Reduced density foam and method for molding reduced density foam
US7935294B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2006 |
| Grant date | May 3, 2011 |
| Priority date | — |
| Expiry date | Jul 9, 2027 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C44/422
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A system and method for operating an injection system to create a reduced density polymeric component uses a resin/blowing agent mixture, an injection molding machine having an injection molding screw positioned in a screw section, accumulators, a hydraulic pump, multiple molds, and a cooling system. Coolant is directed into each mold. The injection molding screw is rotated moving the mixture proximate to a receiving portion of the screw section. The injection molding screw is incrementally displaced to one of a plurality of successive injection positions each injecting a portion of the mixture into one of the molds by operating the hydraulic pump and discharging the accumulators. The accumulators are recharged after each injection molding screw displacement using the hydraulic pump. The injection molding screw is displaced and the accumulators recharged for each of the successive injection positions, each defining a stage for filling the molds in a single operating cycle of the injection system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.