Aerodynamic devices

An aerodynamic device having a rotor coupled to retaining means which define an axis of rotation for the rotor, the rotor comprising at least one lift member formed by a wall which is generated by straight lines transverse to the said axis, which wall extends between two spaced positions on the axis and is spaced from the axis between said positions, the axis of rotation of the rotor passing through or adjacent to its center of gravity, in which at least one of said wall generating straight lines is perpendicular to said rotational axis and intersects said rotation axis, said rotational axis and said intersecting straight line defining a first imaginary plane, said first plane dividing said lift member substantially into two halves, the two halves being substantially similar in size, said rotor constituting the entire rotatable structure of said aerodynamic device, all said straight lines defining said rotor being parallel to each other, a projection of the entire rotatable structure of said aerodynamic device onto a plane parallel to but spaced from the axis of rotation and perpendicular to said straight lines consisting only of the edge outline of the rotatable structure of the aerodynamic device.

An aerodynamic device having a rotor coupled to retaining means which define an axis of rotation for the rotor, the rotor comprising a lift member formed by a wall which is generated by straight lines transverse to the said axis, which wall extends between two spaced positions on the axis and is spaced from the axis between said positions, the axis of rotation of the rotor passing through or adjacent to its centre of gravity, in which said lift member has the shape of an elongate strip of length extending along the rotation axis, said strip being bent through curves or creases at different locations along its length to enable said strip to cross the rotational axis, the strip being located symmetrically of said rotation axis so as to be substantially rotationally balanced on said axis, namely so that opposite sides of the rotational axis face toward substantially equal sized and shaped portions of said strip, said strip crossing said axis at least at three locations spaced serially along said axis.

An aerodynamic lift force producing device comprising:

• retaining means;
• means rotatable with respect to said retaining means for producing an aerodynamic lift force on said retaining means, said rotatable lift force producing means consisting of a rotor coupled to retaining means which define an axis of rotation for the rotor, the rotor comprising a lift member formed by a wall which is generated by a plurality of straight lines transverse to the said axis, which wall extends between two spaced positions on the axis and is entirely spaced from the axis between said positions, the axis of rotation of the rotor passing through or adjacent to its center of gravity, all of said straight lines defining said rotor being parallel to one another and transverse to said axis, all of said straight lines defining said wall being spaced from said axis except at said spaced positions on said axis, the length of said parallel straight lines which generate said lift member exceeding the maximum perpendicular distance by which the lift member is offset from said axis of rotation.