Seat belt tightening apparatus

• US 6,213,512 B1
• Filed: 12/14/1998
• Issued: 04/10/2001
• Est. Priority Date: 12/14/1998
• Status: Expired due to Term

• Current Assignee: TRW Inc. (Northrop Grumman Corporation)
• Original Assignee: TRW Inc. (Northrop Grumman Corporation)
• Inventors: Swann, Patrick A., Swann, Lauren E., Swann, Timothy A.
• Primary Examiner(s): Johnson, Brian L.
• Assistant Examiner(s): FISCHMANN, BRYAN R
• Application Number:
  US09/211,033
• Time in Patent Office: 848 Days
• Field of Search: 280/801.1, 280/806, 280/807, 180/268, 180/271, 297/477, 297/478, 297/480, 340/435, 340/436, 340/903
• US Class Current: 280/806
• CPC Class Codes: B60R 2021/0011 Rear collision or recoiling bounce after frontal collision
• CPC Class Codes: B60R 2022/4609 using a plurality of tensioners
• CPC Class Codes: B60R 2022/4666 characterised by electric actuators
• CPC Class Codes: B60R 2022/4685 with means to adjust or regulate the tensioning force in relation to external parameters
• CPC Class Codes: B60R 21/0134 responsive to imminent contact with an obstacle , e.g. using radar systems
• CPC Class Codes: B60R 22/46 Reels with means to tension the belt in an emergency by forced winding upelectrical circuits for triggering safety arrangements B60R21/01 ; tensioners using reels only guiding the belt during normal use, e.g. splitted reels B60R22/195

Abstract

A vehicle occupant protection system (10) includes a sensor (16) which is effective to sense a distance between a vehicle (12) and an object (14) adjacent to the vehicle (12). The sensor (16) also is effective to provide a sensor signal (18) indicative of the distance between the vehicle (12) and the adjacent object (14). The system (10) also includes a length of seat belt webbing (26) extensible about an occupant (28) of the vehicle. An actuatable mechanism (22) is operatively connected with the webbing (26). The actuatable mechanism (22) is operable to effect a tightening of the webbing (26) around the vehicle occupant (28) upon the sensor signal (18) indicating that the distance between the vehicle (12) and the adjacent object (14) is within a predetermined distance.

Claims

1. A vehicle occupant protection system for a vehicle comprising:

two sensors, a first sensor sensing a distance between the vehicle and an object adjacent to the vehicle and generating a first sensor signal indicative of the distance between the vehicle and the adjacent object, a second sensor sensing the occurrence of a vehicle crash event and generating a second sensor signal indicative of the occurrence of the vehicle crash event;

a seat belt assembly, the seat belt assembly including a length of webbing, a buckle tongue, and a buckle, the length of webbing being extensible about an occupant of the vehicle, the buckle tongue being slidably attached to the webbing, the buckle releasably receiving the buckle tongue;

a retractor assembly, the retractor assembly having an actuator, a spool, and a spring, the retractor being located on a side of the vehicle seat opposite the buckle, the spool being rotatable to wind a portion of the webbing around the spool, the spring applying a first tightening force to the webbing by rotating the spool to wind a portion of the webbing around the spool;

the actuator applying a second tightening force to the webbing by further rotating the spool to wind a portion of the webbing around the spool when the first sensor signal indicates that the distance between the vehicle and the adjacent object is within a predetermined distance, the second tightening force being greater than the first tightening force; and

an actuatable pretensioner device being attached to the buckle, the actuatable pretensioner causing downward movement of the buckle to apply a third tightening force to the webbing when the second sensor signal indicates the occurrence of the vehicle crash event, the third tightening force being greater than both the first and the second tightening forces.

2. The vehicle occupant protection system as in claim 1 further being defined by:

the actuator being an electric motor.

3. The vehicle occupant protection system as in claim 1 further being defined by:

an electronic control unit receiving the first and the second sensor signals and controlling the actuation of the actuator of the retractor assembly and the actuatable pretensioner.

4. The vehicle occupant protection system as in claim 3 further being defined by:

the electronic control unit recording a minimum pay-out point of webbing from the spool of the retractor assembly when the buckle tongue is first received by the buckle, upon receiving the first sensor signal the electric control unit controlling the actuator of the retractor assembly to rewind the webbing about the spool to the minimum pay-out point.

5. The vehicle occupant protection system as in claim 4 further being defined by:

the buckle having a switch with a first condition indicative of the buckle tongue being unbuckled and a second condition indicative of the buckle tongue being buckled, the electronic motor controller recording the minimum pay-out point when the buckle switch changes from the first condition to the second condition.

6. The vehicle occupant protection system as in claim 5 further being defined by:

the electronic control unit controlling the actuator to vary the rate of the second tightening force dependent upon the distance between the vehicle and the adjacent object sensed by the first sensor.

7. The vehicle occupant protection system as in claim 1 further being defined by:

the retractor assembly further including a ratchet wheel and a pawl for locking rotation of the spool within the retractor assembly, the ratchet wheel and the pawl locking rotation of the spool when the actuatable pretensioner causes downward movement of the buckle.

8. The vehicle occupant protection system as in claim 1 further being defined by:

the second tightening force of the webbing occurring at a slower rate of speed than the third tightening force of the webbing.