JP7188908B2 - sound absorbing structure - Google Patents

Description

The present invention relates to sound absorbing structures. More specifically, one unit sound absorber is installed through an opening in at least one of the ceiling surface, wall surface or floor surface facing the space, and a structure installed in the space (hereinafter referred to as "ceiling surface etc."). It relates to one or more adjacent sound absorbing structures.

When a linear opening, such as a short slit as shown in Non-Patent Document 1, is provided, in order to improve the sound absorption performance over a wider range of frequency characteristics than the frequency characteristics determined by the width of the slit, the hole opening provided with the slit It is common to place a porous sound absorbing material behind the plate.

On the other hand, in the technique described in Patent Document 1, in a sound absorbing structure using a Helmholtz resonator, a very narrow gap is provided as an opening of the resonator. Since no sound-absorbing material is provided, the sound absorption coefficient is high only in a narrow frequency band, and depending on the frequency component of the sound, the sound absorption coefficient may be low.

JP 2015-102729 A

Edited by Japan Acoustic Materials Association "Sound Absorbing Materials" Published by Gihodo Publishing Co., Ltd. pp67-68

In view of such conventional circumstances, it is an object of the present invention to provide a sound absorbing structure having a structure different from that described above and capable of obtaining a high sound absorption coefficient in a wide frequency range.

In order to achieve the above object, the sound absorbing structure according to the present invention is characterized in that one or more unit sound absorbers are adjacent to each other through openings in the ceiling surface or the like, and communicate with the openings. It comprises a vertical cavity and a horizontal cavity extending laterally of the vertical cavity, wherein a flow resistance material is provided at a boundary between each of the horizontal cavities and the vertical cavity, and the horizontal cavity is a space located on the side of the space. It is formed by being surrounded by the side member, the mounting side member positioned on the mounting side to the ceiling surface or the like, and the rib connecting the two side members. According to experiments by the inventors using the same configuration, a high sound absorption coefficient was obtained in a wide frequency range with a structure different from the above-described conventional structure.

Further, by providing an end projecting portion toward the mounting side member in the vicinity of the opening of the space side member, the flow resistance member does not come off and cannot be seen from the outside, thereby improving the design. Further, by providing a middle protruding portion on the facing surface of at least one of the space side member and the mounting side member to prevent the flow resistance member from intruding deeper, the position of the flow resistance member is stabilized.

According to experiments by the inventors, it is desirable that the bulk density of the flow resistance material is 25 to 150 kg/m ³ . A pair of the horizontal cavities may be provided in the unit sound absorber, and the vertical cavity may be located between the pair of horizontal cavities and have the mounting side member as a bottom.

During construction, each horizontal cavity of a pair of adjacent unit sound absorbers is assembled into the same unit member by the rib, the spatial side member, and the mounting side member, and a plurality of these unit members are arranged and the above-mentioned A vertical cavity is preferably formed. In this case, the unit sound absorbers can be continued at a constant pitch.

On the other hand, the horizontal cavity and the vertical cavity in one unit sound absorber may be continuously incorporated into the same single member by the mounting side member, and a plurality of such unit members may be arranged side by side. According to this configuration, the unit sound absorbers can be arranged at variable pitches. In this case, it is preferable to attach a ceiling material between the space side members on the side of the opening between adjacent single sound absorbers. More specifically, the opening is linear, and a mounting portion provided along the longitudinal direction of the linear opening in the intermediate portion of the mounting side member and a field at an arbitrary position in the longitudinal direction of the groove-shaped opening are provided. It is preferable that the edge support is provided with a mounting tool to which the mounting portion can be attached, and that the mounting tool can be attached at any position in the longitudinal direction of the ceiling joist support.

Also, some unit sound absorbers may not be provided with the flow resistance material. That is, by omitting one or both of the flow resistance materials in some unit sound absorbers, it is possible to reduce the sound absorption effect in those parts and adjust the reflection in the space.

According to the characteristics of the sound absorbing structure according to the present invention, it is possible to obtain a high sound absorption coefficient in a wide frequency range with a structure different from that of the conventional structure.
Other objects, configurations and effects of the present invention will become apparent from the following detailed description of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a sound absorbing structure according to the present invention, wherein (a) is a vertical cross-sectional view of a unit member, and (b) is a vertical cross-sectional view of a ceiling structure formed by arranging a plurality of unit members of (a). (a) is a sectional view taken along the line AA of FIG. 1, and (b) is a bottom view of the ceiling surface. It is a partial expanded sectional view of FIG.1(b). (a) is a view corresponding to FIG. 3 showing a second embodiment of the present invention, and (b) is a view corresponding to FIG. 3 showing a third embodiment of the present invention. 4 shows a fourth embodiment of the present invention, (a) is a longitudinal sectional view showing an attached state, (b) is an enlarged sectional view of (a), and (c) is a sectional view taken along the line BB of (b). be. It is a figure equivalent to Fig.5 (a) which shows 5th embodiment of this invention. (a) is a vertical cross-sectional view showing a sound absorbing structure for confirming the effect of the flow resistance material by experiment, and (b) is a partial exploded view of (a). FIG. 3 is a vertical cross-sectional view showing a sound absorbing structure of a comparative example used in an experiment; It is a graph of experimental results showing the effects of the present invention.

Next, the sound absorbing structure according to the present invention will be described in more detail with reference to the accompanying drawings as appropriate. In the following embodiments, a sound absorbing structure that is housed through an opening in a ceiling surface facing a space will be described.

First, the basic configuration of the present invention will be described with reference to FIGS. 1 to 3. FIG. In addition, each member may be formed of aluminum embossed material or the like that is continuous in the direction perpendicular to the paper surface, or may be formed by bending a steel plate, molding a flame-retardant material, or the like. The sound absorbing structure 1 is constructed by arranging a plurality of unit members 7, and the unit members 7 are constituted by a frame 10, a mounting portion 20, an insertion portion 22, and a flow resistance material 3 such as glass wool installed inside the frame 10. be. Each member constituting the sound absorbing structure 1 is continuous in the direction perpendicular to the paper surface of FIGS. 1 and 3 .

The frame 10 includes a space side member 11 facing the space 100, a mounting side member 12 positioned on the base structure side of the ceiling, which is the mounting side, and a rib 13 connecting them. In order to fix the flow resistance member 3 to the frame 10, the space side member 11 has a first end protrusion 11a and a first intermediate protrusion 11b, and the mounting side member 12 has a second end protrusion 12a and a second end protrusion 12a. A middle protruding portion 12b is provided respectively.

Since the lower surface of the space side member 11 faces the space 100, it is decorated. By providing the first end projecting portion 11a, the flow resistance material 3 is not visible even when looking up from the space 100 side, and is configured to be held.

A ceiling joist 40 to which the unit member 7 is attached is fixed to a joist holder 41 with a joist clip 42, and each joist holder 41 is supported by a hanging bolt 44 by a hanger 43 to form a ceiling structure. The unit members 7 are fixed to the joists 40 by the screws 30 through the mounting portions 20, and the insertion portions 22 are inserted into the concave portions 21 of the adjacent unit members to form the sound absorbing structure 1 in which the unit sound absorbers 2 are continuously arranged. be.

That is, the space between the ribs 13, 13 between the pair of adjacent unit members 7, 7 becomes one unit sound absorber 2, and the opening 102 between the spatial side members 11, 11 becomes the entrance of the Helmholtz resonator. A vertical cavity 4 communicating with the opening 102 and a pair of horizontal cavities 5, 5 extending on both sides of the vertical cavity are provided. The structure is such that the flow resistance members 3, 3 are provided facing each other at the boundary of the cavity 5). The inner opening 6 is formed between the first end projection 11a and the second end projection 12a, which are the boundaries between the vertical cavity 4 and the horizontal cavity 5, and is wider than the previous opening 102, whereby the opening 102 becomes the Helmholtz resonator. serves as an entrance to The same applies to the following other embodiments.
Another embodiment of the present invention is described below. The same reference numerals are attached to the same members as in the above embodiment.

The second embodiment shown in FIG. 4(a) shows an example of installation on a slanted ceiling in which the joists 40 are arranged slantingly. The ribs 13 are vertical, but the space side members 11 and the mounting side members 12 are inclined along the ceiling surface. In the third embodiment shown in FIG. 4(b), the unit sound absorber 2 is provided with only one flow resistance material 3, one vertical cavity 4, and one horizontal cavity 5. As shown in FIG. The longitudinal cavity 4 is formed between the ribs 13 and the lateral cavities 5 of the adjacent unit members 7,7.

In the fourth embodiment shown in FIG. 5, unit sound absorbers 2 are housed in one frame 10 and are provided on the ceiling with a plurality of unit sound absorbers 2, 2 separated from each other. A unit in which a unit sound absorber 2 having one vertical cavity 4, a pair of horizontal cavities 5, 5 and a pair of flow resistance members 3, 3 is housed in one frame 10 is attached to a ceiling joist support 41. A ceiling plate 46 is fixed to the space side member 11 to form a ceiling surface 101 having an opening 102 between the unit sound absorbers 2 , 2 .

A mounting portion 14 having a groove 14a provided with a pair of upper flanges is provided along the longitudinal direction in the upper central part of each frame 10, and the head of a bolt 32 of a mounting tool 31 is locked in the groove 14a. slidable in the longitudinal direction. An engaging portion 24 having a U-shaped cross section of the mounting member 23 is engaged at an arbitrary position of the joist support 41 and fixed with a screw 30 . Then, the bolts 32 are passed through the through holes of the pair of flanges 25, 25 projecting sideways from the lower end of the locking portion 24 and the washer 34, and are fastened with nuts 33, and fixed at an arbitrary position of the joist support 41. do. According to this structure, joists are not required, and the unit sound absorbers 2 can be appropriately arranged, thereby improving the degree of freedom in design.

Experimental examples of the present invention are shown below. FIG. 7 shows the sound absorbing structure 1 used in the experiment, in which the openings 102 of the unit sound absorbers 2 are continuous within 3.6 m in the vertical direction, and 21 unit sound absorbers 2 are housed in the 3.675 m horizontal region. ing. 1B is an exploded view of FIG. 1A, in which a pair of channel members 203, 203 with lips are arranged back-to-back on a continuous mounting-side member 202, and the space-side member 201 is covered, and a pair of angle A material 204 is fixed.

During the experiment, two or one (only FR4) of the above-described flow resistance materials 3 were arranged in the portions indicated by FR1 to FR4. The flow resistance materials used in the experiment had a bulk specific gravity (unit: kg/m ³ ) of 96 for FR1, 32 for FR2, 96 for FR3, and 96 for FR4, all of which had a thickness of 25 mm.

FIG. 8 is a comparative example in the experiment. This sound absorbing structure 501 is shown in Patent Document 1 above, and passes through a unit sound absorber 502 and a sound introducing portion 511. An opening ( gap) 512 and cavity 513.

FIG. 9 is a graph showing experimental results. Regarding FR1, which is the result of the implementation of the present invention, there is a clear difference compared to no FR and the comparative example shown in FIG. It was found that even when compared with FR4 provided with a resistance material, a high sound absorption coefficient can be obtained in a wide frequency range. As for FR2, which was performed for reference, the overall performance is lowered by lowering the bulk specific gravity of the glass wool, so it is presumed that FR4 will have the same tendency. Moreover, the superiority of the configuration of the present invention can be seen from the fact that FR2 is superior to FR4, which has a high bulk density, in the audible range of 400-630 Hz, which is important for human speech. The bulk specific gravity of the flow resistance material may be appropriately changed according to the site, but according to the inventors' experiments, the bulk specific gravity of the flow resistance material is 25 kg/m ³ to 150 kg/m ³ and is practical. It was confirmed.

Further embodiments of the present invention are enumerated. In addition, each of the above embodiments and the following embodiments can be implemented in combination with each other. For example, the third embodiment shown in FIG. 4(b) may be applied to the fourth embodiment shown in FIG. In this case, as shown in FIG. 6, in the unit member 7 (unit sound absorber 2), only one flow resistance material 3, one vertical cavity 4, and one horizontal cavity 5 are provided. It may be surrounded by ribs provided. The ceiling plate 46 is preferably provided between the space side member 11 and the flange 13a.

The arrangement, materials, and dimensional ratios of the opening 102, the inner opening 6, the vertical cavity 4, the horizontal cavity 5, and the flow resistance material 3 can be changed as appropriate, and may be determined according to the required sound absorption performance. The flow resistance material 3 may be made of any porous material other than glass wool, such as polyester wool, rock wool, aluminum fiber sound absorbing material, and the like.

By omitting one or both of the flow resistance materials 3 in some of the unit sound absorbers 2, it is possible to reduce the sound absorbing effect in that portion and adjust the reflection in the space. Therefore, it is possible to selectively use the sound-absorbing surface and the sound-reflecting surface of the finishing material of the same design that constitutes the present sound absorbing structure 1 .

In the above embodiment, the ceiling surface was exemplified, but the implementation may be performed on at least one of a wall surface, a floor surface, and a structure installed in a space.

In the above embodiment, in order to fix the flow resistance member 3 to the frame 10, the space side member 11 has the first end protrusion 11a and the first middle protrusion 11b, and the attachment side member 12 has the second end protrusion 12a. , and the second middle projecting portion 12b. However, if the flow resistance material 3 is stabilized, the first middle projecting portion 11b may be omitted, or either one of the second end projecting portion 12a and the second middle projecting portion 12b may be omitted.

In the above-described embodiment, the opening 102 is a linear opening that continues in the direction perpendicular to the paper surface of FIGS. However, the present invention may be practiced with respect to openings intermittently provided without being continuous in the direction perpendicular to the plane of FIGS. Moreover, it is also possible to implement it in the ceiling etc. which the opening 102 was provided as a curved opening in bottom view.

In the above embodiment, the sound absorbing structure 1 is incorporated in the ceiling surface or the like, but these sound absorbing structures 1 may be used alone. For example, it is also possible to install the unit sound absorber 2 shown in FIGS. In this case, the flange 13a and the mounting portion may not be provided.

The sound absorbing structure according to the present invention is effective, for example, in reducing the sound pressure level in a space such as a subway where a lot of noise is generated. It has the effect of reducing noise in places where many people gather, such as station concourses and shops, and making guidance announcements and emergency guidance announcements clearer.

1: sound absorbing structure, 2: unit sound absorber, 3: flow resistance material, 4: vertical cavity, 5: horizontal cavity, 6: inner opening, 7: unit member, 10: frame, 11: space side member, 11a: First end projecting portion 11b: First middle projecting portion 12: Mounting side member 12a: Second end projecting portion 12b: Second middle projecting portion 13: Rib 13a: Flange 14: Mounting portion 14a : groove, 20: mounting portion, 21: recessed portion, 22: insertion portion, 23: mounting member, 24: locking portion, 25: flange, 30: screw, 31: mounting fixture, 32: bolt, 33: nut, 34: washer, 40: joist, 41: joist receiver, 42: joist clip, 43: hanger, 44: hanging bolt, 46: ceiling plate, 100: space, 101: ceiling surface, 102: opening, 201: Space side member 202: Mounting side member 203: Lipped channel member 204: Angle member 501: Sound absorbing structure 502: Unit sound absorber 511: Sound introduction portion 512: Opening (gap) 513: cavity

Claims (10)

One or more unit sound absorbers adjoin through an opening in at least one of the ceiling surface, wall surface or floor surface facing the space, and structures installed in the space (hereinafter referred to as "ceiling surface, etc."). A sound absorbing structure that
comprising a vertical cavity communicating with the opening and a horizontal cavity extending laterally of the vertical cavity, and a flow resistance material provided at the boundary between each horizontal cavity and the vertical cavity;
The sound-absorbing structure, wherein the horizontal cavity is formed by being surrounded by a space side member located on the space side, a mounting side member located on the attachment side to the ceiling surface or the like, and ribs connecting these two side members. 2. A sound absorbing structure according to claim 1, wherein an end protruding portion is provided toward said mounting side member in the vicinity of said opening of said space side member. 3. A sound absorbing structure according to claim 1 or 2, wherein at least one of said space side member and said mounting side member has a middle protruding portion provided on the facing surface thereof for preventing said flow resistance member from intruding into the depth. The sound absorbing structure according to any one of claims 1 to 3, wherein the flow resistance material has a bulk density of 25 to 150 kg/m ³ . The sound absorber according to any one of claims 1 to 4, wherein a pair of said horizontal cavities are provided in said unit sound absorber, and said vertical cavity is located between said pair of horizontal cavities and has said mounting side member as a bottom. Structure. Each horizontal cavity of a pair of adjacent unit sound absorbers is assembled into the same unit member by the rib, the spatial side member, and the mounting side member, and a plurality of the unit members are arranged to form the vertical cavity between the unit members. 6. A sound absorbing structure according to claim 5. The sound absorber according to any one of claims 1 to 5, wherein the horizontal cavity and the vertical cavity in one unit sound absorber are continuously incorporated into the same single member by the mounting side member, and a plurality of such unit members are arranged side by side. Structure. 8. A sound absorbing structure according to claim 7, wherein a ceiling material is attached between said space side members on the sides of said opening between adjacent single sound absorbers. The opening is linear, and a mounting portion provided along the longitudinal direction of the linear opening in the middle portion of the mounting side member, and the mounting portion on the ceiling joist receiver at an arbitrary position in the longitudinal direction of the groove. 9. The sound absorbing structure according to claim 7 or 8, further comprising a mounting fixture capable of mounting said ceiling joist holder at any position in the longitudinal direction of said ceiling joist holder. The sound absorbing structure according to any one of claims 1 to 9, wherein the flow resistance material is not provided in some unit sound absorbers.

Images