Operation

The locking device by the seat belt attachment webbing has the task of preventing the belt from becoming loose on account of the counter-force created by the mass of the occupant of the seat when the force of the main spring for the power unit is reduces once it is fully extended.

The device is made up of an outer casing (14) with splining on the inner circumference, a connecting element (17) which can slide inside the casing (14) and a bowden cable (6) and retraction cable (16) for the actual webbing.

There is also a safety spring (13) and a locking ellipse (15) which have the task of allowing the movement of the connecting element and, consequently the webbing in one direction only (retraction); in effect, when the seat belt tends to become loose the locking ellipse thrust by the safety spring (13) tends to get stuck in the splining in the outer casing (14) circumference.

1. Bowden cable
2. Safety spring
3. Outer casing
4. Locking ellipse
5. Webbing retraction cable
6. Element connecting webbing retraction cable/end of bowden cable

Operation

NOTE The diagram shows the partial cross section of the deceleration sensor (5) which highlights the locking lever retaining tooth.