Paul A Davidson

US Patent:

D356732, Jan 23, 1990

Filed:

Jul 10, 1987

Appl. No.:

7/073118

Inventors:

Paul J. Davidson - Woodland Hills CA
Michael R. Smith - Thousand Oaks CA

Assignee:

E-Lite Limited - Woodland Hills CA

US Classification:

D20 42

US Patent:

47758651, Oct 4, 1988

Filed:

Jul 10, 1987

Appl. No.:

7/072336

Inventors:

Michael R. Smith - Thousand Oaks CA
Paul J. Davidson - Woodland Hills CA
Henry L. Pfister - Torrance CA

Assignee:

E-Lited Limited, A California Limited Partnership - Woodland Hills CA

International Classification:

G08G 107

US Classification:

340906

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.