Cooling device

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 comes into contact with heat-generating electronic parts to absorb heat from the heat-generating electronic parts by the heat exchange of the refrigerant to radiate the heat via the heat-radiating device,
• wherein the centrifugal pump includes:
• a first casing having a heat-receiving surface that comes into contact with the heat-generating electronic parts and receives heat;
• a second casing fitted with the first casing and sandwiches an impeller between the first casing and the second casing;
• and
• a sealing member sandwiched between the first casing and the second casing to form a pump chamber, and
• wherein a recessed conical surface is formed on the side of the first casing facing the impeller.

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 heat-generating 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, and
• 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 are formed so as to protrude toward the impeller with heights of the protrusions decreasing radially outward, and a contact face with which the heat-generating electronic parts come into contact formed directly below the protrusion on an opposite side of the recessed conical surface.