Multi-channel extrusion screw with a zig-zag undercut barrier
US5035509A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 13, 1990 |
| Grant date | Jul 30, 1991 |
| Priority date | — |
| Expiry date | Aug 13, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/03
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A plasticating apparatus having a barrel and a screw rotatably disposed therein. The screw has a mixing section including a helical conveying flight to form a helical passage for transporting resinous material along the screw. The mixing section further includes a helical, zig-zag barrier flight spaced from the conveying flight to divide the helical passage into channels of varying cyclic depth in the helical direction of the channels. The portions of minimum depth of the channels define wave crests which are helically displaced from each other. The barrier flight has a first section converging toward one side of the conveying flight, and a second segment diverging away from the same side of the conveying flight. The plurality of first and second segments repeat throughout the mixing section.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.