Sound attenuating device using an embedded layer for acoustical tuning

• US 8,418,806 B1
• Filed: 01/13/2012
• Issued: 04/16/2013
• Est. Priority Date: 01/13/2012
• Status: Expired due to Fees

• Current Assignee: Janesville, LLC (Jason Industries, Inc.)
• Original Assignee: Janesville Acoustics, A Unit Of Jason Incorporated
• Inventors: Wyerman, Barry, Sargent, Michael, Zupan, Chuck
• Primary Examiner(s): Phillips, Forrest M
• Application Number:
  US13/350,075
• Time in Patent Office: 459 Days
• Field of Search: 181/290, 181/284, 521/44, 521/45
• US Class Current: 181/290
• CPC Class Codes: B32B 2262/0215 Thermoplastic elastomer fibers
• CPC Class Codes: B32B 2307/10 having particular acoustical properties
• CPC Class Codes: B32B 2451/00 Decorative or ornamental articles
• CPC Class Codes: B32B 2605/003 Interior finishings
• CPC Class Codes: B32B 3/266 characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12
• CPC Class Codes: B32B 5/06 characterised by a fibrous or filamentary layer mechanically connected, e.g. by needling to another layer, e.g. of fibres, of paper
• CPC Class Codes: B32B 5/08 the fibres or filaments of a layer being of different substances , e.g. conjugate fibres, mixture of different fibres
• CPC Class Codes: B32B 5/26 another layer next to it also being fibrous or filamentary relative arrangement of fibres or filaments of different layers B32B5/12
• CPC Class Codes: B60R 13/08 Insulating elements, e.g. for sound insulation sound insulating linings for trains B61D17/185; drivers' cabs for load-carrying vehicles insulated against vibrations or noise B62D33/0604; thermal or acoustic insulation of engines F02B77/11; damping of sounds using compensation by electro-acoustic methods G10K11/178
• CPC Class Codes: G10K 11/002 Devices for damping, suppressing, obstructing or conducting sound in acoustic devices G10K1/06 - G10K1/10 take precedence; for electro-mechanical transducers for communication H04R3/002

Abstract

The present invention includes a layered acoustical system for sound attenuation in a vehicle including an external decorative layer; a moldable fiber backer adhesively adhered to a back side of the decorative layer, the moldable fiber backer further including an engineered fiber blend including one or more types of thermoplastic fibers and having a first density; a moldable lofted sound absorber and vibration decoupling layer including being made from another engineered fiber blend including one or more types of thermoplastic fibers and having a second density that is less than the first density of the moldable backer, a top side of the vibration decoupling layer being adhesively adhered to the second side of the moldable fiber backer; and an intermediate layer embedded in a location within the vibration decoupling layer to achieve a balance point between transmission loss and sound absorption.

Claims

1. A layered acoustical system for sound attenuation in a vehicle comprising:

an external decorative layer;

a moldable fiber backer including a first side and a second side, the first side of the moldable fiber backer being adhesively adhered to a back side of the external decorative layer, the moldable fiber backer further including an engineered fiber blend including one or more types of thermoplastic fibers, the moldable fiber backer having a first density;

a moldable lofted sound absorber and vibration decoupling layer including a top side and a bottom side and being made from the same or another engineered fiber blend including one or more types of thermoplastic fibers, the moldable lofted sound absorber and vibration decoupling layer having a second density that is less than the first density of the moldable backer, the top side of the moldable lofted sound absorber and vibration decoupling layer being adhesively adhered to the second side of the moldable fiber backer; and

an intermediate layer embedded in and adhered to a location within the moldable lofted sound absorber and vibration decoupling layer to achieve a balance point between transmission loss and sound absorption.

2. The layered acoustical system of claim 1 wherein the decorative layer is a tufted carpet or a needled non-woven carpet.

3. The layered acoustical system of claim 1 wherein the intermediate layer is an acoustical control layer including a perforated membrane or film, an impermeable membrane, or an airflow resistance layer with preferred air flow control properties.

4. The layered acoustical system of claim 1 wherein the intermediate layer is a perforated film layer made of polyamide and polyethylene and having an unmolded thickness of approximately 0.5 mm, a plurality of approximately 380μ

diameter substantially circular perforations, a hole density of approximately 30 holes/in², and an airflow resistance of approximately 900 Rayls.

5. The layered acoustical system of claim 1 wherein the moldable fiber backer has a surface density of approximately 807 gsm, a thickness of approximately 3 mm, and an airflow resistance of approximately 400 Rayls.

6. The layered acoustical system of claim 1 wherein the moldable lofted sound absorber and vibration decoupling layer has a surface density of approximately 1610 gsm, a thickness in the range of approximately 3 mm to approximately 30 mm, and an airflow resistance of approximately 490 Rayls at 30 mm.

7. The layered acoustical system of claim 1 wherein the external, non-tufted decorative layer is a nonwoven carpet with a thickness of approximately 5 mm, and an airflow resistance of approximately 80 Rayls.

8. The layered acoustical system of claim 1 wherein the location of the perforated film layer in the moldable lofted sound absorber and vibration decoupling layer is at a level about ½

to ⅓

the thickness of the moldable lofted sound absorber and vibration decoupling layer away from the top side of the moldable lofted sound absorber and vibration decoupling layer.

9. The layered acoustical system of claim 1 wherein the intermediate layer is a perforated film layer that comprises at least one layer.

10. The layered acoustical system of claim 1 further comprising a second perforated film layer embedded in and adhered to a location within the moldable backer, the layered acoustical system still constructed to achieve a new balance point between transmission loss and sound absorption.

11. The layered acoustical system of claim 1 wherein the intermediate layer is an air flow resistance layer comprising:

a third fiber blend having a density of approximately 90 gsm, a thickness of approximately 0.3 mm, and an airflow resistance of approximately 2000 Rayls.

12. The layered acoustical system of claim 3 wherein the location of the air flow resistance layer in the moldable lofted sound absorber and vibration decoupling layer is at a level about ⅓

the thickness of the moldable lofted sound absorber and vibration decoupling layer away from the top side of the moldable lofted sound absorber and vibration decoupling layer.

13. The layered acoustical system of claim 1 further comprising an air flow resistance layer embedded in and adhered to a location within the moldable backer, the layered acoustical system still constructed to achieve a new balance point between transmission loss and sound absorption.

14. The layered acoustical system of claim 1 further comprising a second air flow resistance layer embedded in and adhered to a location within the moldable backer, the layered acoustical system constructed to achieve a new balance point between transmission loss and sound absorption.

15. The layered acoustical system of claim 1 further comprising an impermeable membrane layer embedded in and adhered to a location within the moldable backer, the layered acoustical system still constructed to achieve a new balance point between transmission loss and sound absorption.

16. A layered acoustical system for sound attenuation in a vehicle comprising:

a moldable fiber cap layer including a first side and a second side, the first side of the moldable fiber cap layer being uncovered, the moldable fiber cap layer further including an engineered fiber blend including one or more types of thermoplastic fibers, the moldable fiber cap layer having a first density;

a moldable lofted sound absorber and vibration decoupling layer including a top side and a bottom side and being made from another engineered fiber blend including one or more types of thermoplastic fibers, the moldable lofted sound absorber and vibration decoupling layer having a second density that is less than the first density of the moldable fiber cap layer, the top side of the moldable lofted sound absorber and vibration decoupling layer being adhesively adhered to the second side of the moldable fiber cap layer; and

an intermediate layer embedded in and adhered to a location within a single layer of the layered acoustical system to achieve a balance point between transmission loss and sound absorption.

17. The layered acoustical system of claim 16 wherein the location of the perforated film layer is in the moldable lofted sound absorber and vibration decoupling layer.

18. The layered acoustical system of claim 17 wherein the location of the perforated film layer in the moldable lofted sound absorber and vibration decoupling layer is at a level about ½

to ⅓

the thickness of the moldable lofted sound absorber and vibration decoupling layer away from the top side of the moldable lofted sound absorber and vibration decoupling layer.

19. The layered acoustical system of claim 16 wherein the location of the perforated film layer is in the moldable fiber cap layer.

20. The layered acoustical system of claim 16 wherein the embedded intermediate layer is a perforated membrane or film, an impermeable membrane, or an acoustical control layer with preferred air flow control properties.

21. A layered acoustical system for sound attenuation in a vehicle comprising:

an external decorative layer;

a moldable fiber backer including a first side and a second side, the first side of the moldable fiber backer being adhesively adhered to a back side of the external, non-tufted and un-backed decorative layer, the moldable fiber backer further including an engineered fiber blend including one or more types of thermoplastic fibers, the moldable fiber backer having a thickness of about 3 mm and a density of about 807 gsm;

a moldable lofted sound absorber and vibration decoupling layer including a top side and a bottom side and being made from another engineered fiber blend including one or more types of thermoplastic fibers, the moldable lofted sound absorber and vibration decoupling layer having a thickness in the range of from 3 to 30 mm and a density of about 1610 gsm, the top side of the moldable lofted sound absorber and vibration decoupling layer being adhesively adhered to the second side of the moldable fiber backer; and

a perforated film layer including a heat activated adhesive on opposite sides of the perforated film layer, the perforated layer having a thickness of about 0.5 mm, a plurality of perforations each having a diameter of about 380μ and

a hole density of about 30 holes/in², and an airflow resistance of approximately 900 Rayls, the perforated layer being embedded in and adhered to a location within the moldable lofted sound absorber and vibration decoupling layer to achieve a balance point between transmission loss and sound absorption.

22. The layered acoustical system of claim 21 wherein the location of the perforated film layer in the moldable lofted sound absorber and vibration decoupling layer is at a level about ½

to ⅓

the thickness of the moldable lofted sound absorber and vibration decoupling layer away from the top side of the moldable lofted sound absorber and vibration decoupling layer.