Patent · US Expired

Injection molding apparatus for forming a composite, foam-skin, article

US3966372A · kind A · utility

40Cited by
7References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 16, 1974
Grant dateJun 29, 1976
Priority date
Expiry dateMay 16, 1994

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S264/83
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A first thermoplastic resin for forming the shell of an article is charged into the front portion of an injection cylinder and a second thermoplastic resin for forming the core of the article is charged into the rear portion of the injection cylinder. Both resins are substantially separated, being in contact only a central area of the cross-sectional plane of the injection cylinder. These thermoplastic resins are injected in a mass into a mold cavity with the second resin enveloped by the first resin, and finally solidified in the mold cavity resulting in a molded article having sandwich construction. Various sandwich articles can be obtained easily by means of a single injection molding machine. The process also allows repeated injection operations without exposure of the core material on the surface of the molded article.

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