Emergency vehicle warning and traffic control system
US4775865A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 1987 |
| Grant date | Oct 4, 1988 |
| Priority date | — |
| Expiry date | Jul 10, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08G1/087
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A system for providing early warning of the approach and egress of emergency vehicles in which the warning system provides a display to indicate the direction from which the emergency vehicle is approaching and in addition provides preemption control of the traffic signals at an intersection. A transmitter mounted on an emergency vehicle transmits a signal whenever it is on an emergency call which is received by infrared (I.R.) receivers positioned at an intersection to respond to the transmitted signals. The received signal is then processed by a master controller which in turn pre-empts operation of traffic signals to control traffic flow at the intersection to which the emergency vehicle is approaching. The master controller also provides an output to display signs facing approaching traffic on each road approaching the intersection which displays messages and symbols indicating the direction of the approaching emergency vehicle. Additionally, the display system indicates whether the emergency vehicle has passed through and is departing the intersection. After a predetermined interval when an emergency vehicle has passed through an intersection the display system is deactivated …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.