Patent ID: 9267570
Filing Date: 2016-02-23
CPC Classification: F16F,H02K,Y02E,Y10T

Claim Text:
1. A hub for use in a high-speed flywheel rotor assembly as part of an overall flywheel system, the rotor assembly including a shaft that supports said hub which, in turn, supports a rim such that the rotor assembly exhibits at least one predetermined bending mode frequency, said hub comprising: an annular hub body defining an axis of rotation and having a hub length extending along the axis of rotation from a first end to a second, opposing end, said first end defining an inside diameter for engaging an outside diameter of said shaft for co-rotation therewith and said second end defining an outside diameter for engaging an inside diameter of said rim, said annular hub body formed in a layered configuration at least including a first layer that includes at least first fibers supported in a first matrix such that the first fibers form at least a portion of the fibers that make up the first layer, and at least a portion of each one of the first fibers is aligned in a fiber orientation that defines at least a projection along an axial direction that lies within a plane, bisecting the hub and also containing the axis of rotation; and a second layer that annularly surrounds the first layer and which includes at least second fibers supported in a second matrix such that the second fibers form at least a majority of the fibers that make up the second layer and the second fibers are limited to another fiber orientation that is transverse to the axis of rotation, wherein said first layer and said second layer exhibit a first radial stiffness and a second radial stiffness, respectively, as a resistance to expansion in a radial direction responsive to a rotation of said rotor assembly, and the first and second layers are configured to cooperate with one another so that said hub body exhibits a radial hub body stiffness that varies along the length of said hub body such that said second end of said hub body expands, responsive to said operational rotation, for maintaining said engagement with said inside diameter of said rim, at least up to and including a predetermined maximum rotational speed of said rotor assembly.