Force limiting device in a safety belt retractor

摘要

A force limiting device for use in a safety belt retractor. The retractor has a hollow belt spool. A shaft axially extends through the belt spool. A pair of ratchet wheels are each connected to one axial end of the shaft. An internally threaded nut is coaxially accommodated within and connected to the belt spool for joint rotation and relative axial displacement. The shaft is externally threaded and engaged with the nut. The shaft has an axial abutment, and an energy dissipating sleeve of plastically deformable material is engaged axially between the nut and the axial abutment.