COOLING DEVICE FOR VEHICLE HEADLIGHTS

• US 20150098235A1
• Filed: 10/06/2014
• Published: 04/09/2015
• Est. Priority Date: 10/09/2013
• Status: Active Grant

• Current Assignee: Fujikura Limited
• Original Assignee: Fujikura Limited
• Inventors: SINGH, Randeep, MOCHIZUKI, Masataka
• Granted Patent: US 9,188,305 B2
• Time in Patent Office: Days
• US Class Current: 362/516
• CPC Class Codes: F21S 41/148 the main emission direction of the LED being perpendicular to the optical axis
• CPC Class Codes: F21S 41/151 arranged in one or more lines
• CPC Class Codes: F21S 41/155 Surface emitters, e.g. organic light emitting diodes [OLED]
• CPC Class Codes: F21S 41/32 Optical layout thereof
• CPC Class Codes: F21S 41/321 the reflector being a surface of revolution or a planar surface, e.g. truncated
• CPC Class Codes: F21S 45/435 circulating the gas within a closed system
• CPC Class Codes: F21S 45/47 Passive cooling, e.g. using fins, thermal conductive elements or openings
• CPC Class Codes: F21S 45/49 Attachment of the cooling means

Abstract

A cooling device for cooling an LED of vehicle headlight without restricting a design of a housing is provided. The cooling device is comprised of an LED held in a housing sealed with a lens, a reflector that reflects a light emitted from the light source, a heat collector on which the LED is mounted, a heat sink disposed behind the reflector, and a pair of heat pipes thermally connecting the heat collector and the heat sink. The heat sink is arranged inside of the housing.

Claims

1. A cooling device for vehicle headlights, comprising:

an LED light source held in a housing sealed with a lens;

a reflector that reflects a light emitted from the LED light source;

a heat sink that is disposed behind the reflector;

a heat pipe that transports heat generated by the LED light source to the heat sink by a working fluid encapsulated therein;

a flat cuboid vapor chamber that serves as a heat collector on which the LED light source is mounted;

wherein the heat sink is comprised of a base covering the reflector from behind and above while keeping a distance therebetween, and a plurality of fins erected vertically to extend from the base in the opposite side of the reflector;

wherein a surface area of lower section of the fin is smaller than that of an upper section;

wherein the heat pipe includes

a first heat pipe in which one of end portions is flattened to be contacted with a front long side of the vapor chamber, and the other end portion penetrates through the upper section of the fin while being contacted therewith, and

a second heat pipe in which one of end portions is flattened to be contacted with a rear long side of the vapor chamber, and the other end portion penetrates through the upper section of the fin while being contacted therewith; and

wherein the reflector is isolated from the vapor chamber and the heat pipes.

2. The cooling device for vehicle headlights as claimed in claim 1, wherein the vapor chamber is comprised of:

a sealed container;

a working fluid held in the container; and

a wick that performs a capillary action.

3. The cooling device for vehicle headlights as claimed in claim 1, further comprising:

a piezo fan that cools the LED light source by sending air over the LED light source;

wherein the piezo fan is disposed at a site not to block an incident light to the reflector emitted from the LED light source.

4. The cooling device for vehicle headlights as claimed in claim 1,

wherein each of the first and the second heat pipe is further comprised of a branch contacted with an inner face of the housing;

and

wherein said one of the end portion serves as an evaporating portion, said other end portion serves as a condensing portion, and the branch serves as another condensing portion.

5. The cooling device for vehicle headlights as claimed in claim 2, further comprising:

a piezo fan that cools the LED light source by sending air over the LED light source;

wherein the piezo fan is disposed at a site not to block an incident light to the reflector emitted from the LED light source.

6. The cooling device for vehicle headlights as claimed in claim 2,

wherein each of the first and the second heat pipe is further comprised of a branch contacted with an inner face of the housing;

and

wherein said one of the end portion serves as an evaporating portion, said other end portion serves as a condensing portion, and the branch serves as another condensing portion.

7. The cooling device for vehicle headlights as claimed in claim 3,

wherein each of the first and the second heat pipe is further comprised of a branch contacted with an inner face of the housing;

and

wherein said one of the end portion serves as an evaporating portion, said other end portion serves as a condensing portion, and the branch serves as another condensing portion.

8. The cooling device for vehicle headlights as claimed in claim 5,

wherein each of the first and the second heat pipe is further comprised of a branch contacted with an inner face of the housing;

and

wherein said one of the end portion serves as an evaporating portion, said other end portion serves as a condensing portion, and the branch serves as another condensing portion.