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Short / On the move
A gentle pull lets the belt out. A sudden tug can trigger the retractor's locking mechanism. Look inside the system that makes both possible.
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The belt webbing is stored on a rotating spool inside the retractor. During ordinary movement, the spool lets the belt extend. In a belt-sensitive design, rapid webbing payout triggers a locking mechanism that restricts further extraction. The trigger responds to the belt's motion.
Vehicle-sensitive locking responds to changes in the car's motion or tilt, while belt-sensitive locking responds to rapid belt movement. A retractor can include both. These locking functions are separate from a crash pretensioner, which actively tightens the belt. The exact arrangement varies between systems.
Yes. A belt-sensitive retractor can respond to a sudden pull even when the vehicle itself is stationary.
No. Locking restricts webbing payout. A pretensioner tightens the belt as part of the vehicle's restraint response.
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