Fluorescent lamp for use in explosive atmospheres such as mines
US4229780A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 27, 1978 |
| Grant date | Oct 21, 1980 |
| Priority date | — |
| Expiry date | Jun 27, 1998 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21Y2103/00
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Lamp having an elongated lighting assembly and a guard assembly therefor. The lighting assembly includes an elongated fluorescent bulb characterized by hot regions at the end portions of its luminous envelope. The guard assembly includes: a tubular light-transmitting housing of polycarbonate or glass; metal end housings; and closure members closing the open outer ends of the end housings. Heat conductive metal bushings are cemented to the end portions of the light-transmitting housing. These have cylindrical bearing surfaces telescopically assembled in contiguous, lapping, heat-conductive relationship with corresponding bearing surfaces on the end housings. The metal bushings function as heat sinks and heat conductors, cooling the portions of the light-transmitting housing which are subject to radiation from the hot regions of the bulb by conducting heat through the bushings into the metal end housings which dissipate it to the surroundings. The light-transmitting housing is free to expand and contract and turn about the lighting assembly. The end housings are optionally interconnected by a guard cage overlying the light-transmitting housing, or by an external tie bar. The lighting…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.