Energy storage rotor with flexible rim hub

Claim 1

An energy storage rotor comprising a unitary metallic hub defining a center of rotation, said hub having a plurality of spaced apart spokes and a continuous rim to which said spokes are integrally connected at spaced apart locations, and a composite ring surrounding said rim, wherein said rim is in a tight interference fit with the composite ring at rest and behaves essentially as a solid body at lower rotational speeds, and wherein those portions of the rim disposed between said spokes are adapted to deflect radially outwardly under the influence of centrifugal force when in use at higher rotational speeds so as to follow the centrifugal force-induced radial expansion of the composite ring surrounding the rim such that at said higher rotational speeds portions of said composite ring can lift away from the rim of the hub at said locations where said spokes are connected to said rim and so that a tight fit between the rim and the ring is maintained at all operating speeds of the rotor and further wherein said rim portions between said spokes define respective radially inwardly directed curved surface portions each having a center of curvature which is located radially outwardly of said center of rotation such that each of said rim portions becomes thinner toward a central portion between adjacent said spokes.