SEAT BELT PYROTECHNIC TENSIONER Russian patent published in 2000 - IPC

FIELD: transport engineering; car seat belts. SUBSTANCE: device has housing accommodating combination energy accumulator including cylindrical tube with piston, and power spring in compressed state between piston and tube bottom. Pyrotechnic gas generator with igniter built into piston is connected by flexible tie-rod, either directly or indirectly, with some part of seat belt, for instance, with its lock or with inertia reel drive. Power spring inertia trigger operating in case of emergency at preset critical deceleration of car, ignites pyrotechnic gas generator. Powerful pressure created in tube quickly moves piston and rod to provide tension of belt strap. Force (P₁) of compressed power spring is 1450-1550 N. Thrust sleeve holding tie-rod with piston in starting position is secured on tie-rod for slipping under action of force (P_max) of 1950-2050 N or higher. It provides increase in tie-rod travel at small overall dimensions of device. EFFECT: elimination of design drawbacks, reduced cost of production owing to unification of main parts at different design versions. 13 cl, 12 dwg