Patent · US Expired

Extrusion head

US4432718A · kind A · utility

23Cited by
7References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 12, 1981
Grant dateFeb 21, 1984
Priority date
Expiry dateNov 12, 2001

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29C48/13
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

An extrusion head with an annular extrusion die gap or orifice for fabricating a hollow extrudate of thermoplastic material. The extrusion head has a central die core and outer die casing ring cooperating to define the die gap. The inner boundary of the die gap is formed by a wall of the die core, while the outer boundary of the die gap is formed by a wall of the casing ring. At least one boundary wall of the die gap comprises independently movable sections that move with respect to the other boundary wall to change the width of the die gap.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.