摘要 |
PURPOSE:To increase the cooling efficiency of a field coil by providing vent passages between a pole core and a field coil, and between the layers of the field coil, bridging a partition member between top washers, and providing an exhaust passage at the pole core head side of the top washer. CONSTITUTION:A first vent passages 60 are provided between a field core 10 and a field coil 11, a second vent passages 70 are provided between the layers of the field coil 11, a partition member 22 bridged between top washers 21 is provided, and an exhaust passage 80 which has a long axial length is provided at the head of the pole core 10 side of the top washer 21. The pressure of cooling air is enhanced by the member 22 to be flowed to the first passage 60 and from the vent passage 40 to the second vent passages 70, and the flowing velocity of the cooling air passed through the first and second passages 60, 70 can be accelerated. Further, the ventilating area of the cooling air to the coil 11 via the passage 70 can be remarkably increased. Further, since the passage 8 is formed to have a long axial groove, the ventilating area can be increased. |