Filament wound structure having filament wound reinforcing rings for use

Abstract

A filament wound fiber reinforced resin matrix composite structure. The structure is particularly adapted for use as a torque drive diaphragm in a rotary wing aircraft hub. The structure comprises a substantially flat diaphragm, a rim, rim reinforcement fibers and at least one fiber reinforcement ring. The diaphragm has a central attachment means for receiving a shaft and the rim has an attachment means. An alternative embodiment of the structure is a hollow disc having first and second substantially flat diaphragm sides with a connecting rim, rim reinforcement fibers and at least one fiber reinforcing ring for each diaphragm side. The sides have centrally located attachment means. The structure comprises a resin matrix, fibers wound substantially tangentially to the central attachment means with sufficient tension in a multiple circuit pattern to form the structure, fibers wound with sufficient tension in an essentially circumferential manner to reinforce the rim of the structure and fibers wound substantially circularly to form rings for reinforcing the diaphragm. The structure is cured by molding with sufficient heat and temperature in a controlled cure cycle. The structure does not exhibit 'oil-canning' in that the flat diaphragm or diaphragm sides do not displace from the substantially flat uniplanar mode when subjected to varying temperatures. In addition, the structure does not buckle under heavy torque loading. The spring characteristics of the structure when constrained as a torque drive remain approximately linear and buckling and snap-through are eliminated during operation.