Patent ID: 7635150

Claim:
An automotive pretensioner seatbelt system, including a seatbelt, comprising: a seatbelt webbing, a slip ring mounted to the outer side of a B-pillar, a pretensioner installed within the B-pillar, and a retractor fixed in the B-pillar, wherein one end of the webbing is fixed to an anchor site of the vehicle body, while the other end of the webbing goes through the slip ring and the pretensioner, and links to the retractor, wherein the pretensioner is provided between the slip ring and the retractor, and the pretensioner comprising: a stroke enlargement mechanism and a power source, the stroke enlargement mechanism having a fixed bracket and a movable bracket, the power source making the movable bracket both move and have a displacement when the seatbelt is actuated, the seatbelt webbing is wound around the fixed bracket and the movable bracket, the length of the seatbelt webbing retracted by the stroke enlargement mechanism is greater than the displacement of the movable bracket driven by the power source wherein the fixed bracket is fixed in the B-pillar, the movable component is a movable bracket, the fixed bracket and the movable bracket form a translational kinematic pair, and both brackets have a ladder-type structure with a series of shafts mounted between two side plates by bearings.