Patent · US Expired

Molding apparatus including screw for molded articles of thermoplastic gas impregnated resin

US6652254B2 · kind B2 · utility

13Cited by
9References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 30, 2002
Grant dateNov 25, 2003
Priority date
Expiry dateAug 30, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S425/228
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The invention provides a molding apparatus adapted to use a screw having an overall length permitting the use of an existing molding machine cylinder as it is, and is capable of realizing a gas impregnation step. The screw 3 for use in the gas impregnation step comprises a resin melting portion C disposed at an upstream position for rendering the resin molten, a molten resin nonfilled-up portion E integral with the downstream side of the resin melting portion C for making the resin lower than an inert gas at a gas supply opening 5 in pressure, and a gas impregnation portion D integral with the downstream side of the molten resin nonfilled-up portion E for supplying the inert gas and impregnating the molten resin with the inert gas.

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