WO2013153116A1

WO2013153116A1 - Illuminating device, omnidirectional luminaire and retrofit lamp with the illuminating device

Info

Publication number: WO2013153116A1
Application number: PCT/EP2013/057495
Authority: WO
Inventors: Hongwei Zhang; Jing Lin; Hui GUI; Xiaoyu Chen; Jin Hu
Original assignee: Osram Gmbh
Priority date: 2012-04-13
Filing date: 2013-04-10
Publication date: 2013-10-17
Also published as: CN103375693A

Abstract

The present invention relates to an illuminating device (100), comprising a plurality of light sources (1), a bulb (2) and a heat sink (3), characterized by that the heat sink (3) comprises a base (4) and a plurality of support arms (5) extending from a circumferential edge of the base (4), an inner surface of respective support arm (5) is mounted with a part of the light source (1), and the heat sink (3) is partially inserted into the bulb (2) with the plurality of support arms (5) and define an enclosed space (R) with the bulb (2) for accommodating the light sources (1). In addition, the present invention further relates to an omnidirectional luminaire and a retrofit lamp comprising such heat sink.

Description

Illuminating Device, Omnidirectional Luminaire and Retrofit Lamp with the Illuminating Device

Technical Field

The present invention relates to an illuminating device, an omnidirectional luminaire and a retrofit lamp with the illu^¬ minating device. Background Art

With the development of illumination technology, the omnidi^¬ rectional illuminating devices have gradually become a new research field. The omnidirectional illuminating devices gen^¬ erally refer to illuminating devices having a uniform light distribution over a large area. The light diffusion angle

(light distribution angle) of an omnidirectional illuminating device in the prior art has reached 320°. Especially in the US market, many illuminating devices must be designed as en^¬ ergy-saving illuminating devices in order to meet the "Energy Star" criteria. The research and development goal at the cur^¬ rent stage is to enable the omnidirectional illuminating de^¬ vice to completely meet the "Energy Star" criteria, while having a low BOM and low manufacturing cost.

The currently known omnidirectional illuminating devices are, for example: with a complicated heat dissipation structure, and with many LEDs placed all around the surface of the illu^¬ minating device; with LED arrays arranged in a form of fly- eye; with remote phosphor light bulbs; with light guide structures; or with reflecting structures inside the bulb. Although the omnidirectional illuminating devices of the above types substantially can achieve the expected illumina^¬ tion effects, they have either a very high manufacturing cost or material cost. For the omnidirectional illuminating de^¬ vices, another problem to be solved is how to enhance the brightness of the omnidirectional illuminating devices, and to reasonably use a heat sink to release the heat in the il^¬ lumination device generated by, for example, the light source .

Summary of the Invention Therefore, one object of the present invention lies in pro^¬ viding an illuminating device that is featured by a low cost, a simple structure and easy installation, and can realize good heat dissipating and illuminating effects. The illuminating device in accordance with the present inven^¬ tion comprises a plurality of light sources, a bulb and a heat sink, characterized by that the heat sink comprises a base and a plurality of support arms extending from a circum^¬ ferential edge of the base, an inner surface of respective support arm is mounted with a part of the light source, and the heat sink is partially inserted into the bulb with the plurality of support arms and define an enclosed space with the bulb for accommodating the light sources. Assembling the bulb and the heat sink together can define the enclosed space for mixing light so that light can directly emerge outwardly from inside of the bulb and the luminous efficiency is im^¬ proved. Illumination to different directions is provided and the illuminating range of emergent light is increased by us^¬ ing a plurality of support arms; moreover, compared with the prior "basin-shaped" heat sink, the heat sink in accordance with the present invention has a reduced mass, a low cost and advantageously supports the bulb. Besides, as the light sources that generate heat in operation are mounted on the support arms, the heat can be transferred directly in a ther^¬ mal contact manner to the whole heat sink, and thus heat dis^¬ sipation is realized. The heat sink in accordance with the present invention has dual functions of providing support and dissipating heat. The "inner surface" in the present text re^¬ fers to one side surface of respective support arm at least partially located in the enclosed space.

In one preferred embodiment, only a region of respective in- ner surface carrying the light source is located inside the enclosed space, and other portions of the heat sink, e.g. outer surface of respective support arm, are still located outside the enclosed space, so as to improve the heat dissi^¬ pating effect. In accordance with one preferred solution of the present in^¬ vention, respective support arm has the outer surface outside the enclosed space, and cooling ribs are arranged on the outer surface. The cooling ribs can be made in one piece with the support arm or additionally mounted on the support arm, thus, the heat dissipating area of the heat sink is in^¬ creased, so that heat can be dissipated, for instance, in a manner of radiation. In another preferred solution, the cooling ribs further can be replaced by other cooling structures such as cooling holes. The "outer surface" in the present text refers to one side surface formed opposite to the "inner surface" and located outside the enclosed space.

In accordance with one preferred solution of the present in^¬ vention, respective support arm has a hollow structure, with an accommodating cavity opened in the arm, for accommodating an electronic device for controlling the light source. Pref^¬ erably, respective electronic device can be, for instance, a flexible circuit board. The flexible circuit boards can be independent from each other and accommodated in the accommo^¬ dating cavities, respectively, so as to control the light sources. Wires further can be preferably used to electrically connect the light sources respectively mounted on the support arms with, e.g. a circuit board mounted on the base. Via the configuration of the hollow structure, spaces for accommodat^¬ ing the electronic devices are skillfully provided, reducing circuit complexity when the electronic devices are placed on the inner surfaces of the support arms.

In accordance with one preferred solution of the present in^¬ vention, the support arms in an odd number are provided.

There may be preferably three, five or more support arms. Upon experiments, the best heat dissipating and illuminating effects can be obtained when there are five support arms. In another preferred solution, the support arms further can be provided in pairs, for instance, there are two pairs, three pairs or more pairs of support arms.

In accordance with one preferred solution of the present in- vention, light source comprised a plurality of first light sources, and respective first light source is mounted in a first region of the inner surface facing away from the base, and the first region is a flat surface. At a free end of re^¬ spective support arm facing away from the base, the first re- gion located on an inner side of respective support arm, i.e. in the inner surface, is configured to mount the light source. In order to obtain good illuminating effect, respec^¬ tive first region is advantageously configured as flat sur^¬ face so that an optical path of the light source mounted thereon is directed to a central axis of the illuminating de^¬ vice. Since the illuminating device has a plurality of sup^¬ port arms, the first regions can be simply configured as flat surfaces, which not only can assure good omnidirectional il^¬ luminating effect, but also simplifies the manufacturing process of the heat sink at the same time.

In accordance with one preferred solution of the present in- vention, respective first region is perpendicular to the base, in which situation the optical path of the light source located in respective first region is parallel to the base and extends in the enclosed space. Preferably, respective first region is inclined with respect to the base, in which situation the first region can be, for instance, slightly in^¬ clined to the base until it forms an angle of 5° with the base, thus an illuminating effect close to omnidirectional illumination can be obtained. The light distribution effect of the illuminating device can be adjusted by adjusting the positional relation between the first regions and the base.

In one preferred embodiment, the first light sources mounted in the first regions are arranged in a form of point light sources. One or more first light sources can be mounted in respective first region according to demand to luminance. The "point light source" herein is a term in relation to the

"linear light source", specifically referring to that when an arrangement of a plurality of first light sources is de^¬ signed, they can be arranged, for instance, concentratedly or compactly into a ring shape or rectangular shape but not lin- ear shape.

Preferably, a single first light source is mounted in respec^¬ tive first region, thus the energy can be saved and the illu^¬ mination precision can be improved.

In accordance with one preferred solution of the present in- vention, the plurality of support arms are configured to have ,

b

an identical arc-shaped profile, and the arc-shaped profile matched with a profile of the bulb. The support arm config^¬ ured in such a manner has a high universality, and is par^¬ ticularly adapted to support a bulb usually configured to be pear-shaped or spherical. As a result, the illuminating de^¬ vice is pleasing, and the assembling process can be simplified .

In accordance with one preferred solution of the present in^¬ vention, the light source comprised at least one second light source , and a surface of the base facing the bulb comprises a second region for mounting the second light source. An op^¬ tical path of the second light source mounted in the second region advantageously can extend upwardly in a direction per^¬ pendicular to the base, and thus, when it is used simultane- ously with the first light sources in the first regions, a light angle of emergent light can be bigger than 180° in ver^¬ tical direction.

In accordance with one preferred solution of the present in^¬ vention, surfaces of the heat sink located inside the en- closed space are at least partially configured as reflective surfaces. By configuring a plurality of surfaces of the heat sink that can receive light in the enclosed space as reflec^¬ tive surfaces, the light efficiency of an illuminating device with such heat sink and the omnidirectional illuminating ef- feet can be improved.

In accordance with one preferred solution of the present in^¬ vention, the bulb is opened with a plurality of first open^¬ ings for at least partially accommodating the support arms, respectively, and a second opening corresponding to the sec- ond region, and the second opening and the first openings are in communication with each other. By opening the first open- ^

ings and the second opening that are in communication with each other on the spherical bulb, the bulb can be mounted on the heat sink and forms with the heat sink a complete and en^¬ closed illuminating device. In accordance with another preferred solution of the present invention, the bulb comprises an upper shell and a lower shell capable of being assembled together, wherein a circumferential wall of the upper shell is opened with a plurality of first openings for at least partially accommodating the support arms, respectively, and a second opening is opened in a center of the lower shell. As a result, the upper shell and the lower shell, when assembled into a complete bulb, further can be installed together with the heat sink so as to form the complete and enclosed illuminating device.

Respective support arm is clamped in respective first opening clamps corresponding. Since part of respective support arm, especially the first region of respective support arm, can be inserted into inside of the bulb through the first opening, the bulb clamps the support arms with the first openings in a horizontal direction, and meanwhile, the support arms, espe^¬ cially horizontal end surfaces thereof located between the inner surfaces and the outer surfaces, further support the bulb in a vertical direction with the first openings.

In accordance with one preferred solution of the present in- vention, the illuminating device further comprises a driver located in a cavity of the heat sink facing away from the bulb. Accordingly, the driver can be mounted in the heat sink in a compact manner, thus reducing the volume of the illumi^¬ nating device. Besides, the present invention further relates to an omnidi^¬ rectional luminaire, characterized by comprising the illumi^¬ nating device above. The omnidirectional illumination effect can be obtained by adjusting the number of light sources mounted in various regions of the illuminating device.

Further, the present invention further relates to a retrofit lamp which is an illuminating device according to the present invention taking LED chips as the light sources. The retrofit lamp in accordance with the present invention has the advan^¬ tages of energy saving and high efficiency.

Brief Description of the Drawings

The accompanying drawings constitute a part of the present Description and are used to provide further understanding of the present invention. Such accompanying drawings illustrate the embodiments of the present invention and are used to de^¬ scribe the principles of the present invention together with the Description. In the accompanying drawings the same compo^¬ nents are represented by the same reference numbers. As shown in the drawings:

Fig. 1 is a 3D exploded view of a first embodiment of an il^¬ luminating device in accordance with the present invention;

Fig. 2 is a sectional view of the first embodiment shown in Fig. 1; Fig. 3 is a 3D view of the first embodiment shown in Fig. 1 ; and

Fig. 4 is a 3D exploded view of a second embodiment of an il^¬ luminating device in accordance with the present invention. Detailed Description of the Embodiments

Fig. 1 is a 3D exploded view of a first embodiment of an il^¬ luminating device 100 in accordance with the present inven^¬ tion. The illuminating device 100 comprises a plurality of light sources 1, a bulb 2 and a heat sink 3. The heat sink 3 preferably serves dual functions of dissipating heat and pro^¬ viding support so as to support the bulb 2 and improve the heat dissipating effect of the illuminating device 100. The heat sink 3 comprises a base 4 and five support arms 5 ex- tending from a circumferential edge of the base 4. When the heat sink 3 and the bulb 2 are assembled into the complete illuminating device 100, the five support arms 5 of the heat sink 3 are partially inserted into the bulb 2, respectively, and define an enclosed space R for accommodating the light sources 1. The bulb 2 in the present embodiment consists of an upper shell 2.1 and a lower shell 2.2, wherein five first openings 11 are opened on a circumferential sidewall of the upper shell 2.1 for supporting on the heat sink 3 and accommodating the support arms 5, respectively, and a second open- ing 12 (see Fig. 2) that is not shown in Fig. 1 is opened in a center of the lower shell 2.2.

In the present embodiment, the five support arms 5 are uni^¬ formly distributed on the circumferential edge of the base 4, and one end of respective support arm 5 is connected with the circumferential edge, and the other end extends in a direc^¬ tion facing away from the base 4 and particularly extends following a profile curve of the bulb 2, so as to form a structure that can support the bulb 2. The light sources 1 comprise a plurality of first and second sources 1', 1''. The plurality of first sources 1 ' are mounted on inner surfaces 6 of the support arms 5. Heat generated in operation of the first light sources 1 ' can pass through the support arms 5 and be transferred directly in a thermal contact manner to various locations of the heat sink 3. There are, for in^¬ stance, two, three or four, preferably five or six or more support arms 5. On one hand, these support arms 5 provided in pairs or not in pairs can assure the illuminating device 100 to realize homogeneous and good illuminating effect, and on the other hand, they can meet desired heat dissipating re^¬ quirements based on a sufficiently big heat dissipating area. In addition, in order to further improve the heat dissipating effect, cooling ribs 8 are preferably arranged on surfaces of the support arms 5 exposed outside the enclosed space R, par^¬ ticularly on an outer surface 7 of respective support arm 5 formed opposite to the inner surface 6. The cooling ribs 8 can be made in one piece with the support arms 5, or addi- tionally arranged on the support arms 5.

In accordance with one embodiment of the present invention not shown, the cooling ribs further can be replaced by other cooling structures such as cooling holes so as to realize convective heat dissipation. The inner surface 6 of respective support arm 5 comprises an end region facing away from the base 4. This region is advantageously configured as a first region 9 for mounting the first light sources 1'. As shown in Fig. 2, a single first light sources 1 ' is mounted in respective first region 9, as a result, omnidirectional illumination can be realized with the five light sources mounted in the circumferential direc^¬ tion.

In a substitutable embodiment not shown, a plurality of first light sources 1 ' further can be mounted in respective first region 9. These first light sources 1' are arranged concen- tratedly or compactly into a ring shape or rectangular shape but not linear shape, so as to create an effect similar to that of "point light sources", and thus the light efficiency of the illuminating device 100 can be improved.

In order to power and control an operation state of the first light sources 1', electronic devices for controlling the first light sources 1 ' are placed in the accommodating cavi^¬ ties of the support arms 5 in the present embodiment. The electronic devices in the present embodiment are, for in^¬ stance, flexible circuit boards directly mounted into the ac- commodating cavities, respectively.

In other substitutable embodiments not shown, a circuit board is mounted on the base 4, and electronic devices are wires adapted to electrically connect first light sources 1 ' with the circuit board mounted on the base 4. In the first embodiment of the present invention, the support arms 5 are identically configured and each has an arc-shaped profile corresponding to an outer profile of the bulb 2. In the present embodiment, the base 4 is configured to have a truncated cone shape which can provide a curved surface with an area as big as is possible to be used as a functional sur^¬ face of the heat sink 3. A second region 10 for mounting the second sources 1 ' ' is formed in a center of a top surface of the base 4 so as to realize illumination in a vertical direc^¬ tion. For the sake of omnidirectional illuminating effect and coop^¬ eration with the circumferential profile of the bulb 2, the first region 9 is advantageously configured as a flat surface such that first light sources 1 ' mounted in various first re^¬ gions 9 illuminate in a radial direction towards a central axis of the illuminating device 100. The first regions 9 can be configured to be perpendicular to the second region 10, and further can be slightly inclined towards the second re^¬ gion 10 so as to realize illumination in horizontal and circumferential directions. The illuminating device 100 further comprises a driver lo^¬ cated in a cavity R' of the heat sink 3 facing away from the bulb. As a result, the driver can be mounted in the heat sink 3 in a compact manner, thus reducing the volume of the illu^¬ minating device 100. Fig. 2 is a sectional view of the first embodiment shown in

Fig. 1. It can be seen from Fig. 2 that the first openings 11 opened in the circumferential wall of the upper shell 2.1 hold corresponding support arms 5, respectively, and the up^¬ per shell 2.1 is assembled together with the lower shell 2.2 pressed against the base 4. Herein, only the first regions 9 are preferably located inside the enclosed space R, i.e. the first regions 9 and inner walls of the upper shell 2.1 and of the lower shell 2.2 define the enclosed space R, while other portions of the heat sink 3, such as outer surface 7 and side surfaces between the inner surface 6 and the outer surface 7 of respective support arm 5, are still located outside the enclosed space R, as a result, the heat dissipating effect can be improved. Besides, regions of the heat sink 3 located inside the enclosed space R, e.g. the first and second re- gions 9, 10, can be at least partially configured as reflec^¬ tive surfaces.

Fig. 3 is a 3D view of the first embodiment shown in Fig. 1. When the light sources 1 are LED chips, the illuminating de^¬ vice 100 can useful as retrofit lamp. In addition, since the illuminating device 100 can create omnidirectional illuminat^¬ ing effect, it further can be used as omnidirectional lumi- naire .

Fig. 4 is a 3D exploded view of a second embodiment of an il^¬ luminating device in accordance with the present invention. Different from the first embodiment, the bulb of the illumi- nating device 100 herein is configured as an independent part, e.g. pear-shaped bulb, and a plurality of first open^¬ ings 11 and one second opening 12 opened in the bulb 2 are in perpendicular communication. As the support arms 5 have a profile corresponding to that of the bulb 2, the inner sur- faces 6 can be completely located in the enclosed space R. All the inner surfaces 6 and the top surface of the base 4 herein can be preferably configured as reflective surfaces to improve the light efficiency.

The above is merely preferred embodiments of the present in- vention but not to limit the present invention. For the per^¬ son skilled in the art, the present invention may have vari^¬ ous alterations and changes. Any alterations, equivalent sub^¬ stitutions, improvements, within the spirit and principle of the present invention, should be covered in the protection scope of the present invention.

List of reference signs

1 light source

1 ' first light source

1 ' ' second light source

2 bulb

2.1 upper shell

2.2 lower shell

3 heat sink

4 base

5 support art

6 inner surface

7 outer surface

8 cooling rib

9 first region

10 second region

11 first opening

12 second opening

100 illuminating device

R enclosed space

R' cavity

Claims

Patent claims

1. An illuminating device (100), comprising a plurality of light sources (1), a bulb (2) and a heat sink (3), character- ized by that the heat sink (3) comprises a base (4) and a plurality of support arms (5) extending from a circumferen^¬ tial edge of the base (4), an inner surface of respective support arm (5) is mounted with a part of the light source (1), and the heat sink (3) is partially inserted into the bulb (2) with the plurality of support arms (5) and define an enclosed space (R) with the bulb (2) for accommodating the light sources (1) .

2. The illuminating device (100) according to Claim 1, characterized in that respective support arm (5) has an outer surface (7) outside the enclosed space (R) , and cooling ribs (8) are arranged on the outer surface (7) .

3. The illuminating device (100) according to Claim 1, characterized in that respective support arm (5) has a hollow structure, with an accommodating cavity opened in the arm, for accommodating an electronic device for controlling the light source ( 1 ) .

4. The illuminating device (100) according to Claim 3, characterized in that respective electronic device is a flexible circuit board.

5. The illuminating device (100) according to Claim 1, characterized in that the support arms (5) in an odd number are provided.

6. The illuminating device (100) according to Claim 4, characterized in that five support arms (5) are provided.

7. The illuminating device (100) according to Claim 1, characterized in that light source (1) comprised a plurality of first light sources (1'), and respective first light source (1') is mounted in a first region (9) of the inner surface (6) facing away from the base (4), and the first re^¬ gion (9) is a flat surface.

8. The illuminating device (100) according to Claim 7, characterized in that respective first region (9) is perpen^¬ dicular to the base (4) .

9. The illuminating device (100) according to Claim 7, characterized in that respective first region (9) is inclined with respect to the base (4) .

10. The illuminating device (100) according to Claim 7, characterized in that the first light sources (1') mounted in the first regions (9) are arranged in a form of point light sources.

11. The illuminating device (100) according to Claim 10, characterized in that a single first light source (1') is mounted in respective first region (9) .

12. The illuminating device (100) according to any one of Claims 1-7, characterized in that the plurality of support arms (5) are configured to have an identical arc-shaped pro^¬ file, and the arc-shaped profile matched with a profile of the bulb (2 ) .

13. The illuminating device (100) according to any one of Claims 1-7, characterized in that the light source (1) com^¬ prised at least one second light source (1''), and a surface of the base (4) facing the bulb (2) comprises a second region (10) for mounting the second light sources (1'').

14. The illuminating device (100) according to Claim 13, characterized in that the bulb (2) is opened with a plurality of first openings (11) for at least partially accommodating the support arms (5), respectively, and a second opening (12) corresponding to the second region (12), and the second opening (12) and the plurality of first openings (11) are in com^¬ munication with each other.

15. The illuminating device (100) according to Claim 13, characterized in that the bulb (2) comprises an upper shell

(2.1) and a lower shell (2.2) capable of being assembled to^¬ gether, wherein a circumferential wall of the upper shell

(2.1) is opened with a plurality of first openings (11) for at least partially accommodating the support arms (5) , and a second opening (12) is opened in a center of the lower shell

(2.2) .

16. The illuminating device (100) according to Claim 14 or 15, characterized in that respective support arm (5) is clamped in respective first opening (11) .

17. The illuminating device (100) according to any one of Claims 1-7, characterized in that surfaces of the heat sink (3) located inside the enclosed space (R) are at least par^¬ tially configured as reflective surfaces.

18. The illuminating device (100) according to any one of Claims 1-7, characterized by further comprising a driver lo^¬ cated in a cavity (R' ) of the heat sink (3) facing away from the bulb (2 ) .

19. An omnidirectional luminaire, characterized by compris- ing the illuminating device (100) according to any one of Claims 1-18.

20. A retrofit lamp, characterized by comprising the illumi^¬ nating device (100) according to any one of Claims 1-18, whe- rein the light sources (1) are LED chips.