CN101852358A

CN101852358A - LED lamp

Info

Publication number: CN101852358A
Application number: CN201010209049A
Authority: CN
Inventors: 任立宏; 谢中; 蒋文科; 陈小林; 王祝盈; 任长学
Original assignee: HUNAN YOULI MEDICAL TECHNOLOGY Co Ltd
Current assignee: HUNAN YOULI MEDICAL TECHNOLOGY Co Ltd
Priority date: 2010-06-25
Filing date: 2010-06-25
Publication date: 2010-10-06

Abstract

The invention discloses an LED (light-emitting diode) lamp comprising an LED light-source board provided with a metal base board, and a radiator assembly composed of a cup-shaped heat pipe and an aluminum radiator, wherein the bottom surface of the cup-shaped heat pipe is tightly fitted with the LED light-source board by screws; the lower end of the radiator is connected with a lamp shade via threads or bayonets, and the upper end thereof is connected with a lamp holder; and the inner part of a lamp bulb is completely sealed. Accordingly, the invention not only ensures the good sealing performance and safety performance, but also achieves the good effect of heat dissipation, particularly, the LED lamp is capable of effectively dissipating the heat generated by the LED bulb into the environment; and the LED lamp of the invention has the significant advantages of light weight, super-high heat dissipation capacity and better base board temperature uniformity. Therefore, the LED lamp is applicable as an LED illuminating lamp above 5 watts.

Description

A kind of LED lamp

Technical field

The present invention relates to a kind of LED lamp.

Background technology

The right crucial difficult problem of LED illuminated area is heat radiation.For white light,, approximate 300 lumens if one watt electrical power is converted into light fully.The light efficiency of at present best commercial LED white chip is about 100lm/W, this means the electrical power that is added on the White-light LED chip, has nearly 70% to change into Joule heat.For single led, if concentrating in the small-sized chip, heat can not effectively shed, can cause chip temperature to raise, the non-uniform Distribution, chip light emitting efficient and the fluorescent material that cause thermal stress swash penetrates decrease in efficiency, causes producing serious light decay or dead lamp.Along with the temperature rising of PN junction, red shift also will take place in the emission wavelength of white light LED part.Research data shows: under 100 ℃ temperature, wavelength can red shift 4～9nm, thereby causes YAG fluorescent material absorptivity to descend, and total luminous intensity reduces, white light colourity variation.Near room temperature, 1 ℃ of the every rising of temperature, the luminous intensity of LED can correspondingly reduce about 1%.When a plurality of LED dense arrangement were formed white lumination system, the dissipation problem of chip heat was more serious under the airtight situation.Therefore resolve heat dissipation problem and become the prerequisite that the LED illumination is used.In order to guarantee the life-span of device, generally require junction temperature below 100 ℃.Studies show that: when temperature surpasses 100 ℃, it is soaring that the crash rate of device will be index law, 2 ℃ of the every risings of component temperature, reliability decrease 10%.So it is significant to LED to dispel the heat.LED lamp with 10W is an example, lights the LED lamp of a 10W, will produce the Joule heat about 7W.If these heats can not dissipate effectively, will produce the fatal influence of two aspects: reduce the luminous efficiency of LED lamp, shorten the service life of chip even damage the lamp pearl to whole bulb.Because the working life of LED presents exponential reduction with the temperature increase, so, the heat that produces during with LED lamp burning-point is dispersed in the surrounding environment effectively, reduces the operating temperature of chip as far as possible, is the key that improves LED illuminating lamp functional reliability, prolongs the LED lamp life-span.

The method that the heat radiation of existing small power LED lamp is generally adopted both at home and abroad is that the heat that produces during with the LED burning-point by aluminum base PCB plate and high-ratio surface aluminium radiator is transmitted to the heat dissipation problem that solves LED on the radiator.Because the high mass density and the price of metal_based material make that the bulb monomer is heavier, cost is difficult to reduce; Owing to the limited thermal conductivity of metal, heat-sinking capability is often not enough on the other hand, influences light efficiency, life-span and the reliability of device.

Summary of the invention

In order to solve the above-mentioned technical problem that the heat radiation of LED lamp exists, the invention provides a kind of LED bulb.

The technical scheme that the present invention solves the problems of the technologies described above is: comprise lamp holder, power driving circuit, the led light source plate of band metal substrate, radiator, the led light source plate of band metal substrate is fixed on the radiator, described radiator inner surface surrounds a cavity with heat pipe, is perfused with working medium in the heat pipe.

In the above-mentioned LED lamp, described heat pipe is cup-shaped, and the led light source plate of band metal substrate is fixed in the heat pipe bottom surface.

In the above-mentioned LED lamp, the upper end of described radiator links to each other with lamp holder, and the lower end links to each other with lampshade by screw thread or bayonet socket.

In the above-mentioned LED lamp, being seated in the cavity that heat pipe surrounds of described power driving circuit.

Technique effect of the present invention is: the present invention has so just reduced the thermal contact resistance of LED lamp and radiator greatly with the bottom surface of the heat pipe installation base plate as the LED lamp, has improved radiating effect.The present invention is when keeping high heat transfer efficient, also provide the space for the driving power plate, make that bulb has more compact structure, weight is lighter, cost is lower, substrate temperature is lower, the better outstanding advantage of temperature homogeneity, easilier satisfy 3-20W even the more heat radiation requirement of high-capacity LED bulb, a kind of radiator structure of excellence is provided for long-life middle low power LED bulb, can break through the heat radiation bottleneck that the LED bulb is used at one stroke, significantly promote the general power level of LED lighting bulb, expand its range of application.

The present invention is further illustrated below in conjunction with accompanying drawing.

Description of drawings

Fig. 1 overall structure figure of the present invention.

Fig. 2 is the A-A cutaway view of Fig. 1.

Fig. 3 is the cutaway view of cup-shaped heat pipe among the present invention.

Fig. 4 is the cutaway view of cylindrical shape heat pipe among the present invention.

1 to be heat pipe section 2 be transparent outer cover 7 built-in driving power plates for radiator 5 for lamp holder 6 for the bottom 4 of cup-shaped heat pipe for the cavity in the cup-shaped heat pipe 3 among the figure.

The specific embodiment

Referring to Fig. 1,2, Fig. 1,2 is the structure chart among the present invention.The present invention includes the cavity that lamp holder 1, radiator 2, heat pipe 5, lampshade 3,4 surround for heat pipe 5.Cavity 4 can be used to lay the driving power plate, and driving power plate institute caloric value also can be distributed preferably.Heat pipe 5 in the present embodiment is cup-shaped, its structure is seen Fig. 3,51 is heat pipe outer wall among the figure, 53 is the heat pipe inwall, and 52 is heat pipe inner chamber, and 54 is the chimb of heat pipe base plate, be convenient to the fixing and close contact of heat pipe and radiator 2, be marked with working medium in the heat pipe inner chamber 52, the outer tube welding production of general available copper coin in the bottom of cup-shaped heat pipe 5 and cup-shaped heat pipe, but also punching press one-shot forming.When described cup-shaped heat pipe 5 was the antigravity type, the inner face and the internal face of the outer cup of cup-shaped heat pipe were capillary structure, and this capillary structure can be capillary, dovetail groove or copper mesh form.The bottom surface 6 of cup-shaped heat pipe 5 contacts with aluminium base led circuit plate, and fix with screw, contact-making surface is smeared heat-conducting silicone grease, and the bottom surface 6 of heat-conducting silicone grease and trip bolt make aluminium base (or copper base or other good thermal conductor substrates) led circuit plate and heat pipe 5 keeps good thermo-contact.And it is possible to prevent that (or copper base or other good thermal conductor substrates) led circuit plate aluminium base after the repeated multiple times thermal cycle and cup-shaped heat pipe end from coming off.Cup-shaped heat pipe 5 embeds in the aluminium radiator with interference fits, links to each other with the cast aluminium radiator by screw thread at radiator lower end transparent lamp shade 3.

Referring to Fig. 4, the structure of heat pipe and Fig. 3 are different among Fig. 4, and heat pipe 5 is columnar structured.Heat pipe 5 also can adopt the cup type structure of multiaspect shape of upper end open or polygon prism structure etc.

Among the present invention, when cup-shaped heat pipe heating end face down, when the LED lamp is lighted, cup-shaped heat pipe outer tube end face is heated, heat pipe starts, liquid refrigerant flashes to the crack of gaseous state by inner and outer pipe and shifts heat release fast to the low top of temperature, flow back to cup-shaped heat pipe bottom end face after being condensed into liquid, whole heat pipe has only the very little temperature difference, the approaching temperature state that waits.Because cup-shaped heat pipe and radiator are by the interference fits crimping, thermal resistance between radiator and cup-shaped heat pipe is very little, the temperature difference of radiator root and cup-shaped heat pipe is also very little, the heat that this phase-change working substance heat transfer type can produce the heating of LED lamp effectively is delivered on the radiator equably, and can regulate the heat that is transported to the radiator each several part automatically, make cooling system be always operating at best radiating state.Because the thermal resistance of cup-shaped heat pipe is little, do not have on the absorber plate of end that conventional heat dissipating method produces by the thermograde of substrate center to the edge, can guarantee that each LEDs chip all works in the temperature range of safety.

When the heat pipe heating end faced up, because capillarity, liquid working substance was transported on the end face that is heated by the capillary channel in capillary structure in the cup-shaped heat pipe and tube wall gap, as mentioned above, finished the heat conduction circulation.

Claims

1. LED lamp, comprise lamp holder, power driving circuit, the led light source plate of band metal substrate, radiator, the led light source plate of band metal substrate is fixed on the radiator, and it is characterized in that: described radiator inner surface surrounds a cavity with heat pipe, is perfused with working medium in the heat pipe.

2. LED lamp according to claim 1 is characterized in that: described heat pipe is cup-shaped, and the led light source plate of band metal substrate is fixed in the heat pipe bottom surface.

3. LED lamp according to claim 1 is characterized in that: any of cup type structure of described multiaspect shape or polygon prism structure, the led light source plate of band metal substrate is fixed in the heat pipe bottom surface.

4. according to claim 2 or 3 described LED lamps, it is characterized in that: smear Heat Conduction Material between described heat pipe bottom surface and the metal substrate, and fastening contact.

5. LED lamp according to claim 1 is characterized in that: described heat pipe outer wall embeds in the radiator.

6. LED lamp according to claim 5 is characterized in that: smear Heat Conduction Material between described heat pipe and the radiator contact-making surface, and close contact.

7. LED lamp according to claim 1 is characterized in that: the upper end of radiator links to each other with lamp holder, and the lower end links to each other with lampshade by screw thread or bayonet socket.

8. LED lamp according to claim 1 is characterized in that: being seated in the cavity that heat pipe surrounds of described power driving circuit.

9. LED lamp according to claim 1 is characterized in that: described cup-shaped heat pipe is gravity-type heat pipe or antigravity type.

10. LED lamp according to claim 1 is characterized in that: when described cup-shaped heat pipe was the antigravity type, the inner face and the internal face of the outer cup of cup-shaped heat pipe were capillary structure, and this capillary structure can be capillary, dovetail groove or copper mesh form.