Vehicle rear structure

Abstract

To materialize a vehicle rear structure that inhibits noise from outside a compartment from entering the compartment without impairing air permeability or drainage capability.SOLUTION: A vehicle rear structure includes a partition wall 16 that is provided in a space S surrounded by a rear bumper 12 of a vehicle and a fender panel 14 disposed inside the rear bumper 12 and partitions the space S into an upper part and lower part. The partition wall 16 is provided with a communication hole 20 through which the upper part and lower part of the partitioned space S communicate with each other.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a vehicle rear structure.

Background Art

[0002] In a vehicle, noise from outside the vehicle compartment easily enters the vehicle compartment through a vent duct or a space along a wheel arch. In particular, in the case of a vehicle where the passenger compartment and the luggage compartment are adjacent, noise is more likely to reach the passengers, and the riding comfort may be impaired. Therefore, in order to realize a comfortable in-vehicle environment, a vehicle rear structure that effectively prevents the intrusion of noise has been conventionally proposed.

[0003] Patent Document 1 discloses a rear structure of a vehicle configured to perform air ventilation by partitioning a space formed in a vehicle body side wall portion vertically by a first partition portion and a second partition portion. In this rear structure of the vehicle, the first partition portion and the second partition portion can effectively prevent the noise outside the vehicle compartment that has entered the vehicle body side wall portion from the opening from being transmitted to the upper space portion, and since it is not necessary to install a sound-absorbing material or the like, a simple configuration can also be realized.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in order to prevent noise from entering the vehicle interior from outside the vehicle compartment, for example, members such as a partition wall that divides the space surrounded by the rear bumper and the fender panel disposed inside thereof into upper and lower spaces may be installed. In such a configuration, it is necessary to prevent noise transmission in both the upper and lower spaces, and it is also necessary to consider the drainage performance when water enters the upper space. On the other hand, with the measures to address noise and drainage problems, other issues such as an increase in the number of parts and deterioration of air permeability may occur.

[0006] Therefore, in this specification, a vehicle rear structure is realized that suppresses the intrusion of noise from outside the vehicle compartment into the vehicle interior without impairing air permeability and drainage performance.

Means for Solving the Problems

[0007] The vehicle rear structure disclosed in this specification is provided in a space surrounded by a rear bumper of a vehicle and a fender panel disposed inside the rear bumper, and includes a partition wall that divides the space into an upper part and a lower part. The partition wall is provided with communication holes that communicate the space partitioned into the upper part and the lower part.

[0008] According to the above configuration, a resonator structure in which the upper space functions as an expansion chamber is realized by the partition wall and the communication holes, and noise in both the upper and lower spaces can be reduced.

[0009] In addition, each surface connecting both ends of the partition wall of the vehicle rear structure and the portion provided with the communication holes is formed in a convex shape upward.

[0010] According to the above configuration, generation of air vortices below both ends of the partition wall can be suppressed, and air resistance can be improved.

[0011] The vehicle rear structure further includes a vent duct having a vent that communicates the vehicle interior and the vehicle exterior, and the partition wall is provided above the vent duct.

[0012] According to the above configuration, it is possible to suppress the intrusion of noise from outside the vehicle compartment into the vehicle compartment without impairing the air permeability through the vent duct.

[0013] The vehicle rear structure disclosed in this specification is provided in a space surrounded by a rear bumper of the vehicle and a fender panel disposed inside the rear bumper, and includes a partition wall that partitions the space into an upper part and a lower part. The partition wall has a side branch pipe that protrudes upward from the partition wall, and is characterized by this.

[0014] According to the above configuration, by taking in the sound of the lower space into the side branch pipe, the noise in the lower space can be reduced.

[0015] Further, a plurality of side branch pipes of the vehicle rear structure are provided, and are characterized by this.

[0016] According to the above configuration, the sound absorption effect can be enhanced more by a plurality of side branch pipes.

Effect of the Invention

[0017] According to the vehicle rear structure disclosed in this specification, it is possible to suppress the intrusion of noise from outside the vehicle compartment into the vehicle compartment without impairing the air permeability and drainage.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Best Mode for Carrying Out the Invention

[0019] Hereinafter, the vehicle rear structure will be described with reference to the drawings. In each figure, "Fr", "Up", and "Rh" indicate the front, upper, and right sides of the vehicle, respectively.

[0020] FIG. 1 is a perspective view schematically showing a vehicle to which the vehicle rear structure according to the embodiment is applied. More specifically, FIG. 1 is a perspective view of the vehicle to which the vehicle rear structure 10 is applied, seen from the rear. In FIG. 1, the right side portion of the rear bumper 12 is shown surrounded by a two-dot chain line. Also, in FIG. 1, a view in which the rear bumper 12 surrounded by this two-dot chain line is removed, that is, a view showing the inside of the rear bumper 12, is shown as an enlarged view C surrounded by a two-dot chain line.

[0021] As shown in the enlarged view C of FIG. 1, the vehicle rear structure 10 includes a fender panel 14 disposed inside the rear bumper 12. The fender panel 14 is a known fender panel that is one of the constituent panels of the vehicle body. As shown in the enlarged view C, there is a space S surrounded by the rear bumper 12 and the fender panel 14 in the vehicle rear structure 10. This space S is, for example, a space of about 3 to 5 cm in the vehicle width direction. In the enlarged view C, the space S is shown as a lightly shaded portion.

[0022] As shown in the enlarged view C of FIG. 1, the vehicle rear structure 10 further includes a partition wall 16 that partitions the space S into an upper part and a lower part, and a vent duct 18 assembled to the fender panel 14. In the enlarged view C, the partition wall 16 is shown as a hatched portion for distinction from other members. The partition wall 16 is fixed, for example, to a part of the rear bumper 12 on the outer side in the vehicle width direction and to a part of the fender panel 14 on the inner side in the vehicle width direction by an adhesive such as a double-sided tape (not shown in FIG. 1) and a sealing material, respectively. The vent duct 18 is one of the ventilation devices having a vent that communicates the interior of the vehicle with the exterior of the vehicle. As shown in the enlarged view C, the partition wall 16 is provided above the vent duct 18 in the vertical direction of the vehicle.

[0023] Next, with reference to FIG. 2, the configuration of the vehicle rear structure 10 will be further described. FIG. 2 is a cross-sectional view taken along the line A-A of the vehicle rear structure of FIG. 1. As shown in FIG. 2, in the vehicle rear structure 10, a communication hole 20 that communicates the space S with the partition wall 16 is provided. In FIG. 2, this communication hole 20 is shown as a lightly shaded portion. Also, in FIG. 2, the partition wall 16 is surrounded by a two-dot chain line and shown as an enlarged view D. Further, in order to show the shape of the communication hole 20 and its surroundings, the cross-section of this portion is surrounded by a one-dot chain line as a cross-sectional view taken along the line B-B and shown as FIG. E. As shown in the cross-sectional view taken along the line B-B of FIG. E, the respective surfaces connecting both ends of the partition wall 16 and the communication hole 20 are formed in a convex shape upward. Details of the partition wall 16 formed in this convex shape will be described later.

[0024] Next, with reference to FIGS. 3 to 5, the configuration of the vehicle rear structure 10 and its operation and effects will be further described. FIGS. 3 to 5 are diagrams for comparing an example of the vehicle rear structure with the conventional structure. Note that FIGS. 3 to 5 are diagrams showing the same portions of the vehicle rear structure 10 shown in FIG. 2 from the same direction. FIG. 3 shows three structures arranged side by side: a structure without a partition wall, a structure with a partition wall, and a structure in which a communication hole is further provided in the partition wall, which is a feature of the vehicle rear structure according to the embodiment. In the three structures shown in FIG. 3, the arrows indicated by the broken lines represent an image of sound invading from outside the vehicle compartment. Also, Pa1, Pa2, and Pa3 represent the loudness of the sound in the space above the space S (reference numerals omitted in FIGS. 3 to 6) surrounded by the rear bumper 12 and the fender panel 14, Pb1, Pb2, and Pb3 represent the loudness of the sound in the space below the space S, and Pc1, Pc2, and Pc3 represent the loudness of the sound in the vehicle compartment, respectively.

[0025] Here, when comparing the loudness of the sound in the three structures, it can be estimated that the sound Pa1 in the structure without the partition wall is the largest above the space S. This is because, compared to the other two structures without the partition wall, the sound is more likely to invade upward. And it can be estimated that the sound Pa3 in the structure with the communication hole 20 provided in the partition wall 16 is the second largest. This is because, due to the provision of the communication hole 20, a part of the sound from below invades upward. That is, it can be estimated that the magnitude relationship of the loudness of the sound in the space above the space S is Pa1 > Pa3 > Pa2.

[0026] On the other hand, it can be estimated that the sound Pb2 is the largest within the structure where the partition wall 16 without communication holes is located below the space S. This is presumably because the sound is prevented from transmitting upward by the partition wall 16, and thus the sound pressure increases due to reflection from the partition wall 16 compared to the other two structures. Next, when comparing the structure without the partition wall 16 and the structure with the communication hole 20 provided in the partition wall 16, it can be estimated that the sound in the lower space of the space S is greater in the structure without the partition wall 16. In the structure with the communication hole 20 provided in the partition wall 16, a resonator structure with a function as an expansion chamber is realized in the space above the partition wall 16 and the communication hole 20. Therefore, since the sound absorption effect by the resonator structure is exerted, it can be estimated that the sound Pb3 is smaller than the sound Pb1 in the space without the sound absorption structure. That is, it can be estimated that the magnitudes of the sounds in the lower space of the space S are in the order of Pb2 > Pb1 > Pb3.

[0027] Then, when comparing the magnitudes of the sounds in the vehicle interior based on the above Pa1 > Pa3 > Pa2 and Pb2 > Pb1 > Pb3, it can be estimated that they are in the order of Pc1 > Pc2 > Pc3. That is, the structure disclosed in this specification with the communication hole 20 provided in the partition wall 16 can reduce the noise in both the upper and lower spaces, and thus can more effectively suppress the noise entering the vehicle interior compared to the other two structures. As described above, this is because the vehicle rear structure 10 forms a resonator structure by the space S, the partition wall 16, and the communication hole 20, and the space above the space S serves as an expansion chamber, thereby realizing a sound absorption structure. In this structure, for example, the sound absorption frequency can be adjusted by changing the length of the communication pipe portion of the communication hole 20 in the vehicle vertical direction or by changing the passage area of the communication pipe. Therefore, for example, a structure with a higher sound absorption effect can be achieved for each vehicle type.

[0028] Figure 4 shows two structures side by side: a structure with a partition wall and a structure with through holes further provided in the partition wall. The lightly shaded portions shown in Figure 4 represent water droplets. As shown in Figure 4, when the space is partitioned into upper and lower parts by the partition wall 16, for example, water that has entered from the end of the bumper or the like may accumulate on the upper surface of the partition wall 16. On the other hand, in the structure in which the through hole 20 is provided in the partition wall 16, drainage is promoted from the through hole 20. Therefore, in the structure in which the through hole 20 is provided in the partition wall 16, there is a secondary effect that the drainage property is also improved.

[0029] Figure 5 shows two structures side by side: a structure with a partition wall and a structure with through holes further provided in the partition wall. In the two structures shown in Figure 5, the arrows indicated by the broken lines represent an image of a part of the air flow discharged from the passenger compartment through the vent duct 18. As shown in Figure 5, in the structure provided with the partition wall 16, a small vortex W may be generated particularly around the end of the lower part of the partition wall 16. On the other hand, in the vehicle rear structure 10 in which the through hole 20 is provided in the partition wall 16 and the respective surfaces connecting both ends of the partition wall 16 and the through hole 20 portion are convex upward, it can be estimated that the air separation around the end of the partition wall 16 is small. That is, in such a configuration, since the air flows along the shape because the periphery of the end of the partition wall 16 is formed in an arc shape, it is difficult for vortices to be generated. Therefore, in the structure in which the through hole 20 is provided in the partition wall 16, there is a secondary effect that the air resistance is also improved.

[0030] In the conventional structure with only the partition wall 16 as shown in FIG. 5, the cross-section of the peripheral portion of the end of the partition wall 16 (that is, the portion where the vortex W is generated and its periphery) is formed at an acute angle. In the space portion, sound is likely to concentrate from the side with a larger cross-sectional area toward the side with a smaller cross-sectional area. In the conventional structure with only the partition wall 16, the sound is more likely to concentrate at the corner portion. On the other hand, in the structure in which the communication hole 20 is provided in the partition wall 16 and the respective surfaces connecting both ends of the partition wall 16 and the communication hole 20 portion are convex upward, the concentration of sound at the corner portion is suppressed. Therefore, in the structure in which the communication hole 20 is provided in the partition wall 16, there is also an effect of preventing the concentration and amplification of sound.

[0031] Next, with reference to FIG. 6, a modified example of the vehicle rear structure will be described. FIG. 6 is a view showing another example of the vehicle rear structure. The same members as those in FIG. 2 are denoted by the same reference numerals, and the description will be omitted as appropriate. In the vehicle rear structure 10 shown in FIG. 6, the partition wall 16 has a side branch pipe 22 that protrudes upward from the partition wall 16. This side branch pipe 22 is integrally formed with the partition wall 16. By forming the side branch pipe 22, the noise from outside the vehicle compartment that has entered the lower space in the space S can be taken into the pipe. As a result, the noise entering the vehicle compartment can be suppressed. That is, by adding the internal space of the side branch pipe 22 to the space above the partition wall 16, the noise is reduced.

[0032] Also, in FIG. 6, two side branch pipes 22 with different lengths in the vehicle vertical direction are provided. By providing a plurality of side branch pipes 22 with different shapes such as length and diameter, noise reduction at multiple frequencies becomes possible. Also, by providing a plurality of side branch pipes 22 with the same length, noise reduction at a specific frequency can be performed more effectively. Further, similar to the vehicle rear structure 10 shown in FIG. 2, in the vehicle rear structure 10 in this modified example, by providing the side branch pipes 22 above the vent duct 18, ventilation of the vent duct 18 in the lower space in the space S is not obstructed. Therefore, in the vehicle rear structure according to the modified example, it is possible to achieve both noise countermeasures and ensuring ventilation.

[0033] Note that the above description is an example. In the vehicle rear structure disclosed in this specification, it is sufficient to include a partition wall that divides the space surrounded by the rear bumper and the fender panel into upper and lower parts, and the partition wall is provided with communication holes that communicate the spaces partitioned into upper and lower parts. Therefore, other configurations may be appropriately changed. For example, in this example, the communication hole 20 is circular as shown in the enlarged view D of FIG. 2, but it is not limited to this, and it may be formed in an elliptical or honeycomb shape, etc.

Explanation of Reference Numerals

[0034] 10 Vehicle rear structure, 12 Rear bumper, 14 Fender panel, 16 Partition wall, 18 Vent duct, 20 Communication hole, 22 Side branch pipe, S Space, W Vortex.

Claims

1. A vehicle rear structure provided in a space surrounded by a rear bumper of a vehicle and a fender panel disposed inside the rear bumper, the vehicle rear structure comprising a partition wall that partitions the space into an upper part and a lower part, wherein the partition wall is provided with a communication hole that allows communication between the space partitioned into the upper part and the lower part.

2. Each surface connecting both end portions of the partition wall and the portion where the communication hole is provided is formed in a convex shape upward.

3. The vehicle rear structure further includes a vent duct having a vent hole that allows communication between the inside of the vehicle compartment and the outside of the vehicle, wherein the partition wall is provided above the vent duct.

4. A vehicle rear structure provided in a space surrounded by a rear bumper of a vehicle and a fender panel disposed inside the rear bumper, the vehicle rear structure comprising a partition wall that partitions the space into an upper part and a lower part, wherein the partition wall has a side branch pipe that protrudes upward from the partition wall.

5. A plurality of the side branch pipes are provided. ​ ​ ​ ​ ​

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