| 摘要 |
Provided is a power-assisted bicycle that can prevent oil from adhering to a control board and so on even if the control board and so on are disposed in a single-shaft motor drive unit. A deceleration mechanism 25 including a plurality of gear portions engaged with each other is disposed on the transmission path of an auxiliary driving force from a motor 21 to a force combining member 29. The motor 21, the central portion of a crank shaft 7a, the force combining member 29, and the deceleration mechanism 25 are disposed in a motor drive unit 20. The motor drive unit 20 includes a unit casing 22 that contains a control board 24b. The motor drive unit 20 contains an oil guard cover 50 that serves as a partition between the region of the deceleration mechanism 25 and the region of the control board 24b and prevents oil on the gear portions of the deceleration mechanism 25 from penetrating into the region of the control board 24b. |
