| 摘要 |
A speed reducer (49) for a walk assist apparatus comprises first-third planetary gear mechanisms (P1, P2, P3) between an input shaft (Si) connected to a motor (48) and an output shaft (So). The second planetary gear mechanism (P2) is provided radially outside the first planetary gear mechanism (P1) connected to the input shaft (Si), and the third planetary gear mechanism (P3) is provided outside, in an axis (L) direction, the first planetary gear mechanism (P1). As a consequence, the thickness of the speed reducer (49) can be made less than the case where the rotation of the input shaft (Si) is reduced in three stages by the first-third planetary gear mechanisms (P1, P2, P3) and transmitted to the output shaft (So) with all the planetary gear mechanisms (P1, P2, P3) laid over each other in the axis (L) direction. This results that the appearance of the walk assist apparatus when worn by a user is improved. |
