Abstract: A shroud 15 attached to an air discharge side of a radiator 13 narrows toward a centrifugal-flow-type rotary fan 11 and forms a cylindrical shape. A surrounding portion 17 is provided so as to surround the rotary fan 11, and a guide portion 19 extending in the centrifugal direction of the rotary fan 11 is provided at the end of the surrounding portion 17. The length of the guide portion 19 is about 6% the diameter of the rotary fan 11. Since this mitigates turbulence of centrifugally flowing air 21 flowing out of the rotary fan 11 and suppress a drop in the amount of air passing through the radiator 13, the cooling capacity of the radiator 13 can be enhanced.

Abstract: A shroud 15 attached to an air discharge side of a radiator 13 narrows toward a centrifugal-flow-type rotary fan 11 and forms a cylindrical shape. A surrounding portion 17 is provided so as to surround the rotary fan 11. A guide portion 23 extending in the centrifugal direction of the rotary fan 11 is provided at a circumferential edge portion of the surrounding portion 17. A cylindrical portion 19, which is smaller in diameter than the surrounding portion 17 is provided inside the surrounding portion 17, and an upper portion of the cylindrical portion 19 is fixed to the wall surface of the shroud 15. A lower portion of the cylindrical portion 19 is fixed by a fixing portion 21 having an inner diameter equal to the diameter of the cylindrical portion and an outer diameter equal to the diameter of the surrounding portion 17.