Restriction insert for an extrusion die
US4826422A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 13, 1988 |
| Grant date | May 2, 1989 |
| Priority date | — |
| Expiry date | Jan 13, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/10
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A restriction insert adapted to be mounted on a spider of an extrusion die has a generally hollow body formed by integral first and second conical walls wherein the first conical wall has a larger inner diameter than that of the second conical wall. A pair of spaced axially extending material inner flow passages are formed concentrically about the axial bore opening in an outer end of the second conical wall and communicates with the interior of the body. A frustro-conical shaped groove is formed in the outer end of the second conical wall within the interior of the body to provide a tapered flow path for the material entering the inner flow passages. A pair of outer flow passages are formed concentrically in an annular shoulder at the junction of the conical walls. A generally pointed annular edge is formed on the interior of the second conical wall and in combination with the tapered inner surface of the first conical wall form tapered flow paths for the material entering the outer flow passages. The outer flow passages radially overlap adjacent ends of the inner flow passages whereby two concentric sleeves of material are produced which are radially compressed together in formin…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.