Passenger protecting apparatus

• US 6,216,070 B1
• Filed: 09/28/1998
• Issued: 04/10/2001
• Est. Priority Date: 09/29/1997
• Status: Expired due to Fees

• Current Assignee: Calsonic Kansei Corporation
• Original Assignee: Calsonic Kansei Corporation
• Inventors: Saito, Yasuo, Kaneko, Kunihiro, Hayashi, Haruyoshi
• Primary Examiner(s): Zanelli, Michael J.
• Assistant Examiner(s): Gibson, Eric M.
• Application Number:
  US09/161,467
• Time in Patent Office: 925 Days
• Field of Search: 701/45, 280/728.1, 280/734, 280/735, 180/282
• US Class Current: 701/45
• CPC Class Codes: B60R 2021/0004 Frontal collision
• CPC Class Codes: B60R 2021/0006 Lateral collision
• CPC Class Codes: B60R 21/0132 responsive to vehicle motion parameters , e.g. to vehicle longitudinal or transversal deceleration or speed value
• CPC Class Codes: B60R 21/017 including arrangements for providing electric power to safety arrangements or their actuating means, e.g. to pyrotechnic fuses or electro-mechanic valves

Abstract

A passenger protecting apparatus for inflating an air bag or tightening a seat belt is provided that is smaller in size and more reliable than any previously known passenger protecting apparatus. The passenger protecting apparatus has two switches connected in series with a squib. The switches are controlled by a control unit using independent program routines in a redundant manner. The control unit combines front collision and side collision detection in one unit. The control unit controls the switches based on the outputs of several acceleration sensors, by comparing their respective outputs to threshold values.

Claims

1. A passenger protection apparatus comprising:

a first acceleration sensor;

a second acceleration sensor, the polarity of the output of the second acceleration sensor being opposite to that of the first acceleration sensor;

comparing means for comparing the output of the second acceleration sensor with a predetermined standard value, and generating a switch signal when the output exceeds the standard value;

collision judging means for estimating whether the collision is grave or not, on the basis of the output of the first acceleration sensor;

first AND gate means for receiving the output of the comparing means calculated for the first AND gate means, and the output of the collision judging means calculated for the first AND gate means;

second AND gate means for receiving, independently from the first AND gate means, the output of the comparing means calculated for the second AND gate means, and the output of the collision judging means calculated for the second AND gate means;

a squib; and

a first switching circuit, which is connected with the squib in series and is controlled so as to turn on, according to the outputs of the first AND gate means;

a second switching circuit, which is connected with the squib in series and is controlled so as to turn on, according to the outputs of the second AND gate means.

2. A passenger protection apparatus according to claim 1, further comprising:

a micro computer;

wherein said collision Judging means, said comparing means, and said first and second AND gate means are included in said microcomputer; and

the outputs of the collision judging means appear at different output ports of the micro computer.

3. A passenger protection apparatus according to claim 1, wherein the first and second acceleration sensors have the same characteristics.

4. A passenger protection apparatus according to claim 1, wherein the first acceleration sensor detects the acceleration in a higher range, and the second acceleration sensor detects the acceleration in a lower range.

5. A passenger protection apparatus according to claim 1, wherein:

the comparing means, the collision judging means, and the first and second AND gate means are realized as a software computer program routine.

6. A passenger protection apparatus comprising:

a squib for inflating an air bag or for tightening a seat belt;

a first acceleration sensor;

a second acceleration sensor;

the polarity of the output of the second acceleration sensor being opposite to that of the first acceleration sensor;

comparing means for comparing the output of the second acceleration sensor with a predetermined standard value, and generating a switch signal, when the output exceeds the standard value;

collision judging means for judging whether the collision is grave or not, on the basis of the output of the first acceleration sensor, and generating an ignition signal, according to the estimation;

means for controlling the squib, which generates a signal to inflate the air bag, on the basis of the ignition signal from the collision judging means and the switch signal from the comparing means;

wherein the collision judging means calculates the difference between the outputs of the first and second acceleration sensors, and estimates the severity of the collision, on the basis of the calculated difference.

7. A passenger protection apparatus according to claim 6, further comprising:

a third acceleration sensor;

a fourth acceleration sensor;

wherein the first acceleration sensor and the second acceleration sensor form a first set of acceleration sensors; and

the third acceleration sensor and the fourth acceleration sensor form a second set of acceleration sensors;

wherein the first set of acceleration sensors is orientated along the longitudinal direction of the vehicle; and

the second set of acceleration sensors is orientated along the transverse direction of the vehicle.

8. A passenger protection apparatus according to claim 7, wherein the first set of acceleration sensors and the second set of acceleration sensors have the same characteristics.

9. A passenger protection apparatus according to claim 8, wherein the collision judging means estimates whether the collision is a front collision or a side collision, on the basis of the polarities of the outputs of the first and second acceleration sensors.

10. A passenger protection apparatus according to claim 7, wherein the collision judging means estimates whether the collision is a front collision or a side collision, on the basis of the polarities of the outputs of the first and second sets of acceleration sensors.

11. A passenger protection apparatus according to claim 6, wherein the collision judging means estimates whether the collision is grave or not, on the basis of the outputs of the first and second acceleration sensors, and generates an ignition signal to actuate the squib, on the basis of the estimation.

12. A passenger protection apparatus according to claim 6, wherein the first acceleration sensor detects large accelerations and the second acceleration sensor detects small accelerations with higher sensitivity.

13. A passenger protection apparatus according to claim 12, wherein the first and second acceleration sensors detect longitudinal acceleration.

14. A passenger protecting apparatus for a passenger vehicle comprising:

an air bag or a seat belt;

a squib for inflating the air bag or for tightening the seat belt;

a capacitor for storing electric charge;

first and second switching circuits for the squib;

first and second acceleration sensors, which are arranged adjacent to each other with the polarities of their outputs being opposite to each other; and

a micro computer, which controls the first and second switching circuits, on the basis of the outputs of the first and second acceleration sensors;

wherein the micro computer comprises;

comparing means for comparing the output of the second acceleration sensor with a predetermined standard value, and generating a switch signal when the output exceeds the standard value;

collision judging means for comparing the output of the first acceleration sensor with another predetermined standard value for estimating the collision, when it receives the switch signal from the comparing means; and

wherein the micro computer generates an ignition signal to actuate the first and second switching circuits to actuate the squib, by providing the electric charge from the capacitor.

15. A passenger protection apparatus according to claim 14, wherein:

the switching circuit comprises a first switching circuit and a second switching circuit; and

the micro computer comprises;

a first output port;

a second output port;

first AND gate means for receiving the outputs of the collision judging means and the comparing means;

the first AND gate means providing its output to the first switching circuit via the first output port of the micro computer;

second AND gate means for receiving the outputs of the collision judging means and the comparing means;

wherein;

the outputs provided to the second AND gate means are calculated independently from the outputs provided to the first AND gate means; and

the second AND gate means providing its output to the second switching circuit via the second output port of the micro computer.

16. A passenger protection apparatus according to claim 15, wherein:

the first AND gate means is realized in the form of a software computer routine; and

the second AND gate means is realized in the form of a software computer routine.

17. A passenger protection apparatus according to claim 14, wherein the micro computer comprises:

acceleration level judging means for judging the level of acceleration, which receives the output of the first acceleration sensor, and provides a trigger signal to the collision judging means to start a collision estimating algorithm in the collision judging means, when the output of the first acceleration sensor exceeds a predetermined value.

18. A passenger protection apparatus according to claim 17, wherein:

the acceleration judging means is realized in the form of a software program routine.

19. A passenger protecting apparatus according to claim 14, wherein the apparatus comprises:

an air bag for front collisions;

an air bag for side collisions;

a front air bag squib for the front air bag;

a side air bag squib for the side air bag;

a front air bag capacitor for the front air bag squib;

a side air bag capacitor for the side air bag squib;

a front air bag switching circuit for the front air bag squib;

a side air bag switching circuit for the side air bag squib;

first and second transverse acceleration sensors, for detecting transverse acceleration;

a longitudinal acceleration sensor, for detecting longitudinal acceleration;

wherein the micro computer controls the switching circuits for each squib, on the basis of the outputs of the first and second transverse acceleration sensors and the longitudinal acceleration sensor.

20. A passenger protection apparatus according to claim 14, wherein:

the first and second acceleration sensors comprise first and second transverse acceleration sensors;

the first and second transverse acceleration sensors are arranged adjacently to each other in a back to back configuration;

the first and second transverse acceleration sensors output signals of opposite polarities;

the micro computer calculates the difference between the outputs of the first and second transverse acceleration sensors; and

the collision judging means estimates the severity of the collision on the basis of the difference.

21. A passenger protection apparatus according to claim 14, wherein:

the first and second acceleration sensors comprise first and second transverse acceleration sensors;

the micro computer calculates the difference of the outputs of the first and second transverse acceleration sensors; and

the collision judging means estimates the severity of the collision on the basis of the difference.

22. A passenger protection apparatus according to claim 21, wherein:

the micro computer estimates whether the collision is a collision from right side or from left side, on the basis of the polarities of the outputs of the first and second transverse acceleration sensors.

23. A passenger protection apparatus according to claim 14, wherein:

the first and second acceleration sensors are first and second longitudinal acceleration sensors; and

the micro computer calculates the difference between the outputs of the first and second longitudinal acceleration sensors; and

the collision judging means estimates the severity of the collision on the basis of the difference.

24. A passenger protection apparatus according to claim 14, wherein:

the comparing means is realized in the form of a software program routine; and

the collision judging means is realized in the form of a software program routine.