Patent Application
20140204582
1. Field of the Invention
The present invention relates generally to lighting device's structure, and more particularly to an illuminating apparatus which has a good thermal dissipation performance.
2. Description of the Related Art
Light emitting diode (LED) is widely used in the present days because of its small size, low power consumption, high efficiency, and long lifespan.
1. The size of the MCPCB 3 is limited by the cover 5, and therefore the LEDs 4 on the MCPCB 3 are very crowded, so that the conventional LED bulb 1 is very hot, and the heat is hard to dissipate. It will reduce the illumination efficiency and shorten the LED bulb's 1 life. The problem is even worse for a high lumens LED bulb.
2. Although the base 2 is made of aluminum, which is good at thermal dissipation, but the base 2 only has a very small area in touch with the MCPCB 3 and a dissipating surface 2a is far away from the MCPCB 3, so that the conventional LED bulb 1 only has poor thermal dissipation performance. Besides, the aluminum base 2 is very expensive.
3. The base 2 is opaque, and therefore the light of the LEDs 4 only comes out through the transparent cover 5. It limits the angle of illumination.
The primary objective of the present invention is to provide an illuminating apparatus which has a good thermal dissipation performance.
The secondary objective of the present invention is to provide an illuminating apparatus which has a wide angle of illumination.
According to the objective of the present invention, the present invention provides an illuminating apparatus which includes a lamp member, a lighting member, a waterproof member, and cooling liquid. The lamp member has a closed chamber, in which the cooling liquid is filled. The lamp member has at least a metal heat sink in the chamber. The heat sink has at least a slot. The lighting member is received in the slot of the heat sink, and it has at least a substrate in touch with the heat sink and at least a light emitting diode on the substrate. The substrate has a conductor pattern on a side to which the light emitting diode is electrically connected. The waterproof member is received in the slot of the heat sink to embed the conductor pattern on the substrate therein. Insulation glue is filled in the slot and solidified to form the waterproof member.
With the thermal convection of the cooling liquid, it may dissipate the heat of the light emitting diode quickly to extend the product's life.
The detailed description and technical contents of the present invention will be explained with reference to the accompanying drawings. However, the drawings are illustrative only but not used to limit the present invention.
As shown in
The lamp member 10 has a cover 12, an insulating base 14, a metallic heat sink 16, and a conductive connector 18. The cover 12 is a transparent half-sphere plastic (such as acrylic) housing. The cover 12 is fixed to the base 14 to form a closed chamber 10a in the lamp member 10. The heat sink 16 is fixed to a top of the base 14. As shown in
The lighting member 20 is received in the slot 16a of the heat sink 16. The lighting member 20 has a substrate 22 and a plurality of LEDs 24.
In an embodiment, the substrate 22 is a MCPCB which has a conductor pattern 22a, an insulating plate 22b and a dissipating plate 22c. The conductor pattern 22a and the dissipating plate 22c are provided on opposite sides of the insulating plate 22b, and the dissipating plate 22c is attached to a bottom of the slot 16a of the heat sink 16 by soldering or thermal conductive adhesive. In order to obtain a good thermal dissipation performance, the dissipating plate 22c may be made of aluminum, copper, or other material which has a high heat transfer coefficient.
The LEDs 24 are electrically connected to the conductor pattern 22a of the substrate 22. The conductor pattern 22a is connected to an internal circuit (not shown) through waterproof wires 26, and the internal circuit is connected to the conductive connector 18 to supply the LEDs 24 with power. Each LED 24 has a light output face 24a.
The waterproof member 30 is formed by solidified insulation glue which is filled into the slot 16a. The waterproof member 30 embeds the entire conductor pattern 22a and other conductive portions, such as the connecting portions of the wires 26 and the conductor pattern 22a, therein.
In an embodiment, the cooling liquid 40 is deionized (DI) water, such as purified water, to be filled in the chamber 10a of the lamp member 10. The lighting member 20 is isolated from the cooling liquid 40 by the waterproof member 30, and therefore the LEDs 24 can work normally.
Because of the protection of the waterproof member 30, the cooling liquid 40 may serve the function of thermal dissipation without damaging the lighting member 20. Except the cooling liquid 40, the heat of the LEDs 24 is also transferred to the heat sink 16, which has a large area in touch with the lighting member 20.
With the thermal conduction of the heat sink 16 and the thermal convection of the cooling liquid 40, the heat may be transferred out of the apparatus 1 quickly. Furthermore, the plastic cover 12 has a high thermal radiation coefficient than metallic cover, so that it may dissipate the heat out of the apparatus 1 even more quickly. The design of the present invention is preferred to be applied in a high efficiency illuminating apparatus 100 which has a plurality of LEDs 24 in series-parallel connection, as shown in
The slot 16a of the heat sink 16 may receive the insulation glue therein to ensure covering all the conductive portions of the lighting member 20, including the conductor pattern 22a. Besides, the plastic cover may be mixed with metal particles according to the specific requirement. In the present invention, the heat sink 16 and the cooling liquid 40 are the two elements which serve the function of thermal dissipation so that the base 14 may be made of plastic to reduce the cost.
In an embodiment, the light output faces 24a of the LEDs 24 are uncovered by the waterproof member 30. In another embodiment, the light output faces 24a of the LEDs 24 are embedded in the waterproof member 30 therein (
In an embodiment, the walls 52 are made of metal, and they are inherently formed with the heat sink 50. In another embodiment, the walls 52 are made of plastic attached to the heat sink 50 by any known way. The plastic walls 52 may reduce the cost.
As shown in
The illuminating apparatus 300 has a lamp member 70, which includes a cover 72 and an insulating base 74. The cover 72a has a ball housing 72a and a tube 72b at an end of the ball housing 72a. The tube 72b is provided with a threaded section 72c at an inner side thereof. The insulating base 74 has a mounting portion 74a and a threaded connector 74b. The threaded connector 74b is meshed with the threaded section 72c of the cover 72 to form a chamber 70a in the lamp member 70, in which the cooling liquid 40 is filled. Four heat sinks 76 are vertically mounted on the mounting portion 74a of the insulating base 74 to form a rectangular pillar. Therefore, the heat sinks 76 are received in the ball housing 72a and are closer to its inner side than the first preferred embodiment. Each heat sink 76 is provided with an elongated slot 76a.
A lighting member 80 has a plurality of substrates 82 and a plurality of LEDs 84 on each substrate 82. The substrates 82, which are MCPCB in the embodiment, are respectively received in the slots 76a of the heat sinks 76. The function of the substrates 82 and the LEDs 84 are the same as described above, so we do not describe the detail again. Because that the heat sinks 76 are arranged in an annular pattern and the LEDs 84 are lined in a vertical direction, the LEDs 84 may emit light in all directions out of the ball housing 72a. Therefore, illuminating apparatus 300 has a good thermal dissipation and a wide angle of illumination.
The substrate of the light member is required to have a good electrical insulation and a high heat transfer coefficient, so that the substrate may be, except for the MCPCB as described above, thick film ceramic substrate, and direct bonded copper (DBC) substrate is more preferable. Of course, the thick film ceramic substrate has the same elements, such as the conductor pattern, as described above.
The illuminating apparatus of the present invention may be incorporated in street lamp, recessed lamp, projection lamp, headlamp, flashlight, and other equivalent devices.
The description above is a few preferred embodiments of the present invention, and the equivalence of the present invention is still in the scope of claim construction of the present invention.
