Airbag development control apparatus

• US 7,509,196 B2
• Filed: 10/17/2005
• Issued: 03/24/2009
• Est. Priority Date: 11/02/2004
• Status: Expired due to Fees

• Current Assignee: Calsonic Kansei Corporation
• Original Assignee: Calsonic Kansei Corporation
• Inventors: Oishi, Mineyuki
• Primary Examiner(s): Black; Thomas G
• Assistant Examiner(s): LOUIE, WAE LENNY
• Application Number:
  US11/250,608
• Publication Number:
  US 20060095185A1
• Time in Patent Office: 1,254 Days
• Field of Search: 701/45, 701/46, 280/735, 280/736, 280/731, 280/741, 280/742, 180/282, 180/271
• US Class Current: 701/45
• CPC Class Codes: B60R 2021/01231 control of expansion timing or sequence
• CPC Class Codes: B60R 2021/01322 comprising variable thresholds, e.g. depending from other collision parameters
• 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 21/01332 by frequency or waveform analysis

Abstract

An anterior part of a vehicle is provided with a bumper armature as a structural member having high rigidity. A bumper is disposed front of the bumper armature, and a radiator and an engine are disposed behind the bumper armature. A collision determining device embedded with an acceleration sensor as an airbag development control apparatus is arranged in a position approximately in the center of a vehicle interior. A time period “t” during when a signal waveform curve outputted from the acceleration sensor reaches from a first threshold value to a second threshold value is measured to judge whether or not the time period “t” is equal to or less than a previously set time “s”. When t≦s satisfied, full development of an airbag in which both of inflators are activated is selected by determining that the collision is occurred under a high speed condition. When t>s is satisfied, depowered development of the airbag in which one of the inflators is activated is selected by determining that the collision is occurred under a non-high speed condition.

Claims

1. An airbag development control apparatus for a vehicle, comprising:

an acceleration sensor which generates an acceleration signal on collision of the vehicle;

a plurality of differing signal waveform curves outputted from the acceleration sensor for each differing collision mode;

a threshold value setter which sets a first threshold value and a second threshold value for the acceleration signal generated by the acceleration sensor, the second threshold value being larger than the first threshold value;

a time measurement circuit which measures a time period from a point of time in which the acceleration signal, generated at an initial stage of the collision by the acceleration sensor, has reached the first threshold value to a point of time in which the acceleration signal, having reached the first threshold value, reaches the second threshold value; and

a judgment circuit which compares preliminarily the time period measured by the time measurement circuit with a previously set time before the actual deployment of an airbag, capable of differentiating a degree of acceleration generated at the initial stage of collision to judge a difference of modes of collision, which activates a plurality of inflators to fully develop the airbag when the measured time period by the timer is equal to or less than the previously set time according to the comparison, and which activates one of the inflators to partially develop the airbag when the measured time period by the timer exceeds the previously set time according to the comparison; and

a structural member having high rigidity spread across the approximate whole width of the vehicle width capable of extinguishing the difference in collision area due to a difference in collision modes so that acceleration speed generated during collision to the structural member having high rigidity can be viewed as a difference in collision speed regardless of the state of collision.

2. The airbag development control apparatus according to claim 1, wherein, when the acceleration signal has exceeded the first threshold value and then once fell below the first threshold value without reaching the second threshold value, measurement is performed by setting an initial time period surpassing the first threshold value as standard, without setting a time period passing through the first threshold value during re-ascending as measurement standard.

3. A method for controlling development of an airbag of a vehicle, the method comprising:

generating an acceleration signal with an acceleration sensor on collision of the vehicle;

sampling a plurality of differing signal waveform curves outputted from the acceleration sensor for each differing collision mode;

setting a first threshold value and a second threshold value for the acceleration signal generated by the acceleration sensor, the second threshold value being larger than the first threshold value;

measuring a time period from a point of time in which the acceleration signal, generated at an initial stage of the collision has reached the first threshold value to a point of time in which the acceleration signal, having reached the first threshold value, reaches the second threshold value; and

comparing preliminarily the measured time period with a previously set time before the actual deployment of an airbag;

fully developing an airbag when the measured time period is equal to or less than the previously set time according to the comparison; and

partially developing the airbag when the measured time period exceeds the previously set time according to the comparison; and

setting a structural member having high rigidity spread across the approximate whole width of the vehicle width capable of extinguishing the difference in collision area due to a difference in collision modes so that acceleration speed generated during collision to the structural member having high rigidity can be reviewed as a difference in collision speed regardless of the state of collision.

4. The method for controlling the development of the airbag according to claim 3, the method further comprising:

when the acceleration signal has exceeded the first threshold value and then once fell below the first threshold value without reaching the second threshold value, measurement is performed by setting an initial time period surpassing the first threshold value as standard, without setting a time period passing through the first threshold value during re-ascending as measurement standard.

5. An airbag development control apparatus for a vehicle, comprising:

an acceleration sensor which generates an acceleration signal on collision of the vehicle;

a plurality of differing signal waveform curves outputted from the acceleration sensor for each differing collision mode;

a first threshold value transmission circuit which stores a first threshold value and which sends out the first threshold value;

a second threshold value transmission circuit which stores a second threshold value and which sends out the second threshold value;

a first threshold value comparison circuit which compares the acceleration signal outputted from the acceleration sensor with the first threshold value sent out from the first threshold value transmission circuit, and which outputs a first threshold value reaching signal when the acceleration signal has reached the first threshold value;

a second threshold value comparison circuit which compares the acceleration signal outputted from the acceleration sensor with the second threshold value sent out from the second threshold value transmission circuit, and which outputs a second threshold value reaching signal when the acceleration signal has reached the second threshold value;

a time measurement circuit which measures a time period from a point of time in which the acceleration signal, generated at an initial stage of the collision by the acceleration sensor has reached the first threshold value to a point of time in which the acceleration signal, having reached the first threshold value, reaches the second threshold value, according to the first threshold value reaching signal outputted from the first threshold value comparison circuit and the second threshold value reaching signal outputted from the second threshold value comparison circuit; and

a judgment circuit which compares preliminarily the time period measured by the time measurement circuit with a previously set time before the actual deployment of an airbag, capable of differentiating a degree of acceleration generated at the initial stage of collision to judge a difference of modes of collision, which activates a plurality of inflators to fully develop an airbag when the measured time period by the timer is equal to or less than the previously set time according to the comparison, and which activates one of the inflators to partially develop the airbag when the measured time period by the timer exceeds the previously set time according to the comparison; and

a structural member having high rigidity spread across the approximate whole width of the vehicle width capable of extinguishing the difference in collision area due to a difference in collision modes so that acceleration speed generated during collision to the structural member having high rigidity can be viewed as a difference in collision speed regardless of the state of collision.

6. The airbag development control apparatus according to claim 5, wherein, when the acceleration signal has exceeded the first threshold value and then once fell below the first threshold value without reaching the second threshold value, measurement is performed by setting an initial time period surpassing the first threshold value as standard, without setting a time period passing through the first threshold value during re-ascending as measurement standard.