Method of extrusion molding and apparatus therefor
US5202064A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Sep 16, 1991 |
| Grant date | Apr 13, 1993 |
| Priority date | — |
| Expiry date | Sep 16, 2011 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/32
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An extrusion molding method for improving the fluidity of a molding material in the die and significantly improving the productivity of the molded article of uniform thickness, and an extrusion molding apparatus adapted for smoothly carrying out the method and having an unsophisticated constructional arrangement, are disclosed. Molding is carried out while the die to which an extrusion orifice gap adjustment device is annexed is kept in resonant vibrations. The extrusion orifice gap adjustment device is annexed to a portion of the die constituting an extrusion orifice section, and molding is carried out while only the portion of the die is kept in resonant vibrations. The extrusion orifice gap adjustment device is annexed at a node of the resonant vibrations. The extrusion orifice of the die is provided at a position in register with a loop of the resonant vibrations, that is, at a position of the maximum effect of the vibrations, so that the frictional resistance between the molding material and the die surface in the vicinity of the extrusion orifice is reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.