Heat treating thermoplastic sheet materials for thermo-forming
US4687612A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1986 |
| Grant date | Aug 18, 1987 |
| Priority date | — |
| Expiry date | Jun 20, 2006 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C35/045
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An apparatus for, and a method of, heating a thermoplastic material in web form in readiness for forming three-dimensional objects therefrom in a thermo-forming process involves (a) advancing the web material intermittently through a heating zone on a belt conveyor without imposing thereon any mechanical stress-inducing physical constraints (such as may be applied by material gripping means), and (b) sweeping the web material with a series of hot air jets which are spaced apart in the direction movement of the material, which extend transversely across the width of the material, and which are reciprocated in that direction in a manner such as to ensure a uniform heating of the web material passing out of the heating zone to a thermo-forming apparatus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.