LED light bulbs
View Patent ↗LED light bulbs include openings in base or cover portions, and optional forced flow elements, for convective cooling. Thermally conductive optically transmissive material may be used for cooling, optionally including fins. A LED light engine may be fabricated from a substrate via planar fabrication techniques and shaped to form a substantially rigid upright support structure. Mechanical, electrical, and thermal connections may be made between a LED light engine and a LED light bulb.
1. A light emitting diode (LED) light bulb comprising:
a LED light engine including a substrate having patterned thereon at least one electrical trace, wherein the substrate includes at least one bend to form multiple non-coplanar LED support surface portions to which multiple LEDs are mounted;
a base element including multiple electrical contacts arranged near a base end;
a light-transmissive cover defining an interior volume in which the multiple LEDs of the LED light engine are contained;
an externally accessible heatsink associated with the base element and arranged between the base end and the cover;
wherein the LED light engine is mated with the base element to make mechanical, electrical, and thermal connections to the base element.
2. A LED light bulb according to claim 1 , wherein the at least one electrical trace comprises a plurality of electrical traces.
3. A LED light bulb according to claim 1 , wherein the base end comprises an Edison-type threaded light bulb connector including a lateral electrical contact and a foot electrical contact.
4. A LED light bulb according to claim 1 , wherein the base end comprises a threaded contact-defining end cap arranged to mate with a threaded electrical socket.
5. A LED light bulb according to claim 1 , further comprising one or more electrical control circuit elements arranged in the base element.
6. A LED light bulb according to claim 5 , wherein the one or more electrical control circuit elements comprises any of a LED drive circuit element and a LED control circuit element.
7. A LED light bulb according to claim 1 , wherein the externally accessible heatsink comprises a plurality of fins arranged to dissipate heat generated by the multiple LEDs.
8. A LED light bulb according to claim 1 , wherein the substrate comprises a metal core printed circuit board, or comprises a stamped metal layer and at least one electrically insulating layer.
9. A LED light bulb according to claim 1 , further comprising at least one compression fitting arranged to promote mounting between the LED light engine and the base element.
10. A LED light bulb according to claim 1 , wherein at least one support surface portion of the LED light engine comprises at least one edge connector portion arranged to promote connection between the LED light engine and the base element.
11. A LED light bulb according to claim 1 , wherein the cover comprises any of a diffuser and a lens.
12. A LED light bulb according to claim 1 , wherein the cover comprises a lumiphoric material.
13. A LED light bulb according to claim 1 , wherein the cover comprises a plurality of openings to enable air or other fluid to flow between the interior volume and an ambient environment.
14. A LED light bulb according to claim 1 , wherein at least a portion of the cover comprises a material having visible spectrum transmittance of least about 80% and a thermal conductivity of at least 25 W/(m·° K) at about 25° C., and the cover is in conductive thermal communication with the multiple LEDs.
15. A light fixture comprising the LED light bulb of claim 1 .
16. A method for fabricating the LED light bulb of claim 1 , the method comprising:
patterning a substantially planar substrate to define at least one electrical trace for multiple LEDs;
mounting multiple LEDs to the substrate in electrical communication with the at least one electrical trace; and
shaping the substrate to define at least one bend therein to form multiple non-coplanar LED support surface portions to which the multiple LEDs are mounted.
17. The method of claim 16 , wherein the shaping of the substrate is performed after the mounting of the multiple LEDs to the substrate.
18. The method of claim 16 , wherein following the shaping step, the method further comprises mating the substrate with the base element to make mechanical, electrical, and thermal connections to the base element.
19. The method of claim 16 , further comprising mounting to, defining in, or defining on the substrate the at least one of a LED drive circuit element and a LED control circuit element.
20. A light emitting diode (LED) light bulb comprising:
a cover defining an interior volume, wherein at least a portion of the cover comprising a material having visible spectrum transmittance of least about 80% and a thermal conductivity of at least 25 W/(m·° K) at about 25° C.; and
a substrate supporting at least one LED, wherein the at least one LED and at least a portion of the substrate are disposed within the interior volume.
21. The LED light bulb of claim 20 , wherein said material has a thermal conductivity of at least about 100 W/(m·° K) at about 25° C.
22. The LED light bulb of claim 21 , wherein the cover comprises a plurality of fins.