Embodiments of the invention generally relate to secondary or back-up lighting systems.
Traditional outdoor light applications are designed to widely disperse light over large areas. These outdoor light fixtures are found in parking lots, activity areas like parks and athletic fields, and aligned along streets and sidewalks, and other high traffic areas. Many of these outdoor light fixtures utilize a high intensity discharge (HID) lamp that produces enough illumination to fully light the outdoor areas. A HID lamp is favorable over other light sources, such as fluorescent and incandescent lamps, because HID lamps have greater luminous efficacy.
While highly efficient, a HID lamp must be in a cooled state before it can be activated. Once activated, HID lights must cool down before they can be reactivated. HID lamps take a considerable amount of time to cool down after any use. The cool down period can be in excess of fifteen minutes. When an outdoor light fixture utilizing a HID lamp experiences a power interruption, the area surrounding the light fixture is devoid of light until the HID lamp has cooled and can be re-activated. The absence of light during the required cool down period can leave individuals and property in unsafe situations.
The common practice within the industry to counteract the lack of light during the cool down period is to employ a Quartz Restrike System (“QRS”). A QRS adds an incandescent quartz light source inside the HID lamp housing to provide instant light when power is restored. However, due to the height at which the luminaire housing is mounted, the fact that the optics for the light are optimized for the HID lamp (and not the quartz light source), and the low intensity of the quartz source, not much light reaches the ground below. Therefore, there is a need to provide immediate illumination after a power interruption until the HID lamp has fully cooled and can be reactivated. Additionally, there is a need for this light to adequately illuminate the areas surrounding the outdoor light fixture during the cool down period.
Embodiments of this invention provide a secondary, or back-up, lighting system for light fixtures having a primary light source. The back-up lighting system is configured to mount onto a support structure of the primary light fixture. The back-up lighting system includes a light source and a lens with optical properties. A housing retains the light source and the lens. The back-up lighting system may include a controller that monitors the main power source for the primary light source of the light fixture. The controller activates the light source of the back-up lighting system upon detecting power restoration after a power loss. In some embodiments of this invention, the back-up lighting system may include a secondary power source that powers the back-up lighting system during a loss of power.
Embodiments of this invention provide a back-up lighting system for use as a secondary light source immediately after power restoration following a power loss and before the primary light source can be re-activated. The back-up lighting system may be attached to any suitable light fixture, including, but not limited to, outdoor fixtures such as parking lot, street, and sidewalk lamps. In some embodiments of this invention, the back-up lighting system may include a secondary power source, allowing the back-up lighting system to provide adequate and immediate illumination during power outages.
As shown in
As illustrated in
While back-up lighting systems 10 may be manufactured so that their apertures 14 are sized to fit precisely around a particular support structure 22, it may be preferable to provide a back-up lighting system 10 that can be adapted to fit universally on a variety of different support structures 22. If the aperture 14 of a back-up lighting system 10 is larger than the dimensions of the support structure 22, a gap exists between the support structure 22 and the back-up lighting system 10 when the back-up lighting system 10 is mounted. In some embodiments, the size of the aperture 14 of the back-up lighting system 10 may be adjustable. For example, expandable flanges may be connected to the backside of the components 12 of the back-up lighting system 10. The flanges may be extended or retracted as necessary to eliminate the gap between the backside of the components 12 and the support structure 22.
In other embodiments, a mounting gasket 30 may be used to address the gaps and ensure a secure mount. As shown in
A gasket aperture 37 is defined in the mounting gasket 30. The gasket aperture 37 preferably, but not necessarily, corresponds to the cross-sectional shape of the mounting structure 22 and can also, but does not have to, correspond to the shape of the aperture 14 of the back-up lighting system 10. The back-up lighting system 10 is adapted to receive different mounting gaskets 30 depending on the cross-sectional shape and size of the support structure 22 on which it is intended to be mounted.
The mounting gasket 30 eliminates gaps and prevents the back-up lighting system 10 from shifting while mounted on the support structure 22. However, gaps can still exist when a gasket 30 is positioned when mounting a back-up lighting system 10 having a rectilinear aperture 14 to a support structure 22 with a rectilinear shape. Rectilinear shaped support structures may have rounded corners. The rounding of the corners can vary from 1/16 of an inch to ½ of an inch. The variance among the rounding of the corners would require gaskets 30 to be produced that substantially match the possible ranges. A gasket having dual-durometer properties may be used to solve this problem. The dual durometer gasket 30 has two different compressibilities, a high compressibility at the corner portions 38 and a lower compressibility at the middle portions 39. The gasket 30 can be designed to eliminate gaps formed by the largest possible rounding of the corners, but still be used with the rectilinear support structures having less-rounded corners because of the high compressibility of the corners 38 of the gasket 30. The high compressibility of the corners 38 allows the unneeded material to be displaced, or compressed, by rectilinear support structures 22 having less-rounded corners.
Other means of ensuring a secure fit between the back-up lighting system 10 and the support structure 22 may be used. As shown in
Fins 43 are preferably formed on the outer surface 41 of the housing 40. The fins 43 dissipate heat generated by the light source 60. In order to further assist in the heat dissipation, the housing 40 can be manufactured from aluminum. While aluminum is preferable, the housing 40 may be made from steel, copper, or other various heat-conducive materials.
The housing 40 includes ends 44 and 45 adapted to abut corresponding ends on the opposite component 12 when the back-up lighting system 10 is mounted, as shown in
A wire aperture 49 is preferably positioned along the inner surface 48 of the component 12. The wire aperture 49 provides a pathway for the wiring from the light source 60 to the exterior of the housing. Mounting apertures 50 may also be found along the inner surface 48 of the housing 40, and extend through to the outer surface 41. Fastening means, such as screws, bolts, and the like, may be received by the mounting apertures 50 to mount the back-up lighting system components 12 to the support structure 22. The mounting apertures 50 may be aligned between fins 43 of the housing 40 in order to hide fastening means from view.
The interior 51 of the housing 40 receives a light source 60, lens 70, and an optional sealing gasket 80 (collectively “internal components”). The underside of the housing 40 may be adapted to ensure retention of the internal components in place. For example, as illustrated in
In the embodiment shown in
Any number of LEDs 62 are mounted to a light board 64 substantially shaped to match the shape of the trough 52 of the housing 40 to ensure a good fit within the housing 40. The LEDs 62 may be mounted on various parts of the light board and in any pattern, depending on the optical needs of the back-up lighting system 10. The circuitry of the LEDs may be mounted on the opposite side of the light board 64. Preferably, the circuitry is positioned on the light board 64 to align with the channel 57 of the housing 40 when installed, but it does not have to be. Apertures 66 may be positioned along the light board 64 in alignment with the apertures 56 of the housing 40.
A lens 70 encloses the light source 60 within the housing 40. The lens 70 is preferably formed of a transparent material. Preferably, the transparent material is a polymeric material, such as, but not limited to, polycarbonate, polystyrene, or acrylic. Use of polymeric materials allows the lens 70 to be injection-molded, but other manufacturing methods, such as, but not limited to, machining, stamping, compression-molding, etc., may also be employed. While polymeric materials may be preferred, other clear materials, such as, but not limited to, glass, topaz, sapphire, silicone, apoxy resin, etc. can be used to form the lens 70. It is desirable to use materials that have the ability to withstand exposure to a wide range of temperatures and non-yellowing capabilities with respect to ultraviolet light.
Just as with the light board 64, the lens 70 is preferably shaped to match the shape of the trough 55 to ensure a tight fit within the housing 40. When mounted within the housing 40, the lens 70 provides protection for the electrical components from the surrounding environment. Apertures 76 may be positioned along the lens 70 in alignment with the apertures 56 and 66 of the housing 40 and light board 64, respectively. A sealing gasket 80, substantially tracing the outline of the trough 55, may be placed between the lens 70 and the housing 40 to further weather proof the internal components of the light ring 10. A fastener, such as the screws 82 shown in
While the lens 70 protects the interior of the housing 40, it also controls the light distribution of the light source 60. The optical properties of the lens 70 dictate the distribution of the light emitted from the LEDs. The particular optical properties of the lens are not critical to embodiments of the invention. Rather, the lens 70 may be formed to have any optical properties that impart the desired light distribution(s). One of skill in the art would understand how to impart such properties to the lens 70 to effectuate the desired light distribution. However, by providing optics tailored to a particular application, the back-up lighting system 10 creates a more efficient secondary light distribution that illuminates the needed areas more effectively than the traditional quartz back-up systems discussed above.
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As shown in
In one embodiment, the controller 90 monitors for a temporary loss of power to the primary light source 24. More specifically, the controller 90 monitors for an interruption and the return of the power to the primary light source 24. When a temporary loss of power is sensed, the controller 90 activates the light source 60 of the back-up lighting system 10. Since the power has been restored to the main power source 26, the light sources 60 can be powered by the main power source 26. When there is a dedicated power input line for the back-up lighting system 10, the light sources 60 may be powered by the dedicated power input line, so long as the input line is operable. Upon activation, the back-up lighting system 10 immediately provides full illumination. The controller 90 continues to monitor the power supply and can deactivate the back-up lighting system 10 once enough time has passed to allow the primary light source 24 to cool and reactivate. The controller 90 may also monitor for the complete loss of power when a secondary power source 100 is available. When a loss of power is sensed, the controller 90 activates the back-up lighting system 10, drawing power from the secondary power source 100, to provide light while the primary power source 26 is inoperable. The back-up lighting system 10 will continue to operate until the power is restored to the primary light source 24 (as long as the primary light source has cooled), as is indicated by the controller 90, or until the secondary source 100 is completely depleted.
The combination of the back-up lighting system 10 components leads to a much more desirable secondary light source than one currently supplied within traditional primary light fixtures, especially ones using a QRS system. First, the back-up lighting system 10 may have optics configured specifically for its own light source and need not rely on the optics designed for the primary light source. Second, the back-up lighting system 10 utilizes a light source 60 that produces a greater intensity of light than that of other secondary light systems. The greater intensity leads to a greater amount of light produced. Third, the back-up lighting system 10 is mounted below the primary light source 24, as opposed to within the primary light source 24. As a result, the back-up lighting system 10, and the light it produces, is closer to the ground. The combination of these factors leads to more efficient and effective illumination during periods of inoperability of the primary light fixture 20.
The foregoing has been provided for purposes of illustration of an embodiment of the present invention. For example, the back-up lighting system may be mounted upside down to provide light upwardly to features located above the back-up lighting system. In other embodiments, the lens may be configured to direct light to a very specific location. Modifications and changes may be made to the structures and materials shown in this disclosure without departing from the scope and spirit of the invention.
This application claims the benefit of U.S. provisional application Ser. No. 61/039,969, entitled “LED Ring Light”, filed Mar. 27, 2008, the entire contents of which is hereby incorporated by reference.
Number | Date | Country | |
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61039969 | Mar 2008 | US |