Patent ID: 7255154

Claim:
A cooling device comprising: a heat-radiating device and a centrifugal pump provided in a closed circulation passage for circulating refrigerant, wherein the centrifugal pump contacts heat-generating electronic parts to absorb heat from the heat-generating electronic parts by the heat exchange of the refrigerant therein to radiate the heat via the heat-radiating device, wherein the centrifugal pump includes: a lower casing that comes into contact with the heatgenerating electronic parts; an upper casing disposed to face the lower casing to form a pump chamber; and an impeller sandwiched between the upper casing and the lower casing, wherein the lower casing includes a recessed conical surface facing the impeller, a plurality of protrusions provided in a center portion of the recessed conical surface and a contact face with which the heat-generating electronic parts come into contact formed directly below the protrusions on an opposite side of the recessed conical surface, and wherein at least one of the protrusions supports a bearing of the impeller.