Sound insulation system and partition facility

Abstract

To provide a sound insulation system that provides high sound insulation performance without completely closing a space.SOLUTION: A partition facility 100 comprising a sound insulation system is installed in an object space encircled with a wall member 110W and a floor member 110F as partition members, and having an opening part, and comprises acoustic members 60 and a sound insulation structure 50. The acoustic members 60 are fitted to an inner surface of the partition member, and exert an acoustic action, which is different from the inner surface of the partition members, on an incident sound to the acoustic members 60. The sound insulation structure 50 is fitted at a position closer to the opening part than the acoustic members 60, and sound waves SW1 to SW5 propagated from a sound source SS in the object space to the outside are reduced.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a sound insulation system and partitioning equipment.

Background Art

[0002] In recent years, with the spread of video conferencing, booth-type equipment is being installed everywhere. Booth-type equipment can be roughly classified into a closed type, a semi-closed type, and an open type according to the degree of its openness. Open-type or semi-closed type booths are excellent in terms of ease of installation, but since at least a part of the ceiling or side surface is open, the sound in the internal space easily leaks outside, and conversely, outside sound easily enters the internal space, so there are difficulties in terms of quietness. On the other hand, in a closed-type booth, since the ceiling and all side surfaces are blocked, leakage of the sound in the internal space can be suppressed. Further, Patent Document 1 discloses a technical idea of configuring a sound-absorbing ceiling using a sound-absorbing cloth and a sound-absorbing material. If the technology of Patent Document 1 is applied to booth-type equipment, there is a possibility of improving the quietness inside the booth.

[0003] On the other hand, closed-type booths have a problem of being inferior in terms of ease of installation due to restrictions on the installation environment and high costs. For example, since the ceiling of a closed-type booth is blocked, even if a sprinkler is installed on the ceiling of the building where the booth is installed, the water of the sprinkler does not reach inside the booth. Therefore, individual fire prevention measures such as installation of a sprinkler inside the booth equipment are required.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Not limited to examples of such booth-type facilities, while it is required to improve sound insulation between the inside and outside of a specific space, it may be required to allow fluids such as water or air and other small objects to pass between the inside and outside of that space.

[0006] An object of the present disclosure is to achieve high sound insulation performance without completely closing the space.

Means for Solving the Problems

[0007] A sound insulation system according to an aspect of the present disclosure is a sound insulation system installed in a target space surrounded by a partition member and having an opening, the sound insulation system including an acoustic member attached to the inner surface of the partition member, the acoustic member being an acoustic member that exerts an acoustic action different from that of the inner surface of the partition member on incident sound to the acoustic member, and a sound insulation structure attached at a position closer to the opening than the acoustic member and reducing sound propagating from the inside to the outside of the target space.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0009] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings for explaining the embodiment, the same components are generally denoted by the same reference numerals, and repeated explanations thereof are omitted.

[0010] In the following description, when a common description is given for a plurality of like elements, a common reference numeral such as "99" may be used. On the other hand, when individual descriptions are given for these elements, reference numerals with subscripts added to the common reference numeral such as "99-1" or "99-2" may be used.

[0011] (1) Configuration of Sound Insulation Unit The configuration of the sound insulation unit of this embodiment will be described. FIG. 1 is a perspective view of the sound insulation unit of this embodiment. FIG. 2 is a view of the sound insulation unit of this embodiment as seen from the X-direction. FIG. 3 is a graph illustrating the frequency characteristics of the transmission loss of the sound insulation unit of this embodiment.

[0012] As shown in FIG. 1, the sound insulation unit 10 includes a resonator 11, a resonator 12, and a resonator 13. In the following description, the X+ direction, X− direction, Y+ direction, Y− direction, Z+ direction, and Z− direction are defined with respect to the sound insulation unit 10. By determining the orientation of the sound insulation unit 10 such that the Z+ direction is along the sound propagation direction, the sound insulation unit 10 can effectively block (reduce) the sound.

[0013] The resonators 11, 12, and 13 are all continua extending in the X-axis direction. In the example of FIG. 1, the resonators 11, 12, and 13 have a shape in which an end portion in the -Z direction is cut out from a side surface of a hollow cylinder extending in the X-axis direction so that the internal space and the external space can communicate with each other. The resonators 11, 12, and 13 all have a tube structure in which the dimension in the X-axis direction is longer than half of the wavelength corresponding to the sound insulation target frequency. The resonators 11, 12, and 13 have a C-shaped cross-sectional shape in any plane orthogonal to the X-axis and function as Helmholtz resonators. The resonators 11, 12, and 13 transmit a secondary wave having a phase opposite to that of the incident wave. The primary wave of sound directly transmitted through the gap of the resonator is attenuated by interfering with the secondary wave generated and transmitted by resonance.

[0014] As shown in FIG. 2, the resonator 12 is provided at a position spaced apart by a distance Tz in the Z+ direction from the resonator 11. The resonator 13 is provided at a position spaced apart by a distance Tz in the Z+ direction from the resonator 12. That is, the resonators 11, 12, and 13 constituting the sound insulation unit 10 are arranged at a substantially equal interval Tz along the Z-axis. In the present embodiment, the distance between two resonators in the Z+ direction represents the distance in the Z+ direction between the centroid positions in the YZ cross-sections of the two resonators. Note that the sound insulation unit 10 of the present embodiment is not limited to three, and four or more resonators may be arranged at a period of the interval Tz along the Z-axis. Thereby, similar to a phononic crystal, the sound insulation unit 10 maximizes the transmission loss at the frequency fTz corresponding to the wavelength λTz depending on the interval Tz. That is, the sound insulation unit 10 exhibits high sound insulation performance at the frequency fTz. Here, the wavelength λTz is proportional to the interval Tz.

[0015] In the example of FIG. 2, a gap is provided between a plurality of resonators adjacent in the Z+ direction. Thereby, fluid (e.g., air or water), light, or other objects can flow through the gap between adjacent resonators. However, a plurality of resonators adjacent in the Z+ direction may be connected. According to this configuration, since a plurality of resonators can be manufactured integrally, the manufacturing of the sound insulation unit 10 becomes easy. In order to enhance the light transmissibility of the sound insulation unit 10, the resonator 11, the resonator 12, and the resonator 13 may be made of a material having light transmissibility (e.g., a transparent or translucent resin material such as glass or acrylic). However, since the sound insulation unit 10 exhibits sound insulation performance due to its structure, there is a high degree of freedom in the selection of the material, and it can be composed of various materials such as resin, metal, silicon, rubber, polymer, paper, cardboard, wood, or non-woven fabric. Therefore, it is possible to impart sound insulation performance to an existing housing or to configure it as an environmentally considerate member by utilizing thinned wood or recycled materials.

[0016] The resonator 11 is configured to resonate at a frequency f1. The resonance frequency f1 depends on the radial thickness (i.e., the difference between the outer radius and the inner radius) l1 of the resonator 11, the circumferential width w1 of the notch (slit) of the resonator 11, and the internal cross-sectional area S1 of the hollow cylinder. Specifically, the resonance frequency f1 is proportional to the square root of the value obtained by dividing the slit width w1 by the product of the thickness l1 and the internal cross-sectional area S1.

[0017] The resonator 12 is configured to resonate at a frequency f2. The resonance frequency f2 depends on the radial thickness l2 of the resonator 12, the circumferential width w2 of the notch of the resonator 12, and the internal cross-sectional area S2 of the hollow cylinder. Specifically, the resonance frequency f2 is proportional to the square root of the value obtained by dividing the slit width w2 by the product of the thickness l2 and the internal cross-sectional area S2.

[0018] The resonator 13 is configured to resonate at a frequency f3. The resonance frequency f3 depends on the radial thickness l3 of the resonator 13, the circumferential width w3 of the notch of the resonator 13, and the internal cross-sectional area S3 of the hollow cylinder. Specifically, the resonance frequency f3 is proportional to the square root of the value obtained by dividing the slit width w3 by the product of the thickness l3 and the internal cross-sectional area S3.

[0019] In this embodiment, the parameters of the resonator 11, the resonator 12, and the resonator 13 (that is, the slit width, the thickness, and the internal cross-sectional area) are designed so that the resonance frequency f1, the resonance frequency f2, and the resonance frequency f3 are different from each other. Further, in this embodiment, the resonators 11, 12, and 13 are arranged so that the frequency fTz depending on the interval Tz is different from any of the resonance frequencies f1, f2, and f3. As a result, as shown in FIG. 3, the transmission loss of the sound insulation unit 10 is maximized at the resonance frequencies f1, f2, and f3 and the frequency fTz depending on the interval Tz (that is, it has four peaks). Therefore, the sound insulation unit 10 can exhibit high sound insulation performance over a wide frequency band.

[0020] Furthermore, as shown in FIG. 3, the interval Tz may be determined so that the frequency fTz depending on the interval Tz is higher than any of the resonance frequency f1, the resonance frequency f2, and the resonance frequency f3 (in other words, the resonators 11, 12, and 13 may be arranged). Thereby, since the interval Tz can be shortened, the dimension of the sound insulation unit 10 in the Z-axis direction can be made compact.

[0021] (2) Configuration of the sound insulation structure The configuration of the sound insulation structure of this embodiment will be described. FIG. 4 is a perspective view of the sound insulation structure of this embodiment.

[0022] As shown in Fig. 4, the sound insulation structure 50 is configured by arranging five sound insulation units 10-1 to 10-5 in the Y-axis direction. Note that the sound insulation structure of this embodiment may include two to four sound insulation units 10, or six or more sound insulation units 10. Further, the sound insulation structure of this embodiment can be constructed not only in the Y-axis direction but also by arranging the sound insulation units 10 in an arbitrary direction orthogonal to the Z-axis.

[0023] Note that a gap is provided between a plurality of adjacent sound insulation units 10 in the Y+ direction. Thereby, fluid (for example, air or water), light, or other objects can flow through the gap between the adjacent sound insulation units 10. In order to enhance the light transmittance of the sound insulation structure 50, the resonators 11, 12, and 13 included in each sound insulation unit 10 may be made of a material having light transmittance.

[0024] The interval between adjacent sound insulation units 10 in the Y+ direction can be arbitrarily determined. The smaller the interval, the more the sound passing through the sound insulation structure 50 in the Z+ direction can be attenuated, and the sound insulation performance of the sound insulation structure 50 is improved. On the other hand, the larger the interval, the larger the opening, so that the flow rate of fluid or objects passing through the sound insulation structure 50 in the Z+ direction can be increased. As a result, when the sound insulation structure 50 constitutes the boundary of the space, there is an advantage that the ventilation performance, exhaust heat performance, fire prevention performance, and light transmittance performance (for example, daylighting performance) of the space are improved. Further, by making the interval constant, it is less likely to generate a portion where the transmission loss is locally small (that is, sound is likely to leak), and a stable sound insulation performance can be exhibited.

[0025] (3) Configuration of the sound insulation system The configuration of the sound insulation system of this embodiment will be described. Fig. 5 is a diagram conceptually showing a partition facility provided with the sound insulation system of this embodiment.

[0026] As shown in Fig. 5, the partition facility 100 includes a sound insulation structure 50, an acoustic member 60, and a partition member 110. The partition facility 100 is a booth facility such as a semi-closed type work booth, for example.

[0027] The partition member 110 partitions a space. In the example of FIG. 5, the partition member 110 includes a floor member 110F that constitutes the vertical lower end portion of the partitioning facility 100 and wall members 110W that constitute the horizontal four-direction end portions of the partitioning facility 100. On the other hand, the vertical upper end portion of the partitioning facility 100 (that is, the opposing surface of the floor member 110F) does not include the partition member 110 and functions as an opening. Note that it is also possible to configure such that not the entire surface but a part of the vertical upper end portion of the partitioning facility 100 is blocked by the partition member 110.

[0028] The sound insulation system of the present embodiment is installed in a space (hereinafter referred to as "target space") surrounded by the partition member 110 and having an opening. The dimension of the opening is determined to be sufficiently larger than the wavelength corresponding to the sound insulation target frequency of each resonator constituting the sound insulation structure 50. In the example of FIG. 5, the vertical upper end portion of the target space corresponds to the opening. The sound insulation system of the present embodiment includes a sound insulation structure 50 and an acoustic member 60.

[0029] The sound insulation structure 50 is attached to a position on the inner surface of the partition member 110 that is closer to the opening of the target space than the acoustic member 60. In the example of FIG. 5, the sound insulation structure 50 is provided at the vertical upper end of the target space. More specifically, each sound insulation unit 10 constituting the sound insulation structure 50 is attached to the vertical upper end of the wall member 110W. The plurality of resonators constituting the sound insulation unit 10 are attached at intervals in a direction approaching the opening of the target space. Further, the sound insulation structure 50 is provided such that the Z+ direction of each sound insulation unit 10 constituting the sound insulation structure 50 is along the vertical upward direction. That is, the direction of the Z+ direction of each sound insulation unit 10 is adjusted so as to be along the direction in which the sound wave generated in the target space (for example, the sound generated by the speech or action of the user in the partition facility 100) propagates toward the opening of the partition facility 100. As a result, the sound generated in the target space is less likely to leak to the outside of the partition facility 100, so that the user can easily conduct a telephone call or a video conference on a highly confidential topic, and a person outside the partition facility 100 is less likely to feel uncomfortable with the sound generated inside the partition facility 100. Further, since the sound insulation structure 50 can take in the water of the sprinkler installed on the ceiling of the building through its upper end portion (top surface portion) in the vertical upward direction, it is not necessary to provide a fire extinguishing facility such as a sprinkler in the partition facility 100 itself. Further, by configuring the sound insulation structure 50 with a material having light transmissibility, the light of the lighting installed on the ceiling of the building can be taken into the partition facility 100.

[0030] The acoustic member 60 is attached to a position on the inner surface of the partition member 110 that is farther from the opening of the target space than the sound insulation structure 50. The acoustic member 60 exerts an acoustic action different from that of the inner surface of the partition member 110 (the location where the acoustic member 60 is attached) on the incident sound on the acoustic member 60.

[0031] Specifically, the acoustic member 60 is configured to suppress at least a component in the direction corresponding to specular reflection among the reflected sounds corresponding to the incident sound on the acoustic member 60 as compared with the case where the incident sound is reflected by the inner surface of the partition member 110 (the location where the acoustic member 60 is attached).

[0032] As an example, the acoustic member 60 includes a sound-absorbing material. The sound-absorbing material may be, for example, glass wool, or a resonant sound-absorbing material (which may include acoustic metamaterials) having one or more resonant frequencies, or other types of sound-absorbing materials. When the acoustic member 60 includes a resonant sound-absorbing material, any of the resonant frequencies of the sound-absorbing material may be preferably determined to substantially match the frequency of the sound insulation target of the sound insulation structure 50.

[0033] Sound waves incident on the sound insulation structure 50 from the Z - direction and transmitted in the Z+ direction are attenuated (i.e., receive a sound insulation effect) under the influence of resonance by the resonators constituting the sound insulation structure 50. In particular, when the extending direction (X - axis direction) of the resonator is orthogonal to the incident direction of the sound wave, the sound insulation structure 50 exhibits high sound insulation performance. On the other hand, when the angle formed by the extending direction of the resonator and the incident direction of the sound wave is small (i.e., when the sound wave is incident on the sound insulation structure 50 from an obliquely shallow direction), the sound insulation performance of the sound insulation structure 50 decreases, and the incident sound wave passes through the sound insulation structure 50 without being sufficiently attenuated. This is because the sound wave incident on each resonator of the sound insulation structure 50 propagates in the extending direction of the resonator, thereby inhibiting resonance. Such a phenomenon appears more prominently when the dimension of the extending direction of each resonator has a pipe structure longer than 1 / 2 times the wavelength corresponding to the sound insulation target frequency. In order to reduce the sound that is emitted from the inside of the partition facility 100 to the outside without being sufficiently soundproofed in this way, the soundproofing system includes an acoustic member 60 in addition to the soundproofing structure 50. The acoustic member 60 suppresses the energy of the reflected sound in each direction (including the direction corresponding to specular reflection) by absorbing part of the energy of the incident sound on the acoustic member 60 with a sound-absorbing material. In the example of FIG. 5, for example, the sound waves SW1, SW2, and SW3 radiated from the designed sound source SS enter the soundproofing structure 50 without being reflected by the acoustic member 60 or the partition member 110 (the inner surface of the partition member 110). Since the sound waves SW1, SW2, and SW3 enter the soundproofing structure 50 at an angle close to perpendicular, they are sufficiently soundproofed by the soundproofing structure 50. On the other hand, the sound waves SW4 and SW5 radiated from the designed sound source SS are absorbed by the acoustic member 60 and then enter the soundproofing structure 50. The incident angles of the sound waves SW4 and SW5 with respect to the soundproofing structure 50 are larger than those of the sound waves SW1, SW2, and SW3, but the sound waves SW4 and SW5 are attenuated by the acoustic member 60. Therefore, even if the sound waves SW4 and SW5 do not sufficiently receive the soundproofing effect of the soundproofing structure 50, the sound waves SW4 and SW5 emitted to the outside of the partition facility 100 are sufficiently smaller than when radiated from the sound source SS. In addition, when the frequency band in which the sound absorption rate by the acoustic member 60 shows a peak and the frequency band in which the transmission loss by the soundproofing structure 50 shows a peak (that is, the frequency band of the soundproofing target) overlap at least partially, the soundproofing system can more efficiently soundproof the sound of the soundproofing target frequency. That is, the sound emitted from the inside of the partition facility 100 to the outside can be more efficiently reduced.

[0034] Further, the acoustic member 60 may be attached to a position on the inner surface of the partition member 110 where there is a possibility of generating reflected sound that would enter the sound insulation structure 50 at an incident angle of a predetermined angle (e.g., 30 degrees) or more with respect to the sound insulation structure 50 if the acoustic member 60 were not attached. Such a position can be specified based on the shape of the inner surface of the partition member 110 (i.e., the target space), the possible positions and orientations of the sound source, and the sound radiation characteristics of the sound source. As a result, compared to the case where the acoustic member 60 is attached to the entire inner surface of the partition member 110, while reducing the required amount of the acoustic member 60, most of the incident angles of sound waves with respect to each resonator constituting the sound insulation structure 50 can be restricted within a predetermined range, so that the sound transmitted through the sound insulation structure 50 can be reduced.

[0035] Note that the installation directions and positions of the sound insulation unit 10, the sound insulation structure 50, and the acoustic member 60 in the partitioning facility 100 are not limited to the example shown in FIG. 5. For example, when the sound insulation structure 50 is installed near the upper end in the vertical direction of the partitioning facility 100, the orientation of the sound insulation structure 50 may be set such that the Z+ direction of the sound insulation unit 10 is oblique with respect to the vertical upward direction (i.e., neither perpendicular nor parallel). Thereby, it is possible to suppress foreign objects from vertically falling into the partitioning facility 100 from the ceiling of the building. Furthermore, it is also possible to suppress the thickness of the sound insulation structure 50 in the vertical upward direction when arranging the sound insulation units 10 with the same number and intervals. Also, an opening may be provided in at least a part of the wall member 110W behind the user, and the sound insulation structure 50 may be installed in the opening portion. Thereby, the sense of oppression felt by the user can be reduced. In this case, by setting the orientation of the sound insulation structure 50 such that the Z+ direction of the sound insulation unit 10 follows the direction behind the user, high air permeability can be maintained. Also, the acoustic member 60 may be attached to a position on the inner surface of the partition member 110 that is farther from the opening behind the user than the sound insulation structure 50. On the other hand, by setting the orientation of the sound insulation structure 50 such that the Z+ direction of the sound insulation unit 10 is oblique with respect to the direction behind the user, it becomes difficult to peek into the inside of the partitioning facility 100 from the outside of the partitioning facility 100, and privacy can be ensured.

[0036] Note that the partition facility 100 is not limited to the booth facility. For example, it may be an enclosure for a noise source such as a compressor or an outdoor unit. In any case, the partition member 110 is configured such that an end portion in any direction (not limited to the vertically upward direction) of the target space of the partition facility 100 is in a completely or partially open state. And the sound insulation structure 50 is provided at the end portion that is at least partially in an open state, and the orientation is adjusted so that the Z+ direction of each sound insulation unit 10 is along the direction in which sound propagates from the target space where the noise source exists to the external space through the opening. Also, the acoustic member 60 is attached to a position on the inner surface of the partition member 110 that is farther from the opening of the target space than the sound insulation structure 50. Thereby, it is possible to suppress the sound emitted from the noise source from leaking to the outside of the target space. Note that by installing each sound insulation unit 10 with its installation orientation rotated 180 degrees around the Y-axis or X-axis, it is also possible to suppress the sound that enters the target space from the outside through the opening. In this case, the acoustic member 60 may be attached to a position on the inner surface of the partition member 110 that is closer to the opening of the target space than the sound insulation structure 50.

[0037] (4) Parentheses The sound insulation system of the present embodiment is installed in a target space surrounded by the partition member 110 and having an opening. The sound insulation system includes an acoustic member 60 attached to the inner surface of the partition member 110, and the acoustic member 60 exerts an acoustic action different from that of the inner surface of the partition member 110 on the incident sound on the acoustic member 60. The sound insulation system includes a sound insulation structure 50 attached at a position closer to the opening than the acoustic member 60 and reducing the sound propagating from the inside to the outside of the target space. Thereby, since the sound wave that is reflected by the inner surface of the partition member 110 and obliquely incident on the sound insulation structure 50 at a shallow angle is suppressed by the acoustic action of the acoustic member 60, the sound passing through the sound insulation structure 50 can be efficiently reduced. That is, high sound insulation performance can be realized without completely closing the space.

[0038] The acoustic effect exerted by the acoustic member 60 may be an effect of suppressing at least the components in a specific direction among the reflected sounds corresponding to the incident sound. Thereby, since the sound propagating in this specific direction and incident on the sound insulation structure 50 is attenuated, it is possible to reduce the sound wave obliquely incident on the sound insulation structure 50 at a shallow angle.

[0039] The sound insulation structure 50 may include resonators 11, 12, and 13 having a pipe structure longer than half of the wavelength corresponding to the frequency of the sound insulation target. Thereby, the influence of the acoustic member 60 on the sound insulation performance of the sound insulation system is increased.

[0040] The sound insulation structure 50 may include a plurality of resonators 11, 12, and 13 attached at intervals in a direction approaching the opening. Thereby, it is possible to effectively block (reduce) the sound leaking from the target space to the external space.

[0041] The acoustic member may include a sound absorbing material. Thereby, it is possible to attenuate the reflected sound in a specific direction and suppress a decrease in the sound insulation performance of the sound insulation structure 50 caused by a sound wave obliquely incident on the sound insulation structure 50 at a shallow angle.

[0042] The acoustic member 60 may be attached to a position on the inner surface of the partition member 110 where there is a possibility of generating a reflected sound that will be incident on the sound insulation structure 50 at an incident angle equal to or greater than a predetermined angle. Thereby, while reducing the required amount of the acoustic member 60, most of the incident angles of the sound waves with respect to each resonator constituting the sound insulation structure 50 can be limited within a predetermined range, and the sound transmitted through the sound insulation structure 50 can be reduced.

[0043] The frequency band in which the transmission loss by the sound insulation structure 50 shows a peak (i.e., the frequency band of the sound insulation target) and the frequency band in which the sound absorption rate by the acoustic member 60 shows a peak may at least partially overlap. Thereby, the sound insulation system can more efficiently insulate the sound of the sound insulation target frequency. That is, it is possible to more efficiently reduce the sound emitted from the inside of the partitioned facility 100 to the outside.

[0044] The partition facility 100 of this embodiment may include a sound insulation system and a partition member 110. Thereby, the sound generated in the target space can be made less likely to leak to the outside.

[0045] The partition member 110 may be configured such that the upper end portion in the vertical direction of the target space is an opening. Thereby, for example, while being able to take in the light of the lighting provided on the ceiling of the building in which the partition facility 100 is installed and the water of the sprinkler, the sound generated in the target space can be made less likely to leak to the outside.

[0046] (5) Variation A variation of this embodiment will be described.

[0047] (5-1) Variation 1 Variation 1 will be described. Variation 1 is an example in which the acoustic member constituting the sound insulation system of this embodiment is configured to include a reflective material.

[0048] (5-1-1) Configuration of the sound insulation system The configuration of the sound insulation system of Variation 1 will be described. FIG. 6 is a diagram conceptually showing a partition facility provided with the sound insulation system of Variation 1.

[0049] As shown in FIG. 6, the partition facility 101 includes a sound insulation structure 50, an acoustic member 61, and a partition member 110. The partition facility 101 is a booth facility such as a semi-closed type work booth, for example.

[0050] The sound insulation system of Variation 1 is installed in the target space in the same manner as the sound insulation system of this embodiment. In the example of FIG. 6, the upper end portion in the vertical direction of the target space corresponds to the opening. The sound insulation system of Variation 1 includes a sound insulation structure 50 and an acoustic member 61.

[0051] The acoustic member 61 is attached to a position on the inner surface of the partition member 110 that is farther from the opening of the target space than the sound insulation structure 50. The acoustic member 61 exerts an acoustic action different from that of the inner surface of the partition member 110 on the incident sound on the acoustic member 61.

[0052] Specifically, the acoustic member 61 is configured to suppress at least a component in a direction corresponding to specular reflection among the reflected sounds corresponding to the incident sound on the acoustic member 61, as compared with the case where the incident sound is reflected by the inner surface of the partition member 110.

[0053] As an example, the acoustic member 61 includes a reflective material. A first example of the acoustic member 61 can include, as the reflective material, a member having a parabolic shape and having the direction of the reflected sound fixed (for example, the incident angle with respect to a specific resonator is 0 degrees or a value equal to or less than a predetermined angle) regardless of the direction of the incident sound. Alternatively, a second example of the acoustic member 61 can include, as the reflective material, a member that adjusts the reflection direction of sound by utilizing sound diffraction, refraction, or both. A third example of the acoustic member 61 can include, as the reflective material, a reflector whose position and orientation are adjusted according to the direction of a desired reflected sound. The shape of the reflective material may be designed according to at least one of the sound insulation target frequencies of the sound insulation structure 50.

[0054] The acoustic member 61 reflects the incident sound on the acoustic member 61 by the reflective material in a direction different from the specular reflection (that is, the reflection direction when the inner surface of the partition member 110 is substantially flat). More specifically, the acoustic member 61 is configured such that the incident angle of the reflected sound corresponding to the incident sound with respect to the sound insulation structure 50 (resonator constituting the sound insulation structure 50) is equal to or less than a predetermined angle (for example, 30 degrees). In the example of FIG. 6, for example, the sound waves SW1, SW2, and SW3 radiated from the designed sound source SS are incident on the sound insulation structure 50 without being reflected by the acoustic member 61 or the partition member 110 (inner surface of the partition member 110). On the other hand, the sound waves SW4 and SW5 radiated from the designed sound source SS have their reflection directions changed by the acoustic member 61 to directions different from those in the case of specular reflection, and then are incident on the sound insulation structure 50. The incident angles of the sound waves SW4 and SW5 with respect to the sound insulation structure 50 are closer to 0 degrees than when they are specularly reflected. Therefore, each resonator constituting the sound insulation structure 50 can appropriately exhibit the sound insulation function for each of the sound waves SW1 to SW5.

[0055] Further, the acoustic member 61 may be attached to a position on the inner surface of the partition member 110 where reflected sound that may be generated and incident on the sound insulation structure 50 at an incident angle of a predetermined angle (for example, 30 degrees) or more is likely to occur. Such a position can be specified based on the shape of the target space, the possible positions and directions of the sound source, and the sound radiation characteristics of the sound source. As a result, while reducing the required amount of the acoustic member 61 compared to the case where the acoustic member 61 is attached to the entire inner surface of the partition member 110, most of the incident angles of the sound waves on each resonator constituting the sound insulation structure 50 can be limited within a predetermined range, so that the sound transmitted through the sound insulation structure 50 can be reduced.

[0056] Note that the installation directions and positions of the sound insulation unit 10, the sound insulation structure 50, and the acoustic member 61 in the partition facility 101 are not limited to the example shown in FIG. 6. For example, when the sound insulation structure 50 is installed near the upper end portion in the vertical direction of the partition facility 101, the orientation of the sound insulation structure 50 may be set such that the Z+ direction of the sound insulation unit 10 is inclined with respect to the vertical upward direction (that is, neither perpendicular nor parallel). Thereby, it is possible to suppress foreign objects from vertically falling into the partition facility 101 from the ceiling of the building. Furthermore, it is also possible to suppress the thickness of the sound insulation structure 50 in the vertical upward direction when arranging the sound insulation units 10 with the same number and interval. In addition, at least a part of the wall member 110W behind the user may be provided with an opening, and the sound insulation structure 50 may be installed in the opening portion. Thereby, the sense of oppression felt by the user can be reduced. In this case, by setting the orientation of the sound insulation structure 50 such that the Z+ direction of the sound insulation unit 10 follows the direction behind the user, good air permeability can be maintained. Further, the acoustic member 61 may be attached to a position on the inner surface of the partition member 110 that is farther from the opening behind the user than the sound insulation structure 50. On the other hand, by setting the orientation of the sound insulation structure 50 such that the Z+ direction of the sound insulation unit 10 is inclined with respect to the direction behind the user, it becomes difficult to peek into the inside of the partition facility 101 from the outside of the partition facility 101, and privacy can be ensured.

[0057] Note that the partition facility 101 is not limited to the booth facility. For example, it may be an enclosure for noise sources such as compressors and outdoor units. In any case, the partition member 110 is configured such that at least one end in any direction (not limited to the vertically upward direction) of the target space of the partition facility 101 is in a completely or partially open state. And the sound insulation structure 50 is provided at the end that is at least partially in an open state, and the Z+ direction of each sound insulation unit 10 is adjusted to be along the direction in which sound propagates from the target space where the noise source exists to the external space through the opening. Also, the acoustic member 61 is attached to a position on the inner surface of the partition member 110 that is farther from the opening of the target space than the sound insulation structure 50. Thereby, it is possible to suppress the sound emitted from the noise source from leaking to the outside of the target space. Note that by installing each sound insulation unit 10 with its installation direction rotated 180 degrees around the Y axis or the X axis, it is also possible to suppress the sound that enters the target space from the outside through the opening. In this case, the acoustic member 61 may be attached to a position on the inner surface of the partition member 110 that is closer to the opening of the target space than the sound insulation structure 50.

[0058] (5-1-2) Parentheses The acoustic member 61 of Modification 1 includes a reflective material that reflects the incident sound in a direction different from the inner surface of the partition member 110. Thereby, the incident angle of the sound with respect to the sound insulation structure 50 is adjusted, and the resonator constituting the sound insulation structure 50 can appropriately exhibit the sound insulation function. That is, it is possible to achieve both air permeability and sound insulation.

[0059] The reflective material may be configured such that the incident angle of the reflected sound corresponding to the incident sound with respect to the sound insulation structure 50 is equal to or less than a predetermined angle. Thereby, the sound incident on the sound insulation structure 50 at an incident angle exceeding the predetermined angle is reduced, and the resonator constituting the sound insulation structure 50 can more appropriately exhibit the sound insulation function.

[0060] (5-2) Modification 2 Modification 2 will be described. Modification 2 is an example in which at least one of the resonators constituting the sound insulation structure of the present embodiment or Modification 1 has a node structure (a structure divided into a plurality of compartments).

[0061] (5-2-1) Configuration of the resonator The configuration of the resonator according to Modification 2 will be described. FIG. 7 is a view of the resonator according to Modification 2 as seen from the Z-direction.

[0062] As shown in FIG. 7, the resonator 20 is a continuum extending in the X-axis direction. Further, the resonator 20 has a shape in which an end portion in the -Z direction of the side surface of a hollow cylinder extending in the X-axis direction is cut out so that the internal space and the external space can communicate with each other. The resonator 20 has a tube structure in which the dimension in the X-axis direction is shorter than N (N is an integer of 2 or more) times 1 / 2 of the wavelength corresponding to the sound insulation target frequency of the resonator 20. The resonator 20 includes partition portions 20P-1 to 20P-4 that divide this tube structure into N (in the example of FIG. 7, N is 5) sections 20S-1 to 20S-5 arranged in the X-axis direction (that is, the longitudinal direction of the tube structure). The dimension of the section 20S in the X-axis direction is shorter than 1 / 2 times the wavelength corresponding to the sound insulation target frequency of the resonator 20. The partition portion 20P shields the boundary between the two spaces so that sound waves do not propagate between the internal spaces of two adjacent sections 20S separated by the partition portion 20P. The section 20S is configured to resonate at the sound insulation target frequency of the resonator 20. Specifically, the section 20S has a C-shaped cross-sectional shape in any plane orthogonal to the X-axis and functions as a Helmholtz resonator. The section 20S transmits a secondary wave having a phase opposite to that of the incident wave. The primary wave of sound that directly passes through the gap of the resonator is attenuated by interfering with the secondary wave generated and transmitted by resonance. The resonator 20 can be used as any one of the resonators 11 to 13 described above, or as any one of the resonators constituting the sound insulation unit 10.

[0063] In order to enhance the light transmittance of the sound insulation unit 10, the resonator 20 and the partition portion 20P may be made of a material having light transmittance (for example, a transparent or translucent resin material such as glass or acrylic). However, since the sound insulation unit 10 exhibits sound insulation performance due to its structure, there is a high degree of freedom in the selection of materials, and it can be composed of various materials such as resin, metal, silicon, rubber, polymer, paper, cardboard, wood, or non-woven fabric. Therefore, it is possible to impart sound insulation performance to an existing housing or to configure it as an environmentally considerate member by utilizing thinned wood or recycled materials.

[0064] Each section of the resonator 20 is configured to resonate at a specific frequency. The resonance frequency depends on the radial thickness of the resonator 20 (section 20S) (that is, the difference between the outer radius and the inner radius), the circumferential width of the notch (slit) of the resonator 20 (section 20S), and the internal cross-sectional area of the hollow cylinder. Specifically, the resonance frequency is proportional to the square root of the value obtained by dividing the slit width by the product of the thickness and the internal cross-sectional area.

[0065] In addition, when configuring the sound insulation unit 10 to include a plurality of resonators 20 having different resonance frequencies, the dimension of the section 20S of each resonator 20 in the X-axis direction may be determined according to the resonance frequency of the resonator 20 (section 20S) (for example, in inverse proportion). Thereby, the dimension of the section 20S can be optimized. On the other hand, the dimension of the section 20S of the resonator 20 in the X-axis direction may be determined to be the same regardless of the resonance frequency of the resonator 20 (section 20S). Thereby, since the positions of the partition portions 20P are aligned among the different resonators 20, the unity of the design of the sound insulation unit 10 can be enhanced.

[0066] The resonator 20 of Modification 2 includes a partition portion 20P that divides the tube structure into a plurality of compartments 20S arranged in the longitudinal direction of the tube structure, and each of the plurality of compartments 20S is configured to resonate at the frequency of the sound insulation target. Thereby, since the distance that the sound incident on the resonator 20 propagates in the extending direction (X-axis direction) of the resonator 20 can be limited to the dimension of the compartment 20S, the resonator 20 can appropriately exhibit the sound insulation effect. That is, it is possible to achieve both air permeability and sound insulation. Further, by including the compartment 20S, the resonator 20 has improved rigidity and suppressed film vibration.

[0067] (6) Other Modifications In the above description, an example in which the resonance frequencies of the resonators included in the sound insulation unit are different has been shown. However, the resonance frequencies of some or all of the resonators included in the sound insulation unit may be the same. By resonating a plurality of resonators at the same frequency, it is possible to further increase the transmission loss in the vicinity of the frequency. Similarly, the resonance frequencies of some or all of the resonators included in the sound insulation unit may be the same as the frequency depending on the interval between the aforementioned resonators.

[0068] In the above description, an example in which the sound insulation structure 50 is attached to the unclosed opening of the compartment facility 100 partitioned by the partition member 110 and the acoustic member 60 (or the acoustic member 61) is attached at a more distant position has been shown. However, the uses and installation methods of the sound insulation structure 50 (or the sound insulation unit 10, the sound insulation unit 30, or the sound insulation unit 40) and the acoustic member 60 (or the acoustic member 61) are not limited to this. For example, when arranging a sound insulation system in a room having a window as an opening, the sound insulation structure 50 may be attached to the window, and the acoustic member 60 (or the acoustic member 61) may be attached to the wall of the room. Further, for example, the sound insulation structure 50 may be attached to the window, and the acoustic member 60 (or the acoustic member 61) may be attached to an enclosure member installed so as to surround the periphery of the window. With such a configuration, while allowing ventilation through the window, it is possible to suppress the sound in the room from leaking out through the window.

[0069] In the above description, an example of a resonator having a shape in which an end portion in the sound propagation direction is cut out from the side surface of a hollow cylinder to enable communication between the internal space and the external space was shown. However, the present embodiment or the modification is not limited to a resonator having such a shape, and resonators having any shape can be adopted.

[0070] Although not shown in the above description, each resonator constituting the sound insulation unit of the present embodiment or the modification may be supported by a support. Specifically, as shown in FIGS. 8 and 9, the sound insulation unit of the present embodiment or the modification can be deformed into a sound insulation unit 230. The sound insulation unit 230 includes resonators 231, 232, 233, 234, 235, 236, 237, and 238 arranged side by side at intervals of Tz1 along the Z+ direction, and a support 240. The resonators 231, 232, 233, 234, 235, 236, 237, and 238 all have the shape of a hollow hexagonal prism. At least one of the resonators 231, 232, 233, 234, 235, 236, 237, and 238 may be configured to include a plurality of compartments in the same manner as the resonator 20 of the second modification. The resonators 231, 233, 235, and 237 are provided with slits at their ends in the Y+ direction to enable communication between the internal space and the external space. On the other hand, the resonators 232, 234, 236, and 238 are provided with slits at their ends in the Y− direction to enable communication between the internal space and the external space. The support 240 extends in the Z-axis direction and supports the resonators 231, 232, 233, 234, 235, 236, 237, and 238. As shown in FIG. 9, the sound insulation unit 230 may include a plurality of supports 240 along the X-axis direction. At least one of the supports 240 may be used also as the partition portion 20P of the second modification.

[0071] In the above description, an example in which each resonator is configured as a continuum extending in the X-axis direction has been described. The resonator configured as a continuum is advantageous in terms of high manufacturability and ease of attachment. However, it is also possible to arrange a plurality of resonators configured such that the dimension in the X-axis direction is smaller than that of such a resonator in the X-axis direction. In this case, a gap may be provided between a plurality of resonators adjacent to each other in the X-axis direction. Thereby, fluid (for example, air or water), light, or other objects can flow through the gap between a plurality of resonators adjacent to each other in the X-axis direction. In order to enhance the light transmissibility of the sound insulation unit 10, the sound insulation unit 30, or the sound insulation unit 40, each resonator may be made of a material having light transmissibility. Further, the interval between resonators adjacent to each other in the X-axis direction can be arbitrarily determined. The smaller the interval, the higher the sound insulation performance of the sound insulation unit 10, the sound insulation unit 30, or the sound insulation unit 40. On the other hand, the larger the interval, the larger the opening. Therefore, when the sound insulation unit 10, the sound insulation unit 30, or the sound insulation unit 40 constitutes the boundary of the space, there is an advantage that the ventilation performance, the exhaust heat performance, the fire prevention performance, and the light transmissibility (for example, daylighting performance) of the space are improved.

[0072] The sound insulation unit described in this embodiment or modification exhibits high transmission loss in a desired frequency band by designing the resonance frequency of the resonator and the arrangement interval of the resonators. Specifically, by dispersing the resonance frequencies of a plurality of resonators over a wide frequency band, the sound insulation unit can be designed to exhibit high sound insulation performance evenly from the low band to the wide band. Further, by concentrating the resonance frequencies of a plurality of resonators in a narrow frequency band or reducing the difference between the resonance frequency of an individual resonator and the frequency depending on the arrangement interval of the resonators, the sound insulation unit can be designed to exhibit particularly high sound insulation performance in a specific frequency band. As an example, by designing the sound insulation unit so that the transmission loss at 500 to 1000 Hz increases, the volume of the voice of a person passing through the sound insulation unit can be effectively reduced. As another example, by designing the sound insulation unit so that the transmission loss at 1000 to 8000 Hz (preferably 1000 to 4000 Hz, more preferably 1000 to 2000 Hz) increases, the clarity of the voice of a person passing through the sound insulation unit can be effectively reduced. Specifically, a person outside the space (e.g., a work booth) separated by the sound insulation unit has difficulty hearing the consonants uttered by a person inside the space, so that it is possible to recognize that someone is talking inside the space but impossible to recognize what is being said.

[0073] In the above example, an example in which the partitioning facility 100 (or the partitioning facility 101) is a booth facility has been described. However, the partitioning facility 100 may be any of the following. · A soundproof case surrounding a machine as a noise source · A cage for animals · A tunnel · A room in a building (where the window corresponds to the opening) · A private toilet

[0074] The acoustic member 60 of the present embodiment and the acoustic member 61 of the first modification example may be used in combination. When a small structure is adopted as the reflector constituting the acoustic member 61, it may be difficult to reflect the incident low-frequency sound in a desired direction. By using the acoustic member 60 and the acoustic member 61 in combination, for example, the incident low-frequency sound is absorbed, and the incident high-frequency sound changes the direction of the reflected sound, thereby suppressing the sound wave incident on the sound insulation structure 50 at a shallow angle, and the sound insulation structure 50 can exhibit an appropriate sound insulation effect.

[0075] In the above description, an example in which the interval between the resonators constituting the sound insulation unit is set to a specific value is shown. However, such an interval can also be arbitrarily determined. However, in this case, there is a possibility that the effect of maximizing the transmission loss at the frequency depending on the interval cannot be obtained.

[0076] As described above, the embodiments of the present invention have been described in detail, but the scope of the present invention is not limited to the above embodiments. Further, the above embodiments can be variously improved and modified without departing from the gist of the present invention. Further, the above embodiments and modification examples can be combined.

Explanation of Reference Numerals

[0077] 10: Sound insulation unit 11: Resonator 12: Resonator 13: Resonator 20: Resonator 50: Sound insulation structure 60: Acoustic member 61: Acoustic member 100: Compartment equipment 101: Compartment equipment 110: Partition member 230: Sound insulation unit 231: Resonator 232: Resonator 233: Resonator 234: Resonator 235: Resonator 236: Resonator 237: Resonator 238: Resonator 240: Support

Claims

1. A sound insulation system installed in a target space surrounded by partition members and having an opening, an acoustic member attached to the inner surface of the partition member, the acoustic member having an acoustic effect different from that of the inner surface of the partition member on the incident sound on the acoustic member, a sound insulation structure attached at a position closer to the opening than the acoustic member, for reducing the sound propagating from the inside to the outside of the target space and comprising a sound insulation system.

2. The acoustic effect exerted by the acoustic member is an effect of suppressing at least a component in a specific direction among the reflected sounds corresponding to the incident sound. The sound insulation system according to claim 1.

3. The sound insulation structure includes a resonator having a pipe structure longer than half the wavelength corresponding to the frequency of the sound insulation target. The sound insulation system according to claim 1.

4. The sound insulation structure includes a plurality of the resonators attached at intervals in a direction approaching the opening. The sound insulation system according to claim 3.

5. The sound insulation structure includes a partition portion that divides the pipe structure into a plurality of sections arranged in the longitudinal direction of the pipe structure. Each of the plurality of sections is configured to resonate at the frequency of the sound insulation target. The sound insulation system according to claim 3.

6. The acoustic member includes a sound-absorbing material. The sound insulation system according to claim 1.

7. The acoustic member is attached to a position on the inner surface of the partition member where there is a possibility of generating a reflected sound that will enter at an incident angle of a predetermined angle or more with respect to the sound insulation structure. The sound insulation system according to claim 6.

8. The frequency band in which the transmission loss by the sound insulation structure shows a peak and the frequency band in which the sound absorption rate by the sound absorption material shows a peak overlap at least partially. The sound insulation system according to claim 6.

9. The acoustic member includes a reflector that reflects the incident sound in a direction different from the inner surface of the partition member. The sound insulation system according to claim 1.

10. The acoustic member is configured such that the incident angle of the reflected sound corresponding to the incident sound with respect to the sound insulation structure is equal to or less than a predetermined angle. The sound insulation system according to claim 9.

11. The sound insulation system according to any one of claims 1 to 10, and the partition member Comprising a compartment facility.

12. The partition member is configured such that the upper end portion in the vertical direction of the target space becomes the opening. The compartment facility according to claim 11.

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