Take-up mechanism for safety belts

摘要

A take-up mechanism for the seat belt of a vehicle comprises an automatic belt winding assembly having a reel with a reel shaft for dispensing and rewinding the belt. A pull-up assembly for rewinding a belt of the winding assembly includes a rotary piston motor drivable by pressurized gas, usually generated from a pyrotechnic charge, and a ring which is co-rotatably connected to a rotary vane of the motor. The ring is coupleable to the reel shaft of the automatic winding assembly by engagement of a blocking element with a notched wheel co-rotatably mounted to the reel shaft. A sensor element is engageable with the notched wheel upon abrupt movement of the vehicle to block rotation of the reel in the dispensing direction. A control disc is rotatable with respect to the notched wheel and is engaged with the blocking element for moving the blocking element to engage the notched wheel upon the occurrence of either an abrupt vehicle motion or when the belt is moved in the dispensing direction abruptly. A locking mechanism is provided for preventing rotation of the ring in the belt dispensing direction.