Pre-activeSeat Belt Unit (PSB) Description and Operation

Description

The Pre-activeSeat Belt (PSB) ensures initial restraint performance by retracting the seat belt immediately before a collision or hazardous condition, and reinforces the action of the seat belt pretensioner, load limiter and airbags. In addition, it stabilizes the front and rear occupant against inertial and centrifugal forces by retracting the seat belt during sudden braking or cornering. It also warns the driver with seat belt vibration when the vehicle departs the lane or any other hazardous situation occurs.

Main Function

1. 1
   Full Retraction: Maintains a safer posture by strongly retracting the seat belt immediately before a collision. [Operating Conditions]

   A.	When the radar detects a frontal collision

   B.	During sudden braking

   C.	When the vehicle control function is turned off

2. 2
   Dynamic Support: Stabilizes the occupant against forward and centrifugal forces by retracting the seat belt during sudden braking or cornering. [Operating Conditions]

   A.	During sudden braking (forward force)

   B.	During sharp cornering (centrifugal force)

   C.	When sliding on an icy road

3. 3
   Slack Removal: If the seat belt is not fully fastened, it will not function normally in a vehicle collision. In this case, this system fully fastens the seat belt by slightly retracting the belt when the vehicle speed reaches 40 km/h.
4. 4
   Seat Belt Parking: After the seat belt is unbuckled, it returns to its original position within 3 seconds by retracting the belt. However, this function does not operate when the belt has already returned to its original position.