×

Load limiting seat belt retractor with spiral turn limiter

  • US 9,469,272 B2
  • Filed: 03/06/2014
  • Issued: 10/18/2016
  • Est. Priority Date: 03/15/2013
  • Status: Active Grant
First Claim
Patent Images

1. A motor vehicle seat belt retractor having load limiting features for controlling restraint load acting on seat belt webbing stored on the retractor, the retractor of a type having a spool with a first end coupled to a tread head and a second end opposite the tread head, the spool rotatable with respect to a retractor frame, the spool storing the seat belt webbing wrapped thereon, and a locking mechanism for selectively locking the spool via locking of the tread head to provide vehicle occupant restraint, the retractor comprising:

  • a load limiting element having a first portion and a second portion, the second portion being rigidly coupled to the second end of the spool to prevent relative rotation between the second portion of the load limiting element and the second end of spool such that the spool rotates along with the second portion of the load limiting element when the locking mechanism is locked, the load limiting element limiting restraint loading of the seat belt webbing in response to locking of the locking mechanism, anda rotational displacement limiting mechanism for limiting the displacement of the second portion of the load limiting element relative to the first portion of the load limiting element, the rotational displacement limiting mechanism being fixed relative to the retractor frame when the locking mechanism is locked, the rotational displacement limiting mechanism having a cam forming a spiral flight and the rotational displacement limiting mechanism further having a cam follower engaging the spiral flight, wherein, in response to the locking of the locking mechanism, the load limiting element undergoes an initial angular displacement greater than 360 degrees of the second portion relative to the first portion along with a corresponding angular displacement of the spool relative to the tread head and the retractor frame, with the cam and the cam follower interengaging such that the cam follower translates along the spiral flight from an initial position toward an end position, wherein the cam follower will reach the end position of the spiral flight preventing further relative angular displacement between the second portion of the load limiting element and the first portion of the load limiting element beyond a predetermined maximum angular displacement.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×