| 摘要 |
PROBLEM TO BE SOLVED: To provide a drive unit for electric vehicle embodied in a compact and lightweight construction, which uses a planetary gear speed reducer equipped with no ring gear.SOLUTION: A carrier 23 of a planetary gear speed reducer 12 is fixed to an inside circumferential surface of a motor rotor 21, and a pinion gear 22 is borne by a pinion pin 24 rotatably to the carrier 23, the pinion gear 22 having two rows of toothed parts 22a and 22b arranged in the axial direction, and a sun gear 33 meshing with one toothed part 22b of the pinion gear 22 is secured to a housing 15, while an output gear 31 to mesh with the another toothed part 22a of the pinion gear 22 is provided on the output shaft 13 of a hub unit 14. Numbers of teeth of the output gear 31 and the sun gear 33 and the numbers of teeth of the two rows of toothed parts 22a and 22b are set so that the rotation of the motor rotor 21 is transmitted to the output shaft 13 while being decelerated. |
