Abstract: A compressor muffler (100) for a refrigeration system is provided with an array of Helmholtz resonators (130, 230, 330) formed along an inner surface of a muffler chamber (110) of the muffler.

Abstract: A moldable acoustic facing comprises cellulosic fibers and synthetic fibers entangled together. The acoustic facing has a basis weight of from about 1.5 to about 5.0 ounces per square yard (osy), a thickness of less than about 0.050?, a mean pore size of between about 8 microns and about 40 microns, and an elongation at break of at least twenty percent. The acoustic facing includes less than about five percent synthetic microfiber and has an acoustic resistance of at least about 250 Rayls.

Abstract: Sound insulating glazing device for aircrafts, ground or maritime transportation vehicles, buildings, or others, including glazing, a sealing joint in a shape and size corresponding to the edge of the glazing and designed for assembly on said edge, sound insulation, made of at least two materials, a first resilient material and a second material with less resilience than the first, the sound insulation being used against the field of said glazing, between the glazing and the sealing joint. The invention is also for aircrafts that are equipped with at least a glazing device and a soundproofing method for glazing.

Abstract: A method for producing a sound-deadening insert of a silencer of an exhaust-gas discharge system in an internal-combustion engine of a vehicle; the method comprises the steps of providing a mattress made up of continuous voluminized fibres of sound-deadening material, and needling the mattress so as to cause a compacting/interweaving of the fibres in order to obtain compacting lines.

Abstract: Two sheets of nonwoven fabric with the same shape and size each including a rectangular body 11a and a funnel-shaped projection 11b projecting from one side of the body 11a are stacked, and bonded together by heat welding at each side of the body 11a except the projection 11b and both sides of the projection 11b. Joint portions 13a, 13b, 13c, and 13d projecting inward from a joint 13 are located on three sides and four corners of the body 11a except the side provided with the projection 11b, and project to depths at which the joints do not interfere insertion of a nozzle 16 into a center portion of the bag. The nozzle 16 is inserted through an opening 15 of the projection 11b, and the bag is filled with a granular elastic material 12. Then, the projection 11b is removed, and the opening is closed.

Abstract: The invention describes a method for making a composite panel and the product made by the method. The composite panel is made from a soft septum treated with a composition containing silane and an organic acid. The treated soft septum is adhesively bonded between two honeycomb panels, forming a sandwich of the septum between the two honeycomb panels.

Abstract: The invention relates to a soundproofing device for the passenger compartment of a vehicle (10), to be positioned between a sheet métal panel of the vehicle bodywork (12) and an inner trimming panel (14). The device comprises a polymer foam plate (20) impregnated with a mixture of an inorganic filler and an organic binder, the foam plate (20) being shaped so as to be in close contact with the sheet métal panel of the bodywork (12) and with the inner trimming panel (14). The invention further relates to an inner trimming System for the passenger compartment of a vehicle, comprising an inner trimming panel (14) for covering a sheet métal panel of the vehicle bodywork (12) and such a device. The invention further relates to a vehicle provided with such a System. The invention can be used in automobiles.

Abstract: An acoustic suppression system for absorbing and/or scattering acoustic energy comprising a plurality of acoustic targets in a containment is described, the acoustic targets configured to have resonance frequencies allowing the targets to be excited by incoming acoustic waves, the resonance frequencies being adjustable to suppress acoustic energy in a set frequency range. Methods for fabricating and implementing the acoustic suppression system are also provided.

Abstract: The present invention provides a tunable sound absorption facing which includes a cellulosic web and a nonwoven web entangled together. The facing has a controllable air flow resistance.

Abstract: Panels for use in building construction (partitions, walls, ceilings, floors or doors) which exhibit improved acoustical sound proofing in multiple specific frequency ranges and also present improved structural integrity, are provided. The improved performance is achieved through the use of one or more layers of glue such that at least one layer of glue includes a viscoelastic material in a first pattern and a structural adhesive in a second, non-overlapping pattern. The viscoelastic material may have a varied shear moduli and functions as a glue and energy dissipating layer. In some embodiments, one or more constraining layers separating one layer of glue may be included. The constraining layer may be formed of a material such as gypsum, cement, metal, cellulose, wood, or petroleum-based products such as vinyl, plastic, or rubber. In some embodiments, standard wallboard, typically gypsum, comprises the external surfaces of the laminated panel.

Abstract: A moldable acoustic facing comprises cellulosic fibers and synthetic fibers entangled together. The acoustic facing has a basis weight of from about 1.5 to about 5.0 ounces per square yard (osy), a thickness of less than about 0.050?, a mean pore size of between about 8 microns and about 40 microns, and an elongation at break of at least twenty percent. The acoustic facing includes less than about five percent synthetic microfiber and has an acoustic resistance of at least about 250 Rayls.

Abstract: The object of the present invention is to provide a sound absorbing material having a light weight and excellent sound absorbing performance, and a sound absorbing material consisting of a fiber sheet made of fibers containing at least 50% by mass of a porous fiber having many minute pores, each minute pore opening onto the surface of the porous fiber, and having an airflow resistance in the range of between 0.05 and 3.0 kPa·s/m. The porous fiber having many minute pores, each one opening onto the surface of the porous fiber, has air-permeability, and so a sound absorbing property in itself, and a sheet made of the porous fiber having air-permeability and sound absorbing property has even further sound absorbing properties created by the spaces between the porous fibers, resulting in the sheet becoming a sound absorbing material with extremely great sound absorbing efficiency.

Abstract: An acoustic composite comprises a flow resistive substrate having a solid acoustic barrier material bonded to at least a portion of a major surface of the flow resistive substrate; wherein the acoustic barrier material has a density greater than about 1 g/cm3 and the acoustic composite has a porosity between about 0.002% and about 50%.

Abstract: An acoustic ceiling panel for a lay-in or suspended ceiling includes a core portion, and front and rear layers covering front and rear sides, respectively, of the core portion. The air flow resistance of the core portion does not exceed about 100 MKS rayls. The air flow resistance of the front layer lies in the range of about 300 to about 800 MKS rayls. The air flow resistance of the rear layer lies in the range of about 300 to about 1200 MKS rayls. The panel would be supported on a grid suspended below a structural ceiling to form an air space therebetween.

Abstract: A sound absorber is formed by covering the opening of a housing with a vibration member having a flat shape or a film shape so as to define an air layer therebetween. The sound absorber is attached to the wall of a room such that the vibration member is positioned opposite to the wall with a prescribed space therebetween. Sound generated in the room particularly in low frequencies enters into the space between the vibration member and the wall so as to cause vibration of the vibration member due to the pressure difference between the sound pressure applied to the space and the internal pressure of the air layer, thus consuming energy of sound waves. Thus, it is possible to efficiently absorb low-frequency sound with a reduced thickness of the air layer.

Abstract: An abuse-resistant, cast acoustical ceiling tile having improved impact resistance and excellent sound absorption values. The ceiling tiles have aggregate particles applied to the surface of a wet pulp in the casting process and the particles are embedded in the pulp by compression with a roll and/or smooth plates. The aggregate particles have an average particle diameter of at least about 1,000 microns. The ceiling tiles have excellent sound absorption properties with a noise reduction coefficient (NRC) of at least about 0.50. Calcium carbonate is the preferred aggregate particle material.

Abstract: The invention is directed at methods, materials, and articles for sound mitigation. The article for sound mitigation is a multi-layered composite article comprising a reinforcing substrate layer and a foam layer. The reinforcing substrate layer includes a fiber phase and a polymer phase. The fiber phase preferably includes one or more natural fibers. The natural fibers may be present at a concentration of about 60 wt. % or more, based on the total weight of the reinforcing substrate layer. The polymer phase is preferably a continuous phase and preferably has a glass transition temperature sufficiently high so that the panel maintains its stiffness at elevated temperatures. The concentration of the polymer phase may be about 10 wt. % or more, based on the total weight of the reinforcing substrate layer. Preferably both the foam layer and the reinforcing substrate layer are effective in reducing the transmission of a sound.

Abstract: An acoustically absorptive panel comprises a porous acoustical absorber having a planar configuration mounted on a support frame, an acoustically transparent front fabric stretch-mounted on the support frame and spaced from and in parallel alignment with the front face of the porous acoustical absorber and forming an airspace, the porous absorber, front fabric and forward air space acting as acoustical absorbing chamber capable of absorbing a greater range of sound frequencies than the porous acoustical absorber alone, the range of frequencies absorbed depending on the depth of the air space.

Abstract: A monolithically fabricated sound absorbing structural precast concrete noise barrier panel comprising a sound absorbing layer of specialized raw materials. The raw materials include wood particles as well as granulated rubber.

Abstract: A method of forming a monolithically fabricated sound absorbing structural precast concrete noise barrier panel comprising a sound absorbing layer of specialized raw materials. The method includes providing a sound absorbing layer that is a blended mixture of an aggregate, granulated rubber, chemically treated wood particles, cement, pozzolans, water, air entraining admixture, and water reducing mixture; placing the sound absorptive layer ingredients in a form mold; compressing the ingredients to a preset density; backing the compressed ingredients with reinforced structural concrete; and curing the backed and compressed ingredients.

Abstract: A sound insulation process comprises (a) providing at least one sound insulation device comprising at least one sound barrier comprising at least one substantially periodic array of structures disposed in a first medium having a first density, the structures being made of a second medium having a second density different from the first density, wherein one of the first and second media is a viscoelastic medium having a speed of propagation of longitudinal sound wave and a speed of propagation of transverse sound wave, the speed of propagation of longitudinal sound wave being at least about 30 times the speed of propagation of transverse sound wave, and wherein the other of the first and second media is a viscoelastic or elastic medium; and (b) interposing the sound insulation device between an acoustic source area and an acoustic receiving area of a transportation vehicle.

Abstract: Headliners for vehicles and vehicles incorporating the same are disclosed. In one embodiment, a vehicle includes an enclosed passenger compartment at least partially bounded by a roof structure. A headliner may be attached to an inboard side of the roof structure. The headliner may include an acoustical attenuator portion attached to an inboard side of the roof structure and an acoustical reflector portion attached to an inboard side of the acoustical attenuator portion. The acoustical attenuator portion absorbs acoustic energy incident on an outboard surface of the roof structure and the acoustical reflector portion reflects acoustic energy incident on an inboard side of the acoustical reflector portion. The enclosed passenger compartment has a Speech Transmission Index greater than 0.56 for acoustic energy incident on the inboard side of the acoustical reflector portion.

Abstract: Headliners for vehicles and vehicles incorporating the same are disclosed. In one embodiment, a vehicle includes an enclosed passenger compartment at least partially bounded by a roof structure. A headliner may be attached to an inboard side of the roof structure. The headliner may include an acoustical attenuator portion attached to an inboard side of the roof structure and an acoustical reflector portion attached to an inboard side of the acoustical attenuator portion. The acoustical attenuator portion absorbs acoustic energy incident on an outboard surface of the roof structure and the acoustical reflector portion reflects acoustic energy incident on an inboard side of the acoustical reflector portion. The enclosed passenger compartment has a Speech Transmission Index greater than 0.56 for acoustic energy incident on the inboard side of the acoustical reflector portion.

Abstract: A lithographic apparatus may be provided with an acoustic resonator to dampen an acoustic vibration in the lithographic apparatus. The acoustic resonator may include a Helmholtz resonator. The helmholz resonator may be provided with an active element to provide active damping and/or altering a spring characteristic of the mass spring assembly formed by the resonator. The resonator may be provided at a slit in a shield between the patterning device stage and the projection system to suppress transfer of acoustical vibrations, caused by e.g. a movement of the patterning device stage, to the projection system.

Abstract: The present invention relates to a process for producing a nanoporous foam, said process comprising providing a monomeric component (A) comprising a polyfunctional isocyanate (A1) and a solvent (C), and contacting said monomeric component (A) with water vapor. The present invention further comprises a nanoporous foam obtainable by such a process and also a nanofoam composite obtainable by applying said monomeric component (A) to a carrier (B) before the step of contacting with water vapor. The nanofoam composite is useful as insulant for thermal or acoustical insulation, as filtering material or as catalyst carrier.

Abstract: A monolithically fabricated sound absorbing structural precast concrete noise barrier panel comprising a sound absorbing layer of specialized raw materials. The raw materials include wood particles as well as granulated rubber.

Abstract: [Subject] The subject of the present invention is to provide a shock and sound absorbing material having a light weight, and demonstrating an excellent shock and sound absorbing performance. As a method for solving the subject, the present invention provides a shock and sound absorbing material 1 comprising a porous component 2, and a surface material 3 which is laminated onto the porous component 2, wherein the surface material 3 has at least one layer made of a stretchable paper material 5. The shock and sound absorbing material 1 is installed on a cover panel 7 covering a sound source such as an engine cover, and the porous component 2 is set so as to face the cover panel 7, with the surface material 3 being set so as to face the sound source, and form a cell structure between the cover panel 7 and the surface material 3.

Abstract: A method of installing an acoustical system that provides a desired sound attenuation includes attaching an acoustical panel having a first density, a first porosity and a first void volume to the substrate. A first finishing layer is prepared with first particles, a first binder, a first rheological modifier and water which are combined, applied to the substrate and dried. The first finishing layer has a first density. When the first sound attenuation changes to a second sound attenuation a second finishing layer is prepared to include second particles, a second binder, a second rheological modifier and water. The dried second finishing layer has a second density. If the second density is less than the first density, the second sound attenuation is greater than the first sound attenuation. If the second density is greater than the first density, the second sound attenuation is less than the first sound attenuation.

Abstract: An acoustic resistance member includes an air-shielding layer which does not allow air to pass through such that acoustic waves do not propagate, and an acoustic resistance layer which allows air to pass through such that acoustic waves propagate. The air-shielding layer is composed of a resin containing a coloring agent, and a part of the air-shielding layer is removed.

Abstract: An apparatus comprising a combination of a microphone and a composite acoustic panel. The composite acoustic panel comprises materials having different spectra of acoustic absorption. The materials may be integrated in a single layer or in a plurality of different layers.

Abstract: The present invention relates to a non-combustible, sound-absorbing facing (30) having an air flow resistivity of between 80 and 3,000 Rayls and a weight per unit area of between 20 and 1,000 g/m2 and to a laminate (10) comprising the facing (30) and a substrate (20) wherein superimposing the facing (30) on the substrate (20) forms the laminate (10) having good sound absorbing characteristics.

Abstract: This method includes the placing of the first porous layer (1) onto one part of a wall of a mold cavity having the shape desired by the soundproofing component, the first layer (1) not occupying the entire cavity, and the injection of a foaming polymer composition into the cavity of the mold to form the second open-cell porous layer (3). The two steps of placing the practically airtight intermediate layer (2) onto the first porous layer (1) and of injecting a polymer composition in order to form the second porous layer (3) are carried out simultaneously in a single step of injecting the foaming polymer composition.

Abstract: A vehicle flooring system with improved thermal and acoustic properties is provided that does not unreasonably increase the thickness and weight of the flooring system and does not break down due to repeated exposure to high temperatures and wide ranging temperature fluctuations. Various materials and construction methods are combined to provide a system with optimized thermal conductivity, having varied density ratios of materials to meet particular sound transmission loss profiles. These materials include a wide range of foam and other materials.

Abstract: An acoustic device and a method for altering sound. The acoustic device includes an architectural structure having a solid body. The architectural structure is adapted to be mounted on a wall of a room. The solid body has a channel therethrough to define a cavity therein. The channel is configured to alter sound waves incident on the acoustic device.

Abstract: A product including a web and a method of manufacturing such a product. The product may be for use as an industrial absorbent or a thermal or acoustic insulator and includes a web including scrap and/or recycled cellulose, the cellulose being selected from a source of post-industrial cellulose and/or a source of post-consumer cellulose, the cellulose being treated with a fire-retardant, the cellulose being dry before web formation, and opened, individuated bicomponent fibers mixed with the cellulose, at least some of the bicomponent fibers being thermally bonded to at least some of the cellulose. The method may include shredding the cellulose, declumping and sizing the cellulose, metering the cellulose into a spray booth, applying a fire retardant to the cellulose in the spray booth, if the fire retardant is a liquid, drying the cellulose, adding bicomponent fibers to the cellulose, forming a web, and heating the web in an oven.

Abstract: It is an object of the present invention to provide a solid-borne sound reducing structure which is able to reduce solid-borne sound with a simple configuration, highly durable, and being less degraded. There is provided a solid-borne sound reducing structure (100) in which a surface plate part (1) including a gas ventilating part (1a) which allows gas to pass through along a thickness direction is disposed by means of an outer peripheral wall part (2) on a structure (200) that radiates noise while vibrating, so as to at least partially cover a surface (200a) of the structure (200). The surface plate part (1) is supported by the outer peripheral wall part (2) so as to be integrally vibrated with the surface (200a) of the structure (200). In addition, the outer peripheral wall part (2) supports the surface plate part (1) in such a manner that an internal gas chamber is formed between the surface (200a) of the structure (200) and the surface plate part (1).

Abstract: An acoustical building panel and method of manufacturing it are disclosed. Embodiments of the panel include a porous nonwoven scrim, a coating deposited on the scrim, a base mat, and an adhesive deposited on either the base mat or the scrim in a discrete form such as in droplets. Embodiments of the method of manufacture include steps of perforating the base mat, applying the adhesive to the base mat in the discrete form, laminating the scrim onto the base mat, and applying the coating to the scrim surface.

Abstract: A low mass acoustically enhanced floor carpet system for vehicles. In a first embodiment, the carpet assembly comprising a face layer and an opposite lower fiber mat. The carpet assembly further including a primary backing if the face layer is tufted, a back coating layer, an upper fiber mat, and a perforated film layer all in between the face layer and the lower fiber mat. The perforated film layer providing for enhanced sound absorption. In an alternate embodiment, the carpet assembly comprising a face layer, an insulator pad opposite the face layer; a back coating, a perforated film layer, and an insulator pad all between the face layer and the insulator pad.

Abstract: A sound absorbing structure is constituted of a vibration plate and a rear air layer and is installed in a luggage compartment or trunk which is separated from a cabin in a vehicle. Sound waves entering into the luggage compartment drive the vibration plate to vibrate so that acoustic energy is converted into mechanical energy and is consumed by way of vibration of the vibration plate. By appropriately setting parameters and dimensions, the sound absorbing structure efficiently absorbs low-frequency sound such as road noise occurring due to friction of wheels of the vehicle traveling on a road.

Abstract: An acoustic resistor or damper and method of manufacturing the same is disclosed. The damper has mesh material and mounting material attached to the mesh material. The mounting material defines an open region for transmission of sound through the mesh material, and has a mounting surface for mounting the damper on a surface surrounding an acoustic port or tube. The mounting surface is located on a plane different from the mesh material, thereby shielding the mesh material from adhesive applied between the mounting surface and the surface surrounding the acoustic port or tube. The method of manufacturing an acoustic damper comprises a sheet of double-sided tape having at least one perforation applied to a mesh material. The double-sided tape and mesh material is cut in the shape surrounding the at least one perforation.

Abstract: An acoustic enhancement device adapted for being placed on a support and under a covering, and containing a first flexible layer adapted for being placed facing the support, a second rigid layer joined to the first flexible layer and adapted for being placed opposite the support, and a damping element, wherein the damping element is integrated in the second rigid layer or forms a third layer placed on the second rigid layer and opposite the first flexible layer.

Abstract: The present invention relates to a soundproof cover containing: a sound-absorbing material disposed facing to a sound source; a soft sound-insulating layer laminated on the sound-absorbing material and having an air permeability measured according to JIS L 1018 (1999) of 10 cc/cm2·sec or less; and a soft cover forming an air layer with the soft sound-insulating layer and having a Young's modulus measured according to JIS K 7127 (1999) of 0.2 to 1.5 GPa, in which the air layer is hermetically sealed.

Abstract: A sound insulation process comprises (a) providing at least one sound insulation device comprising at least one sound barrier comprising at least one substantially periodic array of structures disposed in a first medium having a first density, the structures being made of a second medium having a second density different from the first density, wherein one of the first and second media is a viscoelastic medium having a speed of propagation of longitudinal sound wave and a speed of propagation of transverse sound wave, the speed of propagation of longitudinal sound wave being at least about 30 times the speed of propagation of transverse sound wave, and wherein the other of the first and second media is a viscoelastic or elastic medium; and (b) interposing the sound insulation device between an acoustic source area and an acoustic receiving area of a transportation vehicle.

Abstract: It is an object of the present invention to provide an interlayer film for a laminated glass excellent in a sound-insulating property, which is preferably usable for a head up display and the like wherein a driver can look at the front view and an instrument display simultaneously without requiring to look down, and to provide a laminated glass. The present invention is directed to interlayer film for a laminated glass, which comprises at least a pair of protection layers and a sound-insulating layer sandwiched between the pair of the protection layers, and which has ah wedge shape as a cross-sectional shape, a wedge angle ? of 0.1 to 0.7 mrad, the maximum thickness of 2000 ?m or thinner, and the minimum thickness of 400 ?m or thicker, the minimum thickness of the sound-insulating layer being 20 ?m or thicker.

Abstract: A damping device and a method of damping a structural element of a vehicle body are disclosed. The damping device generally includes a carrier material, a separating material, and a damping material disposed on the carrier material. The damping material is one of a material forming an open cell structure and a material having an absorption coefficient for sound waves greater than about 0.5. The method generally includes fixing a damping device on a structural element of a vehicle, the damping device including a carrier material, a separating material, and a damping material, and one of expanding and dilating at least one of the separating material and the damping material, the damping material having one of an open cell structure and an absorption coefficient for sound waves greater than 0.5 after expansion.

Abstract: An acoustic damping composition includes a binder resin including an addition polymer having a carboxylic functional group and a urethane component. The acoustic damping composition has a Mode 1 Damping Parameter of at least 0.45.

Abstract: A passive distributed vibration absorber that utilizes multiple discrete mass elements and a viscoelastic layer and that effectively attenuates vibration in modally dense structures excited by a broadband input noise excitation. and is tunable to multiple natural frequencies in such modally dense vibrating structures including low frequencies.

Abstract: An apparatus and associated method for attenuating noise generated by a dishwashing appliance in operation is provided herein. During operation a dishwasher and its components generate thermo-acoustic waves associated with noise. A base tray comprising a major surface and an array of thermo-acoustic nodes are used to manage and control the thermo-acoustic waves. The array of thermo-acoustic nodes can be configured in a plurality of rows and columns with at least two thermo-acoustic nodes being interconnected. The array of thermo-acoustic nodes can be configured to channel the thermo-acoustic waves therebetween so as to control and manage the thermo-acoustic waves, thereby attenuating the noise associated with the thermo-acoustic waves. The base tray can be customizable with various arrangements of different thermo-acoustic nodes, clusters, stabilizers and/or channels.

Abstract: A composite headliner material allows sound waves originating within a vehicle to penetrate deeply into the headliner where all of a significant portion of their energy is absorbed rather than reflected back into the vehicle. The coverstock sheet is backed by a multilayer material with a foam core coated above and below by a fibrous glass mat impregnated with an adhesive with scrim layers above and below glass mat layers.

Abstract: A sound absorbing structure is constituted of a housing having a hollow portion and an opening and a vibration member composed of a board or diaphragm. The vibration member is a square-shaped material having elasticity composed of a synthetic resin and is bonded to the opening of the housing, thus forming an air layer closed inside the sound absorbing structure by the housing and the vibration member. In the sound absorbing structure, when the lateral/longitudinal dimensions of the air layer and characteristics of the vibration member (e.g. a Young's modulus, thickness, and Poisson's ratio) are set such that the fundamental frequency of a vibration occurring in a bending system falls within 5% and 65% of the resonance frequency of a spring-mass system, a vibration mode having a large amplitude occurs in a frequency band lower than the resonance frequency of the spring-mass system, this improving the sound absorption coefficient.