Upper surface louvers for lift fans
AssigneeAurora Flight Sciences Corporation, a subsidiary of The Boeing Company
InventorRobert William Parks
Life of this patent
Estimating the term…
Abstract
A fan apparatus is disclosed, including a duct having an inlet opening, a fan mounted in the duct, and a plurality of louver devices positioned at the inlet opening. Each louver device has an open position and a closed position, and adjacent louver devices define a plurality of airflow channels. Each airflow channel has a curvature profile that changes as the louver devices move between open and closed positions.
Claims19
A fan apparatus, comprising:
- a duct having an inlet opening,
- a fan mounted in the duct, and
- a plurality of louver devices positioned at the inlet opening, each louver device having an open position and a closed position, wherein each louver device includes a moveable louver portion rotatable relative to the inlet opening and a control horn fixed to the moveable louver portion, and
- a linkage bar, each control horn being rotatable connected to the linkage bar,
- wherein linear motion of the linkage bar is translated to rotation of the movable louver portions by the control horns, to transition the plurality of louver devices between the open and closed positions, and
- wherein a shape of the control horn varies across the plurality of louver devices, and the angular range of rotation of each moveable louver portion varies between louver devices depending on the shape of the corresponding control horn.
An aircraft, comprising:
- a lift fan mounted in a duct,
- an airfoil structure containing the lift fan and having an upper airfoil surface including a lift fan intake cover having a plurality of louver devices configured to move between an open position and a closed position when the aircraft transitions from a hover mode to a horizontal flight mode,
- wherein:
- a moveable portion of each louver device has an airfoil shape, the airfoil shape varying between louver devices along a longitudinal axis of the duct,
- the longitudinal axis coincides with a relative wind direction when the aircraft is in the horizontal flight mode,
- the plurality of louver devices is moved between the open position and the closed position by a single actuator,
- the actuator is connected to a linkage bar, and the linkage bar is pivotably connected to each louver device,
- the linkage bar is connected to a control horn of each louver device,
- each control horn is fixed to the corresponding moveable louver portion,
- a shape of the control horn varies across the plurality of louver devices,
- the angular range of rotational movement between the open position and the closed position of each louver device depends on the shape of the respective control horn, and
- each moveable louver portion has a greater angular range of rotational movement between the open position and the closed position compared to upstream moveable louver portions.
A method of controlling airflow into a lift fan on an aircraft during a transition phase between a hover mode and a horizontal flight mode, comprising:
- using a plurality of louver devices extending over a lift fan of an airfoil surface to direct airflow, and
- rotating a distal portion of each louver device between open and closed positions, including rotating each distal portion through a different angular range of rotation by translating linear motion of a linkage bar to rotational motion with a control horn of each louver device,
- wherein a shape of the control horn varies between louver devices along the fore-to-aft direction of the aircraft, and the angular range and rate of rotation of each distal portion varies between louver devices depending on the shape of the corresponding control horn.
Dependencies are inferred from the claim text.