SEAT BELT WITH PRE-TENSIONER
The seat belt incorporating the pretensioner automatically winds the seat belt upon front impact to reduce forward shifting of the passenger.
Upon front impact the pretensioner ignites the gas generator and emits gas with the SRS-ECU signal when the front impact sensor, attached to the front of the body, detects an impact that exceeds the criteria. By this gas pressure, a ball moves in the pipe and rotates the gear. This gear rotation operates the spool in the direction of retracting the belt, and the webbing is retracted.
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