Flywheel including a cross-ply composite core and a relatively thick composite rim

摘要

A flywheel includes a cross-ply composite central portion including a plurality of fiber-containing layers and a relatively thick rim portion of circumferentially wound fibers impregnated with a binder. The relatively thick rim portion surrounds the central portion and is of sufficient radial thickness such that the ratio of the outer radius of the central portion to the outer radius of the rim portion is equal to or less than 0.90. The rim and central or core portions are secured together by a relatively large interference fit of at least 0.001 inch per inch of the outer radius of the rim. Such interference fit substantially precludes failure of the flywheel by rim-core separation as would occur in similar flywheels having such relatively thick rims in the absence of the aforesaid large interference fit. The tangential modulus of elasticity of the rim-portion fibers is substantially greater than the corresponding modulus of the core-portion fibers. The flywheel typically exhibits increased energy storage capacity with maximum utilization of the stress-strain properties of both the core fibers and the rim fibers.