US4408679A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sound attenuator
Assignee: Peabody Spunstrand Inc
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Filing: 1981-09-28
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Granted: 1983-10-11
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Expires: 2001-09-28
Abstract
Abstract A sound attenuator for reducing noise and vibration generated by flow of air, particularly air laden with moisture, particulates and corrosive substances. The sound attenuator comprises a tubular housing and a layer of sound attenuating material, such as closed-cell polyurethane foam, removably secured in the interior of the tubular housing. A retaining ring is located at each end portion of the housing and retain the attenuating layer therebetween to avoid substantial longitudinal sliding movement of the attenuating layer by the force of air flowing therethrough. If the attenuating layer becomes abraided by particulates or absorbs an undesirable amount of moisture during use, the sound attenuating layer can be removed and replaced.
Inventors
- 👤 J. Kerry Littrell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:38
CPC Classifications
F; F24; F24F; F24F13/00; F24F13/24; F16; F16L; F16L55/00; F16L55/02; F16L55/033; F16L55/0336
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
293 words
A lightweight, corrosion resistant sound attenuator having replaceable sound attenuating material which may become contaminated, abraided or absorb moisture during use, the attenuator comprising: a tubular housing comprising a lightweight plastic material, having two end portions and having an interior surface; a layer of sound attenuating material having an outer side positioned in abutting relation with said interior surface of the tubular housing, said layer having an interior surface defining an axial flow passage through the housing, said layer being removeable to provide for replacement thereof; a first annular ring inserted in and fixed to the interior surface of said housing at one end portion, said ring having a wall extending inwardly from the interior surface of the housing, said wall having an inward end, said wall retaining said layer against longitudinal sliding movement in one direction, said first ring including an interior transition surface converging from the interior surface of said housing radially and longitudinally inwardly to said inward end of said retaining wall, said first ring including a cyclindrical sleeve extending longitudinally from said inward end of said retaining wall to define a slot between it and said interior surface of said housing for retaining the end of said layer of sound attenuating material, said sleeve providing a smooth transition betwen said ring and the end of said layer; a second annular ring fixed to the interior surface of the housing at the other end portion and having a wall extending inwardly from the interior surface of the housing for retaining said layer against longitudinal sliding movement in an opposite direction; means for retaining said attenuating layer in abutting relation with the interior surface of the housing, said retaining means being removeable to provide for replacement of said sound attenuating layer.
Claim 2
Dependent Claim
293 words
A lightweight, corrosion resistant sound attenuator having replaceable sound attenuating material which may become contaminated, abraided or absorb moisture during use, the attenuator comprising: a tubular housing comprising a lightweight plastic material, having two end portions and having an interior surface; a layer of sound attenuating material having an outer side positioned in abutting relation with said interior surface of the tubular housing, said layer having an interior surface defining an axial flow passage through the housing, said layer being removeable to provide for replacement thereof; a first annular ring inserted in and fixed to the interior surface of said housing at one end portion, said ring having a wall extending inwardly from the interior surface of the housing, said wall having an inward end, said wall retaining said layer against longitudinal sliding movement in one direction, said first ring including an interior transition surface converging from the interior surface of said housing radially and longitudinally inwardly to said inward end of said retaining wall, said first ring including a cyclindrical sleeve extending longitudinally from said inward end of said retaining wall to define a slot between it and said interior surface of said housing for retaining the end of said layer of sound attenuating material, said sleeve providing a smooth transition betwen said ring and the end of said layer; a second annular ring fixed to the interior surface of the housing at the other end portion and having a wall extending inwardly from the interior surface of the housing for retaining said layer against longitudinal sliding movement in an opposite direction; means for retaining said attenuating layer in abutting relation with the interior surface of the housing, said retaining means being removeable to provide for replacement of said sound attenuating layer.
Claim 3
Dependent Claim
47 words
A sound attenuator according to claim 1 wherein said means for retaining said attenuating layer in abutting relation with said interior surface of the housing comprises at least one expanding spring hoop having a surface contacting and urging the interior surface of said attenuating layer radially outwardly.
Claim 4
Dependent Claim
15 words
A sound attenuator according to claim 1 wherein said tubular housing comprises fiberglass reinforced plastic.
Claim 5
Dependent Claim
27 words
A sound attenuator according to claim 1 wherein said housing includes a flange located at at least one end portion of the housing and extending radially outwardly.
Claim 6
Dependent Claim
16 words
A sound attenuator according to claim 1 wherein said sound attenuating layer comprises closed-cell polymeric foam.
Claim 7
Dependent Claim
15 words
A sound attenuator according to claim 5 wherein said polymeric closed-cell foam comprises polyurethane foam.
Claim 8
Dependent Claim
22 words
A sound attenuator layer according to claim 6 wherein said attenuating layer has on the interior surface thereof a polyurethane film facing.
Claim 9
Dependent Claim
27 words
A sound attenuator according to claim 1 and further including means for channelling said air flow outwardly and longitudinally along said interior surface of said attenuating layer.
Claim 10
Dependent Claim
34 words
A sound attenuator according to claim 8 wherein said channelling means comprises a splitting device having a diameter less than the inner diameter of said attenuating layer to define an annularly shaped flow channel.
Claim 11
Dependent Claim
49 words
An attenuator according to claim 1 wherein said second annular ring includes a cylindrical sleeve extending longitudinally from said inward end of said retaining wall to define a slot between it and said interior surface of the housing for retaining the end of said layer of sound attenuating material.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-10 | 1987-04-11 | 1987-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-10 | 1991-04-11 | 1991-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-10 | 1995-04-11 | 1995-10-11 | $7700.00 | Window Closed / Lapsed |