Cooling technology of LED lamp heads such as flashlights

- May 17, 2016-

Most of today's society's lighting products use LED lights, which are already indispensable lighting tools in my life. However, due to the long continuous use time, the temperature of the lamp body is very high. If the heat is not well cooled, this will greatly reduce the service life of the LED. The outer casing of a good LED lamp has a good heat dissipation function. However, depending on the application, the LED lamp housing has different processes.

The most common way to dissipate heat is to use aluminum fins as part of the enclosure to increase the heat sink area. Another is to fill the heat-conducting material when the plastic shell is injection-molded, and increase the heat-conducting and heat-dissipating ability of Or use the surface of the lamp housing for radiation heat dissipation. Simply apply the radiation heat-dissipating paint, and the heat can be radiated from the surface of the lamp housing with the radiation of the LED street lamp housing. Or use the shape of the lamp housing to create convective air, which is the lowest cost way to enhance heat dissipation. Or the inside of the lamp housing uses a long-life and high-efficiency fan to enhance heat dissipation, which is low in cost and good in effect. However, it is more troublesome to change the fan, and it is not suitable for outdoor use. This design is rare. Or use heat pipe technology to conduct heat from the LED chip to the heat sink fins of the case. This is a more common design. Or use liquid bubble encapsulation technology to fill a transparent liquid with a high thermal conductivity into the bulb of the lamp body. This is the only technology that uses the light-emitting surface of the LED chip to conduct heat and dissipate heat in addition to the principle of reflection. Or a household-type, smaller-power LED lamp often uses the internal space of the lamp cap to partially or completely insert the LED street lamp housing drive circuit. This makes it possible to dissipate heat from a lamp head having a large metal surface such as a screw cap because the lamp cap is in close contact with the metal electrode of the lamp holder and the power cord. Therefore, a part of the heat can be derived from heat dissipation. Or the purpose of heat dissipation of the lamp housing is to reduce the operating temperature of the LED chip. Since the expansion coefficient of the LED chip is very different from the commonly used metal heat conduction and heat dissipation material expansion coefficient, the LED chip cannot be directly soldered to avoid high and low temperature thermal stress damage to the LED chip. . The latest high thermal conductivity ceramic material, the thermal conductivity is close to aluminum, and the expansion system can be adjusted to synchronize with the LED chip. In this way, heat conduction and heat dissipation can be integrated to reduce the intermediate part of heat conduction.