| 摘要 |
In an electric motor having high-speed and low-speed brushes, durability is improved and vibration/noise is reduced. The electric motor has a low-speed brush 21 a, a high-speed brush 21 b, and a common brush 21 c. Formed in the electric motor are a first coil 7 A 1 which is wound between given slots 11, and a second coil 7 A 2 which is wound in a direction opposite to a direction of the first coil 7 A 1 between slots 11 existing at positions point-symmetric to the given slots 11 with respect to a center of a rotation shaft. An armature coil 7 is formed by the first and second coils 7 A 1 and 7 A 2. If the armature coil 7 is short-circuited by the high-speed brush 21 b, the first coil 7 A 1 and the second coil 7 A 2 of the short-circuited armature coil 7 exist at positions symmetric to each other with respect to an axis line extending through the center of the high-speed brush 21 b and the center of the rotation shaft.
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