Patent Application
20050047170
Light emitting diode (“LED”) light sources are desirable for use in the automotive industry because of increased efficiency and longevity over traditional incandescent or arc discharge light sources. The LED offers a better conversion of electricity to emitted light than traditional light sources used in the automotive industry. Given the increased conversion of an LED, a smaller light source and less electricity may be used to fulfill the same lighting requirement as a larger and less efficient incandescent bulb. The use of LED light sources therefore reduces demand on the automobile's alternator and electrical system, which increases the efficiency of the overall automobile. The LED light source is also much more durable and longer lasting than an incandescent or arc discharge lamp. The LED light source, while more efficient than a similar incandescent or arc discharge light source, still produces a great deal of thermal energy as a byproduct of light emission. Therefore, a heat sink may be required to prevent damage to the LED light source over prolonged use.
Modern automobiles utilize an electrical connector and socket arrangement for attaching light sources inside of lamp housings. Examples of automotive lamp housings include headlamps and tail lamps. The connector and socket hole arrangement typically provides a friction fit or a locking mechanism to securely affix the light source into the lamp housing. Automobile manufactures typically utilize one of the many types of standard connector and socket hole arrangements available, to utilize existing light sources in an effort to reduce manufacturing costs. A desirable feature of an LED light source would be the utilization of one or more of these standard connector arrangements, and to position the LED light source similarly to the incandescent light source in the socket hole. Utilizing a standard socket arrangement would allow automobile consumers to replace existing incandescent light sources with LED light sources in an aftermarket setting. Also, manufacturers could simply use LED light sources instead of incandescent light sources, without redesigning an automobile's electrical system.
Thus, desirable features of an LED lamp assembly include attaching a standard connector assembly to the LED, positioning the light source similarly to a comparable incandescent or arc discharge lamp assembly, and including a heat sink to dissipate the heat produced by the LED light source.
An LED heat sink assembly comprises a connector base, a first heat sink, and a first light emitting diode. The connector base is dimensioned to fit into one of the many socket hole assemblies available for automobiles. The first heat sink is attached to the connector base. The first heat sink is formed from a thermally conductive material, and comprises a plurality of holes formed by a plurality of ribs, allowing the dissipation of heat away from the first heat sink. The first light emitting diode is attached to the first heat sink, and is in electrical communication with the automobile's electrical system via the connector base. The connector base is adapted to fit any one of the many socket hole assemblies available for automobiles. A second heat sink may be formed with the first heat sink or attached to the heat sink separately. A second light emitting diode is attached to the second heat sink, and is in electrical communication with the automobile's electrical system. The first light emitting diode and the second light emitting diode receive electricity from the automobile's electrical system via the connector base. Light is emitted from the energized light emitting diodes.
In an alternate embodiment, the second heat sink is pivotably attached to the first heat sink, where the pivot may be locked using a screw. The second heat sink may also be releasably attached to the first heat sink, and may be removed or attached as desired.
These and other advantages and features of the present invention shall hereinafter appear, and for the purposes of illustration, but not limitation, exemplary embodiments of the present invention shall hereinafter be described.
One embodiment of a LED heat sink assembly is provided as shown in
The connector element 20 provides an electrical attachment point to the automobile's electrical system, and is designed to fit into a standard automotive lamp socket 60 (see
The heat sink 24 is attached to the electrical connector element 20, and is formed from a rigid thermally conductive material, such as aluminum. Fasteners 21 are inserted into overlapping openings in the heat sink base 22 and the electrical connector element 20, to secure the heat sink 24 to the electrical connector element 20. The heat sink 24 may be constructed with openings 27 therethrough, to facilitate the transfer of beat from the heat sink to the surrounding atmosphere. The openings 27 are formed by the plurality of ribs 29 that form heat dissipating surfaces for the heat sink. It should be noted that any pattern of openings in the heat sink 24 may be used, as known in the art. The openings in the heat sink 24, as well as the dimensions and material used, may vary depending on use, in order to optimize heat transfer to the surrounding atmosphere and to optimally position the LED light source 28 inside of the lamp 0housing (not shown). The heat sink attachment plate 25 is also formed from a rigid thermally conductive material, and is attached to the ribs of the heat sink 24. The heat sink base 22, ribs 29 and plate 25 may all be a single integral piece, or may be constructed as multiple connected pieces.
The LED attachment plate 26 is also formed from a rigid thermally conductive material, and is attached in thermal communication with the heat sink attachment plate 25. The heat sink 24 and the LED attachment plate 26 may all be formed as a single component, or they may be formed separately, and attached together by welding or any other means known in the art. If the above components are formed separately, a thermally conductive paste may be used to enhance heat transfer between the components. The LED attachment plate 26 contains an opening which serves as an attachment point for one or more LED light sources 28.
The LED light source 28 is attached to the LED attachment plate 26, and is in electrical communication with the automobile's electrical system via wires (not shown) extending from the electrical connector element 20, through or along the heat sink 24, and into the leads to the LED provided on the LED attachment plate 26. The LED light source 28 may be formed from any combination of materials, such that it may emit light of any color, as is known in the art. The LED light source 28 may also be operable to emit light of any intensity, as different automobile lighting requirements may necessitate that the LED light source or light sources be of a specific intensity or in a specific range of intensities.
For some automotive lighting applications, additional lighting may be required or desired, or an alternate light source position may be desired. Such an addition may be made by attaching a second heat sink assembly 50 to the attachment plate 25, as described below and as shown in
In one alternate embodiment, the attachment point 48 may be provided as a hinged joint that may be locked in place by rotation of a screw (not shown) in an adjustment hole (not shown) provided on the attachment point. When the screw is loosened, the LEDs may be adjusted relative to each other within the lamp assembly.
In another alternate embodiment, the attachment point 48 may be provided as a detachable structure, so that the second heat sink assembly 50 may be attached or detached as desired. The two structures may be affixed to each other by the use of a screw (not shown).
Operation of the disclosed embodiment of a LED heat sink assembly 18 is now described in
Once installed in the automobile, the LED heat sink assembly 18 may be selectively energized. Energizing the LED heat sink assembly 18 transmits electricity to the LED light source 28 and the second LED light source 46, if a second heat sink assembly 50 is attached. The energized LED light sources 28 and 46 then emit light into the lamp housing (not shown). The use of the second heat sink assembly 50 allows additional lighting, and the first and second heat sinks 24 and 40 allow heat produced by the first and second LED light sources 28 and 46 to be transferred away from the assembly, an important function required for prolonged use.
As can be readily seen, utilization of the present invention allows a LED light source to be used as a replacement for an incandescent lamp in automobile lighting applications. Thus, utilizing the present invention with an automobile decreases the electrical demands and increases the useful life of the lamp, while still utilizing the original geometry of the lamp reflector, and also providing thermal dissipation for the light source.
Although other advantages may be found and realized and various modifications may be suggested by those versed in the art, it is understood that the present invention is not to be limited to the details given above, but rather may be modified within the scope of the appended claims.
