Planetary gear type transmission

A planetary gear type transmission comprising:

• a planetary gear mechanism including a sun gear, a ring gear, and a planetary carrier which all have the same axis, one of the sun gear, the ring gear and the planetary carrier serving as an input element connected to an input shaft, another one apart from the one serving as the input element serving as a reaction element, and the others apart from the one serving as the reaction element each serving as an output element;
• an output shaft having the same axis as the planetary gear mechanism;
• a sleeve having a cylindrical shape and supported so as to be movable in an axial direction by the output shaft;
• one of the output elements provided close to the axis while the other one of the output elements provided at a distance from the axis;
• an inner piece connected to the one of the output elements and connected to the sleeve while the sleeve is approaching the planetary gear mechanism, the inner piece including a first inner spline;
• an outer piece connected to the other one of the output elements and connected to the sleeve while the sleeve is separating from the planetary gear mechanism, the outer piece including a second outer spline;
• and
• the sleeve including a first outer spline at an inner peripheral surface and a second inner spline at an outer peripheral surface, the first outer spline fitted to the first inner spline and the second inner spline fitted to the second outer spline, and a distance between the second inner spline and the planetary gear mechanism being smaller than a distance between the first outer spline and the planetary gear mechanism.