Duct

Abstract

To provide a novel duct.SOLUTION: A duct which is installed in an opening of a housing has a first wall that forms a path that intersects an air flow direction of the housing, and the first wall is equipped with a resonator that attenuates sound from the housing and a reflector that reflects sound from the housing.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to ducts. [Background technology]

[0002] Patent Document 1 discloses a duct equipped with a Helmholtz resonator.

[0003] [Patent Document 1] JP 2019-120161 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a novel duct. [Means for solving the problem]

[0005] The duct of the present disclosure is a duct that is arranged at an opening of a housing, the duct having a first wall that forms a path that intersects with the air blowing direction of the housing, and a resonator that attenuates sound from the housing and a reflector that reflects sound from the housing are arranged on the first wall. Effect of the Invention

[0006] According to the present disclosure, a novel duct can be provided. [Brief description of the drawings]

[0007] [Figure 1] FIG. [Diagram 2] FIG. 4 is a perspective view showing the arrangement relationship between the housing and the duct. [Diagram 3] FIG. 3 is a cross-sectional view showing the section AA of FIG. 2. [Figure 4] FIG. 3 is a cross-sectional view showing the cross section BB of FIG. 2. [Diagram 5] Front view of the duct. [Figure 6] FIG. 6 is a cross-sectional view showing the CC section of FIG. 5 . [Figure 7] Top view of the duct. [Figure 8] FIG. 7 is an enlarged cross-sectional view of a portion D in FIG. 6. [Figure 9] FIG. [Figure 10] FIG. 13 is a cross-sectional view showing another embodiment of the duct. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each drawing, mutually orthogonal X, Y and Z axes are shown for specifying directions.

[0009] As shown in FIG. 1, the duct 1 is a tubular resin member having a first opening 1a and a second opening 1b opposite to the first opening 1a. The duct 1 has a tube portion 10 and a flange portion 15 connected to the upper end of the tube portion 10. The flange portion 15 is provided at the first opening 1a of the duct 1. In this embodiment, the tube portion 10 has a first wall 11, a second wall 12 arranged opposite to the first wall 11, a third wall 16 connected between the first wall 11 and the second wall 12, and a fourth wall 17 connected between the first wall 11 and the second wall 12 and arranged opposite to the third wall 16. A resonator 13 and a reflector 14 are arranged on the first wall 11.

[0010] 2 and 3, the duct 1 is disposed, for example, between an opening Ta of a floor member T of the vehicle and an opening 31 of a housing 3 disposed below the floor member T of the vehicle (the floor member T is omitted in FIG. 2). The tube portion 10 is inserted into the opening Ta of the floor member T and disposed in the opening 31 of the housing 3. The flange portion 15 is fixed to the floor member T. The housing 3 incorporates an electronic component E. The duct 1 and the housing 3 form a path R for passing cooling air that cools the electronic component E.

[0011] The electronic component E in this embodiment is an ECU (Electronic Control Unit) for controlling electrical equipment of the vehicle. The housing 3 further includes a noise source S. In this embodiment, the noise source S is a motor M and a cooling fan F driven by the motor M.

[0012] When the motor M is driven to rotate by a control unit (not shown), the cooling fan F rotates and draws cooling air (see the white arrow in FIG. 3) into the duct 1 and the housing 3. The cooling air is taken in from the vehicle interior and cools the electronic components E through the path R formed by the duct 1 and the housing 3. Meanwhile, the sound generated by the rotational driving of the motor M and the cooling fan F is transmitted through the path R toward the vehicle interior.

[0013] The path R has a first path R1 along the airflow direction of the housing 3 (arrow X direction in FIG. 3), a second path R2 intersecting the first path R1, and a curved space R3 connecting the first path R1 and the second path R2. The first path R1 is formed by the housing 3. The second path R2 is formed by the duct 1 (first wall 11, second wall 12, third wall 16, and fourth wall 17). The curved space R3 is formed by the duct 1 (first wall 11, third wall 16, and fourth wall 17) and the housing 3. In this embodiment, the second path R2 and the curved space R3 form a path of the path R that intersects with the airflow direction of the housing 3.

[0014] 3, the first wall 11 has a first end 11a on the first opening 1a side and a second end 11b on the second opening 1b side. The first end 11a is disposed near the opening Ta of the floor member T. The second end 11b is disposed near the bottom surface exposed to the opening 31 of the housing 3. The second end 11b may be in contact with the bottom surface of the housing 3, or may have a gap between it and the bottom surface of the housing 3.

[0015] The second wall 12 has a first end 12a on the first opening 1a side and a second end 12b on the second opening 1b side. The first end 12a is disposed near the opening Ta of the floor member T. The second end 12b is disposed near the upper surface of the housing 3 in the vicinity of the opening 31. The second end 12b may be in contact with the upper surface of the housing 3, or there may be a gap between the second end 12b and the upper surface of the housing 3.

[0016] In this embodiment, the first end 11a of the first wall 11 is located at the same position as the second end 12b of the second wall 12 in the vertical direction (the direction of the arrow Z in FIG. 3). On the other hand, the second end 11b of the first wall 11 is located below the second end 12b of the second wall 12 (the direction of the arrow Z in FIG. 3). That is, the first wall 11 extends below the second wall 12. The first wall 11 has an area facing the curved space R3. In this embodiment, the resonator 13 and the reflector 14 are disposed in the area of ​​the first wall 11 facing the curved space R3.

[0017] 3, the resonator 13 is provided on the first wall 11 and faces the noise source S. Sound generated by the noise source S is transmitted to the resonator 13 through a first path R1. The resonator 13 is a Helmholtz resonator that attenuates sound from the housing 3. The resonator 13 of this embodiment attenuates sound having a first frequency among sounds generated by the noise source S.

[0018] As shown in FIG. 6, the resonator 13 has a chamber 13a and an opening 13b. The chamber 13a is a resonance space of the Helmholtz resonator. The opening 13b is an opening of the Helmholtz resonator. Furthermore, the opening 13b is a passage connecting the resonance space of the Helmholtz resonator and the bending space R3. In this embodiment, the thickness of the opening 13b in the length direction (the direction of the arrow X in FIG. 3) is the length of the passage of the Helmholtz resonator. The volume of the chamber 13a, the area of ​​the opening 13b, and the length of the opening 13b are adjusted based on the frequency (first frequency) of the sound to be attenuated.

[0019] Similarly, the reflector 14 is provided on the first wall 11 and faces the noise source S. The sound generated by the noise source S is transmitted to the reflector 14 through the first path R1. The reflector 14 reflects a sound generated by the noise source S that has a second frequency different from the first frequency. The second frequency is a frequency higher than the first frequency. In this embodiment, the first frequency is approximately 1000 Hz, and the second frequency is approximately 6000 Hz. The first frequency and the second frequency are not limited to this, and can be changed in various ways depending on the sound generated by the noise source S in the housing 3.

[0020] When the reflector 14 receives a sound from the housing 3, it reflects the sound and emits a sound of the opposite phase. The sound of the opposite phase travels through the first path R1 (see FIG. 4) in the opposite direction to the sound from the housing 3, and cancels out the sound from the housing 3. In this way, the reflector 14 can reflect and attenuate the sound from the housing 3.

[0021] 6, the reflector 14 is disposed in the longitudinal direction of the duct 1 (the X direction in FIG. 6) at a distance d from the inner wall of the first wall 11 where the opening 13b of the resonator 13 is provided. By adjusting the distance d, the distance between the reflector 14 and the noise source S is adjusted to a distance suitable for attenuating the second frequency.

[0022] The resonator 13 and the reflector 14 can attenuate different frequencies of the sounds from the housing 3. Therefore, the duct 1 can attenuate sounds of multiple frequencies simultaneously by using the resonator 13 and the reflector 14.

[0023] Furthermore, the resonator 13 and the reflector 14 are provided on the first wall 11 that forms the curved space R3, and more specifically, are provided in a region of the first wall 11 that faces the curved space R3. That is, the resonator 13 and the reflector 14 are disposed facing the first path R1, and therefore the noise source S. As a result, the sound emitted from the noise source S is directly transmitted to the resonator 13 and the reflector 14. As a result, the duct 1 can efficiently attenuate the sound transmitted from the noise source S.

[0024] Furthermore, the resonator 13 and the reflector 14 are arranged side by side in the width direction (arrow Y direction in FIG. 5) of the duct 1. This reduces the vertical length of the duct 1 compared to an arrangement in which the resonator 13 and the reflector 14 are arranged side by side in the vertical direction of the duct 1 (Z direction in FIG. 5). As a result, the duct 1 and the housing 3 can be accommodated in a limited space under the floor.

[0025] As shown in Fig. 5, in this embodiment, the resonator 13 is disposed at the center of the first wall 11 in the width direction of the duct 1 (the direction of the arrow Y in Fig. 5). In this embodiment, there are a plurality of reflectors 14 (two in this embodiment). The resonator 13 is disposed between the two reflectors 14.

[0026] The resonator 13 has a relatively large number of design parameters (volume of the chamber 13a, area of ​​the opening 13b, and length of the opening 13b), and therefore requires a relatively complicated design to adjust it so as to attenuate the sound of the first frequency. During design, the resonator 13 is first placed on the first wall 11, and then the two reflectors 14 are placed in the surplus space on both sides of the resonator 13, making it relatively easy to design the duct 1.

[0027] Furthermore, since the resonator 13 is disposed between the two reflectors 14, the resonator 13 and the reflectors 14 can be disposed evenly in the width direction of the duct 1, and sounds of the frequencies attenuated by the resonator 13 and the reflectors 14, respectively, can be efficiently attenuated.

[0028] As shown in FIG. 7, the resonator 13 and the reflector 14 may be disposed on the inside of the outer circumferential edge 15a of the flange portion 15 when viewed from the first opening 1a of the duct 1.

[0029] This allows the entire duct 1 to be formed compactly. Therefore, when the duct 1 is placed on the floor member T (see FIG. 3), the resonator 13 and the reflector 14 can easily pass through the opening Ta (see FIG. 3). As a result, the duct 1 can be easily attached to the housing 3.

[0030] 9, the first wall 11 of the duct 1 is composed of a first member 18 and a second member 19. By forming the first wall 11 from the first member 18 and the second member 19, it is possible to realize a complex shape of the first wall 11 having the resonator 13 and the reflector 14 while adjusting the sound frequencies attenuated by the resonator 13 and the reflector 14, respectively.

[0031] The first member 18 has a first portion 18a and a second portion 18b. The first portion 18a forms the chamber 13a of the resonator 13 together with the second member 19 (see FIG. 6). The second portion 18b forms the reflector 14.

[0032] The second member 19 forms the tube portion 10 together with the second wall 12, the third wall 16, and the fourth wall 17. The second member 19 has a first communicating portion 19a and a second communicating portion 19b. The first communicating portion 19a is an opening 13b that communicates the chamber 13a of the resonator 13 with the bending space R3. The second communicating portion 19b communicates the reflection space R4 with the bending space R3 (see FIG. 4). Here, the reflection space R4 means a space provided between the reflection plate 14 and the bending space R3 by disposing the second portion 18b that forms the reflection plate 14 at a distance d (see FIG. 4 or FIG. 6) from the inner wall of the second member 19.

[0033] The second member 19 is attached to the first member 18 to form the first wall 11. The first member 18 and the second member 19 are joined at a first joint portion 20 and a second joint portion 21. The first member 18 and the second member 19 are joined at the first joint portion 20 with a joint structure that has a higher sealing strength than the second joint portion 21.

[0034] At the first joint 20, the first portion 18a of the first member 18 is joined to the second member 19. As shown in FIG. 8, the first joint 20 of this embodiment has a spigot structure 20a between the outer periphery of the first portion 18a of the first member 18 and the outer wall around the first communicating portion 19a of the second member 19. The spigot structure 20a is formed continuously around the entire circumference surrounding the chamber 13a. This can improve the sealing between the first member 18 and the second member 19, and can seal the chamber 13a of the resonator 13 except for the opening 13b.

[0035] At the second joint 21, the second portion 18b of the first member 18 is joined to the second member 19 with a joint structure different from that of the first joint 20. In this embodiment, a spigot structure is not provided at the second joint 21, and the first member 18 and the second member 19 are joined by an adhesive. However, the present invention is not limited to this, and the first member 18 and the second member 19 may be joined at the second joint 21 by thermal caulking.

[0036] As described above, according to the present disclosure, a novel duct can be provided.

[0037] <Other embodiments> Although the embodiment of the present disclosure has been described above, the present disclosure is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention. In particular, the multiple modifications described in this specification can be arbitrarily combined as necessary.

[0038] Although the duct 1 of the present embodiment is attached to a housing 3 that incorporates an ECU for a vehicle, the present disclosure is not limited to this. In other words, the duct 1 is not limited to one that is disposed inside the passenger compartment of a vehicle, and may be any tubular member that forms a ventilation path.

[0039] The duct 1 of this embodiment has a straight tube-shaped tubular portion 10, but the present disclosure is not limited thereto. For example, as shown in FIG. 10, the tubular portion 10 of the duct 1 may be L-shaped having a first tubular portion 10a and a second tubular portion 10b extending in a direction intersecting the first tubular portion 10a. Specifically, the first tubular portion 10a extends in the height direction (arrow Z direction in FIG. 10). A flange portion 15 is formed at the end portion on the first opening 1a side. The second tubular portion 10b extends in the length direction (arrow X direction in FIG. 10) from the end portion of the first tubular portion 10a opposite to the side where the flange portion 15 is provided. The second opening 1b of the duct 1 is disposed opposite to the opening 31 of the housing 3.

[0040] The resonator 13 in this embodiment is disposed inside the outer peripheral edge of the flange portion 15 as viewed from the first opening 1a of the duct, but the present disclosure is not limited thereto. For example, as shown in FIG. 10, the resonator 13 may be disposed outside the outer peripheral edge of the flange portion 15 as viewed from the first opening 1a of the duct 1. Similarly, the reflector 14 may be disposed outside the outer peripheral edge of the flange portion 15 as viewed from the first opening 1a of the duct 1. Also, as shown in FIG. 10, the second opening 1b of the duct 1 may be disposed outside the outer peripheral edge of the flange portion 15 as viewed from the first opening 1a of the duct 1.

[0041] Furthermore, the duct 1 of this embodiment has been described using an example having one resonator 13 and two reflectors 14, but the present disclosure is not limited to this. That is, the number of resonators 13 and reflectors 14 can be changed depending on the size and shape of the duct 1 and the frequency of the sound to be attenuated. In addition, the resonators 13 and the reflectors 14 may be arranged side by side along the height direction of the duct 1 (the direction of the arrow Z in FIG. 1).

[0042] In addition, although the two reflectors 14 in this embodiment reflect and attenuate the sound of the second frequency, the present disclosure is not limited to this. That is, the multiple reflectors 14 may each reflect sounds of different frequencies. [Explanation of symbols]

[0043] 1: Duct 3: Housing 31 :Aperture 11: 1st wall 12:Second wall 13: Resonator 14:Reflector 15: Flange part 15a: Outer edge

Claims

1. A duct disposed at an opening of the housing, The duct has a first wall that forms a path that intersects with a direction of airflow through the housing, A resonator that attenuates sound from the housing and a reflector that reflects sound from the housing are disposed on the first wall. duct.

2. The reflector includes a plurality of reflectors. The resonator is disposed between a plurality of the reflectors. The duct of claim 1.

3. The first wall is a first member; and a second member to which the first member is attached to form the path; having The first member has a first portion that forms a chamber of the resonator and a second portion that forms the reflector, The second member has a first communication portion that communicates the chamber with the passage, and a second communication portion that communicates the passage with a reflection space formed by the second portion. The duct of claim 1.

4. The first portion is attached to the first member by a joint structure having a higher sealing property than the second portion. A duct as claimed in claim 3.

5. The duct further includes a flange portion provided at an opening of the duct, The resonator and the reflector are disposed on the inside of the outer circumferential edge of the flange portion when viewed from the opening of the duct. The duct of claim 1.

Images