Safety belt system and belt winder

A safety belt system comprising:

• a safety belt for restraining an occupant in a seat;
• a tongue plate arranged on the safety belt;
• a buckle detachably engaged with the tongue plate;
• a belt reel for tightening or loosing the safety belt;
• an electric motor for driving the belt reel, the motor comprising:
• a stator;
• and
• a rotor rotatably mounted to the stator, the rotor comprising an motor shaft, a commutator fixed to the motor shaft, a rotor core fixed to the motor shaft and rotor windings wound about teeth of the rotor core and electrically connected to segments of the commutator, the rotor windings comprises a plurality of winding units, each winding unit comprising at least two coils, the coils of each winding unit being wound about the same teeth and electrically connected to a same pair of segments, in parallel;
• a detection unit for detecting whether a predefined event is happening or is imminent;
• a controller for controlling the motor based on the detecting result of the detection unit;
• and
• a transmission unit coupled between the motor shaft and a central shaft of the belt reel, the motor driving the belt reel via the transmission unit.

A belt winder for a safety belt system comprising:

• a belt reel for tightening or loosing the safety belt;
• an electric motor for driving the belt reel, the motor comprising a stator and a rotor rotatably mounted to the stator, the rotor comprising an motor shaft, a commutator fixed to the motor shaft, a rotor core fixed to the motor shaft and rotor windings wound about teeth of the rotor core and electrically connected to segments of the commutator, the rotor windings comprises a plurality of winding units, each winding unit comprising at least two coils, the coils of each winding unit being wound about the same teeth and electrically connected to a same pair of segments, in parallel;
• and
• a transmission unit coupled between the motor shaft and a central shaft of the belt reel, the motor driving the belt reel via the transmission unit.