Seat occupant restraint system for vehicle

• US 20010040065A1
• Filed: 04/12/2001
• Published: 11/15/2001
• Est. Priority Date: 05/15/2000
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Takagi, Hideo, Pal, Chinmoy
• Granted Patent: US 6,666,292 B2
• Time in Patent Office: Days
• US Class Current: 180/274
• CPC Class Codes: B60R 2021/0011 Rear collision or recoiling bounce after frontal collision
• CPC Class Codes: B60R 2021/01272 Belt tensioners
• CPC Class Codes: B60R 2022/4609 using a plurality of tensioners
• CPC Class Codes: B60R 21/0134 responsive to imminent contact with an obstacle , e.g. using radar systems
• CPC Class Codes: B60R 21/01516 using force or pressure sensing means
• CPC Class Codes: B60R 21/01554 Seat position sensors

Abstract

A rear end collision sensor is designed to detect the possibility of a rear end collision of a vehicle in advance. Upon detection, a controller drives a seat belt system to restrain the head of a seat occupant toward a headrest of the seat or to straighten the spine of the seat occupant to protect the neck against impending impact.

Claims

1. A vehicle comprising:

a seat comprising a seat cushion and a seat back;

a headrest mounted on an upper portion of the seat back;

a restrain system to secure a seat occupant on the seat so as to restrain the head of the seat occupant toward the headrest and straighten the spine of the seat occupant;

a rear end collision sensor to detect a possibility of a rear end collision of the vehicle in advance; and

a controller to drive the restrain system in response to detection of the possibility of a rear end collision.

2. The vehicle as claimed in

claim 1

, wherein the restrain system comprises an upper torso restraint designed to restrain movement of the chest and a shoulder of a seat occupant, and a first actuator connected with the upper torso restraint and arranged to produce a restraint force with the upper torso restraint in response to a first trigger signal produced by the controller to drive the restrain system.

3. The vehicle as claimed in

claim 2

, wherein the restrain system further comprises a pelvic restraint designed to restrain movement of the pelvis of a seat occupant, and a second actuator adapted to be connected with the pelvic restraint and arranged to produce a restraint force with the pelvic restraint in response to a second trigger signal produced by the controller.

4. The vehicle as claimed in

claim 3

, wherein the rear end collision sensor comprises a first section to sense a first condition to detect the possibility of a rear end collision of the vehicle and a second section to sense a second condition to detect the occurrence of a rear end collision of the vehicle;

and the controller is configured to produce a prediction signal when the possibility of a rear end collision is detected, and a collision signal when the occurrence of a rear end collision is detected, and further configured to produce the first trigger signal in response to the prediction signal to tighten the upper torso restraint before the occurrence of a rear end collision, and the second trigger signal in response to the collision signal to tighten the pelvic restraint upon the occurrence of a rear end collision.

5. The vehicle as claimed in

claim 4

, wherein the upper torso restraint comprises a shoulder belt designed to restrain a shoulder and the chest of a seat occupant;

the first actuator comprises a seat belt retractor to retract an upper portion of the shoulder belt; and

the controller drives the belt retractor to tighten the shoulder belt in response to the first trigger signal.

6. The vehicle as claimed in

claim 5

, wherein the pelvic restraint comprises a lap belt designed to extend from a first lateral side to a second lateral side across the lap of a seat occupant;

and the second actuator is designed to hold a lower portion of the shoulder belt and a first lateral side portion of the lap belt and to tighten the lap belt and the shoulder belt in response to the second trigger signal.

7. The vehicle as claimed in

claim 6

, wherein the lap belt and the shoulder belt are connected with each other, and the second actuator comprises a buckle actuator designed to increase belt tension of both the lap belt and the shoulder belt in response to the second trigger signal.

8. The vehicle as claimed in

claim 4

, wherein the first section of the rear end collision sensor comprises a distance sensor to sense a distance from the vehicle to a following vehicle behind;

and the controller is configured to calculate a first parameter representative of the possibility of a rear end collision in accordance with the distance, and to produce the prediction signal when the first parameter is equal to or greater than a threshold.

9. The vehicle as claimed in

claim 8

, wherein the first parameter representative of the possibility of a rear end collision is a quotient resulting from division by a divisor which increases linearly with increase in the distance, of a dividend proportional to the square of a relative speed of the following vehicle relative to the vehicle equipped with the rear end collision sensor, the relative speed being calculated from the distance.

10. The vehicle as claimed in

claim 8

, wherein the controller is configured to produce a first restore signal when the first parameter becomes smaller than the threshold, and the first actuator is arranged to slacken the upper torso restraint in response to the first restore signal.

11. The vehicle as claimed in

claim 8

, wherein the second section of the rear end collision sensor comprises a longitudinal acceleration sensor to sense a longitudinal acceleration of the vehicle equipped with the rear end collision sensor;

and the controller is configured to produce the collision signal when the longitudinal acceleration is greater than or equal to a threshold acceleration value.

12. The vehicle as claimed in

claim 4

, wherein the vehicle further comprises an occupant sensor to sense a seat condition to detect a nonstandard posture of a seat occupant;

and the controller is configured to respond to the prediction signal by controlling the first actuator and the second actuator in a first mode when the nonstandard posture is not detected, and in a second mode different from the first mode when the nonstandard posture is detected.

13. The vehicle as claimed in

claim 12

, wherein the controller is configured to produce only the first trigger signal in the first mode to increase the restraint force with only the first actuator before the occurrence of a rear end collision, and to produce both of the first trigger signal and the second trigger signal in the second mode to increase the restraint force with both the first actuator and the second actuator to correct the posture of a seat occupant before the occurrence of a rear end collision;

and wherein the occupant sensor comprises front and rear seat cushion load sensors and upper and lower seat back load sensors; and

the controller is configured to compare a cushion front load sensed by the front seat cushion load sensor and a cushion rear load sensed by the rear seat cushion load sensor with each other, further to compare a seat back upper load sensed by the upper seat back load sensor and a seat back lower load sensed by the lower seat back load sensor with each other, to produce a condition signal indicative of detection of a nonstandard posture when the cushion rear load is equal to or smaller than the cushion front load, and the seat back upper load is equal to or smaller than the seat back lower load, and to select the second mode when the condition signal indicative of detection of a nonstandard posture is present.

14. The vehicle as claimed in

claim 13

, wherein the controller is configured to produce a first restore signal and a second restore signal when the possibility of a rear end collision diminishes;

the first actuator is arranged to slacken the upper torso restraint to a limited extent in response to the first restore signal; and

the second actuator is arranged to slacken the pelvic restraint to a limited extent in response to the second restore signal.

15. The vehicle as claimed in

claim 12

, wherein the vehicle further comprises a seat cushion lifter, and the controller is configured to actuate the seat cushion lifter in the second mode so as to raise a front portion of the seat cushion and to lower a rear portion of the seat cushion.

16. The vehicle as claimed in

claim 4

, wherein the seat comprises a seat adjuster to correct the posture of a seat occupant by adjusting a condition of the seat in response to an adjuster actuation signal;

and the controller is configured to produce the adjuster actuation signal in response to the prediction signal before the occurrence of a rear end collision.

17. The vehicle as claimed in

claim 16

, wherein the seat adjuster comprises a seat back recliner;

the vehicle further comprises a seat back angle sensor to detect a reclined condition of the seat back; and

the controller is configured to produce the adjuster actuation signal to raise the seat back from the reclined condition when the reclined condition is detected.

18. The vehicle as claimed in

claim 4

, wherein the vehicle comprises a seat back recliner to rotate the seat back in a forward direction and in a rearward direction, and an occupant sensor to sense a weight of a seat occupant;

the rear collision sensor is configured to sense a relative speed of a following vehicle behind; and

the controller is configured to produce one of a rebound condition signal and an uplift condition signal in dependence on the weight and the relative speed just before a rear end collision, and to actuate the seat back recliner to rotate the seat back in the rearward direction in response to the rebound condition signal, and to rotate the seat back in the forward direction in response to the uplift condition signal.

19. The vehicle as claimed in

claim 2

, wherein the vehicle further comprises a lateral acceleration sensor for sensing a vehicle lateral acceleration, and an occupant sensor for sensing a posture of a seat occupant;

and the controller is configured to detect the possibility of sidewise deviation of the posture of the seat occupant, and to tighten the upper torso restraint when the possibility of sidewise deviation is detected.

20. The vehicle as claimed in

claim 1

, wherein the vehicle comprises a seat back recliner;

the rear end collision sensor comprises a longitudinal acceleration sensor for sensing a longitudinal acceleration of the vehicle; and

the controller is configured to detect the occurrence of a rear end collision by comparing the longitudinal acceleration with a reference acceleration value, further to detect the occurrence of a front end collision by comparing a longitudinal deceleration of the vehicle sensed by the longitudinal acceleration sensor with a reference deceleration value, and to rotate the seat back rearward with the seat back recliner when the occurrence of a front end collision is detected.

21. A seat occupant restraint apparatus comprising:

means for detecting a possibility of a rear end collision of a vehicle in advance; and

means for tightening a seat occupant restrain system to restrain the head of a seat occupant toward a headrest of a seat and to straighten the spine of the seat occupant when the possibility of a rear end collision is detected.

22. A seat occupant restraint control process comprising:

detecting a possibility of a rear end collision of a vehicle in advance; and

driving a seat occupant restrain system to restrain the head of a seat occupant toward a headrest of a seat and to straighten the spine of the seat occupant when the possibility of a rear end collision is detected.