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`Ex. 1010
`Ex. 1010
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`as) United States
`a2) Patent Application Publication
`(10) Pub. No.: US 2009/0086476 Al
`
`(43) Pub. Date: Apr. 2, 2009
`Tickneret al.
`
`US 20090086476A1
`
`(54)
`
`LIGHT EMITTING DIODE RECESSED
`LIGHT FIXTURE
`
`(75)
`
`Inventors:
`
`Jerold Tickner, Newnan, GA (US);
`Scott David Wegner, Peachtree
`City, GA (US); Evans Edward
`Thompson,II, Fairburn, GA (US)
`
`Correspondence Address:
`KING & SPALDING LLP
`1180 PEACHTREE STREET
`
`ATLANTA, GA 30309-3521 (US)
`
`(73)
`
`Assignee:
`
`Cooper Technologies Company,
`Houston, TX (US)
`
`(21)
`
`Appl. No.:
`
`12/235,116
`
`(22)
`
`Filed:
`
`Sep. 22, 2008
`
`Related U.S. Application Data
`
`(60)
`
`Provisional application No. 60/994,792, filed on Sep.
`21, 2007, provisional application No. 61/010,549,
`filed on Jan. 9, 2008, provisional application No.
`61/065,914,filed on Feb. 15, 2008, provisional appli-
`cation No. 61/090,391, filed on Aug. 20, 2008.
`
`Publication Classification
`
`(51)
`
`Int. Cl.
`(2006.01)
`F21V 21/04
`(2006.01)
`F21V 29/00
`(2006.01)
`F21V 7/00
`(2006.01)
`F21K 7/00
`(52) US. CL .... 362/231; 362/234; 362/364; 362/249.02;
`362/235; 362/230
`
`(57)
`
`ABSTRACT
`
`A recessed light fixture includes an LED module, which
`includes a single LED packagethat is configured to generate
`all light emitted by the recessed light fixture. For example, the
`LED package can include multiple LEDs mounted to a com-
`mon substrate. The LED package can be coupled to a heat
`sink for dissipating heat from the LEDs. The heat sink can
`include a core member from whichfins extend. Each fin can
`include one or morestraight and/or curved portions. A reflec-
`tor housing may be coupledto the heat sink and configured to
`receive a reflector. The reflector can have any geometry, such
`as a bell-shaped geometry including tworadii of curvature
`that join togetherat an inflection point. An optic coupler can
`be coupled to the reflector housing and configured to cover
`electrical connections at the substrate andto guidelight emit-
`ted by the LED package.
`
`
`
`
`
`Patent Application Publication
`
`Apr. 2, 2009 Sheet 1 of 12
`
`US 2009/0086476 Al
`
`
`
`
`FIG. 1
`
`710c
`
`FIG. 2
`
`
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`Patent Application Publication
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`Apr. 2, 2009 Sheet 2 of 12
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`US 2009/0086476 Al
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`
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`Patent Application Publication
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`Apr. 2, 2009 Sheet 3 of 12
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`US 2009/0086476 A1
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`315
`
`300
`
`\
`
`i ___
`
`1 EEE
`
`FIG. 5
`
`
`
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`Patent Application Publication
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`Apr. 2, 2009 Sheet 4 of 12
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`US 2009/0086476 Al
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`300
`
`
`
`Patent Application Publication
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`Apr. 2, 2009 Sheet 5 of 12
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`US 2009/0086476 A1
`
`
`
`
`
`Patent Application Publication
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`Apr. 2, 2009 Sheet 6 of 12
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`US 2009/0086476 Al
`
`
`SS
`
`310
`
`317
`
`otf
`
`
`
`
`
`
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`
`
`FIG. 13
`
`
`
`Patent Application Publication
`
`Apr. 2, 2009 Sheet 9 of 12
`
`US 2009/0086476 Al
`
`1400
`
`METHOD FORINSTALLING
`AN LED MODULEIN AN EXISTING,
`
`NON-LED FIXTURE
`
`1410
`
`TITLE 24
`NO
`
`COMPLAINT
`9
`
`
`
`CUT WIRESIN THE EXISTING FIXTURE,
`REMOVING AN EDISON BASE FROM
`THE FIXTURE
`
`1415
`
`1420
`
`1425
`
`1430
`
`RELEASE THE SOCKET FROM
`THE EXISTING FIXTURE
`
`SCREW AN EDISON BASE
`ADAPTER INTO THE SOCKET
`
`PLUG WIRING FROM THE
`LED MODULE INTO THE
`EDISON BASE ADAPTER
`
`MOUNT THE EDISON BASE ADAPTER
`AND SOCKET TO A BRACKET ON
`THE LED MODULE
`
`1435
`
`SQUEEZE TORSION SPRINGS ON THE
`
`LED MODULE TOGETHER
`
`1440
`
`1445
`
`INSTALL BRACKET ENDS OF THE
`TORSION SPRINGS IN THE
`RECESSED HOUSING
`
`ROUTE WIRES INTO FIXTURE AND
`PUSH LED MODULE FLUSH
`TO CEILING SURFACE
`
`CUT WIRES ON AN EDISON BASE
`ADAPTER TO REMOVEAN EDISON
`SGREW-IN PLUG
`
`CONNECT THE WIRES FROM THE
`EDISON BASE ADAPTER TO THE
`EXISTING FIXTURE, AND PLUG WIRING
`OMSONASEADAPTER. THE
`
`MOUNT THE EDISON BASE
`ADAPTER TO A BRACKET ON
`THE LED MODULE
`
`FIG. 14
`
`
`
`Patent Application Publication
`
`Apr. 2, 2009 Sheet 10 of 12
`
`US 2009/0086476 Al
`
`
`1520a
`
`FIG. 15
`
`
`
`Patent Application Publication
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`Apr. 2, 2009 Sheet 11 of 12
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`US 2009/0086476 Al
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`
`
`FIG. 17
`
`330 3304
`
`330
`
`330bb
`
`——yOS
`
`
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`Patent Application Publication
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`Apr. 2, 2009 Sheet 12 of 12
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`US 2009/0086476 Al
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`
`
`FIG. 19
`
`2005
`
`2005
`
`2015
`
`2010
`
`2015
`
`2010
`
`SL
`
`FIG. 20
`
`
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`US 2009/0086476 Al
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`Apr. 2, 2009
`
`LIGHT EMITTING DIODE RECESSED
`LIGHT FIXTURE
`
`RELATED APPLICATIONS
`
`[0001] This application claimspriority under 35 U.S.C. §
`119 to US. Provisional Patent Application No. 60/994,792,
`titled “Light Emitting Diode Downlight Can Fixture,”filed
`Sep. 21, 2007, U.S. Provisional Patent Application No.
`61/010,549, titled “Diverging Reflector for Light Emitting
`Diode or Small Light Source,”filed Jan. 9, 2008, U.S. Provi-
`sional Patent Application No. 61/065,914, titled “Dimmable
`LED Driver,’filed Feb. 15, 2008, and U.S. Provisional Patent
`Application No. 61/090,391, titled “Light Emitting Diode
`Downlight Can Fixture,”filed Aug. 20, 2008. In addition, this
`application is related to co-pending U.S. patent application
`Ser. No.
`, titled “Diverging Reflector,”filed Sep. 22,
`2008, U.S. patent application Ser. No.
`, titled “Ther-
`mal Management for Light Emitting Diode Fixture,” filed
`Sep. 22, 2008, U.S. patent application Ser. No.
`, titled
`“Optic Coupler for Light Emitting Diode Fixture,”filed Sep.
`22, 2008, and U.S. Design patent application No. 29/305,946,
`titled “LED Light Fixture,”filed Mar. 31, 2008. The complete
`disclosure of each of the foregoing priority and related appli-
`cations is hereby fully incorporated herein by reference.
`
`TECHNICAL FIELD
`
`generally require complex electrical and thermal manage-
`ment systems. Therefore, traditional recessed light fixtures
`have not used LED light sources. Accordingly, a need cur-
`rently exists in the art for a recessed light fixture that uses an
`LED light source.
`
`SUMMARY
`
`[0008] The invention provides a recessed light fixture with
`an LED light source. The light fixture includes a housing or
`“can” within which an LED module is mounted. The LED
`module includes a single LED packagethat generatesall or
`substantially all the light emitted by the recessed light fixture.
`For example, the LED package can include one or more LEDs
`mounted to acommon substrate. Each LED is an LED die or
`LED elementthat is configured to be coupled to the substrate.
`The LEDs can be arranged in any of a numberofdifferent
`configurations. For example, the LEDs can be arranged in a
`round-shaped area having a diameter of less than two inches
`or a rectangular-shaped area having a length of less than two
`inches and a width of less than two inches.
`
`[0009] The LED package can be thermally coupled to a
`heat sink configuredto transfer heat from the LEDs. The heat
`sink can have any of a numberofdifferent configurations. For
`example, the heat sink can include a core member extending
`away from the LED package andfins extending from the core
`member. Each fin can include a curved, radial portion and/or
`a straight portion. For example, each fin can include a radial
`[0002] The invention relates generally to recessed lumi-
`portion that extends from the core member, andastraight
`naires, and moreparticularly, to a light emitting diode down-
`portion that further extends out from theradialportion.In this
`light can fixture for a recessed luminaire.
`configuration, heat from the LEDscan betransferred along a
`path from the LEDsto the core member, from the core mem-
`berto the radial portionsof the fins, from the radial portions
`of the fins to their correspondingstraight portions, and from
`the correspondingstraight portions to a surrounding environ-
`ment. Heat also can be transferred by convection directly
`from the core member and/or the fins to one or more gaps
`betweenthe fins. The LED package can be coupled directly to
`the core memberor to another member disposed between the
`LED package and the core member.
`[0010] A reflector housing can be mounted substantially
`around the LED package. For example, the reflector housing
`can be coupledto the heat sink and/or the can. The reflector
`housing can be configured to receive a reflector and to serve as
`a secondary heat sink for the LED module. For example, the
`reflector housing can be at least partially composed of a
`conductive material for transmitting heat away from the LED
`package. The reflector can be composed of any material for
`reflecting, refracting, transmitting, or diffusing light from the
`LED package. For example, the reflector can comprise a
`specular, semi-specular, semi-diffuse, or diffuse finish, such
`as gloss white paint or diffuse white paint. The reflector can
`have any of a number of different configurations. For
`example, a cross-sectional profile of the reflector can have a
`substantially bell-shaped geometry that includes a smooth
`curve comprising an inflection point. Top and bottom portions
`of the curve are disposed on opposite sides of the inflection
`point. To meet a requirement of a top-down flash while also
`creating a smooth, blendedlight pattern, the bottom portion
`ofthe curve can be more diverging than the top portion of the
`curve.
`
`BACKGROUND
`
`[0003] A luminaire is a system for producing, controlling,
`and/or distributing light for illumination. For example, a
`luminaire can include a system that outputs or distributes light
`into an environment, thereby allowing certain items in that
`environmentto be visible. Luminairesare often referred to as
`
`“light fixtures”’.
`[0004] A recessed light fixture is a light fixture that is
`installed in a hollow opening in a ceiling or other surface. A
`typical recessedlightfixture includes hanger bars fastened to
`spaced-apart ceiling supports or joists. A plaster frame
`extends between the hanger bars and includes an aperture
`configured to receive a lamp housingor “can”fixture.
`[0005] Traditional recessed light fixtures include a lamp
`socket coupled to the plaster frame and/orthe can fixture. The
`lamp socket receives an incandescent lamp or compactfluo-
`rescent lamp (“CFL”) discussed above. As is well known in
`the art, the traditional lamp screws into the lamp socket to
`complete an electrical connection between a power source
`and the lamp.
`lighting manufacturers are being
`[0006]
`Increasingly,
`driven to produce energy efficient alternatives to incandes-
`cent lamps. One such alternative was the CFL discussed
`above. CFLsfit in existing incandescent lamp sockets and
`generally use less power to emit the same amountofvisible
`light as incandescent lamps. However, CFLs include mer-
`cury, which complicates disposal of the CFLs and raises
`environmental concerns.
`
`[0007] Another mercury-free alternative to incandescent
`lamps is the light emitting diode (“LED”). LEDsare solid
`state lighting devices that have higher energy efficiency and
`longevity than both incandescent lamps and CFLs. However,
`LEDs do notfit in existing incandescent lamp sockets and
`
`[0011] An optic coupler can be mounted to the reflector
`housing, for covering electrical connections at the substrate
`of the LED package and/or for guiding or reflecting light
`emitted by the LED package. For example, the optic coupler
`
`
`
`US 2009/0086476 Al
`
`Apr. 2, 2009
`
`can include a member with a central channel that is aligned
`with one or more of the LEDs of the LED package such that
`the channel guides light emitted by the LEDs while portions
`of the member around the channel coverthe electrical con-
`
`FIG. 6isa perspective side view ofthe LED module
`[0020]
`of FIG. 3, in accordance with certain exemplary embodi-
`ments.
`
`FIG. 7 is an elevational bottom view of the LED
`[0021]
`module of FIG. 3, in accordance with certain exemplary
`embodiments.
`
`FIG. 8 is a perspective exploded side view of the
`[0022]
`LED module of FIG.3, in accordance with certain exemplary
`embodiments.
`
`nections at the substrate of the LED package. The optic cou-
`pler can have any of a numberofdifferent geometries that
`may or may not correspond to a configuration of the LED
`package. For example, depending on the sizes and locations
`ofthe electrical connections at the substrate, the portion ofthe
`
`optic coupler around the channel can have a substantially FIG.9is an elevational cross-sectional top view of a[0023]
`
`heat sink of the LED module of FIG.3, in accordance with
`square,
`rectangular,
`rounded, conical, or
`frusto-conical
`shape.
`certain exemplary embodiments.
`[0024]
`FIG. 10 illustrates a thermal scan of the heat sink of
`[0012] The LED module can be used in both new construc-
`the LED module of FIG.3, in accordance with certain exem-
`tion and retrofit applications. The retrofit applications can
`plary embodiments.
`include placing the LED module in an existing LED or non-
`LEDfixture. To accommodateinstallation in a non-LEDfix-
`[0025]
`FIG. 11 is a perspective side view of a reflector
`housing of the LED module of FIG. 3, in accordance with
`certain exemplary embodiments.
`[0026]
`FIG. 12 is a perspective side view of a reflector
`being inserted in the reflector housing of FIG. 11, in accor-
`dance with certain exemplary embodiments.
`[0027]
`FIG. 13 is a perspective side view of a trim ring
`LED module,a person can electrically couple an Edison base
`aligned for installation with the reflector housing of FIG. 11,
`adapter to both the existing, non-LEDfixture and the LED
`in accordance with certain exemplary embodiments.
`module. For example, a person can cut at least one wire to
`
`[0028] FIG. 141saflow chart diagram illustrating a method
`remove an Edison base from the existing fixture, cut at least
`for installing the LED module of FIG.3 in an existing, non-
`one other wire to remove an Edison screw-in plug from the
`LEDfixture, in accordance with certain exemplary embodi-
`Edison base adapter, and connect together the cut wires to
`ments.
`electrically couple the Edison base adapter and the existing
`fixture. Alternatively, a person can release a socket from the
`existing fixture and screw the Edison base adapter into the
`socketto electrically couple the Edison base adapter and the
`existing fixture. The junction box can house the Edison base
`adapter andat least a portion of the wires coupled thereto.
`[0013] These and other aspects, features and embodiments
`of the invention will become apparentto a person of ordinary
`skill in the art upon consideration of the following detailed
`description ofillustrated embodiments exemplifying the best
`modefor carrying out the invention as presently perceived.
`
`ture, the LED module can further include a member compris-
`ing a profile that substantially corresponds to an interior
`profile of a can of the non-LEDfixture such that the member
`creates a junction box between the memberanda top ofthe
`can when the LED module is mountedin the can. Toinstall the
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 15 is a perspective side view of the LED mod-
`[0029]
`ule of FIG. 3 connected to a socket of an existing, non-LED
`fixture via an Edison base adapter, in accordance with certain
`exemplary embodiments.
`[0030]
`FIG. 16 is an elevational side view of the Edison
`base adapter ofFIG.15, in accordance with certain exemplary
`embodiments.
`
`FIG. 17 isa perspective top view of an optic coupler
`[0031]
`of the LED module of FIG. 3, in accordance with certain
`exemplary embodiments.
`[0032]
`FIG. 18 is a perspective bottom view of the optic
`coupler of FIG. 17, in accordance with certain exemplary
`embodiments.
`[0033]
`FIG. 19 isa perspective top view of an optic coupler
`of the LED module of FIG. 3, in accordance with certain
`alternative exemplary embodiments.
`[0034]
`FIG. 20 is an exaggerated depiction ofa profile of
`the reflector, in accordance with certain exemplary embodi-
`ments.
`
`For a more complete understanding of the present
`[0014]
`invention and the advantages thereof, reference is now made
`to the following description, in conjunction with the accom-
`panying figures briefly described as follows. The patent or
`application file contains at least one drawing executed in
`color. Copies of this patent or patent application publication
`with color drawing(s) will be provided by the Office upon
`request and paymentof the necessary fee.
`[0015]
`FIG. 1 is an elevational top view of hangerbars, a
`plaster frame, a can, and a junction box of a recessedlighting
`[0035] The following description of exemplary embodi-
`fixture, in accordance with certain exemplary embodiments.
`ments refers to the attached drawings, in which like numerals
`[0016]
`FIG.2 is an elevational cross-sectional side view of
`indicate like elements throughoutthe severalfigures. FIG. 1is
`the recessed lighting fixture of FIG. 1, in accordance with
`an elevational top view of hanger bars 105, a plaster frame
`certain exemplary embodiments.
`110, a can-shaped receptacle for housing a light source (a
`
`[0017] FIG.3is anelevational side view of an LED module
`“can”) 115, and a junction box 120 of a recessed lighting
`of a recessed lighting fixture, in accordance with certain
`fixture 100, according to certain exemplary embodiments.
`FIG. 2 is an elevational cross-sectional side view of the
`exemplary embodiments.
`[0018]
`FIG. 4is an elevational top view of the LED module
`of FIG. 3, in accordance with certain exemplary embodi-
`ments.
`
`DETAILED DESCRIPTION OF EXEMPLARY
`EMBODIMENTS
`
`hangerbars 105,plaster frame 110, can 115, and junction box
`120 of the recessed lighting fixture 100 of FIG. 1, in accor-
`dance with certain exemplary embodiments. With reference
`[0019] FIG.5is an elevational cross-sectional side view of
`
`to FIGS. 1 and 2, the hanger bars 105 are configured to be
`the LED module of FIG.3, in accordance with certain exem-
`mounted between spaced supports or joists (not shown)
`plary embodiments.
`within a ceiling (not shown). For example, ends of the hanger
`
`
`
`US 2009/0086476 Al
`
`Apr. 2, 2009
`
`bars 105 can be fastened to vertical faces of the supports or
`joists by nailing or other means.
`In certain exemplary
`embodiments, the hanger bars 105 can include integral fas-
`teners for attaching the hanger bars 105 to the supports or
`joists, substantially as described in co-pending U.S. patent
`application Ser. No. 10/090,654,
`titled “Hanger Bar for
`Recessed Luminaires with Integral Nail,” and U.S. patent
`application Ser. No. 12/122,945,
`titled “Hanger Bar for
`Recessed Luminaires with Integral Nail,’ the complete dis-
`closures of which are hereby fully incorporated herein by
`reference.
`
`[0036] The distance between the supports orjoists can vary
`to a considerable degree. Therefore, in certain exemplary
`embodiments,
`the hanger bars 105 can have adjustable
`lengths. Each hanger bar 105 includes twointer-fitting mem-
`bers 105a and 105d that are configured to slide in a telescop-
`ing mannerto provide a desired length of the hanger bar 105.
`A person of ordinary skill in the art having the benefit of the
`present disclosure will recognize that many other suitable
`meansexist for providing adjustable length hanger bars 105.
`For example, in certain alternative exemplary embodiments,
`one or more of the hanger bars described in U.S. Pat. No.
`6,105,918, titled “Single Piece Adjustable Hanger Bar for
`Lighting Fixtures,” the complete disclosure of which is
`hereby fully incorporated herein, may be utilized in the light-
`ing fixture 100 of FIG.1.
`[0037] The plaster frame 110 extends between the hanger
`bars 105 and includes a generally rectangular,flat plate 110¢
`with upturned edges 1105. For example, the flat plate 110a
`can rest on a top surfaceofthe ceiling. The junction box 120
`is mounted to a top surface 110aaoftheflat plate 110a. The
`junction box 120 is a box-shaped metallic container that
`typically includes insulated wiring terminals and knock-outs
`for connecting external wiring (not shown) to an LED driver
`(not shown) disposed within the can 115 of the light fixture
`100 or elsewhere within the light fixture 100.
`the plaster
`[0038]
`In certain exemplary embodiments,
`frame 110 includes a generally circular-shaped aperture 110c
`sized for receiving at least a portion of the can 115 there-
`through. The can 115 typically includes a substantially dome-
`shaped memberconfigured to receive an LED module (not
`shown) that includes at least one LED light source (not
`shown). The aperture 110c providesan illumination pathway
`for the LED light source. A person of ordinary skill in theart
`having the benefit of the present disclosure will recognize
`that, in certain alternative exemplary embodiments, the aper-
`ture 110c¢ can have another, non-circular shape that corre-
`sponds to an outerprofile of the can 115.
`[0039]
`FIGS. 3-8illustrate an exemplary LED module 300
`of the recessed lighting fixture 100 of FIG. 1. The exemplary
`LED module 300 can be configuredfor installation within the
`can 115 ofthe lighting fixture 100 ofFIG. 1. The LED module
`300 includes an LED package 305 mounted to a heat sink 310.
`The LED package 305 may be mounted directly to the heat
`sink 310 or with one or more other components mounted
`in-between the LED package 305 and the heat sink 310.
`[0040] The LED package 305 includes one or more LEDs
`mounted to a common substrate 306. The substrate 306
`includes one or more sheets of ceramic, metal, laminate,
`circuit board, mylar, or another material. Each LED includes
`a chip of semi-conductive material that is treated to create a
`positive-negative (“p-n’’) junction. When the LED package
`305is electrically coupled to a power source, such as a driver
`
`315, current flows from the positive side to the negative side
`of each junction, causing charge carriers to release energy in
`the form of incoherentlight.
`[0041] The wavelength or color of the emitted light
`depends on the materials used to make the LED package 305.
`For example, a blue or ultraviolet LED can include gallium
`nitride (“GaN”) or indium gallium nitride (“InGaN”), a red
`LED can include aluminum gallium arsenide (“AlGaAs”),
`and a green LED can include aluminum gallium phosphide
`(“AlGaP”). Each of the LEDs in the LED package 305 can
`produce the sameor a distinct color of light. For example, the
`LED package 305 can include one or more white LED’s and
`one or more non-white LEDs, such as red, yellow, amber, or
`blue LEDs, for adjusting the color temperature output of the
`light emitted from the fixture 100. A yellow or multi-chro-
`matic phosphor may coat or otherwise be used in a blue or
`ultraviolet LED to create blue and red-shifted light that essen-
`tially matches blackbody radiation. The emitted light
`approximates or emulates “white,” incandescent light to a
`human observer. In certain exemplary embodiments,
`the
`emitted light includes substantially white light that seems
`slightly blue, green, red, yellow, orange, or some other color
`or tint. In certain exemplary embodiments,the light emitted
`from the LEDsin the LED package 305 has a color tempera-
`ture between 2500 and 5000 degrees Kelvin.
`[0042]
`In certain exemplary embodiments, an optically
`transmissive or clear material (not shown) encapsulates at
`least a portion of the LED package 305 and/or each LED
`therein. This encapsulating material provides environmental
`protection while transmitting light from the LEDs. For
`example, the encapsulating material can include a conformal
`coating, a silicone gel, a cured/curable polymer, an adhesive,
`or someother material knownto a person of ordinary skill in
`the art having the benefit of the present disclosure. In certain
`exemplary embodiments, phosphors are coated onto or dis-
`persed in the encapsulating material for creating white light.
`Incertain exemplary embodiments, the white light has a color
`temperature between 2500 and 5000 degrees Kelvin.
`[0043]
`In certain exemplary embodiments, the LED pack-
`age 305 includes one or more arrays of LEDs that are collec-
`tively configured to produce a lumen output from 1 lumen to
`5000 lumensin an area having less than two inches in diam-
`eter or in an area having less than twoinchesin length and less
`than two inchesin width. In certain exemplary embodiments,
`the LED package 305 is a CL-L220 package, CL-L230 pack-
`age, CL-L240 package, CL-L102 package, or CL-L190 pack-
`age manufactured by Citizen Electronics Co., Ltd. By using a
`single, relatively compact LED package 305, the LED mod-
`ule 300 has one light source that produces a lumen output that
`is equivalentto a variety of lamp types, such as incandescent
`lamps, in a source that takes up a smaller volume within the
`fixture. Although illustrated in FIGS. 7 and 8 as including
`LEDsarranged ina substantially square geometry, a person of
`ordinary skill in the art having the benefit of the present
`disclosure will recognize that the LEDs can be arranged in
`any geometry. For example, the LEDs can be arranged in
`circular or rectangular geometriesin certain alternative exem-
`plary embodiments.
`[0044] The LEDsin the LED package 305are attached to
`the substrate 306 by one or moresolderjoints, plugs, epoxy or
`bondinglines, and/or other means for mounting an electrical/
`optical device on a surface. Similarly, the substrate 306 is
`mounted to a bottom surface 310a ofthe heat sink 310 by one
`or moresolder joints, plugs, epoxy or bonding lines, and/or
`
`
`
`US 2009/0086476 Al
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`Apr. 2, 2009
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`other means for mounting an electrical/optical device on a
`surface. For example, the substrate 306 can be mountedto the
`heat sink 310 by a two-part arctic silver epoxy.
`[0045] The substrate 306 is electrically connected to sup-
`port circuitry (not shown) and/orthe driver 315 for supplying
`electrical power and control to the LED package 305. For
`example, one or more wires (not shown) can couple opposite
`ends of the substrate 306 to the driver 315, thereby complet-
`ing a circuit betweenthe driver 315, substrate 306, and LEDs.
`In certain exemplary embodiments,the driver 315 is config-
`ured to separately control one or more portions ofthe LEDs to
`adjust light color or intensity.
`[0046] As a byproduct of converting electricity into light,
`LEDs generate a substantial amount of heat that raises the
`operating temperature of the LEDsif allowed to accumulate.
`This can result in efficiency degradation and premature fail-
`ure of the LEDs. The heat sink 310 is configured to manage
`heat output by the LEDsin the LED package 305. In particu-
`lar, the heat sink 310 is configured to conduct heat away from
`the LEDseven whenthelighting fixture 100 is installed in an
`insulated ceiling environment. The heat sink 310 is composed
`of any material configured to conduct and/or convect heat,
`such as die cast metal.
`
`FIG. 9 is an elevational cross-sectional top view of
`[0047]
`the exemplary heat sink 310. FIG. 10 illustrates a thermal
`scan of the exemplary heat sink 310 in operation. With refer-
`ence to FIGS. 3-10, the bottom surface 310a ofthe heat sink
`310 includes a substantially round member 3104 with a pro-
`truding center member 310c on which the LED package 305
`is mounted. In certain exemplary embodiments, the center
`member310c includes two notches 310d that provide a path-
`way for wires (not shown) that extend between the driver 315
`and the ends of the substrate 306. In certain alternative exem-
`
`plary embodiments, three or more notches 310d may be
`includedto provide pathwaysfor wires. In certain alternative
`exemplary embodiments,
`the bottom surface 310a may
`include only a single, relatively flat member without any
`protruding center member 310c.
`[0048]
`Fins 311 extend substantially perpendicular from
`the bottom surface 310a, towards a top end 310e of the heat
`sink 310. The fins 311 are spaced around a substantially
`central core 905 of the heat sink 310. The core 905 is a
`memberthat is at least partially composed of a conductive
`material. The core 905 can have any of a numberofdifferent
`shapes and configurations. For example, the core 905 can be
`a solid or non-solid memberhaving a substantially cylindrical
`or other shape. Each fin 311 includes a curved,radial portion
`311a and a substantially straight portion 3115. In certain
`exemplary embodiments, the radial portions 311a are sub-
`stantially symmetrical to one another and extend directly
`from the core 905. In certain alternative exemplary embodi-
`ments, the radial portions 311a are not symmetrical to one
`another. Each straight portion 3115 extends from its corre-
`sponding radial portion 311a, towards an outer edge 310/the
`heat sink 310, substantially along a tangent of the radial
`portion 311a.
`[0049]
`Theradius and length of the radial portion 311a@ and
`the length of the straight portion 3116 can vary based on the
`size ofthe heat sink 310, the size ofthe LED module 300, and
`the heat dissipation requirements ofthe LED module 300. By
`way of example only, one exemplary embodimentof the heat
`sink 310 can include fins 311 having a radial portion 311a
`with a radius of 1.25 inches and a length of 2 inches, and a
`straight portion 3116 with a length of 1 inch. In certain alter-
`
`native exemplary embodiments, someorall of the fins 311
`may not include both a radial portion 311a and a straight
`portion 3115. For example, the fins 311 may be entirely
`straight or entirely radial. In certain additional alternative
`exemplary embodiments, the bottom surface 3104 of the heat
`sink 310 may not include the round member 3108. In these
`embodiments, the LED package 305is coupleddirectly to the
`core 905, rather than to the round member 3108.
`[0050]
`Asillustrated in FIG. 10, the heat sink 310 is con-
`figured to dissipate heat from the LED package 305 along a
`heat-transfer path that extends from the LED package 305,
`through the bottom surface 310a of the heat sink, and to the
`fins 311 via the core 905. The fins 311 receive the conducted
`heat andtransfer the conducted heat to the surrounding envi-
`ronment(typically air in the can 115 of the lighting fixture
`100) via convection. For example, heat from the LEDs can be
`transferred along a path from the LED package 305to the core
`905, from the core 905 to the radial portions 311a of the fins
`311, from the radial portions 311a of the fins 311 to their
`corresponding straight portions 3115, and from the corre-
`sponding straight portions 3115 to a surrounding environ-
`ment. Heat also can be transferred by convection directly
`from the core 905 and/or the fins 311 to one or more gaps
`between the fins 311.
`
`Incertain exemplary embodiments, a reflector hous-
`[0051]
`ing 320 is coupled to the bottom surface 310a ofthe heat sink
`310. A person of ordinary skill in the art will recognize that
`the reflector housing 320 can be coupled to anotherportion of
`the LED module 300 or the lighting fixture 100 in certain
`alternative exemplary embodiments. FIG. 11 illustrates the
`exemplary reflector housing 320. With reference to FIGS. 3-8
`and 11, the reflector housing 320 includes a substantially
`round member320a having a top end 3206 and a bottom end
`320c. Each end 3205 and 320c includes an aperture 320ba
`and 320ca, respectively. A channel 320d extends through the
`reflector housing 320 and connects the apertures 320ba and
`320ca.
`
`[0052] The top end 3206 includesa substantially round top
`surface 32066 disposed aroundat least a portion of the chan-
`nel 320d. The top surface 32056 includes one or more holes
`320bc capable of receiving fasteners that secure the reflector
`housing 320 to the heat sink 310. Each fastener includes a
`screw, nail, snap, clip, pin, or other fastening device knownto
`a person of ordinary skill in the art having the benefit of the
`present disclosure. In certain alternative exemplary embodi-
`ments, the reflector housing 320 does not include the holes
`320dc. In those embodiments, the reflector housing 320 is
`formed integrally with the heat sink 310 or is secured to the
`heat sink 310 via means, such as glue or adhesive, that do not
`require holes for fastening. In certain exemplary embodi-
`ments, the reflector housing 320 is configured to act as a
`secondary heat sink for conducting heat away from the LEDs.
`For example, the reflector housing 320 can assist with heat
`dissipation by convecting coolair from the bottom ofthe light
`fixture 100 towards the LED package 305 via one or more
`ridges 321.
`[0053] The reflector housing 320 is configured to receive a
`reflector 1205 (FIG. 12) composed of a material forreflect-
`ing, refracting, transmitting, or diffusing light emitted by the
`LED package 305. The term “reflector” is used hereinto refer
`to any material configured to serve as an optic in a light
`fixture, including any material configured toreflect, refract,
`transmit, or diffuse light. FIG. 12 is a perspective side view of
`the exemplary reflector 1205 being inserted in the channel
`
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`US 2009/0086476 Al
`
`Apr. 2, 2009
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`320d ofthe reflector housing 320, in accordance with certain
`exemplary embodiments. With reference to FIGS. 3-8, 11,
`and 12, when the reflector 1205 is installed in the reflector
`housing 320, outer side surfaces 1205a ofthe reflector 1205
`are disposed along corresponding interior surfaces 320e of
`the reflector housing 320. In certain exemplary embodiments,
`a top end 1205ofthe reflector 1205 abuts an edge surface
`330a of an optic coupler 330, which is mounted to a bottom
`edge 310a of the top surface 320bb. Thereflector 1205 is
`described in more detail below with reference to FIG. 20. The
`optic couple