Method and apparatus for extrusion coating of fluorescent light tubes
US7572479B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 2003 |
| Grant date | Aug 11, 2009 |
| Priority date | — |
| Expiry date | Apr 1, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/50
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for coating the glass envelope and portions of the end caps of fluorescent light tubes in a continuous and sequential manner with a thermo-plastic material. The coating is applied by a cross head extruder through which the light tubes are sequentially fed. A vacuum applied during the coating process promotes direct and intimate contact between the coating and the light tubes. The end caps may be heated prior to coating to ensure adherence of the coating to the end caps and not to the glass envelope. Post-coating processes include cooling the coating, severing individual light tubes from the chain of sequentially coated light tubes, and readying the coated light tubes for packaging. The method is automatic, with the apparatus being automatically controlled by a control unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.