PLASTICALLY DEFORMABLE DAMPING MEMBER FOR MOTOR VEHICLE SAFETY BELTS

• US 3,561,690 A
• Filed: 12/13/1968
• Issued: 02/09/1971
• Est. Priority Date: 12/15/1967
• Status: Expired due to Term

• Current Assignee: Kurt Muskat
• Original Assignee: Kurt Muskat
• Inventors: MUSKAT KURT
• Application Number:
  US04/783,690
• Time in Patent Office: 788 Days
• US Class Current: 242/379.1
• CPC Class Codes: B60R 22/28 incorporating energy-absorbing devices belt anchors provided with energy-absorbing means for protecting the occupants in case of physical contact therewith B60R21/055; belt retractors comprising energy-absorbing means B60R22/341, B60R22/4676
• CPC Class Codes: F16F 7/123 Deformation involving a bending action, e.g. strap moving through multiple rollers, folding of members F16F7/125, F16F7/128 take precedence

Abstract

An energy absorbing device for motor vehicle safety belts comprises a plastically deformable damping member. The damping member is in the form of at least one coil of metal tape one end of which is secured to a rotatable shaft about which a length of belt is wound. The fixed reaction member is so located relative to the coil and shaft that the withdrawal of the length of belt from the shaft as the result of a collision causes the shaft to rotate and the fixed reaction member to deform the tape as it is drawn past the reaction member from the coil and is wound onto the rotatable shaft.

Claims

1. A damping device for a vehicle safety belt comprising:

a. an elongated plastically deformable nonelastic energy absorbing means, at least a part of which is in a coiled configuration constituting a storage coil;

b. rotatable means for securing one end of said energy absorbing means;

c. flexible means disposed at one end of the belt and secured to and coiled about said rotatable means; and

d. a fixed reaction member in contact with a part of said elongated energy absorbing means between said coil and said rotatable means and positioned such that when said elongated flexible means is uncoiled from said rotatable means as a result of a collision the momentum energy of a body retained by said belt is absorbed by a continuous change in the coiled configuration of the energy absorbing means as it is uncoiled, contacts said reaction member and is recoiled about said rotatable means without substantial alteration in the cross section of said energy absorbing means.

2. A damping device as claimed in claim 1 wherein said flexible means is coiled about said rotatable means in a direction opposite to the direction of the turns of said energy absorbing means in said storage coil whereby during a collision said energy absorbing means is coiled about said rotatable means in a direction opposite to the direction of the turns of the storage coil.

3. A damping device as claimed in claim 1 wherein the reaction member is offset on one side of the plane containing the axes of rotation of the storage coil and the rotatable means.

4. A damping device as claimed in claim 1 wherein said fixed reaction member is located at a predetermined distance from the axis of said rotatable means such that as the coil of the energy absorbing means builds up on the rotatable means the reaction member will eventually make contact with the exterior of said coil and act as a brake to reduce the rate of rotation and stop rotation of said rotatable means.

5. A damping device as claimed in claim 1 wherein said elongated energy absorbing means comprises a flat metal tape of varying width along its length.

6. A damping device as claimed in claim 5 wherein the width of said tape is diminished towards the end of the tape in said storage coil.

7. A damping device as claimed in claim 1 comprising two of said elongated plastically deformable nonelastic energy absorbing means.

8. A damping device as claimed in claim 1 further comprising a common chassis for mounting said reaction member and rotatable means and locating the storage coil.

9. A damping device as claimed in claim 7 further comprising a common chassis for mounting said reaction member and rotating means and locating the two storage coils, said flexible means being secured to and coiled about said rotatable means at a location between the locations at which the ends of said energy absorbing means are secured.

10. A damping device as claimed in claim 9 wherein said chassis comprises two pairs of parallel flanges, a storage coil being retained in alignment between each pair.

11. A damping device as claimed in claim 8 wherein said chassis contains an opening to receive said energy absorbing means as it is coiled about said rotatable means during a collision.

12. A damping device as claimed in claim 1 wherein said flexible means comprises one end portion of said belt.

13. A damping device as claimed in claim 1 wherein said flexible means comprises a steel rope.

14. A damping device as claimed in claim 1 wherein said flexible means comprises a steel wire.