Belt tensioner for safety belt of motor vehicle, has continuous radial walls extending up to inner wall of housing, laterally limiting pressure chamber and connected together over bar that limits pressure chamber

摘要

The tensioner (1) has a rotary piston (5) driven by flow of gas to perform rotating movement. Planetary gears (31) transmit the rotating movement of the piston into a tensioning movement of a safety belt (3). The piston comprises an inner interlocked ring (32) and a bar (14). The bar limits a circular-cylindrical pressure chamber (33) formed between an inner wall of a cylindrical housing (4) and the ring. Two continuous radial walls (7, 8) are provided at the piston and extend up to the inner wall of the housing. The walls laterally limit the chamber and connected together over the bar.