Tensioner for safety belt - has two differing strength springs alternately coupled to reel by gearing

摘要

The seat belt reel has a main spring (13) and a weaker secondary spring (29). In the fully reeled in setting the main spring is coupled to the reel axle. The spring provides a strong retarding force as the belt is pulled out. At a set extension the main spring is uncoupled and the secondary spring operates with a weaker force, making the wearing of the belt more comfortable. A simple gearing, with a floating gear (17) and cam shaped gear wheels provide the alternate meshing with the two spring linked gears. USE/ADVANTAGE - Simple mechanical switching control for springs, improved comfort for wearer.