MANUFACTURING METHOD OF LAMP HOUSING TYPE HEAT-SINK, LAMP HOUSING TYPE HEAT-SINK AND LED LIGHTING DEVICE

摘要

A lamp housing type heat-sink (2) in an LED lighting device, made monolithically by extending a high purity aluminium plate having a thickness of 0.5 mm to 5 mm and an aluminium content of above 95%, to form a hollow middle part. The lamp housing type heat-sink consists of a heat-sinking surface (21) and a housing body (22), wherein a surface contact structure is formed between the heat-sinking surface and a circuit board (3), and heat-sinking through-holes able to form heat-sinking channels are provided on the housing body. The method of manufacturing the lamp housing type heat-sink in the LED lighting device consists in making the heat-sink monolithically by extending a high purity aluminium plate having a thickness of 0.5 mm to 5 mm and an aluminium content of above 95%. As the thermal conductivity co-efficient of the extending aluminium is 230W/(m·K) and the thermal conductivity coefficient of die casting aluminium is less than 100W/(m·K), it is necessary to use only 1/3 to 1/5 of the material of a die casting aluminium housing to achieve either the same result as die casting aluminium or a better heat-sinking result, and at the same time the cost is only a half to one third of that of a die casting aluminium housing. The material used of extended aluminium plate is also reduced, lowering the cost.