Traffic light radio control system

• US 4,135,144 A
• Filed: 03/07/1977
• Issued: 01/16/1979
• Est. Priority Date: 03/07/1977
• Status: Expired due to Term

• Current Assignee: David L. Kirk
• Original Assignee: David L. Kirk
• Inventors: Elmasian, Edward
• Primary Examiner(s): Yusko, Donald J.
• Assistant Examiner(s): Groody, James J.
• Application Number:
  US05/774,811
• Time in Patent Office: 680 Days
• Field of Search: 340/32, 340/33, 340/34, 340/43, 325/111, 325/117, 325/312, 325/314, 343/228
• US Class Current: 340/906
• CPC Class Codes: G08G 1/087 Override of traffic control, e.g. by signal transmitted by an emergency vehicle

Abstract

A radio transmitter activated traffic signal control including a radio transmitter carried in the emergency vehicle and activated to transmit a signal to the traffic signal lights at each intersection approached by the emergency vehicle which in turn activates a relay within the traffic light controls which relay disconnects the normal sequencing controls to the traffic lights and activates a timer delay relay which initially energizes the red light in each traffic signal via a blinker to cause a flashing red signal to be activated at all lights and subsequently, after an adjustable time delay period ranging from 5 to 8 seconds, energizing each red light in a steady mode. After the transmitter signal is sufficiently attenuated by the emergency vehicle proceeding a sufficient distance beyond the intersection, the receiver-activated relay is again de-energized, causing the normal sequencing and timing controls of the traffic signal to again be connected to the traffic lights for normal operation.

Claims

1. In a traffic signal light system of the type including a plurality of traffic lights of different color and including sequencing and timing circuitry and power supply therefor operative to produce energization of said plurality of lights in a predetermined time pattern to thereby regulate traffic flow, the improvement comprising:

an emergency vehicle activated controls for said plurality of lights, said controls including first relay means having contacts in series between the power supply means for said sequencing and timing circuitry, said first relay means contacts being normally closed to allow energization of said sequencing and timing circuitry by said power supply, said first relay means further including means disconnecting said sequencing and timing circuitry and said power supply means upon energization of said first relay means and opening of said contacts;

radio transmitter means selectively operated and adapted to be carried by an emergency vehicle;

radio receiver-relay means adapted to be activated by said radio transmitter means and operative when activated to activate said first relay means to disconnect said power supply means from said sequencing and timing circuitry means by opening of said contacts;

delay-relay means having an input terminal means;

a first output terminal means adapted to be connected to said input terminal means upon activation of said delay-relay means for a predetermined time period of short duration;

second output terminal means adapted to be connected to said delay-relay input means upon disconnection of said first terminal means and continuously activated as long as said delay-relay means is activated;

means activating said delay-relay means in response to activation of said receiver-relay means;

blinker means including a pair of contacts and adapted to provide a cyclical make and break of said contacts;

means connecting said first output terminal means of said delay-relay means to one of said blinker means contacts, the other of said blinker means contacts connected to one of said traffic lights, said second output terminal means connected to one of said traffic lights;

means connecting said power supply means to said input terminal means of said delay-relay means upon activation of said receiver-relay means;

whereby when said receiver-relay is energized, one of said traffic lights is initially cyclically energized via said blinker means by connection of said power supply via said first output terminal means and then by said connection to said second output terminal means, one of said traffic lights is steadily energized.

2. The traffic signal control arrangement according to claim 1 wherein said delay-relay means comprises an adjustable timer delay-relay means.

3. The arrangement according to claim 1 wherein said traffic light includes red, amber and green lights controlled by said sequencing and timing circuitry means and wherein said first input terminal means associated with said delay-relay means connects said power supply with said red light, whereby said traffic signal is initially operated in the flashing red mode and subsequently caused to be energized in a steady condition upon activation of said receiver-relay means by said transmitter means carried by an emergency vehicle.