초록 ▼

A sensor of Giant magneto-resistive (GMR) type is attached to a seat belt anchor bracket. A seat belt passes through an opening in the bracket and is doubled back and sewn to form a loop. A magnet positioned on a sliding carriage is biased away from the sensor by springs. A seat belt loops around th

A sensor of Giant magneto-resistive (GMR) type is attached to a seat belt anchor bracket. A seat belt passes through an opening in the bracket and is doubled back and sewn to form a loop. A magnet positioned on a sliding carriage is biased away from the sensor by springs. A seat belt loops around the carriage, and when tension is applied to the belt, the carriage with the magnet is drawn against the springs toward the GMR sensor. The GMR sensor measures the magnetic field present at the sensor and a microprocessor determines belt tension based on the known spring constants and the strength of measured magnetic field which is correlated with displacement of the magnet.

대표청구항 ▼

[ What is claimed is:] [1.] A seat belt tension sensor comprising:a bracket adapted to be attached to a structural number of a passenger vehicle, the bracket having portions defining an opening through which a seat belt is looped, wherein the bracket has a seat belt restraining side;a carriage posit

[ What is claimed is:] [1.] A seat belt tension sensor comprising:a bracket adapted to be attached to a structural number of a passenger vehicle, the bracket having portions defining an opening through which a seat belt is looped, wherein the bracket has a seat belt restraining side;a carriage positioned within the bracket opening and movable toward the restraining side;a magnetic field sensor mounted on the restraining side of the bracket;a magnet mounted on the carriage for motion toward the sensor mounted on the restraining side; andat least one spring positioned between the carriage and the restraining side, biasing the carriage away from the restraining side, wherein the carriage moves toward the restraining side when tension is applied to the seat belt.