Patent ID: 7522422

Claim:
A heat sink mounted on a heat radiation part through the medium of a coolant, comprising: a base member; a heat sink body formed in a frame shape having an outer frame surrounding an inner frame, the outer frame having a greater height (T) than a height (T 1 ) of the inner frame, said heat radiation page being receivable inside the outer frame and on top of the inner frame of said heat sink body, said heat body superposed on said base member to form in cooperation with said base member a passage through which said coolant flows, said passage having a base side and a heat transfer side; and a bellows-like flow straightening plate disposed between said heat radiation part and said base member in physical contact with said heat radiation part on one side and with said base member on the other side, wherein said bellows-like flow straightening plate is pressed against said base member and said heat radiation part without brazing thereto, and wherein said bellows-like flow straightening plate is formed to have a greater height (T 1 +α) than the height (T 1 ) of the inner frame of said heat sink body, wherein said flow straightening plate partitions said passage into a plurality of flow straightening channels that include base member-side flow straightening channels and heat transfer side flow straightening channels, said channels having an open portion along one longitudinal dimension and a closed portion along an opposite longitudinal dimension, with the open portion defining the heat transfer and base member sides.