Seat belt retractor with tension relief mechanism

摘要

The present invention is directed to a tension relief mechanism for a safety belt retractor that can be selectively actuated for adjusting the tension exerted on the safety belt. The tension relief mechanism is operable for permitting the seat occupant to selectively vary the loading exerted on a counterspring for counteracting the retractive biasing exerted on the safety belt by the retractor rewind spring. The tension relief mechanism is actuated in response to withdrawal of a predetermined length of the safety belt. Thereafter, the withdrawal and subsequent retraction of an additional incremental length of the safety belt causes loading to be exerted on the counterspring. Thus, the residual tension exerted on the safety belt by the retractor is proportional to the magnitude of the loading applied to the counterspring which, in turn, is proportional to the incremental length of additional safety belt withdrawn following actuation of the tension relief mechanism.