Patent ID: 6343760
Filing Date: 2002-02-05
Classification: B60R

Abstract:
A webbing sensor for a vehicle safety restraint retractor, the retractor comprising a rotatable spool on which seat belt webbing is wound, and means for biasing the spool in a webbing rewind direction,the sensor comprising: an inertial member, adapted to rotate with the spool, a pivotally mounted locking pawl for engaging the spool and locking it against rotation under emergency conditions, a calibration spring biasing the inertial member so that it tends to rotate with the spool unless there is a sudden acceleration or deceleration of a value such as to overcome the resilience of the spring, wherein the spring is connected between the inertial member and the pawl, so that relative rotation between the inertial member and the spool results in movement of both ends of the spring by approximately the same distance.