Seat belt retractor with multi-level load limiting
US6669133B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2002 |
| Grant date | Dec 30, 2003 |
| Priority date | — |
| Expiry date | Sep 12, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60R2022/287
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A seat belt retractor has a spool mounted for rotation in the retractor for retraction or pay-out of seat belt webbing depending upon the rotation direction of the spool. A locking ring is attached to one end of the spool. A lock bar locks the locking ring against rotation when a crash is sensed. A load limiter allows further pay-out of the seat belt webbing after the spool has locked under the influence of a vehicle occupant's forward momentum. The load limiter is a torsion bar attached at one end to the locking ring and at the other end to the spool; and a wire releasably coupled in the force path between the spool and the locking ring. The resilient mechanism, i.e. the wire, decouples itself after a predetermined number of turns of the torsion bar. The thickness, length and composition of the wire, together with the number of wires may be chosen to suit a vehicle's crash criteria.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.