Patent ID: 8262133
Filing Date: 2012-09-11
Classification: B60R

Abstract:
1. A seat belt retractor adapted for use with a seat belt presenting a first tensile load, said retractor comprising: a tensioning mechanism coupled to the belt and including an active material element operable to undergo a reversible change in fundamental property when exposed to or occluded from an activation signal, said mechanism being configured to selectively adjust the tension in the belt to a second tensile load, as a result of the change, wherein the mechanism includes first and second inter-engaged parts, and the first part is able to transmit a first maximum torque or force to the second part when the element is activated and a second maximum torque or force when deactivated, a plurality of torque-transmitting spheres are fixed to a first of the parts and contact the other, so as to be intermediately disposed therebetween, and the element is operable to cause the parts to relatively translate so as to reduce or increase the plurality of spheres.