Patent attributes
A variable-diameter rotor comprises a hub with a shaft and rotor blades, wherein each of the rotor blades comprises a radially internal blade part and a radially external blade part. In each of the rotor blades, a jackscrew mechanism is arranged therein and includes a jackscrew arranged in the radially internal blade part and a nut connected with the radially external blade part, the nut cooperating with the jackscrew for radially moving the radially external blade part with respect to the radially internal blade part. The rotor further comprises an energy storage system, including a compressed-gas accumulator. The compressed-gas accumulator comprises a volume of gas and a piston for compressing and expanding the volume of pressurized gas. The energy storage system also includes a means for converting a radial motion of the radially external blade part into a motion of the piston of the compressed-gas accumulator and vice-versa.