SPEED CHANGE TRANSMISSION UNIT

摘要

Rotation of an input axle (8) coaxially fitted to an output axle (9) by way of a bearing (16) is transmitted from a sun gear (11) to a gear part (13a) of a planetary pinion (13), which causes a gear part (13b) of the pinion (13) to roll along the inner circumference of a fixed ring gear (12). Thus, the rotation of the input axle (8) is transmitted to the output axle (9) through a carrier (14). As shown in (b) and (c), the gear part (13a) of the pinion (13) is positioned closer to the output axle (9) than the gear part (13b) of the pinion (13), which is the opposite arrangement to the conventional structure shown in (a). Therefore, the offset between the bearing (16) and the gear part (13a) can be reduced from L3 (conventional structure) to L6 in the case of (b) or 0 in the case of (c). Thus, the amount of radial displacement of the gear part (13a) relative to the sun gear (11) can be reduced and partial engagement between teeth of the sun gear (11) and the gear part (13a) can be reduced when the angle of intersection around the bearing (16) occurs between the input and output axles (8, 9) due to inclination of the output axle (9).