Stepper motor

A stepper motor, comprising:

• a rotor shaft;
• a steel magnet, sleeved and fixed to an outer peripheral side of the rotor shaft;
• a winding unit, sleeved to the rotor shaft and rotationally connected to the rotor shaft, wherein the winding unit includes two windings spaced apart from the steel magnet;
• and
• two flexible circuit boards, fixed to the winding unit and electrically connected to the winding unit;
• wherein each of the two windings includes:
• a housing, sleeved to the rotor shaft and rotationally connected to the rotor shaft;
• two skeletons, fixed to an inner peripheral side of the housing and coaxially disposed with the housing;
• and
• coils, wherein a respective coil of the coils is fixed to a respective skeleton of the two skeletons, wherein the respective skeleton includes two claw poles disposed opposite to each other, and the respective coil is disposed around outer peripheral sides of the two claw poles;
• wherein each respective flexible circuit board of the two flexible circuit boards is fixed to an outer peripheral side of the housing of a respective winding of the two windings and electrically connected to all coils in the respective winding, and the two flexible circuit boards have adjacent ends welded together to form electrical connection.