| 摘要 |
<p>An anchor plate (102) operatively coupled to a seat belt (14) incorporates a slot (110) that slideably engages an anchor bolt (112), which is biased therein by a spring (104). A tension in the seat belt (14) causes a deflection of the spring (104) and an associated motion of the anchor bolt (112) in the slot (110), which is sensed by a proximity sensor (106) on the anchor plate (102). In another aspect, a carriage (214) is adapted to slide relative to a bracket (202), and a first spring (104) is operative between the carriage (214) and the bracket (202) so as to bias the carriage (214) relative to the bracket (202) in a direction opposite to a first direction. Either the bracket (202) is operatively coupled to a vehicle frame (24) with an anchor bolt (112) and the seat belt (14) operatively engages the carriage (214), or vice versa. A tension in the seat belt (14), when reacted by the anchor bolt (112), causes an associated motion of the carriage (214) in the first direction, which is sensed by a displacement sensor (230). In one embodiment, a second spring (220.2) is operative between the carriage (214) and the bracket (202) so as to bias the carriage (214) in the first direction relative to said bracket (202), thereby substantially eliminating slack. One embodiment of the displacement sensor (230) comprises a magnetic sensor (230) coupled to the bracket (202), which measures the magnetic field between a pair of magnets (232.1, 232.2) having crossed pole orientations, operatively coupled to the carriage (214). In another aspect, a second carriage (314) and associated displacement sensor (330) provide an additional measure of tension.</p> |
