PURPOSE: To simplify the driving mechanism and increase strength by connecting a planetary gear carrier which holds the attitude of a pair of planetary gears meshed with a nonrevolution type hollow sun external gear and is revolution- driven by a driving source and a planetary roller housing which supports the axis parts of a pair of planetary rollers and holds the twisted attitude of an axle, by a connecting body.

CONSTITUTION: A pair of planetary gears 2 are meshed with a hallow sun external gear 1 fixed in revolution-disabled state, and the attitude of the planetary gear 2 is held, and revolved by a planetary gear carrier 3 which is revolution-driven by a driving source 4 and the non-revolution type sun external gear 1, and rotation and revolution are generated on the planetary gear 2. Independently of the planetary gear carrier 3, a planetary roller housing 8 which supports the shaft parts of a pair of planetary rollers 6 and holds an axle 7 in a twisted attitude is supported in turnable manner by a roller stand 12. The carrier 3 and the planetary roller housing 8 are connected by a connecting body 16, and the axle 7 of a pair of planetary rollers 6 and the axle 9 of a pair of planetary gears 2 are connected through a spindle 10 having a universal joint held on the connecting body 16.