What is a Pretensioner Seat belt
Release time:
2022-04-01
The feature of the Pretensioner Seat belt is that when the car collides| the seat belt can be tightened in advance to improve the restraint effect on the occupant's body| The occupant leans forward and avoids collision with the steering wheel| instrument panel and windshield|
The feature of the Pretensioner Seat belt is that when the car collides, the seat belt can be tightened in advance to improve the restraint effect on the occupant's body. The occupant leans forward and avoids collision with the steering wheel, instrument panel and windshield.
When the occupant has not moved forward, the pre-tightening seat belt will first tighten the webbing, immediately fix the occupant on the seat, and then lock the webbing to prevent the occupant from leaning forward, effectively protecting the safety of the occupant. The retractor that plays the main role in the pretensioner seat belt is different from the ordinary seat belt. In addition to the function of retracting and unwinding the webbing of the ordinary retractor, it also has the function of strengthening the restraint force on the occupants in a very short time when the vehicle speed changes sharply. Therefore, the Pretensioner Seat belt also includes a control device and a pretensioner.
The structure of the Pretensioner Seat belt:
1. Sensor
Shared with SRS airbag system. The Pretensioner Seat belt and the SRS airbag system are activated at the same time when an impact from the front above the specified value is detected.
2. Power unit
It consists of a heater, ignition agent, propellant, piston, etc. for ignition, and it ignites according to the signal from the sensor. The generated air pressure is used to push the piston in the cylinder, thereby generating the power to tighten the seat belt. Ingredients with good heat resistance and durability are added to the most important propellant in the pretensioner.
3. Tightening device
The Pretensioner Seat belt passes between the fixed gear and the moving gear and is normally used without any resistance. The thrust generated after the power unit is activated is converted into rotary motion through the pulley. In addition, when the movable gear rotates, the seat belt between the movable gear and the fixed gear is clamped, so that the seat belt is tightened while rotating.
4. Anti-reverse structure
Once the Pretensioner Seat belt is tightened, the tension in the passenger seat belt engages and maintains the anti-reverse rotation gear. To surely prevent reverse rotation, the gears are engaged in four places.
Related News