| 摘要 |
PURPOSE:To preferably cool a field coil by providing a vent barrier for guiding supplied air from the rim side of a rotor to a gap between adjacent coil rims of the coil, thereby strongly ventilating the supplied air via the barrier to the bar for ventilation. CONSTITUTION:The sectional shape of a field coil 1 is formed to be alternately telescoped to the outer peripheral surface 1a side and the inner peripheral surface side 1b in a irregular shape. A block 3a of an insulator is provided between core side insulators 3 of the inner peripheral surface 1b and the outer periphery of the body of the core 2 to secure the coil 1 and the core 2. The portion having no block 3a is formed as an air gap 4 for ventilation. A plurality of vent ducts 5 are provided to communicate with the gap 4 at the chip of the core 2. A coil rim gap 4a which communicates with the gap 4 is formed between the rim side end 1e of the coil 1 and the rim 6 of the rotor. An arcuate-shaped vent barrier 7 is formed in an entire axial length in contact with the end faces 1c, 1c of the rim sides of the adjacent coils 1, 1. In this manner, the inner peripheral surface of the field coil can be sufficiently cooled without disturbing the ventilating cooling of the outer peripheral surface of the field coil. |
