Method and apparatus for deploying an auxiliary lift foil
View Patent ↗Apparatus connecting an auxiliary lift foil, such as a flap or slat, to a main lift element. The apparatus comprises: a drop link pivotally coupled to the main lift element by a first hinge and to the auxiliary lift foil by a second hinge, wherein the drop link is substantially rigid between the first and second hinges; and a linkage mechanism pivotally coupled to the auxiliary lift foil by a third hinge which is spaced from the second hinge, and to the main lift element by as fourth hinge. The linkage mechanism comprises: a second link pivotally coupled to the airfoil by the third hinge; a third link pivotally coupled to the drop link and/or the auxiliary lift foil by a fifth hinge; and a lever pivotally coupled to the main lift element by a fourth hinge, to the second link by a sixth hinge, and to the third link by a seventh hinge. The drop link is rotated clockwise about the first hinge. In a first phase the auxiliary lift foil is rotated anticlockwise about the second hinge relative to the drop link, and in a second phase it is rotated clockwise about the second hinge relative to the drop link.
1. Apparatus connecting an auxiliary lift foil to a main lift element, the apparatus comprising:
a drop link pivotally coupled to the main lift element by a first hinge, said first hinge is fixed relative to the main lift element, and to the auxiliary lift foil by a second hinge, wherein the drop link is substantially rigid the entire distance between the first and second hinges; and
a linkage mechanism pivotally coupled to the auxiliary lift foil by a third hinge which is spaced from the second hinge, and to the main lift element by a fourth hinge, said fourth hinge is fixed relative to said main lift element.
2. The apparatus of claim 1 wherein the linkage mechanism is pivotally coupled to the drop link and/or to the auxiliary lift foil by a fifth hinge.
3. The apparatus of claim 2 wherein the linkage mechanism comprises:
a second link pivotally coupled to the auxiliary lift foil by the third hinge;
a third link pivotally coupled to the drop link and/or the auxiliary lift foil by the fifth hinge; and
a lever pivotally coupled to the main lift element by the fourth hinge, to the second link by a sixth hinge, and to the third link by a seventh hinge.
4. The apparatus of claim 2 wherein the fifth hinge is coaxial with the second hinge.
5. The apparatus of claim 3 further comprising a rotary actuator configured to rotate the lever about the fourth hinge.
6. The apparatus of claim 3 wherein the distance between the seventh hinge and the fourth hinge is greater than the distance between the seventh hinge and the sixth hinge.
7. The apparatus of claim 3 wherein the second link is substantially rigid between the third and sixth hinges.
8. The apparatus of claim 3 wherein the third link is substantially rigid between the fifth and seventh hinges.
9. The apparatus of claim 3 wherein the lever is substantially rigid between the fourth, sixth and seventh hinges.
10. A lift foil comprising a main lift element; an auxiliary lift foil;
and apparatus according to claim 1 connecting the auxiliary lift foil to the main lift element.
11. The lift foil of claim 10 wherein the auxiliary lift foil comprises a trailing edge flap.
12. The lift foil of claim 10 wherein the main lift element comprises:
an upper aerodynamic surface;
a lower aerodynamic surface; and
a strut extending downwardly from the lower dynamic surface and carrying the first hinge.
13. The apparatus of claim 1 wherein the main lift element comprises a main wing element and the auxiliary lift foil comprises an auxiliary aerofoil.