Patent ID: 6231710
Filing Date: 2001-05-15
Classification: B29C,B29K,B29L,B64C,B64G,G10K,Y02T

Abstract:
A method of manufacturing a sandwich structure having an inner and outer filament wound skin with acoustic attenuation properties, the method comprising:a. pre-fabricating wedge-shaped composite material tubes sectioned to form chambers of variable volumes;b. fabricating a filament wound composite material inner skin in a generally cylindrical shape;c. placing the pre-fabricated tubes around an outside surface of the inner skin such that a longitudinal axes of the tubes are parallel to a longitudinal axis of the inner skin;d. fabricating a filament wound composite material outer skin over the pre-fabricated tubes to form an entire assembly;e. curing the entire assembly in an autoclave or oven; andf. drilling a hole through the inner skin and into each chamber of each tube to thereby convert each chamber into a Helmholtz resonator, thereby constructing a lightweight, strong, and acoustic attenuating structure.