| 摘要 |
PURPOSE:To retain the skew effect and reduce the loss of skew leakage flux by making the outside diameter of the end part of the iron core of a rotor smaller than that of the central part thereof and by making the central part and the end part have a plurality of gaps different in number from each other. CONSTITUTION:The iron core of the rotor is constituted in such a manner that gap length 7 between the iron core 3 of the stator and the iron cores 5 and 6 of the rotor is different by arranging in the central part an iron core part formed by laminating iron plates having a large outside diameter and by arranging at both ends thereof iron core parts 6 formed by laminating iron plates having a slightly smaller diameter than that of the former. Since gap length delta is large at the end part of the iron core in this way, the magnetic resistance of a gap 7 is large in proportion to the gap length delta at the iron core part 6. Therefore, even when large synthetic magnetomotive force which is not canceled is generated in the end part of the iron core by the skew, the skew leakage flux turns to be small in inverse proportion to delta, and by selecting the gap length delta properly, the loss of the skew leakage flux caused at the end of the iron core can be controlled to be small. |
