passage areas of two communicating pipes are different. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described in detail. Note that, unless otherwise specified, the positional relationships such as up, down, left, and right in the drawings are based on the positional relationships shown in the drawings.

[0020] Fig. 1 is a perspective view showing a cowl louver 10 of a vehicle having a sound deadening structure 1 according to the present embodiment, and Fig. 2 is a perspective view showing an outside air introduction section 20 of the cowl louver 10. Fig. 3 is an enlarged view of a portion of the outside air introduction section 20.

[0021] 1 is disposed between a windshield glass of a vehicle and an engine hood (bonnet) that covers the top surface of an engine room. The cowl louvers 10 have an outside air intake section 20 for taking outside air into the vehicle interior.

[0022] As shown in FIGS. 2 and 3, the outside air introduction section 20 has, for example, a substantially rectangular frame 30, a plurality of frames 31 arranged inside the frame 30, and a reinforcing frame 32.

[0023] The frames 31 have an elongated shape extending in the short side direction X of the frame 30. A plurality of the frames 31 are arranged in a line along the long side direction Y of the frame 30. The frames 31 are provided at equal intervals from each other along the long side direction Y of the frame 30. Slit-shaped ventilation holes 40 are formed between adjacent frames 31, i.e., on both the left and right sides of each frame 31. In the outside air introduction section 20, a plurality of ventilation holes 40 are arranged in a line along the long side direction Y of the frame 30.

[0024] The reinforcing frames 32 connect, for example, adjacent frames 31 to each other, and connect the frames 31 at the ends in the long side direction Y to the frame 30. The number of reinforcing frames 32 is not particularly limited, and multiple reinforcing frames 32 may be provided along the frame 31. Also, the reinforcing frames 32 may not be present.

[0025] The outside air introduction section 20 has a sound deadening structure 1 in this embodiment. The sound deadening structure 1 is provided on a frame 31. Fig. 4 is an explanatory diagram showing the configuration of the frame 31, and Fig. 5 is a cross-sectional view (viewing the frame 31 along the longitudinal direction X) perpendicular to the longitudinal direction X of the frame 31 (the direction of the short side of the frame 30).

[0026] The frame 31 is hollow inside and has two resonator chambers 50, 51 and two communication pipes 60, 61 that communicate from each of the left and right ventilation holes 40 to either of the resonator chambers 50, 51. In Figs. 4 and 5, the upper resonator chamber is the upper resonator chamber 50, and the lower resonator chamber is the lower resonator chamber 51. In this specification, "upper" and "lower" are based on the positions of the frame 31 in Figs. 4 and 5. In this embodiment, the upper side is the upstream side of the ventilation hole 40, and the lower side is the downstream side of the ventilation hole 40.

[0027] The upper resonator chamber 50 is formed across both ends of the frame 31 along the longitudinal direction X of the frame 31 as shown in Fig. 4. As shown in Fig. 4 and Fig. 5, the upper resonator chamber 50 has a substantially semicircular cross-sectional shape in a cross section perpendicular to the longitudinal direction X. The upper resonator chamber 50 has, for example, a first side wall portion 70, a second side wall portion 71, and a third side wall portion 72.

[0028] The first side wall portion 70 is located on the top surface of the upper resonator chamber 50. The first side wall portion 70 is long in the longitudinal direction X of the frame 31, and is formed in a substantially semicircular arc shape that is convex upward in a cross section of the frame 31 seen from the longitudinal direction X.

[0029] The second side wall portion 71 is located on the bottom surface of the upper resonator chamber 50. The second side wall portion 71 is elongated in the longitudinal direction X of the frame 31, and has a flat plate shape with the plate surface facing the up-down direction Z. A first end portion 71a of the second side wall portion 71 is connected to a first end portion 70a of the first side wall portion 70 in the left-right direction (long side direction of the frame 30) Y.

[0030] The third side wall portion 72 is located on the bottom surface of the upper resonator chamber 50. The third side wall portion 72 is elongated in the longitudinal direction X of the frame 31, and has a flat plate shape with the plate surface facing the up-down direction Z. A first end portion 72a of the third side wall portion 72 is connected to a second end portion 70b of the first side wall portion 70 in the left-right direction Y. The second side wall portion 71 and the third side wall portion 72 are not connected to each other, and an opening A1 is formed therebetween.

[0031] The lower resonator chamber 51 is formed across both ends of the frame 31 along the longitudinal direction X of the frame 31. The lower resonator chamber 51 has a substantially rectangular cross-sectional shape in a cross section perpendicular to the longitudinal direction X. The lower resonator chamber 51 has, for example, a first side wall portion 90, a second side wall portion 91, a third side wall portion 92, a fourth side wall portion 93, and a fifth side wall portion 94.

[0032] The first side wall portion 90 and the second side wall portion 91 are located on the ceiling surface of the lower resonator chamber 51. The first side wall portion 90 and the second side wall portion 91 are elongated in the longitudinal direction X of the frame 31 and have a flat plate shape with the plate surface facing the up-down direction Z. The first side wall portion 90 is provided at a position facing the second side wall portion 71 of the upper resonator chamber 50. The second side wall portion 91 is provided at a position facing the third side wall portion 72 of the upper resonator chamber 50. The first side wall portion 90 and the second side wall portion 91 are not connected to each other, and an opening A2 is formed therebetween.

[0033] The third side wall portion 92 is located on the bottom surface of the lower resonator chamber 51. The third side wall portion 92 has a flat plate shape that is long in the longitudinal direction X and has a plate surface facing in the up-down direction Z.

[0034] The fourth side wall portion 93 is located on the left and right side surfaces of the lower resonator chamber 51. The fourth side wall portion 93 is elongated in the longitudinal direction X and has a flat plate shape with the plate surface facing the left-right direction Y. Both upper and lower ends of the fourth side wall portion 93 are connected to a first end portion 92a of the third side wall portion 92 and a first end portion 90a of the first side wall portion 90.

[0035] The fifth side wall portion 94 faces the fourth side wall portion 93 and is located on the left and right side surfaces of the lower resonator chamber 51. The fifth side wall portion 94 is elongated in the longitudinal direction X and has a flat plate shape with its plate surface facing the left-right direction Y. Both upper and lower ends of the fifth side wall portion 94 are connected to the second end portion 92b of the third side wall portion 92 and the first end portion 91a of the second side wall portion 91.

[0036] Furthermore, the second end 72b of the third side wall portion 72 of the upper resonator chamber 50 and the second end 90b of the first side wall portion 90 of the lower resonator chamber 51 are connected by a partition wall 100. The partition wall 100 has a plate shape that is long in the longitudinal direction X and is inclined downward from the third side wall portion 72 toward the first side wall portion 90. The partition wall 100 separates a space B1 surrounded by the second side wall portion 71 of the upper resonator chamber 50 and the first side wall portion 90 of the lower resonator chamber 51 from a space B2 surrounded by the third side wall portion 72 of the upper resonator chamber 50 and the second side wall portion 91 of the lower resonator chamber 51.

[0037] The communication pipe 60 communicates with the upper resonator chamber 50. The communication pipe 60 is formed across both ends of the frame 31 along the longitudinal direction X of the frame 31. The communication pipe 60 opens into the vent hole 40 on one side of the left-right direction Y of the frame 31 (the left side in Figs. 4 and 5). The communication pipe 60 is provided near the center of the frame 31 in the up-down direction Z. The communication pipe 60 is formed by the second side wall portion 71 of the upper resonator chamber 50, the first side wall portion 90 of the lower resonator chamber 51, and the partition wall 100, and leads from the opening A3 of the vent hole 40 through the space B1 between the upper resonator chamber 50 and the lower resonator chamber 51 to the opening A1.

[0038] The communication pipe 61 communicates with the lower resonator chamber 51. The communication pipe 61 is formed across both ends of the frame 31 along the longitudinal direction X of the frame 31. The communication pipe 61 opens into the vent hole 40 on one side of the left-right direction Y of the frame 31 (the right side in Figs. 4 and 5). The communication pipe 61 is provided near the center of the frame 31 in the up-down direction Z. The communication pipe 61 is formed by the third side wall portion 72 of the upper resonator chamber 50, the second side wall portion 91 of the lower resonator chamber 51, and the partition wall 100, and leads from the opening A4 of the vent hole 40 through the space B2 between the upper resonator chamber 50 and the lower resonator chamber 51 to the opening A2.

[0039] The sound deadening structure 1 uses a resonance effect to attenuate sound of a predetermined frequency f passing through the ventilation opening 40. The frequency f of sound attenuated by the frame 31 is expressed by the following formula 1.

[0040]

number

[0041] The upper resonator chamber 50 attenuates sound of frequency f1 obtained by substituting the volume V1 of the upper resonator chamber 50, the length L1 of the communicating pipe 60, and the passage area S1 of the communicating pipe 60 into Equation 1. The length L1 of the communicating pipe 60 can also be obtained by dividing the volume V3 of the space B1 of the communicating pipe 60 by the passage area S1 of the communicating pipe 60.

[0042] The lower resonator chamber 51 attenuates sound of frequency f2 obtained by substituting the volume V2 of the lower resonator chamber 51, the length L2 of the communicating pipe 61, and the passage area S2 of the communicating pipe 61 into Equation 1. The length L2 of the communicating pipe 61 can also be obtained by dividing the volume V4 of the space B2 of the communicating pipe 61 by the passage area S2 of the communicating pipe 61.

[0043] The various dimensions of the frame 31 (the dimensions of the resonator chambers 50, 51 and the communicating pipes 60, 61) are set so that the frequency f1 and the frequency f2 are, for example, 10,000 Hz or more, preferably 1,000 Hz or more. For example, the various dimensions of the frame 31 are set so that the frequency f1 and the frequency f2 are the same value.

[0044] In the outside air introduction section 20, sound waves P passing through the multiple ventilation holes 40 as shown in FIG. 6 enter the communication pipes 60, 61 in each frame 31 and are attenuated by the resonance action of the upper resonator chamber 50 and the lower resonator chamber 51.

[0045] According to this embodiment, the sound deadening structure 1 includes a frame 31 located between the left and right ventilation openings 40, and the frame 31 includes two resonator chambers 50, 51 and two communication pipes 60, 61 that communicate from each of the left and right ventilation openings 40 to the corresponding resonator chambers 50, 51. In this case, since the frame 31 of the ventilation opening 40 is used to provide a plurality of resonator chambers 50, 51, it is possible to realize a sound deadening structure 1 with a simpler structure.

[0046] The two resonator chambers 50, 51 are arranged side by side in the ventilation direction (vertical direction Z) of the ventilation port 40. In this case, since the width of the frame 31 in the left-right direction Y does not increase, the outside air introduction section 20 does not become large, and the opening area of ​​the ventilation port 40 is ensured, and multiple resonator chambers 50, 51 can be suitably provided.

[0047] The communicating pipes 60, 61 are formed using a part of the side wall of the resonator chambers 50, 51. Therefore, there is no need to provide a separate side wall for forming the communicating pipes 60, 61, which further simplifies the sound deadening structure 1 and allows the sound deadening structure 1 to be made smaller.

[0048] The communicating pipes 60, 61 are formed between the adjacent resonator chambers 50, 51. This allows the frame 31 to be made compact, and therefore the sound deadening structure 1 can be made smaller in size.

[0049] The resonator chambers 50, 51 and the communication pipes 60, 61 are formed so as to target a sound of a single frequency for sound attenuation, thereby making it possible to effectively attenuate a sound of a specific frequency f generated from a specific sound source.

[0050] The frame 31 has an elongated shape that is long in a direction perpendicular to the ventilation direction of the ventilation opening 40 (longitudinal direction X), and the two resonator chambers 50, 51 and the multiple communication pipes 60, 61 are extended along the longitudinal direction X of the frame 31. This makes it possible to muffle sound passing through the ventilation opening 40 over a wide range.

[0051] A plurality of ventilation openings 40 are arranged in one direction (long side direction Y of the frame 30), and the frames 31 are provided between adjacent left and right ventilation openings 40, respectively, so that sound passing through the outside air introduction part 20 can be effectively muffled over a wide range.

[0052] The sound deadening structure 1 is applied to a cowl louver 10 of a vehicle. In general, noise emitted from a power train such as an EV motor or engine in a vehicle passes through an outside air intake section 20, which is a gap in the cowl louver 10, and is released to the outside of the vehicle. As a result, the outside sound pressure incident on the windshield glass, etc. increases, which can be a factor in impairing comfort in the vehicle cabin. According to this embodiment, by providing the sound deadening structure 1 to the cowl louver 10 of the vehicle, it is possible to reduce noise and improve comfort in the vehicle cabin without providing a new sound deadening device to the cowl louver 10.

[0053] In addition, vehicles equipped with devices having a voice recognition function require a particularly quiet interior. Vehicles powered by a motor have a high level of quietness in terms of low-frequency sounds, but in return, they require quietness in terms of wind noise and road noise, which are mainly high-frequency sounds. Furthermore, vehicles with an automatic driving function require quietness in terms of high-frequency sounds so that passengers can have clear conversations with each other. There are great benefits to providing such vehicles with the soundproofing structure 1 of the present invention.

[0054] In this embodiment, the resonator chambers 50, 51 of the frame 31 may be provided with a sound absorbing material 110 as shown in Fig. 7. In this case, it is estimated that the frame 31-2 having the sound absorbing material 110 will have an improved sound deadening effect at frequencies f1 and f2 compared to the frame 31-1 having no sound absorbing material as described in the above embodiment as shown in Fig. 8. The sound absorbing material 110 may be provided in one of the resonator chambers of the frame 31.

[0055] In this embodiment, the two resonator chambers 50, 51 and the two communicating tubes 60, 61 of the frame 31 may be formed so that sounds of a plurality of frequencies are to be silenced. In such a case, for example, various dimensions of the frame 31 are set so that the frequency f1 and the frequency f2 are different from each other. This can be realized by changing the volumes of the upper resonator chamber 50 and the lower resonator chamber 51, and the passage areas and lengths of the communicating tubes 60 and 61. FIG. 9 shows an example of a frame 31 in which the volumes of the upper resonator chamber 50 and the lower resonator chamber 51 are changed. In this example, the volume V2 of the lower resonator chamber 51 is larger than the volume V1 of the upper resonator chamber 50. FIG. 10 shows an example of a frame 31 in which the passage areas of the communicating tubes 60 and 61 are changed. In this example, the passage area S1 of the communicating tube 60 is larger than the passage area S2 of the communicating tube 61. As shown in FIG. 8, the frame 31-3 in this example can mute sounds of two different frequencies, f1 and f2.

[0056] Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, the present invention is not limited to such an example. It is clear that a person skilled in the art can come up with various modified or altered examples within the scope of the ideas described in the claims, and it is understood that such examples also naturally belong to the technical scope of the present invention.

[0057] For example, the shapes and structures of the resonator chambers 50, 51 and the communication pipes 60, 61 of the frame 31 described in the above embodiment are not limited to those of the above embodiment. In addition, the number of resonator chambers and communication pipes of the frame 31 is two in the above embodiment, but it may be three or more. The number of resonator chambers and communication pipes may be the same or different. In addition, the sound deadening structure 1 may be provided in a part of the vehicle other than the cowl louver 10. For example, the sound deadening structure 1 may be provided in a ventilation part having a vent for a cooling fan of the vehicle battery, a ventilation part having a vent for adjusting the pressure inside and outside the vehicle, etc.

[0058] The sound deadening structure according to the present invention is not limited to applications to vehicles such as automobiles, but may also be applied to things other than vehicles. [Industrial Applicability]

[0059] The present invention is useful in providing a sound-absorbing structure having a simpler structure. [Explanation of symbols]

[0060] 1 Sound deadening structure 10. Kaurluba 20 Outside air intake section 31 Frame 40 Vent 50 Upper resonator chamber 51 Lower resonator chamber 60, 61 Communication pipe

Claims

1. A sound-absorbing structure, It has a frame located between the left and right air vents, The frame is A plurality of resonator chambers; a plurality of communication pipes that communicate from each of the left and right ventilation holes to the resonator chambers corresponding to the left and right ventilation holes, respectively, and are formed between adjacent resonator chambers.

2. The sound deadening structure according to claim 1 , wherein the plurality of resonator chambers are arranged side by side in a direction in which the air passes through the vent hole.

3. 3. The sound deadening structure according to claim 1, wherein the communication pipe is formed using a part of a side wall of the resonator chamber.

4. The sound deadening structure according to any one of claims 1 to 3, wherein the plurality of resonator chambers and the plurality of communicating pipes are formed so as to target a sound of a single frequency for sound deadening.

5. The sound deadening structure according to any one of claims 1 to 3, wherein the plurality of resonator chambers and the plurality of communicating pipes are formed so as to be targets of sound deadening for a plurality of frequencies.

6. The sound-absorbing structure according to any one of claims 1 to 5, wherein at least one of the plurality of resonator chambers is provided with a sound-absorbing material.

7. The frame has an elongated shape that is long in a direction perpendicular to the ventilation direction of the ventilation hole, 7. The sound deadening structure according to claim 1, wherein the plurality of resonator chambers and the plurality of communication pipes extend along a longitudinal direction of the frame.

8. The ventilation holes are arranged in a row in one direction, The sound deadening structure according to any one of claims 1 to 7, wherein the frames are provided between adjacent left and right air vents, respectively.

9. A vehicle comprising the sound deadening structure according to any one of claims 1 to 8.

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