COOLING DEVICE FOR AN AUTOMOTIVE LUMINOUS DEVICE

Abstract

A cooling device for cooling a light source located in an automotive luminous device. This cooling device includes a heat sink intended to be in thermal contact with the light source, a plurality of fins in direct thermal contact with the heat sink, a plurality of pins in direct thermal contact with the heat sink and a fan. The fan is arranged to make a fluid flow from an inlet of the cooling device to an outlet to the cooling device, so that the plurality of fins are nearer the inlet than the plurality of pins.

Claims

1. Cooling device for cooling a light source located in an automotive luminous device, the cooling device comprising a heat sink intended to be in thermal contact with the light source, a plurality of fins in direct thermal contact with the heat sink; a plurality of pins in direct thermal contact with the heat sink; a fan arranged to make a fluid flow from an inlet of the cooling device to an outlet to the cooling device, so that the plurality of fins are nearer the inlet than the plurality of pins.

2. Cooling device according to claim 1, wherein the fan is nearer the inlet than the plurality of fins.

3. Cooling device according to claim 1, wherein the fan is nearer the outlet than the plurality of pins.

4. Cooling device according to claim 1, wherein when the fluid is moved by the fan, it is intended to enter the inlet of the cooling device in a first direction and is intended to exit the plurality of pins in a second direction which is substantially equal to the first direction.

5. Cooling device according to claim 1, wherein the plurality of fins and the plurality of pins protrude from the heat sink.

6. Cooling device according to claim 5, wherein the plurality of fins and the plurality of pins form the same angle with the heat sink.

7. Cooling device according to claim 6, wherein the plurality of pins have a frustoconical shape and the plurality of fins have a base and a top portion narrower than the base.

8. Cooling device ROM according to claim 1, further comprising a first and second walls protruding from the heat sink in such a way that the plurality of fins and the plurality of pins are enclosed by the first and second walls; a plenum wall located opposite to the heat sink, so as to form a closed duct with the heat sink and the first and second walls.

9. Cooling device according to claim 1, wherein the plurality of pins are arranged in at least four offset rows of pins, resulting a quincunx arrangement.

10. Cooling device according to claim 9, wherein each fin is straight and define a fin line as the prolongation of the fin, in such a way that all the fin lines are parallel; the rows of pins are parallel to the fin lines, but the fin lines do not coincide with the rows of pins.

11. Cooling device according to claim 10, wherein the distance between two adjacent pins is comprised between 3 and 6 mm; the distance between two adjacent fins is comprised between 4 and 6 mm; and the distance between a fin and its closest pin is comprised between 3 and 5 mm.

12. Automotive luminous device comprising a cooling device according to claim 1; and a light source arranged in thermal contact with the heat sink.

13. Automotive luminous device according to claim 12, further comprising a first optical element arranged to receive light from the light source and to shape the light into a light pattern projected outside the luminous device.

14. Automotive luminous device according to claim 13, wherein the optical element is at least one of a lens, a light guide, a reflector or a collimator.

15. Automotive luminous device according to claim 12, wherein the light source is a solid-state light source, and in particular a light emitting diode or LED.

16. Cooling device according to claim 2, wherein the plurality of fins and the plurality of pins protrude from the heat sink.

17. Cooling device according to claim 2, further comprising a first and second walls protruding from the heat sink in such a way that the plurality of fins and the plurality of pins are enclosed by the first and second walls; a plenum wall located opposite to the heat sink, so as to form a closed duct with the heat sink and the first and second walls.

18. Cooling device according to claim 2, wherein the plurality of pins are arranged in at least four offset rows of pins, resulting a quincunx arrangement.

19. Automotive luminous device according to claim 13, wherein the light source is a solid-state light source, and in particular a light emitting diode or LED.

20. Cooling device according to claim 3, wherein the plurality of fins and the plurality of pins protrude from the heat sink.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] To complete the description and in order to provide for a better understanding of the invention, a set of drawings is provided. Said drawings form an integral part of the description and illustrate an embodiment of the invention, which should not be interpreted as restricting the scope of the invention, but just as an example of how the invention can be carried out. The drawings comprise the following figures:

[0037] FIG. 1 shows a particular embodiment of a cooling device according to the invention.

[0038] FIG. 2 shows a more detailed view of such a cooling device.

[0039] FIG. 3 shows the automotive lighting device shown in the previous figures mounted on an automotive vehicle.

DETAILED DESCRIPTION OF THE INVENTION

[0040] The example embodiments are described in sufficient detail to enable those of ordinary skill in the art to embody and implement the systems and processes herein described. It is important to understand that embodiments can be provided in many alternate forms and should not be construed as limited to the examples set forth herein.

[0041] Accordingly, while embodiment can be modified in various ways and take on various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. There is no intent to limit to the particular forms disclosed. On the contrary, all modifications, equivalents, and alternatives falling within the scope of the appended claims should be included. Elements of the example embodiments are consistently denoted by the same reference numerals throughout the drawings and detailed description where appropriate.

[0042] Unless otherwise defined, all terms (including technical and scientific terms) used herein are to be interpreted as is customary in the art. It will be further understood that terms in common usage should also be interpreted as is customary in the relevant art and not in an idealised or overly formal sense unless expressly so defined herein.

[0043] In this text, the term comprises and its derivations (such as comprising, etc.) should not be understood in an excluding sense, that is, these terms should not be interpreted as excluding the possibility that what is described and defined may include further elements, steps, etc.

[0044] FIG. 1 shows a perspective front view of a particular embodiment of a cooling device 1 according to the invention. This cooling device 1 is intended to be part of a headlamp and comprises a heat sink 2 which is in thermal contact with a plurality of LEDs which provide a light beam functionality.

[0045] FIG. 2 shows a cut view of such a cooling device 1, so that the elements contained in the cooling device 1 may be seen. This cooling device comprises an inlet 11 for air intake and an outlet 12 for air exit.

[0046] Firstly, the cooling device 1 of this figure comprises a plurality of fins 3 which directly protrude from the heatsink 2. As may be seen in this figure, all of these fins 3 are parallel and each one defines a fin line 30 as the prolongation of their shapes.

[0047] Secondly, this cooling device 1 further comprises a plurality of pins 4 which directly protrude from the heatsink 2. As may be seen in this figure, all of these fins 3 protrude from the heat sink and are arranged in rows. These rows are offset, thus forming a quincunx arrangement. Further, each row is located between two different fin lines 30, so as not to coincide with any of them.

[0048] Finally, this cooling device comprises a fan 6. This fan is located at the outlet 12 of the cooling device 1 so that, when the cooling device 1 is in operation, air is sucked from the fan, and is forced to cross the fins, then the pins, then the fan and then exits the cooling device.

[0049] The linear arrangement of the plurality of fins, the plurality of pins and the fan makes that air enters the inlet of the cooling device in a first direction and exits the plurality of pins in a second direction which is substantially equal to the first direction, this direction being parallel to the fin lines 30. As a consequence, air follows a very straightforward path, with few pressure losses.

[0050] In this particular embodiment, these elements have been sized to cope with particular design conditions, and fins and pins have the following dimensions: [0051] the distance between two adjacent pins is approximately 4 mm; [0052] the distance between two adjacent fins is approximately 5 mm; and [0053] the distance between a fin and its closest pin is approximately 3 mm

[0054] Further, pins have a frustoconical shape, with a top diameter of approximately 2.5 mm. Further, fins have a base which is wider than the top portion, and this top portion is approximately 1.8 mm wide.

[0055] However, for different applications, these dimensions may be different.

[0056] FIG. 3 shows a perspective rear view of the cooling device 1 to show the external elements which form a closed duct for air to flow from the inlet 11 to the outlet 12.

[0057] Air flow is surrounded by a first and a second walls 71, 72, which also protrude from the heat sink 2 in the same direction as the fins and the pins. A close duct is completed by a plenum wall 73 which is parallel to the heat sink. The first and second walls 71, 72 are already shown in FIG. 2, but the plenum wall 73 was cut in that figure so that the different elements comprised in the interior of the cooling device may be seen.

[0058] FIG. 4 shows the automotive lighting device 10 shown in the previous figures mounted on an automotive vehicle 100. This lighting device 10, which provides a low beam functionality, may be equipped with powerful LEDs, the heat generated thereby being dissipated by the cooling device 1.