Seat Belt Systems: Description and Operation

Seat Belt Construction:

Seat Belt Construction

Seat Belt with ELR
The seat belt with Emergency Locking Retractor (ELR. is designed so that it locks immediately (to prevent the webbing from being pulled out of the retractor any further. when any of the following items is detected as exceeding each set value; speed at which the webbing is pulled out of the
retractor, acceleration or deceleration of the vehicle speed, and inclination.

Seat Belt with A-ELR
The automatic and emergency locking retractor (A-ELR. works as an Emergency Locking Retractor (ELR. till its webbing is pulled all the way out and then on as an Automatic Locking Retractor (ALR. till it is retracted fully.

ALR:
Automatically locks when the webbing is pulled out from the retractor and allowed to retract even a little.

Then the webbing can not be pulled out any further, unless it is wound all the way back into the retractor, which releases the lock and allows the webbing to be pulled out.

Seat Belt with Pretensioner
The seat belt with ELR and a pretensioner has a pretensioner mechanism which operates in linkage with the air bag in addition to the above described ELR. The pretensioner takes up the sag of the seat belt in occurrence of a front collision with an impact larger than a certain set value, thereby enhancing restraint performance.