Aeronautics and astronautics – Aircraft structure – Details
Reexamination Certificate
1999-12-29
2001-04-24
Jordan, Charles T. (Department: 3644)
Aeronautics and astronautics
Aircraft structure
Details
C244S129500, C244S054000
Reexamination Certificate
active
06220546
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to aircraft engine cowls and, more particularly, to attachment assemblies that moveably mount the fan cowls of a turbofan engine.
BACKGROUND OF THE INVENTION
Many different types of aircraft are propelled by turbofan engines. It is common for a turbofan engine to be connected to the fuselage or a wing of an aircraft by a pylon. Such a turbofan engine typically includes a nacelle that is a streamline enclosure that contains internal parts of the engine. A nacelle includes an inlet assembly that is positioned at the front of the turbofan engine, extends arcuately around the rotational axis of the engine, and defines an opening through which air is drawn into the engine. The nacelle further includes oppositely oriented right and left fan cowls that are immediately rearward of the inlet assembly and extend arcuately partially around the rotational axis of the engine. The fan cowls cover internal parts of the turbofan engine, such as a fan case and electrical components that control the operation of the engine. The fan cowls are operable to provide access to internal components of the turbofan engine, such as during maintenance of the engine.
Each of the fan cowls includes a horizontally extending top edge that is hinged so each fan cowl can be opened by pivoting the cowl upward about the hinge. It can be difficult to manually open the fan cowls because they must be lifted to facilitate the pivoting about their horizontal top edges. It can be particularly difficult to open the fan cowls of large turbofan engines because the cowls are large, bulky and may be heavy, and for some aircraft the cowls are positioned high above the ground and are therefore difficult to reach. Turbofan engines with heavy fan cowls are often equipped with powered door opening systems that are operative to automatically open the fan cowls. Such powered door opening systems add to the weight of the turbofan engine and thereby the weight of the associated aircraft, which can be disadvantageous. Further, when the above-described fan cowls are open they may catch wind in a manner that adds to the difficulty of opening and closing the cowls. In addition, components of nacelles must be designed to handle wind related loading that occurs when fan cowls of the above-described type are open.
Accordingly there is a need for an aircraft engine, such as a turbofan engine, with cowls, such as fan cowls, that are relatively easy to open and close.
SUMMARY OF THE INVENTION
The present invention solves the above and other problems by providing cowls, such as fan cowls, for a turbofan engine of an aircraft that can be placed in an open configuration by moving the cowls outward and then forward, and placed in a closed configuration by moving the cowls rearward and then inward. As such, the cowls are relatively easy to open and close.
In accordance with one aspect of the present invention, the aircraft engine has opposite front and rear ends, extends in a longitudinal direction between the front and rear ends, and defines a longitudinal axis that extends between the front and rear ends. The aircraft engine includes a reference portion, and each cowl extends arcuately at least partially around the longitudinal axis of the aircraft engine and is operative for covering at least a part of the reference portion while in the closed configuration. Each cowl is movably mounted in relation to the reference portion so that the cowls move both radially away from the longitudinal axis and in the longitudinal direction as the cowls are moved from the closed configuration to the open configuration. Further, the cowls move both in the longitudinal direction and radially toward the longitudinal axis as the cowls are moved from the open configuration to the closed configuration.
In accordance with another aspect of the present invention, the reference portion of the aircraft engine includes an inlet assembly that is positioned at the front of the aircraft engine. The inlet assembly includes an exterior surface that extends arcuately at least partially around the longitudinal axis of the aircraft engine. The cowls are generally rearward of the inlet assembly in the closed configuration. The cowls are movably mounted in relation to the inlet assembly so that the cowls move both radially away from the inlet assembly and forward in the longitudinal direction relative to the inlet assembly as the cowls are moved from the closed configuration to the open configuration, and that movement is reversed as the cowls are moved from the open configuration to the closed configuration.
In accordance with another aspect of the present invention, each cowl is movably mounted in relation to the reference portion of the aircraft engine by a respective pivot assembly that is operative so that the cowls pivot between the closed configuration and the open configuration. A representative pivot assembly for one of the cowls includes upper and lower arms, each of which has opposite first and second ends. The first end of the upper arm is pivotally mounted in relation to the reference portion of the aircraft engine for pivoting about a rotational axis, and the second end of the upper arm is pivotally mounted in relation to the cowl for pivoting about another rotational axis. Likewise, the first end of the lower arm is pivotally mounted in relation to the reference portion of the aircraft engine for pivoting about a rotational axis, and the second end of the lower arm is pivotally mounted in relation to the cowl for pivoting about another rotational axis. The rotational axes of the first end of the upper arm, the second end of the upper arm, the first end of the second arm, and second end of the lower arm generally parallel. The rotational axis of the first end of the lower arm is radially farther from the longitudinal axis than the rotational axis of the first end of the upper arm, and the rotational axes of the first end of the lower arm and the first end of the upper arm are spaced apart from one another in the longitudinal direction. Likewise, the rotational axis of the second end of the lower arm is radially farther from the longitudinal axis than the rotational axis of the second end of the upper arm, and the rotational axes of the second end of the lower arm and the second end of the first arm are spaced apart from one another in the longitudinal direction.
In accordance with another aspect of the present invention, the arms are curved in a manner that enhances the extent to which the second ends of the upper and lower arms are capable of moving forward of the first ends of the upper and lower arms during the open configuration.
Because the cowls are opened by moving them outward and then forward, or the like, and closed by moving them rearward and then inward, or the like, the cowls are advantageously relatively easy to manually open and close.
REFERENCES:
patent: 2763900 (1956-09-01), McAfee et al.
patent: 4044973 (1977-08-01), Moorehead
patent: 4442987 (1984-04-01), Legrand et al.
patent: 4585189 (1986-04-01), Buxton
patent: 4679750 (1987-07-01), Burhans
patent: 4697763 (1987-10-01), Vermilye
patent: 4720065 (1988-01-01), Hamatani
patent: 5035379 (1991-07-01), Hersen et al.
patent: 5203525 (1993-04-01), Remlaoui
patent: 5350136 (1994-09-01), Prosser et al.
patent: 5372338 (1994-12-01), Carlin et al.
patent: 5497961 (1996-03-01), Newton
patent: 5673874 (1997-10-01), Howard
patent: 5941061 (1999-08-01), Sherry et al.
patent: 6032901 (2000-03-01), Carimali et al.
Klamka Andrew
Parham Dean Leon
Alston & Bird LLP
Best Christian M.
Jordan Charles T.
The Boeing Company
LandOfFree
Aircraft engine and associated aircraft engine cowl does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Aircraft engine and associated aircraft engine cowl, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Aircraft engine and associated aircraft engine cowl will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2527865