Electrically adjusted safety restraint system

摘要

A safety restraint system having a seat belt retractor actuated by an electric motor, a logic control responsive to the state of a buckle switch and the outputs of a motor current sensor, a motor terminal voltage sensor and a crash sensor for generating mode signals corresponding to the operational state of the system, and a motor power control responsive to the mode signals for adjusting the seat belt for optimum safety of the occupant. When the seat belt is buckled the logic control will sequentially generate signals activating the power control to energize the retractor's motor to snug up the seat belt against the occupant's shoulder, then reverse its direction to provide a predetermined slack. The crash sensor will cause the motor to be energized to remove most of the slack before the crash loads are imposed upon the seat belt and the retractor. Unbuckling the seat belt energized the motor to stow the seat belt. The system is also responsive to movements of the occupant beyond the limits of the provided slack which increase the seat belt's slack. Upon the detection of such movements, the system will after a predetermined delay return the seat belt to its initial adjusted state.