ROTATING ELECTRIC MACHINE

PROBLEM TO BE SOLVED: To reduce noise and windage loss, as well of a machine in the cource of operation by causing one end side of a cylindrical ventilating guide duct to be in a trumpet-like shape from its end part over to the inside. SOLUTION: An suction part 8 of the ventilating guide duct 1 of this rotating electric machine has a trumpet-like shape, and its cross section against the shaft 3 gradually becomes small as it leaves an intake surface 10 toward the inside. Accordingly, securing of a wind quantity necessary for cooling becomes easy, since it tends to take in a large amount of wind against a fan effect generated in the intake part 8 through the rotation of ribs 2. Additionally, the quantity of noise becomes small while the rotating electric machine is operated also, since its windage loss, etc., become hard to be generated in this area. Moreover, the side cross section of the guide duct 1 may be gradually decreased at a constant rate from the intake surface 10 up to suction surface 11. Consequently, reduction in the windage loss of the intake part of the ventilating guide duct becomes feasible and along with superior cooling effect and reduction in operation-time noise also become feasible.