Background technology
In the LED lighting that prior art provides, as shown in Figure 1, led chip places packaging body 11, packaging body 11 bonds on the wiring board on metal PCB substrate 13 upper stratas by solder(ing) paste 12, the aluminium base copper-clad plate of this metal PCB substrate 13 general employings, design has the conducting wire that connects a plurality of led chips on this wiring board, and this conducting wire while is as the main thoroughfare of led chip heat conduction.The metal PCB substrate 13 of above-mentioned carrying packaging body is fixed on the fin 15 by heat-conducting glue 14.
Adopt the LED lighting of said structure, it is easy to assembly, yet just whole heat dispersion has certain defective.Computing formula by overall thermal resistance:
Wherein, temperature difference T
Junction-AmblentBe poor (K) of packaging body 11 temperature inside and ambient temperature, P
dIt is whole dissipation power (W), its value equals whole voltage (V) and multiply by electric current (A), as can be known, under the situation that ambient temperature is fixed, overall thermal resistance is big more, be illustrated under the same dissipation power, packaging body 11 temperature inside are high more, so just mean that the luminous efficiency of led chip is low more, useful life is short more.
And the thermal resistance, packaging body 11 that the overall thermal resistance of structure shown in Figure 1 comprises led chip by solder(ing) paste 12 to the thermal resistance of metal PCB substrate 13, metal PCB substrate 13 by the thermal resistance of heat-conducting glue 14 to the thermal resistance of fin 15 and fin 15 to external environment condition, because there is thermal resistance by solder(ing) paste 12 in metal PCB substrate 13 between packaging body 11, make that the overall thermal resistance under this structure is bigger, and then cause packaging body 11 temperature inside to raise, in conjunction with above-mentioned analysis as can be known, adopt this kind structure to reduce the luminous efficiency of led chip and the useful life of led chip.
The utility model content
The purpose of this utility model is to provide a kind of LED encapsulation unit, be intended to solve in the LED lighting that prior art provides, the packaging body that includes led chip bonds on the wiring board on metal PCB substrate upper strata by solder(ing) paste, because there is thermal resistance by solder(ing) paste in metal PCB substrate between the packaging body, the luminous efficiency of led chip and the problem in led chip useful life have been reduced.
The utility model is achieved in that a kind of LED encapsulation unit, comprises one or more led chips, and the positive pole of described led chip and negative pole are electrically connected with the support of being made by conductive heat conducting material respectively.
In above-mentioned LED encapsulation unit, described LED encapsulation unit comprises a plurality of led chips, and described a plurality of led chips are connected in parallel and/or are connected in series by described support.
Further, when described a plurality of led chips were connected in parallel, the positive pole of described a plurality of led chips connected by described support, and described a plurality of led chip negative poles connect by described support.
Further, when described a plurality of led chips were connected in series, described a plurality of led chips were by the connection in sequential series of described support.
Further, when described a plurality of led chips are when being connected in series and being connected in parallel, described a plurality of led chips adopt matrix-style to connect by described support; Led chip on the described matrix on each row is connected in series mutually, and each led chip that lists all is connected in parallel on the described matrix.
Further, described LED encapsulation unit also comprises a heat abstractor, described a plurality of led chip is arranged at the same surface of described support, and the surperficial relative surface with being provided with described led chip of described support is connected with described heat abstractor by solder(ing) paste or heat-conducting glue.
Further, described led chip is located in the reflector.
Further, the subtended angle of described reflector is 20 degree-145 degree.
Further, described reflector contacts with described heat abstractor surface towards the one side of described heat abstractor, and described led chip is connected with described reflector the perforation by Heat Conduction Material with one side described heat abstractor contact towards the one side of described heat abstractor.
Another purpose of the utility model embodiment is to provide a kind of LED light-emitting device, comprises a LED encapsulation unit, and described LED encapsulation unit adopts aforesaid LED encapsulation unit.
The LED encapsulation unit that the utility model embodiment provides comprises one or more led chips, the positive pole of this led chip and negative pole directly are electrically connected with the support of being made by conductive heat conducting material respectively, thereby avoided employing packaging body and wiring board to weld, and then reduced packaging body by solder(ing) paste to the thermal resistance between the support, improved the luminous efficiency of led chip, and prolonged useful life of led chip, and the user can realize the connection in series-parallel of requisite number purpose led chip by the diverse location that cuts off support, easy and simple to handle, improved the packaging efficiency of led chip.
Embodiment
In order to make the purpose of this utility model, technical scheme and advantage clearer,, the utility model is further elaborated below in conjunction with drawings and Examples.Should be appreciated that specific embodiment described herein only in order to explanation the utility model, and be not used in qualification the utility model.
Because in the existing LED lighting, metal PCB substrate has reduced luminous efficiency and led chip useful life of led chip to the thermal resistance that exists between the packaging body by solder(ing) paste, for addressing this problem, in the LED encapsulation unit that the utility model embodiment provides, led chip is directly fixed on the support of being made by conductive heat conducting material, avoided employing packaging body and wiring board to weld, and then reduced packaging body by solder(ing) paste to the thermal resistance between the support, improve the luminous efficiency of led chip, and prolonged the useful life of led chip.
Fig. 1 is the side structure schematic diagram of the encapsulation unit of the LED that provides of the utility model embodiment, and Fig. 3 is the profile of Fig. 2, for convenience of explanation, only shows the part relevant with the utility model embodiment.
As shown in Figures 1 and 2, the LED encapsulation unit that the utility model embodiment provides comprises one or more led chips 21, the positive pole of this led chip and negative pole are electrically connected with the support of being made by conductive heat conducting material 22 respectively, thereby avoided the employing packaging body, and then reduced packaging body by solder(ing) paste to the thermal resistance between the support, improve the luminous efficiency of led chip, and prolonged the useful life of led chip.Particularly, the both positive and negative polarity of led chip can be realized and being connected of support 22 by solder(ing) paste or heat-conducting glue or other material respectively.
Wherein, when the LED encapsulation unit comprised a plurality of led chip, these a plurality of led chips can be connected in parallel and/or be connected in series by support 22, when a plurality of led chips are connected in parallel, the positive pole of a plurality of led chips connects by support 22, and a plurality of led chip negative poles connect by support 22; When a plurality of led chips were connected in series, a plurality of led chips were by support 22 connections in sequential series.
When practical application, the user can realize series-parallel connection of requisite number purpose led chip by the diverse location that directly cuts off support 22, for example, the user can be according to the size of power and the needs of circuit, support 22 is cut into certain shape, and to the encapsulating structure coupling of the definite shape that obtains with corresponding power supply, easy and simple to handle, improved the packaging efficiency of led chip; In addition, for a plurality of led chips that are connected in parallel, because the positive pole of a plurality of led chips all is electrically connected by support 22, the negative pole of a plurality of led chips all is electrically connected by support 22, therefore, can be by the support that connects anodal support or connection negative pole be tested, whether a plurality of led chips that are connected in parallel with inspection are qualified, compare with respect to traditional need testing, reduced the testing time single LEDs chip.
Further, when a plurality of led chips are when being connected in series and being connected in parallel, a plurality of led chips can adopt matrix-style to pass through support 22 and realize connecting, as shown in Figure 4, wherein, led chip on the matrix on each row is connected in series mutually, and correspondingly each led chip that lists all is connected in parallel on the matrix.
In order to make the heat in led chip when work in time to distribute, the encapsulation unit that the utility model embodiment provides also further comprises a heat abstractor 23, one or more led chips are arranged at the same surface of support 22, can the realizing and being connected of heat abstractor 24 by solder(ing) paste or heat-conducting glue or other material with a surperficial relative surface that is provided with led chip of support 22.
In order to improve the luminous light efficiency of led chip, among the utility model embodiment, led chip 21 is located in the reflector 24.Wherein, the subtended angle of reflector 24 is preferably 20-145 °, and reflector 24 can be passed through at injection moulding of led chip edge or some gum forming by resistant to elevated temperatures plastic cement or modified silica-gel.Because reflector 24 can reflect the light that led chip 21 sends, therefore, this independently reflector 24 can promote the light efficiency of led chip 21 more than 25%; In addition, when this encapsulation unit comprises a plurality of led chip,, can reduce the stress requirement like this, can need crooked place so that product is used in simultaneously, have certain pliability because the corresponding reflector of a plurality of led chips is relatively independent.
Further, in order when adopting reflector 24 and heat abstractor 23, can further to improve the thermal diffusivity of led chip, among the utility model embodiment, reflector 24 contacts with heat abstractor 23 surfaces towards the one side of heat abstractor 23, led chip is connected with reflector 24 perforation by Heat Conduction Material with one sides heat abstractor 23 contacts towards the one side of heat abstractor 24, so that the heat that led chip produces in the course of the work can directly be passed to the surface of heat abstractor 23 by this Heat Conduction Material, thereby make heat in time to shed.
In addition, in order to reduce product cost, support 22 is based on copper material, by this copper material being carried out punching press to form required circuit, and on this copper material, plate the metal level that can bonding wire has thermal conductivity again, in order to improve the reflectivity of led chip, this metal level can also have higher reflectivity (as silver layer etc.) simultaneously.Afterwards with the PPA injection mo(u)lding on this copper material, to form independently reflector.Because copper material and PPA material etc. all are easy to obtain, thereby reduced the whole cost that produces this.
Certainly, during specific implementation, support 22 can also be based on metal substrate, by on metal substrate, making circuit, afterwards at LED edge independently by with plastic cement with the mode that penetrates obtain reflector or with the mode of glue material by a glue around it naturally the formation reflector form.As Fig. 5 is among the utility model embodiment, when support adopts matrix-style to be arranged on the substrate based on metal substrate and a plurality of led chip the surface texture schematic diagram, plastic cement wherein specifically can be PPA, and glue material wherein specifically can be a modified silica-gel.In order to promote the heat radiation level of product integral body, this metal substrate can also be replaced by traditional FR4 substrate, covers copper afterwards on this substrate.
The utility model embodiment also provides a kind of LED light-emitting device, comprises as mentioned above a LED encapsulation unit.
The LED encapsulation unit that the utility model embodiment provides comprises one or more led chips, the positive pole of this led chip and negative pole directly are electrically connected with the support of being made by conductive heat conducting material respectively, thereby avoided employing packaging body and wiring board to weld, and then reduced packaging body by solder(ing) paste to the thermal resistance between the support, improved the luminous efficiency of led chip, and prolonged useful life of led chip, and the user can realize the connection in series-parallel of requisite number purpose led chip by the diverse location that cuts off support, easy and simple to handle, improved the packaging efficiency of led chip; Have again, when this LED encapsulation unit comprises a plurality of led chips, and when a plurality of led chips are connected in parallel, can be by the support that connects anodal support or connection negative pole be tested, whether a plurality of led chips that are connected in parallel with inspection are qualified, compare with respect to traditional need testing, reduced the testing time single LEDs chip; Have, this LED encapsulation unit also comprises heat abstractor again, and the heat that produces in the time of led chip can being worked is in time derived; Have, led chip is located in the reflector again, has increased the luminous light efficiency of LED; Further, led chip is connected with reflector the perforation by Heat Conduction Material with the one side heat abstractor contact towards the one side of heat abstractor, so that the heat that led chip produces in the course of the work can directly be passed to the surface of heat abstractor by this Heat Conduction Material, further improved the thermal diffusivity performance.
The above only is preferred embodiment of the present utility model; not in order to restriction the utility model; all any modifications of within spirit of the present utility model and principle, being done, be equal to and replace and improvement etc., all should be included within the protection range of the present utility model.