| 摘要 |
PROBLEM TO BE SOLVED: To improve a service life by constituting a planetary gear such that it can move in the radial direction with regard to the rotating line of a planet receiving base. SOLUTION: A planet receiving base has three shaft ends projecting from the surface thereof. The shaft end 8 is used for receiving a planetary gear and guiding it and is inserted into an opening 9 for receiving the shaft of the planetary gear. The opening 9 for receiving the shaft of the planetary gear has a circular cross section and the cross section of the shaft end is nearly elliptic. The ellipse is arranged such that the narrowest cross section is orthogonal to a rotating axis and the broadest cross section is put into contact with the opening 9 for bearing the shaft nearly at a pitch diameter (a little upper, depending on the shape). Since the elliptic cross section of the shaft end 8 has a shorter length than the cross section of the opening 9 for bearing the shaft, a specified amount of play A12 in the axial direction and a specified amount of play B in the radial direction. |
