System and Method for Moving a Headrest for Whiplash Prevention

• US 20080042477A1
• Filed: 10/26/2007
• Published: 02/21/2008
• Est. Priority Date: 12/17/1997
• Status: Active Grant

• Current Assignee: American Vehicular Sciences LLC (Acacia Research Corporation)
• Original Assignee: Automotive Technologies International Incorporated
• Inventors: Breed, David
• Granted Patent: US 7,588,115 B2
• Time in Patent Office: Days
• US Class Current: 297/216.12
• CPC Class Codes: B60N 2/02246 Electric motors therefor
• CPC Class Codes: B60N 2/4228 due to impact coming from the rear
• CPC Class Codes: B60N 2/4279 electric or electronic triggering
• CPC Class Codes: B60N 2/829 characterised by their adjusting mechanisms, e.g. electric motors
• CPC Class Codes: B60N 2/865 providing a fore-and-aft movement with respect to the occupant's head
• CPC Class Codes: B60N 2/888 with arrangements for protecting against abnormal g-forces, e.g. by displacement of the head-rest
• CPC Class Codes: B60R 2021/0011 Rear collision or recoiling bounce after frontal collision
• CPC Class Codes: B60R 2021/0048 Head
• CPC Class Codes: B60R 21/207 in vehicle seats

Abstract

System and method for preventing whiplash injuries to an occupant, in particular, during rear impacts, includes a movable headrest associated with the seat and a system for positioning the headrest adjacent a head of the occupant in an impact involving the vehicle. This latter system includes an anticipatory crash sensor system arranged to produce an output signal when an external object is approaching a rear of the vehicle at a velocity above a predetermined velocity, a headrest movement system arranged to move the headrest and a sensor system arranged to determine when the headrest contacts or is proximate the occupant'"'"'s head. Upon the determination of a pending rear impact between the object and the vehicle, the output signal is produced by the crash sensor system and the headrest is moved into a position in contact with or proximate the occupant'"'"'s head as determined by the sensor system.

Claims

1. A motor vehicle including a passenger compartment, comprising:

a seat on which an occupant sits;

a movable headrest associated with said seat; and

a system for positioning said headrest adjacent a head of the occupant in an impact involving the vehicle, said system comprising;

an anticipatory crash sensor system arranged to produce an output signal when an external object is approaching a rear of the vehicle at a velocity above a predetermined velocity;

a headrest movement system arranged to move said headrest; and

a sensor system arranged to determine when said headrest contacts or is proximate the occupant'"'"'s head;

whereby upon the determination of a pending rear impact between the external object and the vehicle, said output signal is produced by said crash sensor system and said headrest is then moved into a position in contact with or proximate the occupant'"'"'s head as determined by said sensor system prior to the impact of the occupant'"'"'s head with said headrest.

2. The vehicle of claim 1, wherein said headrest movement system is arranged to move said headrest from an initial position to a position proximate to the occupant'"'"'s head, and said sensor system is arranged to determine the location of the occupant'"'"'s head relative to said headrest, further comprising a processor arranged to determine the motion required of said headrest to place said headrest proximate the occupant'"'"'s head, said processor providing said motion determination to said headrest movement system upon receipt of the output signal from said crash sensor system, whereby upon the determination of a pending rear impact between the external object and the vehicle, said output signal is produced by said crash sensor system and said headrest is then moved into a position adjacent the occupant'"'"'s head prior to the impact of the occupant'"'"'s head with said headrest.

3. The vehicle of claim 2, wherein said sensor system comprises:

transmitter means attached to said headrest for transmitting radiation to illuminate different portions of the occupant'"'"'s head;

receiver means attached to said headrest for receiving a set of first signals representative of radiation reflected from said different portions of the occupant'"'"'s head, said receiver means providing a set of second signals representative of the distances from said headrest to the nearest illuminated portion of the occupant'"'"'s head; and

computational means for determining the headrest vertical location corresponding to the nearest part of the occupant'"'"'s head to said headrest from said set of second signals from said receiver means.

4. The vehicle of claim 2 wherein said sensor system is structured and arranged to be operable in the presence of objects which obscure the occupant'"'"'s head.

5. The vehicle of claim 4, wherein said sensor system comprise:

transmitter means for illuminating a selective portion of the occupant and the head-obscuring objects in the vicinity of the occupant'"'"'s head;

illumination sensor means for receiving illumination reflected from the occupant and the head-obscuring objects, said illumination sensor means providing a signal representative of the distance from said illumination sensor means to said illuminated portion of the occupant and the head-obscuring objects;

means for changing the selective portion of the occupant and the head-obscuring objects which is illuminated by the illumination, and

a processor comprising an algorithm for sequentially operating said selective portion changing means so as to illuminate different portions of the occupant and the head-obscuring objects to thereby obtain a plurality of distance measurements from said illumination sensor means to the different portions of the occupant and pattern recognition means for determining the location of the occupant'"'"'s head from the plurality of distance measurements from said illumination sensor means to the different portions of the occupant and the head-obscuring objects, wherein said processor, using said pattern recognition means, determines the location of the occupant'"'"'s head.

6. The vehicle of claim 5, wherein said pattern recognition means comprise a neural network.

7. The vehicle of claim 1, wherein said head location sensor means are structured and arranged to determine the location of the approximate longitudinal location of the head from said headrest.

8. The vehicle of claim 1, further comprising at least one airbag, said sensor system being structured and arranged to determine the location of the occupant'"'"'s head relative to said at least one airbag.

9. The vehicle of claim 1, wherein said crash sensor system comprises an ultrasonic transducer or an electromagnetic wave transducer.

10. The vehicle of claim 1, wherein said crash sensor system comprises means for measuring the distance from the vehicle to the object.

11. The vehicle of claim 1, wherein said crash sensor system comprises means for recognizing a pattern of the object to thereby identify the object.

12. The vehicle of claim 1, wherein said sensor system includes a switch which is contacted by the occupant'"'"'s head and then causes said headrest movement system to stop movement of said headrest.

13. The vehicle of claim 1, wherein said sensor system includes a proximity sensor which is arranged to detect when said headrest is proximate the occupant'"'"'s head and then cause said headrest movement system to stop movement of said headrest.

14. The vehicle of claim 1, wherein said sensor system comprises a contact sensor arranged in said headrest which is contacted by the occupant'"'"'s head and then causes said headrest movement system to stop movement of said headrest.

15. The vehicle of claim 1, wherein said headrest comprises a frame attached to said seat, an airbag containing air in a pre-inflated condition, means for maintaining said airbag in the pre-inflated condition prior to an impact of said headrest against the occupant'"'"'s head, supporting structure attached to said frame containing said pre-inflated airbag and having means for constraining the motion of said pre-inflated airbag to a substantially fore and aft direction, and a cover substantially surrounding said pre-inflated airbag, said cover elastically deformable in response to pressures from said pre-inflated airbag, wherein when the occupant'"'"'s head is impacted by said headrest, air within said pre-inflated airbag flows substantially within said airbag to change the shape of said airbag so as to approximately conform to the head and neck of the occupant.

16. The vehicle of claim 15, further comprising a flow restriction in said airbag to permit the controlled flow of air out of said airbag during the impact of said headrest against the occupant'"'"'s head to thereby dampen the impact of the occupant'"'"'s head onto said headrest.

17. A method for positioning a headrest of a seat in a vehicle in anticipation of a rear impact into the vehicle, comprising:

determining the location of the head relative to the headrest;

determining when an object external of the vehicle is approaching the rear of the vehicle at a velocity above a predetermined velocity which is indicative of a pending rear impact between the object and the vehicle; and

positioning the headrest adjacent a head of the occupant when a determination is made that the object is approaching at a velocity above the predetermined velocity and the determined location of the headrest is not adjacent the occupant'"'"'s head.

18. The method of claim 17, wherein the step of positioning the headrest comprises moving the headrest until the headrest contacts or is proximate the occupant'"'"'s head.

19. The method of claim 18, further comprising arranging a sensor in the headrest or seat to determine when the headrest contacts or is proximate the occupant'"'"'s head.

20. The method of claim 17, wherein the headrest is positioned adjacent the occupant'"'"'s head prior to the impact.