Timothy P Dougherty

US Patent:

45129444, Apr 23, 1985

Filed:

Jun 23, 1983

Appl. No.:

6/507262

Inventors:

Greg Astfalk - Levittown PA
Timothy S. Dougherty - Roswell GA
Montri Viriyayuthakorn - Trenton NJ

Assignee:

AT&T Technologies, Inc. - Berkeley Heights NJ

International Classification:

B29F 310

US Classification:

264174

Abstract:

Extruder tooling for directing plastic materials to enclose a conductor (26) being advanced along a path of travel through a core tube (97) and aligned dies includes disc-like flow passages (107, 129) which are disposed concentrically about and perpendicularly to the conductor. This arrangement minimizes conductor tension in a pressure extrusion arrangement by significantly reducing the length of the plastic-to-conductor contact within the extruder. The length and width of each flow passage normal to and along a path of travel are sufficient to provide a uniform distribution of plastic material circumferentially about the conductor and to dissipate stresses which have been induced in the plastic materials. In a tubing arrangement, the length of a cantilevered portion of the core tube is reduced significantly which results in improved concentricity of the plastic material about the conductor.