The seat belt retractor is provided that comprises an electric motor; a spool operatively associated with the electric motor for winding and unwinding a seat belt for occupant restraint; and a controller. The controller can be configured to control a drive of the electric motor based on a seat belt storage...http://www.google.com.tw/patents/US20070084955?utm_source=gb-gplus-share專利 US20070084955 - Seat belt apparatus
