Method for the integral molding of a synthetic thermoplastics part
US5667745A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 1, 1993 |
| Grant date | Sep 16, 1997 |
| Priority date | — |
| Expiry date | Nov 1, 2013 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2045/5615
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method for the integral molding of a thermoplastics top on the edge of a cardboard tube, the plasticized synthetic plastics material being injected into the mold cavity formed by inner and outer mold parts, the mold parts being pressed against each other with force. To produce relatively thin plastics parts with a high degree of dimensional accuracy in the very shortest time and by using simpler tools, the mold cavity in a first stage is maintained at a large volume during which the plasticized synthetic plastics material at least partially fills the mold cavity under a relatively low pressure, the mold cavity being in a second stage conveyed to a smaller volume than that of the first stage, the clamping force for pressing together the inner and outer mold parts being increased in the second stage in relation to that in the first stage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.