Miniature reduction motors are compact in size, offering high transmission efficiency and precision, which is why they are favored by enterprises. However, during long-term use, frequent shaft breakage occurs, drawing our attention to this phenomenon.

When the concentricity is well-maintained during the assembly of micro-reduction motors, the output shaft of the motor only bears the rotational force, making operation very smooth. However, when the micro-reduction motor is connected to the reducer with misalignment, the output shaft has to withstand radial forces from the input end of the reducer. Prolonged exposure to these radial forces will force the motor's output shaft to bend, and the direction of the bend in the micro-reduction motor's shaft will continuously change as the output shaft rotates.

As the output shaft of a miniature reducer motor rotates one full turn, the direction of the lateral force changes by 360 degrees. When there is a significant concentricity error, this radial force causes the motor output shaft temperature to rise, continuously damaging its metallic structure. The radial force will exceed the radial force that the miniature reducer motor output shaft can withstand, leading to the fracture of the miniature reducer motor output shaft.

As the concentricity error of the miniature reducer motor increases, the time for the drive motor output shaft to break shortens. Therefore, when the drive motor output shaft breaks, the input end of the miniature reducer motor also bears radial forces from the motor. Hence, ensuring concentricity during assembly is crucial.