Reinforced cross-ply composite flywheel and method for making same

A cross-ply composite flywheel comprising a plurality of fiber-containing layers, the fibers of each layer being parallel to each other and extending in radial and chordal directions and being disposed in a matrix of binder material, the fibers of each successive layer being oriented at a single predetermined angle of between approximately 70.degree. and approximately 110.degree. to the fibers of the preceding adjacent layer such that at least four of the fiber-containing layers are disposed between any two layers in which the fibers of both such layers extend substantially parallel to each other, said flywheel having in combination therewith means for radially outward transfer of centrifugal loading from the radially outermost chordal fibers of each layer of said cross-ply composite flywheel, said load-transfer means being an outer rim contiguous with said cross-ply composite flywheel and of an axial thickness at least as great as that of said flywheel, said outer rim comprising a multiplicity of circumferentially extending fibers disposed in a matrix of binder material, the density-to-stiffness ratio of said rim being substantially less in value than the density-to-stiffness ratio of said cross-ply composite flywheel.

A flywheel comprising a plurality of fiber layers, the fibers of each layer being parallel to each other an extending in radial and chordal directions, said layers being embedded in a monolithic matrix of binder material, the fibers of each successive layer being oriented at a single predetermined angle to those of the preceding adjacent layer such that at least four layers of fibers are disposed between any two layers in which the fibers of said two layers extend substantially parallel to each other, said predetermined angle having a value between approximately 70.degree. and approximately 110.degree., said flywheel having in combination therewith means for radially outward transfer of centrifugal loading from the radially outermost chordal fibers of each layer of said flywheel, said load-transfer means being an outer rim contiguous with said flywheel and of an axial thickness at least as great as that of said flywheel, said outer rim comprising a multiplicity of circumferentially extending fibers disposed in a matrix of binder material, the density-to-stiffness ratio of said rim being substantially less in value than the density-to-stiffness ratio of said flywheel.