TRANSMISSION STRUCTURE OF HUB MOTOR

A transmission structure of a hub motor has a hub shell (10), an axle (20), a motor unit (30), and a clutch assembly (40, 40A). The clutch assembly (40, 40A) includes a driving ring (41, 41A), an output disc (42), a fixing base (43), a clutch disc (44, 44A), and a pressing ring (45). The motor unit (30) drives the driving ring (41, 41A) to rotate. The driving ring (41, 41A) drives the clutch disc (44, 44A) to rotate; the pressing ring (45) then pushes the clutch disc (44, 44A) to contact the output disc (42) and further drives the output disc (42) to rotate. The fixing base (43) is magnetic. The clutch disc (44, 44A) is magnetically attractable such that the clutch disc (44, 44A) separates from the output disc (42) when the motor unit (30) stops working.