Passive vehicle occupant restraint belt system

In a passive occupant restraint belt system for vehicles which includes a restraining belt, apparatus for moving the belt from an occupant-restraining to occupant-releasing position in response to partial opening of a door of the vehicle comprising belt transfer means engaging the belt for moving the belt from the restraining to the releasing position and motion transmission means coupled to the belt transfer means for transmitting and amplifying opening motions of the door to the transfer means, the transmission means including (a) a motion amplifier mounted on one of the vehicle body and the door, (b) a folding linkage having one end attached to the other of the body and door and the other end coupled to an input component of the motion amplifier, and (c) means for controlling the linkage to maintain it in substantially its folded state during movement of the door from the closed to a partly open position, thus to transmit such door movement to the motion amplifier, and to cause the linkage to unfold during movement of the door from the partly open to the fully open position, and substantially to cease transmitting such door movement to the motion amplifier, whereby the bolt is moved substantially completely from the restraining to the releasing position, during movement of the door from the closed to the partly open position.