A seat belt retractor includes a mechanism for keeping the belt reel from rotating in the winding direction at the urging of the winding spring when the reel is at an automatically memorized rotational position. The mechanism comprises an internal toothed gear wheel affixed to the reel shaft and which...http://www.google.com/patents/US4494709?utm_source=gb-gplus-sharePatent US4494709 - Seat belt retractor with an automatically memorized tensionless position
