Patent ID: 7828391

Claim:
A seat belt system for a vehicle seat having a backrest which can be reclined through a range of reclined angles and having a retractor mounted within the backrest for allowing a seat belt to be drawn out and wound up in the retractor, comprising: the retractor having a locking device for locking the retractor thereby preventing drawing out of the seat belt; the retractor having an acceleration sensor for actuating the locking device; an angle detection device for detecting a reclining angle of the backrest; and a sensor controller responsive to the angle detection device that brings the acceleration sensor into an operable state enabling locking of the retractor when the reclining angle is within the range where the passenger wears the seat belt and brings the acceleration sensor into an inoperable state disabling locking of the retractor by the acceleration sensor when the reclining angle is within a range where the passenger does not wear the seat belt, and wherein the backrest of the seat is rotatably connected to a seat cushion and the sensor controller comprises: a posture controller for orienting the acceleration sensor in the vertical direction; and an interlocking member for allowing the posture controller to interlock with the angle detection device, wherein the angle detection device is a link mechanism that is disposed in a connecting portion between the backrest and the seat cushion so as to detect the reclined angle of the backrest and to rotate the interlocking member in accordance with the reclined angle, and wherein the posture controller of the sensor controller controls the acceleration sensor to be kept horizontal by means of the rotation of the interlocking member when the reclined angle is within the range where the passenger wears the seat belt, and the posture controller of the sensor controller does not interlock with the angle detection device when the reclining angle is within the range where the passenger does not wear the seat belt.