Rotary device, for instance an air mover such as a fan, a propeller or a lifting rotor, a water turbine or a wind turbine

A rotary device for converting one form of energy to another form of energy, which forms of energy are electrical energy and the energy of a flowing medium, the device comprising:

• a frame with an inlet and an outlet and a rotation-symmetrical guide for the flowing medium extending between the inlet and the outlet;
• a rotor supported rotatably at least during operation by said frame and having a central hub and a number of blades which are connected to said hub in angularly equidistant arrangement and which extend at least in a radial direction, which blades all have a form such that a relation between the flowing medium and the rotation of the rotor is obtained;
• the rotor comprising a concentric ring to which ends of the blades are connected;
• the ring having a first truncated conical surface and a second truncated conical surface equal to the first truncated conical surface, the first truncated conical surface and the second truncated conical surface having mutually opposite orientations and having a radial section with a general shape of an isosceles triangle or trapezium, the base of the isosceles triangle or trapezium extends parallel to the central axis and the sides of the isosceles triangle or trapezium converge radially outward;
• the medium guide having an encircling recess, the form of which corresponds to that of the ring such that the ring fits with clearance into the encircling recess;
• and
• energy converting means, one part of which is connected fixedly to the frame and another part is connected fixedly to the rotor, the energy converting means comprising:
• magnets on each of the truncated conical surfaces corresponding to said sides, which magnets are placed angularly equidistant spaced apart at a first pitch and the poles of each magnet debouching on said truncated conical surfaces, wherein a width of the space between the magnets is less than a width of the magnets;
• and
• electromagnets having poles, the poles of the electromagnets being placed equidistantly which poles of the electromagnets debouch on both corresponding surfaces of the encircling recess facing the ring;
• wherein the ring with the magnets and the frame with the electromagnets together form an annular electrical motor or an electric generator, and wherein first poles of the magnets at the first truncated conical surface are placed such that the first poles are offset half the first pitch relative to second poles of the magnets at the second truncated conical surface.