Abstract:
Power over Ethernet power sourcing device is provided inside a light fixture to enable a communications interface and provide electrical power to devices such as cameras, rain sensors, chemical sensors, wireless data uplink units, and other power over Ethernet powered devices. The power over Ethernet system is especially adapted for use in LED street lights and must be able to operate from a wide AC voltage supply range that is typically found in these types of lights.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to street lighting in general and the advantages to be gained by exploiting the&#39;ubiquitous availability of street light supports to carry additional useful, powered equipment such as traffic cameras, air quality monitoring devices and telecommunication transceivers. This invention further relates to light fixtures, preferably light fixtures having solid state lighting (preferably a light-emitting diode light unit (LED)) and, more particularly, to a solid state light device or fixture that includes at least one power over Ethernet (POE) power sourcing device that may be used to source power and provide a data connection to one or more powered devices that may be either internally or externally affixed to the light fixture or located proximate to the light fixture. 
     The light fixture of the present invention is suitable for use in connection with any kind of lighting source, including incandescent bulbs, arc lamps, fluorescent tubes, induction lighting and solid state lighting. The light fixture of the present invention is particularly adapted for use as an outdoor street light fixture. The presently preferred lighting source for use in connection with the present invention is solid state lighting, such as an LED light unit. 
     The term “solid state” is commonly used to refer to light emitted by solid-state electroluminescence, as opposed to incandescent bulbs or fluorescent tubes. LED Solid-State Lighting (SSL) refers to a type of lighting that uses semiconductor light-emitting diodes, organic light emitting diodes, or polymer light-emitting diodes as the source of illumination. 
     Light Emitting Diode (“LED”) light units are an increasingly popular form of solid state lighting. LED light units (LED bulbs) offer many advantages over incandescent lighting, including lower energy consumption, longer life and ease of control. As the cost of LED light units are reduced, LED light units are being used in more diverse applications, including indoor and outdoor illumination. Solid-state lighting is often used in traffic lights and is quickly becoming the light engine choice for development in modern vehicle lights, street lights, tunnel lights, parking lot lights, indoor parking garages, area flood lights, building exteriors, bill board signage, and indoor commercial and residential lighting. 
     A light fixture includes a connection to an external power supply. When the light fixture is a table lamp, the connection is typically provided by a common plug plugged into a electrical wall socket or power strip and the housing of the light fixture has its own base upon which to rest. However, when the light fixture is an outdoor light fixture, such as a street light, mounted upon a utility pole or other elevated support, significant costs are incurred in providing a connection between the external power supply and the light fixture. Typically, a wired connection is made through the inside of the utility pole and into the light fixture through the light fixture mount to a terminal block inside the light fixture. This arrangement keeps the wiring for the light from being exposed to the elements. When the pole is made of wood, however, the wiring is external on the pole side, but enters the light fixture at a weatherproof connector or port in the light fixture housing before connecting to the terminal block. 
     For street lighting applications, it is desirable to mount additional types of powered devices to the light, mounting arm between the light and pole, utility pole or other lighting structures to provide any one of numerous complimentary services or capabilities. This placement takes advantage of the high vantage point offered by these structures, which are densely scattered throughout populated areas and are common even in relatively unpopulated areas. 
     It is even more desirable for such powered devices to be adapted in such a manner as to be able to send and receive digital data, thereby enabling remote control of the powered device and for the remote device to transmit data, such as a video feed via a wireless, hard-wired or fiber optic Internet haul connection to a central communication and control computer where the data can be put to further useful purpose. Such additional powered devices include, but are not limited to, control units for the lights, control units for other powered devices, computer networking devices, network switches, network routers, security cameras, traffic cameras, video cameras, still-photography cameras, other surveillance equipment, rain sensors, air quality sensors, chemical sensors, radiation sensors, light sensors, temperature sensors, wind sensors, humidity sensors, air pressure sensors, wireless access points, wireless data uplink units, wireless data receivers, telecommunication transmitters and receivers, two way radios, VOIP telephones, energy consumption meters, heating devices, cooling devices, fans, heat sinks, memory devices, or any other powered device desired and adaptable for attachment to a light fixture, such as a street light. 
     Until now, the usefulness of attaching such desired powered devices to utility poles has been tempered by the additional costs associated with installing a separate and metered connection for such powered devices to an external power source. Such separate power connections currently require additional wiring installed by a licensed electrician and attachment to the pole. Even for a small city or town, the cost of adding additional power supply hook-ups, with or without meters, to the tops of hundreds of utility poles scattered over hundreds of square miles is prohibitive. Similarly, providing a digital data back haul communication link with such powered devices can be even more expensive. 
     Additionally, the installation, repair, service, maintenance, upgrading or replacement of such powered devices is an added burden when the powered devices are hard-wired to an external power supply. For example, where the effort has been made to install an air quality sensor atop a utility pole, even upgrading the sensor can be burdensome as it would typically require someone with an electrical and/or telecommunications background to travel to each far-flung device to disconnect the hard-wired power supply and telecommunications link and reconnect the new, upgraded sensor. 
     There exists a need for an improved means for providing power and digital data communication connections to powered devices atop utility poles. 
     There also exists a need for simplifying the ability to easily interchange or replace powered devices that are situated atop utility poles. There also exists a need for reducing initial installation costs associated with such powered devices. 
     There also exists a need for remotely monitoring the status and power usage of powered devices installed in outdoor locations. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is a light fixture, such as a light fixture suitable for installation atop a utility pole or other elevated vantage point, having at least one power over Ethernet power sourcing device for use in providing a power source to one or more internally or externally affixed powered devices or proximately located powered devices. The power over Ethernet power sourcing device is housed within the light fixture, preferably with a separate power input connection to the terminal block hosting the external input power source of the light fixture, the light unit or units (or the light power supply drivers) having their own separate power input connection to the common input power terminal block. The power over Ethernet power sourcing device is preferably a separate power and data connection source for powered devices distinct from the power source for the light units of the light fixture, the power over Ethernet power sourcing device having its own, independent electrical circuit apart from the circuit or circuits providing electricity to the light units. Preferably, the light fixture houses a solid state or LED light unit. 
     The power over Ethernet power sourcing device provides one or more, preferably a plurality of ports or peripheral bus receptacles, such as USB ports, RJ45 ports, or multi-pin ports, each of which is adapted to provide power to and data communication to and among a number of powered devices, specifically, a wireless telecommunications device for transmitting data, a network switch, and a microcontroller unit for monitoring and controlling the voltage and current of each peripheral bus receptacle. One or more peripheral powered devices, such as a digital camera, wireless access point, light control unit (such as an LED driver), or other desired sensors may then be easily connected, disconnected and exchanged through use of the peripheral bus receptacles, and each of the powered devices may in turn be remotely controlled or monitored by or transmit data to a central communications and control computer or server, such as a cloud server. 
     The power over Ethernet power sourcing device is mounted inside the light fixture. Preferably, both the power over Ethernet power sourcing device of a light fixture and the light units of the light fixture are both independently connected to a common input from an external power source. The power over Ethernet power sourcing device is connected to a separate terminal of the terminal block connected to the external power source. The power over Ethernet power sourcing device is able to host powered devices other than the light engine (light control unit or LED driver), providing a separate power supply source apart from the light units for such powered devices. The power over Ethernet power sourcing device also supports data transfer and reception via either a wireless, hard-wired or fiber optic Internet interface. Similarly, it provides support for a separate energy consumption and power on/of status remote monitoring device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The particular features and advantages of the invention as well as other objects will become apparent from the following description taken in connection with the accompanying drawings in which: 
         FIG. 1  is a side perspective illustration of a light fixture of an embodiment of the present invention. 
         FIG. 2  is a bottom perspective illustration of a light fixture of an embodiment of the present invention with an access panel removed. 
         FIG. 3  is a block diagram of a power over Ethernet system of the light fixture of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     A light fixture  10  according to the present invention is illustrated in  FIGS. 1 and 2 . Light fixture  10  has a weatherproof outer housing or shell, such as die-cast aluminum housing  13  or composite injection molded material, about the internal components (not shown in  FIG. 1 ) of the light fixture  10 . The outer housing  13  further comprises one or more globes or optical lenses  14  for allowing light out of the outer housing  13  or, in the alternative, one or more accessible light sockets or receptacles (not shown) for receiving direct attachment of and providing power to one or more light units  12  (See  FIG. 2 ). The light fixture  10  further comprises a mounting means or mounting portion  15  for attaching the light fixture  10  to a utility pole or other support structure  16 . The outer housing  13  and globes or optical lenses  14  may be formed from any suitable materials which are well known in the art, as are the various types of mounts  15  or mounting means. 
     In the embodiment shown in  FIG. 1 , outer housing  13  further comprises one or more external peripheral bus receptacles  20  supplying both power and data communication to a powered device  30  located outside of the housing  13 . External peripheral bus receptacles  20  may be of any known type or kind suitable for a particular powered device  30 , such as a Universal Serial Bus (USB) port  22 , FireWire port (not shown), Serial ATA port (not shown), or RJ45 port (not shown). In the embodiment illustrated in  FIG. 1 , the plurality of peripheral bus receptacles  20  are illustrated as one or more USB ports  22  and one or more direct power over Ethernet adapter ports  24 . Each direct power over Ethernet adapter port  24  comprises a POE data receptacle  25  paired with a corresponding POE power receptacle  26 . Alternatively, when a powered device is a POE enabled powered device, direct power over Ethernet adapter ports  24  may simply comprise a POE data receptacle  25 . 
     As shown in  FIG. 2 , the light fixture  10  further comprises a power over Ethernet power sourcing device  33  within the housing  13 . In one preferred embodiment, the power over Ethernet power sourcing device  33  comprises a POE switch or endspan at least meeting the IEEE 802.2 at standard, that is, a network switch that has power over Ethernet injection built-in. Alternatively, in another preferred embodiment, the power over Ethernet power sourcing device  33  may comprise a midspan or POE injector. The power over Ethernet power sourcing device  33  is responsible for querying connected powered devices  30  to determine the need for power to be applied and to control the amount of power being pulled so that applicable limits are not exceeded. 
     The light fixture  10  may further comprise one or more internal peripheral bus receptacles  40  within the housing  13 , such as USB ports  22  and/or one or more direct power over Ethernet adapter ports  24 . The power over Ethernet power sourcing device  33  is operatively connected, such as by appropriate cabling or other connections (not shown) to the internal peripheral bus receptacles  40  and the external peripheral bus receptacles  20 . Internal peripheral bus receptacles  40  located within the housing  13  and external peripheral bus receptacles  20  on the outer housing  13  of the light fixture  10  allow the creation of a local area network or Ethernet within the light fixture  10  by allowing for one or more powered devices  30 , such as wireless telecommunications device  36  (operating under any suitable standard for wireless communication of high speed data, including 3G wireless, 4G wireless (or LTE) or any suitable standard), microcontroller unit  37 , and a network switch  38  to be operatively interconnected, such as by appropriate connecting cables  21 , such as the illustrated data cable  31  and power cable  32 , to the power over Ethernet power sourcing device  33  through such peripheral bus receptacles  20 ,  40 . 
     Alternatively, internal peripheral bus receptacles  40  may also comprise fixed connections between the power over Ethernet power sourcing device  33  and one or more of the more desirable powered devices  30 , such as a wireless telecommunications device  36 , camera (not shown), or a light control unit  39  for controlling the operation of the light units  12  of the light fixture  10 . 
     In another embodiment, one or more of the powered devices  30  may comprise POE-enabled powered devices that may be directly attached by appropriate CAT-5 cable connections to the power over Ethernet power sourcing device  33  at a power over Ethernet adapter port  24  of the appropriate type. 
     The specific powered devices  30  suitable for attachment to the light fixture  10  may be any peripheral or controller device desired which may now or in the future exist which may be operated through a peripheral bus receptacle  20  or  40  or which require another form of connection for both a power source and a data communication link. Powered devices  30  may comprise any electronic or electrical device requiring a source of power or power and data communication. Powered devices  30  suitable for the present invention may include, but are not limited to, control units for the lights, control units for other powered devices, computer networking devices, network switches, network routers, security cameras, traffic cameras, video cameras, still-photography cameras, other surveillance equipment, rain sensors, air quality sensors, chemical sensors, radiation sensors, light sensors, temperature sensors, wind sensors, humidity sensors, air pressure sensors, wireless access points, wireless data uplink units, wireless data receivers, telecommunication transmitters and receivers, two way radios, VOIP telephones, energy consumption meters, heating devices, cooling devices, fans, heat sinks, memory devices, or any other powered device desired and adaptable for attachment to a light fixture  10 , such as a street light. 
     When the light fixture  10  is intended for outdoor use, the powered devices  30  and their connecting cables  21  to the external peripheral bus receptacles  20  will have to be waterproof and otherwise sturdy and rugged enough to function when exposed to the elements and temperature extremes without undue need for repair. Additional weather protection may be achieved through the strategic placement of peripheral bus receptacles  20  on the lower surfaces  17  of the outer housing  13  or locating the peripheral bus receptacles  20  in covered or uncovered recesses (not shown) formed in the outer housing  13 . Of course the best weather protection for powered devices  30  is to locate them within the housing  13 , such as the wireless telecommunications device  36  shown in  FIG. 2 . The opening or compartment  34  in the housing  13  shown in  FIG. 2  would be covered with a releasably secured detachable access panel (not shown). One of the principal advantages of the present invention, however, is the ease and convenience that a light fixture according to the present invention affords for connecting and disconnecting external powered devices  30  to the external peripheral bus receptacles  20 . 
     Returning to  FIG. 1 , releasably secured detachable protrusions, shells or casings  27  may be provided within which to house powered devices  30  or portions thereof, such as antennas or sensors (not shown). Such casings  27  provide additional weatherproofing and protection for the powered devices  30  which they surround and may be prefabricated in different shapes to contain and conceal different types, shapes and sizes of powered devices  30 . 
     The outer housing  13  may alternately further comprise one or more fastening means  28  for demountably affixing and securing powered devices  30 , such as the illustrated keyhole mount  51 , threaded shaft  52 , or other common alternative fastening means such as bolts, holes for receiving bolts, clamps, latches, slots, grooves, couplings, hooks, pins, cotter pins, screws or other joints specifically fashioned for holding a specific powered device  30 , such as the female connection port  53  into which the male end (not shown) of casing  27  is releasably affixed. Any suitable fastening means  28  may be provided to accommodate the desired powered device or devices  30 , and the placement and orientation of the fastening means  28  about the outer housing  30  may be designed differently to fulfill different needs and intended uses. Of course, a powered device  30  may be independently affixed to the support structure  16  and only operatively connected to an external peripheral bus receptacle  20  by appropriate cabling (not shown). 
     As shown in  FIG. 2 , the light fixture  10  is also operatively connected to receive power from an external power source  11  in any of the well known manners, such as the illustrated electrical line  18  entering the light fixture  10  via an access opening  42  in the mount  15 . A terminal block  44  having multiple electrical output terminals (not shown) inside the housing  10  is adapted to be connected to the electrical line  18 . Light units  12 , preferably LED light units, are powered by connection to the terminal block  44  at a first electrical output terminal. Similarly, power is supplied to the power over Ethernet power sourcing device  33  by an electrical connection to the terminal block  44 , preferably to a second electrical output terminal of the terminal block  44  so that the light units  12  and power over Ethernet power sourcing device  33  are run on separate electrical circuits originating at the terminal block  44  of the light fixture  10 . 
     In an alternate embodiment, power source  11  may comprise a built-in solar power unit or batteries (not shown). Batteries may also be installed as a secondary or back-up power supply configured to engage and power the light fixture only in the event of the failure of the primary external power source  11 . 
     The block diagram of  FIG. 3  illustrates a schematic of one embodiment of the present invention. In the embodiment illustrated in  FIG. 3 , the power over Ethernet power sourcing device  33  is a midspan injector operatively connected in any conventional method to an electrical terminal block  44  (and thus to the external power source  11 ), such as through AC to DC switching power supply  61 , which provides an output of 48V that is used to power the power over Ethernet power sourcing device  33 . The AC to DC switching power supply  61  may be sized as desired to power the intended powered devices (not shown in  FIG. 3 ). 
     It is also preferable for the AC to DC switching power supply  61  to be operatively connected to a DC to DC converter  63  for local point of load within the system. The DC to DC converter  63  converts the 48V input and supplies a low voltage power output for powering low voltage powered devices such as the Ethernet switch  65  and microcontroller unit  37 . 
     In other alternate embodiments, an AC/AC inverter power supply, or an AC receptacle may be installed in the light fixture to provide power to a powered device  30  of the type requiring an AC power input source. 
     An Ethernet switch  65 , such as a five-port 10/100 Mb/s Ethernet switch, functions as a communication gateway between the different powered devices  30 , providing a communications interface between the various powered devices  30  using standard Ethernet protocols. At least one port of the Ethernet switch  65  is connected to the microcontroller unit  37  which is used to monitor and control the power which is supplied to the different peripheral bus receptacles  20 ,  40 . A serial interface between the microcontroller unit  37  and the power over Ethernet power sourcing device  33  allows the microcontroller unit  37  to access and control the voltage and current channeled to each port and the ability to separately turn on and off one or more of the peripheral bus receptacles  20 ,  40  or any other direct connections to the power over Ethernet power sourcing device  33 . 
     A plurality of ports of the Ethernet switch  65  are connected to the power over Ethernet power sourcing device  33 , which in turn provides a data connection and a power connection to a plurality of direct POE ports  24  or peripheral bus receptacles  20 ,  40 . As described above, direct POE ports  24  provide data connection and power connection to additional powered devices  30  or to internal peripheral bus receptacles  40  and external peripheral bus receptacles  20 . 
     As better illustrated in  FIGS. 1 and 2 , the power over Ethernet power sourcing device  33  provides one or more, preferably a plurality of peripheral bus receptacles  20 , 40 , such as USB ports, each of which is adapted to provide power to and data communication among a number of powered devices. Specifically, at a minimum, a light fixture  10  according to the present invention comprises a power over Ethernet power sourcing device  33  operatively connected to provide a power connection and a data connection to a wireless, hard-wired or fiber optic telecommunications device  36 , a microcontroller unit  37  for monitoring and controlling the voltage and current of each POE port  24  and/or peripheral bus receptacles  20 ,  40 , and a light control unit  39  for controlling the light units  12  of the light fixture  10 . The telecommunications device  36  transmits data and provides a connection between the local area network or Ethernet of the powered devices  30  of the light fixture  10  and a global computer information network, such as the Internet. Additionally, one or more peripheral powered devices  30 , such as a digital camera, wireless access point, cooling unit, or other desired sensors may then be easily connected, disconnected and exchanged through use of the peripheral bus receptacles, and each of the powered devices may in turn be remotely controlled by and return data to a wirelessly connected central communication and control computer (not shown) through the communications link provided by the wireless telecommunications device  36 . 
     In an alternate embodiment, the telecommunications device  36  may have only a data connection from the power over Ethernet power sourcing device  33  and have a power input connection (not shown) for receiving power that may be connected to either the power over Ethernet power sourcing device  33  or to an electrical output terminal (not shown) of the terminal block  44 . In other words, the telecommunications device  36  may have an independent power connection separate from the power over Ethernet power sourcing device  33 , but still be connected to the local area network of the light fixture  10 . Such a configuration may be warranted in certain situations, such as where the telecommunications device  36  is of a type requiring greater power input than may be supplied through a power over Ethernet power sourcing device  33 . Similarly, other types of powered devices  30  may be operatively connected to the local area network of the light fixture  10  but require independent electrical power connections. Such powered devices  30  would be operable through the local area network, but not supplied powered through the power over Ethernet power sourcing device  33 . 
     In an alternate embodiment, a powered device  30  may further comprises a metrology chip device (not shown) operatively interconnected to another of the powered devices  30  connected to the power over Ethernet power sourcing device  33 . A metrology chip device may be tasked to monitor and report power status data for a powered device  30  back to the central communications and control computer. Such a metrology chip device is especially useful for determining the operational status of each powered device  30  and would enhance the ability to make quick and efficient repairs by providing knowledge regarding the nature of issues prior to physically visiting the light fixture  10 , thereby providing a cost savings over light fixtures  10  having un-monitored powered devices  30 . 
     The input and output power of the power over Ethernet power sourcing device  33  and each of the powered devices  30  and be remotely monitored. It will be useful for the owner of the attached powered devices  30  to be notified of a power failure or malfunction of the device, so that proper restoration can be put into effect. 
     Although this invention has been disclosed and described in its preferred forms with a certain degree of particularity, it is understood that the present disclosure of the preferred forms is only by way of example and that numerous changes in the details of operation and in the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed.