JP4175615B2 - Air vent silencer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a silencer for an air port provided in a cover that covers a noise source.
[0002]
[Prior art]
Air covers are installed in the vicinity of cooling devices such as radiators and oil coolers that are equipped with cooling fans in order to cool internal equipment, and cover the noise sources of engines and hydraulic equipment. In order to reduce noise, a silencer such as a sound absorbing blade or a sound absorbing ventilator is provided.
[0003]
FIG. 12 is a side sectional view of an engine room 50 of a wheel loader to which a sound absorbing ventilator is applied as a silencer, and FIG. 13 is a perspective view of the sound absorbing ventilator 53. The air port 51 is provided with a sound absorbing ventilator 53 having a rectangular parallelepiped container shape covering the air port 51 and having an opening 52 on the upper side surface. A sound absorbing material 54 is attached to the inner surface of the sound absorbing ventilator 53. The cooling air discharged from the air port 51 is changed in the direction of air flow at a substantially right angle in the sound absorption ventilator 53 and discharged to the outside from the opening 52 of the sound absorption ventilator 53, and the noise in the engine room 50 is reduced in the sound absorption ventilator 53. When leaving the inside, a part of the noise is absorbed by the sound absorbing material 54 and the noise leaking to the outside is reduced (see, for example, Patent Document 1).
[0004]
FIG. 14 is a plan sectional view of an engine room 60 of a wheel loader to which a sound absorbing blade 63 is applied as a silencer, and FIG. 15 is a side sectional view thereof. A plurality of plate-like sound-absorbing blades 63 each having a sound-absorbing material 64 attached to both surfaces form a ventilation path 65 at a predetermined interval so as not to restrict air flow excessively. It is arrange | positioned so that it may orthogonally cross. The cooling air passes through the ventilation path 65 between the sound absorbing blades 63, and the noise in the engine room 60 is partly absorbed by the sound absorbing material 64 when passing through the ventilation path 65 between the sound absorbing blades 63. Noise leaking to the outside is reduced (see, for example, Patent Document 2).
[0005]
[Patent Document 1]
JP 2000-220543 A (pages 4-5, FIGS. 1-2)
[Patent Document 2]
JP 2000-335260 A (pages 2 to 3, FIGS. 1 to 3)
[0006]
[Problems to be solved by the invention]
However, the above-described prior art has the following problems.
That is, in the sound absorption ventilator 53, the sound absorption effect is generally excellent, but the cooling air is discharged from the opening 52 of the ventilator 53 with the air direction changed substantially at right angles in the sound absorption ventilator 53, and the air port 51. On the other hand, since the opening 52 is narrow, the ventilation resistance is large and a sufficient cooling effect by the cooling device cannot be obtained. On the other hand, if the height (the left and right dimensions in FIG. 12) with respect to the air port 51 is increased in order to reduce the ventilation resistance, the amount of cooling air can be secured, but the size of the sound absorption ventilator 53 (the amount of protrusion) increases. At the same time, there arises a disadvantage that noise leaking from the opening 52 increases. Further, even if the ventilation resistance is reduced by providing an inclined surface on the end face of the sound absorbing material 54 attached to the sound absorbing ventilator 53, a sufficient effect is not obtained.
[0007]
Further, in the sound absorbing blade 63, the flow loss between the sound absorbing blades 63 in the ventilation path 65 is very small and excellent in ventilation. However, if the length of the ventilation path 65 (the left and right dimensions in FIG. 14) is short, ventilation is performed. Noise leaking from the path 65 increases. For this reason, in order to further reduce the noise,
(1) A method of lengthening the air passage 65, that is, a method of lengthening the width dimension (left and right dimensions in FIG. 14) of the sound absorbing blade 63. (2) A method of reducing the pitch between the sound absorbing blades 63 (narrowing the air passage 65). However, the method (1) causes a disadvantage that the size (projection amount) of the silencer increases. Further, according to the method (2), there arises a disadvantage that the ventilation resistance is increased and the air volume of the cooling air is insufficient.
[0008]
The present invention has been made paying attention to the above problems, and provides a silencer for an air port that is compact and has a low ventilation resistance and can sufficiently secure the air volume of cooling air and has an excellent noise reduction effect. The purpose is that.
[0009]
[Means, actions and effects for solving the problems]
In order to achieve the above object, according to a first aspect of the present invention, there is provided a silencer for an air port provided in a cover that covers a noise source and provided close to a fan in the cover, at least at a rotation center portion of the fan. of the air inlet including a portion facing said provided from the portion corresponding to the center of rotation of the fan so as to cover up part corresponding to the peripheral portion of the fan one radial preparative sound absorbing member on the inner surface while wearing a sound absorbing ventilator having an opening on the outer peripheral side surface portion of said one radially plate having a plurality arranged substantially perpendicular to the air outlet in a portion other than the portion covered with sound-absorbing ventilator of the air inlet And a sound absorbing means each having a sound absorbing member attached to the mutually facing surfaces.
[0010]
According to the above configuration, the air inlet including a portion facing the rotation center of the fan, the air opening until a portion corresponding to the peripheral portion of the fan one radially from a portion corresponding to the rotation center of the fan by covering a narrower sound absorbing ventilator than the width, a small site while reducing effectively noise by the sound-absorbing ventilator (rotation center of the fan) of the wind speed, the greater part of the wind speed (peripheral portion of the fan), the air inlet The sound absorption means having a small ventilation resistance substantially orthogonal to the above compensates for the air volume loss caused by the sound absorption ventilator, so that it is possible to obtain a silencer that satisfies the noise reduction amount of the entire air port and the air volume of the cooling air.
[0011]
Further, according to a second invention based on the first invention, the sound absorbing ventilator further includes a periphery of one of the fans in a radial direction orthogonal to the one radial direction from a portion corresponding to the rotation center of the fan. It is set as the structure provided so that the part corresponding to a part might also be covered .
Further, according to a third invention based on the first invention, the sound absorbing ventilator further corresponds to a peripheral portion of the fan in a diametrical direction perpendicular to the one radial direction from a portion corresponding to the rotation center portion of the fan. It is set as the structure provided so that even a part might be covered.
According to the above configuration, the sound absorption ventilator having an excellent sound absorption effect is provided in the portion including the rotation center portion of the fan having a low wind speed, and the noise including the noise in the center portion of the fan, which is a large noise equivalent to the peripheral portion of the fan, is efficiently performed. In addition to a good reduction, a sound absorbing means having excellent ventilation is provided in the periphery of the fan having a high wind speed to ensure a sufficient amount of cooling air. As a result, the sound absorption means compensates for the decrease in the air volume of the cooling air by the sound absorption ventilator, the desired air volume of the cooling air as the entire air port can be secured, and the sound absorption ventilator compensates for the shortage of noise reduction by the sound absorption means. A desired noise reduction effect in the entire mouth can be obtained, and as a result, a silencer for an air mouth having a low ventilation resistance and an excellent noise reduction effect can be obtained.
[0012]
According to a fourth invention based on the first , second or third invention, a part of the plate of the sound absorbing means also serves as a part of the outer peripheral side surface of the sound absorbing ventilator.
According to the said structure, while the structure of a silencer is simplified and it becomes low-cost, ventilation cross-sectional area increases, ventilation resistance becomes small, and it can increase the air volume of cooling air.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments will be described in detail with reference to the drawings.
[0014]
As shown in FIG. 1, an air port 3 is provided in a side wall 2 of an engine room cover 1 of a wheel loader, and a radiator 5 in which a fan 4 is arranged in parallel is disposed near the inside of the air port 3. . The rotation center of the fan 4 is a position corresponding to the central portion of the air port 3, and a sound absorbing ventilator 10 covering the lower side from the central portion of the air port 3 is mounted on the outside of the side wall 2. A plurality of sound absorbing blades 20 are juxtaposed above 10 so as to cover the remaining portion of the air port 3 as sound absorbing means for the remaining portion of the air port 3.
[0015]
As shown in FIGS. 2 and 3, the sound-absorbing ventilator 10 has a width slightly larger than the width of the air port 3 and is separated from the side wall 2 by a predetermined distance L1 so as to cover the lower part from the center of the air port 3. The panel 11 is provided in the shape of a rectangular parallelepiped container, and the side plates 2, 12, and 13 are provided on the side walls 2, respectively. It is fixed to. An opening 14 is formed at the lower end of the sound absorbing ventilator 10 by the panel 11, left and right side plates 12, 12 and the side wall 2. In addition, sound absorbing materials 15, 16, 16, and 17 are attached to the inside of the panel 11 and the side plates 12, 12, and 13.
[0016]
The sound-absorbing blade 20 having a flat plate shape is formed so that the air port 3 is substantially orthogonal to the air port 3 in the portion (the upper portion of the air port 3) of the air port 3 that is not covered by the sound-absorbing ventilator 10. It straddles between the side plates 28 and 28 respectively arranged at the extended positions of the left and right side plates 12 and 12 of the sound absorbing ventilator 10, and a plurality of them are arranged in parallel at substantially equal intervals.
As shown in FIG. 4, the sound absorbing blade 20 includes a plate-shaped core member 21 provided with attachment portions 21 a and 21 a at both left and right ends, and a sound absorbing member 22 attached to both surfaces of the core member 21 over substantially the entire surface. 22 and semi-cylindrical covers 23, 23 that cover the end surfaces of the sound absorbing materials 22, 22 that are respectively provided and adhered to both ends in the ventilation direction.
[0017]
Next, the operation according to the above configuration will be described.
Cooling air and noise coming out from the lower part including the central part of the air port 3 are discharged to the outside through the opening 14 that opens downward through the inside of the sound absorption ventilator 10. Further, the cooling air and noise emitted from the upper part of the air port 3 pass between the sound absorbing blades 20 and are released to the outside. While the noise passes through these paths, a part of the noise is absorbed by the sound absorbing materials 15, 16, 16, 17 of the sound absorbing ventilator 10 or the sound absorbing material 22 of the sound absorbing blade 20, and the noise emitted to the outside is reduced.
[0018]
The effect by this embodiment is demonstrated.
As shown in FIG. 5, the distribution of the wind speed at the air port 3 due to the rotation of the fan 4 is smaller in the central part and larger in the peripheral part. Further, the noise distribution in the vicinity of the fan 4 is somewhat larger in the vicinity of the fan 4, but the noise in the air port 3 is a substantially averaged distribution.
In the present embodiment, a sound absorbing ventilator 10 having an excellent sound absorbing effect is provided in a portion including the central portion of the air port 3 where the wind speed is low, and the noise in the central portion of the fan 4, which is a large noise equivalent to the peripheral portion of the fan 4, is provided. In addition to efficiently reducing the noise included, a sound absorbing blade 20 having excellent ventilation is provided in parallel above the air port 3 where the wind speed is high, so that a sufficient amount of cooling air is secured. As a result, the sound absorption blade 20 compensates for the decrease in the air volume of the cooling air by the sound absorption ventilator 10, and a desired amount of cooling air can be secured as the entire air port 3, and the sound absorption ventilator 10 lacks the amount of noise reduction by the sound absorption blade 20. Therefore, it is possible to obtain a desired noise reduction effect in the entire air port 3, and thus it is possible to obtain a silencer having a small ventilation resistance and an excellent noise reduction effect.
Further, by appropriately selecting the number, size and arrangement of the sound absorbing blades 20, the shape of the sound absorbing ventilator 10, etc., a sufficient air volume and noise reduction amount can be obtained in a well-balanced space in a limited space as the entire silencer.
Further, since the unitized sound absorbing blades 20 are juxtaposed as the sound absorbing means of the portion of the air port 3 that is not covered by the sound absorbing ventilator 10, the parts can be shared and the cost can be reduced.
[0019]
In addition, this invention is not limited to the said embodiment, You may add a change and correction within the scope of the present invention.
For example, although an example in which a plurality of sound absorbing blades 20 are arranged side by side on the upper side of the sound absorbing ventilator 10 has been described, as shown in FIG. 6A, an air absorbing ventilator 10A narrower than the width of the air port 3 is used. A plurality of sound absorbing blades 20A perpendicular to the air port 3 along the vertical direction may be provided at one end in the width direction of the lower air port 3 including the center of the port 3 (the right side in FIG. 6A). As shown in FIG. 6 (b), the sound absorption ventilator 10 </ b> B narrower than the width of the air port 3 is used, and the widthwise ends of the lower air port 3 including the central portion of the air port 3 are respectively used. A plurality of sound absorbing blades 20B perpendicular to the air port 3 may be provided along the vertical direction.
Further, not only the flat sound absorbing blade but also U-shaped sound absorbing blades 20C ₁ , 20C ₂ ,... Having curved surfaces as shown in FIG. A sound-absorbing ventilator 10C having a letter shape may be provided. In this case, the air outlet 3C is a U-shape along the sound-absorbing blade 20C _1. Further, as shown in FIG. 7 (b), a sound absorbing ventilator 10D whose outer peripheral side surface has a kokeshi shape may be provided at the center using C-shaped sound absorbing blades 20D ₁ , 20D ₂ ,. In this case, the air inlet 3D is a circular along the sound-absorbing blade 20D _1.
Furthermore, although the opening part of the sound absorption ventilator is an example facing downward, it may be opened upward or may be configured to open in either the left or right direction.
[0020]
As described above, it is possible to increase the air volume of the cooling air by disposing the sound absorbing blade having excellent air permeability in the portion of the air port corresponding to the peripheral portion of the fan 4 where the air velocity is high. Therefore, when the air volume may be reduced, it is possible to reduce the external size of the fan or slow down the fan speed, and to reduce the noise from the fan. Further, when changing the radiator in response to an increase in the air volume, it is possible to employ a radiator having a smaller size or a coarser fin pitch, and it is possible to reduce the size of the apparatus and reduce the cost.
[0021]
In the above embodiment, the sound absorbing ventilator and the sound absorbing blade are independent from each other. However, as shown in FIG. 8, the sound absorbing blade may also serve as a part of the components of the sound absorbing ventilator. The sound absorbing ventilator may also serve as a part of the components of the sound absorbing blade.
That is, the sound absorbing ventilator 10E having the opening 14 on the lower side does not include the side plate (corresponding to the side plate 13 in FIG. 1) at the upper end, and is the lowermost side of the sound absorbing blade 20 disposed above the sound absorbing ventilator 10E. core material 21 _n of the noise absorbing blade 20 _n also serves as an upper side plate of the sound absorption ventilator 10E, the lower the sound absorbing member 22 _n of the noise absorbing blade 20 _n also serves as the upper sound-absorbing material of the sound absorbing ventilator 10E. Further, a sound absorbing material 18E facing the sound absorbing blade 20A is attached to the right side plate 12E of the sound absorbing ventilator 10E, and a semi-cylinder that covers the end surfaces of the sound absorbing materials 16E and 18E at the end on the air port 3 side. A cover 23E having a shape is attached.
[0022]
According to this, the structure of the silencer is simplified and the cost is reduced, and the ventilation cross-sectional area is increased, the ventilation resistance is reduced, and the air volume of the cooling air can be increased.
Note that FIG. 8 is an example corresponding to the mode of FIG. 6A, and it is needless to say that it can be applied to other modes.
[0023]
In the above embodiment, as described with reference to FIG. 4, the unitized sound absorbing blades are used in parallel. However, it is not always necessary to use only the unitized sound absorbing blades. For example, as an example corresponding to the embodiment of FIG. 1, instead of the three sound absorbing blades 20 arranged side by side, as shown in FIG. 9A, the second sound absorbing blade 20 is arranged. Above the sound absorbing blade 20, a sound absorbing material 26 attached to the lower surface of the plate 25 provided substantially orthogonal to the opening 3 is disposed at the upper end of the opening 3, and below the sound absorbing blade 20. The sound absorbing material 19 may be arranged to be attached to the upper surface of the side plate 13 at the upper end of the sound absorbing ventilator 10. In this case, the side plate 13 also serves as a plate (a sound absorbing member is attached) of sound absorbing means provided in the remaining portion of the air port 3 covered by the sound absorbing ventilator 10. Furthermore, as shown in FIG. 9B, the sound absorbing blade 20 may be omitted if the noise reduction amount and the air volume are satisfied with respect to the configuration of FIG. 9A. Thereby, waste such as providing unnecessary sound absorbing material (for example, the sound absorbing material 22 _{H in} FIG. 3) on the outer peripheral side surface of the silencer can be prevented, and the manufacturing time can be shortened.
[0024]
In addition, as an example in which a plurality of sound absorbing blades 20 are provided as plate-like sound absorbing means arranged in parallel with the sound absorbing ventilator 10, as shown in FIG. 10, the plate 81 in which both ends in the short direction are bent at a slightly acute angle is used. The sound absorbing material 82 may be attached inside, and a plurality of sound absorbing louvers 80 provided in parallel may be provided in parallel to the sound absorbing ventilator 10.
[0025]
Of the sound absorbing materials 15, 16, and 17 inside the sound absorbing ventilator 10, the sound absorbing material may not be provided inside the outer peripheral side plates 12, 12, and 13.
Moreover, the cover which covers the end surface of the sound absorbing blade is not limited to a semi-cylindrical shape, and may be a plane perpendicular to the core material, or may be a straight diagonal shape or a mountain shape.
Also, the end shape of the sound absorbing louver may not be a bent acute angle straight line, but may be an arc shape or a curved line.
[0026]
Furthermore, although the description has been given of the example in which the portion where the sound absorbing blade or the sound absorbing louver is provided and the sound absorbing ventilator are made close to each other, they may be configured separately from each other.
As the sound absorbing material, foamed resin such as urethane foam or fibrous PET may be used, or glass wool or felt may be used.
[0027]
Moreover, although it demonstrated in the example of the exhaust port provided with the extrusion type fan as an air port, it cannot be overemphasized that it can apply to the intake port provided with the suction type fan, and also in any of an exhaust side and an intake side. The fan may be applied to an air port that is not arranged in the vicinity. For example, as shown in FIG. 11, the present invention can also be applied to an intake port in which an extrusion fan is not disposed in the vicinity. In this case, a sound absorbing means such as a sound absorbing blade 20 or a sound absorbing louver having excellent air permeability may be disposed at a portion of the air inlet having a large wind speed by the fan 4, and a sound absorbing ventilator 10 having an excellent sound absorbing effect may be provided at a portion having a low wind speed. Needless to say. FIG. 11 shows an example in which the sound absorbing means and the sound absorbing ventilator 10 are separated from each other, but the present invention is not limited to this.
[0028]
Furthermore, although the embodiment has been described with an example of an air port in which the radiator 5 is provided side by side, the presence or absence of the radiator is not limited as long as the air port has a wind speed distribution as described with reference to FIG.
Although it demonstrated in the example applied to the air port of the engine room of a wheel loader, you may apply to the air port of the engine room of other work vehicles, and other than a vehicle, for example, the power generator and air which installed the engine in parallel You may apply this invention to the cover of a compressor. Of course, the present invention may be applied to a noise source other than the engine, for example, an air port of a cover that covers a hydraulic device.
[0029]
As described above, according to the present invention, a part of the air opening including the portion facing the rotation center of the fan is covered with the sound absorbing ventilator, and the sound absorbing blade having a predetermined shape, arrangement, number of sheets is provided in the remaining part of the air opening. Is installed perpendicularly to the air port, noise can be efficiently reduced by a sound-absorbing ventilator at a part where the wind speed is low, and a sufficient amount of cooling air can be secured at a part where the wind speed is high. The air volume and noise reduction effect can be obtained.
In addition, by appropriately selecting the number, size, and arrangement of the sound absorbing blades, the shape of the sound absorbing ventilator, and the like, a desired cooling air flow rate and noise reduction amount can be obtained. Thereby, as a whole silencer, sufficient air volume and a noise reduction effect can be obtained with sufficient balance in a limited space.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a silencer according to an embodiment.
FIG. 2 is a view taken in the direction of arrow Z in FIG.
FIG. 3 is a perspective view of the silencer according to the embodiment.
FIG. 4 is an exploded perspective view of the sound absorbing blade according to the embodiment.
FIG. 5 is an explanatory diagram of noise distribution and wind speed distribution according to the embodiment.
FIG. 6 is a front view of a silencer according to another embodiment.
FIG. 7 is a front view of a muffler according to another embodiment.
FIGS. 8A and 8B are diagrams of a silencer according to another aspect, in which FIG. 8A is a front view, FIG. 8B is a cross-sectional view taken along line AA in FIG. 8A, and FIG. .
FIG. 9 is a cross-sectional view of a silencer according to another embodiment.
FIG. 10 is a cross-sectional view of a silencer according to another embodiment.
FIG. 11 is a cross-sectional view of a silencer according to another embodiment.
FIG. 12 is a cross-sectional view of a silencer according to the prior art.
FIG. 13 is a perspective view of a silencer according to the prior art.
FIG. 14 is a plan sectional view of a silencer according to the prior art.
FIG. 15 is a side sectional view of a silencer according to the prior art.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Engine room cover, 2 ... Side wall, 3 ... Air inlet, 4 ... Fan, 5 ... Radiator, 10 ... Sound absorption ventilator, 11 ... Panel, 14 ... Opening part, 15, 16, 17, 22 ... Sound absorption material, 20 ... Sound absorbing blade (plate-like sound absorbing means), 21... Core material (plate).

Claims (4)

In the silencer of the air port provided on the cover that covers the noise source and close to the fan in the cover,
A peripheral portion of the fan (4) in a radial direction from a portion corresponding to the rotation center portion of the fan (4) of the air port (3) including at least a portion facing the rotation center portion of the fan (4) provided so as to cover up a portion corresponding to the inside surface as well as attaching the sound absorbing member (15), and sound absorbing ventilator (10) having an opening (14) in the peripheral side face of the one radial,
The sound absorbing members are respectively provided on the mutually opposing surfaces of a plurality of plates (21) arranged in parallel to the air port (3) at portions other than the portion covered with the sound absorbing ventilator (10) of the air port (3). (22) A sound-absorbing device for an air port, comprising sound-absorbing means (20) attached thereto. In the silencer of the air mouth of Claim 1,
The partial sound absorbing ventilator (10) further corresponding to the peripheral portion of the fan (4) one of the fan from the portion corresponding to the rotation center of the radial direction perpendicular to the one radial direction (4) A muffler for an air port, characterized in that it is provided so as to cover the air. In the silencer of the air mouth of Claim 1,
The sound absorbing ventilator (Ten) Furthermore, the fan (Four) The fan in the diametrical direction perpendicular to the one radial direction from the portion corresponding to the rotation center portion of (Four) It was provided to cover even the part corresponding to the periphery of
A muffler for an air outlet, characterized by that. In the silencer of the air mouth of Claim 1, 2, or 3 ,
A silencer for an air port, wherein a part of plates (21 _n ) of the sound absorbing means (20 _n ) also serves as a part of an outer peripheral side surface of the sound absorbing ventilator (10E).

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