CN100504157C - LED lamp with active heat-transfer and cooling functions - Google Patents

Abstract

A semiconductor lighting fixture using active cooling comprises a heat dissipation cover, an active heat transfer and cooling device and a light emitting diode module; the active heat transfer and cooling device is arranged in the heat dissipation cover, and comprises an evaporator, a condenser, a compressor, an expansion valve and a cryostat, wherein the cryostat is arranged on the evaporator, the condenser is arranged on the heat dissipation cover, the compressor, the condenser, the expansion valve and the evaporator are interconnected to form a closed loop, and a refrigerant is arranged in the loop; the light emitting diode module is in contact with the cryostat and comprises at least one light emitting diode; the light emitting diode is subjected to heat absorption and cooling by the low temperature refrigerant, so that the temperature of the light emitting diode can be reduced, the life of the light emitting diode can be extended and the brightness of the light emitting diode can be improved.

Description

Light-emitting diode lamps with active heat removal and cooling functions

technical field

The invention relates to a light-emitting diode device, in particular to a light-emitting diode that uses low-temperature refrigerant in a compression cycle to absorb heat and cool down.

Background technique

Light emitting diodes (Light Emitting Diode, LED) have the effect of saving energy and energy, and have been rapidly popularized recently. They are often used in electronic equipment such as traffic lights, electronic signage, flashlights, desk lamps, and projection lights. However, light-emitting diodes generate high heat during operation. If the light-emitting diodes are not equipped with a proper heat dissipation design, the lifespan of the light-emitting diodes will be greatly shortened or even burned due to high temperature during operation.

Generally speaking, the core temperature of LEDs can be tolerated at 120 degrees Celsius, which is much lower than the operating temperature of traditional light bulbs. The heat dissipation design of high-brightness LED devices will deeply affect their service life.

In addition, the luminous brightness of LEDs is related to the die temperature. As shown in Table 1 below, effectively reducing the die temperature can significantly improve the brightness of LEDs. For example, when the die temperature is lowered from the general design value of 90 degrees Celsius to 25 degrees Celsius Its brightness can be increased by 33% at high temperature.

Table 1. Relationship between crystal core temperature (Ti) and luminous brightness of light-emitting diodes

LED T_j℃ Relative intensity Intensity increase from T_j＝90℃ 90 75 Baseline 60 87 +16% 50 91 +21% 45 93 +24% 40 95 +27% 25 100 +33%

In addition, reducing the temperature of the core can also prolong the service life. For example, under a constant current, the temperature of the base where the light-emitting diode is located (the temperature of the core is about 101 degrees Celsius) drops from 85 degrees Celsius to 55 degrees Celsius (the temperature of the core is about 81 degrees Celsius). degree), the LED lifetime (defined as light decay of 0.7) can be increased from 15,000 hours to 60,000 hours, which is four times longer than the original lifetime.

Apparently, lowering the temperature of the core of the light-emitting diode helps improve the brightness and life of the light-emitting diode, but to reduce the temperature of the light-emitting diode, it must start with its heat dissipation.

For a 50-100 watt high-power LED lighting fixture, it is extremely difficult to make an effective heat dissipation design in the narrow interior space of the lighting fixture.

The traditional aluminum or copper heat sink with fan cooling design is not only bulky, but also makes noise when the fan is running, so it is not suitable for LED devices.

Please refer to FIG. 4 , there is another design for heat dissipation of LEDs with loop heat pipes. A heat conduction base 90 is mainly arranged inside a heat dissipation cover 93 , and several light emitting diodes 91 are arranged outside, and a loop heat pipe is arranged on the heat conduction base 90 ( Loop Heat Pipe, LHP) 92, the loop heat pipe 92 is wound on the heat dissipation cover 93, and the interior is provided with a volatile liquid, whereby the loop heat pipe 92 can absorb the high heat of the light-emitting diode 91 with the internal liquid, and exchange heat with the outside As for heat dissipation, although this design can effectively dissipate heat to the LED 91, when the heating power of the LED 91 exceeds 150 watts, or the size of the LED lamp increases, the performance of the loop heat pipe 92 is insufficient, or the performance is greatly reduced.

In addition, the heat dissipation structure mentioned above is a passive heat dissipation design, that is, it only relies on the temperature difference between the high temperature of the light-emitting diode and the normal temperature during operation to dissipate heat. This heat dissipation method is easily affected by the ambient temperature and the degree of ventilation in the environment. .

Contents of the invention

Therefore, based on the shortcomings of the existing Light Emitting Diode (LED) devices that only use passive heat dissipation designs with low efficiency to dissipate heat, the inventors improved their deficiencies and deficiencies, and then created an active heat transfer device for LED lamps with cooling device.

The problem to be solved by the present invention is to provide an LED lamp with active heat removal and cooling functions, which uses the low-temperature refrigerant in the compressor cycle to absorb heat and cool down the LED.

In order to solve the above problems, the LED lamp with active heat transfer and cooling functions of the present invention includes:

cooling cover;

The active heat transfer and cooling device is set in the heat dissipation cover, and includes an evaporator, a condenser, a compressor, an expansion valve and a cryopanel, wherein the cryopanel is set on the evaporator, and the condenser is set in the heat dissipation cover Above, the compressor, condenser, expansion valve and evaporator are connected to each other, and the connection sequence is that the compressor is connected to the condenser, the condenser is connected to the expansion valve, the expansion valve is connected to the evaporator, and the evaporator is connected to the compressor to form a closed loop. There is a refrigerant, the compressor can compress the gaseous refrigerant, and the expansion valve can expand the refrigerant; and

The light emitting diode module is arranged on the cryopanel to be in contact with the cryopanel, and includes at least one light emitting diode.

The aforementioned condenser is arranged on the heat dissipation outer cover.

The aforementioned cryopanel is composed of two plates fixed to each other, one of which is a heat conduction plate, and the other is a heat preservation plate, and the evaporator is sandwiched between the two plates.

The aforementioned light-emitting diode module includes a base, an inner chamber is formed on the side of the base in contact with the cryopanel, and several perforations that communicate with the inner chamber and pass through the base are formed on the base. The reflective material is provided with a circuit board in the content chamber, and the light-emitting diodes are arranged on the circuit board and protrude into corresponding through holes.

The sections of the aforementioned perforations form a trapezoid, and the wider end of the trapezoid faces away from the cryopanel.

A gas chamber connected to the perforation is formed on the side of the base facing away from the cryopanel. The gas chamber is filled with low dew point gas, and the base is provided with an outer transparent plate that seals and covers the gas chamber. The low dew point gas It can avoid frost or condensation on the surface of the transparent plate at low temperature, so as to block the light from emitting.

At least one hot gas bypass pipe is formed on the aforementioned base to heat the transparent plate to avoid frost or condensation on the surface of the transparent plate at low temperature, so as to block light from emitting.

The above-mentioned base is composed of a heat insulation board arranged on the cryogenic board, an inner base arranged on the heat insulation board and an outer base arranged on the inner base to fix each other.

The bottom of the gas chamber of the base is provided with an inner transparent plate between the inner base and the outer base, and the inner transparent plate covers the through hole of the base and the light emitting diode.

The aforementioned low dew point gas is interposed between the inner transparent plate and the outer transparent plate.

The aforementioned hot gas bypass pipe is formed on the outer base adjacent to the transparent plate.

The aforementioned low dew point gas is nitrogen.

The aforementioned transparent plate is made of glass.

The aforementioned transparent plate is made of plastic.

The aforementioned heat dissipation cover is made of metal.

Compared with prior art, the beneficial effect of the present invention is:

With the above-mentioned technical means, the heat generated by the light-emitting diodes is transferred to the liquid refrigerant in the evaporator through the cryogenic plate. After heat dissipation by the condenser, it condenses into a high-pressure and high-temperature liquid refrigerant, and through the expansion valve, it becomes a gas-liquid mixed refrigerant with low pressure and temperature lower than the ambient temperature. Finally, the refrigerant enters the evaporator to complete a compression cycle, using the low-temperature refrigerant in the compression cycle. The light-emitting diodes absorb heat and cool down, which can reduce the impact of ambient temperature changes and poor ventilation on the light-emitting diodes, and even maintain the temperature of the light-emitting diodes below the ambient temperature. By reducing the temperature of the light-emitting diodes, the life of the light-emitting diodes can be extended and Increase the brightness of LEDs.

Description of drawings

Fig. 1 is a side partial sectional view of the present invention;

Fig. 2 is the perspective view of the present invention;

Figure 3 is an enlarged side sectional view of the present invention;

Fig. 4 is a side sectional view of an old light-emitting diode lamp.

[Description of main component symbols]

10: Heat dissipation cover 20: LED module

21: Base 211: Heat shield

212: inner base 213: outer base

214: Content Room 215: Perforation

216: Gas chamber 217: Hot gas bypass pipe

218: Gasket 219: High reflective material

22: Outer transparent board 23: Inner transparent board

24: Circuit board 25: LED

26: Gasket 27: Gasket

30: Evaporator 40: Condenser

50: Compressor 60: Expansion valve

70: cryogenic plate 71: heat conduction plate body

72: Insulation board body 80: Refrigerant

90: Thermal base 91: Light emitting diode

92: Loop Heat Pipe 93: Heat Dissipation Cover

Detailed ways

Please refer to FIGS. 1 and 2 , the LED lamp with active heat transfer and cooling function of the present invention includes: a heat dissipation cover 10 , an active heat transfer and cooling device, and a light emitting diode (Light Emitting Diode, LED) module 20 .

Please refer to FIG. 3 further. The active heat transfer and cooling device is disposed in the heat dissipation housing 10 and includes a cryopanel 70 , an evaporator 30 , a condenser 40 , a compressor 50 and an expansion valve 60 .

The cryopanel 70 is arranged in the heat dissipation outer cover 10 and is composed of two plates, one of which is a heat conducting plate 71 made of high thermal conductivity materials such as metal, and the other plate is made of Styrofoam, etc. The insulation board body 72 made of low thermal conductivity material.

The evaporator 30 is interposed between the heat conduction plate 71 and the heat preservation plate 72 .

The condenser 40 is disposed on the heat dissipation cover 10 , and by being in contact with the heat dissipation cover 10 , the heat on the condenser 40 can be dissipated by utilizing the large surface area of the heat dissipation cover 10 .

The above-mentioned compressor 50, condenser 40, expansion valve 60 and evaporator 30 are connected to each other, and the connection sequence is that the compressor 50 is connected to the condenser 40, the condenser 40 is connected to the expansion valve 60, the expansion valve 60 is connected to the evaporator 30, and the evaporator 30 is connected to The compressor 50 constitutes a closed circuit, and a refrigerant 80 is arranged in the circuit. The compressor 40 can compress the gaseous refrigerant 80 , and the expansion valve 60 can expand the refrigerant 80 .

The light-emitting diode module 20 is arranged on the active heat transfer and cooling device and is in contact with the heat conduction plate body 71 of the cryopanel 70, and includes a base 21, an outer transparent plate 22, an inner transparent plate 23, low dew point gas, and a circuit board 24 , at least one LED 25 and two gaskets 26 and 27 .

The base 21 is arranged on the cryopanel 70 and includes a thermal insulation board 211, an inner base 212, an outer base 213, an inner chamber 214, at least one perforation 215, a gas chamber 216, at least a hot gas bypass pipe 217, and a gasket 218 and at least one highly reflective material 219; the heat shield 211 is ring-shaped and arranged on the heat conduction plate body 71 of the cryopanel 70; the inner base 212 is arranged on the heat shield 211; the outer base 213 is arranged On the inner base 212; the inner chamber 214 is formed on the side of the base 21 facing the cryopanel 70, and is located between the inner base 212 and the heat shield 211; the perforation 215 is formed through the inner base 212 And communicate with the inner chamber 214, the perforation 215 cross-section is a trapezoid, the trapezoid has a wide end and a narrow end, the wide end faces away from the cryopanel 70; the high reflection material 219 is arranged on the inner wall of the perforation 215; the gas chamber 216 is formed outside On the base 213 and adjacent to the perforation 215; the hot gas bypass pipe 217 is annularly formed on the outer base 213 to heat the transparent plate to avoid frosting or condensation in the gas chamber 216 at low temperature, preventing The light is emitted; the gasket 218 is disposed between the inner base 212 and the outer base 213 .

The outer transparent plate 22 can be made of glass or plastic, and is arranged on the base 21 to seal and cover the gas chamber 216 .

The inner transparent plate 23 can be made of glass or plastic, and is disposed at the bottom of the gas chamber 216 of the base 21 , between the inner base 212 and the outer base 213 , and covers the through hole 215 . By passing hot air into the inside of the hot air bypass pipe 217, frost or condensation on the surfaces of the inner/outer transparent plates 22, 23 can be removed.

The low dew point gas can be nitrogen gas, which is arranged in the gas chamber 216 of the base 21 and between the outer transparent plate 22 and the inner transparent plate 23. The low dew point gas can avoid frosting or condensation on the transparent plate 22, 23 so as to block light from exiting.

The circuit board 24 is disposed in the inner chamber 214 of the base 21 .

The light emitting diode 25 is disposed on the circuit board 24 and extends into the corresponding through hole 215 of the base 21 . With the trapezoidal cross section of the through hole 215 and the highly reflective material 219 , the light emitted by the light emitting diode 25 can be concentrated and emitted.

The gasket 26 is arranged between the circuit board 24 and the heat insulation board 211 of the base 21 , and the other gasket 27 is arranged between the circuit board 24 and the cryopanel 30 .

With the above-mentioned technical means, the heat generated by the light-emitting diode 25 is transferred to the liquid refrigerant 80 in the evaporator 30 through the cryopanel 70, and the liquid refrigerant 80 evaporates into a gaseous state after absorbing heat and enters the compressor 50, and is compressed by the compressor 50 to become High-temperature and high-pressure gas, the gaseous refrigerant 80 is condensed into a high-pressure and high-temperature liquid refrigerant 80 through the condenser 40 for heat dissipation, and then passes through the expansion valve 60 to become a low-pressure gas-liquid mixed refrigerant 80 whose temperature is lower than the ambient temperature, and finally the refrigerant 80 enters the evaporator 30 Complete a compression cycle, use the compressor 50 and the low-temperature refrigerant 80 to absorb heat and cool down the light-emitting diode 25, which can reduce the impact of ambient temperature changes and poor ventilation on the light-emitting diode, and even maintain the temperature of the light-emitting diode 25 below Below the ambient temperature, and by reducing the temperature of the LED 25, the service life of the LED 25 can be extended and the brightness of the LED 25 can be increased.

Claims (7)

1. the led lamp of a tool active heat transfer and cooling function comprises:

The heat radiation outer cover;

The active heat transfer device, be arranged in the heat radiation outer cover, and include evaporimeter, condenser, compressor, expansion valve and cryopanel, wherein this cryopanel is arranged on this evaporimeter, this condenser is arranged on the heat radiation outer cover, compressor, condenser, expansion valve and evaporimeter interconnect, the order of connection is that compressor engages condenser, condenser engages expansion valve, expansion valve joint evaporimeter, evaporimeter joint compressor, constitute loop, be provided with refrigerant in the loop, the compressible gaseous coolant of compressor, the inflatable refrigerant of expansion valve; And

Light-emitting diode (LED) module is arranged on the cryopanel and contacts with cryopanel, and includes at least one light emitting diode;

Condenser is around being arranged on the heat radiation outer cover;

Cryopanel is interfixed by two plate bodys and forms, and wherein a plate body is the heat conduction plate body, and another plate body is the insulation plate body, and the heat conduction plate body contacts with light-emitting diode (LED) module, and this evaporimeter is located between two plate bodys, and this heat radiation outer cover is the metal manufacturing.

2. the led lamp of tool active heat transfer as claimed in claim 1 and cooling function, wherein light-emitting diode (LED) module includes pedestal, this pedestal is the thermal insulation board that is arranged on the cryopanel by, one be arranged on interior pedestal and on the thermal insulation board be arranged in outer frame on the pedestal composition that interfixes, on pedestal and one side that cryopanel contacts, be formed with interior room, on pedestal, be formed with the perforation that at least one is connected with interior room and runs through the interior pedestal of pedestal, and on the perforation inwall, be provided with high reflecting material, at the indoor circuit board that is provided with of content, light emitting diode is arranged on this circuit board and stretches into corresponding perforation.

3. the led lamp of tool active heat transfer as claimed in claim 2 and cooling function, it is one trapezoidal that the section of wherein respectively boring a hole becomes, and trapezoidal have a wealthy end and a narrow end, and wealthy end is back to cryopanel.

4. the led lamp of tool active heat transfer as claimed in claim 3 and cooling function, wherein pedestal is formed with the gas room adjacent with perforation on the one side of cryopanel, in the gas room, be filled with low dew point gas, be provided with the outer transparent panel of sealing blanketing gas room in pedestal.

5. the led lamp of tool active heat transfer as claimed in claim 4 and cooling function, wherein run through on the outer frame of pedestal and be formed with at least one hot-gas bypass pipe, in order to the heating transparent panel, frosting or condensation stop that light penetrates when avoiding low temperature on the surface of transparent panel.

6. the led lamp of tool active heat transfer as claimed in claim 5 and cooling function, wherein the gas room of pedestal bottom is provided with the interior transparent panel between interior pedestal and outer frame, should cover pedestal perforation and light emitting diode by interior transparent panel, should low dew point gas between interior transparent panel and outside between the transparent panel, frosting or condensation are on the surface of transparent panel in the time of can avoiding low temperature, penetrate so that stop light, and this low temperature dew point gas is nitrogen.

7. the led lamp of tool active heat transfer as claimed in claim 6 and cooling function, wherein transparent panel is with wherein a kind of manufacturing of glass and plastics.

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