Patent US3081160A successfully refreshed from Google Patents.
Patent US3640357A successfully refreshed from Google Patents.
US3640357A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustic linings
Assignee: Rolls Royce PLC
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Filing: 1971-02-26
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Granted: 1972-02-08
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Expires: 1991-02-26
Abstract
Abstract The invention provides an acoustic lining, suitable for a gas turbine engine, the lining comprising an impervious sheet, a channel layer, a first porous sheet, a honeycomb layer and a second porous sheet, the channel layer being secured to the impervious sheet and the first porous sheet and the honeycomb layer being secured between the first and second porous sheets.
Inventors
- 👤 Anthony George Kitching
- 👤 Mervyn Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 18:27
CPC Classifications
F; F02; F02K; F02K1/00; F02K1/78; F02K1/82; F02K1/827; F01; F01N; F01N1/00; F01N1/24; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24149
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
49 words
An acoustic lining comprising an impervious sheet, a channel layer, a first porous sheet, a honeycomb layer and a second porous sheet, the channel layer being secured to the impervious layer and the first porous sheet and the honeycomb layer being secured between the first and second porous sheets.
Claim 2
Dependent Claim
49 words
An acoustic lining comprising an impervious sheet, a channel layer, a first porous sheet, a honeycomb layer and a second porous sheet, the channel layer being secured to the impervious layer and the first porous sheet and the honeycomb layer being secured between the first and second porous sheets.
Claim 3
Dependent Claim
29 words
An acoustic lining as claimed in claim 1 in which the first porous sheet has perforations which are larger in size than corresponding perforations in the second porous sheet.
Claim 4
Dependent Claim
29 words
An acoustic lining as claimed in claim 2 in which the maximum width of each channel is approximately equal to the width across each cell of the honeycomb layer.
Claim 5
Dependent Claim
18 words
An acoustic lining as claimed in claim 1 in which the channels of the channel layer are interconnected.
Claim 6
Dependent Claim
25 words
An acoustic lining as claimed in claim 4 in which the channels are interconnected by means of slots formed in the walls of adjacent channels.
Claim 7
Dependent Claim
26 words
An acoustic lining as claimed in claim 4 in which the channels are interconnected by forming the walls of the channels so that they are porous.
Claim 8
Dependent Claim
31 words
An acoustic lining as claimed in claim 1 in which the first and second porous sheets are metallic and the channel layer is formed from a glass fiber reinforced composite sheet.
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) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |