Heat-sealing device for packaging material
US7002117B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 16, 2002 |
| Grant date | Feb 21, 2006 |
| Priority date | — |
| Expiry date | Dec 16, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2009/003
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Device for welding a moving packaging material (1) including a layer that can be heated by electromagnetic induction and a thermoplastic layer incorporating a welding zone (2) which lies in the direction of movement of the packaging material; the welding device includes an alternating current generator, a coil (3, 5, 6) for transforming the alternating current into a magnetic field, a ferromagnetic element (7, 8, 10–13) for channeling the magnetic field lines in a specific direction, the magnetic field being oriented so s to cross the packaging material (1) in order to induce heating of the layer that can be heated by electromagnetic induction; the welding device being characterized in that it includes a set of ferromagnetic elements (7, 8, 10–13, 19–21) which are arranged so that the magnetic field lines cross the packaging material (1) in at least two distinct regions (14, 16–18) located along the welding zone (2).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.