Abstract: A cooling device includes an upper flat plate-shaped member and a lower flat plate-shaped member disposed with a predetermined interval therebetween, a heat radiation fin configured to extend from the upper flat plate-shaped member toward the lower flat plate-shaped member and to form a flow path through which air flows between the upper flat plate-shaped member and the lower flat plate-shaped member, and a centrifugal fan having an inlet as an opening and an outlet configured to be open in a direction intersecting an opening direction of the inlet, wherein the centrifugal fan is disposed at a position separated from the upper flat plate-shaped member by a predetermined interval so that the outlet is open toward the flow path, and a protruding part that protrudes toward the centrifugal fan is provided on the upper flat plate-shaped member.

Abstract: A heatsink is used with a fluid flow generator that rotates about a central axis extending vertically. The heatsink includes a main body section having a top surface facing the fluid flow generator in a vertical direction, and fins that extend upward from the top surface so as to define a plurality of flow passages. The plurality of flow passages form a plurality of fluid paths, each of which has an inlet for the fluid discharged from the fluid flow generator to flow in, and an outlet for discharging to outside the fluid that has entered through the inlet. At least one of the plurality of fluid paths has a first branch section for branching from a first fluid path on downstream of the inlet, and a first joining section for joining a second fluid path having another inlet, on downstream of the first branch section.

Abstract: A heatsink, which is used with a fluid flow generator that rotates about a central axis extending vertically to generate a flow of fluid, includes a main body section having a top surface facing the fluid flow generator in a vertical direction, and fins that extend upward from the top surface so as to define a plurality of flow passages. Four regions defined by an X axis and a Y axis, which cross each other at an intersection between the central axis and the top surface and extend in an extending direction of the top surface, are referred to as a first region, a second region, a third region, and a fourth region, in order in a direction opposite to a rotation direction of the fluid flow generator.