Seat Belt Pre-Tensioner With Load Limiter

COMPONENT PARTS

Seat belt pre-tensioner with Load limiter


DESCRIPTION

The seat belt system is equipped with pre-tensioner mechanism, load limiter mechanism, and ELR mechanism (front seat passenger restraint mechanism).

STRUCTURE












PRE-TENSIONER MECHANISM






- In a frontal collision that exceeds the specified limit, air bag sensor unit detects the collision, transmits an electrical signal to gas generator (3) in manifold case, and activates gas generator. Gas is generated.
- The pressure of the generated gas moves the ball (4) inside of pipe (6). The ball then presses ring gear (2) which is engaged to the pinion gear (1).
- The rotation of the ring gear rotates the shaft (5) in the retracting direction of the seat belt. Seat belt is retracted.

LOAD LIMITER (ELR) MECHANISM






- In a collision, when ELR shaft (2) is locked, a load caused by impact is applied to webbing (1)
- When a load is continuously applied to webbing and reaches or exceeds the specified level, a rotating force is applied to ELR shaft that is engaged to lock portion (4) and bobbin (3). ELR shaft twists.
- As ELR shaft is twisted, webbing is pulled out while keeping a certain level of tension and easing the impact to the chest of front seat passenger.