| 摘要 |
Provided is a power-assisted bicycle capable of adequately maintaining torque detection ability while allowing pedal pressing force to be reduced during pedaling when the remaining battery capacity has been exhausted. A cylindrical human-power transmission body (28) on which a magnetostriction generation unit (31b) of a torque sensor (31) is formed is disposed at the outer periphery of a crankshaft (7a), a resultant-force body (29) in which human-power drive force and auxiliary drive force from a motor (21) is combined is disposed at the outer periphery of the crankshaft (7a), and a reduction mechanism (25) having a plurality of reduction gear units (36c, 36d) and reduction gear support shaft units (36a, 36b) for supporting the reduction gear units (36c, 36d) is disposed in the auxiliary drive force transmission pathway that extends to the motor (21) and the resultant-force body (29). A one-way clutch (37) for disconnecting human-power drive force is disposed between either of the reduction gear units (36c, 36d) and the reduction gear support shaft units (36a, 36b). |
