Patent Number: 6,250,908

Title: Conduit-making apparatus with a variable diameter winding drum

Abstract: An apparatus is disclosed for making a conduit or pipe. An extruder is provided for producing a strip of continuous thermoplastic. A winding drum receives the strip and helically winds the strip around the drum's perimeter to form a conduit having an inner diameter corresponding to the outer diameter of the drum. The drum includes a core tube surrounded by a plurality of rollers which define the outer diameter of the drum. The rollers rotate to advance the strip around the drum. A plurality of support columns are used to support the roller at each end. A hub assembly is used to movably support the support columns in slidable engagement. The support columns are radially displaced by the hub assembly between two positions, in order to vary the outer diameter of the drum between two diameters.

Inventors: Foos; George J. (Grand Rapids, OH)

Assignee: The Lamson & Sessions Co.

International Classification: B29C 53/82 (20060101); B29C 53/00 (20060101); B29C 47/00 (20060101); B29C 053/62 ()

Expiration Date: 06/26/2018