Collapsible tube structure

Claim 1

A collapsible tube assembly comprising a tubular body having a flexible side wall that includes a sheet of ductile metal coextensive throughout, a dispensing head structure of relatively stiff solid non-metallic synthetic plastics material at one end of said body, said head structure comprising an integral inner element composed of relatively hard synthetic plastics material having an annular tapered shoulder and an annular skirt around the larger end of the shoulder having an external smooth cylindrical surface extending longitudinally from an annular corner junction with the outer periphery of said shoulder, said body at one end having a longitudinally extending cylindrical wall region of appreciable area closely surrounding said cylindrical skirt surface and terminating in an annular end region inwardly turned over said junction to overlie the outer surface of said shoulder in a substantially dead fold crimped condition, and an integral outer element of said head structure composed of a relatively resilient synthetic plastic material having an annular tapered shoulder closely overlying said shoulder of the inner head element to clamp said crimped inturned body end region between said shoulders to anchor said body against longitudinal separation from said head structure, a reduced diameter hollow neck projecting axially from the smaller end of the shoulder of said outer head element, a hollow neck projecting axially from the smaller end of the shoulder of said inner element axially forced into a tight smooth surfaced friction fit within and lining said neck of the outer head element, and a longitudinally extending annular skirt around the larger end of the shoulder having an internally smooth cylindrical surface extending longitudinally from an annular corner junction with the outer periphery of the shoulder of said outer head element closely surrounding said cylindrical wall region of the body, said skirts being longitudinally coextensive for a sufficient distance from their respective shoulder junctions to define a longitudinal space between them of constant thickness wherein said cylindrical wall region of the body is tightly radially clamped with a force fit to provide a fluid tight seal independent of the anchor between said shoulders.