Safety belt clamp apparatus, occupant restraint system and method

• US 4,306,735 A
• Filed: 02/08/1979
• Issued: 12/22/1981
• Est. Priority Date: 11/30/1976
• Status: Expired due to Term

• Current Assignee: Allied Corp. (Honeywell International Inc.)
• Original Assignee: Allied Chemical Corporation (Honeywell International Inc.)
• Inventors: Stephenson, Robert L., Weman, Per O., Pfeiffer, Robert C.
• Primary Examiner(s): Silverstrim, John P.
• Application Number:
  US06/010,455
• Time in Patent Office: 1,048 Days
• Field of Search: 280/807, 280/808, 280/801, 280/805, 280/806, 297/476, 297/479, 242/107.7, 242/107.4 R, 242/107.4 D, 242/107.2, 242/107.3, 242/84.52 A
• US Class Current: 280/807
• CPC Class Codes: B60R 21/18 the inflatable member formed as a belt or harness or combined with a belt or harness arrangement
• CPC Class Codes: B60R 22/1855 the means being sensitive to belt tension

Abstract

An improved belt clamp apparatus for a vehicle occupant safety restraint system includes: a lever, a clamp bar, a mounting device for movably mounting the bar on the lever, a crest on the bar, and a first spring for biasing the lever to a non-clamping position. The bar is movable on the crest for applying a substantially uniform force over an area of contact on a safety belt. The belt clamp apparatus may be used in a variety of ways in an improved occupant restraint system such as to provide: a belt sensitive restraint system, a vehicle sensitive restraint system, a dual sensitive restraint system, or a force limiting restraint system. The invention also relates to a method for absorbing unwinding force and a method for reducing undesired unwinding of the belt.

Claims

1. A safety restraint system for a seated occupant in a vehicle, said system having a safety belt means passing over a shoulder of said seated occupant, said system comprising:

a belt clamp apparatus wherein said safety belt means movable through said clamp apparatus in a first direction and in an opposite second direction, said clamp apparatus resisting movement of said belt in said first direction when a force above a first predetermined amount is applied to said belt in said first direction, said clamp apparatus including a lever pivotable on a first shaft, said lever having a clamping position and a non-clamping position, and a first biasing means biasing said lever to its non-clamping position, a clamp bar having a first surface for contacting a portion of said belt, a mounting means on said lever for movably mounting said bar on said lever, said mounting means comprising a channel in said lever, means for retaining said bar in said mounting means of said lever, said retaining means comprising lip means associated with said channel, said clamp bar being freely movable within said channel, and pivot means on a second surface of said clamp bar opposite from said first surface, said clamp bar being movable on said pivot means with respect to said lever for applying a substantially uniform force over an area of contact of said belt; and

a retractor mounted in said vehicle below said belt clamp apparatus for allowing unwinding of said safety means in a first direction out of said retractor and for winding said belt means in a second opposite direction into said retractor.

2. The safety restraint system of claim 1 wherein said belt means further comprises an inflatable portion and means for inflating said inflatable portion.

3. The safety restraint system according to claim 1 wherein said retractor is a non-locking retractor allowing said safety belt means to be freely wound and unwound from said retractor under all conditions, said belt clamp apparatus responsive to an unwinding force on said belt means in said first direction above a first predetermined amount resulting from a pull on said belt means as a result of an emergency condition.

4. The safety restraint system according to claim 1 wherein said retractor comprises vehicle sensitive means for sensing acceleration, deceleration or change in orientation of said vehicle.

5. The safety restraint system according to claim 1 wherein said belt clamp apparatus comprises controlled slippage means for allowing movement of said belt means through said belt clamp apparatus in said first direction out of said retractor in response to an unwinding force on said belt means above a second predetermined amount, said second predetermined amount being greater than said first predetermined amount.

6. The safety restraint system according to claim 5 wherein said retractor comprises belt sensitive means responsive to an unwinding acceleration on said belt means above a third predetermined amount and locking means for preventing further unwinding of said belt means from said retractor when said unwinding force is above said third predetermined amount, said third predetermined amount being greater than said first predetermined amount and being greater than said second predetermined amount.

7. The safety restraint system according to claim 6 wherein said retractor further comprises vehicle sensitive means responsive to acceleration, deceleration or change in orientation of said vehicle and locking means for preventing further unwinding of said belt means from said retractor when said acceleration, deceleration or change in orientation is above a predetermined amount.

8. A force limiting safety restraint system for a seated occupant in a vehicle, said system having a safety belt passing over a shoulder of said occupant, said system comprising:

a belt clamp apparatus wherein said safety belt is movable through said clamp apparatus in a first direction and in an opposite second direction, said clamp apparatus resisting movement of said belt in said first direction when a force above a first predetermined amount is applied to said belt in said first direction, said clamp apparatus including a lever pivotable on a first shaft, said lever having a clamping position and a non-clamping position, and a first biasing means biasing said lever to its non-clamping position, a clamp bar having a first surface for contacting a portion of said belt, a mounting means on said lever for movably mounting said bar on said lever, said mounting means comprising a channel in said lever, means for retaining said bar in said mounting means of said lever, said retaining means comprising lip means associated with said channel, said clamp bar being freely movable within said channel, and pivot means on a second surface of said clamp bar opposite from said first surface, said clamp bar being movable on said pivot means with respect to said lever for applying a substantially uniform force over an area of contact of said belt; and

said belt clamp apparatus having controlled slippage means responsive to an unwinding force on said belt above a second predetermined amount resulting from a pull on said belt, said second predetermined amount being greater than said first predetermined amount, said controlled slippage means in response to said second predetermined amount of force allowing controlled slippage of said belt through said belt clamp apparatus; and

a retractor mounted in said vehicle below said belt clamp apparatus, said retractor having belt-sensitive means responsive to movement of said belt in an unwinding direction above a third predetermined value resulting from a pull on said belt and preventing further unwinding of said belt means from said retractor, said third predetermined value being greater than said second predetermined value.

9. The apparatus according to claim 8 wherein said controlled slippage means comprises a ratio of a first distance to a second distance, said first distance being from said first shaft to a top of said lever, said second distance being from the first shaft to said pivoting means of said bar.

10. The apparatus according to claim 8 wherein said controlled slippage means comprises the strength characteristics of said first biasing means.

11. The apparatus according to claim 8 wherein said controlled slippage means comprises the surface characteristics of the belt.

12. The apparatus according to claim 8 wherein said controlled slippage means comprises an included angle between the belt at the top of said lever and the belt at the bottom of said lever.

17. The apparatus according to claim 11 and further comprising a second surface on said first bracket, said second surface opposite from said first surface on said bar, said belt passing between said first surface and said second surface, said second surface having a frictional means.

18. The apparatus according to claim 17 wherein said frictional means on said second surface are knurls.

13. In a belt clamp apparatus wherein a safety belt is movable through said clamp apparatus in a first direction and in an opposite second direction, said clamp apparatus resisting movement of said belt in said first direction when a force above a first predetermined amount is applied to said belt in said first direction, said clamp apparatus including a lever pivotable on a first shaft, said lever having a clamping position and a non-clamping position, and a first biasing means biasing said lever to its non-clamping position, the improvement comprising:

a clamp bar having a first surface for contacting a portion of said belt;

a mounting means on said lever for movably mounting said bar on said lever, said mounting means comprising a channel in said lever;

means for retaining said bar in said mounting means of said lever, said retaining means comprising lip means associated with said channel, said clamp bar being freely movable within said channel; and

pivot means on a second surface of said clamp bar opposite from said first surface, said clamp bar being movable on said pivot means with respect to said lever for applying a substantially uniform force oveer an area of contact of said belt.

14. The apparatus according to claim 13 and further comprising means for mounting said apparatus to a vehicle, said mounting means comprising a pivot means for moving a portion of said apparatus in a substantially vertical plane, said pivot means including said first shaft.

15. The apparatus according to claim 14 wherein said pivot means comprises:

a first U-shaped bracket having a first side and a second side disposed parallel to one another in a substantially vertical plane, said lever disposed between said first and second sides, and said first shaft passing through said first and second sides and said lever.

16. The apparatus according to claim 15 wherein:

said first bracket further comprises a third side and a fourth side disposed parallel to one another in a substantially horizontal plane; and

said swivel means comprises;

a second U shaped bracket having a fifth side and a sixth side disposed parallel to one another in a substantially horizontal plane; and

a second shaft disposed in a substantially vertical plane and passing through said third and fourth sides of said first bracket and said fifth and sixth sides of said second bracket, whereby said first bracket swivels on said second shaft through a substantially horizontal plane with respect to said second bracket.

19. The apparatus according to claim 13 and further comprising a controlled slippage means responsive to force above a second predetermined amount greater than said first predetermined amount for allowing slippage of said belt in said first unwinding direction.

20. The apparatus according to claim 13 wherein said pivot means comprises a crest surface.

21. The apparatus according to claim 20 wherein said crest surface extends across the width of said bar.

22. The apparatus according to claim 21 wherein said lip means comprises a first lip on one side of said channel and a second lip on a second side of said channel.

23. The apparatus according to claim 22 and further comprising a second biasing means disposed in said channel and biasing said clamp bar away from said belt.

24. The apparatus according to claim 23 wherein said clamp bar is disposed adjacent to one end of said lever.

25. The apparatus according to claim 13 including means for even distributing said force laterally across the width of said belt.

26. The apparatus according to claim 25 wherein said means for distributing said force laterally across the width of said belt comprises resilient bushing means disposed around said first shaft.

27. In a belt clamp apparatus wherein a safety belt is movable through said clamp apparatus in a first direction and in an opposite second direction, said clamp apparatus resisting movement of said belt in said first direction when a force above a first predetermined amount is applied to said belt in said first direction, said clamp apparatus including a lever pivotable on a first shaft, said lever having a clamping position and a non-clamping position, and a first biasing means biasing said lever to its non-clamping position, the improvement comprising:

a clamp bar having a first surface for contacting a portion of said belt;

a mounting means on said lever for movably mounting said bar on said lever;

means for retaining said bar in said mounting means of said lever;

said mounting means comprising a channel in said lever and said means for retaining said bar in said mounting means comprising a first lip on a first side of said channel and a second lip on a second side of said channel; and

a crest on a second surface of said clamp bar opposite from said first surface, said clamp bar movable on said crest with respect to said lever for applying a substantially uniform force over an area of contact on said belt.

28. The apparatus according to claim 27 and further comprising a swivel means for moving a portion of said apparatus in a substantially horizontal plane.

29. The apparatus according to claim 27 wherein:

said biasing means is a spring, said spring having an elongated portion, two ends, and a hairpin turn at each end.

30. The apparatus according to claim 27 wherein said first surface has a frictional means for applying a braking force on a portion of said belt.

31. The apparatus according to claim 30 wherein said frictional means are knurls on said first surface.

32. The apparatus according to claim 27 and further comprising a recess in said bar adjacent to said first lip;

and a second biasing means disposed in said recess between said bar and said first lip of said lever.

33. In a belt clamp apparatus for a vehicle occupant restraint system wherein a safety belt is movable through said clamp apparatus in an unwinding direction and in an opposite winding direction, said clamp apparatus resisting movement of said belt in said unwinding direction when a force above a predetermined magnitude is applied to said safety belt in said unwinding direction, said clamp apparatus including a lever pivotable on a first shaft, said lever having a clamping position and non-clamping position, and a biasing means biasing said lever in its non-clamping position, the improvement comprising:

a resilient bushing means disposed around said first shaft;

a clamp bar having a first surface for contacting a portion of said belt;

a mounting means adjacent one end of said lever for movably mounting said bar on said lever, said mounting means comprising a channel in said lever, said bar disposed in said channel, a first lip on a first side of said channel and a second lip on a second side of said channel for retaining said bar is said channel;

a crest on a second surface of said bar opposite from said first surface, said bar movable on said crest in said channel for applying a substantially uniform force over an area of contact on said belt; and

a recess in said bar adjacent to said first lip; and

a spring disposed in said recess between said bar and said first lip of said lever.