Discontinuous blowing agent delivery system and method
US6602063B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 21, 2000 |
| Grant date | Aug 5, 2003 |
| Priority date | — |
| Expiry date | Dec 12, 2020 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C44/60
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention provides a blowing agent delivery system and method for introducing a blowing agent into a polymeric foam processing system. The delivery system is designed to introduce blowing agent into polymeric material within an extruder when polymeric material is being plasticated, for example, during the plastication period of an injection molding cycle. The rate of introduction of blowing agent into polymeric material may be coupled to the flow rate of polymeric material in the extruder to ensure precise control over blowing agent percentage in the resulting mixture of polymeric material and blowing agent. The delivery system is also designed to prevent the introduction of blowing agent into the polymeric material when polymeric material is not being plasticated, for example, during the injection period of an injection molding cycle. The delivery system may be used in conjunction with discontinuous systems including injection molding or blow molding systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.