JP7233341B2 - weather cover - Google Patents

Description

The present invention relates to a weather cover that is attached to the outer wall of a building and prevents rainwater from entering.

In a building such as a house or a factory, a weather cover is attached corresponding to the opening of the ventilation fan, and the weather cover prevents wind, rain, etc. from entering through the opening (see, for example, Patent Document 1). Such a weather cover suppresses the entry and exit of noise through the ventilation passage by attaching a sound absorbing material made of a porous material to the inner wall surface of the ventilation passage.

Japanese Patent No. 4741889

If the sound absorbing material is provided on the inner wall surface of the ventilation passage as in Patent Document 1, the sound absorbing material increases the ventilation resistance of the ventilation passage, causing problems such as the occurrence of wind noise and an increase in the load on the ventilation fan. There is a risk.

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems associated with the prior art, and has been proposed to preferably solve these problems. With the goal.

In order to overcome the above problems and achieve the intended purpose, the weather cover according to the present invention is
A weather cover having an air flow passage through which air flows between a first opening that opens rearward and connects to the ventilation fan side and a second opening that opens downward,
a first damping section having a first reflecting wall provided opposite to the first opening and formed to protrude forward from the front wall section;
a second damping section having a second reflection wall provided opposite to the second opening and formed to protrude upward from the upper wall section;
a circulation member that is installed inside the weather cover from the upper wall portion to the front wall portion so as to cover the air circulation passage side of the first damping portion and the second damping portion, and is capable of transmitting sound;
The gist is that the dimension of the second reflecting wall that projects upward from the upper wall is set larger than the dimension of the first reflecting wall that projects forward from the front wall.

According to the weather cover of the present invention, air can be smoothly circulated, and noise can be prevented from entering and exiting.

1 is a schematic perspective view showing a weather cover according to an embodiment of the present invention; FIG. 1 is a longitudinal sectional view showing a weather cover of an embodiment; FIG. 1 is a schematic perspective view showing an exploded weather cover of an embodiment; FIG. It is explanatory drawing which shows the assembly process of the weather cover of an Example. It is a graph which shows the test result which confirmed the noise reduction effect. FIG. 11 is a vertical cross-sectional view showing a weather cover of a modified example;

BEST MODE FOR CARRYING OUT THE INVENTION Next, the weather cover according to the present invention will be described below with reference to preferred embodiments and with reference to the accompanying drawings. The weather cover is attached to the outer wall of the building so as to cover the opening of the ventilation fan provided on the outer wall of the building. In the following description, the exterior wall side of the building to which the weather cover is attached is referred to as the rear, and the side opposite to the exterior wall is referred to as the front.

As shown in FIG. 2, the weather cover 10 according to the embodiment opens downward by guiding downward the air that flows forward from the first opening 14 that opens rearward and connects to the ventilation fan side. It has an air flow passage 12 that discharges to the outside from a second opening 16 . The weather cover 10 is connected to the upper edge of the first opening 14 and forms an upper surface on the upstream side of the air flow passage 12. The weather cover 10 is connected to the lower edge of the first opening 14 and forms the air flow passage. 12 and a lower wall portion 20 forming the lower surface on the upstream side of the lower wall portion 20 . In addition, the weather cover 10 continues to the front edge of the second opening 16 to form a front wall portion 22 that constitutes the front surface on the downstream side of the air flow passage 12, and continues to the rear edge of the second opening 16 to provide air flow. and a rear wall portion 24 forming a rear surface on the downstream side of the flow passage 12 . Furthermore, the weather cover 10 is provided with lateral wall portions 26 that are connected to the left and right side edges of the first opening portion 14 and the second opening portion 16, respectively, and constitute the side surfaces of the air flow passage 12 from the upstream side to the downstream side. there is The weather cover 10 is made of metal such as stainless steel or aluminum, synthetic resin such as polypropylene, or the like, either alone or in combination.

As shown in FIG. 2 , the weather cover 10 is provided with a first damping portion 28 formed to protrude forward from the front wall portion 22 at a position facing the first opening portion 14 . The first attenuation section 28 has a first reflection wall 28a provided facing the first opening 14 . The first reflecting wall 28a is provided perpendicularly or substantially perpendicularly to the direction of air circulation in the first opening 14. As shown in FIG. In the weather cover 10, the direction along the upstream side of the air flow passage 12 defined by the upper wall portion 18, the lower wall portion 20, and the left and right lateral wall portions 26, 26 (=the direction of the air when passing through the first opening 14) ) mainly reaches the first damping section 28 . Therefore, by making the first reflecting wall 28a orthogonal or substantially orthogonal to the direction of air circulation in the first opening 14, the sound passing along the upstream side of the air circulation passage 12 is reflected by the first reflecting wall 28a. It hits at an angle that is orthogonal or nearly orthogonal. The first reflecting wall 28 a of the embodiment is provided so as to extend parallel to the opening surface of the first opening 14 . Also, the first reflecting wall 28a is formed to have a size equal to or larger than the opening area of the first opening 14. As shown in FIG.

As shown in FIG. 2 , the weather cover 10 is provided with a second damping portion 30 formed to protrude upward from the upper wall portion 18 at a position facing the second opening portion 16 . The second attenuation section 30 has a second reflection wall 30a provided facing the second opening 16 . The second reflecting wall 30 a is provided so as to be orthogonal or substantially orthogonal to the direction of air circulation in the second opening 16 . In the weather cover 10, the direction along the downstream side of the air flow passage 12 defined by the front wall portion 22, the rear wall portion 24, and the left and right lateral wall portions 26, 26 (=the direction of the air when passing through the second opening 16) ) will mainly reach the second damping section 30 . Therefore, by making the second reflecting wall 30a orthogonal or substantially orthogonal to the direction of air circulation in the second opening 16, the sound passing along the downstream side of the air circulation passage 12 is reflected by the second reflecting wall 30a. It hits at an angle that is orthogonal or nearly orthogonal. The second reflecting wall 30 a of the embodiment is provided so as to extend parallel to the opening surface of the second opening 16 . Also, the second reflecting wall 30a is formed to have a size equal to or larger than the opening area of the second opening 16. As shown in FIG.

As shown in FIG. 2, in the weather cover 10, the upward projection dimension L2 of the second reflecting wall 30a in the second attenuation section 30 from the upper wall section 18 is equal to the length of the first reflecting wall 28a in the first attenuation section 28. It is set larger than the projection dimension L1 from the front wall portion 22 to the front side. For example, the projection dimension L1 of the first reflecting wall 28a is set to 20 mm to 25 mm, while the projection dimension L2 of the second reflecting wall 30a is set to 40 mm to 60 mm.

As shown in FIG. 2 , the weather cover 10 extends from the upper wall portion 18 to the front wall portion 22 so as to cover the openings of the first damping portion 28 and the second damping portion 30 connected to the air flow passage 12 . It has a flow member 32 installed in. Thus, in the weather cover 10, the first damping portion 28, the second damping portion 30, and the air flow passage 12 are separated by the flow member 32 curved in an arc with the left-right direction as the axis. The circulation member 32 is installed so that its upper edge contacts the rear edge of the second damping section 30 and its lower edge contacts the lower edge of the first damping section 28 . Further, the right and left side edges of the circulation member 32 are brought into contact with the inner surfaces of the lateral wall portions 26 respectively.

As shown in FIGS. 1 and 2, the weather cover 10 has a first space 34 between the circulation member 32 and the first reflection wall 28a of the first damping section 28 provided on the front side of the circulation member 32. is formed. In the weather cover 10 , a second space 36 is formed between the circulation member 32 and the second reflection wall 30 a of the second damping section 30 provided above the circulation member 32 . In the first space portion 34 (inside the first damping portion 28) and the second space portion 36 (inside the second damping portion 30), for example, no sound absorbing material or the like is arranged, and only air exists. In the weather cover 10, the front-to-rear distance between the first reflecting wall 28a and the circulation member 32 is set relatively narrow, and the front-to-rear dimension of the first space 34 is relatively narrow. In the weather cover 10, the vertical interval between the second reflecting wall 30a and the circulation member 32 is set wider than the front-to-back interval between the first reflecting wall 28a and the circulation member 32, so that the vertical dimension of the second space 36 is is relatively wide.

The circulation member 32 is configured to allow transmission of sound. The circulation member 32 uses a material that is permeable to sound but has relatively low air permeability. As the flow member 32, a nonwoven fabric, a foam such as polyurethane foam, a mesh material such as metal, or the like can be used. The circulation member 32 preferably has a ventilation rate in the range of 150 cm ³ /cm ² ·S to 350 cm ³ /cm ² ·S. When the air permeability of the circulation member 32 is within the range described above, the internal noise from the ventilation fan side entering through the first opening 14 and the external noise entering through the second opening 16 are transmitted through the circulation member 32 to the air circulation path. 12 to spaces 34 and 36 as appropriate. On the other hand, if the air permeability of the circulation member 32 is within the range described above, the air flowing in from the first opening 14 in the air circulation passage 12 is properly guided by the circulation member 32 toward the second opening 16. can do.

When the circulation member 32 is made of, for example, a nonwoven fabric, the permeation amount can be adjusted by the basis weight of the nonwoven fabric. Specifically, when setting the thickness of the nonwoven fabric to 0.2 mm, it is preferable to set the weight per unit area of the nonwoven fabric within the range of 25 g/m ² to 30 g/m ² . By setting the basis weight of the nonwoven fabric within the range described above, it is possible to achieve both the passage of noise and the guidance of air, which is preferable.

As shown in FIGS. 3 and 4, the weather cover 10 is configured by combining an installation member 38 attached to the outer wall of the building, a body member 40 attached to the installation member 38, and the circulation member 32. As shown in FIG. The installation member 38 is a plate-like body in which the first opening 14 is formed. The installation member 38 has support portions 42 provided to protrude forward from the left and right opening edges of the first opening 14 in accordance with the curvature of the air flow passage 12 . The flow member 32 is mounted across the left and right support portions 42 , 42 . The body member 40 is formed in a box shape. Also, the body member 40 is provided with a first damping portion 28 and a second damping portion 30 . The main body member 40 is detachably assembled with the installation member 38 by inserting the support portions 42, 42 to which the flow member 32 is attached through an opening formed in alignment with the first opening portion 14 inside. As a result, the upper edge of the circulation member 32 supported by the support portion 42 is brought into contact with the vicinity of the rear edge of the opening of the second attenuation section 30, and the lower edge of the circulation member 32 is brought into contact with the vicinity of the lower edge of the opening of the first attenuation section 28. placed. In the weather cover 10 , the side edge of the circulation member 32 abuts the lateral wall portion 26 to define the air circulation passage 12 .

As shown in FIG. 2 , in the weather cover 10 , internal noise from a ventilation fan or the like entering through the first opening 14 passes through the circulation member 32 and is reflected by the first reflecting wall 28 a facing the first opening 14 . do. As a result, the internal noise can be reduced by canceling out the reflected noise having a phase difference with the internal noise. Similarly, in the weather cover 10 , external noise entering through the second opening 16 passes through the circulation member 32 and is reflected by the second reflection wall 30 a facing the second opening 16 . As a result, the external noise can be reduced by canceling out the reflected noise having a phase difference with the external noise. Therefore, the weather cover 10 can prevent internal noise from leaking to the outside through the second opening 16 and can prevent external noise from entering the building through the first opening 14 . Since the circulation member 32 is not required to have sound absorbing properties, it is difficult for moisture or oil to be taken in, and deterioration of the circulation member 32 can be suppressed. Moreover, since the reflecting walls 28a and 30a are less likely to deteriorate like the sound absorbing material, the noise reduction effect can be maintained for a long period of time.

In the weather cover 10, the upward projection dimension L2 of the second reflecting wall 30a from the upper wall portion 18 is set to be larger than the forward projection dimension L1 of the first reflecting wall 28a from the front wall portion 22. . The internal noise, which is mainly caused by the wind noise of the ventilation fan, is dominated by sounds of 2 kHz to 4 kHz. can be formed. In addition, external noise is predominantly sound with a frequency around 1 kHz, which is lower than the internal noise. , can form reflected noise with a moderate phase difference. In this way, the weather cover 10 sets the positions of the reflecting walls 28a and 30a according to the respective characteristics of the internal noise entering through the first opening 14 and the external noise entering through the second opening 16. Therefore, both internal noise and external noise can be preferably reduced.

In particular, by providing the first reflecting wall 28a so as to be orthogonal or substantially orthogonal to the air circulation direction in the first opening 14, the internal noise and the reflected noise reflected by the first reflecting wall 28a can be effectively can cancel each other out. Similarly, by providing the second reflecting wall 30a so as to be orthogonal or substantially orthogonal to the air flow direction in the second opening 16, the external noise and the reflected noise reflected by the second reflecting wall 30a can be effectively can cancel out.

The weather cover 10 is configured by a circulation member 32 installed inside from the upper wall portion 18 to the front wall portion 22 so as to cover the air circulation passage 12 side of the first damping portion 28 and the second damping portion 30 . and the first damping section 28 and second damping section 30 sides. Since the circulation member 32 covers the first damping portion 28 and the second damping portion 30 that protrude to the outside in this manner, the pressure loss of the air flowing through the air flow passage 12 can be suppressed. Further, although the circulation member 32 is required to transmit noise, it is not required to have sound absorbing properties, so the air permeability can be set relatively low. Therefore, the air flowing through the air circulation passage 12 can be smoothly guided by the circulation member 32 .

According to the weather cover 10, both the property of air as a viscous gas and the property of sound as a dilatational wave are preferably used to reduce both internal noise and external noise and to facilitate smooth air flow. can be compatible.

The weather cover 10 has a configuration in which the circulation member 32 is attached to the support portion 42 projecting from the installation member 38, so that when the installation member 38 and the main body member 40 are combined, the circulation member 32 can be installed inside the main body member 40. can be done. That is, it is possible to avoid the work of attaching the circulation member 32 inside the box-shaped main body member 40, and the manufacturing of the weather cover 10 can be simplified. In addition, by removing the body member 40 of the weather cover 10, the circulation member 32 can be exposed, which facilitates maintenance such as cleaning and replacement of the circulation member 32. FIG.

A weather cover of a test example and a weather cover of a reference example having the same size and shape of the first opening, the second opening and the airflow passage were prepared, and the noise reduction effect was measured. The weather cover of the test example corresponds to the configuration described in the example, and the overhang dimension L1 from the front wall of the first reflecting wall is set to 25 mm, and the overhang from the upper wall of the second reflecting wall The dimension L2 is set to 40 mm. Note that the weather cover of the reference example has a general shape that does not include a damping portion.

For the test example and reference example, white noise is injected from the first opening and the sound pressure level is measured at the second opening to determine how much the outdoor sound (internal noise), which is the noise leaking from the inside to the outside, is measured. Check if it can be reduced. Similarly, for the test example and the reference example, white noise was incident from the second opening, and the sound pressure level was measured at the first opening. to see how much it can be reduced. The results are shown in FIG.

As shown in FIG. 5, it can be seen that the sound pressure level of the weather cover of the test example is significantly lower near 3 kHz than that of the reference example. The internal noise, which is mainly caused by the noise of the ventilation fan, is dominated by sounds of 2 kHz to 4 kHz, so it can be confirmed that the weather cover of the test example can greatly reduce the internal noise (outdoor sound). It can be seen that the sound pressure level of the weather cover of the test example is greatly lowered in the vicinity of 1 kHz compared to the reference example. Since the sound around 1 kHz is dominant in external noise, it can be confirmed that the weather cover of the test example can greatly reduce the external noise (room sound).

(Change example)
The configuration is not limited to that described above, and for example, the following configuration may be used.

(1) As shown in FIG. 6, the first damping portion 28 may be formed up to the front side of the second opening portion 16 . In this case, the opening edge on the front side of the second opening 16 becomes the front wall portion 22 . Also, the second damping portion 30 may be formed up to the upper side of the first opening portion 14 . In this case, the upper opening edge of the first opening 14 becomes the upper wall portion 18 .

(2) In the embodiment, the structure in which the air flows from the first opening to the second opening was described. good.

10 weather cover, 12 air flow passage,
14 first opening, 16 second opening, 18 upper wall, 22 front wall, 28 first damping portion,
28a first reflecting wall, 30 second attenuation section, 30a second reflecting wall, 32 circulation member,
38 installation member, 40 body member, 42 support part,
L1 Overhang dimension from the front wall of the first reflecting wall,
L2 Overhang dimension from the upper wall of the second reflecting wall

Claims (4)

A weather cover having an air flow passage through which air flows between a first opening that opens rearward and connects to the ventilation fan side and a second opening that opens downward,
a first damping section having a first reflecting wall provided opposite to the first opening and formed to protrude forward from the front wall section;
a second damping section having a second reflection wall provided opposite to the second opening and formed to protrude upward from the upper wall section;
a circulation member that is installed inside the weather cover from the upper wall portion to the front wall portion so as to cover the air circulation passage side of the first damping portion and the second damping portion, and is capable of transmitting sound;
The weather cover is characterized in that a dimension of the second reflection wall projecting upward from the upper wall is set larger than a dimension of the projecting front side of the first reflection wall from the front wall. . The first reflecting wall is provided so as to be orthogonal or substantially orthogonal to the air flow direction in the first opening,
2. The weather cover according to claim 1, wherein the second reflecting wall is provided so as to be orthogonal or substantially orthogonal to the direction of air circulation in the second opening. 3. The weather cover according to claim 1, wherein the circulation member has a ventilation rate in the range of 150 cm ³ /cm ² ·S to 350 cm ³ /cm ² ·S. an installation member provided with the first opening and attached to an outer wall of a building;
a body member provided with the first damping portion and the second damping portion and attached to the installation member;
The installation member has support portions provided to protrude forward from left and right opening edges of the first opening in accordance with the curvature of the air flow passage,
The weather cover according to any one of claims 1 to 3, wherein the circulation member is mounted across the left and right support portions.

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