Apparatus for making corrugated tubing

Claim 1

Apparatus for making corrugated rubber tubing from a sleeve composed of unvulcanized rubber of substantially uniform cross section comprising an elongated mandrel adapted to support a sleeve of uncured rubber and a forming member supported in fixed relation with respect to the mandrel, said forming member having inwardly facing, immovable edge means defining a surface coaxial with and surrounding said mandrel and spaced sufficiently therefrom to admit the positioning of a sleeve on said mandrel and within said forming member by longitudinal movement along said mandrel, means for creating a differential fluid pressure between the interior and exterior of said sleeve to expand the sleeve, said edge means providing a plurality of continuous, uninterrupted turns fixed with respect to each other and with respect to the mandrel and being adapted to form embryonic corrugations in a sleeve positioned on said mandrel upon expansion of the sleeve into engagement with said edge means and said forming member comprising shaping means permanently secured to an elongated member extending parallel to said mandrel, and means at one end of said elongated member and said mandrel for supporting said shaping means as contilevers.