Patent · US Expired

Injection molding method with stamping compression

US5093049A · kind A · utility

23Cited by
6References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 16, 1990
Grant dateMar 3, 1992
Priority date
Expiry dateMar 16, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S425/808
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

An injection molding method with stamping compression obtains an optical lens or other molded article from thermoplastic resin. A cavity is heated to a temperature at which resin can be maintained in a molten state under normal temperature. Measured and molten resin is injected into the heated cavity through a sprue part, a runner part and a gate part. After the injection, the sprue part is sealed. The injected resin is maintained in the molten state at this time. The injected resin is then hardened in the heated cavity by applying a pressure which can provide a dynamic modulus of elasticity of the resin at the normal temperature and normal pressure. The resin hardened by the pressurization is then cooled to a removal temperature while reducing the pressure so as to maintain the dynamic modulus of elasticity of the resin at the dynamic modulus of elasticity of the resin at normal temperature and normal pressure.

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