Lighting system with customized intensity and profile

Abstract

A lighting and energy conservation system for low temperature applications includes LEDs as a light source. The LEDs are provided in a modular LED light fixture. The fixture includes a frame supporting a reflector having a plurality of elongated channels. Mounting strips are removably installed in each of the elongated channels, and LEDs are mounted on each of the mounting strips. A separate power control device is associated with each of the mounting strips, so that a total light output intensity and profile of the fixture can be individually customized by selectively adjusting the power control device for each of the mounting strips.

Claims

1. A light fixture, comprising: a frame; a plurality of mounting strips disposed on the frame, each mounting strip having a quick-disconnect connector; a plurality of LEDs mounted on each of the mounting strips; and a power control device associated with the mounting strips, wherein the power control device is configured to selectively vary an amount of power applied to the mounting strips, and wherein a total light output intensity and profile of the fixture can be customized by selectively adjusting the power control device for the mounting strips and by changing the mounting strips using the quick-disconnect connector; wherein the mounting strips further comprise an intermediate portion and opposite end portions; wherein at least one of the end portions includes the quick-disconnect connector and includes a replaceable LED driver; wherein the opposite end portions are fixed to the light fixture; and wherein the intermediate portion is removably disposed on the frame.

2. The light fixture of claim 1, wherein at least one of the end portions includes the quick-disconnect connector and includes the replaceable LED driver, and wherein the quick-disconnect connector electrically couples the intermediate portion to the replaceable LED driver.

3. The light fixture of claim 2, wherein the replaceable LED driver is coupled to the power control device.

4. The light fixture of claim 1, wherein the frame comprises a reflector having a plurality of elongated channels, wherein the elongated channels include a first angled sidewall, a second angled sidewall, and a flat upper wall, wherein the mounting strips are coupled to the flat upper walls of the plurality of elongated channels.

5. The light fixture of claim 1, wherein the power control device associated with the mounting strips includes at least three positions corresponding to at least three different lighting intensity levels.

6. The light fixture of claim 1, further comprising: a motion sensor coupled to the power control device, wherein detected motion causes the power control device to change states.

7. A method comprising: providing a preassembled light fixture comprising an open frame and a plurality of mounting strips, a plurality of LEDs mounted on each of the lighting strips, and a power control device associated with the mounting strips, wherein the power control device is configured to selectively vary an amount of power applied to the mounting strips; and changing the total light output intensity and profile of the light fixture by selectively adjusting the power control device for each of the mounting strips; wherein each of the plurality of mounting strips includes an intermediate portion and opposite end portions; wherein the opposite end portions are fixed to the preassembled light fixture; and wherein the intermediate portion is removably disposed on the open frame.

8. The method of claim 7, further comprising: selectively interchanging a mounting strip on the open frame with a different mounting strip utilizing a quick-disconnect connector of the mounting strip, wherein the quick-disconnect connector connects the mounting strip to the power control device, wherein the mounting strips include at least one end portion having the quick-disconnect connector, and wherein the different mounting strip has at least one of LEDs with different light emitting properties or different lenses associated with the LEDs.

9. The method of claim 7, wherein selectively adjusting the power control device comprises setting at least two mounting strips to one of at least three different lighting levels.

10. The method of claim 9, further comprising: receiving an indication of motion near the lighting fixture from a motion sensor; and changing at least one of the different lighting levels in response to the received indication.

11. A light fixture, comprising: an open frame supporting a plurality of elongated reflective channels; a mounting strip disposed within at least one of the elongated reflective channels; a plurality of LEDs on the mounting strip; a first quick-disconnect connector releasably coupling a driver to a power source; and a second quick-disconnect connector releasably coupling the mounting strip and the driver, the second quick-disconnect connector configured to provide power from the driver, which is received from the power source via the first quick-disconnect connector, to the mounting strip, wherein the total light output intensity and profile of the fixture can be customized; wherein the first quick-disconnect connector and the second quick-disconnect connector cooperatively facilitate replacing the driver without requiring the removal of the mounting strip; wherein the light fixture is configured to allow for the removal of the mounting strip using the second quick-disconnect connector; wherein the light fixture is configured to accept a different mounting strip having different light properties using the second quick-disconnect connector; wherein the mounting strip includes an intermediate portion and opposite end portions; wherein the opposite end portions are fixed to the light fixture; and wherein the intermediate portion is removably disposed on the open frame.

12. The light fixture of claim 11, wherein the driver is mounted to one of the opposite end portions of the mounting strip using a tool-less connector which allows for tool-less replacement of the driver.

13. The light fixture of claim 11, further comprising at least one power control device coupled to the driver.

14. The light fixture of claim 13, further comprising processing electronics configured to change a setting of the power control devices in response to a signal received from at least one of communications electronics and a motion sensor.

15. The light fixture of claim 13, wherein the power control device controls light output for a plurality of mounting strips including a plurality of LEDs.

16. The light fixture of claim 13, wherein the power control device controls light output for a single mounting strip and plurality of LEDs on the mounting strip.

17. The light fixture of claim 11, wherein the open frame comprises a reflector having a plurality of elongated channels, wherein the elongated channels include a first angled sidewall, a second angled sidewall, and a flat upper wall, wherein the mounting strips are coupled to the flat upper walls of the plurality of elongated channels.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1a-1b are schematic images of perspective views of a top side of a modular LED light fixture for a lighting and energy conservation system for low temperature applications according to an exemplary embodiment.

(2) FIG. 2 is a schematic image of a perspective view of a bottom side of a modular LED light fixture for a lighting and energy conservation system for low temperature applications according to an exemplary embodiment.

(3) FIG. 3 is a schematic image of another perspective view of a top side of a modular LED light fixture for a lighting and energy conservation system for low temperature applications according to an exemplary embodiment.

(4) FIG. 4 is a schematic image of a perspective view of an LED mounting strip with connector, driver, multi-position power control device, and power supply connector.

(5) FIG. 5 is a schematic image of a perspective view of a portion of an LED mounting strip, with lenses disposed over the LEDs and various quick-connect devices to mount the lenses to the mounting strip of a modular LED light fixture according to an exemplary embodiment.

(6) FIG. 6 is a schematic image of a perspective view of one lens for directing a profile of light from an LED on an LED mounting strip of a modular LED light fixture according to an exemplary embodiment.

(7) FIG. 7 is a schematic image of perspective views of more lenses for directing different profiles of light from an LED on an LED mounting strip of a modular LED light fixture according to an exemplary embodiment.

(8) FIG. 8 is a schematic image of perspective views of yet more lenses for directing different profiles of light from an LED on an LED mounting strip of a modular LED light fixture according to an exemplary embodiment.

DETAILED DESCRIPTION

(9) Referring to the FIGURES, a lighting and energy conservation system 10 for a low temperature storage area is shown according to an exemplary embodiment. The system includes light emitting diodes (LEDs) as a source of light because LEDs operate more efficiently in low temperature environments, than conventional HID and fluorescent lighting fixtures. The LED light source is provided in a modular LED light fixture having a relatively instantaneous or rapid illumination response time which overcomes the disadvantages of the conventional HID and fluorescent lighting fixtures that require a relatively prolonged initiation and warm-up time before the light level reaches the normal intensity. Accordingly, facility operators may be less inclined to leave such fixtures “on” all the time, even when the area is unoccupied, because there is no longer a significant delay or wait-time for illumination to occur upon turning on the lights. The relatively instant-on nature of the modular LED light fixture to provide full brightness allows the light fixtures to be turned-off when access to the freezer is not desired, thus enhancing efficiency by conserving energy that would otherwise be used by the light fixture, and reducing or eliminating the heat contribution to the freezer from the light fixtures, that must otherwise be overcome by the refrigeration system.

(10) Referring further to the FIGURES, a modular LED light fixture 12 for a lighting and energy conservation system 10 for a low temperature storage area is shown according to an exemplary embodiment. The modular LED light fixture 12 is intended to provide an energy efficient lighting solution for low-temperature applications (such as cold storage rooms, freezers and the like). The modular LED light fixture 12 is shown to include a frame 20 (shown by way of example as an I-beam type frame having a spine 22 and generally perpendicular raceways 24 disposed at opposite ends of the spine 22) supporting one or more reflectors 26 having elongated channel(s) 28. Mounting strips 30 are removably installed in each of the elongated channels 28, and LEDs 32 are mounted on each of the mounting strips 30. Interchangeable lenses 34 are provided over the LEDs 32 and are removably coupled to the mounting strip 30 by a quick-connect device 36. A separate multi-position power control device 40 is associated with each of the mounting strips 30, so that a total light output intensity and profile of the fixture 12 can be individually customized by any one or more of: interchanging lenses 34 on the LEDs 32, interchanging mounting strips 30 within the elongated channels 28, and selectively adjusting the multi-position power control device 40 for each of the mounting strips 30. Although particular lens types and quick-connect devices are shown by way of example in FIGS. 5-8, any of a wide variety of lenses having other optical properties, and other types of quick-connect devices for mounting the lens 34 over the LEDs 32 and to the mounting strips 30 may be provided. Further, interchangeable “lens strips” that covers multiple LEDs may be provided for use with the LEDs and mounting strips. In addition, the modular fixture for low temperature applications may be equipped (or operably associated) with sensors, such as occupancy sensors (e.g. motion, infrared, etc.) that are operable to turn the fixture on/off depending upon occupancy within the low temperature space. Further, the modular fixture for low temperature applications may be equipped (or operably associated) with radio frequency communication devices configured to communicate with a master control device to control operation of the fixture and communicate an operating status of the fixture to the control device. All such variations are intended to be within the scope of this disclosure.

(11) Referring to FIGS. 1a, 1b, and 3, a structure for a modular LED light fixture intended for use in low temperature applications is shown according to an exemplary embodiment. Such low temperature applications are intended to include cold storage facilities (e.g. rooms, warehouses, etc.) having a low temperature space for storage of cold (e.g. refrigerated, frozen, etc.) products, such as food products therein. The fixture includes a frame 20 (shown for example as an I-beam type frame having a central spine portion 22 with oppositely disposed, substantially perpendicular, end portions shown as raceways 24. The spine portion 22 is shown to include mounting structure for certain components of the fixture. For example, a power supply 14 has quick-connect plugs 16 and is mounted using threaded connectors (although the mounting may be accomplished using snap-fit or frictional/interference type connections). The end portions or raceways 24 may include hardware 18 for mounting, suspending or otherwise installing the fixtures 12 within a low temperature space. The end portions or raceways 22 are also shown to support any number of a plurality of reflective channels 28 to suit the light output intensity requirements for a particular low temperature lighting application. For example, the number of reflective channels may be two, four, six, eight, or other suitable number of reflective channels (shown for example as four reflective channels 28 in FIGS. 1a, 1b, and 3). The frame is shown to be a generally “open” type frame having an exposed surface along the top side of the reflectors and the frame to permit rapid and efficient convective transfer of heat conducted from the LEDs 32 and through the mounting strips 30 and reflectors to the surrounding low temperature space. The bottom side of the reflective channels 28 (i.e. the side adjacent to the LEDs) may be provided with a reflective coating to enhance the reflection and dispersion of light from the LEDs. Such a coating may be a white thermosetting powder coating of a type described in U.S. patent application Ser. No. 12/748,323 titled “Reflector with Coating for a Fluorescent Light Fixture” filed on Mar. 26, 2010, the disclosure of which is hereby incorporated by reference in its entirety. Further, the top side of the reflective channels 28 and frame 20 may be provided with a high emissivity coating, in order to enhance radiative heat transfer away from the fixture 12 to the low temperature space. According to one embodiment, the fixture 12 including the frame 20 and reflective channels 28 is suitable for use with fluorescent light bulbs as a fluorescent light fixture, and may be retrofit with the LED components described herein to create the modular LED light fixture for low-temperature applications.

(12) Referring to FIGS. 2 and 4, the components of the modular LED light fixture 12 for low temperature applications are shown according to an exemplary embodiment. The fixture 12 is shown to include a plurality of elongated reflective channels 28 (shown for example as four reflective channels). A plurality of LED mounting strips 30 (shown for example as four LED mounting strips) are mounted or otherwise disposed within the reflective channels 28, and containing a plurality of LEDs 32 (e.g. white LEDs, etc.) incrementally spaced and mounted therealong for providing a source of light output for the fixture 12. According to the illustrated embodiment, the LED mounting strips 30 and the reflective channels 28 have approximately the same length and one LED mounting strip 30 is provided in each reflective channel 28, however, other combination of mounting strips and reflective channels may be used in alternative embodiments. The mounting strips 30 are removable coupled within each channel 28 so that the mounting strips 30 may be quickly and easily exchanged or replaced to permit individually customizing the fixture 12 for a particular application. According to the illustrated embodiment, the strips 30 are mounted at each end to the reflector 26 and/or end portion 24 of the frame 20 using suitable connectors (e.g. threaded connectors, etc.), however, the strips may be mounted using snap-fit, sliding, or interference type connection to provide “tool-less” modular interchangeability of the mounting strips. According to a preferred embodiment, at least a portion of the mounting strips 30 are in contact with the reflector 26 in order to provide a conductive heat transfer path from the LEDs to the body of the reflectors 26 for transfer of heat away from the reflectors 26 and the fixture 12.

(13) Referring further to FIGS. 2 and 4, the mounting strips 30 are also shown to include drivers 42 mounted thereon for driving the LEDs 32. As shown by way of example in FIG. 4, the drivers 42 are coupled to the LED mounting strips using a connector 44, such as a quick-disconnect type connector to facilitate easy and rapid replacement of the drivers 42 and switches 40 if necessary, without having to remove and/or replace the mounting strip 30 with LEDs and lenses (e.g. as a time and cost-savings feature). The drivers 42 are also mounted for quick and easy replacement, such as by using suitable connectors (e.g. threaded connectors, etc.), however, the drivers may be mounted using snap-fit, sliding, or interference type connection to provide “tool-less” replacement of the drivers. The drivers are also shown to receive power (e.g. 24 VDC, etc.) from a power source via a hard wired connector that connects to the driver using a quick-disconnect type of connector 46. The multi-position power control device 40 is shown mounted on (or otherwise incorporated with) the driver 42 and permits adjustment of the light output from the LEDs on the associated LED mounting strip 30. The multi-position power control device 40 may include a four-position switch to fine tune the light output intensity level (e.g. 3.75 percent incrementally until about 30%). The multi-position power control device 40 may be associated with a single LED mounting strip 30 (as shown in FIG. 4) to permit light output adjustment at a mounting strip level within each fixture 12, or a single multi-position power control device may be associated with all mounting strips within the fixture. According to one embodiment, multi-position power control device 40 uses pulse width modulation, so that the adjustment will not unnecessarily consume (e.g. waste, etc.) energy. The four-position switch is also intended to improve the lifetime of the fixture without wasting energy. Referring further to FIG. 4, the mounting strips 30 are shown as being configured in a substantially symmetric manner, such that an intermediate portion contains the LEDs and lenses, and end portions each include the multi-position power control device 40, the driver 42, the driver connectors 44 and the quick-disconnect 24 VDC power connectors 46. The symmetry of the mounting strip components is intended to enhance production and minimize assembly errors by permitting the strip to be installed in either orientation and yet still be entirely functional. The modularity of the mounting strips 30 with quick-disconnect end portions with the driver components is also intended to permit replacement of one driver with another (e.g. different) driver, such as a dimmable driver or the like, to suit other applications, such as applications where a dimmable light fixture is desirable.

(14) The LED mounting strips 30 are further shown to include lenses 34 disposed over each LED 32 and coupled to the mounting strip 30 by a quick-connect device or mechanism for rapid modular interchangeability of lenses having different optical characteristics to permit individually customizing the fixture to suit the light output profile requirements of a particular application. The ability to customize the fixture with lenses having any one or more (e.g. mix, match, etc.) of different optical characteristics provides a degree of modularity to the fixture that is intended to produce focused, high performance, energy efficient lighting in low temperature applications. In order to support manufacturing and maintenance (or retrofit) operations, the LED mounting strips 30 may be provided with various standard patterns of lens types that have been evaluated and tested to provide desired light output profiles, so that customization may be provided on a ‘macro’ level by replacing strips or adding additional strips and reflectors to the frame, or may be provided on a ‘micro’ level by interchanging lenses individually (or in groups, etc.).

(15) Referring to FIG. 5, the lenses are shown to be coupled to the LED mounting strips using any one of a plurality of quick-connect devices 36, according to an exemplary embodiment. According to a first embodiment, the lenses 34 are shown to attach to the LED mounting strip using a twist-lock type connection 36a having one or more (shown for example as two) projections extending from the mounting strip and adapted to releasably engage corresponding openings or recesses on a flange portion of the lenses. According to a second embodiment, the lenses 34 are shown to attach to the LED mounting strip 30 using a slide-lock type connection 36b having rails or tabs extending from the mounting strip and adapted to slideably receive the edges of the flange portion of the lenses. According to a third embodiment, the lenses 34 are shown to attach to the LED mounting strip 30 using a snap-fit type connection 36c having one or more (shown for example as two) resilient tabs (e.g. with hooks, etc.) extending from the mounting strip and adapted to releasably engage the flange portion of the lenses.

(16) Referring to FIG. 6, one type of lens is shown for use with a modular LED light fixture for low temperature applications according to an exemplary embodiment. The lens 34a is shown having a flange portion (for engaging the LED mounting strip) and an opening for directing light emitted from the associated LED to a open dish-type (e.g. parabolic, etc.) diffuser. The geometry of the diffuser may be any of a wide variety of geometries intended to provide a specific light dispersion profile.

(17) Referring to FIG. 7, another type of lens is shown for use with a modular LED light fixture for low temperature applications according to an exemplary embodiment. The lens 34b is shown having a flange portion (for engaging the LED mounting strip) and a closed diffuser in the shape on an elongated dome-like structure (shown by way of example with varying degrees of length and curvature) for directing light emitted from an associated LED in a particular light dispersion profile.

(18) Referring to FIG. 8, yet another type of lens is shown for use with a modular LED light fixture for low temperature applications according to an exemplary embodiment. The lens 34c is shown having a flange portion (for engaging the LED mounting strip) and a closed diffuser in the shape on a substantially circular dome-like structure (shown by way of example with varying degrees of curvature) for directing light emitted from an associated LED in a particular light dispersion profile. Although only several examples of lenses have been illustrated in the embodiments of the present application, any of a wide variety of lenses may be used in any particular pattern or combination to support the modularity of the fixture to be adapted or customized to suit a particular low temperature lighting application.

(19) According to any exemplary embodiment, a lighting and energy conservation system for low temperature applications includes a modular LED light fixture having interchangeable lenses for LEDs on mounting strips mounted within elongated reflective channels in the fixture body. According to one embodiment, the low temperature application includes warehouse-type freezers or similar cold storage facilities, having long aisles, tall ceilings and tall stacks or racks of products on each side of the aisles. For example, such an aisle may be approximately 40 feet high and 10 feet wide, or 30 feet high and 10 feet wide, or any other dimension suited to stacking and cold-storing products in a readily retrievable manner. The property of an LED providing a point source of light makes the LED well-suited for providing effective illumination for such a challenging application. By providing a plurality of lenses having different optical characteristics, light output profiles can be individually customized to direct the light to where it is most needed. For example, in such warehouse freezer aisle applications, the light output can be directed primarily toward the aisle floor and the vertical plane of the racks, rather than being wasted on other unnecessary locations.

(20) Further, the modular nature of the fixture permits any number of reflective channels, with LED mounting strips disposed therein (e.g. two, four, six, eight, etc.) as needed to accommodate a particular application. The multi-position power control device may include a four-position switch to fine tune the light output intensity level (e.g. 3.75 percent incrementally until about 30%). According to one embodiment, multi-position power control device uses pulse width modulation, so that the adjustment will not waste energy. The four-position switch is also intended to improve the lifetime of the fixture without wasting energy. It is generally understood that lifetime of an LED is defined as 30% lumen depreciation. Accordingly, through use of the multi-position power control device for each LED mounting strip, the light output intensity may be set at 70 percent initially and as the LEDs in the fixture approach an end of life condition (e.g. 70 percent of initial lumen), the multi-position power control device can be adjusted back to 100 percent light output intensity to maintain the desired light output intensity over a longer lifetime without initially wasting energy. In order to further enhance the lifetime of the other components of the modular fixture (to approach the enhanced life of the LEDs), the fixture includes features that improve and facilitate the ease of serviceability, because the life of the fixture is determined by the life of all of its components. The fixture includes a readily replaceable power supply (e.g. snap-in or attached by threaded connectors). Also, the LED driver is arranged as a plug-in device that is easily and readily replaced. The LED mounting strips are also mounted using snap-in (plug and play) or easily accessed threaded connectors). The modular fixture is also shown to include an open structure for enhanced convention heat transfer and a coated structure for enhanced radiation heat transfer of the heat generated by the LEDs.

(21) The relatively instant-on nature of the modular LED light fixture of the lighting and energy conservation system is intended to allow the light fixtures to be turned-off when access to the freezer is not desired, thus enhancing efficiency by conserving energy that would otherwise be used by the light fixture, and reducing or eliminating the heat contribution to the freezer from the light fixtures, that must otherwise be overcome by the refrigeration system.

(22) It is also important to note that the construction and arrangement of the elements of the modular low temperature LED light fixture as shown (schematically or otherwise) in the embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible without materially departing from the novel teachings and advantages of the subject matter recited.

(23) Accordingly, all such modifications are intended to be included within the scope of the present invention. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the preferred and other exemplary embodiments without departing from the spirit of the present invention.

(24) Unless otherwise indicated, all numbers used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending at least upon the specific analytical technique, the applicable embodiment, or other variation according to the particular configuration of the reflector and coating.

(25) The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes and omissions may be made in the design, operating configuration and arrangement of the preferred and other exemplary embodiments without departing from the spirit of the present invention as expressed in the appended claims.