WO1998038615A2

WO1998038615A2 - Emergency traffic light system

Info

Publication number: WO1998038615A2
Application number: PCT/US1998/003915
Authority: WO
Inventors: Keyvan T. Diba
Original assignee: Diba Keyvan T
Priority date: 1997-02-26
Filing date: 1998-02-26
Publication date: 1998-09-03
Also published as: AU6863598A

Abstract

An emergency traffic light system uses transmitter-carrying vehicles to alert indicator-carrying stop lights. The emergency vehicle transmitters transmit a unique signal for the indicators. In response to detection of the unique signal, traffic may be merely alerted to the oncoming emergency traffic or the normal 'red light/green light' transmission sequence of the stop light may be altered. The indicators detachably attach to stop lights so that easy retrofitting may take place.

Description

EMERGENCY TRAFFIC LIGHT SYSTEM

FIELD OF THE INVENTION

This invention relates to devices that modify stop light operation for emergency traffic and more particularly to a stop light indication system that responds to police, fire, and other emergency traffic by indicating a "stop" or the approach of emergency traffic to all traffic at the stop light intersection.

BACKGROUND OF THE INVENTION

Stop lights, street lights, or traffic lights are known in the art for use at intersections where oncoming traffic meets. With the use of stop lights, traffic at an intersection can be directed in a safe and efficient manner to avoid collisions and to increase the flow of traffic.

Frequently, emergency traffic such as police cars, fire trucks, and ambulances must pass through busy intersections in order to make their way to their destinations such as crime scenes, fires, and medical emergencies, respectively. In so doing, such emergency vehicles flash bright lights and emit sirens in order to alert traffic of their passage. When so alerted, such traffic pulls over to the curb in order to allow the quick and safe passage of the emergency vehicle.

Certain difficulties arise with the passage of emergency vehicles through intersections. The acoustic environment surrounding the intersection may be such that the direction of an approaching siren may be quite difficult to place. When a driver in traffic is unable to place the direction of the siren, that driver is unable to anticipate the direction of the emergency vehicle. Moreover, the driver may be unable to hear the siren at all. If the emergency vehicle is obscured by a building or other visual obstacle, the driver may in no way be aware of approaching emergency traffic at an intersection.

This can be a dangerous situation as emergency traffic is allowed to pass "against the red" at a stop light. If a driver is not alerted to the approach of emergency traffic, that driver may pass into the intersection with the green light of the stop light while, simultaneously, the emergency vehicle (s) enter into the intersection against the red. Although collisions between the vehicles incoming to the intersection may be avoided through quick response, the progress of the emergency vehicles will be slowed and their response to an emergency situation will be delayed.

SUMMARY OF THE INVENTION The present invention stops or alerts all traffic at an intersection so that emergency traffic may pass through.

A signal-responsive indicator is attached to the stop lights at intersections. When emergency traffic approaches the intersection, signals (such as radio signals) are transmitted by the emergency vehicles. The signal-responsive indicator detects the transmitted signals and indicates to all oncoming traffic the approach of the emergency vehicles. When alerted to the approach of the oncoming emergency vehicles, all other traffic may stop to allow the unimpeded progress of the emergency vehicles. The flow of ordinary traffic is only slightly impaired in a temporary manner while the flow of emergency traffic is expedited.

One type of signal-responsive stop light indicator acts as an illuminated shutter is attached to the green light portions of all the signals at the intersection. Upon the approach of oncoming emergency vehicles, a plate that fits over the green light portion of the stop light turns opaque to prevent transmission of the green light signal to the oncoming traffic. Simultaneously, sources of red light (such as LEDs) are activated to illuminate an outward mirror-like surface of the plate with red light similar to that of the regular red light of the stop light. Upon seeing the extinguishing of the green light with its replacement by red light, oncoming traffic to the stop light know that an emergency vehicle is in the vicinity and that all traffic should stop to allow the emergency vehicle to pass through the intersection.

Alternatively, an indicator may be attached to the portion of the stop light that surrounds both the lamps and the shades. Such an indicator can schematically reflect the intersection to indicate from which direction the emergency vehicle is coming. Red and amber lights can be used to indicate such direction. For both alternative embodiments of the signal-responsive indicator, solar cells may be used to power the devices and if the direction of the emergency vehicles needs to be determined, a directional antenna system can be used.

Accordingly, it is an object of the present invention to provide a system that allows approaching emergency vehicles to control the flow of traffic for upcoming intersections.

It is another object of the present invention to provide such a system that is adaptable to presently available emergency vehicles and street light systems.

It is yet another object of the present invention to provide such a system that can be solar powered due to minimum, but adequate, power requirements.

It is yet another object of the present invention to provide such a system that can indicate the direction of travel for the emergency vehicles.

These and other objects and advantages of the present invention will be apparent from a review of the following specification and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective schematic view of the emergency traffic light system showing the emergency vehicle in wireless communication with the shutter-type embodiment of the indicator. Fig. 2 is a partial sectional view of the shutter-type indicator shown in Fig. l.

Fig. 3 is an enlarged, sectional view of the glass p_late portion of the shutter-type indicator of Figs. 1 and ₂.

Fig. 4 is a perspective view of an alternative indicator embodiment atop a stop light of conventional manufacture.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As shown in Fig. 1, an emergency vehicle 10 is equipped with a transmitter 12. The transmitter 12 emits a unique signal, indicated at 14 , that is particular to emergency vehicles used in the system of the present invention. It is not required that each emergency vehicle have its own unique signals, but all emergency vehicles implementing the system of the present invention should transmit one signal that can be distinguished from non-emergency vehicles.

The signal 14 should be one that is otherwise not distracting to the general public. Preferably, the signal 14 is a unique signal in the radio frequency range, but other electromagnetic signals could also be advantageously used.

The signal 14 is continuously transmitted by the emergency vehicle 10 while it is engaged in emergency service, or while it is travelling to tend to a present emergency. One way to ensure that such signal transmission occurs is to couple the signal transmission to the sirens of the emergency vehicle. Other alternative forms of signal activation can be used, including dedicated activation such as a particular switch which directly controls the transmission of the unique emergency signal 14.

The signal 14 need not be one of tremendous strength and power. However, it should be sufficient to activate stop lights implementing the system of the present invention for several surrounding blocks without interfering with traffic that would otherwise not be involved in the emergency vehicle's response. Signal transmission strength of three to four city blocks should be sufficient for most purposes.

As the emergency vehicle 10 travels along the streets, it is continuously surrounded by an envelope defined by the transmission of the unique emergency signal 14. This signal envelope serves to activate indicators 16 responsive to the unique emergency signal 14.

As shown in Figs. 1 and 2, the indicator 16 preferably fits over the shade enshrouding the green lamp of contemporary stop lights. As the indicator 16 portion of the present system can be used with contemporary equipment, it is a simple task to retrofit existing stop lights to implement the present system.

As shown in more detail in Fig. 2, the indicator 16 has an antenna 18 by which the indicator 16 may better receive the signals 14 transmitted by the emergency vehicle 10. The antenna 18 is connected to electronic circuitry internal to the indicator 16 to control the operating features of the indicator 16. As is set forth in more detail below, the electronic circuity internal to the indicator 16 generally acts only to activate and deactivate certain features of the indicator. As such, the circuitry internal to the indicator 16 may be of any number of particular designs that are currently known in the art.

Covering the open end of the shade S enshrouding the lamp L of the stop light W, is a glass or plastic plate 20 of particular sandwiched construction. As currently contemplated, the plate 20 has a first, rigid outer layer 22; a second, electro-optically active middle layer 24; and a third, rigid inner layer 26. The outer and inner layers 22, 26 serve to support the middle layer 24. Further, when the middle layer 24 is opaque, the outer layer 22 is preferably highly reflective of local incident light. The middle layer 24 of the plate is electro-optically active and may use a liquid crystal display (LCD) to attain its electro-optical activity.

The indicator 16 encircles the open end of the shaded lamp L by a snugly fitting structure 28 composed of the same general material as the body of the indicator 16. The plate 20 fits within which enclosing structure 28 towards an end closest to the lamp L. Towards the other end of the enclosing structure 28 at regularly spaced intervals within the circle there defined are a series of red light sources 30 such as light-emitting diodes (LEDs) or the like. The red light sources 30 are placed so that they may be reflected by the plate 20 when it becomes opaque.

In order to provide more operating features for increased ease and facility, the indicator 16 has a data display 32 through which additional indicator operating information may be provided for installation and repair. The data display 32 can also display other messages regarding operation status and function to the interested observer.

Switches and/or other indicator controls, indicated generally at 34, can be placed on one side of the indicator 16 to control the operation of the indicator 16. Such controls may include selection of the. receiving frequency for the indicator 16. As shown in Fig. 1, a compass or other directional indicator 36 may be place atop the indicator 16. Such a compass 36 can serve to orient the indicator 16 to its particular fixed direction should the need for directional information or data be required in its operation.

When the indicator 16 receives a signal 14 from an emergency vehicle 10, the signal 14 is first received by the indicator's antenna 18. The circuitry internal to the indicator 16 detects and recognizes the presence of the unique emergency vehicle signal 14 and responds appropriately by activating the plate 20 and the red lights 30. This is in contrast to normal, unactivated operation of the indicator 16 when no emergency vehicle signal 14 has been detected by the internal circuitry.

During normal, unactivated operation, the indicator 16 is receiving no emergency vehicle signals 14. During these times, the light from the green lamp L is allowed to pass through the plate 20 unobstructed and the operation of the stop light W is the same as that for any other ordinary stop light that does not implement the present system.

However, upon activation by reception of an emergency vehicle signal 14, the indicator 16 responds very quickly to control non-emergency traffic. When the internal circuitry of the indicator 16 detects an emergency vehicle signal 14, signals are transmitted by the internal circuitry to the plate 20 and to the red light sources 30. In response to these signals, the plate 20 becomes opaque and does not allow the light from the green lamp L to be transmitted past the plate 20. Oncoming traffic then no longer sees a green light when an emergency vehicle is responding nearby. Further, the red light sources 30 also respond to the internal circuitry's signal by emitting red light. This red light is reflected by the first, outer layer 22 of the plate 20 so that, as the green light is extinguished by the middle LCD layer 24 of the plate 20, red light is emitted by the indicator 16 and reflected off of the plate 20 to be seen by oncoming non-emergency traffic. In this way, the otherwise green light of the stop light

W becomes a red light so that the traffic flow can be stopped at that intersection to allow passage of an emergency vehicle.

Referring now to Fig. 4, an alternative embodiment of the indicator 16 of Figs. 1 and 2 is shown. The alternative indicator 38 attaches as by bolts 40 through a plate 42 to an upper corner of a stoplight W.

The indicator 38 is arranged in a "+" or cross arrangement, as is shown in Fig. 4. This cross arrangement serves to represent the intersection to oncoming traffic and certain adaptations of the cross arrangement may be require_{d f}or irregularly shaped intersections.

The ends of the left side arm 44 and the right si_de arm 46 are connected by struts 48 and 50 respectively to the top o_f the top arm 52. As shown in Fig. 4, the right side arm 46 and the lower arm 54 fit snugly adjacent to the corner of stop light W; however, other ways and means of attachment to the stop light W are possible.

Four antennas 56a-d are attached to the bottom of the left side arm 44. These four antennas 56a-d may be attached elsewhere about the indicator 38 and are used to detect not only the signal from the oncoming emergency vehicle, but also the direction from which the emergency vehicle is coming.

When the emergency vehicle signal is received by one or more of the antennas 56a-d, the signal is relayed via the antenn (s) to circuitry internal to the indicator 38. Upon recognition of a valid emergency vehicle signal, the internal circuitry can determine from the four signals corresponding to the four antennas 56a-d from which direction the emergency vehicle is coming.

When a valid emergency vehicle signal is recognized by the indicator 38, indicator lights are used to inform oncoming traffic of the direction and approach of an emergency vehicle. At the ends of each of the arms 44, 46, 52, 54 is a red light 58, 60, 62, 64 respectively, that may be circular in shape. There is also a red light 66 at the center of the indicator 38. A series of colored lights 68, 70, 72, 74 are intermediate the central red light 66 and the red lights 58, 60, 62, 64 at the ends of the arms. The indicator lights serve to indicate both the presence and direction of the approaching emergency vehicle 10. After receiving and recognizing the emergency vehicle signal 14, the indicator's 38 internal circuitry flashes the indicator lights as follows. First, the red light at the end of the arm corresponding to the present location of the emergency vehicle is flashed. Next, the amber lights are flashed in sequence to lead an observing driver's eye toward the center red light 66. Finally, the center red light 66 is flashed. This flashing sequence of indicator lights is repeated throughout the approach of the emergency vehicle. By means of the indicator 38, traffic can anticipate the presence and direction of approach of an emergency vehicle 10.

Power for the alternative indicator 38 is supplied by a panel of solar cells 76 present along the top of the struts 48, 50.

With the use of solar cells, external power supply requirements are diminished or eliminated.

While the present invention has been described with regards to particular embodiments, it should be understood that additional variations of the present invention may be devised without departing from the inventive concept.

Claims

WHAT IS CLAIMED IS:

1 Claim 1. An emergency traffic light system 1

2 comprising: 2

3 a transmitter, said transmitter coupled to 3

4 an emergency vehicle and emitting a unique signal 4

5 when the emergency vehicle responds to an emergen-5

6 cy; and 6

7 an indicator releasably attachable to a stop 7

8 light, said indicator having a receiver responsive╬┤

9 to said unique signal of said transmitter, said 9

10 indicator then indicating the approach of the 10

11 emergency vehicle and directing traffic to acco- 11

12 modate the emergency vehicle; 12

13 said indicator comprising: 13

14 a body, the body nondistructively attachablyl4

15 detachable to a shroud about a green light of a 15

16 stop light and defining an aperture therethrough 16

17 by which the green light may be transmitted to 17

18 traffic: 18

19 a plate, the plate having first, second and 19

20 third layers, the second layer electro-optically 20

21 responsive by controllably transmitting and bloc-21

22 king light travelling therethrough, said first 22

23 layer capable of reflecting light; 23

24 a series of red lights adjacent to and en- 24

25 circling said plate; and 25 circuitry responsive to said unique signal 26 and causing said red lights to turn on and cau- 27 sing said plate to become opaque and to reflect 28 the incident red light so that traffic may be 29 alerted to the oncoming emergency vehicle. 30

Claim 2. The emergency traffic light system 1 of Claim 1 wherein: 2 said transmitter is coupled to a siren pre- 3 sent in the emergency vehicle. 4

Claim 3. The emergency traffic light system 1 of Claim 1 wherein: 2 said indicator responds to said unique signal3 by blocking the further transmission of a green 4 light of the stop light. 5

Claim 4. The emergency traffic light system 1 of Claim 3 wherein: 2 said indicator responds to said unique signal3 by transmitting a red light signal to the traffic.

Claim 5. The emergency traffic light system 1 of Claim 1 wherein: 2 said indicator detects a relative location 3 of the emergency vehicle and indicates to the 4 traffic a path of approach for the emergency ve- 5 hide. 6

Claim 6. The emergency traffic light system 1 of Claim 5 wherein: 2 said indicator indicates such path of ap- 3 proach by a series of flashing lights. 4

Claim 7. The emergency traffic light system 1 of Claim 1 wherein: 2 said indicator light further comprises: 3 mutually perpendicular arms with red lights 4 capable of flashing at far ends thereof; 5 a series of amber lights along each arm; 6 a central red light; and 7 a directional antenna array; whereby the red 8 and amber lights may be controlled by circuitry 9 internal to the indicator to flash in a sequen- 10 tial manner indicating a direction of approach 11 for the emergency vehicle upon receiption of the 12 unique signal. 13

Claim 8. An emergency traffic light system 1 comprising: 2 a transmitter, said transmitter coupled 3 to an emergency vehicle and emitting a unique sig-4 nal when the emergency vehicle responds to an 5 emergency; and 6 an indicator attachable to a stop light, said7 indicator having a receiver responsive to said 8 unique signal of said transmitter, said indicator 9 then indicating the approach of the emergency ve-10 hide and directing traffic to accomodate the 11 emergency vehicle; 12 mutually perpendicular arms with red lights 13 capable of flashing at far ends thereof; 14 a series of amber lights along each arm; 15 a central red light; and 16 a directional antenna array; whereby the 17 red and amber lights may be controlled by cir- 18 cuitry internal to the indicator to flash in a 19 sequential manner indicating a direction of ap- 20 proach for the emergency vehicle upon reception 21 of the unique signal. 22