Retractor having a single sided energy absorbing spool

• US 5,613,647 A
• Filed: 04/29/1996
• Issued: 03/25/1997
• Est. Priority Date: 11/28/1994
• Status: Expired due to Fees

• Current Assignee: Breed Automotive Technology, Inc. (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Alliedsignal Inc. (Honeywell International Inc.)
• Inventors: Dybro, Niels, Miller, Harold J. III
• Primary Examiner(s): Jillions, John M.
• Application Number:
  US08/638,660
• Time in Patent Office: 330 Days
• Field of Search: 242/379.1, 242/376, 242/376.1, 242/587.1, 242/587.2, 242/587.3, 280/805, 280/806, 297/471, 297/472, 297/478, 297/480
• US Class Current: 242/376
• CPC Class Codes: B60R 22/34 Belt retractors, e.g. reels anchoring devices , e.g. guide loops , with means to tension the belt in an emergency B60R22/195
• CPC Class Codes: B60R 22/4676 comprising energy-absorbing means operating between belt reel and retractor frame

Abstract

An energy absorbing seat belt retractor comprising: a frame (22); a spool (24) rotatably mounted relatively to the spool including a lock wheel (71) having a plurality of lock teeth associated therewith and adapted to receive a seat belt thereabout; a lock pawl (77) for engaging the spool upon sensing a one of a vehicle deceleration and seat belt extraction above certain determinable levels; and movable nut (90)located in the spool and for prohibiting relative movement between the lock wheel and spool below a threshold input force level generated in part by occupant load on the seat belt and for generating a controlled energy dissipating reaction force on the seat belt after the input force exceeds the threshold level to permit a controlled rotation of the spool and the controlled pay out of the seat belt from the spool.

Claims

1. An energy absorbing seat belt retractor comprising:

a frame;

a spool rotatably mounted relatively to the frame for protracting and retracting a safety belt wound thereabout, including a web receiving, generally cylindrical portion about which the seat belt is wound, a web holding slot having;

a first part comprising a radial slot extending inward from the cylindrical portion and terminating at an inner end, a second part comprising an arcuate slot within the spool extending from the inner end of the first part through an angle of at least about 180 degrees and a third part comprising a slot extending outward to intersect the cylindrical portion,

a lock wheel operatively coupled to the spool, including a plurality of lock teeth associated therewith;

first means for engaging the spool upon sensing a one of a vehicle deceleration and seat belt extraction above certain determinable levels;

second means located within the spool joining the lock wheel to the spool for prohibiting relative movement therebetween below a threshold input force level generated in part by occupant load on the seat belt and for generating a controlled energy dissipating reaction force on the seat belt after the input force exceeds the threshold level to permit a controlled rotation of the spool and the controlled payout of the seat belt from the spool.

2. The device as defined in claim 1 wherein the second means includes an axle assembly (50) including third means (90, 90'"'"', 90") movably disposed therein for dissipating energy as it moves by one of extruding adjacent material, cutting adjacent spool material and crushing a deformable member disposed internal to the spool.

3. The device as defined in claim 2 wherein the axle assembly includes end parts fixed axially relative to the frame.

4. The device as defined in claim 2 wherein the third means includes a carrier member, including a splined and threaded nut translationally movable relative to one of the lock wheel and spool.

5. The device as defined in claim 4 wherein the carrier member includes a conically shaped surface butted against a mating conical surface on a translationally stationary member.

6. The device as defined in claim 4 including a deformable ring disposed adjacent the carrier member wherein the ring is deformed as the carrier member is forcibly moved thereagainst.

7. The device as defined in claim 4 wherein one of the spool and a member extending from the lock wheel includes a first set of splines and the other of the spool and the lock wheel includes threads and wherein the carrier member includes a mating set of splines and mating threads.

8. The device as defined in claim 1 wherein the inner end of the radial slot is arcuately shaped.

9. The device as defined in claim 1 wherein the second means includes a plurality of splines (30) formed about a central bore (28).