Electric bicycle

摘要

An electric bicycle is provided that can increase the diameter of the joining section between a crankshaft and a crank arm, suppress an increase in manufacturing cost, and minimize a size increase of a hanger with a torque sensor disposed in the hanger. A crankshaft 17 is divided into a crankshaft body 17A on the periphery of which a torque sensor 23 is disposed, and an auxiliary crankshaft 17B connected to one side of the crankshaft body 17A. A diameter D1 of the joining section between the auxiliary crankshaft 17B and a crank arm 18B and a diameter D3 of the joining section between the crankshaft body 17A and a crank arm 18A are larger than a diameter D2 of the connecting section between the crankshaft body 17A and the auxiliary crankshaft 17B.

主权项

1. An electric bicycle that can be driven by adding an auxiliary driving force generated by an electric motor to a human driving force generated by a pedal force from a pedal, the electric bicycle comprising:
a torque sensor that detects a force corresponding to a pedal force with a crankshaft rotatably disposed in a hanger coupled to a lower end of a vertical pipe, wherein the crankshaft is divided into a crankshaft body on a periphery of which the torque sensor is disposed, and an auxiliary crankshaft connected to one side of the crankshaft body, a diameter of a joining section between the auxiliary crankshaft and a crank arm and a diameter of a joining section between the crankshaft body and the crank arm are larger than a diameter of a connecting section between the crankshaft body and the auxiliary crankshaft, a point of the crankshaft body near a joining section between the crankshaft body and the auxiliary crankshaft is rotatably supported by a bearing, a wire guide member is disposed between the bearing and a metallic inner cylinder disposed in the hanger, and the torque sensor is connected to a torque sensor connecting wire that is laterally extended out of the hanger through the wire guide member.