Lighting device using short thermal path cooling technology and other device cooling by placing selected openings on heat sinks

Abstract

A novel heat sinking technology, uniquely adaptive to LED lighting devices in a generally LED array format containing multiple openings on said heat sink's base portions and optionally fin portions providing “short path cooling” technology. The “short path cooling” technology is thoroughly taught with multiple examples. Also taught, are methods of heat sink area maintenance when said openings are placed on said heat sinks. Indeed, even surface area increases are shown to be possible when multiple openings are placed on said heat sinks. Lastly, other non-LED semiconductor cooling is discussed and illustrated in various figures using said “short path cooling” technology.

Claims

1. A method of efficient cooling of a LED lighting device using a heat sink having a first face and a second face with at least one fin attached to a first side of said face wherein the said at least one fin is exposed to the ambient environment for convective and radiative cooling and wherein the said heat sink has a plurality of openings of a selected shape thru the said at least one fin; and at least one solid state light emitting device thermally and mechanically coupled and electrically isolated to a portion of said heat sink face, generally the second face, but not limited to said second face wherein the cooling environment can be still air and optionally forced air flow.

2. A method of efficient cooling using the heat sink of claim 1 wherein the LED lighting device is replaced with a solid-state semiconductor non-light emitting but power consuming, thus heat generating device.

3. A method of efficient cooling of a LED lighting device of claim 1 wherein at least one of the said heat sink's first face portion can be a base portion upon which the said fin/s is/are attached and said base portion also being allowed to contain a plurality of openings of a selected shape thru the said heat sink second face portion with a depth sufficient to expose the first face portion, exposing a portion of the said heat sink's fin/s base attachment to the said first face area/s allowing air movement in a generally transverse manner, (but not limited to said transverse manner, which said transverse manner may be modified by the orientation of said heat sink) thru the said first and second face portions and into the fin area and out into the environment with a short path air flow and at least one solid state light emitting device thermally and mechanically coupled and electrically isolated, to a selected flat portion preferably, but not limited to, opposite the fin attachment side of said heat sink, wherein the cooling environment can be still air and optionally forced air flow.

4. A method of efficient cooling using the heat sink of claim 3 wherein the LED lighting device is replaced with a solid-state semiconductor non-light emitting but power consuming thus heat generating device.

5. A LED lighting device which said device consists of at least one of a selection of solid state devices as follows: a. A silicon based light emitting device; b. An organic based light emitting device; which said solid state light emitting device/s can emit light of at least one of the following colors: a. A red color as perceived by the human eye, b. A blue color as perceived by the human eye, c. A green color as perceived by the human eye, d. A yellow color as perceived by the human eye, d. An ultra violet color in the invisible range as perceived by the human eye, e. An infra-red color in the invisible range as perceived by the human eye, f. A mixture of red/green/blue (RGB) colors with each color individually controllable using wired or wireless techniques, and an optional base plug of a type selected from the following list: a. Electrical Plug type B22d; b. Electrical Plug type E39; c. Other electrical base plug types both custom designed or commercially available; and an optional direct cable connection from the said LED lighting device to an external power source when not using the said optional base plug; and coupled to a housing, coupled to a heat sink being thermally coupled to a thermally conductive PCB of hybrid composition containing the said plurality of Solid State Light Emitting Devices and wherein the said LED/s device/s are provided with electrical power received from an external power supply thru the said plug/cable and an external socket/cable connection coupled to said external power supply and containing an optional conformal coating on selected areas to protect the said solid state lighting device from moisture, fungus and corrosion and containing an optional transparent/translucent cover with selected openings to allow cooling air to enter in and out of the said solid state lighting device as freely as possible and containing an optional hoop device for support.

6. A LED lighting device of claim 5 wherein the said base plug has been removed and replaced with a direct cable connection from an external power supply to the said at least one LED device/s.

7. A LED lighting device of claim 5 whose said heatsink and said PCB have a plurality of matching openings on selected portion's of said heat sink and correspondingly matching openings on the said PCB mounted mechanically and thermally to said heat sink.

8. A LED lighting device which said device consists of at least one of a selection of solid state devices as follows: a. A silicon based light emitting device; b. An organic based light emitting device; which said solid state light emitting device/s can emit light of at least one of the following colors: a. A red color as perceived by the human eye, b. A blue color as perceived by the human eye, e. A green color as perceived by the human eye, f. A yellow color as perceived by the human eye, d. An ultra violet color in the invisible range as perceived by the human eye, e. An infra-red color in the invisible range as perceived by the human eye, f. A mixture of red/green/blue (RGB) colors with each color individually controllable using wired or wireless techniques, and an optional base plug of a type selected from the following list: a. Electrical Plug type B22d; b. Electrical Plug type E39; c. Other electrical base plug types both custom designed or commercially available; coupled to a housing coupled to a plurality of individual heat sinks; each having a plurality of openings thru selected areas wherein the said openings are selected from the following list: a. a circular shaped opening, b. a square shaped opening, c. a polygon shaped opening, d. an elliptical shaped opening, e. a slot shaped opening, f. an arbitrarily chosen shape of opening; and at least one light emitting device/s which is/are thermally and mechanically mounted and electrically isolated on each of the said individual heat sinks and a housing coupled to a base having a plug for electrical power which housing couples the said individual heat sinks and their corresponding solid state light emitting device/s in a stacked fashion into one unitized lighting device assembly wherein the said LED devices are provided with electrical power received from an external power supply thru the said plug and an external socket coupled to said power supply and containing an optional conformal coating on selected areas to protect the said solid state lighting device from moisture, fungus and corrosion and containing an optional transparent/translucent cover with selected openings to allow cooling air to enter in and out of the said solid state lighting device as freely as possible and containing an optional hoop device for support when not using the said optional transparent/translucent cover.

9. A LED lighting device of claim 8 wherein the said base plug has been removed and replaced with a direct cable connection from an external power supply to the said at least one LED device/s.

10. A LED Lighting Device comprising a plurality of individual heat sink fins each having an L bend portion and a larger area flat portion with a plurality of openings thru selected areas wherein the said openings are selected from the following list: a. a circular shaped opening, b. a square shaped opening, c. a polygon shaped opening, d. an elliptical shaped opening, e. a slot shaped opening, f. an arbitrarily chosen shape of opening; wherein at least one LED lighting device is thermally and mechanically mounted and electrically isolated on each of the said individual L bend portions of said heat sink fins and radially mounted to a central hub wherein the said LEDs face radially outward with respect to the said central hub which is mounted to a center of a roughly cylindrical/conical/half spherical housing comprising a base having a plug for electrical power which said housing couples the said individual heat sinks and their corresponding solid state lighting device/s into one unitized lighting device assembly and also containing a generally circular top portion consisting of a thermally conductive PCB of hybrid composition containing an additional plurality of solid state light emitting devices mounted orthogonal to the central axis of the central hub in a radial fashion which emit light forward axially opposite to the direction of the base portion and having a plurality of openings also in a radial configuration which said openings are aligned with the space portions of the said central hub mounted L bent heat sink fins, and which is mounted mechanically and thermally but electrically insulative, to the most distal portion relative to the plug portion of the solid state lighting device thus forming one unitized lighting device assembly cylindrical in overall shape having said LEDs on both the L bend portions and the said circular top portion electrically connected to receive power and containing an optional conformal coating on selected areas to protect the said solid state lighting device from moisture, fungus and corrosion and containing an optional transparent/translucent cover with selected openings to allow cooling air to enter in and out of the said solid state lighting device as freely as possible.

11. A LED Lighting Device of claim 10 wherein the base portion and housing areas contains a power supply.

12. A high power LED lighting device having a weather and rain water sealed power supply and a plurality of high power LED devices mounted on a high thermally conductive heat sink base portion having a first face and a second face with a dimension greater than 10 inches in diameter if round, and 64 square inches if perimetrical in shape wherein a said first side has a plurality of fins in selected areas while the said second side is a generally flat face but can also have selected portions manifesting fins and wherein the plurality of fins are exposed to the ambient environment wherein the said heat sink base has a plurality of openings of a selected shape thru the said heat sink base portion with the said openings being of sufficient depth and width to expose a portion of the said heat sink's fins attachment base portions wherein the cooling environment can be ambient short path air flow and optionally forced air flow and wherein the heat sink openings are made to maintain a heat sink exposed surface area with a selection of at least one of the following specifications: a. Maintains approximately the same said heat sink fin area but allow short path cooling air movement, b. Increases the said heat sink fin area to allow short path cooling air movement, and wherein the LED mounting PCB is made of copper in optional combination with other materials such as diamond particles, allotropes of carbon etc. and has a high thermal conductivity, possibly exceeding pure copper and having an optional transparent cover and rain water proofing over the LED portion.

13. A high power LED lighting device of claim 12 wherein the heatsink/LED assembly is made of multiple modular units fastened with removable capability into one unit and having optional individual power supplies for each modular unit for purposes of easy field repair and light operational redundancy.

14. A heat sinking apparatus consisting of a base plate portion having a relatively large area top and bottom side and relatively small area edge thickness sections and which said base portion can be made in a shape selected from the following list: a. A square plate, having a first side and a second side, b. A rectangular plate, having a first side and a second side, c. A round plate, having a first side and a second side, d. An arbitrarily chosen shape plate, having a first side and a second side, with a plurality of fins preferably orthogonally oriented, but not limited to said orthogonal orientation, attached to the said top plate section and optionally to the bottom plate section wherein the said base portion contains selected openings with a depth sufficient to expose a portion of the said fins' attachment point to the said base plate to allow the flow of a cooling medium transversely thru the said base portion from a first side of said base portion to a second side of said base portion and thus pass over at least some of the said plurality of said fins in a relatively short thermal path manner.

15. A heat sinking fin which said fin can be made in a shape selected from the following list: a. A square fin, having a first side and a second side, b. A rectangular fin, having a first side and a second side, c. A round fin, having a first side and a second side, d. A “D” shaped fin with an “L” bend portion on the flat side of the “D”, having a first side and a second side, e. An arbitrarily chosen shape fin, having a first side and a second side, f. An arbitrarily chosen shape fin, having a first side and a second side and at least one “L” bend portion on a chosen section of said arbitrarily chosen shape fin having a first side and a second side, with a plurality of openings thru said fins from said first side to said second side to allow the flow of a cooling medium thru the said fins from the said first side to the said second side wherein the said openings are designed to maintain the exposed fins surface area to a cooling medium according one of a selection of the following specifications: a. An increase of the said fin area resulting in a more efficient heat dissipation of said fins, b. An increase of the said fin area resulting in no change of efficiency of heat dissipation of said fin/s but allowing better cooling medium flow for other purposes, c. An increase of the said fin area resulting in worse efficiency of heat dissipation of said fin/s but allowing better cooling medium flow for other purposes, d. A decrease of the said fin area resulting in a more efficient heat dissipation of said fin/s due to better air flow, e. A decrease of the said fin area resulting in no change of efficiency of heat dissipation of said fin/s but allowing better cooling medium flow for other purposes, f. A decrease of the said fin area resulting in worse efficiency of heat dissipation of said fin/s but allowing better cooling medium flow for other purposes,

16. A Heat Sinking Apparatus for solid state semiconductor/s cooling having a base portion wherein one side has a plurality of fins while the other side is a generally flat face and wherein the plurality of fins are exposed to the ambient environment wherein the said heat sink base has a plurality of openings of a selected shape thru the said heat sink base portion with the said opening being of sufficient depth and width to expose a portion of the said heat sink's fins attachment base portion and at least one heat generating device thermally coupled to a selected flat portion and optionally other portion/s of said heat sink, wherein the cooling environment can be ambient air flow and optionally forced air flow and wherein the heat sink and PCB (when used in conjunction with the said heat sink) openings are made to maintain a heat sink exposed surface area with a selection of at least one of the following specifications: a. Maintains approximately the same said heat sink fin area to allow short path cooling air movement, b. Increases the said heat sink fin area to allow better short path cooling air movement, c. Reduces the said heat sink fin area to allow better short path cooling air movement, d. Maintains the same said heat sink base area to allow short path cooling air movement, e. Reduces the said heat sink base area to allow better short path cooling air movement,

17. A Heat Sinking Apparatus for solid state semiconductor/s cooling having a base portion and at least one flat face and a plurality of fins on each side of the said heat sink's base portion exposed to the ambient environment wherein the said heat sink has a plurality of openings of a selected shape thru the said heat sink base portion with the said opening being thru the base portion exposing the interstitial areas of the fins attachment point to base portions both on the top fins and optionally bottom fins and at least one heat generating device thermally coupled to a selected flat portion and optionally other portion/s of said heat sink, wherein the cooling environment can be ambient air flow and optionally forced air flow and wherein the heat sink and PCB (when used in conjunction with the said heat sink) openings are made to maintain a heat sink exposed surface area with a selection of at least one of the following specifications: a. Maintains approximately the same said heat sink fin area to allow short path cooling air movement, b. Increases the said heat sink fin area to allow better short path cooling air movement, c. Reduces the said heat sink fin area to allow better short path cooling air movement, d. Maintains the same said heat sink base area to allow short path cooling air movement, e. Reduces the said heat sink base area to allow better short path cooling air movement,

18. A Heat Sinking Apparatus for efficient convective cooling having a base portion and at least one flat face and a plurality of fins on each side of the said heat sink's base portion exposed to a gas/liquid wherein the said heat sink has a plurality of openings of a selected shape thru the said heal sink base portion edge/s with the said opening being thru the base portion edges producing a cavitation of the said fins attachment point to base portions both on the top fins and optionally bottom fins; allowing transverse short path cooling medium flow to occur and at least one heat generating device thermally coupled to a selected flat portion and optionally other portion/s of said heat sink, wherein the cooling environment can be ambient air flow and optionally forced air flow and optionally liquid flow wherein the heat sink and PCB (when used in conjunction with the said heat sink) openings are made to maintain a heat sink exposed surface area with a selection of at least one of the following specifications: a. Maintains approximately the same said heat sink fin area to allow short path cooling medium movement, b. Increases the said heat sink fin area to allow better short path cooling medium movement, c. Reduces the said heat sink fin area to allow better short path cooling medium movement, d. Maintains the same said heat sink base area to allow short path cooling medium movement, e. Reduces the said heat sink base area to allow better short path cooling medium movement,

19. A PCB of hybrid composition containing a plurality of openings thru selected areas wherein the said openings are selected from the following list: a. a circular shaped opening, b. a square shaped opening, c. a polygon shaped opening, d. an elliptical shaped opening, e. a slot shaped opening, f. an arbitrarily chosen shape of opening; and containing an array of LEDs which said array is placed on said PCB on selected areas between the said openings allowing efficient LED cooling due to multiple short path cooling medium flow thru the said PCB in a generally transverse manner, but not limited to said transverse manner, which said transverse manner may be modified by the orientation of said PCB relative to cooling medium flow.

20. A PCB of hybrid composition of claim 19 wherein a first side of said PCB is thermally and mechanically bonded to a heat sink having a base portion and fin/s and at least one opening thru base portion approximately matching at least one PCB opening, while the second side contains the said LED array/s.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In a class of embodiments, the present invention consists of a Base Plugged Light Emitting Diode lighting device (one class of embodiments) coupled to an efficient heat sink (another class of embodiments). Also the same efficient heat sink technology is disclosed for other cooling functions. (yet another class of embodiments). The inventor understands that this disclosure could be a teaching solely for a more efficient heat sink, However it will become obvious that this new heat sink technology is uniquely applicable to the cooling of LED devices due to the heat sink using carefully designed openings for efficient cooling and in selected embodiments using transverse slot openings on extruded heat sinks or holes or other shaped openings etc. for non-extruded heat sinks for efficient air flow. The inventor claims by reference other heat sink applications such as, for example efficient cooling of non LED semiconductor devices or liquid pipe cooling in high power electronic devices etc. The inventor further understands that most configurations of heat sinks do function if huge quantities of forced air flow are impinged upon the said heat sinks. However, in the practical world of domestic, office, laboratory, studio, etc. lighting, forced air cooling is seldom used. This invention is ideal for generally ambient still air cooling.

[0052] The object and features of the present invention, as well as various other features and advantages of the present invention will become apparent when examining the descriptions of various selected embodiments taken in conjunction with the accompanying drawings and term definitions in this document in which:

[0053] FIG. 1 shows a partially exploded perspective view of a First Embodiment LED lighting device.

[0054] FIG. 2 shows an assembled perspective view of a LED lighting device in a vertical position.

[0055] FIG. 3 shows an assembled perspective view of a LED lighting device in a horizontal position.

[0056] FIG. 3A shows an assembled perspective view of a LED lighting device in a vertical position.

[0057] FIG. 3B shows a magnified view of a portion of FIG. 3A

[0058] FIG. 3C shows an assembled perspective view of a LED lighting device in a horizontal position.

[0059] FIG. 4 shows a partially exploded perspective view of a Second Embodiment LED lighting device.

[0060] FIG. 4A shows an example PCB layout of a Second Embodiment LED lighting device.

[0061] FIG. 5 shows an assembled perspective view of a Second Embodiment LED lighting device.

[0062] FIG. 6 shows a perspective sectional view of a Second Embodiment LED lighting device heat sink,

[0063] FIG. 7 shows a second perspective sectional view of a Second Embodiment LED lighting device heat sink.

[0064] FIG. 8 shows an end view of a First Embodiment LED lighting device heat sink.

[0065] FIG. 9 shows an end view of a Second Embodiment LED lighting device heat sink.

[0066] FIG. 10 shows an assembled perspective view of a Third Embodiment LED lighting device.

[0067] FIG. 11 shows a partial assembled perspective view of a Third Embodiment LED lighting device.

[0068] FIG. 12 shows an assembled perspective view of a Fourth Embodiment LED lighting device.

[0069] FIG. 13 shows a partial assembled perspective view of a Fourth Embodiment LED lighting device.

[0070] FIG. 14 shows a one-section perspective view of a Fifth Embodiment LED lighting device.

[0071] FIG. 15 shows a one-section perspective view of a Sixth Embodiment LED lighting device.

[0072] FIG. 15A shows a one-section perspective view of a Seventh Embodiment LED lighting device.

[0073] FIG. 15B shows a one-section perspective view of a Eighth Embodiment LED lighting device.

[0074] FIG. 16 shows a partially exploded perspective view of a Ninth Embodiment LED lighting device.

[0075] FIG. 17 shows an assembled perspective view of a Ninth Embodiment LED lighting device.

[0076] FIG. 18 shows an assembled perspective view of a Tenth Embodiment LED lighting device.

[0077] FIG. 18A shows a transparent or translucent protective plastic cover and base as can be optionally used in said Tenth Embodiment LED lighting device.

[0078] FIG. 19 illustrates a perspective view of a first horizontally positioned very common heat sink.

[0079] FIG. 20 illustrates a perspective view of a Eleventh Embodiment second horizontally positioned heat sink of the present invention.

[0080] FIG. 21 illustrates a sectional perspective view of a second horizontally positioned heat sink of the present invention.

[0081] FIG. 22 illustrates a perspective view of a Twelfth Embodiment third horizontally positioned heat sink of the present invention.

[0082] FIG. 23 illustrates a perspective view of a Thirteenth Embodiment horizontally positioned heat sink with power LEDs of the present invention.

[0083] FIG. 24 illustrates a perspective view of a Fourteenth Embodiment fourth horizontally positioned heat sink of the present invention with section E-E indicated.

[0084] FIG. 25 illustrates a perspective view of a Fourteenth Embodiment horizontally positioned heat sink of the present invention with section E-E shown in FIG. 24 removed and arrows F-F indicating further view magnification in FIG. 25A.

[0085] FIG. 25A illustrates a magnified sectional view F-F of FIG. 25.

[0086] FIG. 26 illustrates a perspective view of a Fifteenth Embodiment horizontally positioned heat sink of the present invention showing arrows G-G.

[0087] FIG. 27 illustrates a perspective view of a Fifteenth Embodiment horizontally positioned heat sink of the present invention with section G-G removed.

[0088] FIG. 28 shows an assembled perspective view of an Sixteenth Embodiment LED lighting device.

[0089] FIG. 29 shows a partial view of an Seventeenth Embodiment LED lighting device.

[0090] FIG. 30 shows a partial magnified view of an Seventeenth Embodiment LED lighting device.

[0091] FIG. 31 shows a partially exploded view of the LED assembly of a Seventeenth Embodiment LED lighting device.

[0092] FIG. 32 shows a LED surface mount chip with wide angle light emission.

[0093] FIG. 33 shows a LED surface mount chip with narrow angle light emission.

[0094] FIG. 34 shows a power LED surface mount chip with narrow angle light emission.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0095] The following embodiments are presented for a thorough teaching of the present invention. To aid the reader of this teaching, the various embodiments with their accompanying figures will be explored seriatim in a stand-alone manner whenever possible.

First Embodiment of the Present Invention

[0096] FIG. 1 shows a partially exploded perspective view of a LED lighting device 1 consisting of a metal clad printed circuit board 3 with an array of LEDs 2 mounted thereon. Shown below the said items is an extruded aluminum heat sink 9 with a generally flat surface 4 which is mechanically attached to a housing 6 which is attached to a bayonet base 8 containing two locating lugs 7. The bayonet base illustrated is a type B22d. However, this teaching is not limited to the said bayonet base. A transparent cover 3a is also provided which can come as a transparent/translucent plastic cover or it can have multiple perforations if air flow is needed as will be described in subsequent descriptions of various embodiments of the present invention. The housing 6 contains no built in ballast. Note section A-A in said FIG. 1 for FIG. 2 description.

[0097] FIG. 2 shows an assembled perspective view of a LED lighting device in a vertical position. We will now discuss the thermal aspects of the heat sink 9. When the heat sink 9 begins to absorb heat by conduction from the LEDs 2 via thermally conductive PCB 3, thermally mounted to heat sink 9, air currents will begin to flow. The hottest parts of the heat sink will be the internal spaces of fins 9b, 9c, 9d and 9e located in the crowded areas of the heat sink 9 fins. For clarity heat sink 9 fins 9b, 9c, 9d and 9e have been cut away at section A-A in FIG. 1 to show internal air currents 7a thru 7d. Now therefore, air currents will begin to form, illustrated by arrows 7a, thru 7d. The reader is encouraged to imagine these air currents as occurring not just partially distal to the heat sink 9 fin bottoms as shown by arrows 7a thru 7d, but also very much proximal to the deep inner fin parts of the heat sink 9 where little air current motion is going on partly due to a crowding effect by the closely spaced heat sink 9 fins. The reason for this is that there is no high velocity artificially forced air movement such as provided by a fan, for example. This is a fundamentally inefficient heat sink. Why?

[0098] High school physics teaches us that hot air rises up in still air. So now let us imagine that air depicted by arrow 7a is moving up between the heat sink 9 fins. It will absorb heat from said fins. By the time it has reached the vertical level of arrow 7b, it will have heated somewhat so that that the ΔT between the heat sink 9 fins is significantly reduced.

[0099] Recollect that heat transfer is a function of temperature difference, ΔT between the heat sink 9 and the gently rising air current 7a thru 7b. Now therefore we have a conundrum; by the time we have the same said air current reaching arrow 7c, the said air current is even hotter, reducing the ΔT to almost zero.

[0100] Therefore the said air current goes for a tree ride to a level depicted by arrow 7d, doing no heat absorbing work and out into the environment. Additionally, housing 6 hinders the entrance of air currents at the lowest level of the heat sink 9 since it is butted hard up against the heat sink 9, further decreasing heat sink 9 efficiency. This has been a simplistic explanation since there are complex air currents involved in most heat sink operations, too complex to write here. Suffice to say, the above teaching covers the major effects.

[0101] FIG. 3 shows an assembled perspective view of a LED lighting device in a horizontal position. Here we have a situation much more complex to analyze. Once again, during operation of LED lighting device 1, heating will occur. Air proximal to the LEDs 2 and PCB 3 will absorb heat and will begin to rise, hitting a brick wall so to speak. Said air currents 7 will be forced to bend around the lighting device 1 as depicted by arrow 7e and up into the environment.

[0102] Air currents in and around the heat sink 9 fins are very complex to analyze. Air currents at 7f and 7g depict crudely these air currents rising out of the interstitial spaces of the heat sink 9 fins. Laboratory data has shown that the heat sink 9 does indeed do a reasonable job of heat dissipation, almost as good as in the vertical position. One can speculate that various turbulent short path micro-currents are here occurring in and out of the horizontally placed heat sink 9 fins. Also air currents do not travel along the longitudinal path depicted in FIG. 2, but rise up perpendicularly from the heat sink fins.

[0103] Nevertheless, the present invention is a useful device because it is inexpensive to manufacture and there is minimal pre or post machining necessary on extruded aluminum heat sink 9. A half hoop device with two end clip hooks made of metal or plastic is also shown fitted to grooves 11a to act as a support when placed in a fixture without a plastic cover as shown in FIG. 1. The said half hoop device with two end-clip hooks can also be a full hoop with the clip hooks placed internally at 180° apart. These half hoop or full hoop devices become very necessary when this first embodiment light fixture is long; for example they are presently made in 42 inch (1.07 meters) lengths. Furthermore, these said hoop devices could be used in other similar embodiments. For clarity of other descriptions, they will not be illustrated in following embodiments, but are incorporated herein by reference.

[0104] FIG. 3A shows an assembled perspective view of a First Embodiment LED lighting device in a vertical position similar to device illustrated in FIGS. 1 thru 3. Note that a slot 9b has been added in the area labeled M1.

[0105] FIG. 3B shows a magnified view of area M1 of FIG. 3A. An exemplary slot 9b has been added which cuts thru the PCB 3a and heat sink base 4a (shown in FIG. 3a), exposing the attachment bases of heat sink fins 9a. Air can now enter thru the slot 9b and move over the heat sink bases 9a and on out, cooling the said heat sink fins 9, (shown in FIG. 3a) beginning at the hottest part of the said heat sink which is at the junction of the heat sink fin 9a and the base 4a (shown in FIG. 3a). This is illustrated clearly in FIG. 3C.

[0106] FIG. 3C shows an assembled perspective view of a First Embodiment LED lighting device in a vertical position similar to device illustrated in FIGS. 1 thru 3. Note that a slot 9a has been added, as shown in FIG. 3B. Air currents 7 can now pass right thru the heatsink assembly at the mid-point and bring in fresh cooling air, thus increasing the overall efficiency of the said heatsink assembly. Laboratory experiments have proven this invention to work. For example, adding only two of such slots as illustrated in the previous few paragraphs resulted in an overall reduction of heat sink temperature of approximately 10-15° C. This may seem a little, but it is not; lowering a temperature even slightly can increase LED life substantially.

Second Embodiment of the Present Invention

[0107] FIG. 4 shows a partially exploded perspective view of a Second Embodiment LED lighting device 10 consisting of a metal clad printed circuit board 13 with an array of LEDs 12 mounted transversely thereon as compared to the First Embodiment. Shown below the said items is an extruded aluminum heat sink 19 with a generally flat surface 14 which is mechanically attached to a housing 16 which is attached to a bayonet base 18 containing two locating lugs 17. The bayonet base illustrated is a type B22d. However, this teaching is not limited to the said bayonet base. As can be seen in FIG. 4 and subsequent figures, the LEDs 12 are now situated transversely as compared to the First Embodiment. This is to allow slots 24 to be cut thru printed circuit board 13 for reasons explained hereafter. Extruded aluminum heat sink 19 with a generally flat surface 14 now has been post machined with transverse slots 23 in the said PCB deep enough to expose the bottoms of the heat sink 19 fins. This embodiment illustrates an extreme example of multiple slots for a large heat dissipating capability.

[0108] FIG. 4A shows a view of a Second Embodiment LED lighting device PCB layout in a partial sectional format to show traces connecting the various LEDs. PCB 13 is shown with slots 24, mounting holes 13b, and electrical traces 13c. PCB dimensions are shown as an example, being 57 mm width and 407 mm length. LEDs 12 are shown with their diode symbols to the immediate right of each LED. To the untrained eye, traces 13c are a little difficult to see, but a PCB designer would immediately recognize them. On the top section are pads labeled IN1 and IN2. Also D1, D2, D3, D4 are steering diodes ensuring that the LED array always receives the correct voltage polarity regardless of the IN1 and 1N2 power connection polarity. This example is illustrates clearly that a multiply slotted PCB is indeed possible and practical. The 407 mm length PCB is only one example shown. LED array panels of this general type have been made with lengths of up to two or three meters.

[0109] FIG. 5 shows an assembled perspective view of a Second Embodiment LED lighting device 10 consisting of a metal clad printed circuit board 13 with an array of LEDs 12 mounted transversely thereon as compared to the First Embodiment. Shown below the said items is an extruded aluminum heat sink 19 with a generally flat surface 14 which is mechanically attached to a housing 16 which is attached to a bayonet base 18 containing two locating lugs 17. The bayonet base illustrated is a type B22d. However, this teaching is not limited to the said bayonet base.

[0110] As can be seen in FIG. 5 and subsequent figures, the LEDs 12 are now situated transversely as compared to the First Embodiment. This is to allow slots 24 to be cut thru printed circuit board 13 for reasons explained hereafter. Extruded aluminum heat sink 19 with a generally flat surface 14 which has been post machined with said transverse slots matching the said slots 24 in the said PCB deep enough to expose the bottoms of the heat sink 19 fins. Slots 23 from FIG. 4 are now directly below the matching slots 24 on the PCB. Notice that the heat dissipating area of heat sink 19 has not been disturbed too much and there is still ample flat surface 14 left for conductive heat bonding to the PCB.

[0111] FIG. 6 shows a perspective sectional view of a Second Embodiment LED lighting device heat sink. Sectional views B-B and C-C will now be discussed.

[0112] FIG. 7 shows a second perspective sectional view of a Second Embodiment LED lighting device heat sink with section B-B details. When in an operational heated condition, the heat sink 19 will cause air currents to flow upwards. Unlike the conditions described in the first embodiment we now have a far more efficient air current flow. One of the basic tenets of convective heat transfer is short thermal paths and air velocity and turbulence. Here we have achieved these to a reasonable degree. The air current depicted by arrow 27 traverses right thru the slot in the PCB (24 in FIG. 5) and the slot 23 on said heat sink 19 and then passes past the exposed fins 22 and on out. Additionally, the sharp edges of the slots produce a variety of micro turbulent effects, aiding in heat transfer between the air and the metal heat sink. In the American vernacular, get the air in, grab some heat from the heat sink and “get out of Dodge” and allow a fresh current of air to come in and repeat the process. The inventor has dubbed this process “Short Path Heat Transfer”

[0113] FIG. 8 shows an end view of a First Embodiment LED lighting device heat sink.

[0114] FIG. 9 shows a sectional end view C-C of a Second Embodiment LED lighting device heat sink. The arrows 7 and 27 speak for themselves. In the former case as shown in FIG. 8, no air currents 7 can flow thru heat sink 9. In the latter case shown in FIG. 9, however, air currents 27 do flow fast and free thru heat sink 19 via the slot 23 (shown with a cross hatch for easy identification), cut into the surface 14 of heat sink 19.

Third Embodiment of the Present Invention

[0115] FIG. 10 shows an assembled perspective view of a Third Embodiment LED lighting device 39. It consists of a plurality of individual heat sink fins 30 with LEDs 34 mounted on the bent portions of heat sink fins 30. The entire assembly is fastened to housing 36, bayonet base 32 containing two locating lugs 33. The entire heatsink and LED assemblies are fastened to the housing using appropriate fasteners 37 and spacers 38 as shown in FIG. 10.

[0116] PCBs, will no longer be shown in further descriptions to not overcrowd the illustrations and the cost effective manufacturing and wiring technique will not be discussed since it is well known in the art.

[0117] The heat sink fins 30 with their bent portion are now not extrusions but stamped metal devices. The said stamped metal can be the metal clad PCB material used in previous embodiments or conventional thin sheet metal with the LEDs 34 mounted electrically insulated from the heat sink fins 30, but thermally conductive. A variety of techniques are known in the art. Serial/parallel electrical connections to the LED arrays are also well known in the art and need not be discussed herein. For example all the LEDs 34 could be solder flowed on one appropriately slotted PCB and then the said PCB LED assembly is solder flowed to all the said heatsinks fins 30 in one manufacturing operation using various assembly jigs etc.

[0118] FIG. 11 shows a partial assembled perspective view of the said Third Embodiment LED lighting device 39 of FIG. 10. Air currents depicted by arrows 27 can be seen to flow freely cooling each LED 34 heat sink 30 segment. This short path fast air flow device has proven to be very efficient.

[0119] Generally each heat sink 30 segment is should be sized to have an area of 30 to 45 square centimeters per Watt of total led power dissipation on each heatsink fin 30 segment. This is a tall order in many respects for a single fin. The next Fourth Embodiment helps us out here by doubling the fin area. It is important to note that the LEDs must be at a fairly higher temperature than the environment for heat transfer to occur. So it is a cool-me-if-you-can game between the LED and the thermal engineer. Enough said; it is all in the skill of the art.

Fourth Embodiment of the Present Invention

[0120] FIG. 12 shows an assembled perspective view of a Fourth Embodiment LED lighting device 49. It consists of a plurality of individual heat sink fins 40 with LEDs 44 mounted on the double bent portions of heat sink fins 40. The entire assembly is fastened to housing 36, bayonet base 33 containing two locating lugs 33, using appropriate fasteners and spacers (not shown). The cost effective manufacturing and wiring technique will not be discussed since it is well known in the art. The heat sink fins 30 with their double bent portion are now not extrusions but stamped metal devices. The said stamped metal can be the metal clad PCB material used in previous embodiments or thin sheet metal with the LEDs 44 mounted electrically insulated from the double heat sink fins 30, but thermally conductive. A number of techniques are known in the art.

[0121] FIG. 13 shows a partial assembled perspective view of the said Fourth Embodiment LED lighting device 41. Air currents depicted by arrows 27 can be seen to flow freely cooling each LED 44 heat sink 40 segments. This short path fast air flow device has proven to be very efficient. This fourth embodiment has a higher power dissipation capability than the third embodiment due to the double surface area of the heat sink 40.

Fifth Embodiment of the Present Invention

[0122] FIG. 14 shows a one section perspective view of a Fifth Embodiment LED lighting device 61. It is identical to the sections in FIG. 12 with the exception that slots 62 have been added. Now then the neophyte will say “adding slots reduces the heat sink area”. Not so; if the slot width is the same as the heat sink fin thickness, the area is increased by the added annular area of the heat sink fin thickness . . . . Herein we set forth the explanation. Let us imagine a heat sink fin that is one tenth of an inch thick. For easy mental calculation, let's cut a rectangular slot one tenth of an inch wide and one inch long. Now from each side of the said fin we have removed:

(0.10×1.0)inches+(First side of rectangular surface)

(0.10×1.0)inches+(Second side of rectangular surface)=0.02 square inches

However we have exposed the inner thickness of the said fin thus:

(0.10×1.0)inches+(First long thickness side of rectangular opening)

(0.10×1.0)inches+(Second long thickness side of rectangular opening)

(0.10×0.10)inches+(First short thickness side of rectangular opening)

(0.10×0.10)inches+(Second short thickness side of rectangular opening)=0.022 square inches

[0123] Now therefore, we have created a heat sink fin 60 which is slightly better in area and allows more free airflow as depicted by arrow 27. Additionally, the sharp edges of the slots produce a variety of micro turbulent effects increasing convective heat transfer. Moving air turbulence disrupts laminar air flow which in turn achieves better convective heat transfer. The slot population density is limited by the heat sink fin 60's thermal conductivity since slotting interferes with the said fin's conductive heat transfer. So for example, if the fin was copper, it could have twice the number of slots as aluminum since copper has roughly two times better heat conduction. Also slot orientation is important. Notice that FIG. 14 shows the slots in a radial pattern. This not an accident; this configuration allows fin 60 heat conduction to radiate out radially and thus the slots 62 will be supplied with ample heat from its source which is the top portion where the LEDs 44 are located.

[0124] Although the inventor demonstrates that heat sink area can be maintained when slots, holes or other shape of openings are properly applied, there may be other cases where a relatively small reduction of heat sink area may be allowed if the cooling advantages outweigh the loss of said heat sink area and are hereby incorporated by reference. As a general note, when dealing with a heatsink base that has fins attached to the said base, it is not necessary to maintain the same exposed surface area of the said base because the primary function of the base is to conduct heat to the fins, not to dissipate the majority of the heat. This is why the said base is usually much thicker than the fins. However when slots, holes or other shape of openings are placed on the fins, maintaining the surface area is important. Even so, the said slots, holes or other shape of openings can be larger if experiment shows that air flow is improved and heat dissipation is increased. It's all in the art of the thermal science involved and laboratory experimentation, and therefore these described techniques are incorporated by reference.

Sixth Embodiment of the Present Invention

[0125] FIG. 15 shows a one section perspective view of a Sixth Embodiment LED lighting device 71 wherein a plurality of holes have been added instead of slots. With judicious hole 72 sizing and number and placement of said holes, this heat sink 70 has the greatest potential for efficient short path air circulation. Once again arrow 27 illustrates the short path air flow.

Seventh Embodiment of the Present Invention

[0126] FIG. 15A shows a one section perspective view of a Seventh Embodiment LED lighting device 61a wherein a plurality of openings have been made using a metal piercing technique which does not remove any metal such as in drilling or punching holes. Once again, heatsink area is increased and air flow is improved. The view in FIG. 15A is reversed for clarity. The LEDs 44 are distal, mounted on L bend 61b, hence the dashed lines indicating their presence. The heatsink fin 60a is pierced with a plurality of openings 62a thru which air can circulate. When the heat sink fin 60a is pierced by a hardened tool spike that generally is shaped like a sharp nail point, an opening 62a is forced into the metal fin 60a. Additionally, triangular segments 63 are also produced which once again give rise to increased exposed surface area due to the triangular segments 63 thickness sections. Arrow 27 illustrates air flow thru opening 62a.

Eighth Embodiment of the Present Invention

[0127] FIG. 15B shows a one section perspective view of a Eighth Embodiment LED lighting device 71a wherein a plurality of openings have been made using a metal stamping technique which does not remove any metal such as in drilling or punching holes. Once again, heatsink area is increased and air flow is improved. The view in FIG. 15B is reversed for clarity. The LEDs 44 are distal, mounted on L bend 71b, hence the dashed lines indicating their presence. The heatsink fin 70a is pierced with a plurality of openings 72a thru which air can circulate. When the heat sink fin 70a is stamped with a hardened stamping and partial punching tool, an opening 72a is forced into the metal fin 70a. Additionally, bridge-like segments 73 are also produced which once again give rise to increased exposed surface area due to the bridge-like segments 73 thickness sections. Arrow 27 illustrates air flow thru opening 72a.

Ninth Embodiment of the Present Invention

[0128] FIG. 16 shows a partially exploded perspective view of a Ninth Embodiment LED lighting device 59. Its purpose is to produce a lighting device as the previous embodiments, but having an omnidirectional light emission capability. It consists of heat sink sections 50 with slots 51, and LEDs 56 mounted on bent portions of said heat sinks 50 which are fastened to a central hub 55. The said assembly is attached to a housing rim 57 which is an integral part of housing 58 with a base bayonet 57 with two prongs 53. As in previous illustrations, the bayonet base illustrated is a type B22d. However, this teaching is not limited to the said bayonet base. An LED 56 embellished end cap 68 is also shown exploded from the fixture 59 for clarity. When assembled, the top cap 68 is edge bonded to the plurality of heat sinks 50 using thermally conductive epoxy or the like to thermally couple the LEDs 56 on said top cap to the plurality of heat sinks 50. To not impede airflow, a plurality of openings 60 is also shown. Once again, electrical connections are not shown; they are well known in the art. The base portion 58, 57 can contain ballast electronics which are also well known in the art and are not illustrated.

[0129] FIG. 17 shows an assembled view of the Ninth Embodiment LED lighting device 59. The slots 51 are carefully designed so as to keep the heat sink area the same as discussed previously. This Ninth Embodiment LED lighting device 59 is capable of very efficient heat dissipation. As mentioned previously, when assembled, the top cap 68 is edge bonded to the plurality of heat sinks 50 using thermally conductive epoxy or the like to thermally couple the LEDs 56 on said top cap 68 to the plurality of heat sinks 50. A transparent perforated plastic cover is generally used with this lighting device 69. (Not shown here, but is illustrated in FIG. 18A).

Tenth Embodiment of the Present Invention

[0130] FIG. 18 shows an assembled view of the Tenth Embodiment LED lighting device 69, wherein the plurality of heat sinks 70 are made from preferably, but not limited to, perforated aluminum. The holes 61 are carefully designed so as to keep the heat sink area substantially the same surface area as discussed previously. This Tenth Embodiment LED lighting device 69 is capable of very efficient heat dissipation, even better than Embodiment Nine. The top cap 68 is edge bonded to the plurality of heat sinks 70 using thermally conductive epoxy or the like to thermally couple the LEDs 56 on said top cap to the plurality of heat sinks 70. A transparent perforated plastic cover is generally used with this lighting device 69. (Shown in FIG. 18A). The said plastic cover is also carefully designed, with little or no perforations in front of the LEDs, and large perforations between the heat sink 70 “wings”. The top portion of the lighting device 68 is also covered by the same said cover and slotted in the triangular region 71 between the “star” patterned LEDs 56. The better this said lighting device can “breathe”, the cooler it will run.

[0131] FIG. 18A shows an assembled view of the Eighth Embodiment LED lighting device 69, wherein none of the interior is shown. Only the transparent or translucent protective plastic cover 71 and base portion is illustrated. The said assembly is attached to a housing rim 57 which is an integral part of housing 58 with a base bayonet 57 with two prongs 53. The cover portion 71 contains a plurality of slots 72 designed to allow air to pass into and out of the LED light fixture. On the top portion are shown triangular openings 73 to allow air in or out as described for the said slots. Although slots and triangular openings are shown, this invention is not limited to this said configuration. During manufacturing, other constraints may apply, necessitating other types of openings and are hereby incorporated by reference. Additionally, the portions of the said plastic cover 71 can also have lenses molded in the areas directly in front of each LED for further light dispersion and is hereby incorporated by reference

Other Applications of the Present Invention

[0132] Heretofore the novel heat sink structure has been taught as applied to LED lighting devices. Nevertheless, in order to comply with the requirement to offer a full disclosure of the present invention, the inventor will now illustrate an alternate semiconductor cooling application.

[0133] FIG. 19 illustrates a perspective view of a horizontally positioned very common heat sink 80 as used by millions of electronic devices. It consists of a flat surface portion 88 with a plurality of fins 89. It is predominantly made by an aluminum extrusion process or a casting process. Mounted on the surface portion 88 are several power dissipating semiconductor devices 87. Under operation these devices 87 generate heat; which heat is conductively transferred to the heat sink 80 containing a plurality of fins 89. Air currents begin to flow as described in the description of FIG. 3. As shown by arrow 86, rising air currents cannot traverse thru the bottom surface 88 of heat sink 80 and diverge around the said heat sink 80. Complex micro air currents in and around the heat sink 80 fins 89 do a reasonable job of heat transfer to the ambient air.

[0134] Now therefore, the well understood science of heat transfer teaches us that still air has an extremely low thermal conductivity of about 0.026 W/mK, depending upon altitude, barometric pressure, humidity etc. However moving air has a much better heat transfer capability. Subsequently deep in the central inner parts of the heat sink 80 little air current movement is going on, hence the inefficiency of the heat sink 80.

[0135] Now let us discuss forced air cooling of the heat sink 80. According to Langmuir's laminar flow theory, smooth and even air flow over a surface does not result in efficient heat transfer due to a “boundary layer effect” wherein the air atomically close to the surface over which the air is flowing does not move. Thus heat transfer is radiative in nature from the surface to the moving air close above the said surface. How do we overcome this? If we cause the air movement to be turbulent, heat transfer is more efficient since the turbulence disrupts the boundary layer effect to a significantly large degree by a scrubbing action of irregular atmospheric motion especially when characterized by up-and-down micro current turbulence.

[0136] Air turbulence is greatly induced when air is pushed, and is less when air is sucked thru a heat sink's fins. As explained to this inventor by a seasoned aeronautical engineer several years ago, air molecules are to be likened to light ping pong balls that refuse to be pushed in the direction of the forced air, but can be easily sucked up by a vacuum cleaner. Pushing air causes turbulence, while sucking air tends towards smoother air flow.

[0137] Now if we introduce holes or slots in the heat sinks fins, further subtle effects occur. For example, moving air over a hole or slot will pull additional air thru these said slots or holes due to the “Bernoulli effect”, further causing more air flow and turbulence due to “edge effects” thus creating better heat transfer. One type of “edge effect” occurs when moving air over an even surface suddenly passes over a sharp discontinuity on the said surface such as an edge or trough or channel etc. The moving air experiences a disruption and turbulence results, further disrupting laminar flow and convective heat transfer is augmented.

[0138] The above has been a greatly simplified explanation since a rigorous treatment of the subject would is beyond the scope if this teaching.

Eleventh Embodiment of the Present Invention

[0139] FIG. 20 illustrates a perspective view of an Eleventh Embodiment of the present invention. It consists of a horizontally positioned heat sink 90, a flat surface portion 98 with a plurality of fins 99. Mounted on the surface portion 98 are several power dissipating semiconductor devices 87. Under operation these devices 87 generate heat; which heat is conductively transferred to the heat sink 90 containing a plurality of fins 99. Air currents begin to flow; but this time thru the heat sink 90 via slots 95 as shown by arrow 96, past the exposed bottoms of the heat sink 90 fins 94. Now we have a faster air movement and cool air entering at the base of the said fins 94. This is a more efficient heat sink than the one in FIG. 19. Section D-D is removed and the remainder depicted in FIG. 21.

[0140] FIG. 21 illustrates a partial perspective sectional view of a horizontally positioned heat sink 90 as used in the present invention where the proximal section D-D depicted in FIG. 20 has been removed. It consists of a flat surface portion 98 with a plurality of fins 99. Mounted on the surface portion 98 are several power dissipating semiconductor devices 87. Under operation these devices 87 generate heat; which heat is conductively transferred to the heat sink 90 containing a plurality of fins 99. Air currents begin to flow; but this time thru the heat sink 90 via slots 95 as shown by arrows 96, past the exposed bottoms of the heat sink 90 fins 94. Now we have a faster air movement and cool air entering at the base of the said fins 94. The sectional view C-C shows the exposed fins 94 clearly. The depth of the slots 95 is just deep enough to expose the bottoms on the Fins 90. This is a more efficient heat sink than the one depicted in FIG. 19. Also, as noted earlier in these teachings, slots were shown on the heat sink 90. Holes or other shape of openings may be used depending on the engineer's design constraints and are hereby incorporated by reference.

[0141] As a note, the heat sinks 90 as depicted in FIGS. 20 and 21 do not have to be in a horizontal position; they are more efficient than heat sink 80 in other orientations. In the vernacular, we have allowed the heat sink 90 to “breathe” better.

Twelfth Embodiment of the Present Invention

[0142] FIG. 22 illustrates a Twelfth Embodiment of the present invention. It is a perspective view of a horizontally positioned heat sink 100 as used in the present invention. It consists of a flat surface portion 108 with a plurality of fins 104 and a plurality of holes 105 drilled deep enough to expose the bottoms of fins 104. Mounted on the surface portion 108 are several power dissipating semiconductor devices 87. Under operation these devices 87 generate heat; which heat is conductively transferred to the heat sink 100 containing a plurality of fins 104 with holes 105. Air currents begin to flow; but this time thru the heat sink 100 via holes 105, past the exposed bottoms of the heat sink 100 fins 104. Now we have a faster air movement and cool air entering at the base of the said fins 104. This is a more efficient heat sink than the one in FIG. 19. FIG. 22 also shows additional side holes 205 being added to fins 104 for more efficiency. The side holes, which are drilled just above the base portion 106, can be drilled thru all the fins 104 or only a selected few as desired. Once again it is recommended that the heat sink's surface maintains the same area or more if possible.

Thirteenth Embodiment of the Present Invention

[0143] FIG. 23 illustrates a Thirteenth Embodiment of the present invention. It is a perspective view of a horizontally positioned heat sink 300 with fins 304 as used in the present invention. This is a variant of the heat sink of FIG. 23 with LED devices 387 mounted on flat surface 308. This is a useful device for non-room lighting such as embedded lighting for industrial applications and machine interior inspection or machine operating etc.

Fourteenth Embodiment of the Present Invention

[0144] FIG. 24 illustrates a Fourteenth Embodiment of the present invention. It is a perspective view of a horizontally positioned double sided heat sink 400 with fins 404 positioned on each side of base 406. A flat base portion 407 is used to mount either power LEDs or power semiconductors (not shown) as used in the present invention. This is a heat sink for specialty applications. In cases where side drilling is not desired and partial drilling of one sided finned heatsinks is also not wanted, an alternate is now offered. Thru-drilling in the interstitial gaps between the heat sink fins can be done to achieve good results. The next figure will show section E-E removed.

[0145] FIG. 25 illustrates view E-E of FIG. 26 showing holes 410 aligned with interstitial gaps between the heat sink fins 404. As shown by arrow 410 (and dashed line at point of arrow 410 showing hole alignment), FIG. 25A is a magnified view F-F of FIG. 25 showing the holes 412 thru base 406. Note dashed line 413 indicating alignment of holes 412 with the said interstitial spaces between the said heatsink fins 404.

Fifteenth Embodiment of the Present Invention

[0146] FIG. 26 illustrates a Fifteenth Embodiment of the present invention. It is a perspective view of a horizontally positioned double sided heat sink 500 with fins 504 positioned on each side of base portion 506. A flat portion 507 both top and bottom is used to mount either power LEDs or power semiconductors (not shown) as used in the present invention. This is a heat sink for higher power dissipation capability. Holes 505 are shown. These said holes are drilled large enough to expose the bases of fins 504, and deep enough to expose the fins save the last fins 504a and 504b for cosmetic purposes and not to interfere with the flat portions 507. The next figure will show section G-G removed.

[0147] FIG. 27 illustrates the heat sink of FIG. 26 with section G-G removed. Note the exposed fins 510 caused by the drilled holes as described in FIG. 26. During operation, this heatsink now has air moving in a short path straight thru the double fins 504 since the base 506 portions have been drilled out. Air flow as represented by arrow 596 shows this clearly. Once again it is recommended that the heat sink's surface maintains the same area or more if possible.

Sixteenth Embodiment of the Present Invention

[0148] FIG. 28 illustrates side view of a Sixteenth Embodiment LED light fixture 600 of the present invention. This is a high power luminaire as would be used in tall warehouses, lamp posts, stadiums, school gymnasiums, etc. These exclusively use high power LEDs and generally come in 200 watt to 500 watt units and up units.

[0149] The illustration in FIG. 28 shows a generally circular luminaire but is not limited to this style. A perimetrical structure such as is used in some modern street lights and commercial wall lights etc. is also possible.

[0150] Cooling is a massive task; as is water proofing and internal prevention of moisture build up. The said luminaire consists of a large one piece heatsink 640 with fins 641 and a flat base 650. Mounted on the bottom of base 650 is a highly heat conductive (such as copper) heat spreader 662 of special design. A plurality of high power LEDs 660 is mounted on said heat spreader 662. A transparent/translucent cover 670 is provided and an optional large reflector 680 is shown.

[0151] Although the said fins 641 are shown to be on the top only, some extra fins could also be placed on selected areas on the bottom (not shown) side also and are hereby incorporated by reference.

[0152] To give the reader an idea of size, the heat sink 650 can be as large as a foot (305 mm) or more in diameter. Sitting above heat sink 640 is a central hub section containing a power supply and other optional devices such as, for example ambient light sensors, wired or wireless communication devices etc., with attached “eye Bolt” 610 for mounting purposes. Side bolts 622 are also provided for alternate mounting methods as well.

[0153] FIG. 29 illustrates a front face view of heat sink 640 with LED assembly. Slots 630 are milled thru base 650 shown in FIG. 28 exposing the bottom parts of heatsink 640 fins 642. Note circular section H-H.

[0154] FIG. 30 illustrates a magnified view section H-H of FIG. 29. Slots 630 are visible and exposed fin sections 642 are clearly shown. Why is this heatsink efficient? The thick base 650 (FIG. 28) conducts the intense heat flux radially outward very fast and the fins 641 sections dissipate the said heat efficiently due to the cooling air moving thru the slots and directly around the fins and subsequently up into the ambient environment. The cooling air first strikes the hottest part of the heatsink fins and then follows a short path up and out, dragging new cooling air up with it. If even higher power LED lighting is desired, the base portion 650 can be made of copper which has twice the thermal conductivity of aluminum, while the fins are still aluminum. The idea is to conduct the heat out of the middle portion where the LEDs are located as quickly as possible. Additionally, graphene layer/s could be added within the base portion 650 for even faster heat conduction and is hereby incorporated by reference.

Seventeenth Embodiment of the Present Invention

[0155] FIG. 31 illustrates a Seventeenth Embodiment of the present invention. It is a front face view only of an alternate heat sink and LED assembly for the luminaire shown in FIG. 28. The heatsink of this embodiment is a six part unit, pie shaped in this illustration, but not limited to said shape, and assembled together as shown. One segment is shown jutting out for clarity of description. This method of constructing the luminaire heat sink/LED assembly is advantageous for two reasons. First we are working with a smaller assembly and second, field replacement of sections of the LED/heatsink assemblies is easier than working on the whole massive unit. Indeed making each section pluggable would make field repair easy. Additionally, each said section could have its own smaller power supply which is cheap and adds further redundancy to power supply reliability. If one fails, the other five segments would still provide light. There are a variety ways to practice this invention and are hereby incorporated by reference.

Led Lighting Devices—Short Description

[0156] LED lighting is fast becoming as ubiquitous as the incandescent bulb was in the last century. Worldwide, manufacturers and lighting contractors are trampling over each other to get a piece of the action in this business. Generally, LEDs for lighting purposes come in three classes and two types within those classes. [0157] Class 1—Low power LEDs—less than 1 Watt dissipation. [0158] Class 2—High power LEDs—greater than 1 Watt dissipation. [0159] Class 3—Very High power multi-chip LED assemblies—greater than 10 Watts dissipation and supremely difficult to cool.
The two types in class 1 and class 2 are: [0160] 1. Wide angle luminance, about 100-165 degrees in a scattered fashion due to a flat LED emitting face. [0161] 2. Narrow angle luminance, about 20-60 degrees typically in a Lambertian distribution due to a molded-in lens.
Class 3 devices can be narrow angle up to about 5 watts while higher power units use a plurality of individual chips mounted as an array in one package with a common phosphor applied over the entire said LED chip array and so a narrow angle is more difficult. Indeed, multi-chip units are being made with up to 100 watts dissipation and more. They are supremely difficult to cool with ambient air since the small area heat flux from the multi-chip modules is extremely high. Even solid copper heat transfer is tenuous at best. Forced air cooling is greeted with contempt by customers due to the noise, low reliability and dust accumulation of fans. Dust is impinged upon heat sink fins due to the orders of magnitude greater air flow passing over the said heat sink fins as compared to normal non-forced air flow.

[0162] LEDs used in the present invention are mostly of the low power type because they are individually inexpensive and are thermally manageable. A typical fixture of the present invention can use dozens of low power LED devices, each with less than one watt dissipation. However, the present invention does accommodate high power LED technology since the market demands it.

[0163] FIG. 32 illustrates a sectional view of a low power surface mount LED 100 with wide angle characteristics. It consists of a housing 110, a copper lead frame 111, upon which is bonded a light emitting silicon chip 112. A wire bond 115 connects the top section of chip 112 to the other lead 111 (left copper lead in FIG. 22). A rather large phosphor fill 114 is provided which emits white light. The copper leads 111 provide conductive heat transfer to a printed circuit board (not shown) on which the LED 100 is soldered.

[0164] FIG. 33 illustrates a sectional view of a low power surface mount LED 120 with narrow angle characteristics. It consists of a housing 115, a copper lead frame 131, upon which is bonded a light emitting silicon chip 132. A wire bond 134 connects the top section of chip 132 to the other lead 131 (left copper lead in FIG. 33). Unlike in the wide angle LED shown in FIG. 32, a relatively compact phosphor covering 124 surrounds the chip which emits white light in an intense almost point source configuration. A molded focusing lens 119 is also provided. The lens 119 in combination with the mentioned small phosphor 124 the light emission angle considerably. The copper leads 131 provide conductive heat transfer to a printed circuit board (not shown) on which the LED 110 is soldered.

[0165] FIG. 34 illustrates a sectional view of a power surface mount LED 130 with narrow angle characteristics. It consists of a housing 135, a copper lead frame 141, upon which is bonded a light emitting silicon chip 142. A wire bond 146 connects the top section of chip 142 to the other lead 141 (left copper lead in FIG. 34). Unlike in the wide angle LED shown in FIG. 32, a relatively compact phosphor covering 134 surrounds the chip which emits white light in an intense almost point source configuration. A molded focusing lens 129 is also provided. The lens 129 in combination with the mentioned small phosphor 144 narrows the light emission angle considerably. The copper leads 141 provide conductive heat transfer to a printed circuit board (not shown) on which the LED 130 is soldered. Additionally, a copper or other highly conductive material slug 145 removes heat from the silicon chip directly to the exposed bottom portion of LED 130 which can be soldered to a PCB as well as the leads 141.

[0166] High power LEDs use a great variety of mounting methods from large area solder flow to directly bolting to a big heatsink.

SUMMARY RAMIFICATIONS AND SCOPE

[0167] The fixtures described in this teaching provide the installation professional several advantages, some of which are summarized as follows:

[0168] 1. Low cost.

[0169] 2. Universal mounting positions.

[0170] 3. Minimum installation labor.

[0171] 4. Retrofit versatility.

[0172] 5. Light weight.

[0173] 6. Low power consumption.

[0174] A hidden feature of LED light fixtures is that these fixtures can be made to produce white, red, green, blue or yellow light. For example a yellow or red light fixture may be used in a chemistry lab or photo processing lab where white light is not desired. Indeed the same fixture could be made to have two or more color LEDs so that one fixture can perform both jobs as necessary. This was not easily done with fluorescent light fixtures of the past. Furthermore RGB LED lights can produce a variety of colors necessary by controlling the power to each of the three led devices. Generally this is done using Pulse Width Modulation techniques which will not be described here since it is well understood in the art. These features can be controlled remotely by Power Line Signal or Optical Signal or Radio Frequency Signal means. They will not be described since they also are well known in the art. These control devices are available on the commercial market as complete modules. Most are covered by their own patent portfolios; thus this disclosure does not claim their technology, but does claim the use of these said control devices in the specific environment of LED devices described herein.

[0175] RGB LEDs can also be used for white light variations such a “warm white” for winter and a “cool white” for summer etc. (“Warm white” is a lower color temperature tending towards the yellow whereas a “cool white” is a higher color temperature tending towards the blue.). None of the described embodiments showed built-in ballasts/power supplies. Although they were not described, the present invention does not preclude their use as a built in device but has omitted them for clarity of the teaching

[0176] This inventor claims these aspects of the novelty and the claims section of this patent reflect this clearly. Although the descriptions above contain a number specificities these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of this invention. Thus the scope of the invention should be determined by the appended claims and their legal equivalents rather than by the examples provided.

[0177] The claims are not limited to the various aspects of this disclosure, but are to be afforded the full scope consistent with the language of the claims. Structures and functional equivalents of the elements of the various aspects described throughout this disclosure that are known or are later come to be known to those skilled in the art are expressly incorporated herein by reference and are intended to be encompassed by metes and bounds of the claims. Additionally, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. §112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or in the case of a method claim, the element is recited using the phrase “step for”.