| 摘要 |
PURPOSE:To eliminate the inequality of the generation of a rectifying spark, and to reduce the roughening defect of a commutator and the abrasion of a brush by surrounding a coil, rectification thereof is lastly completed, in adjacent slots and a coil, rectification thereof is completed first, by a magnetic circuit consisting of a magnetic material and magnetically coupling the coils. CONSTITUTION:Magnetic short-circuit pipes 14 composed of the magnetic material in number equal to the number of the slots are mounted to at least one part of total coil length such as one coil end section so as to magnetically couple the coils 10c1, 10d1, rectification thereof is lastly completed, in the same slot 9a1 and the coils 10a2, 10b2, rectification thereof is completed first, in the adjacent slot 9a2. Consequently, mutual induction action functions to the coils 10a2, 10b2 in the direction inhibiting the leakage flux of the coils 10a2, 10b2, and the value of the effective inductance of the coils 10a1, 10b1 and 10c1, 10d1 can be brought close. Accordingly, the state of sliding of the brush can be improved, and the roughening defect of the commutator and the abrasion of the brush can be reduced. |
