System and method for heat dissipation from an automotive lighting assembly having a liquid cooling circuit
View Patent ↗An automotive headlamp assembly having a closed-loop cooling circuit. The headlamp assembly includes a housing cooperating with a transparent lens cover to define a chamber. At least one light source is located within the chamber. The cooling circuit has at least one cold plate thermally coupled to the light source. A radiator is fluidly coupled to the cold plate by a plurality of tubes. The tubes are oriented at least partially upwardly and configured to circulate a fluid through the cooling circuit as a result of heating and cooling of the fluid therein.
1. An automotive headlamp assembly for a motor vehicle comprising:
a housing having a housing wall defining an opening;
a transparent lens cover coupled to the housing wall and covering the opening, the housing and the lens cooperating to define a chamber;
at least one light source located within the chamber;
a reflector positioned within the chamber and adapted to reflect light from the light source out of the chamber through the lens; and
a closed-loop cooling circuit comprising:
at least one cold plate, the cold plate being thermally coupled to the light source;
at least one radiator; and
a plurality of tubes connecting the cold plate to the radiator, the tubes at least partially vertically oriented relative to the vehicle and configured to circulate a fluid through the cooling circuit as a result of heating of the fluid by the cold plate and cooling of the fluid by the radiator.
2. The headlamp assembly of claim 1 wherein the cold plate defines a cold plate channel having a cold plate inlet and a cold plate outlet, the cold plate outlet being located above the cold plate inlet relative to the motor vehicle.
3. The headlamp assembly of claim 1 wherein the radiator defines a radiator channel having a radiator inlet and a radiator outlet, the radiator inlet being located above the radiator outlet relative to the motor vehicle.
4. The headlamp assembly of claim 1 wherein the at least one cold plate includes a plurality of cold plates, wherein the plurality of cold plates is connected in series by the plurality of tubes.
5. The headlamp assembly of claim 1 wherein the at least one cold plate includes a plurality of cold plates, wherein the plurality of cold plates is connected in series with the radiator by the plurality of tubes.
6. The headlamp assembly of claim 1 wherein the at least one light source includes a plurality of light sources, wherein the plurality of light sources includes at least one light emitting diode.
7. The headlamp assembly of claim 1 wherein the radiator is disposed within the chamber.
8. The headlamp assembly of claim 1 wherein the radiator is disposed outside of the chamber.
9. The headlamp assembly of claim 1 wherein at least one of the tubes is more thermally conductive than at least one other of the tubes.
10. The headlamp assembly of claim 1 wherein at least one of the tubes is more thermally insulative than at least one other of the tubes.
11. The headlamp assembly of claim 1 wherein the cooling circuit includes a pump to increase the flow rate of the fluid circulating within the circuit.
12. The headlamp assembly of claim 1 wherein the number of tubes is equal to the number of cold plates plus the number of radiators.
13. The headlamp assembly of claim 2 wherein the cold plate is oriented in a generally upright orientation relative to the motor vehicle such that the cold plate channel extends from the cold plate inlet generally upwardly, relative to the motor vehicle, to the cold plate outlet.
14. The headlamp assembly of claim 3 wherein the radiator is oriented in a generally upright orientation relative to the motor vehicle such that the radiator channel extends from the radiator inlet generally downwardly, relative to the motor vehicle, to the radiator outlet.
15. A method of dissipating heat inside a headlamp assembly of a motor vehicle, wherein the headlamp assembly includes a closed-loop cooling circuit having a plurality of cold plates each coupled to at least one light source, a radiator, and a plurality of tubes fluidly connecting the cold plates to the radiator, the method comprising the steps of:
providing a flow of fluid in the cooling circuit;
collecting heat from one of the light sources and transmitting the heat to the fluid via one of the cold plates;
passing the heated fluid from one of the cold plates generally upward, relative to the motor vehicle, to a second one of the cold plates;
transferring the heated fluid from the second one of the cold plates to the radiator;
cooling the heated fluid in the radiator;
passing the cooled fluid generally downward, relative to the motor vehicle, through the radiator;
transferring the cooled fluid from the radiator to a first one of the cold plates; and
whereby the heating and cooling of the fluid in the cooling circuit causes circulation of the fluid through the cooling circuit.