Abstract:
An emergency vehicular traffic control apparatus is disclosed and claimed. A process for supplying emergency power to a traffic signal is disclosed and claimed. Emergency energy may be stored in a deep cycle battery, compressed air energy storage, or hydrogen tank (fuel). The energy source may be mounted adjacent existing control stations or it may be mounted inside the large metal poles typically used to support traffic signals.

Description:
FIELD OF THE INVENTION  
         [0001]    The invention is in the field of emergency traffic signal control.  
         BACKGROUND OF THE INVENTION  
         [0002]    California has been hard hit with a recent electrical energy crisis. Simply put, the energy crisis is real. Nearly 30 years ago the government warned that the United States of America was running short of power in the form of hydrocarbons. Energy production, particularly electrical energy, has been greatly curtailed due to environmentalism. California is particularly a victim of such environmental extremism. Everyone believes in a healthy environment and a secure future for the inhabitants of the United States of America to come after them. Nonetheless, adequate electrical power supply is necessary to enjoy a safe and prosperous future.  
           [0003]    California has faced rolling blackouts. The blackouts are indiscriminate and cause a cessation of power to controllers which control traffic signals. Motorists without traffic signals simply don&#39;t know what to do. Many motorists don&#39;t stop as they should when a signal is not functioning. This has caused loss of life and limb in California in numerous accidents. The problem (lack of reliable utility generated power) is not expected to get any better in the near future. In addition to a lack of power due to a lack of electrical generating capacity, power may be lost through natural catastrophes such as wind, hurricanes, tornadoes, and the like.  
           [0004]    Therefore, there is a need to control vehicular traffic at intersections everywhere upon the loss of electrical power from the utility. An interesting article entitled “Physical Limits of Portable Power Storage” by Michael Patrick Johnson can be found at http://aries.www.media.mit.edu/people/aries/portable-power/power.html. Mr. Johnson&#39;s article discusses portable power storage in the form of flywheels, compressed air tanks, ultra capacitors, and fuel cells. In particular he discusses hydrogen oxygen fuel cells. Mr. Johnson expresses in his article that 548 Watt-hours of energy may be obtained from a one liter tank of hydrogen at 3000 psi using a hydrogen-air fuel cell.  
           [0005]    Similarly, Mr. Johnson claims that 12 Watt-hours of energy may be stored in a one liter tank of air compressed to 3000 psi. Mr. Johnson further states that a theoretical efficiency of the turbine may be as high as 40% which yields 5.75 Watt-hours of energy per liter of air compressed to 3000 psi. A marine battery which is a deep cycle battery will supply between 2000 Watt-hours and 4800 Watt-hours when used in conjunction with a powerverter aps unit such as that supplied by trip light power protection. Powerverter aps units automatically sense and switch AC output between an outside power source such as a utility and battery power when no AC power is available. The power supplied to the load will provide the energy at 120 VAC at a frequency of 60 cycles per second.  
           [0006]    Compressed air under high pressure has been effectively demonstrated as a fuel to run automobiles. French Engineer Guy Negre has developed a compressed air driven automobile whose compressed air tank is recharged by a standard electrical outlet and compressor driven by an electric motor. Mr. Negre&#39;s concept, known as the Zero Pollution concept, can be viewed on the internet at http://www.zeropollution.com/zeropollution/body_concept.html.  
           [0007]    Horizon Signal Technologies at http://www.horizonsignal.com/specs.htm cites Horizon&#39;s portable traffic system which utilizes a deep cycle battery to power a signal. Signalman, another portable traffic control system found on the internet at http://www.signalman.net/, discloses a battery powered signal device based on U.S. Pat. No. 5,001,475.  
           [0008]    Traffic signals are the subject of an article entitled “Traffic Signals” found at http://members.home.net/traffic-signals/information/basic.htm. This article defines the equipment used in controlling vehicular traffic. The article cites the fact that North American traffic controller cabinets normally run on 120 VAC power. Traffic signals which are defined in the article as traffic signal heads are constructed of cast aluminum or plastic for low weight. The article further cites that the signal heads are illuminated by special traffic signal incandescent light bulbs having power requirements which range from 69 to 135 watts. The article further cites new LED (light emitting diode) signal heads which conserve power by using only 10 watts.  
           [0009]    Many intersections now have signals which employ traffic signal heads which require  12  light bulbs to be lit at a time. Therefore, to be conservative approximately 2000 Watt-hours of energy are necessary to power a modern intersection.  
           [0010]    U.S. Pat. No. 5,001,475 to Scovin discloses a portable traffic control device which includes an upright double sided human shaped figure which simulates a traffic control officer. The portable traffic control device is powered by two batteries.  
           [0011]    U.S. Pat. No. 6,153,943 to Mistr, Jr. discloses a power conditioning apparatus with energy conversion and storage. The &#39;943 patent discloses a gas storage reservoir in combination with a regulated fuel supply to supply electrical energy when economic conditions dictate. The &#39;943 patent is an apparent outgrowth of the electrical energy deregulation programs which are currently sweeping the United States.  
           [0012]    Ironically, it appears that electrical energy deregulation has contributed to a shortfall in the available electrical energy in California which is in fact making the problem of intersection traffic control a very bad one.  
           [0013]    U.S. Pat. No. 6,204,572 B 1 to Liran discloses a power supply for providing instantaneous energy during an electrical utility outage. The &#39;572 patent uses a flywheel to accommodate for transient conditions when utility power is lost but it also uses a backup supply generator for the continuous supply of electrical energy as needed.  
         SUMMARY OF THE INVENTION  
         [0014]    The instant invention is an emergency vehicular traffic control apparatus. The process for supplying emergency power to a traffic signal is disclosed herein. Emergency energy may be stored in a deep cycle battery, compressed air or in a hydrogen tank. The deep cycle battery is used in conjunction with a charger and inverter. Energy from the utility is supplied to the load, in this case the load is a traffic control station within a control box or cabinet. The energy from the battery, compressed air, and/or hydrogen tank is converted into usable alternating current at 120 VAC (60 Hz) which is then supplied to the control station. By control station is meant a traffic controller cabinet. The traffic controller cabinet is the large electrical control box which is usually located near one of the poles which support lights at an intersection. The traffic control cabinet usually contains many subsystems that process data and output signals to the traffic signal heads which control the vehicular traffic. Typically the subsystems include power supplies, field input terminals, lube protectors, fuses and the like.  
           [0015]    In one embodiment the emergency vehicular traffic control apparatus includes a deep cycle battery, a charger to charge the battery, a relay for sensing the loss of power from the utility system, the relay including contacts for alternately delivering energy to and from the deep cycle battery, and an inverter for supplying alternating current to the traffic signal control box. The equipment may be mounted adjacent to the control box (also known as the control station or control cabinet) or it may be located remotely.  
           [0016]    Another embodiment of the emergency vehicular traffic control apparatus includes a traffic control station, a fuel cell, a hydrogen supply, a solenoid valve interposed between the hydrogen supply and the fuel cell, the solenoid valve being opened upon the loss of power to the traffic control station, a relay for sensing the loss of power from the utility and an inverter for converting the DC power output from the fuel cell to alternating current power supplied to the traffic control station. The traffic control station then controls the traffic signal.  
           [0017]    A third embodiment of the emergency traffic control apparatus comprises a control station having a logic package for controlling the traffic signal, a relay for sensing the loss of utility power being supplied to the control station, a motor driven air compressor powered from the utility when the utility power is present, a compressed air reservoir for storing the compressed air, a pressure switch interconnected with the reservoir for controlling the motor driven air compressor, and, an air powered turbine generator for generating alternating current power to be supplied to the control station without loss of the utility power to the control station. In this embodiment, namely, the compressed energy storage embodiment, the aforementioned equipment may be located within the traffic control signal supporting pole. This is the pole that supports the traffic lights also known as the signal heads.  
           [0018]    All of the embodiments of the invention optionally include a  
           [0019]    Accordingly, it is an object of the present invention to store energy for controlling traffic signal heads upon loss of electrical energy from the utility.  
           [0020]    It is an object to store energy in a chemical form, namely, in a battery, to supply energy to a signal control cabinet and all the equipment therein upon the loss of utility power.  
           [0021]    It is an object of the present invention to store energy in the form of compressed air. The compressed air is then used to drive a turbine generator to supply energy to the control station having a logic package for controlling the traffic signal.  
           [0022]    It is an object of the present invention to store energy in a hydrogen tank for use in generating DC power from a fuel cell. The DC power from the fuel cell is generated when hydrogen is supplied to one side of the fuel cell upon the loss of electrical energy from the local utility. The DC power supplied by the fuel cell is applied to an inverter wherein alternating current is then supplied to the control station which controls the traffic signal heads.  
           [0023]    Other objects of the invention will be understood when reference is made to the Brief Description of the Drawings, Description of the Invention, and claims which follow hereinbelow. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0024]    [0024]FIG. 1 is a schematic of a battery backup power supply to a control station which implements control signal logic.  
         [0025]    [0025]FIG. 2 is a schematic of a compressed air energy storage system for supplying power to a control station which implements traffic control signal logic.  
         [0026]    [0026]FIG. 3 is a schematic of a fuel cell energy storage system for supplying power to a control station which implements traffic control signal logic.  
         [0027]    [0027]FIG. 4 is a perspective view of a typical traffic control cabinet which houses the control station which implements traffic control system logic.  
         [0028]    [0028]FIG. 5 is a perspective view of a typical signal light pole supporting lights at an intersection with the traffic control cabinet in the background.  
         [0029]    [0029]FIG. 6 is a cross-sectional view taken along the lines  6 - 6  of FIG. 5 illustrating a cabled wire bundle inside the traffic signal pole.  
         [0030]    [0030]FIG. 7 is a cross-sectional view taken along the lines  7 - 7  of FIG. 5 schematically illustrating the motor driven air compressor, air reservoir and air driven turbine generator all mounted within the traffic signal pole. 
     
    
       [0031]    A better understanding will be had when reference is made to the Description of the Invention and claims which follow hereinbelow.  
       DESCRIPTION OF THE INVENTION  
       [0032]    [0032]FIG. 1 is a schematic  100  of a battery  107  used in conjunction with a charger  111  an and inverter  112  to supply power to a traffic control logic system upon loss of utility generated power. Relay  101  senses the existence or nonexistence of power supplied by the utility as represented by reference numeral  105 . Relay  101  may be a solid state relay. Power is supplied  105  by the utility subject to rolling blackouts which may occur in the absence of sufficient generating capacity. Power is normally supplied by the utility at 120 VAC and 60 Hz. Contacts  102  and  103  are normally open contacts of relay  101 . Contact  104  is a normally closed contact of relay  101 . By normally open it is meant that with relay  101  deenergized, contacts  102  and  103  are open and contact  104  is closed. Reference numeral  111  represents a charger which charges a deep cycle marine battery  107  when utility power is unavailable at the point indicated by reference numeral  105 .  
         [0033]    Reference numeral  108  simply indicates a cable supplying power to the positive or cathodic terminal of the battery. Reference numeral  110  schematically indicates a line connected to ground from the anode of the deep cycle marine battery. Reference numeral  112  is an inverter which takes the DC power output across the terminals of the deep cycle marine battery  107  and runs it through a normally closed contact  104  and into inverter  112  which inverts the power from a direct current power to an alternating current power. Alternating current is then supplied to the load  106  as indicated in FIG. 1.  
         [0034]    Transmitter  113  senses the presence of power being supplied by the emergency energy power source. Transmitter  113  transmits a radio signal frequency signal to a police station, an emergency operations center or a police car equipped with a receiving unit. Alternatively, transmitter  113  may send a signal over a wire to a police station or emergency operations center. Arrow  114  indicates the signal transmission to a police station or other governmental entity indicating that power is being supplied by the emergency energy source. This signal to the police or others will alert them to the fact of the power outage enabling them to utilize their resources in the most effective way.  
         [0035]    [0035]FIG. 2 is a schematic  200  of a compressed air energy storage system for supplying alternating current power to a control station which implements traffic signal logic. Utility power is normally present at reference numeral  205  and sensing relay  201  monitors the presence or absence of electric utility power. Relay contacts  203 ,  202  and  210  are associated with sensing relay  201 . Relay contacts  203  and  202  are normally open contacts and relay contact  210  is a normally closed contact. By normally open it is meant that when relay  201  is deenergized contacts  203  and  202  are opened and contact  210  which is normally closed is closed in the absence of power across relay  201 .  
         [0036]    Pressure switch  215  is interconnected with air reservoir  220 . The contact  204  is associated with pressure switch  215  and opens upon the achievement of the pressure set point within the reservoir  220 . When the pressure is below the desired set point within tank  220 , contact  204  is closed. When electrical power of sufficient voltage and current is available at power supply  205 , then contacts  203  and  202  associated with relay  201  are closed. As used herein when it is stated that a contact is associated with a relay or pressure switch it is meant that it is driven by the relay or switch and is integral therewith. In this case the load  206  is a traffic signal control cabinet containing equipment which selectively directs power to the traffic control signal heads. Further, in this condition, the motor  208  may be operated to drive air compressor  207  if the pressure in the reservoir  220  is below the set point of pressure switch  215 . Reference numeral  209  merely signifies the rotation of a shaft which couples the electrically driven motor  208  to the compressor  207 . Reference numeral  216  represents an air supply intake to the compressor and reference numeral  217  indicates an air supply line to the reservoir. Reference numeral  214  is a check valve which is interposed between the compressor  207  and the air storage tank  220  to prevent reverse rotation of the compressor  207  and motor  208 .  
         [0037]    Solenoid valve  219  is interposed between the reservoir  220  and the air driven turbine  213 . Solenoid  218  which controls the valve  219  associated therewith is powered when electrical voltage and current of sufficient magnitude is available at point  205  as is indicated in FIG. 2. When electrical energy of sufficient magnitude is present at  205  the solenoid valve  219  is closed.  
         [0038]    Air line  221  interconnects the storage tank  220  and solenoid valve  219 . Air line  222  interconnects the solenoid valve  219  and turbine  213 . Transmitter  224  senses the presence of power being supplied by the emergency energy power source. Arrow  225  indicates the signal transmission to a police station or other governmental entity indicating that power is being supplied by the emergency energy source. This signal to the police or others will alert them to the fact of the power outage enabling them to utilize their resources in the most effective way.  
         [0039]    Reference numeral  211  signifies the exhaust of the air driven turbine  213 . Reference numeral  223  indicates rotation of a shaft which couples the air driven turbine  213  and a generator  212 . Generator  212  is coupled to the output load  206  when the relay  201  is deenergized. This occurs through normally closed contact  210  as explained previously. Reference may be made to FIG. 7 at this time.  
         [0040]    Referring to FIG. 7 which is a cross-sectional view  700  taken along the line  7 - 7  of FIG. 5 illustrating schematically the motor driven air compressor  207 , the air reservoir  220  and its air driven turbine generator  213 / 212  all mounted within a traffic signal pole  504 . Traffic signal pole  504  may be best viewed in FIG. 5. Most modern cities have done away or are in the process of doing away with traffic signals heads which are supported by wires or metal lines. The new traffic signal poles are much more esthetically pleasing than were the supporting lines. Referring still to FIG. 7 air reservoir  220  is sized to provide enough energy to meet the energy requirement. The more energy required to run the lights during utility power outages, the larger volume  220  needs to be. Reference numeral  704  is a quick disconnect coupling. If a city or municipality desires they may be able to charge the volume  220  from a portable air compressor which may be hauled around behind a pickup truck for instance. In this event the motor  208  and compressor  207  are not necessary because the energy is stored in reservoir  220  by virtue of the mobile air compressor. The municipality crew merely drives around periodically and supplies the air reservoirs  220  with sufficient pressure to operate the turbine motor packages  213 / 212 . This as the advantage of eliminating the motor  208  and compressor  207  from each location. Reference numeral  706  is a vent which is necessary to vent air from the exhaust of the turbine  213 . The vent may also occur naturally through conduit  505  which supports the lights. Conduit  505  necessarily has openings behind signal heads  501 ,  502  and  503  as shown in FIG. 5. These openings are necessary for wiring which drives the signals. Conduit  702  and  703  are air passageways. Junction box  705  works in conjunction with control station  401  which will be discussed hereinbelow. Air supply opening  701  is viewed in FIG. 7 and this is an opening in the pole to allow air to be brought therein for compression by compressor  207 .  
         [0041]    Referring to FIG. 5, a perspective view  500  of a typical signal light pole  504  supporting signal lights or signal heads as they are known at an intersection with the traffic control cabinet  401  in the background. Traffic control cabinet  401  is illustrated best in FIG. 4 and includes PLC or other logic control devices for operating the signals heads  501 ,  502  and  503 . Typically the traffic control cabinet is supported on a cement pad  402 . The traffic control cabinet includes vents  404 ,  405  as best viewed in FIG. 4. FIG. 4 is a perspective view  400  of a typical traffic control cabinet which houses the control station which implements the traffic control system logic. Access is gained to the traffic control cabinet through handle  403 . The energy sources and equipment disclosed herein may be mounted in a box on the top of the traffic control cabinet. The battery backup, and fuel cell embodiments of this invention illustrated in FIGS. 1 and 3 are particularly apt to be mounted on top of the traffic control cabinet  401 . Reference numeral  406  is the box or cabinet which houses the equipment set forth in FIGS.  1 - 4 . The size of the box is dictated by the size of the equipment used such as the battery, hydrogen tank or compressed air storage tank. Interconnections between the box  406  and the control cabinet  401  which contains the signal controls can be easily made by cutting through the top of control cabinet  401 .  
         [0042]    Referring again to FIG. 5 the perspective view  500  of traffic signal light pole, a typically large diameter metal pole  504  is used. The light pole cross bar which supports the lights is indicated in FIG. 5 by reference numeral  505 .  
         [0043]    [0043]FIG. 6 is a cross-sectional view  600  taken along the lines  6 - 6  of FIG. 5 illustrating a wire bundle  602  residing within a cable  601 . Cable  601  is a metal conduit or plastic conduit which is preferably sealed. Reference numeral  603  indicates the available space for the storage of air if so desired. If it is desired to store the air within the pole  504 , it is stored in a way similar to that shown in FIG. 7. Necessarily in FIG. 7 a check valve or other device will be used between the compressor  207  and the storage tank  220 . The check valve would be in air conduit  702 .  
         [0044]    Referring to FIG. 3, a schematic  300  of a fuel cell  309  energy storage system for supplying power to a control station which implements traffic signal control logic. The control station is located in the control cabinet. Sensing relay  301  which monitors the existence or nonexistence of power supplied from the utility. The power supplied from the utility is typically 120 VAC, 60 hertz. Relay contact  302  is a normally opened contact and relay contact is a normally closed contact. In other words, when power exists at  305 , contact  302  of relay  301  is closed and contact  303  of relay  301  is opened. Hydrogen tank  310  is filled with compressed hydrogen which is supplied to the fuel cell upon the discontinuance of power at  305 .  
         [0045]    Valve  312  is open when power is not present at  305 . Air supply  313  is fed into fuel cell  309 . Water is drained  314  from the fuel cell when power is being output at the positive or cathodic terminal of the fuel cell through closed relay contacts  303  to inverter  308  which converts the DC power to AC power which is output on line  304 . Power output in the form of alternating current is supplied to the traffic signal control device  306  (sometimes referred to herein as the control station  306 ). Line  307  merely indicates the electrical connection between the power supply line and the solenoid  311 . When solenoid  311  is energized valve  312  is closed. When solenoid  311  is deenergized valve  312  is open and this allows the passage of hydrogen to the fuel cell. Two thousand 2000 Watt-hours of energy can easily be supplied from a mere four (4) liters of hydrogen at 3000 psi. Obviously a larger volume and lower pressure may be used to supply the fuel cell. The physical constraints of the size of box  406  are the limiting factors in the size of tank  310 .  
         [0046]    Transmitter  315  senses the presence of power being supplied by the emergency energy power source. Arrow  316  indicates the signal transmission to a police station or other governmental entity indicating that power is being supplied by the emergency energy source. This signal to the police or others will alert them to the fact of the power outage enabling them to utilize their resources in the most effective way.  
         [0047]    Those skilled in the art will readily recognize that modifications and changes may be made to the invention as disclosed herein without departing from the spirit and scope of the appended claims.