DK178968B1

DK178968B1 - Heat sink and lighting assembly comprising a heat sink

Info

Publication number: DK178968B1
Application number: DKPA201670114A
Authority: DK
Inventors: Alex Møller
Original assignee: Louis Poulsen As
Priority date: 2016-02-26
Filing date: 2016-02-26
Publication date: 2017-07-10
Also published as: DK201670114A1

Abstract

A heat sink for connecting to a heat dissipating source. The heat sink has a substrate with a bottom part for connecting to the heat dissipating source, and a plurality of substantially plate shaped heat dissipating fins with inner and outer surfaces and bottom, top and side edges. The heat dissipating fins are connected to the substrate and extend in an upwards direction from the substrate. The heat dissipating fins are arranged with a major part of the inner surface of each or at least part of the heat dissipating fins facing a centre part of the heat sink with air gaps or channels formed between the side edges or side edge parts of successively arranged heat dissipating fins. A light source can be connected to the bottom part of the heat sink substrate to provide a lighting assembly.

Description

TITLE

HEAT SINK AND LIGHTING ASSEMBLY COMPRISING A HEAT SINK TECHNICAL FIELD

The present disclosure relates to a heat sink and a lighting assembly comprising a heat sink and a light source.

BACKGROUND

Technology of heat dissipation plays an important role in the field of electronic apparatuses. With continuous development of consumer electronic apparatuses, the requirement and challenge of heat dissipation also increase. For example, tungsten lamps and halogen lamps have been replaced by light emitting diodes (LEDs). The main features of the LEDs are less power consumption, long service time, compact size and light weight. The LEDs also can emit various light so they can be extensively applied in many fields for indication and illumination. Although the LEDs generate less heat than conventional lighting devices, the problem of heat dissipation accompanied with high power LEDs still should be dealt with carefully. Furthermore, a driver unit for supplying electric power to the LEDs may be needed, and the arrangement of the driver unit should also be dealt with. U.S. Patent Application Publication No. 2012/0098429, U.S. Patent No. 8,348,471 and European Patent Publication No. 2 295 854 all disclose a heat sink structure for cooling LEDs and holding a driver unit. The disclosed heat sinks have a substrate and a plurality of heat dissipating fins extending outward from the substrate with air gaps or channels formed between the heat dissipating fins. The LEDs are mounted at the bottom of the substrate and a driver unit is mounted on top of the substrate and surrounded by the heat dissipating fins. The heat dissipating fins are almost triangular shaped with a wide bottom part and a narrow top part and extending outwards from the substrate at a high angle relative to the circumference of the substrate. The result is that the overall width of the heat sink is quite large compared to space left inside the heat dissipating fins for housing the driver unit.

It is desirable to provide a heat sink suitable for cooling heat dissipating devices, such as LED light sources, while having a compact size and maintaining a large space suitable for housing electronics, such as a driver unit for powering the LED light source. It is also desirable to provide a lighting assembly comprising a compact heat sink with an effective heat dissipation.

SUMMARY

It is an object of the invention to provide a heat sink, which has a compact size with a relatively large inner space, and which is shaped for an effective dissipation of heat.

It is also an object to provide a lighting assembly comprising a heat sink of compact size.

The foregoing and other objects are achieved by the features of the independent claim. Further implementation forms are apparent from the dependent claims, the description and the figures.

According to a first aspect there is provided a heat sink comprising: a substrate with a bottom part for connecting to a heat dissipating source, and a plurality of substantially plate shaped heat dissipating fins having inner and outer surfaces and bottom, top and side edges, wherein the heat dissipating fins are connected to the substrate and extend in an upwards direction from the bottom of the substrate, and wherein the heat dissipating fins are arranged with a major part of the inner surface of each or at least part of the heat dissipating fins facing a centre part of the heat sink with air gaps or channels formed between the side edges or side edge parts of successively arranged heat dissipating fins.

By having a major part of the inner surface of the heat dissipating fins facing the centre part of the heat sink, an inner heat sink space with air gaps or channels is defined by the substrate and the inner surfaces of the heat dissipating fins. The inner surface part of a heat dissipating fin or each of the heat dissipating fins facing the centre part of the heat sink may be at least 60%, such as at least 70%, such as at least 80%, or such as at least 90% of the inner surface part the heat dissipating fin.

It is within one or more embodiments of the first aspect that the heat dissipating source is a light source module or light source. The first aspect covers embodiments wherein the heat dissipating fins are connected to a circumference part of the substrate, and wherein the substrate may be arranged at a lower or bottom part of the heat dissipating fins. It is within an embodiment of the first aspect that the heat dissipating fins have an elongate shape with the air gaps/channels formed in a longitudinal direction of the heat dissipating fins. According to one or more embodiments of the first aspect, each or at least part of the heat dissipating fins have a curved shape in a direction substantial perpendicular to the direction of the air gaps/channels.

It is preferred that the first aspect covers one or more embodiments wherein for each heat dissipating fin a first bottom part of the heat dissipating fin is connected to the substrate and a second bottom part of the heat dissipating fin is not connected to the substrate, whereby an air gap is formed between the substrate and the second bottom part of the heat dissipating fin. The first aspect may also cover one or more embodiments, wherein a cover is connected to the heat dissipating fins at an upper part of the heat dissipating fins. Here, it is preferred that for each heat dissipating fin a first upper part of the heat dissipating fin is connected to the cover and a second upper part of the heat dissipating fin is not connected to the cover, whereby an air gap is formed between the cover and the second upper part of the heat dissipating fin.

According to one or more embodiments of the first aspect, the substrate may have a substantial downward conical shape with an upper part connecting to the heat dissipating fins, and a bottom part with a surface for connecting to a heat dissipating source, such as a light source module or light source. The bottom part of the substrate may have a thickness, which is larger than the thickness of the sidewalls of the upper part of the conical shaped substrate. The first aspect also covers embodiments wherein a receptacle is provided at the inner surface of at least two heat dissipating fins, where the receptacles may be formed for receiving a metal plate. The receptacles may extend in a direction from the bottom edge to the top edge of a heat dissipating fin, whereby a received plate can be hold in a direction extending from the bottom to the top of the heat dissipating fins.

According to a second aspect there is provided a lighting assembly comprising: a heat sink having a substrate and a number of heat dissipating fins connected to an upper part of the substrate, and a light source module with at least one light source, wherein the light source module is connected to the heat sink substrate opposite to the heat dissipating fins. The heat sink of the second aspect may be selected from any of the embodiments of a heat sink of the first aspect of the invention and the light source module may be connected to a bottom part or bottom surface part of the heat sink substrate. It is preferred that the light source module comprises one or more light emitting diodes, such as a chip on board light emitting diode, COB LED, module.

The lighting assembly of the second aspect may comprise a driver for supplying power to the light source module, where the driver may be arranged between the heat dissipating fins, above the substrate and opposite the light source module. The driver may connected to a metal plate received by two receptacles provided at the inner surface of two heat dissipating fins.

It is within one or more embodiments of the lighting assembly of the second aspect that a number of lampshade holders are secured to the substrate below the heat dissipating fins and above the light source module. It is also within embodiments of the second aspect that a cover is connected to the heat dissipating fins at an upper part of the heat dissipating fins, and that a number of lampshade holders are secured to the cover. The lampshade holders of the substrate may define a first outer circumference and the lampshade holders of the cover may define a second outer circumference, which is smaller than the first outer circumference. The second aspect also covers embodiments wherein a number of inner curved lampshade parts are connected to the lampshade holders of the cover and to an inner part of the lampshade holders of the substrate, and wherein a number of outer curved lampshade parts are connected to an outer part of the lampshade holders of the substrate.

These and other aspects of the invention will be apparent from and the embodiment(s) described below.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following detailed portion of the present disclosure, the invention will be explained in more detail with reference to the example embodiments shown in the drawings, in which:

Fig. 1 is a perspective view of a heat sink according to an exemplary embodiment;

Fig. 2 is a perspective view of a substrate and a single heat dissipating fin making up part of a heat sink according to an exemplary embodiment;

Fig. 3 is a top down view of a heat sink without any cover at the top according to an exemplary embodiment;

Fig. 4 is a top down view of the heat sink of Fig. 3 with a driver plate arranged at an inner space according to an exemplary embodiment;

Fig. 5 illustrates an arrangement of a driver unit within the inner space of a heat sink according to an exemplary embodiment;

Fig. 6 is a bottom view of a lighting assembly according to an exemplary embodiment;

Fig. 7 is a bottom view of a lighting assembly with a reflector according to an exemplary embodiment; and

Fig. 8 is a perspective view of a lighting assembly with lampshades according to an exemplary embodiment.

DETAILED DESCRIPTION

Fig. 1 shows a heat sink 100 according to an example embodiment. The heat sink 100 includes a substrate 101, three substantially plate shaped heat dissipating fins 102a, b, c, and a cover 103. The substrate 101 has a bottom surface 107 for connecting to a heat dissipating source, such as a light source module or light source. Each heat dissipating fin 102a,b,c has inner and outer surfaces and bottom, top and side edges. The heat dissipating fins 102 a,b,c are connected to a circumference part of the substrate 101 so as to extend in an upward direction from the bottom of the substrate 101 and with a major part of the inner surface of the heat dissipating fins 102a,b,c facing a centre part of the heat sink 100. Three side air gaps or channels 104a,b,c (of which the air channels 104b and 104c are not shown in Fig. 1) are formed between the side edges of each of two successively arranged heat dissipating fins 102a, 102b, and 102b, 102c, and 102c, 102a.

The cover 103 show in the embodiment of Fig. 1 also holds three lampshade holders 123a,b,c. However, the invention also covers embodiments without the lampshade holders 123a,b,c. Although not being part of the heat sink 100 itself, a power cable 118 is shown in Fig. 1, which cable 118 may provide power to a driver for a heat dissipating source being connected to the heat sink 100. Also a wire 127 for holding the heatsink 100 is shown in Fig. 1.

For each heat dissipating fin 102a,b,c a first bottom part is connected to an upper part of the substrate 101 while the opposite second bottom part is left free, and a first upper or top part is connected to the cover 103 while the opposite second upper or top part is left free. By this connection of the heat dissipating fins 102a,b,c to the substrate 101 and the cover 103, a first side edge part of each heat dissipating fin 102a,b,c connects the substrate 101 and the cover 103, while the opposite second side edge part is left free, thereby forming the side air gaps or channels 104a,b,c between the side edges of the heat dissipating fins 102a,b,c.

Furthermore, this connection of the heat dissipating fins 102a,b,c to the substrate 101 and the cover 103 gives room to a bottom air gap 105a,b,c (of which air gaps 105b,c are not shown in Fig. 1) between the substrate 101 and the non-connected second bottom part of each heat dissipating fin 102a,b,c, and further to a top air gap 106a,b,c (of which air gap 106c is not shown in Fig. 1) between the cover 103 and the non-connected second upper part of each heat dissipating fin 102a,b,c.

For the heat sink 100, an inner heat sink space is defined by the substrate 101, the cover 103, and the inner surfaces of the heat dissipating fins 102a,b,c, see also Fig. 3. In order to obtain a large inner space of the heat sink 100, while keeping the outer dimensions at a minimum, the heat dissipating fins 102a, b, care arranged with no or only a minor overlap between the heat dissipating fins 102a,b,c, whereby almost all the inner surface of each heat dissipating fin faces the centre of the heat sink. It is preferred that at least 70%, such as at least 80%, or such as at least 90% of the inner surface area of the heat dissipating fins 102a,b,c is facing the centre of the heat sink 100. The present invention also covers embodiments in which there is an overlap between the heat dissipating fins 102a,b,c, and where at least 60% of the inner surface area of the heat dissipating fins 102a,b,c may be facing the centre of the heat sink 100.

When a heat dissipating source is connected to the bottom part 107 of the substrate 101, the temperature of the inner space can be hold at a relatively low temperature due to the heat being conducted away by the heat dissipating fins 102a,b,c and the air cooling effected by the side air gaps or channels 104a,b,c, the bottom air gaps 105a,b,c, and the top 106a,b,c air gaps. The inner space provided by the heat sink 100 is therefore well suited for housing electronic circuitry such as a driver for supplying power to a heat dissipating source connected to the substrate 101.

The substrate 101 of the heat sink 100 has a substantial downward conical shape, where an upper part is connected to the heat dissipating fins 102a,b,c, and where the bottom part 107 has a surface, which can be connected to a heat dissipating source, such as a light source module or light source. The present invention also covers embodiments in which the substrate 101 has other shapes than conical, and the substrate 101 may have a bottom surface area defined by the outer circumference of the substrate 101.

The heat sink 100 shown in Fig. 1 holds three heat dissipating fins 102a,b,c, but it is within exemplary embodiments that the heat sink 100 may hold another number of heat dissipating fins such as two, four, five, six, seven, eight, nine or ten heat dissipating fins.

The substrate 101 and cover 103 shown in Fig. 1 each has a substantially circular outer circumference, and the heat dissipating fins 102,a,b,c have an elongate and curved shape. The curvature of the heat dissipating fins 102a,b,c may be larger or slightly larger than the curvature of the outer circumference of the substrate 101. The air gaps or channels 104a,b,c extend in the longitudinal direction of the heat dissipating fins 102a,b,c, and the curvature of the heat dissipating fins 102a,b,c is in a direction substantial perpendicular to the direction of the air gaps or channels 104a,b,c.

It is also within exemplary embodiments that the heat dissipating fins 102a,b,c has the same curvature as the outer circumference of the substrate 101, or that the heat dissipating fins 102a,b,c are flat without any curvature. The invention also covers heat sinks 100 for which the substrate 101 and/or the cover 103 have other shapes than circular, such as for example elliptical or the shape of a polygon, including the shape of a square, rectangle, trapezoid, pentagon, hexagon, heptagon and an octagon.

Fig. 2 is a perspective view of a substrate 201 and a single heat dissipating fin 202, which can be used for making up part of the heat sink 100. The substrate 201 has an upper circumferential part with notches 209 for receiving a first bottom part of the heat dissipating fins 202. The heat dissipating fin 202 holds a receptacle 210 at the inner surface, and each notch 209 in the substrate 201 is formed for receiving a lower part of the receptacle 210 and a lower or bottom first side edge part of the heat dissipating fin 202. The heat dissipating fin 202 is curved with a larger curvature than the circumference of the substrate 201, and the notch 209 is formed in order to hold the lower or bottom second side edge part of the heat dissipating fin 202 free of the substrate 201, thereby creating a bottom air gap 205. The receptacle 210 is a female receptacle having one or more receiving grooves 211 extending from the bottom to the top of the heat dissipating fin 202. The substrate 201 is provided with one or two through-going holes or bores 212, which can be used for guiding electrical conductors from the top to the bottom of the substrate 201.

Fig. 3 is a top down view of a heat sink 300 without any cover at the top according to an exemplary embodiment. The heat sink 300 has a substrate 301 similar to the substrate 201 of Fig. 2, with three heat dissipating fins 302a,b,c, connected to the substrate 301. An inner heat sink space 315 is defined by the substrate 301 and the heat dissipating fins 302a,b,c. The heat dissipating fins 302a,b,c are similar to the heat dissipating fin 202 of Fig. 2. Fig. 3 illustrates how three side air gaps or channels 304a,b,c are formed between the side edges of two successively arranged heat dissipating fins 302a,b,c. Each heat dissipating fin 302a,b,c has a receptacle 310 extending from the bottom to the top of the heat dissipating fin 302a,b,c and each receptacle has a receiving middle groove 311, and two different angled first and second oouter receiving grooves 313 and 314.

Fig. 4 is a top down view of the heat sink 300 of Fig. 3 with a driver plate 316 arranged at the inner space 315 according to an exemplary embodiment. The driver plate 316 is received by outer groove 313a of the first heat dissipating fin 302a and by outer groove 314c of the third heat dissipating fin 302c.

Fig. 5 illustrates an arrangement of an electrical driver unit 317 within the inner space 315 of the heat sink 300 of Fig. 3 and 4. In Fig. 5 the second heat dissipating fin 302b is removed and also there is no cover on top of the heat sink 300. The driver unit 317 is secured to the driver plate 316 and receives electrical power by a power cable 318. Conductors 319a with connectors 319b are provided as outputs from the driver unit 317, and power can be delivered from the driver unit 317 to a heat dissipating source, such as a light source, at the bottom of the substrate 301 by inserting conductors from the connectors 319b to the bottom of the substrate via one or two through-going bores 312. The substrate 301 has a downward conical shape with an internal recess leaving some free space between the bottom part of the substrate 301, to which the heat dissipating source being powered by the driver unit 317 may be connected, and the driver unit 317. When a heat dissipating source is connected to the bottom of the substrate 301, dissipated heat will be conducted through the bottom part and the walls of the substrate and transferred to the heat dissipating fins 302a,b,c, which are cooled by air flowing on both sides of the fins 302a,b,c. A wire 327 for holding the heat sink 300 is also shown in Fig. 5.

Fig. 6 is a bottom view of a lighting assembly 600 according to an exemplary embodiment. The assembly 600 holds a heat sink, which may be similar to the heat sink 300 of Fig. 5 having a driver unit 317 arranged at the inner space 315. The heat sink of the assembly 600 has a cover 603 on top of heat dissipating fins 602 connected to a substrate 601 with a bottom surface 607 connected to a light source 624. The light source 624 is thermally connected to the bottom surface 607 of the substrate 601, whereby heat is transferred from the light source 624 to the substrate 601 and further to the heat dissipating fins 602. A light diffuser or reflector 621 is secured to the substrate 601 between the bottom surface 607 and the heat dissipating fins 602. A number of lampshades may be attached to the assembly 600, and a number of lampshade holders 622 is secured to the substrate 601 and a number of lampshade holders 623 is secured to the cover 603. The light source 624 may be a light emitting diode, LED, light source, such a chip on board, COB, LED light source. The invention further covers embodiments of a lighting assembly similar to the assembly 600, but without the diffuser or reflector 621, and also covers embodiments without the lampshade holders 622 and 623.

The assembly 600 may be provided with six lampshade holders 622 connected to the substrate 601 and three lampshade holders 623 connected to the cover 603. The lampshade holders 622 may define a first outer circumference, which is larger than a second outer circumference defined by the lampshade holders 623.

Fig. 7 is a perspective view of a lighting assembly 700 according to an exemplary embodiment. The lighting assembly 700 is similar to the lighting assembly 600 of Fig. 6, but further holds a light reflector 625 and a bottom diffuser 626. The reflector 625 is secured to the substrate 601 between the light diffuser 621 and the light source 624, and the bottom diffuser 626 is connected to the reflector 625 below the light source 624.

Fig. 8 is a perspective view of a light assembly 800 according to an exemplary embodiment. The assembly 800 is composed of the light assembly 700 of Fig. 7, which is further provided with lampshade parts 828a,b,c and 829a,b,c. Three outer curved lampshade parts 828a,b,c are connected to the outer circumference of the lampshade holders 622 of the substrate 601, and three curved inner lampshade parts 829a,b,c are connected to the lampshade holders 623 of the cover 603 and an inner part of the lampshade holders 622 of the substrate 601. The lampshade parts 828a,b,c and 829a,b,c extend in an upward direction from the bottom of the assembly 800, whereby air can flow inside the lampshade parts 828a,b,c and 829a,b,c from the bottom to the top of the assembly 800. The outer lampshade parts 828a,b,c are arranged at the lampshade holders 622 so that outer air gaps or channels are formed between the side edges of each of two successively arranged outer lampshade parts 828a,b,c, and the inner lampshade parts 829a,b,c are arranged at the lampshade holders 623 so that inner air gaps or channels are formed between the side edges of each of two successively arranged inner lampshade parts 829a,b,c. These inner and outer air gaps or channels further help the air to flow inside the lampshade parts 828a,b,c and 829a,b,c and thereby to provide an air flow for the heat sink surrounded by the inner lampshade parts 829a,b,c. A wire 827 for holding the assembly 800 is also shown in Fig. 8.

It is within one or more embodiments of the invention that the heat dissipating fins 102, 202, 302, 602, the substrate 101, 201, 301, 601, and the top cover 103, 603 are made in aluminium. According to an example embodiment, the heat dissipating fins 102, 202, 302, 602 have a plate thickness in the range of 2-4 mm, such as about 3 mm, a height in the range of 250-350 mm, such as about 300 mm, a width in the range of 100-130 mm, such as about 115 mm, and a curvature with an inner radius in the range of 60-80 mm. It is also within the example embodiment that the substrate 101, 201, 301, 601 and the top cover 103, 603 have an outer diameter in the range of 110-130 mm, such as about 119 mm or 120 mm, where the top cover may have a slightly larger outer diameter, such as 120 mm, compared to the outer diameter of the substrate, which may be 119 mm. The top cover 103, 601 may have an outer wall with a wall height in the range of 10-20 mm, such as about 20 mm, and the conical shaped substrate 101, 201, 301, 601 may have a bottom part with a thickness in the range of 25-35 mm, such as about 30 mm, which is larger than the thickness of the sidewalls of the upper part of the substrate 101, 201, 301, 601, where the wall thickness of the sidewalls may be in the range of 10- 25 mm, such as about 15 mm. By having a substrate 101,201, 301, 601 with a rather thick bottom part, to which the light source 624 is thermally connected, the heat dissipated from the light source 624 is effectively absorbed by the substrate 101, 201, 301, 601 in order to be conducted to the heat dissipating fins 102, 202, 302, 602. In order to obtain an effective air flow within the heat sink 100, 300, it is preferred that the width or opening of the air gaps or channels 104, 304, 105 and 106 is not smaller than 4 mm, while for safety reasons it is preferred that the width or opening of the air gaps or channels 104, 304, 105 and 106 is not larger than 12 mm.

According to an example embodiment of the lighting assembly 800, the light source 624 is a COB LED light source, such as a Citizen CLU046 COB LED, which is powered by a driver unit 317 delivering a constant current about 900 mA, whereby a luminous flux about 3300 Im is obtained with a total power consumption about 35 W. The light diffuser 621 is made of a plastic material with an outer diameter in the range of 220-260 mm, such as 240 mm or 241 mm. The light reflector 625 is made of aluminium with a lower, outer diameter in the range of 300-340 mm, such as 318 mm or 320 mm, and the bottom diffuser 626 is also made of a plastic material and has an outer diameter, which is smaller than the diameter of the light diffuser 621, and which is equal to or larger than the outer diameter of the substrate 601. The lampshade holders 622 and 623 and the lampshade parts 824 and 825 are all made in aluminium, and the inner lampshade parts 829 are arranged with a maximum outer diameter in the range of 215-240 mm, such a 225 mm or 226 mm, and the outer lampshade parts 828 are arranged with a maximum outer diameter in the range of 340-380 mm, such a 360 mm or 366 mm.

The invention has been described in conjunction with various embodiments herein. However, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality.

Claims

A heat dissipator (100, 300) comprising: a base (101, 201, 301, 601) having a bottom portion (107, 607) for connection to a heat emitting source (624); and a plurality of heat-emitting ribs (102a, b, c, 202, 302a, b, c, 602); wherein the heat emitting ribs (102a, b, c, 202, 302a, b, c, 602) are connected to the base (101, 201, 301, 601), extending in an upward direction from the base; and where air gaps or ducts (104a, 304a, b, c) are formed between side edges or side edge portions of successively arranged heat emitting ribs (102a, b, c, 202, 302a, b, c, 602); characterized in that the heat-emitting ribs (102a, b, c, 202, 302a, b, c, 602) are mainly plate-shaped ribs having inner and outer surfaces and bottom, top and side edges, and in that the heat-emitting ribs ( 102a, b, c, 202, 302a, b, c, 602) are arranged with the majority of the inner surface of each or at least a portion of the heat emitting fins facing a center portion of the heat sink.

A heat dissipator (100, 300) according to claim 1, wherein the heat emitting ribs (102a, b, c, 202, 302a, b, c, 602) are connected to a circumferential portion of the base (101, 201, 301, 601), and wherein the heat-releasing ribs (102a, b, c, 202, 302a, b, c, 602) have an elongated air gap / duct form (104a, 304a, b, c) formed in a longitudinal direction of the heat-releasing ribs.

A heat dissipator (100, 300) according to claim 1 or 2, wherein each or at least a portion of the heat emitting ribs (102a, b, c, 202, 302a, b, c, 602) has a curved shape in a direction generally perpendicular on the direction of the air gaps / ducts (104a, 304a, b, c).

A heat dissipator (100, 300) according to any one of claims 1 to 3, wherein the base (101, 201, 301, 601) is arranged at a lower part or a bottom part of the heat emitting ribs (102a, b, c). 202, 302a, b, c, 602).

A heat dissipator (100, 300) according to any one of claims 1 to 4, wherein, for each heat emitting rib (102a, b, c, 202, 302a, b, c, 602), a first bottom portion of the heat emitting rib is connected to the base (101,201, 301, 601), and another bottom portion of the heat emitting rib is not connected to the base, and an air gap (105a, 205) is formed between the base (101, 201, 301, 601) and the other bottom portion of the heat-releasing rib.

A heat dissipator (100, 300) according to any one of claims 1 to 5, wherein a cover (103, 603) is connected to the heat emitting ribs (102a, b, c, 602) at an upper part of the heat emitting ribs. and wherein, for each heat-releasing rib, a first upper portion of the heat-releasing rib is connected to the cover (103, 603) and a second upper portion of the heat-releasing rib is not connected to the cover, an air gap (106a, b) is formed between the cover (103) and the second upper portion of the heat-releasing rib (102a, b).

A heat dissipator (100, 300) according to any one of claims 1 to 6, wherein the base (101, 201, 301, 601) has a substantially downwardly tapered shape with an upper portion connected to the heat emitting ribs (102a, b, (c, 202, 302a, b, c, 602) and a bottom portion having a surface (107, 607) for connection to a heat emitting source (624).

A heat dissipator (100, 300) according to any one of claims 1 to 7, wherein a receiving structure (210, 310) is provided at the inner surface of at least two heat-dissipating ribs (202, 302a, b, c), which receiving structures (210, 310) is configured to receive a metal plate (316).

Lighting device (600) comprising: a heat sink (100, 300) according to any one of claims 1 to 8; and a light source module (624) having at least one light source; wherein the light source module (624) is connected to the bottom portion (107, 607) of the base (101, 301, 601) of the heat dissipator opposite to the heat emitting ribs (102a, b, c, 302a, b, c, 602).

Lighting device (600) according to claim 9, further comprising a drive unit (317) for supplying power to the light source module (624), wherein the drive unit (317) is disposed between the heat emitting ribs (302a, 302c, 602), above the base 301,601. ) and opposite the light source module (624).

Illumination device (600) according to claim 10, wherein the drive unit (317) is connected to a metal plate (316) received by two receiving structures (310) provided at the inner surface of two heat emitting ribs (302a, c). .

Lighting device (600) according to any one of claims 9 to 11, wherein the light source module (624) comprises one or more light emitting diodes.

Illumination device (600) according to any one of claims 9 to 12, wherein a plurality of lampshade holders (622) are attached to the base (601) below the heat emitting ribs (602) and above the light source module (624).

Lighting device (600) according to any one of claims 9 to 13, wherein a cover (603) is connected to the heat emitting ribs (602) at an upper part of the heat emitting ribs (602) with a plurality of lampshade holders (623). attached to the cover (603), wherein the base lampshade holders (622) define a first outer circumference, and the cover lampshade holders (623) define a second outer circumference less than the first outer circumference.

The lighting device (600) of claim 14, wherein a plurality of inner curved lampshade portions (829a, b, c) are connected to the lampshade holders (623) of the cover and to an inner portion of the base lampshade holders (622), and wherein a plurality of exteriors, curved lampshade portions (828a, b, c) are connected to an outer portion of the base lampshade holders (622).