US4156344A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Inlet guide vane bleed system
Assignee: Boeing Co
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Filing: 1976-12-27
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Granted: 1979-05-29
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Expires: 1996-12-27
Abstract
Abstract This invention is an improvement to a turbofan engine intended to reduce fan noise caused by the interaction of the rotor with secondary flow generated by the inlet guide vanes. A portion of the air flowing through the engine is removed from the fan duct from a region between the inlet guide vanes and the rotor and near the outer periphery of the fan duct by a system of bleed ducts. The ducts have one or more openings in the fan casing. The system may also include means for controlling the flow through the bleed ducts and means for injecting high energy flow into the bleed ducts to assist in ejecting the bleed flow.
Inventors
- 👤 Robert D. Cuthbertson
- 👤 Larry A. Schaut
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:37
CPC Classifications
F; F02; F02C; F02C7/00; F02C7/04; F02C7/045; F04; F04D; F04D27/00; F04D27/02; F04D27/0207; F04D27/0215; F04D27/023; F04D29/00; F04D29/40; F04D29/52; F04D29/54; F04D29/541; F04D29/545; F04D29/66; F04D29/68; F04D29/681; F04D29/682
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
129 words
In combination with a gas turbine engine of the type commonly known as a turbofan including an annular nacelle having an inner wall which forms a fan duct for the passage of air through the engine, a rotor having a plurality of radially oriented, circumferentially spaced blades and a set of radially oriented inlet guide vanes disposed within said fan duct forward of said rotor, the improvement comprising: means for removing a portion of said air from said fan duct downstream of said inlet guide vanes but upstream of said rotor, said means including a bleed duct having an opening on said inlet guide vane but upstream of said rotor; and means for injecting high energy flow into said bleed duct to facilitate removal of said portion of air.
Claim 2
Dependent Claim
129 words
In combination with a gas turbine engine of the type commonly known as a turbofan including an annular nacelle having an inner wall which forms a fan duct for the passage of air through the engine, a rotor having a plurality of radially oriented, circumferentially spaced blades and a set of radially oriented inlet guide vanes disposed within said fan duct forward of said rotor, the improvement comprising: means for removing a portion of said air from said fan duct downstream of said inlet guide vanes but upstream of said rotor, said means including a bleed duct having an opening on said inlet guide vane but upstream of said rotor; and means for injecting high energy flow into said bleed duct to facilitate removal of said portion of air.
References Cited (Backward Citations)
US3632223A
Cited
US3730639A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-28 | 1982-11-27 | 1983-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-28 | 1986-11-27 | 1987-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-28 | 1990-11-27 | 1991-05-29 | $7700.00 | Window Closed / Lapsed |