Laser director for fire evacuation path
US6150943A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 14, 1999 |
| Grant date | Nov 21, 2000 |
| Priority date | — |
| Expiry date | Jul 14, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B7/066
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A device for projecting an escape path to direct evacuation from a fire includes a plurality of laser diode projectors secured within a housing and aimed to project successive rays or images along a predetermined escape path. The images may comprise arrow indicators, graphics, or alphanumeric indicators. The laser beams are emitted through the same window in the housing to minimize heat infiltration into the housing. The laser diodes are triggered by an alarm condition, such as direct actuation by a smoke sensor, IR detector, or the like, or secondary actuation in response to the audio alarm signal of a primary fire alarm. For actuation by a primary alarm system, a microphone input is amplified and fed to a microprocessor. The microprocessor is programmed to digitally filter and process the signal to determine the presence of a primary alarm signal, and actuate a fire escape path illuminating module. The audio pickup includes a pair of microphones spaced apart approximately one-half wavelength of the primary alarm signal to avoid acoustic standing wave problems, the microphones switching periodically to acquire the best signal. The microprocessor operates in a low power mode, and a…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.