Screw extruder for thermoplastic synthetic foams
US4222729A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 7, 1979 |
| Grant date | Sep 16, 1980 |
| Priority date | — |
| Expiry date | Feb 7, 1999 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2948/92904
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A cooling/mixing device having no moving parts is interposed between the extrusion head and the screw barrel of the extruder. The device comprises a cooled metallic block having a pair of large opposed faces and a plurality of rows of through-passages interconnecting said faces. Inlet and outlet manifold channels for the melt extend along the rows of passages so that a lateral wall of a manifold channel is formed by its respective face of the block. Partial flows of melt obtained from the flow in the inlet manifold channel are individually cooled in the passages and emerge from the latter substantially perpendicularly to the outlet flow in the output manifold channel to produce turbulent mixing. Preferably a further similar cooling block is provided, acting in series with the first block. The blocks are preferably in form of cylindrical sleeves with through-passages directed radially while the manifold channel are directed axially at the inside and at the outside of the sleeves.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.