US3831376A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thrust reverser
Assignee: Leonardo SpA
•
Filing: 1973-02-05
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Granted: 1974-08-27
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Expires: 1993-02-05
Abstract
Abstract A fan air thrust reverser for a high by-pass ratio turbofan aircraft engine wherein the fan air exit duct wall is constructed as a thin wall or single thickness panel to achieve a low boattail angle nacelle and the reverser assembly comprises a circumferential series of plug type doors inwardly retractable from the duct wall for forming transverse openings through which the exhaust flow can be directed for thrust reversal, provided that thrust reverser cascade panels, normally stowed upstream of the transverse openings, are translated aft into a position over the transverse openings; and the plug type doors are further actuated to rotate inwardly for flow blockage from their trail or idling position parallel to the fan airstream. Safety features being in first translating the blocker door through a parallelogram linkage arrangement to a fan flow trail position, which, if accidentally happened at high speed, would not reverse thrust without further application of signal and power. Also, at high speed (or any speed where reversing was not desired in flight), the cascades must be positioned over the openings or only lateral thrust would result all around the nacelle. The reverser system is thus armed by first placing the cascades over the door openings during take off and just prior to touchdownlanding.
Inventors
- 👤 J Moorehead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:58
CPC Classifications
F; F02; F02K; F02K1/00; F02K1/54; F02K1/64; F02K1/70; F02K1/78; F02K1/82; F02K1/827
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
161 words
In combination with a jet engine fluid flow duct, a forward thrust flow modulating apparatus for a jet engine comprising: a panel forming an inner plug-type panel of the duct wall and being retained in pressure sealing engagement by differential pressure between the engine thrust fluid flow within the duct and the external atmospheric pressure on the outside of the duct wall; linkage means for deploying the panel inwardly from the wall of the duct to an intermediate position within the duct so as to aerodynamically trail the panel in the engine thrust fluid flow; said panel exposing a transverse opening in the duct wall when deployed to the intermediate Position; actuator means for positioning the panel from the intermediate trail position to a position so as to deflect the fluid flow to exit through the transverse opening; whereby the forward thrust flow is modulated by diverting the flow outwardly and thus decreasing the forward thrust vector of the jet engine.
Claim 2
Dependent Claim
161 words
In combination with a jet engine fluid flow duct, a forward thrust flow modulating apparatus for a jet engine comprising: a panel forming an inner plug-type panel of the duct wall and being retained in pressure sealing engagement by differential pressure between the engine thrust fluid flow within the duct and the external atmospheric pressure on the outside of the duct wall; linkage means for deploying the panel inwardly from the wall of the duct to an intermediate position within the duct so as to aerodynamically trail the panel in the engine thrust fluid flow; said panel exposing a transverse opening in the duct wall when deployed to the intermediate Position; actuator means for positioning the panel from the intermediate trail position to a position so as to deflect the fluid flow to exit through the transverse opening; whereby the forward thrust flow is modulated by diverting the flow outwardly and thus decreasing the forward thrust vector of the jet engine.
Claim 3
Dependent Claim
45 words
The apparatus as set forth in claim 1, wherein said linkage means comprises a parallelogram linkage arrangement for lateral displacement of the panel inwardly from the wall of the duct and parallel to the fluid flow within the duct when deployed to the intermediate position.
Claim 4
Dependent Claim
66 words
The apparatus as set forth in claim 1, wherein said panel has a scoop like leading edge which immediately picks up fluid flow within the duct as it is cracked open for displacement inwardly and simultaneously opens up a passageway through the wall of the duct which has a cross-sectional flow area substantially equivalent to the area of fluid flow picked up by the protruding scoop.
Claim 5
Dependent Claim
130 words
In combination with a high by-pass ratio turbofan engine, a fan thrust airflow modulating apparatus comprising: a duct for the fan thrust airflow; a panel forming an inner plug-type panel of the duct wall; linkage means for deploying the panel inwardly from the wall of the duct to an intermediate position within the duct so as to aerodynamically trail the panel in the fan thrust airflow; said panel exposing a transverse opening in the duct wall when deployed to the intermediate position; actuator means for positioning the panel from the intermediate trail position to a position so as to deflect the fan airflow outwardly through the transverse opening whereby the fan thrust airflow is modulated by diverting the flow outwardly and thus decreasing the magnitude of the forward thrust vector.
Claim 6
Dependent Claim
130 words
In combination with a high by-pass ratio turbofan engine, a fan thrust airflow modulating apparatus comprising: a duct for the fan thrust airflow; a panel forming an inner plug-type panel of the duct wall; linkage means for deploying the panel inwardly from the wall of the duct to an intermediate position within the duct so as to aerodynamically trail the panel in the fan thrust airflow; said panel exposing a transverse opening in the duct wall when deployed to the intermediate position; actuator means for positioning the panel from the intermediate trail position to a position so as to deflect the fan airflow outwardly through the transverse opening whereby the fan thrust airflow is modulated by diverting the flow outwardly and thus decreasing the magnitude of the forward thrust vector.
Claim 7
Dependent Claim
45 words
The apparatus as set forth in claim 4, wherein said linkage means comprises a parallelogram linkage arrangement for lateral displacement of the panel inwardly from the wall of the duct and parallel to the fluid flow within the duct when deployed to the intermediate position.
Claim 8
Dependent Claim
66 words
The apparatus as set forth in claim 4, wherein said panel has a scoop like leading edge which immediately picks up fluid flow within the duct as it is cracked open for displacement inwardly and simultaneously opens up a passageway through the wall of the duct which has a cross-sectional flow area substantially equivalent to the area of fluid flow picked up by the protruding scoop.
Claim 9
Dependent Claim
161 words
A fan airflow thrust reversing apparatus for a high by-pass ratio turbofan engine, comprising: a duct for the fan thrust airflow; a panel forming an inner plug-type closure in the duct wall; linkage means for deploying the panel inwardly from the wall of the duct to an intermediate position within the duct so as to aerodynamically trail the panel in the fan thrust airflow; said panel exposing a transverse opening in the duct wall when deployed to said intermediate position; vane elements stowed in the duct wall upstream of the transverse opening for turning the flow directed therethrough to produce a forwardly inclined thrust vector; means for translating the vane elements from their stowed position to an extended position adjacent to the transverse opening; means for positioning the panel from the intermediate trail position to a position so as to deflect the fan airflow outwardly through both the transverse opening and the vane elements whereby the fan thrust airflow is reversed.
Claim 10
Dependent Claim
161 words
A fan airflow thrust reversing apparatus for a high by-pass ratio turbofan engine, comprising: a duct for the fan thrust airflow; a panel forming an inner plug-type closure in the duct wall; linkage means for deploying the panel inwardly from the wall of the duct to an intermediate position within the duct so as to aerodynamically trail the panel in the fan thrust airflow; said panel exposing a transverse opening in the duct wall when deployed to said intermediate position; vane elements stowed in the duct wall upstream of the transverse opening for turning the flow directed therethrough to produce a forwardly inclined thrust vector; means for translating the vane elements from their stowed position to an extended position adjacent to the transverse opening; means for positioning the panel from the intermediate trail position to a position so as to deflect the fan airflow outwardly through both the transverse opening and the vane elements whereby the fan thrust airflow is reversed.
Claim 11
Dependent Claim
314 words
In combination with a high by-pass ratio turbofan engine, a sound suppressor and fan airflow thrust reversing apparatus, comprising: a primary duct for the engine turbine exhaust flow; a secondary duct in laterally spaced relation to the primary duct and having a greater cross-sectional flow area for the fan thrust airflow; a panel forming an inner plug-type closure in the secondary duct wall between the fan airflow within the secondary duct and the external atmospheric pressure on the outside of the secondary duct wall; linkage means for deploying the panel inwardly fRom the wall of the secondary duct to an intermediate position within the secondary duct so as to aerodynamically trail the panel in the fan thrust airflow; said panel exposing a transverse opening in the secondary duct wall when deployed to said intermediate position; vane elements stowed in the secondary duct wall upstream of the transverse opening for turning the flow directed therethrough to produce a forwardly inclined thrust vector; means for translating the vane elements from their stowed position to an extended position adjacent to the transverse opening; means for positioning the panel from the intermediate trail position to a position so as to deflect the fan airflow outwardly through both the transverse opening and the vane elements for reversing the fan thrust airflow; acoustic panels positioned within the secondary duct downstream of the fan blade section and upstream of the panel for attenuating the noise emitted by the fan blading; said primary duct turbine exhaust flow being merged into the larger volume of the secondary duct at a position downstream of the panel when it is in the deflected fan airflow position; whereby the forward thrust due to the engine primary flow is effectively decreased by the rapid expansion of the primary flow in the larger volume and the subsequently reduced velocity attenuates the noise emitted by the engine turbine section.
Claim 12
Dependent Claim
314 words
In combination with a high by-pass ratio turbofan engine, a sound suppressor and fan airflow thrust reversing apparatus, comprising: a primary duct for the engine turbine exhaust flow; a secondary duct in laterally spaced relation to the primary duct and having a greater cross-sectional flow area for the fan thrust airflow; a panel forming an inner plug-type closure in the secondary duct wall between the fan airflow within the secondary duct and the external atmospheric pressure on the outside of the secondary duct wall; linkage means for deploying the panel inwardly fRom the wall of the secondary duct to an intermediate position within the secondary duct so as to aerodynamically trail the panel in the fan thrust airflow; said panel exposing a transverse opening in the secondary duct wall when deployed to said intermediate position; vane elements stowed in the secondary duct wall upstream of the transverse opening for turning the flow directed therethrough to produce a forwardly inclined thrust vector; means for translating the vane elements from their stowed position to an extended position adjacent to the transverse opening; means for positioning the panel from the intermediate trail position to a position so as to deflect the fan airflow outwardly through both the transverse opening and the vane elements for reversing the fan thrust airflow; acoustic panels positioned within the secondary duct downstream of the fan blade section and upstream of the panel for attenuating the noise emitted by the fan blading; said primary duct turbine exhaust flow being merged into the larger volume of the secondary duct at a position downstream of the panel when it is in the deflected fan airflow position; whereby the forward thrust due to the engine primary flow is effectively decreased by the rapid expansion of the primary flow in the larger volume and the subsequently reduced velocity attenuates the noise emitted by the engine turbine section.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-08-26 | 1978-02-25 | 1978-08-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-26 | 1982-02-25 | 1982-08-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-26 | 1986-02-25 | 1986-08-27 | $7700.00 | Window Closed / Lapsed |