JP3653763B2 - Silencer - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a silencer, and more particularly, to a silencer capable of ventilation.
[0002]
[Prior art]
Conventionally, in order to reduce the engine noise of the vehicle outside the vehicle, there are methods such as attaching a sound absorbing material inside the engine room or providing a shielding plate at the bottom of the vehicle. However, according to these methods, ventilation to the engine room is hindered by the sound absorbing material or the shielding plate. For this reason, there is a problem that a sound absorbing material or a shielding plate cannot be installed in an opening such as a grill or a bumper from the viewpoint of engine cooling, and sound is emitted from the opening to the outside of the vehicle.
[0003]
As a silencer capable of ventilation, for example, Japanese Patent Publication No. 5-78040 discloses a duct using a sound absorber utilizing Helmholtz resonance. In this device, a cell in which at least two or more stages of resonance chambers having different resonance frequencies are arranged in the radial direction is arranged in the circumferential direction and the axial direction to form a cylindrical body that forms an air passage inside, and this cylinder is formed in the duct. Sound absorbing ducts that allow ventilation are formed by stacking bodies in a bowl or series.
[0004]
[Problems to be solved by the invention]
However, according to the above-mentioned Japanese Patent Publication No. 5-78040, the structure of the silencer is complicated because the resonance chambers are stacked in two or more stages. In addition, there is a problem that if the sinus volume of the resonance chamber is secured, the opening area of the air passage is reduced and the air resistance of the entire silencer is increased. Furthermore, when a cylindrical body is stacked in the duct as described above, there is a problem that the pressure loss of the silencer as a whole is large due to the shape of the wall portion of the cylindrical body.
[0005]
An object of the present invention is to provide a silencer that has a simple structure and has low air resistance and allows ventilation.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, a silencer according to claim 1 of the present invention is a silencer having a plate-like portion and formed with a plurality of parallel air passages penetrating in the thickness direction. ,
A partition wall for partitioning adjacent air passages, the partition wall including a Helmholtz resonator having a cavity communicating with the air passage, and a cross-sectional shape of the air passage inlet portion or the air passage outlet portion of the partition wall is a curved surface Ri shape der, the Helmholtz resonator, the cavity, and comprises an outer wall having a communicating hole communicating with the air passage and the cavity, and the communication hole, the air passage during installation of the silencer It is provided in the said outer wall of the part located upwards, It is characterized by the above-mentioned .
[0007]
Muffler according to claim 2 of the present invention is a muffler according to claim 1, before Symbol septum, characterized by comprising the Helmholtz resonator at a position surrounding the air passages.
[0008]
The silencer according to claim 3 of the present invention is the silencer according to claim 1 or 2 , wherein the resonance frequency of the Helmholtz resonator is different for each unit of the air passage communicating with the cavity. .
A silencer according to a fourth aspect of the present invention is the silencer according to any one of the first to third aspects, wherein a cross-sectional shape of the air passage with respect to a direction perpendicular to a direction in which the air passage extends is a polygonal shape. It is characterized by being.
[0009]
A silencer according to claim 5 of the present invention is the silencer according to any one of claims 1 to 4 , wherein the silencer has a coupling structure capable of combining a plurality of the silencers on an outer periphery. To do.
[0010]
A silencer according to a sixth aspect of the present invention is the silencer according to any one of the first to fifth aspects, and is made of a transparent resin material .
[0011]
A silencer according to a seventh aspect of the present invention is the silencer according to any one of the first to sixth aspects, wherein the silencer is provided at a front portion of a radiator in an opening of an engine room of a vehicle. Features.
A silencer according to an eighth aspect of the present invention is the silencer according to any one of the first to sixth aspects, wherein the silencer is attached to an air outlet of an air conditioner.
[0012]
[Operation and effect of the invention]
According to the silencer of the first aspect of the present invention, since the Helmholtz resonator is provided in the partition wall that partitions the air passages, a silencer capable of passing air can be obtained. Moreover, since the cross-sectional shapes of the air passage inlet and the air passage outlet of the partition wall are curved, the air resistance of the air passing through the silencer is small.
[0013]
Furthermore , according to the silencer of the first aspect of the present invention, since the outer wall constituting a part of the partition wall forms a cavity and a communication hole, the Helmholtz resonator is configured in a small space inside the partition wall. The sound passing through the air passage can be efficiently attenuated by the resonator.
Furthermore, according to the silencer according to claim 1 of the present invention, since the communication hole is provided in the outer wall of the portion located above the air passage when the silencer is attached, water, dust, etc. are present in the cavity in the partition wall. There is an effect to prevent entering.
According to the silencer of the second aspect of the present invention, since the Helmholtz resonator is formed at the position surrounding the air passage, the Helmholtz resonator is densely arranged around the air passage. Thereby, since the Helmholtz resonator can be efficiently arranged in the volume of the portion other than the air passage of the silencer, the air resistance can be reduced by increasing the opening area of the air passage.
[0014]
According to the silencer according to claim 3 of the present invention, since a plurality of air passages having different silencing characteristics are formed in one silencer, the silencer as a whole can obtain a high attenuation effect on a wideband sound. it can.
According to the silencer of claim 4 of the present invention, since the cross-sectional shape of the air passage is a polygonal shape, the air passage can be efficiently arranged in the silencer, and the air flow rate direction of the silencer can be increased. Can be high.
[0015]
According to the silencer according to claim 5 of the present invention, a silencer having a desired area can be easily obtained by combining a plurality of silencers by the coupling structure provided on the outer periphery of the silencer.
[0016]
According to the silencer of the sixth aspect of the present invention, since the silencer is formed of a transparent resin material, the daylighting ability and the light transmission through the silencer are good .
[0017]
According to muffler according to claim 7 of the present invention, by providing the front portion of the radiator silencer having air permeability at the opening of the engine compartment of a vehicle, the engine while securing the radiator, the cooling of the engine room Noise leaking from the room opening to the outside of the vehicle can be reduced. In addition, the silencer according to the present invention is designed such that the cross-sectional area and length of the neck of the Helmholtz resonator, the volume of the cave, and the cross-sectional area of the air passage are designed to desired values. It is possible to design the appearance of the neck and the sinus. For this reason, a silencer can be installed without deteriorating the appearance of the vehicle. Furthermore, since the silencer according to the present invention can have a panel-like thin structure, it is advantageous when mounted at the above position of the vehicle.
[0018]
According to the silencer of the eighth aspect of the present invention, the air blowing sound of the air conditioner can be reduced by attaching the breathable silencer to the air outlet of the air conditioner.
[0019]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
A first embodiment of the present invention is shown in FIGS.
A schematic structure of the Helmholtz resonator is shown in FIG.
[0020]
The Helmholtz resonator 100 includes a wall body 105 having an air passage 103, a sinus portion 102 in which a large volume cavity 106 is formed, and a neck portion 101 having a communication hole 107 for communicating the air passage 103 and the cavity 106. Is done. The sound passing through the air passage 103 causes vibration of air in the communication hole 107 and expansion and contraction of air in the cavity 106. The resonance phenomenon caused by this attenuates sound at the air passage 103 side entrance of the communication hole 106 of the neck 101.
[0021]
The resonance frequency fr is determined by the cross-sectional area and length of the communication hole 107 and the volume of the cavity 106. As shown in FIG. 5, the sound attenuation is greatest near the resonance frequency fr. The sound attenuation is determined by the cross-sectional area and length of the communication hole 107, the volume of the cavity 106, and the cross-sectional area of the air passage 103. The attenuation amount tends to decrease as the cross-sectional area of the air passage 103 increases. By designing these parameters, it is possible to freely change the silencing characteristics of the silencer including the Helmholtz resonator 100.
[0022]
1, 2 and 3 show an embodiment of a silencer using a Helmholtz resonator. As shown in FIGS. 1, 2, and 3, the silencer 10 according to the first embodiment of the present invention is a plate-like structure when viewed from the outside, and a plurality of air passages 14 extending in parallel are partitioned by partition walls 18. ing. Inside the partition wall 18, a plurality of Helmholtz resonators 15 are formed so as to surround four sides of each air passage 14.
[0023]
A cavity 17 divided by a partition plate 19 is formed inside the partition wall 18, and one or more communication holes 16 communicating with the air passage 14 are formed in the partition wall 18. The partition wall 18 around the communication hole 16 corresponds to the neck portion of the Helmholtz resonator 15, and the partition wall 18 and the partition plate 19 around the cavity 17 correspond to the sinus portion of the Helmholtz resonator 15. By adjusting the cross-sectional area and length of the communication hole 16, the volume of the cavity 17, and the cross-sectional area of the air passage 14, the silencer 10 having a desired silencing characteristic can be obtained. Further, as shown in FIG. 1, the inlet side end 18a and the outlet side end 18b of the partition wall 18 are formed in a curved shape in order to reduce the air resistance.
[0024]
When air with sound flows into the air passage 14 from the left direction to the right direction of the silencer 10 shown in FIG. 1, the air passage side of the communication hole 16 of the Helmholtz resonator 15 and the air in the cavity 17 resonate and communicate with each other. Sound is attenuated at the entrance of the hole 16.
According to the above structure, the cavity 17 of the Helmholtz resonator 15 is provided in the partition wall 18 that partitions adjacent air passages so that a large number of air passages 14 extend in parallel in the thickness direction of the plate-like structure. Using the volume of the partition wall 18, the volume of the cavity 17 can be efficiently secured at a position surrounding the air passage 14 inside the partition wall 18. For this reason, since it becomes possible to enlarge the passage cross-sectional area of the air passage 14, the air resistance of the silencer 10 can be reduced. Furthermore, since the inlet side end 18a and the outlet side end 18b of the partition wall 18 are formed in a curved surface shape, there is an effect that the air resistance in the air passage 14 is reduced and the pressure loss can be reduced. Moreover, since this plate-like structure is a simple structure, the silencer 10 can be easily manufactured.
[0025]
(Second embodiment)
A second embodiment of the present invention is shown in FIGS. The second embodiment is an example in which Helmholtz resonators having different resonance frequencies are provided around each air passage of the silencer of the first embodiment.
As shown in FIGS. 6 and 7, the silencer 20 according to the second embodiment of the present invention is a plate-like structure when viewed from the outside, and has a plurality of air passages 24 a, 24 b, 24 c extending in parallel by the partition walls 28. 24d are partitioned. Inside the partition wall 28, a plurality of Helmholtz resonators 25a, 25b, 25c, 25d (24b, 24d are not shown) are formed to surround the air passages 24a, 24b, 24c, 24d. . A, B, C, and D in FIG. 6 are represented by Helmholtz resonators 25a, 25b, 25c, and 25d in which the air passages 24a, 24b, 24c, and 24d have the resonance frequencies A, B, C, and D shown in FIG. Indicates that each is enclosed.
[0026]
In the second embodiment of the present invention, as shown in FIG. 7, a Helmholtz resonator 25a including a communication hole 26a and a cavity 27a is formed inside a partition wall 28 around the air passage 24a, A Helmholtz resonator 25c including a communication hole 26c and a cavity 27c is formed inside the partition wall 28. The cross-sectional areas and lengths of the communication holes 26a and 26c are different from each other, and the volumes of the sinuses 27a and 27c are different from each other, so that the Helmholtz resonators 25a and 25c have different resonance frequencies. Yes.
[0027]
According to said structure, as shown in FIG. 8, the silencer with a big attenuation effect with respect to a broadband sound can be obtained.
(Third embodiment)
A third embodiment of the present invention is shown in FIG. The third embodiment is an example in which the silencer of the first embodiment is configured by combining a plurality of panels.
[0028]
The panel 31 is a plate-like structure when viewed from the outside, and a plurality of air passages 34 extending in parallel are partitioned by a partition wall 38. Inside the partition wall 38, a plurality of Helmholtz resonators are formed which include a communication hole communicating with the air passage 34 and a cavity following the communication hole.
A convex portion 32 and a concave portion 33 are formed on the outer periphery of the panel 31, and the panel 31 can be jointed by fitting the convex portion 32 into the concave portion 33.
[0029]
According to the third embodiment of the present invention, silencers having various areas can be formed using one type of panel 31.
(Fourth embodiment)
A fourth embodiment of the present invention is shown in FIG. The fourth embodiment is an example in which the communication hole is formed only in the partition located above the air passage when the silencer is installed in the configuration of the first embodiment.
[0030]
The silencer 40 has a plurality of air passages 44 extending in parallel by partition walls 48. A cavity 47 divided by a partition plate 49 is formed inside the partition wall 48. The partition wall 48 is formed with a communication hole 46 communicating with the air passage 44 only at a position above the air passage 44 when the silencer 40 is installed.
According to the fourth embodiment of the present invention, when a silencer is used outdoors, there is an effect that water, dust, and the like hardly enter the cave portion of the Helmholtz resonator.
[0031]
(5th Example)
A fifth embodiment of the present invention is shown in FIG. The fifth embodiment is an example in which the shape of the partition wall is changed in the configuration of the first embodiment.
The silencer 50 has a plurality of air passages 54 extending in parallel by partition walls 58. Inside the partition wall 58, a plurality of Helmholtz resonators including a communication hole 56 communicating with the air passage 54 and a cavity 57 following the communication hole 56 are formed. The cross-sectional shape of the partition wall 58 is formed in a flow surface shape on the air inlet side and in a tail shape so as to prevent the vortex flow on the air outlet side.
[0032]
According to the fifth embodiment of the present invention, the cross-sectional shape of the partition wall 58 is a streamline type corresponding to the air flow direction, so that the air resistance can be further reduced as compared with the first embodiment.
(Sixth embodiment)
A sixth embodiment of the present invention is shown in FIG. The sixth embodiment is an example in which a silencer having the same structure as that of the first embodiment is attached to a vehicle. As shown in FIG. 12, a silencer 60 is attached as a radiator grille for a vehicle and an air intake for a bumper.
[0033]
The silencing characteristics of the silencer 60 using Helmholtz resonance are determined by the cross-sectional area and length of the neck, the volume of the sinus, and the cross-sectional area of the air passage 64. That is, if these are designed to a desired value, the external shape of the air passage, the neck, and the cave can be designed independently of the sound deadening characteristics. For this reason, for example, it is suitable as a silencer for use in a part where appearance shape is important, such as a radiator grill of a vehicle. If the external shape is the same as that of a conventional radiator grill or an air intake port of a panba, the silencer 60 can be installed without deteriorating the external appearance of the vehicle.
[0034]
As the application position of the silencer of the sixth embodiment of the present invention, it can be used as a member for openings such as a radiator, an air conditioner condenser and an under cover in addition to an air intake port of a radiator grill and a pump. Further, a silencing effect can be obtained even if a silencer is attached inside these openings. Since the silencer according to the first to fifth embodiments of the present invention can have a panel-like thin structure, it is advantageous when mounted at the above position of the vehicle. Since the silencer according to the sixth embodiment of the present invention has air permeability as described above, it is possible to reduce noise leaking from the opening of the engine room to the outside of the vehicle while ensuring the cooling performance of the radiator and the engine room. .
[0035]
(Seventh embodiment)
A seventh embodiment of the present invention is shown in FIG. The seventh embodiment is another example in which a silencer having the same structure as that of the first embodiment is attached to a vehicle. As shown in FIG. 13, a silencer 70 is attached as an air outlet louver for an air conditioner of a vehicle.
As an application position of the silencer 70, the silencer 70 may be used as a member in an air conditioner duct such as an air conditioner outlet louver of a vehicle or the like, or may be attached to an air conditioner outlet or an air conditioner duct. Thereby, the blowing sound of the air conditioner in a vehicle interior can be reduced.
[0036]
In the first to seventh embodiments of the present invention, the cross-sectional shape of the communication hole is circular. However, in the present invention, the cross-sectional shape of the communication hole may be oval, elliptical, polygonal, or the like. In the first to seventh embodiments of the present invention, the cross-sectional shape of the air passage is a quadrangle. However, in the present invention, the cross-sectional shape of the air passage may be a circle, an oval, a polygon, or the like. From the viewpoint of ventilation resistance, it is advantageous to use a polygonal shape such as a quadrangle or a hexagon because the cross-sectional area of the air passage can be increased.
[0037]
In the sixth and seventh embodiments of the present invention, the present invention is used as a silencer for a vehicle. However, the present invention is also suitable for a silencer used for a part that needs to obtain lighting such as a soundproof panel for construction. . The silencer of the present invention has an air passage unlike a normal sound insulation panel or sound insulation panel, and light is transmitted through the air passage together with air. For example, it is necessary to obtain lighting as a sound insulation panel for construction. Can be used. Furthermore, if the present invention is used as a soundproof panel for an expressway or a railway, it is a silencer that transmits light, so that a soundproof panel that can see the surrounding scenery can be obtained. At this time, if the silencer is made of a transparent resin material, further daylighting and light transmission can be achieved.
[Brief description of the drawings]
FIG. 1 shows a silencer according to a first embodiment of the present invention, and is a cross-sectional view taken along line II of FIG.
FIG. 2 is a perspective view showing a silencer according to a first embodiment of the present invention.
FIG. 3 is a perspective view showing a main part of the silencer according to the first embodiment of the present invention.
FIG. 4 is an explanatory diagram showing the principle of a Helmholtz resonator.
FIG. 5 is a characteristic diagram showing characteristics of a Helmholtz resonator.
FIG. 6 is a perspective view showing a silencer according to a second embodiment of the present invention.
7 is a cross-sectional view taken along line VII-VII in FIG.
FIG. 8 is a characteristic diagram showing a silencing characteristic of the silencer according to the second embodiment of the present invention.
FIG. 9 is a perspective view showing a silencer according to a third embodiment of the present invention.
FIG. 10 is a cross-sectional view showing a silencer according to a fourth embodiment of the present invention.
FIG. 11 is a cross-sectional view showing a silencer according to a fifth embodiment of the present invention.
FIG. 12 shows a sixth embodiment of the present invention and is a perspective view showing a state in which the silencer of the present invention is attached to a vehicle.
FIG. 13 shows a seventh embodiment of the present invention and is a perspective view showing a state in which the silencer of the present invention is attached to a vehicle.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Silencer 14 Air passage 15 Helmholtz resonator 16 Communication hole 17 Cavity 18 Bulkhead 19 Partition plate 31 Panel (silencer)
32 Convex part (bonding structure)
33 Concave part
100 Helmholtz Resonator 101 Neck 102 Cave 103 Air Passage 105 Wall 106 Cavity 107 Communication Hole

Claims (8)

A silencer having a plate-like portion and formed with a plurality of parallel air passages penetrating in the thickness direction,
A partition wall for partitioning adjacent air passages, the partition wall including a Helmholtz resonator having a cavity communicating with the air passage, and a cross-sectional shape of the air passage inlet portion or the air passage outlet portion of the partition wall is a curved surface Ri shape der, the Helmholtz resonator, the cavity, and comprises an outer wall having a communicating hole communicating with the air passage and the cavity, and the communication hole, the air passage during installation of the silencer A muffler characterized by being provided on the outer wall of the portion located above . The septum muffler of claim 1 Symbol mounting characterized by comprising the Helmholtz resonator at a position surrounding the air passages. 3. The silencer according to claim 1, wherein a resonance frequency of the Helmholtz resonator is different for each air passage unit communicating with the cavity. The silencer according to any one of claims 1 to 3 , wherein a cross-sectional shape of the air passage with respect to a direction perpendicular to the extending direction of the air passage is a polygonal shape. The silencer according to any one of claims 1 to 4 , wherein the silencer has a coupling structure capable of combining a plurality of the silencers on an outer periphery. The silencer according to any one of claims 1 to 5 , wherein the silencer is made of a transparent resin material. The silencer according to any one of claims 1 to 6 , wherein the silencer is provided in an opening of an engine room of a vehicle and on a front surface of a radiator. The silencer according to any one of claims 1 to 6 , wherein the silencer is attached to an air outlet of an air conditioner.

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