NOVELTY - The device (10) has a case (20) where a heat generating structure (21) is accommodated in an inside. An air blower (30) is provided to suck the air within the case so as to generate an air flow in the case. An air path (40) is provided to guide the air positioned at an air flow direction rear side of the heat generating structure so as to cool the heat generating structure to the air blower. A cooling unit (41) is provided in the air path so as to cool the air and pass air through the inside of air path. The cooling unit is provided in the inside or exterior of air flow path.    USE - Device for cooling cools heat generating structure such as electronic components such as battery, inverter, motor, and internal combustion engine used in vehicle by ventilation generated using air blower such as centrifugal air blowers such as turbo fan and axial-flow-type air blower such as propeller fan.    ADVANTAGE - The cooling unit is provided in the air path so as to cool the air and pass air through the inside of air path so that the air is cooled by the cooling unit positioned at the air flow path between the heat generating structure and air blower and temperature falls even when the air is inhaled after the air blower exchanges heat with the heat generating structure so that the heat of air passing through the inside of duct is thermally radiated through the rib in the exterior of the cooling device, and temperature falls so as to suppress the deterioration of material with the heat in which air, and to suppress the heat deformation of the drive portion of the air blower. Thus, the deterioration of air blower and the fall of ventilation output caused by the generation of heat are avoided effectively. Hence, the efficiency of thermal radiation by the rib is prevented from impairing.    DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of the cooling device.    Device for cooling heat generating structure (10)    Case of device for cooling heat generating structure (20)    Heat generating structure (21)    Air blower (30)    Air path (40)    Cooling unit (41)