RIBBED CORE DUAL WALL STRUCTURE

摘要

An elongated composite tube with an inner tube (42) in Fig. 3 and an outer tube (44) with a plurality of elongated ribs (46) between the inner and outer tubes which maintain the tubes in a fixed radial and axial relationship to each other. In a preferred embodiment, the ribs are disposed at alternating angles away from normal with respect to the inner and outer tubes and form elongated truss cells (49) with each cell bordered by two adjacent ribs and a portion of the inner or outer tube. A new slinky-like toy is also disclosed which is made by helically cutting the composite tube to produce a plurality of flights in a spring-like configuration. A method of making such a composite tube having helical ribs is also disclosed.