Induction apparatus and method for sealing of thermoplastic coated packing material
US4704509A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1986 |
| Grant date | Nov 3, 1987 |
| Priority date | — |
| Expiry date | Aug 13, 2006 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2995/0008
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An arrangement for the sealing of thermoplastic-coated packing material of the type which includes at least one layer of an aluminum foil. The arrangement includes an inductor (3) connectable to a high-frequency source of current which is constituted of a U-shaped loop of electrically conducting material. The legs of the U-shaped loop are parallel and are situated close to each other, and the inductor (3) a core (10) of ferrite material between its legs. The core of ferrite material has local inserts (11) of ferrite material of substantially higher permeability than the surrounding portions of the core (10) and the local inserts (11) are installed in regions of the sealing arrangement where strong local heating is required in the sealing joint or where the sealing pattern needs to be influenced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.