US-12620384-B2 - Sound-blocking sheet member, sound-blocking structure using same, and method for manufacturing sound-blocking sheet member

US12620384B2US 12620384 B2US12620384 B2US 12620384B2US-12620384-B2

Abstract

An object of the present invention is to provide a resonator that is relatively lightweight, has high sound-blocking performance overwhelming the law of mass action, and is excellent in terms of manufacturability and durability. The resonator includes at least a sheet and at least one resonance portion. The resonance portion is provided in contact with a sheet surface of the sheet, and the resonance portion includes a weight portion and a base portion. The weight portion is supported by the base portion and has a larger mass than the base portion, and the weight portion has a penetration portion. The base portion is in contact with a surface on a resonance portion front end side of the weight portion and covers the weight portion.

Inventors

Katsuhiko Sugiura
Shogo KOGA
Naoyuki Uchida
Kazuma Inoue
Yukio Kato
Kohji UEHARA
Masashi Miura

Assignees

MITSUBISHI CHEMICAL CORPORATION

Dates

Publication Date: 20260505
Application Date: 20240508
Priority Date: 20180906

Claims (20)

1 . A resonator, comprising: a sheet; and at least one resonance portion, wherein the at least one resonance portion is provided in contact with a sheet surface of the sheet, the at least one resonance portion includes a weight portion and a base portion, the weight portion is supported by the base portion and has a larger mass than the base portion, the weight portion has a penetration portion, and the base portion is in contact with a surface on a resonance portion front end side of the weight portion and covers the weight portion.
2 . The resonator according to claim 1 , wherein an outer peripheral portion of the weight portion and the inside of the penetration portion are filled with the base portion.
3 . The resonator according to claim 1 , wherein the weight portion is disposed on the front end side of the center in the height direction of the at least one resonance portion.
4 . The resonator according to claim 1 , wherein a maximum height from the opposite surface of the sheet surface provided with the at least one resonance portion to the front end of the at least one resonance portion is 30 mm or less.
5 . The resonator according to claim 4 , wherein the maximum height from the opposite surface of the sheet surface provided with the resonance portion to the front end of the resonance portion is 20 mm or less.
6 . The resonator according to claim 1 , wherein the at least one resonance portion has a void in which the surface on the front end side of the at least one resonance portion is indented, and the void is formed in the penetration portion.
7 . The resonator according to claim 1 , wherein the penetration portion is a through-hole.
8 . A structure, comprising the resonator according to claim 1 .
9 . A resonator, comprising: a sheet; and at least one resonance portion, wherein the at least one resonance portion is provided in contact with a surface of the sheet, each at least one resonance portion includes a weight portion and a base portion, the weight portion is supported by the base portion and has a larger mass than the base portion, and the weight portion has a penetration portion.
10 . The resonator according to claim 9 , wherein an outer peripheral portion of the weight portion and the inside of the penetration portion are filled with the base portion.
11 . The resonator according to claim 10 , wherein a maximum height from the opposite surface of the sheet surface provided with the at least one resonance portion to the front end of the resonance portion is 30 mm or less.
12 . The resonator according to claim 11 , wherein the maximum height from the opposite surface of the sheet surface provided with the at least one resonance portion to the front end of the resonance portion is 20 mm or less.
13 . A structure, comprising the resonator according to claim 9 .
14 . A method for manufacturing a resonator having a sheet portion, at least one protrusion portion provided in the surface direction of the sheet portion, and a weight portion provided on a front end side of the at least one protrusion portion, the method comprising: a weight portion insertion step of inserting the weight portion into a bottom portion of at least one cavity, in which the at least one protrusion portion is to be molded, in a mold including the at least one cavity; and a resin insertion step of pouring a resin into the at least one cavity, wherein a projection portion is provided at one of the bottom portion and the front end side of the weight portion, and a recessed portion or a penetration portion into which the projection portion is to be inserted is provided at the other, wherein a projection portion is provided at the bottom portion of the at least one cavity, a recessed portion or a penetration portion into which the projection portion is to be inserted is provided at the weight portion, in the weight portion insertion step, the projection portion is inserted into the recessed portion or the penetration portion, and in the resin insertion step, in a state in which the projection portion is inserted into the recessed portion or the penetration portion and a position in the surface direction of the weight portion with respect to the bottom portion is regulated, the resin is poured into the at least one cavity.
15 . The method for manufacturing a resonator according to claim 14 , wherein the weight portion has the penetration portion.
16 . The method for manufacturing a resonator according to claim 15 , wherein the bottom portion is provided with the projection portion and a step portion that protrudes to a height lower than the projection portion and is in contact with a part of the surface on the front end side of the weight portion.
17 . The method for manufacturing a resonator according to claim 16 , wherein the step portion is provided in contact with the side surface of the projection portion.
18 . The method for manufacturing a resonator according to claim 16 , wherein the step portion is provided apart from the side surface of the projection portion.
19 . The method for manufacturing a resonator according to claim 17 , wherein the step portion inclines in a direction in which the height decreases as the protrusion portion runs from the central side in the radial direction toward the outer side in the radial direction, and the maximum diameter of the step portion at a highest position is smaller than the hole diameter of the penetration portion provided in the weight portion, and a maximum diameter of the step portion at the lowest position is larger than the hole diameter of the penetration portion.
20 . The method for manufacturing a resonator according to claim 14 , wherein the mold includes a lower mold having cavities provided in an open state on an upper surface, and an upper mold that is movable between a position at which the upper mold comes into contact with the upper surface of the lower mold and a position at which the upper mold is spaced apart from the lower mold on an upper side and has an indentation provided on the upper surface and a penetration flow path that is open in the indentation, and in the resin insertion step, in a state in which the upper mold and the lower mold are in contact with each other, a molten resin is poured into the at least one cavity from the indentation through the penetration flow path.

Description

This application is a Continuation Application of prior U.S. application Ser. No. 17/191,792, filed Mar. 4, 2021, the contents of which are incorporated herein by reference. U.S. application Ser. No. 17/191,792 is based on International Application No. PCT/JP2019/034966, filed Sep. 5, 2019, which claims priority on Japanese Patent Application No. 2018-166867 filed on Sep. 6, 2018, and Japanese Patent Application No. 2019-148471 filed on Aug. 13, 2019, the contents of both of which are incorporated herein by reference. TECHNICAL FIELD The present invention relates to a sound-blocking sheet member, a sound-blocking structure using the same, and a method for manufacturing a sound-blocking sheet member. BACKGROUND ART In buildings such as complex housing, office buildings, and hotels, there is a demand for quietness suitable for room applications which is attained by blocking outdoor noise from automobiles, railroads, aircraft, ships, and the like, equipment noise generated inside buildings, or human voice. In addition, in vehicles such as automobiles, railroads, aircrafts, and ships, there is a demand for the reduction of indoor noise in order to provide quiet and cozy spaces to occupants by blocking wind noise or engine noise. Therefore, research and development of means for blocking the propagation of noise or vibration from outdoor places to indoor places or from the outside to the inside of vehicles, that is, vibration-damping and sound-blocking means has been underway. In recent years, in response to the verticalization or the like of buildings, there has been a demand for a lightweight vibration-damping and sound-blocking member, and, for vehicles as well, there has been a demand for a lightweight vibration-damping and sound-blocking member for improving energy efficiency. Furthermore, in order to improve the degree of freedom in designing buildings, vehicles, and equipment thereof, there is a demand for a vibration-damping and sound-blocking member capable of dealing with complicated shapes. Ordinarily, the characteristics of vibration-damping and sound-blocking materials follow the so-called a law of mass action. That is, the transmission loss, which is an index of the amount of noise reduction, is determined by the logarithm of the product of the mass of a vibration-damping and sound-blocking material and the frequency of an elastic wave or a sound wave. Therefore, in order to increase the amount of noise reduction at a certain frequency, it is necessary to increase the mass of the vibration-damping and sound-blocking material. However, methods for increasing the masses of vibration-damping and sound-blocking materials have limitations on the amount of noise reduction due to restrictions on the masses of buildings, vehicles, or the like. In order to solve the problem with an increase in the masses of vibration-damping and sound-blocking members, the structures of the members have been thus far improved. For example, a method in which a plurality of stiff flat plate materials such as gypsum boards, concrete, steel plates, glass plates, or resin plates are combined and used, a method in which a hollow double-wall structure or a hollow triple-wall structure is produced using gypsum boards or the like, or the like is known. In addition, recently, in order to realize sound-blocking performance overwhelming the law of mass action, a sound-blocking plate made of a plate-like acoustic metamaterial for which a high-stiffness flat plate material and a resonator are combined and used has been proposed. Specifically, sound-blocking plates having a plurality of independent stump-shaped protrusions (resonators) made of silicone rubber and tungsten or a plurality of independent stump-shaped protrusions (resonators) made of rubber provided on an aluminum substrate (refer to Non-Patent Documents 1 and 2), a sound-blocking plate having a plurality of independent stump-shaped protrusions (resonators) made of silicone rubber or silicone rubber and lead cap provided on an epoxy substrate (refer to Non-Patent Document 3) have been proposed. In addition, a sound-blocking sheet member including a sheet having rubber elasticity and a resonance portion having a base portion and a weight portion has been proposed (Patent Document 1). CITATION LIST Patent Document Patent Document 1 PCT International Publication No. WO 2017/135409 Patent Document 2 Japanese Unexamined Patent Application, First Publication No. 2000-265593 Non-Patent Document Non-Patent Document 1 M B Assouar, M. Senesi, M. Oudich, M. Ruzzene and Z. Hou, Broadband plate-type acoustic metamaterial for low-frequency sound attenuation, Applied Physics Letters, 2012, volume 101, pp 173505. Non-Patent Document 2 M. Oudich, B. Djafari-Rouhani, Y. Pennec, M. B. Assouar, and B. Bonello, Negative effective mass density of acoustic metamaterial plate decorated with low frequency resonant pillars, Journal of Applied Physics, 2014, volume 116, pp 184504. Non-Patent Document 3