Light degradation sensing led signal with visible fault mode
US6667623B2 · kind B2 · utility
83Cited by
5References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 7, 2001 |
| Grant date | Dec 23, 2003 |
| Priority date | — |
| Expiry date | Feb 11, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light emitting diode (LED) signal with an LED light output monitoring sensor. If the LED light output drops below a pre-set level, an output signal of the sensor via a comparator and deactivation circuit, deactivates one or more LEDs creating a visible fault display aspect, thereby visually indicating signal failure but allowing a continued use of the signal prior to replacement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.