Tension reducing retractor with reduced velocity ratchet

A seat belt retractor comprising:

• a frame;
• a seat belt storage spool on which a seat belt is wound, said spool being rotatable relative to said frame about a spool axis in belt withdrawal and belt retraction directions;
• first and second springs acting in series between said frame and said spool for biasing said spool to rotate in the belt retraction direction, said first spring having a stronger spring force than a spring force of said second spring;
• a ratchet wheel between said first and second springs for blocking the spring force of said first spring from biasing said spool in the belt retraction direction, said ratchet wheel having a plurality of teeth, said ratchet wheel being rotatable about a wheel axis relative to said frame when blocking of the spring force of said first spring does not occur and being stationary relative to said frame when blocking does occur;
• a pawl movable to selectively engage a tooth of said ratchet wheel to prevent rotation of said ratchet wheel relative to said frame;
• an actuator for moving said pawl into position for engagement with said tooth;
• and
• an inertia mass member fixed in position on said ratchet wheel at a distance from said wheel axis for increasing the rotational inertia of said ratchet wheel and for retarding rotational velocity of said ratchet wheel upon release of said pawl from said ratchet wheel.