Method of throttle-valving control for the co-extrusion of plastic materials
US6187241A · kind A · utility
17Cited by
8References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 14, 1998 |
| Grant date | Feb 13, 2001 |
| Priority date | — |
| Expiry date | May 14, 2018 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2045/1614
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A multiple-plastic stream co-extruder, as for injection-molding cavities, in which the extruder is internally provided therewithin and therealong with a restrictor or throttle pin, rod or element that forces combined plastic material streams, formed with an interior core stream encased in outer and inner stream layers, into corresponding concentric annular flow stream layers that are ultimately split transversely in opposite directions into a cavity gated to the extruder, and with the core stream at a region of zero gradient in the transverse flow velocity profile within the extruder and cavity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.