| 摘要 |
PURPOSE:To contrive to miniaturize a bearing bracket and rotary shaft by such an arrangement wherein the diameter of a stator frame is reduced by composing a ventilation passage way rationally. CONSTITUTION:A ventilation gap 16a is interconnected to the ventilation route 9 of a stator frame ventilation portion 7a through an interconnected ventilation route 18 which pierces through the foot portion 7g and the bottom plate 7h of the stator frame, and further, the interconnected ventilation route 18, at the side of the bottom plate 7h of the stator frame, is opened into an air cooler 10 at a position located outward the foot portion 7g of the stator frame. With this, cooling wind flowing through the ventilation gap 16a reaches the ventilation route 9 passing through the interconnected ventilation route 18, therefore it becomes unnecessary to provide a ventilating hole in the stator frame bottom plate 7h at a position between a stator core 6 and the stator frame leg portion 7g, and such a space for a ventilating hole which has so far been necessary for a conventional device is no longer required. Due to this structure, the stator frame 7 becomes smaller, and in connection with this, a bearing bracket 11 also becomes smaller in diameter. |
