Screw extruders
US4462692A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 2, 1983 |
| Grant date | Jul 31, 1984 |
| Priority date | — |
| Expiry date | May 2, 2003 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2948/92895
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An extrusion apparatus having a barrel and a rotatable threaded screw coaxially positioned therein is disclosed. The apparatus includes an upstream inlet section having an opening therein for receiving material to be processed by the apparatus, a compression section downstream of the inlet section, and a mixing or plasticizing section downstream of the compression section. The interior surface of the barrel is provided with an undercut therein which intercommunicates the feed opening with the compression section and has a portion thereof which extends downstream in the compression section about the interior surface of the barrel with a continuously decreasing cross-sectional area. The undercut may be formed in a cylindrical insert carried within the barrel and, in an alternate embodiment, a second undercut cylindrical insert positioned about the first insert and rotatable relative thereto may be employed to vary the cross-sectional area of the undercut.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.