Patent ID: 9205912
Filing Date: 2015-12-08
Classification: B64C,F16H,Y02T,Y10T

Abstract:
1. An aerofoil comprising a main aerofoil and an auxiliary aerofoil and where said auxiliary aerofoil can be extended and retracted relative to said main aerofoil to change aerodynamic characteristics of the aerofoil; a compound motion inducing and supporting structure connected between the main aerofoil and the auxiliary aerofoil to permit support and extension and retraction therebetween; said structure comprising at least two arm assemblies each assembly comprising a first swing arm and a second swing arm, said first swing arm and said second swing arm being swingingly connected with each other at respective one ends by a first hinge connection located therebetween; and wherein a second hinge connection is provided at the opposite end of said first swing arm and connected with said main aerofoil, and wherein a third hinge connection is provided at the opposite end of said second swing arm and connected with said auxiliary aerofoil; wherein swing axes of the second hinge connection and third hinge connection are inclined relative to the first hinge connection; each of at least two arm assemblies being mounted to the respective main aerofoil and auxiliary aerofoil in spaced apart relationship; said first swing arm and said second swing arm being mounted to permit swinging about all swing axes and a compound motion to be imparted to the auxiliary aerofoil to cause swing movement of the arms to an extended or retracted condition, and so the swing axis of the second hinge connection and the third hinge connection of each arm assembly trace a path where there will be a respective common plane intersecting therewith at all swing movement positions; wherein in the retracted condition said structure is contained within the profile of the aerofoil; and wherein the aerofoil further comprises respective mechanisms operatively connected to the first arms at or adjacent the first hinge connections to constrain the first arms and the second arms to swing about the respective first hinge connections with mirror image displacements relative to each other during swinging between retracted and extended swing conditions.