A stop device, comprising: a motor rotor assembly including a rotating shaft; a first shift lever fixedly connected to the rotating shaft, said first shift lever comprising a first shifting part rotating around an axis of the rotating shaft to form a first motion trajectory; a second shift lever rotatably connected to the first shift lever, said second shift lever comprising a second shifting part partially within the first motion trajectory, and the first shifting part being capable of driving the second shifting part to rotate around the axis of the rotating shaft to form a second motion trajectory; and a motor stator assembly sleeved on the rotating shaft and rotatably connected with the rotating shaft, the motor stator assembly comprising a stopping boss located on a periphery of the first motion trajectory and partially within the second motion trajectory, wherein the first shift lever rotates in a first direction such that a total rotation angle of the first shift lever is greater than 360° and less than 720°, and wherein when the rotating shaft rotates, the first shift lever and the second shift lever are driven by the rotating shaft; the stop device being characterized in that when the second shift lever is rotated such that the second shifting part is brought into contact with the stopping boss, the first shift lever continues to rotate until it comes into contact with the second shift lever such that the rotating shaft and the first shift lever stop rotating, and at this time, the rotating shaft rotates in a second direction opposite to the first direction to drive the first shift lever and the second shift lever to rotate in the second direction. a motor rotor assembly including a rotating shaft; a first shift lever fixedly connected to the rotating shaft, said first shift lever comprising a first shifting part rotating around an axis of the rotating shaft to form a first motion trajectory; a second shift lever rotatably connected to the first shift lever, said second shift lever comprising a second shifting part partially within the first motion trajectory, and the first shifting part being capable of driving the second shifting part to rotate around the axis of the rotating shaft to form a second motion trajectory; and a motor stator assembly sleeved on the rotating shaft and rotatably connected with the rotating shaft, the motor stator assembly comprising a stopping boss located on a periphery of the first motion trajectory and partially within the second motion trajectory, wherein the first shift lever rotates in a first direction such that a total rotation angle of the first shift lever is greater than 360° and less than 720°, and wherein when the rotating shaft rotates, the first shift lever and the second shift lever are driven by the rotating shaft; the stop device being characterized in that when the second shift lever is rotated such that the second shifting part is brought into contact with the stopping boss, the first shift lever continues to rotate until it comes into contact with the second shift lever such that the rotating shaft and the first shift lever stop rotating, and at this time, the rotating shaft rotates in a second direction opposite to the first direction to drive the first shift lever and the second shift lever to rotate in the second direction.