Bi-level light fixture for public transportation tunnels
US11490474B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 2020 |
| Grant date | Nov 1, 2022 |
| Priority date | — |
| Expiry date | Mar 30, 2040 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21Y2115/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light fixture usable in train tunnels provides normal mode downlighting for track and walkway lighting and a selective task lighting mode where higher-lumen lighting is provided in at least the same downlighting direction as the track and walkway lighting. The normal lighting illumination level is at least 0.25 to 2.00 foot-candles at the illuminated surfaces. The task lighting mode provides at least 5.00 foot-candles to the same illuminated surfaces. The task lighting mode is achieved with the same light source that provides the normal mode lighting or with additional light sources that are activated together with or instead of the normal lighting mode light sources. The light sources can be a plurality light emitting diode (LED) engines that include a plurality of LEDs. The task lighting mode can also use another light source to provide additional task lighting up from the fixture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.