Heat Dissipating Device, and Illuminating Device Technical Field

The present invention relates to a heat dissipating device, and an illuminating device.

Background Art

With the development of the illuminating technology, LED il- luminating devices are popular due to their advantages, such as energy saving which has become a main theme in the current world. As they save energy, the LED illuminating devices rap ^¬ idly develop in the last decade.

A complete LED illuminating system usually comprises compo- nents such as driver, LED chip, housing, heat dissipating device, and optical assembly. Among the components, both the driver and the LED chip generate much heat. LED retrofit lamps particularly require good heat dissipating performances, which are quite important. The lower the temperature is, the higher the luminous efficiency is. If the temperature is too high, the service lifetime of the optoelectronic com ^¬ ponents will be greatly shortened and failure will occur.

In the prior art, during the fabrication, an aluminum-made LED heat dissipating device mainly is acquired by die-casting process or is machined after extrusion. In the past few years, people develop some processing technologies such as die-casting. The die-casting can guarantee a high quality and a long service lifetime of the product. Another advantage is that the heat dissipating device can have a quite complex shape and a high shape stability, and it is capable of real ^¬ izing good heat dissipating capabilities with different thicknesses and good availability of suppliers, while the shortcomings are that the heat dissipating device made via die-casting has a larger weight than that made from a metal sheet, moreover, depending upon different processes and used materials, a minimum wall thickness at least should be 2-3mm, and an angle for demoulding is necessary.

It is also provided in the prior art that the heat dissipat- ing device is made via an extrusion process. Most extrusions are made in large hydraulic press that uses a specifically shaped mould to form parts. The size of the press depends upon the tonnage and the maximum circle size of the mould. The maximum circle size of the mould limits the size of the maximum profile. The circle size of the press ranges from about 2.0 inches to as large as 30.0 inches. In general, the larger the mould is, the smaller the number of presses avail ^¬ able in the world is. It has the advantage of being cheaper than the die casting, while the shortcoming is that machining is needed after extrusion, and the section profile cannot be too complex according to requirements of the extrusion proc ^¬ ess.

Therefore, how to break through the limits in size and sec ^¬ tion profile have become urgent problems to be addressed in the heat dissipating device.

Summary of the Invention

Therefore, the object of the present invention lies in pro ^¬ viding a heat dissipating device that can overcome defects of various prior solutions and has the advantages of a simple manufacturing process, a low cost, a light weight, capability of breaking through limits in size and section profile to some extent, and prominently improved heat dissipating abil ^¬ ity.

A heat dissipating device for an illuminating device is pro- vided according to the first aspect of the present invention, characterized in that the heat dissipating device comprises a first bottom wall and a first circumferential wall that are configured to define a first cavity opened at one side, the first bottom wall is at least partially deformed to form a second bottom wall and a second circumferential wall that are configured to define a second cavity opened at one side, and the first bottom wall, the first circumferential wall, the second bottom wall and the second circumferential wall are made in one piece from a metal sheet via a spinning process. As the heat dissipating device of the present invention is made from a metal sheet, in one piece via the spinning or deep-drawing process, the weight thereof is significantly re ^¬ duced; and since the metal sheet has a good heat dissipating performance, the whole heat dissipating performance of the heat dissipating device is quite favorable. In addition, a mould used in the spinning or deep-drawing process is not too expensive, so that the manufacturing cost of the heat dissi ^¬ pating device is also greatly reduced. Besides, a heat dissi ^¬ pating device having the first bottom wall, the first circum- ferential wall, the second bottom wall and the second circum ^¬ ferential wall for an illuminating device, made via the spin ^¬ ning or deep-drawing process, can be arranged with a first heat source such as light-emitting assembly in the second cavity or the first cavity, at which time, the first cavity or the second cavity also can be at least partially arranged with a driver, and as a result, the heat dissipating require ^¬ ments of different heat sources of an LED illuminating de- vice, especially a retrofit lamp, are satisfied.

The heat dissipating device is made from Al that has advan ^¬ tages of a light weight and good heat dissipating capabili ^¬ ties. Al materials include, but not limited to, Al 1050, Al 1060 and A11070.

Preferably, surfaces of the first bottom wall, the first circumferential wall, the second bottom wall and the second circumferential wall are processed by Al anodizing or elec- trocoating. Walls undergone the Al anodizing or electrocoat- ing can prevent oxidation.

Preferably, a plurality of first ventilation holes are formed in a region of the first bottom wall that is not deformed and/or a plurality of second ventilation holes are formed on the first circumferential wall. Accordingly, the heat dissi- pating device provides heat dissipation through convection via the ventilation holes.

Preferably, the plurality of first ventilation holes and/or the plurality of second ventilation holes are formed via a punching process which has advantages of a low cost and easy implementation.

Preferably, the second cavity or the first cavity is arranged with a heat source.

In one preferred solution of the present invention, the first bottom wall is spun or deep-drawn towards the first circum- ferential wall so as to form the second cavity. This pre ^¬ ferred solution is suited to create the second cavities that are "deformed back" with respect to the first cavity. Preferably, a thermal conductive silicon glue is filled in the second cavity or the first cavity arranged with the light-emitting assembly, and the thermal conductive silicon glue is not higher than a plane where the light-emitting as- sembly is located, so that heat generated by the heat source passes the thermal conductive silicon glue to be transferred to the second circumferential wall or the first circumferen ^¬ tial wall. The heat dissipating device provides transfer heat dissipation through the thermal conductive silicon glue. Preferably, the heat source is a light-emitting assembly, and the second bottom wall is configured to support the light- emitting assembly. The light-emitting assembly is placed in the first cavity or the second cavity and supported on the second bottom wall. Therefore, the heat dissipating device in this case can be used as an independent heat dissipating de ^¬ vice to serve both functions of dissipating heat and support ^¬ ing the light-emitting assembly.

In another alternative preferred solution of the present in ^¬ vention, the first bottom wall is spun or deep-drawn away from the first circumferential wall so as to form the second cavity. This preferred solution is suited to create the sec ^¬ ond cavities that are "stretched" with respect to the first cavity .

At this time, the heat source is an LED driver, the second bottom wall and the second circumferential wall form a driver housing as the second cavity for accommodating the LED driver, and the second bottom wall is opened with an opening. The heat dissipating device in this case can be regarded as comprising the driver housing integrated therewith. Preferably, a pin assembly comprising an insulation pad and pins inserted into the insulation pad is provided in the opening for preventing short circuit between the pins and the driver housing.

An illuminating device is provided according to the second aspect of the present invention, comprising the heat dissi ^¬ pating device having the above characteristics.

An illuminating device is provided according to the third as ^¬ pect of the present invention, comprising a heat dissipating device at least having the following features, wherein the first bottom wall is spun or deep-drawn away from the first circumferential wall to form the second cavity, the second cavity of the heat dissipating device is used as a driver housing. At this time, the illuminating device further comprises a cover pressed on the first circumferential wall for supporting a light-emitting assembly or other optical parts, that is, the heat dissipating device has a driver housing made in one piece with the heat dissipating device.

An illuminating device is provided according to the fourth aspect of the present invention, comprising a heat dissipat- ing device at least having the following features, wherein the first bottom wall is spun or deep-drawn towards the first circumferential wall to form the second cavity, the second cavity or the first cavity of the heat dissipating device is used as an accommodating cavity of a light-emitting assembly. The illuminating device further comprises a driving housing. The second cavity or the first cavity of the heat dissipating device is used as an accommodating cavity of a light-emitting assembly, and the driver housing is connected onto the first circumferential wall or the second circumferential wall. A driver housing known in the prior art can be used as the driver housing in the present embodiment. The illuminating device is an LED retrofit lamp.

A method for processing a heat dissipating device is provided according to the fifth aspect of the present invention, characterized by comprising steps of: a) providing a metal sheet, b) deep-drawing or spinning the metal sheet into a cylinder part having a first bottom wall and a first circumferential wall opened at one side, deep-drawing or spinning the first bottom wall to form a second bottom wall and a second circum ^¬ ferential wall. According to an improved solution of the present invention, the method further comprises, after step b) , a step of c) forming a plurality of first ventilation holes in a region of the first bottom wall that is not deformed and/or forming a plurality of second ventilation holes on the first circumfer- ential wall via a punching process.

According to an improved solution of the present invention, the method further comprises, after step c) , a step of d) necking the first circumferential wall to form a taper-like shape of the first circumferential wall so as to define a second cavity opened at one side.

The heat dissipating device of the present invention has the advantages of a simple manufacturing process, a low cost, a light weight, capability of breaking through limits in size and section profile to some extent, and prominently improved heat dissipating ability.

It shall be understood that both the above general descrip ^¬ tion and the following detailed description are for illustrative and explanative purposes in order to provide further de ^¬ scription of the claimed present invention. 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 section view of a heat dissipating device of a first exemplary embodiment of the present invention;

Fig. 2 is an assembled diagram of an illuminating device of the present invention installed with the heat dissipating de ^¬ vice of the first exemplary embodiment of the present inven- tion;

Fig. 3 is a section view of a heat dissipating device of a second exemplary embodiment of the present invention;

Fig. 4 is a section view of a heat dissipating device of a third exemplary embodiment of the present invention; Fig. 5 is an assembled diagram of an illuminating device of the present invention installed with the heat dissipating de ^¬ vice of the third exemplary embodiment of the present inven ^¬ tion;

Fig. 6 is a section view of a heat dissipating device of a fourth exemplary embodiment of the present invention;

Fig. 7a and Fig. 7b are a section view and an exploded assem- bling diagram of an illuminating device of the present invention installed with the heat dissipating device of the fourth exemplary embodiment of the present invention, respectively;

Fig. 8 is a schematic diagram of an application of an exem- plary embodiment of a heat dissipating device of the present invention; and

Figs. 9a-9d are schematic diagrams of flow of a method for processing the heat dissipating device in the first to the third exemplary embodiments of the present invention. Detailed Description of the Embodiments

Fig. 1 is a section view of a heat dissipating device 10 of a first exemplary embodiment of the present invention; and Fig. 2 is an assembled diagram of an illuminating device 100 of the present invention installed with the heat dissipating de- vice 10 of the first exemplary embodiment of the present in ^¬ vention. It can be seen from Fig. 1 that the heat dissipating device 10 comprises a plurality of walls, namely, a first bottom wall 1, a first circumferential wall 2, a second bot ^¬ tom wall 4 and a second circumferential wall 5. All of these walls are made in one piece from the same metal sheet via a spinning or deep-drawing process. The first bottom wall 1 and the first circumferential wall 2 jointly define a first cav ^¬ ity 3 opened at one side, and the second bottom wall 4 and the second circumferential wall 5 jointly define a second cavity 6 opened at one side. It should be indicated that one part of the first bottom wall 1 is spun or deep-drawn to form the second bottom wall 4 and the second circumferential wall 5. The first bottom wall 1 is spun or deep-drawn towards the first circumferential wall 2 so as to form the second cavity 6, that is, the first cavity 3 is reduced by spinning or deep-drawing the first bottom wall 1 towards the first cavity 3, so as to form the second cavity 6. The heat dissipating device 10 in this exemplary embodiment mainly serves the functions of dissipating heat and carrying a light-emitting assembly. The heat dissipating device 10 is made form Al, and also can be made from other metals having a good heat dissi ^¬ pating capability and a light weight. Surfaces of the first bottom wall 1, the first circumferential wall 2, the second bottom wall 4 and the second circumferential wall 5 are proc- essed by Al anodizing or electrocoating to prevent the surfaces of the walls from oxidation.

In conjunction with Fig. 2, it can be seen that the heat dissipating device 10 in this embodiment is mainly used for ar ^¬ rangement of a light-emitting assembly 23. As shown in Fig. 2, the illuminating device 100 comprises the light-emitting assembly 23, and the light-emitting assembly 23 comprises a circuit board 13, an LED chip 14 arranged on the circuit board 13 and a lens 17 arranged on the LED chip 14. A cover 18 is placed in an upper side of the heat dissipating device 10. The light-emitting assembly 23 is arranged on the second bottom wall 4 in the first cavity 3, and a thermal conductive silicon glue 12 is filled between the light-emitting assembly 23 and the first circumferential wall 5, and the thermal con ^¬ ductive silicon glue 12 is not higher than a plane where the light-emitting assembly 23 is located for preventing influ ^¬ ence of light. In this exemplary embodiment, only the heat dissipating device 10 per se is made in one piece, and a driver housing 9 accommodating an LED driver 11 also can be formed in other known prior manners. The driver housing 9 can be installed from below the heat dissipating device 10 on the second circumferential wall 5 of the heat dissipating device 10 and forms a streamline shape with the second circumferen ^¬ tial wall 5 of the heat dissipating device 10. Fig. 3 is a section view of a heat dissipating device 10 of a second exemplary embodiment of the present invention. The second exemplary embodiment is substantially the same as the first exemplary embodiment, while the difference lies in that the heat dissipating device 10 is processed in a front proc ^¬ essing style, i.e., a mode of processing from top to bottom, and the heat dissipating device 10 in the first exemplary em ^¬ bodiment is processed in a rear processing style, i.e., a mode of processing from bottom to top. At this time, the light-emitting assembly 23 can be considered to be arranged on the second bottom wall 4 of the second cavity 6, and a driving housing 9 known in the prior art can be mounted on the first circumferential wall 2.

Fig. 4 is a section view of a heat dissipating device 10 of a third exemplary embodiment of the present invention. The third exemplary embodiment is substantially the same as the first exemplary embodiment, while the difference lies in that the degree to which the first bottom wall 1 of the heat dis ^¬ sipating device 10 is spinned or deep-drawn is deeper, thus resulting in a higher height of the second cavity 6; more ^¬ over, more parts of the first bottom wall 1 are spinned or deep-drawn, and only a small quantity of parts of the first bottom wall 1 remain not spinned or deep-drawn.

Fig. 5 is an assembled diagram of an illuminating device 100 of the present invention installed with the heat dissipating device 10 of the third exemplary embodiment of the present invention. It can be seen from Fig. 5 that the heat dissipat ^¬ ing device 10 is also used to carry the light-emitting assembly 23, and the second cavity 6 can accommodate most of the LED driver 11. Besides, different from that shown in Fig. 2, a lamp cover 15 additionally equipped to the illuminating de ^¬ vice 100 for diffusing light is different from the flat- shaped cover 18 shown in Fig. 2. Fig. 5 also shows that the LED driver 11 is connected to an electric plug 16 up to a power supply.

Fig. 6 is a section view of a heat dissipating device 10' of a fourth exemplary embodiment of the present invention. This heat dissipating device 10' is slightly different from that in the three exemplary embodiments above. It can be seen from Fig. 6 that the heat dissipating device 10' has a plurality of walls, namely, a first bottom wall 1, a first circumferen- tial wall 2, a second bottom wall 4 and a second circumferen ^¬ tial wall 5. All of these walls are made in one piece from the same metal sheet via a spinning, or preferably, a deep- drawing process. The first bottom wall 1 and the first circumferential wall 2 jointly define a first cavity 3 opened at one side, and the second bottom wall 4 and the second circumferential wall 5 jointly define a second cavity 6 opened at one side. It should be indicated that one part of the first bottom wall 1 is spun or deep-drawn to form the second bottom wall 4 and the second circumferential wall 5. Different from that in the three exemplary embodiments above, the first bottom wall 1 is spun or deep-drawn away from the first circumferential wall 2 so as to form the second cavity 6, that is, the second cavity 6 is formed by spinning or deep-drawing the first bottom wall 1 away from the first cav- ity 3. The second cavity 6 is used as the driver housing 9, and the other walls 2 of the heat dissipating device 10' are used for heat dissipation. The driver housing 9 not only accommodates the LED driver 11, but also increases the heat dissipating area so as to improving the heat dissipating function. The heat dissipating device 10' in this exemplary embodiment integrates heat dissipating parts and the driver housing 9 and mainly serves the functions of dissipating heat and accommodating the driver housing. A plurality of second ventilation holes 8 are opened on the first circumferential wall 2 for realizing heat dissipation through convection.

Fig. 7a and Fig. 7b are a section view and an exploded assembling diagram of an illuminating device 100 of the present invention installed with the heat dissipating device 10' of the fourth exemplary embodiment of the present invention, re ^¬ spectively. In conjunction with Fig. 7a, it can be seen that the heat dissipating device 10' in this embodiment is mainly used for arrangement of the light-emitting assembly 23. As shown in Fig. 7a, the illuminating device 100 comprises the light-emitting assembly 23, and the light-emitting assembly 23 comprises a circuit board 13, an LED chip 14 arranged on the circuit board 13 and a lens 17 arranged on the LED chip 14. A cover 18 is placed in an upper side of the heat dissi- pating device 10'. In this exemplary embodiment, the heat dissipating device 10' comprises a driver housing 9 formed in one piece for accommodating an LED driver 11. An opening 21 is opened on the second bottom wall 4, and a pin assembly comprising an insulation pad 19 and pins 20 inserted into the insulation pad 19 is provided in the opening 21. The insula ^¬ tion pad 19 is used for electrical insulation. In conjunction with Fig. 7b, it can be seen that the cover 18 can be an annular cover with a plurality of ventilation holes distributed thereon. The lens 17, an LE locating plate 22, the cover 18, the circuit board 13, the insulation pad 19 and the pins 20 inserted into the insulation pad 19 can be installed sequen ^¬ tially in the heat dissipating device 10'.

Fig. 8 is a schematic diagram of an application of an exemplary embodiment of a heat dissipating device of the present invention. Fig. 8 schematically shows an upper housing part 31 at upper side and a lower housing part 32 at a lower side in cooperation with each other. In a first application situa- tion, the housing part at the upper side can be configured as a variant of the heat dissipating device according to any one of the first to the third exemplary embodiments, while the lower housing part, i.e., driver housing, at the lower side in cooperation with the upper housing part is a driver housing, made from a plastic, known in the art. The driver hous ^¬ ing also can be made through an injection molding process and has a profile similar to the fourth embodiment of the heat dissipating device of the present invention. The driver hous- ing has ventilation holes for convective heat dissipation with ventilation holes opened on the upper housing part 31. In a second application situation, the lower housing part 32 at the lower side is configured as a variant of the heat dis ^¬ sipating device according to the fourth exemplary embodiment, while the upper housing part at the upper side in cooperation therewith can be made from a plastic and has a profile simi ^¬ lar to the heat dissipating device of any one embodiment of the first to the third exemplary embodiments. The upper hous ^¬ ing part 31 herein can be understood as another variant of a cover. In the two application situations, the upper housing part and the lower housing part can be opened with ventila ^¬ tion holes, respectively, to realize convective heat dissipa ^¬ tion. Moreover, a buckle 24 formed on one of the upper hous ^¬ ing part and the lower housing part and a groove 24' on the other one of the housing parts can be used for realizing mutual locking.

Figs. 9a-9d are schematic diagrams of flow of a method for machining the heat dissipating device 10 in the first to the third exemplary embodiments of the present invention. The method comprises steps of: firstly, providing a metal sheet (Fig. 9a); secondly, deep-drawing or spinning the metal sheet, via a deep-drawing or spinning process, into a cylinder part having a first bottom wall 1 and a first circumfer- ential wall 2 opened at one side, and deep-drawing or spin ^¬ ning the first bottom wall 1 via the deep-drawing or spinning process to form a second bottom wall 4 and a second circum ^¬ ferential wall 5 (Fig. 9b); thirdly, forming a plurality of first ventilation holes 7 in a region of the first bottom wall 1 that is not deformed via a punching process, alterna ^¬ tively, forming a plurality of second ventilation holes 8 on the first circumferential wall 2 via a punching process in this step; and finally, necking the first circumferential wall 7 to form a taper-like shape of the first circumferen ^¬ tial wall 7, and finally forming a second cavity 6; and thereafter, surfaces of the first bottom wall 1, the first circumferential wall 2, the second bottom wall 4 and the sec ^¬ ond circumferential wall 5 are processed by Al anodizing or electrocoating . It should be indicated that the method in the fourth exemplary embodiment is substantially the same as that shown in Figs. 9a-9d, while the difference lies in a differ ^¬ ent mould used in forming the driver housing 9 and a different spinning or deep-drawing direction in the second step. 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

10, 10' heat dissipating device

100 illuminating device

1 first bottom wall

2 first circumferential wall

3 first cavity

4 second bottom wall

5 second circumferential wall 6 second cavity

7 first ventilation hole

8 second ventilation hole

9 driver housing

11 LED driver

12 thermal conductive silicon glue

13 circuit board

14 LED chip

15 lamp cover electric plug

lens

cover

insulation pad

pin

opening

LE locating plate light-emitting assembly buckle

groove

upper housing part lower housing part