JP2011237078A - Sound insulation vent cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound insulation vent cap effectively reducing external noise while securing a required a ventilation passage.SOLUTION: A sound adsorption body 13 provided in a body 11 of the sound insulating vent cap 10 is constituted of an attaching member 13a comprising a plate material having many through holes and a sound adsorption material 13b pasted on the attaching member 13a and comprising unwoven fabric. The sound adsorption body 13 is arranged outside a tubular virtual ventilation path K connecting a ventilation port 15 to an air inlet 14. An air layer 16 is provided between the sound absorption body 13 and each of inner walls of the side surfaces 11m, the front surface 11a and the upper surface 11c of the body 11.

Description

  The present invention relates to a sound insulation vent cap provided on an outer wall surface of a building in order to block noise entering the room from outside through a ventilation hole.

Conventionally, a soundproof hood (sound insulation vent cap) is attached to the ventilation hole in order to block noise entering the room from the ventilation hole (see, for example, Patent Documents 1 to 3).
FIGS. 10A and 10B are views showing an example of the sound insulation vent cap 50. The sound insulation vent cap 50 has a vent on the rear surface 53a which is a surface on the ventilation hole 22 side provided in the outer wall 21 of the building 20. FIG. 51 is formed, a box-shaped main body 53 in which an air inlet 52 for taking in outside air is formed in a lower surface 53 b facing the lower side of the building 20, a cylindrical connecting pipe 54 provided outside the air vent 51, and sound absorption. The material 55 is provided. The sound absorbing material 55 is made of a porous material such as urethane foam, and is pasted over the entire inner wall excluding the rear surface 53a and the lower surface 53b of the main body 53.
By adopting such a configuration, noise that enters the air inlet 52 from the outside is absorbed by the sound absorbing material 55 of the sound insulation vent cap 50, so that noise that enters the room 25 from the outside can be reduced.

JP 2008-164231 A JP 2006-171254 A JP 2007-3157 A

By the way, in order to sufficiently reduce noise from the outdoors, it is necessary to increase the thickness of the sound absorbing material 55. However, if the thickness of the sound absorbing material 55 is increased, the air passage becomes narrower, and therefore ventilation is insufficient. There is a problem of becoming.
On the other hand, if it is attempted to secure the air passage while increasing the thickness of the sound absorbing material 55, there arises a problem that the sound insulation vent cap 50 becomes large.
Moreover, in the sound insulation vent cap currently commercialized, the thickness of the sound absorbing material 55 used is about 30 mm. However, since the sound absorbing material 55 is expensive, it is sufficient to use a necessary minimum sound deadening material. Development of a sound insulation vent cap capable of obtaining a sound insulation effect is desired.

  The present invention has been made in view of conventional problems, and an object of the present invention is to provide a sound insulation vent cap that can effectively reduce noise from outside while ensuring a necessary air passage.

The present invention is a sound insulation vent cap that is attached to a ventilation hole provided on the outer wall surface of a building and blocks noise entering from outside, and is opposed to the rear surface, which is provided with an intake port for taking in outside air, and the rear surface A front surface that is connected to the front surface and the rear surface and includes a lower surface provided with a vent hole that communicates with the ventilation hole, an upper surface that faces the lower surface, and a side surface surrounded by the front surface, the rear surface, the upper surface, and the lower surface. A box-shaped main body and a sound absorber disposed outside a tubular virtual air passage connecting the air inlet and the air vent in the main body, and between the sound absorber and the side surface. Is characterized in that a gap is provided.
In this way, by providing a gap between the sound absorber and the inner wall of the main body, the noise from the outside attenuated through the sound absorber diffuses into the air layer of the gap and collides with the inner wall while interfering with each other. In addition, since the reflected sound is further attenuated by the sound absorber, it is possible to effectively reduce the noise that enters the room from the outdoors even if the sound absorber is thin. In addition, since the proportion of the volume of the sound absorber in the main body is small, not only the necessary air passage can be secured, but also the volume of the sound absorber to be used can be reduced, thereby reducing the manufacturing cost of the sound insulation vent cap. be able to.
In addition, the box-shaped main body of the present invention is not necessarily limited to a hexahedron in which each surface is a flat surface, and includes a case where surfaces other than the rear surface contacting the outer wall surface are formed as curved surfaces. For example, as shown in FIG. 1, even when the upper surface and the front surface are formed of a single smooth curved surface, the portion corresponding to the lower surface of the curved surface is regarded as the upper surface and the portion corresponding to the rear surface is regarded as the front surface. . 8A and 8B, the upper surface, the front surface, and the side surface of the main body 11 are curved surfaces formed by bending a single plate, and the portion corresponding to the lower surface of the curved surface. The portion corresponding to the upper surface and the rear surface is regarded as the front surface, and the portion surrounded by the front surface, the upper surface and the lower surface is regarded as the side surface.

The present invention is characterized in that a gap is also provided between the sound absorber and the front surface.
As described above, if a gap is provided not only between the sound absorber and the side surface but also between the front surface, the sound absorption effect of the reflected sound can be further enhanced.
The present invention is characterized in that the size of the gap changes from the lower surface side to the upper surface side.
Thus, if the thickness of the air layer between the sound absorber and the inner wall of the main body is changed, the reflected sound of the noise can be effectively attenuated, and the noise reduction effect is further improved. This noise reduction effect is realized particularly in the entire frequency band from the 500 Hz band to the 4000 Hz band.
In addition, as a method of changing the size of the gap between the sound absorber and the side surface and the gap between the sound absorber and the front surface, the shape of the sound absorber may be changed, or the shape of the side surface or the front surface May be changed.

Further, the present invention is characterized in that the sound absorber is formed by attaching a sound absorbing material to an attachment member having a through-hole or a mesh-like attachment member.
In this way, if the sound absorbing material is attached to the mounting member in advance, not only the sound insulation vent cap can be easily assembled, but also the sound absorbing material having a low hardness can be securely held at a predetermined position in the main body. be able to.

  The summary of the invention does not list all necessary features of the present invention, and sub-combinations of these feature groups can also be the invention.

It is a figure which shows the structure of the sound insulation vent cap which concerns on embodiment of this invention. It is a figure which shows the state which attached the sound-insulation vent cap to the outer wall of a building. It is a perspective view which shows the structure of the sound absorber which concerns on this Embodiment. It is a figure for demonstrating the sound insulation effect of the sound insulation vent cap of this invention. It is a figure which shows the other structure of the sound insulation vent cap by this invention. It is a figure which shows the other structure of the sound insulation vent cap by this invention. It is a figure which shows the other structure of the sound insulation vent cap by this invention. It is a figure which shows the other shape of the sound insulation vent cap to which this invention is applied. It is a graph which shows the result of having measured the sound transmission loss performance of the sound insulation vent cap of this invention. It is a figure which shows the structure of the conventional sound insulation vent cap.

  Hereinafter, the present invention will be described in detail through embodiments, but the following embodiments do not limit the invention according to the claims, and all combinations of features described in the embodiments are included. It is not necessarily essential for the solution of the invention.

1A to 1C are views showing the configuration of a sound insulation vent cap 10 according to an embodiment of the present invention, in which FIG. 1A is a longitudinal sectional view in an attached state, and FIG. The figure which looked at from the ventilation hole side, (c) figure is a perspective view. FIG. 2 is a view showing a state in which the sound insulation vent cap 10 is attached to the ventilation hole 22 opened in the outer wall 21 of the building 20.
The sound insulation vent cap 10 includes a main body 11, a connecting pipe 12, and a sound absorbing body 13.
The main body 11 is a hollow box-like member, and is provided on the outer wall 21 of the building with the surface 11a on the right side of FIG. The surface 11b on the ventilation hole 22 side is the rear surface, the upper surface 11c in FIG. 1A on the upper side of the building 20 is the upper surface, and the surface 11d facing the upper surface 11c is the lower surface. Each of the two surfaces surrounded by the front surface 11a, the rear surface 11b, the upper surface 11c, and the lower surface 11d is referred to as a side surface 11m.
An intake port 14 for taking in outside air is formed at the center of the lower surface 11d, and a ventilation port 15 communicating with the ventilation hole 22 is formed above the center of the rear surface 11b. Note that a mesh-shaped lid member for preventing foreign matter such as dead leaves from entering the main body 11 or a lid member formed with a slit is usually attached to the vent hole 15. This is omitted.
The connecting pipe 12 is a cylindrical member that protrudes from the peripheral edge of the vent hole 15 and has an outer diameter that is substantially equal to the inner diameter of the protective pipe 23 inserted into the inner wall of the ventilation hole 22. It is inserted into the ventilation hole 22.
In this example, the main body 11 and the connecting pipe 12 are made of SUS in consideration of corrosion resistance.

The sound absorbing body 13 includes a mounting member 13a and a sound absorbing material 13b, and is arranged so as to cover a tubular virtual air passage K connecting the air inlet 14 and the air vent 15 indicated by a one-dot chain line in FIG. The
FIG. 3 is a perspective view of the sound absorber 13 as viewed from the inlet 14 side.
As shown in the figure, the attachment member 13a is obtained by forming a plate material such as steel, aluminum, stainless steel or the like in which a large number of through holes are formed, such as punching metal, into a bowl shape.
The end surface 131 on the lower surface 11d side of the attachment member 13a is in contact with the lower surface 11d, and a straight line extending from the both ends of the semicircular portion 131a toward the rear surface 11b side along the edge portion on the front surface 11a side of the intake port 14. The end surface 132 on the rear surface 11b side is in contact with the rear surface 11b, and a semicircular portion 132a along the edge on the upper surface 11c side of the vent hole 15 and the lower surface 11d side from both ends of the semicircular portion 132a. The straight portion 131b of the end surface 131 and the straight portion 132b of the end surface 132 are connected by a common side 11L of the rear surface 11b and the lower surface 11d. That is, the mounting member 13a is straight one side and the end face 131 of the curved surface S _k with the curved surface S _k substantially along the imaginary air passage K connecting the semicircular portion 132a of the semi-circular portion 131a and the end face 132 of the end surface 131 It consists of two curved surfaces S _s surrounded by the portion 131 b and the straight portion 131 b of the end surface 132.
The sound absorbing material 13b is attached to the side of the attachment member 13a opposite to the virtual ventilation path K side.
In this example, a non-combustible nonwoven fabric having a thickness of about 7 mm was used as the sound absorbing material 13b.
As the attachment member 13a, a metal mesh such as a metal mesh knitted into the above-described shape may be used. As the sound absorbing material 13b, a porous material such as urethane foam or a fiber material such as glass wool or rock wool can be used in addition to the nonwoven fabric.
1B, the width W on the lower surface 11d side from the center of the vent 15 of the sound absorber 13 when viewed from the front surface 11a side or the rear surface 11b side is constant.

Next, the sound insulation effect of the sound insulation vent cap 10 will be described.
In the sound insulation vent cap 10 of the present invention, the sound absorbing material 13b is disposed outside the tubular air passage K connecting the air inlet 14 and the air vent 15, and each of the upper surface 11c, the front surface 11a, and the side surface 11m of the main body 11. Since air gaps are provided between the inner wall and the inner wall, as shown in FIGS. 1A and 1B, an air layer is formed between the sound absorbing material 13 b of the sound insulating vent cap 10 and the inner wall of the main body 11. 16 (16a, 16c, 16m) exists.
Of these air layers 16, the air layer that contributes most to the sound absorption effect is the air layer 16 m between the inner wall of the side surface 11 m and the sound absorber 13. By providing this air layer 16 m, The noise toward the inner wall can be attenuated, and the reflected sound from the inner wall of the side surface 11m can be attenuated. In this example, by increasing the thickness of the air layer 16m between the inner wall of the side surface 11m that contributes most to the sound absorption effect and the sound absorber 13, noise from the outdoors is effectively attenuated.
If an air layer 16a is also provided between the sound absorber 13 and the front surface 11a, noise from the inlet 14 toward the inner wall of the front surface 11a can be attenuated, and reflected sound from the inner wall of the front surface 11a is also attenuated. Therefore, the sound absorption effect can be further enhanced. Even if the air layer 16a between the inner wall of the front surface 11a and the sound absorber 13 is thin, most of the reflected sound from the inner wall of the front surface 11a is a portion on the upper surface 11c side and a side surface 11m side of the sound absorber 13. Therefore, there is no problem even if the air layer 16a is thinned.
Further, in the air layer 16c between the inner wall of the upper surface 11c and the sound absorber 13, most of the reflected sound from the inner wall on the front surface 11a and the side surface 11m side is already attenuated by the portion on the side surface 11m side of the sound absorbing material 13b. Therefore, there is no problem even if the air layer 16c is thinned.

As shown in FIG. 2, the noise from the outdoor noise source 30 is reflected by the veranda 24, the outer wall 21, etc., and enters the inlet 14 of the shielding vent cap 10 from various directions. That is, the noise intrusion direction is random unlike the intake air direction. Noise that has entered from the air inlet 14 enters the room 25 from the air vent 15 through the ventilation hole 22 while being reflected on the inner wall of the main body 11.
In the conventional sound insulation vent cap 50 shown in FIG. 10 in which the sound absorbing material 55 is attached to the inner wall of the main body 53, when the thickness of the sound absorbing material 55 is as thin as 7 mm as in this example, the sound absorbing material 55 Since the sound absorption effect is reduced, it is difficult to sufficiently attenuate the noise.
On the other hand, as shown in FIG. 4, the sound insulation vent cap 10 of this example is provided with an air layer 16m between the inner wall of the side surface 11m of the main body 11 and the sound absorbing body 13, and therefore the side surface of the sound absorbing material 13b. The sound A entering from the outside attenuated through the surface on the 11m side passes through the air layer 16m and is reflected by the inner wall of the side surface 11m, and then again passes through the surface on the side surface 11m side of the sound absorbing material 13b. Accordingly, not only the sound A entering from the outdoors is attenuated but also the reflected sound of the sound A is attenuated, so that the noise from the outdoors can be effectively reduced.

  Thus, in the present embodiment, the sound absorber 13 provided inside the main body 11 of the sound insulation vent cap 10 is made of the attachment member 13a made of a plate material having a large number of through holes and the nonwoven fabric attached to the attachment member 13a. The sound absorber 13 is arranged outside the tubular virtual air passage K that connects the air vent 15 and the air inlet 14, and the sound absorber 13 and the upper surface 11 c and the side surface 11 m of the main body 11. Since the air layer 16 is provided between each of the inner walls, the sound reflected from the inner wall can be attenuated by the sound absorbing material 13b. Therefore, even if the thickness of the sound absorbing material 13b is reduced, noise from the outside can be effectively reduced and the manufacturing cost can be reduced.

In the embodiment described above, the case where the thickness of the air layer 16m between the inner wall of the side surface 11m and the sound absorber 13 is constant has been described, but as shown in FIGS. 5 (a) and 5 (b), If the width W of the sound absorber 13 is increased toward the lower surface 11d side, the thickness of the air layer 16 can be changed between the inner wall of the side surface 11m and the sound absorber 13 toward the lower surface 11d side.
As described above, when the thickness of the air layer 16 is changed, the sound B and the sound C that have entered from different places of the sound absorber 13 are reflected from the inner wall of the side surface 11m and returned to the sound absorber 13. Since the propagation distances of the reflected sound come different, the interference between the reflected sounds increases, and the reflected sound can be further attenuated. Therefore, noise in a wide frequency band (500 Hz band to 4000 Hz band) can be effectively attenuated.
Note that the change in the thickness of the air layer 16 is not necessarily changed linearly, and may be changed by curving the surface of the sound absorber 13 on the side surface 11m side.
Further, as a method of changing the thickness of the air layer 16, as shown in FIG. 6, the sound absorber 13 is made constant in the width W of the sound absorber 13 as in the above embodiment, and the side surface 11m is replaced with the upper surface 11c. And it may be inclined with respect to the lower surface 11d.

In the above example, the sound insulation vent cap 10 having the main body 11 in which the upper surface 11c and the front surface 11a are continuous and the front surface 11a side of the upper surface 11c and the upper surface 11c side of the front surface 11a are curved has been described. The present invention is also applicable to a sound insulation vent cap 10Z having a shape of the main body 11 different from that of FIG. 1, for example, as shown in FIG. In this case, the sound absorber 13 according to the embodiment may be used as the sound absorber, and the shape of the end surface 131 on the lower surface 11d side as shown in FIG. The sound absorber 13Z may be used.
In addition, as shown in FIGS. 8A and 8B, the present invention provides a sound insulation vent cap 10Z in which the upper surface, the front surface, and the side surface of the main body 11 are curved surfaces formed by bending a single plate material. Is also applicable. Specifically, the surface on which the vent hole 15 is provided is the rear surface 11b, and the surface on which the air inlet port 14 is provided is the lower surface 11d, and a portion facing the lower surface 11d of the curved surface indicated by 11c in FIG. (B) is a front surface, a portion (substantially vertical portion) facing the rear surface 11b of the curved surface shown by 11a in FIG. 11 is a front surface, a front surface 11a (rear surface 11b) shown by 11m in FIG. The sound body 13R is disposed outside the tubular virtual air passage K that connects the air vent 15 and the air inlet 14, and the sound absorber 13R and the front surface 11a of the main body 11 are disposed. If it arrange | positions so that an air layer may be provided between each inner wall of the upper surface 11c and the side surface 11m, the reflected sound from an inner wall can also be attenuate | damped reliably.
In the above example, the sound absorber 13 is formed by attaching the sound absorbing material 13b made of non-woven fabric to the mounting member 13a made of punching metal. However, the sound absorbing body 13 may be composed only of the sound absorbing material 13b. In this case, as the sound absorbing material 13b, a non-woven fabric having a high density and therefore a high hardness can be used.
[Experimental example]

The sound insulation vent cap according to the present invention shown in FIG. 1 and FIG. 5 (the present invention 1 and 2), the vent cap without the sound absorbing material (comparative example), and the sound insulating vent cap attached to the inner wall of the main body (reference) Example) and the results of measuring the sound transmission loss of these vent caps are shown in FIG. However, the thicknesses of the sound absorbing materials of the present inventions 1 and 2 and the reference example were all 7 mm.
The sound transmission loss test was measured according to the measurement methods of JIS A 1416 and JIS A 1428.
The horizontal axis of the graph is the octave band center frequency (Hz), and the vertical axis is the normalized sound transmission loss (dB). The sound transmission loss is the difference (dB) between the sound energy incident on the test body and the sound energy passing through the test body. The normalized sound transmission loss (dB) is the sound transmission to eliminate the difference in test results due to the opening area. The loss is a value obtained by standardizing the test area to 1 m ² .
As is clear from FIG. 9, the sound insulation vent caps of the present invention 1 and 2 in which an air layer is provided between the inner wall of the side surface and the sound absorbing body provides a high sound insulation effect in all frequency bands from the 500 Hz band to the 4000 Hz band. It was confirmed that Further, as apparent from a comparison between the present invention 1 and the present invention 2, when the thickness of the air layer between the inner wall of the side surface and the sound absorber is changed, the sound insulation effect is further enhanced.
On the other hand, it was also confirmed that even when the sound absorbing material was affixed to the inner wall of the main body as in the reference example, if the sound absorbing material was as thin as the present invention, a sufficient sound insulation effect could not be obtained.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the embodiment. It is apparent from the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  As described above, since the sound insulation vent cap of the present invention can effectively reduce noise from the outside using a small amount of sound absorbing material, it is particularly used as a sound insulation vent cap attached to the outer wall of an apartment or the like. be able to.

10 sound insulation vent cap, 11 body, 11a front surface, 11b rear surface,
11c upper surface, 11d lower surface, 11m side surface, 12 connecting pipe, 13 sound absorber,
13a mounting member, 13b sound absorbing material, 14 air inlet, 15 air vent,
16a, 16c, 16m Air layer, 20 building, 21 outer wall, 22 ventilation hole,
23 protection tubes, 24 verandas, 25 indoors, 30 noise sources.

Claims (4)

A sound insulation vent cap that is attached to a ventilation hole provided on the outer wall surface of the building and blocks noise entering from outside,
A rear surface provided with an intake port for taking in outside air, a front surface facing the rear surface, a lower surface having a vent hole communicating with the ventilation hole and connected to the front surface and the rear surface, and opposed to the lower surface A box-shaped body having an upper surface and a side surface surrounded by a front surface, a rear surface, an upper surface and a lower surface;
A sound absorber disposed outside a tubular virtual air passage connecting the air inlet and the air vent in the main body,
A sound insulation vent cap, wherein a gap is provided between the sound absorber and the side surface.   The sound insulation vent cap according to claim 1, wherein a gap is provided between the sound absorbing body and the front surface.   The sound insulation vent cap according to claim 1 or 2, wherein the size of the sound absorber and the gap changes from the lower surface side to the upper surface side.   The sound absorbing body according to any one of claims 1 to 3, wherein the sound absorbing body is formed by attaching a sound absorbing material to an attachment member having a through hole or a mesh-like attachment member. Vent cap.

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