Patent ID: 8151868

Claim:
A cooler of a built-up type for cooling electronic parts from both sides thereof, comprising: a plurality of flat cooling tubes provided with a refrigerant flow passage through which a cooling medium flows and arranged in layers, so as to sandwich and hold the electronic parts at both sides thereof; and a supply header section for supplying the cooling medium to each of the refrigerant flow passages; and a discharge header section for discharging the cooling medium from each of the refrigerant flow passages; wherein each of the cooling tubes has protruding pipe parts opening and protruding toward the direction of built-up of the cooling tubes, neighboring cooling tubes make the refrigerant flow passages thereof communicate with each other by inserting the protruding pipe parts into each other and, at the same time, joining the sidewalls of the protruding pipe parts to each other, and thus forming the supply header section and the discharge header section, the electronic part contacts a plate-shaped surface of the cooler, the protruding pipe parts are formed so as to protrude in a vertical direction from the plate-shaped surface of the cooler, and a diaphragm part which deforms in a direction of built-up is formed on a periphery of a root part of at least one of the protruding pipe parts of each tube.