Hitachi, Ltd.

Nissan Motor Company Limited

Shunji Ooki

Fumio Tajima

Yasushi Takano

Michiyuki Takagi

Masahide Kimura

Kanako Nemoto

Tsukasa Yamazaki

Yasushi Fujita

Akira Nezu

The vibration and noise excited by the electromagnetic exciting force in the radial direction of an electric motor are suppressed. In an electric motor, a rotoris divided into four rotor pieces, andfor an axial length of 2L of one group of the rotor core, and for example, the four rotor pieces, andare ideally 0.29L, 0.71L, 0.71L, and 0.29L in axial length in the axial direction, and permanent magnetsof the rotor pieces, andare arranged in the circumferential direction so that the phase differences of the electrical angle are 0, &#x3c0;, 0, and &#x3c0;. Further, when an effect is obtained even if the ideal axial length is changed, the tolerance of the aforementioned axial length is &#xb1;0.1L.

Electric motor

Growing community of inventors

Yokohama, Japan

Shunji Ooki