Patent · US Expired

Crosshead

US4280801A · kind A · utility

24Cited by
14References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 1979
Grant dateJul 28, 1981
Priority date
Expiry dateMay 30, 1999

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB29L2031/3462
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A crosshead for extruding an annular layer of thermoplastic material about a central longitudinal axis. The crosshead comprises a die having an annular slotted die opening surrounding the axis, a transverse inlet passageway for receiving molten thermoplastic material, an annular cavity connected to the inlet passageway, an annular distribution passage connected to the annular cavity and an annular connecting passage extending from the annular distribution passage to the die opening. The annular cavity and annular distribution passage each extend radially with respect to the longitudinal axis. Two or more layers of thermoplastic material are extruded by the crosshead when it is equipped with two or more dies.

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