Seat belt retractor system, seat belt apparatus, and vehicle with a seat belt apparatus

摘要

A technology is provided for rationalistically controlling a seat belt retractor which is capable of winding and unwinding a seat belt for occupant restraint by means of an electric motor and to therefore provide a technology effective for ensuring the removal of slack of the seat belt, with controlling the restraining feeling of a vehicle occupant as little as possible. A seat belt retractor 1 of a seat belt apparatus 100 to be installed in a vehicle is adapted to control a motor to perform an action of increasing seat belt tension to wind up a seat belt 3 which is excessively unwound from the spool when a vehicle occupant wears the seat belt and to be driven according to such a setting that, at the initial stage of the action of increasing the seat belt tension, the tension increasing rate until the seat belt tension reaches a target tension is lower than a predetermined criterion value of restraining force (Fig. 1).