PRE-TENSIONER SEAT BELT CONSTRUCTION/OPERATION


BME081057630T01

Construction

.

1
Retainer
2
Flywheel
3
Hook spring
4
Lock gear
5
Pawl spring
6
Torsion bar
7
E-ring
8
Locking base
9
Pawl
10
Stopper
11
Spacer
12
Housing
13
Guide drum
14
Holder
15
Sensor case
16
Weight
17
Actuator
18
Chamber
19
Clutch gear
20
Gas generator
21
Case
22
Sealing pin
23
Pin holder
24
Inlay
25
Strip cutter
26
Strip
27
Clutch sleeve
28
Clutch pin
29
Chamber plate
30
Spring case
31
Bush
32
Spring
33
Spring cover

Operation

Before activation (Normal condition)

• The clutch sleeve is separated from the movement of the clutch gear.
• The clutch gear is connected to the torsion bar through in the guide drum, and rotates freely according to the movement of the belt.

1
Strip
2
Clutch sleeve
3
Torsion bar
4
Clutch gear
5
Belt

During activation

• The pre-tensioner operates as follows.
1. When the pre-tensioner receives a signal to operate from the SAS unit, the gas generator releases a gas, which increases the pressure of the chamber inner. This pushes the strip and causes it to expand.
2. The clutch sleeve rotates counterclockwise according to the movement of the strip.
3. The clutch pin engages the clutch gear by the rotation of the clutch sleeve, and then the clutch gear rotates the torsion bar and the guide drum together, and retracts the belt.

1
Strip
2
Clutch sleeve
3
Torsion bar
4
Clutch gear
5
Belt
6
Clutch pin
7
Gas