| 摘要 |
<p>A configuration having a reduction gear, an electric motor, and a speed change mechanism, which are arranged side by side along an axle, makes a device compact. A speed change mechanism (11), a reduction mechanism (10), and a drive motor (8) are arranged within the rear hub (1) of an electrically assisted bicycle or an electric two-wheeled vehicle so as to be located side by side in the axial direction of the axle (14). The speed change mechanism (11) is provided with a sun gear (11a) for the speed changer, planetary gears (11b) for the speed changer, and a planetary carrier (11c) for the speed changer and transmits a pedaling force to the drive wheel. The reduction mechanism (10) is provided with a sun gear (10a) for the reduction gear, and planetary gears (10b) for the reduction gear and transmits a drive force, which is transmitted from the motor output shaft (8a) of the drive motor (8), to the drive wheel. The planetary gears (10b) for the reduction gear are supported by the planetary carrier (11c) for the speed changer. A speed change control mechanism (15) changes speed by switching, through a clutch member (16a) provided between the axle (14) and the sun gear (11a) for the speed changer, the sun gear (11a) for the speed changer between a state in which the sun gear (11a) can rotate around the axle (14) and a state in which the sun gear (11a) cannot rotate around the axle (14). The opposite ends of the axle (14) in the axial direction thereof are supported by a frame (6).</p> |
