The invention discloses a center shaft torque sensing device of an
electric bicycle. The center shaft torque sensing device comprises a center shaft, a crankset and a shaft sleeve. The center shaft is penetratingly arranged in a bottom bracket of the bicycle, the crankset sleeves the center shaft, the shaft sleeve sleeves the center shaft and can peripherally deform when under
peripheral torsional force, one end of the shaft sleeve is fixed relative to the center shaft, the other end of the shaft sleeve is fixed relative to the crankset, a torque sensing
assembly capable of sensing the magnitude of the
peripheral torsional force on the shaft sleeve is arranged on the shaft sleeve, a torque
signal output wire of the torque sensing
assembly is connected with a
motor controller of the bicycle by a wire outlet device, the wire outlet device comprises a movable slide seat and a
fixed slide seat which can be in contact with each other in a clinging manner and can relatively slide, the movable slide seat is fixed to the shaft sleeve, the
fixed slide seat is fixed relative to the bottom bracket of the bicycle, the torque
signal output wire of the torque sensing
assembly is connected with the movable slide seat, and the
fixed slide seat is connected with the
motor controller by a torque
signal lead wire. The center shaft torque sensing device has the advantages of simple structure and stability in performance.