Perforation acoustic muffler assembly and method of reducing noise transmission through objects

• US 10,490,178 B2
• Filed: 04/18/2016
• Issued: 11/26/2019
• Est. Priority Date: 12/22/2003
• Status: Active Grant

• Current Assignee: Noiseout, Inc.
• Original Assignee: Noiseout, Inc.
• Inventors: Schnitta, Bonnie S.
• Primary Examiner(s): San Martin, Edgardo
• Application Number:
  US15/132,089
• Publication Number:
  US 20160232885A1
• Time in Patent Office: 1,317 Days
• Field of Search: 181210, 181200, 181201, 181205, 181295, 181224, 181225, 181226, 454184
• CPC Class Codes: B32B 1/00 Layered products having a non-planar shape
• CPC Class Codes: B32B 15/04 comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a bituminous or tarry layer B32B11/08; next to a water-setting substance layer B32B13/06; next to a glass layer B32B17/061; next to a cellulosic plastic layer B32B23/042
• CPC Class Codes: B32B 15/14 next to a fibrous or filamentary layer
• CPC Class Codes: B32B 2250/40 Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA
• CPC Class Codes: B32B 2262/101 Glass fibres
• CPC Class Codes: B32B 2307/102 Insulating
• CPC Class Codes: B32B 2419/00 Buildings or parts thereof
• CPC Class Codes: B32B 27/06 as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a layer of a particular substance B32B9/045; next to a bituminous or tarry layer B32B11/046; next to a water setting substance layer B32B13/12; next to a metal layer B32B15/08; next to a glass layer B32B17/10; next to a layer formed of natural mineral fibres or particles B32B19/045; next to a wood layer B32B21/08; next to a cellulosic plastic layer B32B23/08; next to a natural or synthetic rubber layer B32B25/08
• CPC Class Codes: B32B 27/12 next to a fibrous or filamentary layer
• CPC Class Codes: B32B 27/304 comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF
• CPC Class Codes: B32B 5/024 Woven fabric
• CPC Class Codes: B32B 5/24 one layer being a fibrous or filamentary layer
• CPC Class Codes: B32B 7/08 by mechanical means
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: E04B 2/7409 special measures for sound or thermal insulation, including fire protection
• CPC Class Codes: E04B 2/7457 with wallboards attached to the outer faces of the posts, parallel to the partition E04B2/7459 takes precedence
• CPC Class Codes: E04B 9/001 characterised by provisions for heat or sound insulation
• CPC Class Codes: E04B 9/006 with means for hanging lighting fixtures or other appliances to the framework of the ceiling
• CPC Class Codes: E04B 9/02 having means for ventilation or vapour discharge
• CPC Class Codes: F24F 13/24 Means for preventing or suppressing noise
• CPC Class Codes: F24F 2013/242 : Sound-absorbing material
• CPC Class Codes: G10K 11/16 : Methods or devices for protecting against, or for damping, noise or other acoustic waves in general G10K11/36 takes precedence
• CPC Class Codes: G10K 11/168 : Plural layers of different materials, e.g. sandwiches
• CPC Class Codes: H04R 1/2803 : for loudspeaker transducers

Abstract

A rugged noise muffler system is configured to substantially surround sound-emitting openings in a working unit or structure, to absorb sound emitted from the sound-emitting openings. A barrier component, formed as a housing, covers a sound emitting opening to inhibit sound from emanating from the housing, except at an open end of the housing. Each sound emitting opening in the working unit or structure requires a housing positioned over same. The housing includes a hood portion and an elongate portion that includes the open end of the housing. The inner surfaces of the hood portion and an elongate portion are lined with sound absorbing material. The emitted sound first enters the hood portion, is partially absorbed therein and any unabsorbed sound passes into and is substantially absorbed in the elongate portion as the sound travels towards the open end of the housing.

Claims

1. A noise attenuation system, comprising a quasi-enclosure configured to substantially surround at least one pre-existing or previously-planned sound-emitting or sound-transferring opening in a working unit or structure that is positioned in a ceiling, wall or floor of a room or space, and to inhibit a direct acoustic path of sound emitted from or entering into the sound-emitting or sound-transferring opening, from or into the room or space in order that sound detected at or proximate the working unit or structure does not exceed a predetermined sound level, wherein the quasi-enclosure comprises:

a sound absorbing muffler plate that comprises at least one layer of sound absorbing material disposed upon an STC barrier layer;

wherein the quasi-enclosure comprises a substantially planar portion of the sound absorbing muffler plate from which side portions formed with the muffler plate extend vertically such that the quasi-enclosure covers the at least one sound-emitting or sound-transferring opening in the working unit or structure and inhibits sound from emanating from the working unit or structure into and/or out of the room or space;

wherein an aperture is provided in the quasi-enclosure at a predetermined distance from a location of the at least one sound-emitting or sound-transferring opening;

wherein the sound emitted from or entering the sound-emitting or sound-transferring opening travels along the predetermined distance within the quasi-enclosure to or from the aperture, during which the traveling sound is contained within the quasi-enclosure by the STC barrier layer and absorbed by the sound absorbing material based on a wavelength of a common frequency of concern, so that said emitted sound detected outside the working unit or structure is perceivably reduced and does not exceed the predetermined sound level; and

wherein the substantially-planar portion of the sound-absorbing muffler plate is moveable towards and away from the sound-emitting or sound-transferring opening in the ceiling, the wall or the floor.

2. The noise attenuation system of claim 1, wherein the predetermined distance is calculated in consideration of a singular or average frequency of the sound emitted from or entering into the at least one sound-emitting or sound-transferring opening.

3. The noise attenuation system of claim 1, wherein the predetermined distance is calculated in consideration of a loudness of the sound emitted from or entering into the at least one sound-emitting or sound-transferring opening.

4. The noise attenuation system of claim 1, wherein the noise absorbing muffler plate includes at least one sound absorbing layer on opposing sides of the STC barrier layer.

5. The noise attenuation system of claim 1, wherein the predetermined distance is calculated in consideration of a sound transmission class (STC) of the barrier layer, a noise reduction coefficient (NRC) rating of the sound absorbing material, or both.

6. The noise attenuation system of claim 1, wherein the working unit or structure is a packaged terminal air conditioning (PTAC) unit, wherein the quasi-enclosure substantially surrounds the PTAC unit but for the aperture and wherein the aperture is arranged at a predetermined distance from an intake opening, an exhaust opening or both in the PTAC unit, while not compromising the required airflow of the intake and exhaust.

7. The noise attenuation system of claim 1, wherein the working unit or structure is an air conditioning (AC) unit, wherein the quasi-enclosure substantially surrounds the AC unit on an inside portion of the AC unit but for the aperture and wherein the aperture is arranged at a predetermined distance from an exhaust opening of AC unit.

10. The noise attenuation system of claim 1, further comprising movable attachment means disposed on the substantially planar portion of the sound absorbing muffler plate that are rotated in a first direction to move the substantially parallel planar portion of the muffler plate towards the opening and are rotated in a second direction to move the substantially parallel planar portion of the muffler plate away from the opening.

8. A noise attenuation system, comprising a quasi-enclosure configured to substantially surround at least one pre-existing or previously-planned sound-emitting or sound-transferring opening in a door to a volume in which noise-generating mechanical equipment is positioned, and to inhibit a direct acoustic path of sound emitted from the sound-emitting or sound-transferring opening in the door, into a room or space in order that sound detected in the room or space proximate the door does not exceed a predetermined sound level for the room or space, wherein the quasi-enclosure comprises:

a sound absorbing muffler plate that comprises at least one layer of sound absorbing material disposed upon an STC barrier layer;

wherein the quasi-enclosure comprises a substantially planar portion of the sound absorbing muffler plate from which side portions formed with the muffler plate extend vertically such that the quasi-enclosure covers the at least one sound-emitting or sound-transferring opening in the door and inhibits sound emitted from the noise generating mechanical equipment from emanating from the volume into the room or space;

wherein an aperture is provided in the quasi-enclosure at a predetermined distance from a location of the at least one sound-emitting or sound-transferring opening in the door;

wherein the sound emitted from or entering the sound-emitting or sound-transferring opening travels along the predetermined distance within the quasi-enclosure to or from the aperture, during which the travelling sound is contained within the quasi-enclosure by the STC barrier layer and absorbed by the sound absorbing material, based on a wavelength of a common frequency of concern, so that said emitted sound detected outside the volume does not exceed the predetermined level sound; and

wherein the substantially-planar portion of the sound-absorbing muffler plate is moveable towards and away from the sound-emitting or sound-transferring opening in the door.

11. The noise attenuation system of claim 8, further comprising movable attachment means disposed on the substantially planar portion of the sound absorbing muffler plate that are rotated in a first direction to move the substantially parallel planar portion of the muffler plate towards the opening and are rotated in a second direction to move the substantially parallel planar portion of the muffler plate away from the opening.

9. A noise attenuation system, comprising a quasi-enclosure configured to substantially surround at least one pre-existing or previously-planned sound-emitting or sound-transferring opening in a HVAC grill on a floor, attached to a duct under the floor, to inhibit a direct acoustic path of sound emitted from or entering into the sound-emitting or sound-transferring opening, from or into the HVAC grill and duct in order that sound detected in a room or space proximate the HVAC grill does not exceed a predetermined level, wherein the quasi-enclosure comprises:

a sound absorbing muffler plate that comprises at least one layer of sound absorbing material disposed upon an STC barrier layer;

wherein the quasi-enclosure comprises a substantially planar portion of the sound absorbing muffler plate from which side portions formed with the muffler plate extend vertically such that the quasi-enclosure covers the at least one sound-emitting or sound-transferring opening in the HVAC grill on the floor and inhibits sound from emanating from or into the HVAC grill on a floor into the room or space;

wherein an aperture is provided in the quasi-enclosure at a predetermined distance from a location of the at least one sound-emitting or sound-transferring opening in the HVAC grill;

wherein the sound emitted from or entering the sound-emitting or sound-transferring opening travels along the predetermined distance within the quasi-enclosure to or from the aperture, during which the traveling sound is contained within the quasi-enclosure by the STC barrier layer and absorbed by the sound-absorbing material, based on a wavelength of a common frequency of concern, so that said emitted sound detected outside the HVAC grill does not exceed the predetermined level sound for the room or space; and

wherein the substantially-planar portion of the sound-absorbing muffler plate is moveable towards and away from the sound-emitting or sound-transferring opening in the HVAC grill on the floor.

12. The noise attenuation system of claim 9, further comprising movable attachment means disposed on the substantially planar portion of the sound absorbing muffler plate that are rotated in a first direction to move the substantially parallel planar portion of the muffler plate towards the opening and are rotated in a second direction to move the substantially parallel planar portion of the muffler plate away from the opening.