Progressive load limiter

摘要

A retractor includes a spool configured to selectively wind and unwind the webbing, a lock base configured to operate in a free position and a locked position, a first energy absorbing member coupled to the spool and the lock base, and a second energy absorbing member coupled to the spool and the lock base. When the lock base is in the free position, the spool and lock base freely rotate together when a force is applied on the spool through the webbing. When the lock base is in the locked position and a force is applied on the spool through the webbing, rotation of the spool is permitted while rotation of the lock base is prevented, such that the first energy absorbing member absorbs a first energy and the second energy absorbing member is configured to absorb a second energy after a predetermined rotation of the spool.

主权项

1. A retractor for use in an occupant restraint system having a seatbelt webbing, the retractor comprising:
a rotatable spool configured to selectively wind and unwind the webbing around the spool; a lock base configured to operate in a free position and a locked position; a first energy absorbing member coupled to the spool and the lock base; and a second energy absorbing member coupled to the spool and the lock base; wherein when the lock base is in the free position, the spool and lock base are configured to freely rotate together when a force is applied on the spool through the webbing; and wherein when the lock base is in the locked position and a force is applied on the spool by the webbing, energy is initially absorbed by only the first energy absorbing member and wherein after the spool rotates at least a predetermined amount the second energy absorbing member begins to absorb energy.