抄録
A planetary roller type speed reducer was developed for an electric wheel chair, in which the output speed is given by the rotational speed of the career. When estimating the required torque, the traction under an elastohydrodynamic condition was determined with a roller-on-disk type tester. As a result, the coefficient of traction in the linear region of the traction was adopted. The power performance of the planetary roller type speed reducer was determined with a test bench equipped with a real traction drive, where the variation in acceleration with torque was measured.