Patent US3842932A successfully refreshed from Google Patents.
US3842932A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sound-trap muffler
Assignee: Individual
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Filing: 1972-11-01
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Granted: 1974-10-22
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Expires: 1992-11-01
Abstract
Abstract Muffler for sound transmitted by low-volume exhausts comprising a structure providing a plurality of aligned cylindrical chambers having acoustic surfaces of alternate large and smaller diameters, and concentric dividers substantially centered in the larger chambers, whereby the area between the periphery of each divider and the adjacent walls of a larger chamber is at least equal to the area of the otherwise open bore through the aligned chambers. Restriction of flow of gas through the muffler is minimized and the diameter of the divider is at least equal to the diameter of the bore, whereby the mean free path for sound waves through the aligned chambers is equal to at least substantially twice the length of the bore to thereby trap and adsorb sound waves transmitted by the air in the aligned chambers.
Inventors
- 👤 S Gibel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:40
CPC Classifications
F; F01; F01N; F01N13/00; F01N13/18; F01N13/1838; F01N13/1844; F01N1/00; F01N1/08; F01N1/10; F01N13/1855; F01N13/1888; F01N13/1894; F01N2310/00; F01N2310/02; F01N2450/00; F01N2450/24; F01N2490/00; F01N2490/18
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
201 words
A muffler for a low-volume exhaust comprising a casing having end closures therefor, each closure having an opening into the interior of said casing and at least one such opening permitting connection to an exhaust outlet, a plurality of adjacent axially concentric ring structures within said casing, said ring structures having alternate larger and smaller inner diameters, the axial thicknesses and inner diameters of said rinG structures defining alternate large and small volume chambers, the crosssectional areas of said chambers being aligned with said casing openings and the cross-sectional area of the smaller chambers being at least as large as the cross-sectional area of either of said casing openings to provide a bore through said muffler, and a partition located within each of the larger chambers and closing off said bore thereat and means to support said partitions so as to provide a passageway around each partition having a total cross-sectional area not less than the crosssectional area of said bore but whereby the mean free path through said muffler is longer than the axial length of said bore through said chambers, said chambers having surface portions of substantially anechoic acoustic material whereby said chambers provide traps for sound waves therewithin.
Claim 2
Dependent Claim
201 words
A muffler for a low-volume exhaust comprising a casing having end closures therefor, each closure having an opening into the interior of said casing and at least one such opening permitting connection to an exhaust outlet, a plurality of adjacent axially concentric ring structures within said casing, said ring structures having alternate larger and smaller inner diameters, the axial thicknesses and inner diameters of said rinG structures defining alternate large and small volume chambers, the crosssectional areas of said chambers being aligned with said casing openings and the cross-sectional area of the smaller chambers being at least as large as the cross-sectional area of either of said casing openings to provide a bore through said muffler, and a partition located within each of the larger chambers and closing off said bore thereat and means to support said partitions so as to provide a passageway around each partition having a total cross-sectional area not less than the crosssectional area of said bore but whereby the mean free path through said muffler is longer than the axial length of said bore through said chambers, said chambers having surface portions of substantially anechoic acoustic material whereby said chambers provide traps for sound waves therewithin.
Claim 3
Dependent Claim
69 words
A muffler as defined in claim 1 in which said chambers are formed by stacked rings of said acoustic material, the axial length of the rings defining the smaller chambers being substantially equal to the diameter of said bore, and at least a pair of rings defining said larger chambers and each having an axial length substantially equal to the axial length of the rings defining adjacent smaller chambers.
Claim 4
Dependent Claim
30 words
A muffler as defined in claim 2, in which the volume of each of said larger chambers is at least six times the volume of one of said smaller chambers.
Claim 5
Dependent Claim
73 words
A muffler as defined in claim 3 in which said partitions are supported within said larger chambers and extend radially beyond the bore openings in said adjacent smaller chambers, the surfaces of each of said partitions being spaced from adjacent surfaces of the larger chamber in which it is supported to provide a passageway around it, each such passageway having a total cross-sectional area not less than the cross-sectional area of said bore.
Claim 6
Dependent Claim
95 words
A muffler as defined in claim 3 in which a perforate tube extending between the openings in said casing fits the bores of said smaller rings, partitions blocking said tube and located within the portions of said tube passing through said larger chambers, the perforations in said tube being substantially evenly distributed therein and providing opening areas on either side of each partition into an adjacent larger chamber, the total area of such opening areas on either side of each of said partitions being at least as large as the cross-sectional area of said tube.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-21 | 1978-04-22 | 1978-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-21 | 1982-04-22 | 1982-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-21 | 1986-04-22 | 1986-10-22 | $7700.00 | Window Closed / Lapsed |