US3729957A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fan
Assignee: UK Secretary of State for Defence
•
Filing: 1971-12-21
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Granted: 1973-05-01
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Expires: 1991-12-21
Abstract
Abstract A fan comprises first and second rotor stages driven through a differential gear. The first stage is driven from the sun gear of the differential while the second stage is driven from the annulus gear of the differential. The planet carrier is driven from drive means. The invention is particularly applicable to gas turbine engines in which case the first stage of the fan may comprise a hub compressor and the drive means may comprise a gas turbine.
Inventors
- 👤 J Petrie
- 👤 K Bracey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:16
CPC Classifications
F; F04; F04D; F04D19/00; F04D19/02; F04D19/026; F01; F01D; F01D5/00; F01D5/02; F01D5/022; F02; F02C; F02C7/00; F02C7/04; F02K; F02K3/00; F02K3/02; F02K3/04; F02K3/06; F04D25/00; F04D25/02; F04D25/028; Y; Y02; Y02T; Y02T50/00; Y02T50/60; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19023; Y10T74/19074; Y10T74/19121
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
75 words
A fan comprising a first and a second rotor stage in flow series and a differential gear comprising a sun gear, a plurality of planet gears carried from a planet carrier, and an annulus gear, first connection means by which the first rotor stage is connected to the sun gear, second connection means by which the second rotor stage is drivingly connected to the annulus gear and drive means connected to rotate the planet carrier.
Claim 2
Dependent Claim
75 words
A fan comprising a first and a second rotor stage in flow series and a differential gear comprising a sun gear, a plurality of planet gears carried from a planet carrier, and an annulus gear, first connection means by which the first rotor stage is connected to the sun gear, second connection means by which the second rotor stage is drivingly connected to the annulus gear and drive means connected to rotate the planet carrier.
Claim 3
Dependent Claim
46 words
A fan as claimed in claim 1 and in which said first rotor stage comprises a bladed hub compressor, and the second stage comprises a main bladed rotor stage, the blades of the hub compressor extending over only the central portion of the main rotor stage.
Claim 4
Dependent Claim
21 words
A fan as claimed in claim 2 and in which there is a shroud round the blades of the hub compressor.
Claim 5
Dependent Claim
29 words
A fan as claimed in claim 3 and in which the hub compressor shroud is carried from the main rotor stage and extends forwardly to encompass the hub compressor.
Claim 6
Dependent Claim
17 words
A fan as claimed in claim 1 and in which said drive means comprises a gas turbine.
Claim 7
Dependent Claim
25 words
A fan as claimed in claim 5 and in which said fan drive gas turbine is driven by the exhaust gas of a gas generator.
Claim 8
Dependent Claim
19 words
A fan as claimed in claim 6 and in which said gas generator comprises a gas turbine gas generator.
Claim 9
Dependent Claim
44 words
A fan as claimed in claim 7 and in which said gas generator has an air intake, the rotors being mounted coaxially ahead of the intake so that the fan compresses air which provides by-pass air and supercharged inlet air to the gas generator.
Claim 10
Dependent Claim
20 words
A fan as claimed in claim 8 and in which said gas turbine gas generator comprises a multi-shaft gas generator.
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) | 1976-04-30 | 1976-10-30 | 1977-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-30 | 1980-10-30 | 1981-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-30 | 1984-10-30 | 1985-05-01 | $7700.00 | Window Closed / Lapsed |