US3374856A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flexible sound attenuating duct with foamed plastic lining
Assignee: Garrett Corp
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Filing: 1966-09-09
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Granted: 1968-03-26
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Expires: 1986-09-09
Abstract
No abstract record available.
Inventors
- 👤 Leslie S Wirt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:42
CPC Classifications
F; F24; F24F; F24F13/00; F24F13/24; F02; F02K; F02K1/00; F02K1/78; F02K1/82; F02K1/827; F16; F16L; F16L11/00; F16L11/04; F16L11/11; F16L11/118; F16L9/00; F16L9/21
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
78 words
A FLEXIBLE SOUND-ATTENUATING DUCT COMPRISING: (A) A FLEXIBLE TUBULAR CASING; AND (B) A LINER IN SAID CASING, SAID LINER BEING COMPOSED OF A SOUND-DAMPING MATERIAL WITH A THROUGH-FLOW RESISTANCE OF THE SAME ORDER OF MAGNITUDE AS THE SPECIFIC ACOUSTIC IMPEDANCE OF THE FLUID TO BE CARRIED BY THE DUCT, SAID MATERIAL HAVING THE CHARACTERISTIC BEING EXTENSIBLE IN A DIRECTION PARALLEL TO THE AXIS OF THE CASING WHEN SUBJECTED TO TENSION AND RETRACTABLE UPON THE RELEASE OF SUCH TENSION.
Claim 2
Dependent Claim
78 words
A FLEXIBLE SOUND-ATTENUATING DUCT COMPRISING: (A) A FLEXIBLE TUBULAR CASING; AND (B) A LINER IN SAID CASING, SAID LINER BEING COMPOSED OF A SOUND-DAMPING MATERIAL WITH A THROUGH-FLOW RESISTANCE OF THE SAME ORDER OF MAGNITUDE AS THE SPECIFIC ACOUSTIC IMPEDANCE OF THE FLUID TO BE CARRIED BY THE DUCT, SAID MATERIAL HAVING THE CHARACTERISTIC BEING EXTENSIBLE IN A DIRECTION PARALLEL TO THE AXIS OF THE CASING WHEN SUBJECTED TO TENSION AND RETRACTABLE UPON THE RELEASE OF SUCH TENSION.
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) | 1971-03-26 | 1971-09-25 | 1972-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-03-26 | 1975-09-25 | 1976-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-03-26 | 1979-09-25 | 1980-03-26 | $7700.00 | Window Closed / Lapsed |