LED lighting device

Abstract

The invention provides a lighting device (100) comprising a vapor chamber unit (200), a heat sink (300), and a plurality of light sources (10), wherein: the vapor chamber unit (200) comprises a vapor chamber (210) defined by at least a first plate (211) and a second plate (212) having an average plate distance (d1), wherein the vapor chamber (210) comprises a first A chamber end (221) and a second chamber end (222) defining a chamber length (L1), wherein the vapor chamber unit (200) comprises (i) a first external face (231) defined by at least part of the first plate (211), wherein the first external face (231) is convex, and (ii) a second external face (232) defined by at least part of the second plate (212); the heat sink (300) is thermally coupled to the vapor chamber unit (200); and the light sources (10) are configured to generate light source light.

Claims

1. A lighting device comprising a vapor chamber unit, a heat sink, and a plurality of light sources, wherein: the vapor chamber unit comprises a vapor chamber defined by at least a first plate and a second plate having an average plate distance (d1) between the first plate and the second plate, wherein the vapor chamber comprises a first chamber end and a second chamber end defining a chamber length (L1), wherein the vapor chamber unit comprises (i) a first external face defined by at least part of the first plate, wherein the first external face is convex, and (ii) a second external face defined by at least part of the second plate; the heat sink is thermally coupled to the vapor chamber unit; and the light sources are configured to generate light source light, and wherein the light sources are associated with the first external face, wherein the first external face has a cross-sectional shape selected from triangular, square, pentagonal, hexagonal, heptagonal, octagonal, polygonal having more than 8 faces, oval, and round, and wherein the second external face defines a cavity circumferentially and completely enclosed by the vapor chamber.

2. The lighting device according to claim 1, wherein the vapor chamber unit has a cross-sectional shape that is cylindrical.

3. The lighting device according to claim 1, wherein the average plate distance (d1) is selected from the range of 50 μm-5 mm, wherein the first plate and the second plate comprise a material selected from the group consisting of aluminum, copper, and steel, wherein the first plate and a second plate each have a second thickness independently selected from the range of 50-5000 μm, wherein the chamber length (L1) and the average plate distance (d1) have a ratio selected from the range of L1/d1≥10, and wherein the plurality of light sources comprises solid state light sources.

4. The lighting device (according to claim 1, wherein all light sources are configured at a second distance from the second end independently selected from the range of at least 0.2*L1.

5. The lighting device according to claim 1, wherein the heat sink is configured closer to the second chamber end than to the first chamber end.

6. The lighting device according to claim 1, wherein the heat sink comprises a plurality of heat sink fins.

7. The lighting device according to claim 6, wherein one or more of the heat sink fins are configured in the cavity.

8. The lighting device according to claim 6, wherein the vapor chamber unit and the heat sink fins are a monolithic body.

9. The lighting device according to claim 1, further comprising a cooling element, configured to cool the vapor chamber unit.

10. The lighting device according to claim 9, wherein the cooling element is configured to generate a gas flow along the second external face.

11. The lighting device according to claim 1, further comprising electronics, wherein at least part of the electronics is configured in the cavity according to claim 1.

12. The lighting device according to claim 1, wherein the light sources are associated to a flexible PCB which is associated to the first external face.

13. The lighting device according to claim 12, wherein the flexible PCB comprises a metal carrier, wherein the metal carrier is soldered to the first external face.

14. A module comprising a reflector and the lighting device according to claim 1, wherein reflector partly circumferentially surrounds the lighting device, and wherein the reflector is configured to redirect at least part of the light source light.

15. A street lighting luminaire comprising the module according to claim 14, wherein the street lighting luminaire comprises a pole.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

(2) FIGS. 1a-1d schematically depict some embodiments and variants of the lighting device;

(3) FIGS. 2a-2b schematically depict some further embodiments and variants; and

(4) FIG. 3 schematically depict some further aspects.

(5) The schematic drawings are not necessarily to scale.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(6) FIGS. 1a-1b schematically depict an embodiment of a lighting device 100 comprising a vapor chamber unit 200 and one or more light sources 10. Here, a plurality of light sources 10 is schematically depicted. The plurality of light sources 10 comprises solid state light sources.

(7) Further, the lighting device 100 may optionally comprise a heat sink 300 (which is also depicted in FIG. 1a). Here, schematically the heat sink 300 is depicted at (or close to) one of the ends of the vapor chamber unit.

(8) The vapor chamber unit 200 comprises a vapor chamber 210. This vapor chamber 210 is especially defined by at least a first plate 211 and a second plate 212. These plates 211,212 have an average plate distance d1. In embodiments, the average plate distance d1 may be selected from the range of 50 μm-5 mm. The first plate 211 and a second plate 212 may each have a second thickness d2 independently selected from the range of 50-5000 μm, such as 300-2000 μm. The first plate 211 and a second plate 212 comprise a material selected from the group consisting of aluminum, copper, and (stainless) steel. The vapor chamber 210 may comprise wick material (not depicted).

(9) The vapor chamber 210 comprises a first chamber end 221 and a second chamber end 222 defining a chamber length L1. The chamber length L1 and the average plate distance d1 may e.g. have a ratio selected from the range of L1/d1≥10. Note that the optional heat sink 300 is configured closer to the second end than to the first end, and the light sources are configured closer to the first end than to the second end in this schematically depicted embodiment. However, other variants may also be possible.

(10) Further, the vapor chamber unit 200 comprises a first external face 231 defined by at least part of the first plate 211. The vapor chamber unit 200 also comprises a second external face 232 defined by at least part of the second plate 212. Here, in this schematically depicted embodiment the first external face 231 is convex.

(11) As schematically depicted, the heat sink 300 is thermally coupled to the vapor chamber unit 200.

(12) The light sources 10 are configured to generate light source light 11. The light sources 10 are associated with the first external face 231. The lighting device 100 is configured to generate lighting device light 101, which may essentially consist of the light source light 11 (of the light source(s) 10). For instance, the light sources may be available on a PCB or may be available in the form of LED strip (PCB or strip not depicted); though other options may also be possible.

(13) The first external face 231 may have a cross-sectional shape selected from triangular, square, pentagonal, hexagonal (see FIG. 1c), heptagonal, octagonal, oval, and round (see FIG. 1b). Here, the cross-sectional shape is e.g. round (see FIG. 1b). The cross-sectional shape is especially the cross-section perpendicular to an axis of elongation A. Further, the second external face 232 here defines a cavity 240 circumferentially enclosed by the vapor chamber 210. This cavity 240 may optionally be used in several ways, see further below.

(14) Hence, the embodiment schematically depicted in FIGS. 1a-1b is of a vapor chamber unit 200 having a cross-sectional shape that is cylindrical. However, other shapes are also possible (see FIG. 1c).

(15) In FIG. 1a, an embodiment is schematically depicted wherein all light sources 10 are configured at a second distance L2 from the second end 222 independently selected from the range of at least 0.2*L1.

(16) In FIG. 1a, also an embodiment is schematically depicted wherein the heat sink 300 is configured closer to the second chamber end 222 than to the first chamber end 221.

(17) Further, the (optional) heat sink 300 may comprise a plurality of heat sink fins 310.

(18) In FIG. 1a, the cavity 240 seems to be closed (essentially due to a closed second external surface 232). This is however not necessarily the case, see e.g. also FIGS. 1d and 2a.

(19) FIG. 1c schematically depicts an embodiment wherein the cross-sectional shape of the first external face is not round, but hexagonal shaped. Further, though not limited to this specific hexagonal shaped embodiment, FIG. 1c schematically depicts an embodiment wherein one or more of the heat sink fins 310 are configured in the cavity 240.

(20) In above embodiments, a variant may be wherein the vapor chamber unit 200 and the heat sink fins 310 are a monolithic body.

(21) FIG. 1d schematically depicts an embodiment of the lighting device 100 wherein the first external face 231 has a cross-sectional shape which is not closed. The second external face 232 defines a cavity 240 partly circumferentially enclosed by the vapor chamber 210. FIG. 1d schematically depicts an embodiment of e.g. a hexagonal cross-section (of the first external face 231, or the second external face 232, or the vapor chamber 210) without 1-3 of the six sides.

(22) FIG. 2a schematically depicts an embodiment of the lighting device 100, further comprising a cooling element 400. The cooling element 400 is especially configured to cool the vapor chamber unit 200. Schematically, an embodiment is depicted wherein the cooling element 400 is configured to generate a gas flow along the second external face 232, such as a fan. Also here, by way of example a variant is depicted wherein optionally the vapor chamber unit 200 and the heat sink fins 310 are a monolithic body. Note that of course also heat sink fins 310 may be available at the first external face 231, as embodiments may be combined (see also below).

(23) Reference 500 refers to electronics, e.g. to drive the light source(s) 10. Further, by way of example an Edison type screw is depicted.

(24) Like in the other Figures, FIG. 2b schematically depicts a number of embodiments and variants in a single Figure. This does not necessarily imply that all elements depicted are necessarily available in a single embodiment. Elements may also be combined with other embodiments herein schematically depicted or herein described.

(25) FIG. 2b schematically depicts an embodiment further comprising electronics 500, wherein at least part of the electronics 500 is configured in the cavity 240. Further, by way of example a further vapor chamber 610 is available. Reference 610a shows such further vapor chamber, which may be used to guide away thermal energy of the electronics 500 and/or of the light sources 10.

(26) FIG. 2b also schematically depicts an embodiment of the heat sink 300, comprising a cavity wherein the vapor chamber unit 200 is partly configured. Further, by way of example one or more of the heat sink fins 310 may alternatively or additionally comprise a further vapor chamber 610. This alternative or additional further vapor chamber 610 is indicated with reference 610b.

(27) The heat sink 300 may comprise a massive body, which may alternatively or additionally comprise a further vapor chamber 610 (not comprised by the heat fins 310), indicated with reference 610c.

(28) Here, the further vapor chambers 610 are not in communication with the vapor chamber 210. However, in alternative embodiments a further vapor chamber 610 may also in gaseous communication with the vapor chamber 210.

(29) FIG. 3 schematically depicts an embodiment of a module 1000 comprising a reflector 1100 and the lighting device 100. The reflector 1100 partly circumferentially surrounds the lighting device 100. Especially, the reflector 1100 is configured to redirect at least part of the light source light 11. FIG. 3 also schematically depicts a street lighting luminaire 2000 comprising the module 1000. Here, by way of example the street lighting luminaire 2000 comprises a pole.

(30) Simulations were executed with the vapor chamber. It was in this way experimentally showed that the light sources may be operated at a lower temperature as more heat is dissipated. This may prolong the lifetime of the light sources. Further, the weight of the lighting device may be lower due to the vapor chamber(s) which reduce weight, relative to variants without such vapor chamber.

(31) The term “plurality” refers to two or more.

(32) The terms “substantially” or “essentially” herein, and similar terms, will be understood by the person skilled in the art. The terms “substantially” or “essentially” may also include embodiments with “entirely”, “completely”, “all”, etc. Hence, in embodiments the adjective substantially or essentially may also be removed. Where applicable, the term “substantially” or the term “essentially” may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%.

(33) The term “comprise” includes also embodiments wherein the term “comprises” means “consists of”.

(34) The term “and/or” especially relates to one or more of the items mentioned before and after “and/or”. For instance, a phrase “item 1 and/or item 2” and similar phrases may relate to one or more of item 1 and item 2. The term “comprising” may in an embodiment refer to “consisting of” but may in another embodiment also refer to “containing at least the defined species and optionally one or more other species”.

(35) Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

(36) The devices, apparatus, or systems may herein amongst others be described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation, or devices, apparatus, or systems in operation.

(37) It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims.

(38) In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

(39) Use of the verb “to comprise” and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”.

(40) The article “a” or “an” preceding an element does not exclude the presence of a plurality of such elements.

(41) The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a device claim, or an apparatus claim, or a system claim, enumerating several means, several of these means may be embodied by one and the same item of hardware. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

(42) The invention also provides a control system that may control the device, apparatus, or system, or that may execute the herein described method or process. Yet further, the invention also provides a computer program product, when running on a computer which is functionally coupled to or comprised by the device, apparatus, or system, controls one or more controllable elements of such device, apparatus, or system.

(43) The invention further applies to a device, apparatus, or system comprising one or more of the characterizing features described in the description and/or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterizing features described in the description and/or shown in the attached drawings.

(44) The various aspects discussed in this patent can be combined in order to provide additional advantages. Further, the person skilled in the art will understand that embodiments can be combined, and that also more than two embodiments can be combined. Furthermore, some of the features can form the basis for one or more divisional applications.