Retractor pretensioner assembly

A seatbelt pretensioner system for use in a seatbelt pretensioning retractor assembly having a housing and a spindle, the seatbelt pretensioner system comprising:

• a pretensioner tube in fluid communication with a gas generator;
• a pretensioner rod having a proximal end portion disposed towards the gas generator and a distal end portion disposed at an exit of the pretensioner tube inside the pretensioner tube, the pretensioner rod having a chamfer formed in a distal end portion of the pretensioner rod;
• and
• a pretensioner wheel rotatably mounted to the housing and fixedly coupled to the spindle, the pretensioner wheel including a body portion having an annular shape and a plurality of vanes formed around a circumference of the body portion, the plurality of vanes each having a first sidewall and a second sidewall,
• wherein in a cross-sectional plane of the pretensioner wheel perpendicular to a rotational axis of the pretensioner wheel, the pretensioner wheel has a root circle defined by connecting each of root sections of the vanes and a tip circle defined by connecting each of tip points of the vanes,
• wherein a first point is defined on a surface of the first sidewall when a circle line defined between the tip circle and the root circle intersects with the first sidewall and a second point is defined on a surface of the second sidewall when the circle line intersects with the second sidewall such that a vane distance is defined between the first point and the second point in a pocket formed between the two vanes, and
• wherein the chamfer of the pretensioner rod has a chamfer length greater than the vane distance in the pocket.