Patent ID: 8347951

Claim:
A heat dissipation device for dissipating heat from a heat-generating electronic element, the device comprising: a canister filled with a phase-changeable working fluid and adapted for receiving heat from the heat-generating electronic component; a housing hermetically fixed to a top of the canister and communicating with the canister; a fan located on a top of the housing, the fan comprising a hub having an opening facing the housing, a plurality of blades extending outwardly from a circumference of the hub and a plurality of windings fixed on an inner side of the hub; and an impeller comprising a driving member received in the housing, an annular magnet accommodated in the hub of the fan and surrounded by the windings and an axle coaxially connecting the driving member and the annular magnet together, wherein when the driving member rotates the annular magnet rotates accordingly; wherein the axle comprises a lower end extending downwardly through a bottom of the housing to a center of the top of the canister and an upper end extending upwardly through a top of the housing to be received in the fan and wherein when the working fluid is heated by the heat-generating electronic element and vaporized to move into the housing and through the driving member, the driving member is driven by the vaporized working fluid to rotate, whereby the annular magnet is rotated within the windings and the windings are induced by the rotating annular magnet to generate a current therein.